OpenFPGA/libs/EXTERNAL/tcl8.6.12/generic/tclIO.c

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/*
* tclIO.c --
*
* This file provides the generic portions (those that are the same on
* all platforms and for all channel types) of Tcl's IO facilities.
*
* Copyright (c) 1998-2000 Ajuba Solutions
* Copyright (c) 1995-1997 Sun Microsystems, Inc.
* Contributions from Don Porter, NIST, 2014. (not subject to US copyright)
*
* See the file "license.terms" for information on usage and redistribution of
* this file, and for a DISCLAIMER OF ALL WARRANTIES.
*/
#include "tclInt.h"
#include "tclIO.h"
#include <assert.h>
/*
* For each channel handler registered in a call to Tcl_CreateChannelHandler,
* there is one record of the following type. All of records for a specific
* channel are chained together in a singly linked list which is stored in
* the channel structure.
*/
typedef struct ChannelHandler {
Channel *chanPtr; /* The channel structure for this channel. */
int mask; /* Mask of desired events. */
Tcl_ChannelProc *proc; /* Procedure to call in the type of
* Tcl_CreateChannelHandler. */
ClientData clientData; /* Argument to pass to procedure. */
struct ChannelHandler *nextPtr;
/* Next one in list of registered handlers. */
} ChannelHandler;
/*
* This structure keeps track of the current ChannelHandler being invoked in
* the current invocation of Tcl_NotifyChannel. There is a potential
* problem if a ChannelHandler is deleted while it is the current one, since
* Tcl_NotifyChannel needs to look at the nextPtr field. To handle this
* problem, structures of the type below indicate the next handler to be
* processed for any (recursively nested) dispatches in progress. The
* nextHandlerPtr field is updated if the handler being pointed to is deleted.
* The nestedHandlerPtr field is used to chain together all recursive
* invocations, so that Tcl_DeleteChannelHandler can find all the recursively
* nested invocations of Tcl_NotifyChannel and compare the handler being
* deleted against the NEXT handler to be invoked in that invocation; when it
* finds such a situation, Tcl_DeleteChannelHandler updates the nextHandlerPtr
* field of the structure to the next handler.
*/
typedef struct NextChannelHandler {
ChannelHandler *nextHandlerPtr; /* The next handler to be invoked in
* this invocation. */
struct NextChannelHandler *nestedHandlerPtr;
/* Next nested invocation of
* Tcl_NotifyChannel. */
} NextChannelHandler;
/*
* The following structure is used by Tcl_GetsObj() to encapsulates the
* state for a "gets" operation.
*/
typedef struct GetsState {
Tcl_Obj *objPtr; /* The object to which UTF-8 characters
* will be appended. */
char **dstPtr; /* Pointer into objPtr's string rep where
* next character should be stored. */
Tcl_Encoding encoding; /* The encoding to use to convert raw bytes
* to UTF-8. */
ChannelBuffer *bufPtr; /* The current buffer of raw bytes being
* emptied. */
Tcl_EncodingState state; /* The encoding state just before the last
* external to UTF-8 conversion in
* FilterInputBytes(). */
int rawRead; /* The number of bytes removed from bufPtr
* in the last call to FilterInputBytes(). */
int bytesWrote; /* The number of bytes of UTF-8 data
* appended to objPtr during the last call to
* FilterInputBytes(). */
int charsWrote; /* The corresponding number of UTF-8
* characters appended to objPtr during the
* last call to FilterInputBytes(). */
int totalChars; /* The total number of UTF-8 characters
* appended to objPtr so far, just before the
* last call to FilterInputBytes(). */
} GetsState;
/*
* The following structure encapsulates the state for a background channel
* copy. Note that the data buffer for the copy will be appended to this
* structure.
*/
typedef struct CopyState {
struct Channel *readPtr; /* Pointer to input channel. */
struct Channel *writePtr; /* Pointer to output channel. */
int readFlags; /* Original read channel flags. */
int writeFlags; /* Original write channel flags. */
Tcl_WideInt toRead; /* Number of bytes to copy, or -1. */
Tcl_WideInt total; /* Total bytes transferred (written). */
Tcl_Interp *interp; /* Interp that started the copy. */
Tcl_Obj *cmdPtr; /* Command to be invoked at completion. */
int bufSize; /* Size of appended buffer. */
char buffer[1]; /* Copy buffer, this must be the last
* field. */
} CopyState;
/*
* All static variables used in this file are collected into a single instance
* of the following structure. For multi-threaded implementations, there is
* one instance of this structure for each thread.
*
* Notice that different structures with the same name appear in other files.
* The structure defined below is used in this file only.
*/
typedef struct ThreadSpecificData {
NextChannelHandler *nestedHandlerPtr;
/* This variable holds the list of nested
* Tcl_NotifyChannel invocations. */
ChannelState *firstCSPtr; /* List of all channels currently open,
* indexed by ChannelState, as only one
* ChannelState exists per set of stacked
* channels. */
Tcl_Channel stdinChannel; /* Static variable for the stdin channel. */
int stdinInitialized;
Tcl_Channel stdoutChannel; /* Static variable for the stdout channel. */
int stdoutInitialized;
Tcl_Channel stderrChannel; /* Static variable for the stderr channel. */
int stderrInitialized;
Tcl_Encoding binaryEncoding;
} ThreadSpecificData;
static Tcl_ThreadDataKey dataKey;
/*
* Structure to record a close callback. One such record exists for
* each close callback registered for a channel.
*/
typedef struct CloseCallback {
Tcl_CloseProc *proc; /* The procedure to call. */
ClientData clientData; /* Arbitrary one-word data to pass
* to the callback. */
struct CloseCallback *nextPtr; /* For chaining close callbacks. */
} CloseCallback;
/*
* Static functions in this file:
*/
static ChannelBuffer * AllocChannelBuffer(int length);
static void PreserveChannelBuffer(ChannelBuffer *bufPtr);
static void ReleaseChannelBuffer(ChannelBuffer *bufPtr);
static int IsShared(ChannelBuffer *bufPtr);
static void ChannelFree(Channel *chanPtr);
static void ChannelTimerProc(ClientData clientData);
static int ChanRead(Channel *chanPtr, char *dst, int dstSize);
static int CheckChannelErrors(ChannelState *statePtr,
int direction);
static int CheckForDeadChannel(Tcl_Interp *interp,
ChannelState *statePtr);
static void CheckForStdChannelsBeingClosed(Tcl_Channel chan);
static void CleanupChannelHandlers(Tcl_Interp *interp,
Channel *chanPtr);
static int CloseChannel(Tcl_Interp *interp, Channel *chanPtr,
int errorCode);
static int CloseChannelPart(Tcl_Interp *interp, Channel *chanPtr,
int errorCode, int flags);
static int CloseWrite(Tcl_Interp *interp, Channel *chanPtr);
static void CommonGetsCleanup(Channel *chanPtr);
static int CopyData(CopyState *csPtr, int mask);
static int MoveBytes(CopyState *csPtr);
static void MBCallback(CopyState *csPtr, Tcl_Obj *errObj);
static void MBError(CopyState *csPtr, int mask, int errorCode);
static int MBRead(CopyState *csPtr);
static int MBWrite(CopyState *csPtr);
static void MBEvent(ClientData clientData, int mask);
static void CopyEventProc(ClientData clientData, int mask);
static void CreateScriptRecord(Tcl_Interp *interp,
Channel *chanPtr, int mask, Tcl_Obj *scriptPtr);
static void DeleteChannelTable(ClientData clientData,
Tcl_Interp *interp);
static void DeleteScriptRecord(Tcl_Interp *interp,
Channel *chanPtr, int mask);
static int DetachChannel(Tcl_Interp *interp, Tcl_Channel chan);
static void DiscardInputQueued(ChannelState *statePtr,
int discardSavedBuffers);
static void DiscardOutputQueued(ChannelState *chanPtr);
static int DoRead(Channel *chanPtr, char *dst, int bytesToRead,
int allowShortReads);
static int DoReadChars(Channel *chan, Tcl_Obj *objPtr, int toRead,
int appendFlag);
static int FilterInputBytes(Channel *chanPtr,
GetsState *statePtr);
static int FlushChannel(Tcl_Interp *interp, Channel *chanPtr,
int calledFromAsyncFlush);
static int TclGetsObjBinary(Tcl_Channel chan, Tcl_Obj *objPtr);
static Tcl_Encoding GetBinaryEncoding(void);
static void FreeBinaryEncoding(ClientData clientData);
static Tcl_HashTable * GetChannelTable(Tcl_Interp *interp);
static int GetInput(Channel *chanPtr);
static void PeekAhead(Channel *chanPtr, char **dstEndPtr,
GetsState *gsPtr);
static int ReadBytes(ChannelState *statePtr, Tcl_Obj *objPtr,
int charsLeft);
static int ReadChars(ChannelState *statePtr, Tcl_Obj *objPtr,
int charsLeft, int *factorPtr);
static void RecycleBuffer(ChannelState *statePtr,
ChannelBuffer *bufPtr, int mustDiscard);
static int StackSetBlockMode(Channel *chanPtr, int mode);
static int SetBlockMode(Tcl_Interp *interp, Channel *chanPtr,
int mode);
static void StopCopy(CopyState *csPtr);
static void TranslateInputEOL(ChannelState *statePtr, char *dst,
const char *src, int *dstLenPtr, int *srcLenPtr);
static void UpdateInterest(Channel *chanPtr);
static int Write(Channel *chanPtr, const char *src,
int srcLen, Tcl_Encoding encoding);
static Tcl_Obj * FixLevelCode(Tcl_Obj *msg);
static void SpliceChannel(Tcl_Channel chan);
static void CutChannel(Tcl_Channel chan);
static int WillRead(Channel *chanPtr);
#define WriteChars(chanPtr, src, srcLen) \
Write(chanPtr, src, srcLen, chanPtr->state->encoding)
#define WriteBytes(chanPtr, src, srcLen) \
Write(chanPtr, src, srcLen, tclIdentityEncoding)
/*
* Simplifying helper macros. All may use their argument(s) multiple times.
* The ANSI C "prototypes" for the macros are listed below, together with a
* short description of what the macro does.
*
* --------------------------------------------------------------------------
* int BytesLeft(ChannelBuffer *bufPtr)
*
* Returns the number of bytes of data remaining in the buffer.
*
* int SpaceLeft(ChannelBuffer *bufPtr)
*
* Returns the number of bytes of space remaining at the end of the
* buffer.
*
* int IsBufferReady(ChannelBuffer *bufPtr)
*
* Returns whether a buffer has bytes available within it.
*
* int IsBufferEmpty(ChannelBuffer *bufPtr)
*
* Returns whether a buffer is entirely empty. Note that this is not the
* inverse of the above operation; trying to merge the two seems to lead
* to occasional crashes...
*
* int IsBufferFull(ChannelBuffer *bufPtr)
*
* Returns whether more data can be added to a buffer.
*
* int IsBufferOverflowing(ChannelBuffer *bufPtr)
*
* Returns whether a buffer has more data in it than it should.
*
* char *InsertPoint(ChannelBuffer *bufPtr)
*
* Returns a pointer to where characters should be added to the buffer.
*
* char *RemovePoint(ChannelBuffer *bufPtr)
*
* Returns a pointer to where characters should be removed from the
* buffer.
* --------------------------------------------------------------------------
*/
#define BytesLeft(bufPtr) ((bufPtr)->nextAdded - (bufPtr)->nextRemoved)
#define SpaceLeft(bufPtr) ((bufPtr)->bufLength - (bufPtr)->nextAdded)
#define IsBufferReady(bufPtr) ((bufPtr)->nextAdded > (bufPtr)->nextRemoved)
#define IsBufferEmpty(bufPtr) ((bufPtr)->nextAdded == (bufPtr)->nextRemoved)
#define IsBufferFull(bufPtr) ((bufPtr) && (bufPtr)->nextAdded >= (bufPtr)->bufLength)
#define IsBufferOverflowing(bufPtr) ((bufPtr)->nextAdded>(bufPtr)->bufLength)
#define InsertPoint(bufPtr) (&(bufPtr)->buf[(bufPtr)->nextAdded])
#define RemovePoint(bufPtr) (&(bufPtr)->buf[(bufPtr)->nextRemoved])
/*
* For working with channel state flag bits.
*/
#define SetFlag(statePtr, flag) ((statePtr)->flags |= (flag))
#define ResetFlag(statePtr, flag) ((statePtr)->flags &= ~(flag))
#define GotFlag(statePtr, flag) ((statePtr)->flags & (flag))
/*
* Macro for testing whether a string (in optionName, length len) matches a
* value (prefix matching rules). Arguments are the minimum length to match
* and the value to match against. (Can't use Tcl_GetIndexFromObj as this is
* used in a situation where no objects are available.)
*/
#define HaveOpt(minLength, nameString) \
((len > (minLength)) && (optionName[1] == (nameString)[1]) \
&& (strncmp(optionName, (nameString), len) == 0))
/*
* The ChannelObjType type. Used to store the result of looking up
* a channel name in the context of an interp. Saves the lookup
* result and values needed to check its continued validity.
*/
typedef struct ResolvedChanName {
ChannelState *statePtr; /* The saved lookup result */
Tcl_Interp *interp; /* The interp in which the lookup was done. */
int epoch; /* The epoch of the channel when the lookup
* was done. Use to verify validity. */
int refCount; /* Share this struct among many Tcl_Obj. */
} ResolvedChanName;
static void DupChannelInternalRep(Tcl_Obj *objPtr, Tcl_Obj *copyPtr);
static void FreeChannelInternalRep(Tcl_Obj *objPtr);
static const Tcl_ObjType chanObjType = {
"channel", /* name for this type */
FreeChannelInternalRep, /* freeIntRepProc */
DupChannelInternalRep, /* dupIntRepProc */
NULL, /* updateStringProc */
NULL /* setFromAnyProc */
};
#define BUSY_STATE(st, fl) \
((((st)->csPtrR) && ((fl) & TCL_READABLE)) || \
(((st)->csPtrW) && ((fl) & TCL_WRITABLE)))
#define MAX_CHANNEL_BUFFER_SIZE (1024*1024)
/*
*---------------------------------------------------------------------------
*
* ChanClose, ChanRead, ChanSeek, ChanThreadAction, ChanWatch, ChanWrite --
*
* Simplify the access to selected channel driver "methods" that are used
* in multiple places in a stereotypical fashion. These are just thin
* wrappers around the driver functions.
*
*---------------------------------------------------------------------------
*/
static inline int
ChanClose(
Channel *chanPtr,
Tcl_Interp *interp)
{
if (chanPtr->typePtr->closeProc != TCL_CLOSE2PROC) {
return chanPtr->typePtr->closeProc(chanPtr->instanceData, interp);
} else {
return chanPtr->typePtr->close2Proc(chanPtr->instanceData, interp, 0);
}
}
/*
*---------------------------------------------------------------------------
*
* ChanRead --
*
* Read up to dstSize bytes using the inputProc of chanPtr, store them at
* dst, and return the number of bytes stored.
*
* Results:
* The return value of the driver inputProc,
* - number of bytes stored at dst, ot
* - -1 on error, with a Posix error code available to the caller by
* calling Tcl_GetErrno().
*
* Side effects:
* The CHANNEL_BLOCKED and CHANNEL_EOF flags of the channel state are set
* as appropriate. On EOF, the inputEncodingFlags are set to perform
* ending operations on decoding.
*
* TODO - Is this really the right place for that?
*
*---------------------------------------------------------------------------
*/
static int
ChanRead(
Channel *chanPtr,
char *dst,
int dstSize)
{
int bytesRead, result;
/*
* If the caller asked for zero bytes, we'd force the inputProc to return
* zero bytes, and then misinterpret that as EOF.
*/
assert(dstSize > 0);
/*
* Each read op must set the blocked and eof states anew, not let
* the effect of prior reads leak through.
*/
if (GotFlag(chanPtr->state, CHANNEL_EOF)) {
chanPtr->state->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(chanPtr->state, CHANNEL_BLOCKED | CHANNEL_EOF);
chanPtr->state->inputEncodingFlags &= ~TCL_ENCODING_END;
if (WillRead(chanPtr) < 0) {
return -1;
}
bytesRead = chanPtr->typePtr->inputProc(chanPtr->instanceData,
dst, dstSize, &result);
/*
* Stop any flag leakage through stacked channel levels.
*/
if (GotFlag(chanPtr->state, CHANNEL_EOF)) {
chanPtr->state->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(chanPtr->state, CHANNEL_BLOCKED | CHANNEL_EOF);
chanPtr->state->inputEncodingFlags &= ~TCL_ENCODING_END;
if (bytesRead > 0) {
/*
* If we get a short read, signal up that we may be BLOCKED. We should
* avoid calling the driver because on some platforms we will block in
* the low level reading code even though the channel is set into
* nonblocking mode.
*/
if (bytesRead < dstSize) {
SetFlag(chanPtr->state, CHANNEL_BLOCKED);
}
} else if (bytesRead == 0) {
SetFlag(chanPtr->state, CHANNEL_EOF);
chanPtr->state->inputEncodingFlags |= TCL_ENCODING_END;
} else if (bytesRead < 0) {
if ((result == EWOULDBLOCK) || (result == EAGAIN)) {
SetFlag(chanPtr->state, CHANNEL_BLOCKED);
result = EAGAIN;
}
Tcl_SetErrno(result);
}
return bytesRead;
}
static inline Tcl_WideInt
ChanSeek(
Channel *chanPtr,
Tcl_WideInt offset,
int mode,
int *errnoPtr)
{
/*
* Note that we prefer the wideSeekProc if that field is available in the
* type and non-NULL.
*/
if (Tcl_ChannelWideSeekProc(chanPtr->typePtr) != NULL) {
return Tcl_ChannelWideSeekProc(chanPtr->typePtr)(chanPtr->instanceData,
offset, mode, errnoPtr);
}
if (offset<Tcl_LongAsWide(LONG_MIN) || offset>Tcl_LongAsWide(LONG_MAX)) {
*errnoPtr = EOVERFLOW;
return Tcl_LongAsWide(-1);
}
return Tcl_LongAsWide(Tcl_ChannelSeekProc(chanPtr->typePtr)(chanPtr->instanceData,
Tcl_WideAsLong(offset), mode, errnoPtr));
}
static inline void
ChanThreadAction(
Channel *chanPtr,
int action)
{
Tcl_DriverThreadActionProc *threadActionProc =
Tcl_ChannelThreadActionProc(chanPtr->typePtr);
if (threadActionProc != NULL) {
threadActionProc(chanPtr->instanceData, action);
}
}
static inline void
ChanWatch(
Channel *chanPtr,
int mask)
{
chanPtr->typePtr->watchProc(chanPtr->instanceData, mask);
}
static inline int
ChanWrite(
Channel *chanPtr,
const char *src,
int srcLen,
int *errnoPtr)
{
return chanPtr->typePtr->outputProc(chanPtr->instanceData, src, srcLen,
errnoPtr);
}
/*
*---------------------------------------------------------------------------
*
* TclInitIOSubsystem --
*
* Initialize all resources used by this subsystem on a per-process
* basis.
*
* Results:
* None.
*
* Side effects:
* Depends on the memory subsystems.
*
*---------------------------------------------------------------------------
*/
void
TclInitIOSubsystem(void)
{
/*
* By fetching thread local storage we take care of allocating it for each
* thread.
*/
(void) TCL_TSD_INIT(&dataKey);
}
/*
*-------------------------------------------------------------------------
*
* TclFinalizeIOSubsystem --
*
* Releases all resources used by this subsystem on a per-process basis.
* Closes all extant channels that have not already been closed because
* they were not owned by any interp.
*
* Results:
* None.
*
* Side effects:
* Depends on encoding and memory subsystems.
*
*-------------------------------------------------------------------------
*/
/* ARGSUSED */
void
TclFinalizeIOSubsystem(void)
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
Channel *chanPtr = NULL; /* Iterates over open channels. */
ChannelState *statePtr; /* State of channel stack */
int active = 1; /* Flag == 1 while there's still work to do */
int doflushnb;
/*
* Fetch the pre-TIP#398 compatibility flag.
*/
{
const char *s;
Tcl_DString ds;
s = TclGetEnv("TCL_FLUSH_NONBLOCKING_ON_EXIT", &ds);
doflushnb = ((s != NULL) && strcmp(s, "0"));
if (s != NULL) {
Tcl_DStringFree(&ds);
}
}
/*
* Walk all channel state structures known to this thread and close
* corresponding channels.
*/
while (active) {
/*
* Iterate through the open channel list, and find the first channel
* that isn't dead. We start from the head of the list each time,
* because the close action on one channel can close others.
*/
active = 0;
for (statePtr = tsdPtr->firstCSPtr;
statePtr != NULL;
statePtr = statePtr->nextCSPtr) {
chanPtr = statePtr->topChanPtr;
if (GotFlag(statePtr, CHANNEL_DEAD)) {
continue;
}
if (!GotFlag(statePtr, CHANNEL_INCLOSE | CHANNEL_CLOSED )
|| GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
ResetFlag(statePtr, BG_FLUSH_SCHEDULED);
active = 1;
break;
}
}
/*
* We've found a live (or bg-closing) channel. Close it.
*/
if (active) {
TclChannelPreserve((Tcl_Channel)chanPtr);
/*
* TIP #398: by default, we no longer set the channel back into
* blocking mode. To restore the old blocking behavior, the
* environment variable TCL_FLUSH_NONBLOCKING_ON_EXIT must be set
* and not be "0".
*/
if (doflushnb) {
/*
* Set the channel back into blocking mode to ensure that we
* wait for all data to flush out.
*/
(void) Tcl_SetChannelOption(NULL, (Tcl_Channel) chanPtr,
"-blocking", "on");
}
if ((chanPtr == (Channel *) tsdPtr->stdinChannel) ||
(chanPtr == (Channel *) tsdPtr->stdoutChannel) ||
(chanPtr == (Channel *) tsdPtr->stderrChannel)) {
/*
* Decrement the refcount which was earlier artificially
* bumped up to keep the channel from being closed.
*/
statePtr->refCount--;
}
if (statePtr->refCount <= 0) {
/*
* Close it only if the refcount indicates that the channel is
* not referenced from any interpreter. If it is, that
* interpreter will close the channel when it gets destroyed.
*/
(void) Tcl_Close(NULL, (Tcl_Channel) chanPtr);
} else {
/*
* The refcount is greater than zero, so flush the channel.
*/
Tcl_Flush((Tcl_Channel) chanPtr);
/*
* Call the device driver to actually close the underlying
* device for this channel.
*/
(void) ChanClose(chanPtr, NULL);
/*
* Finally, we clean up the fields in the channel data
* structure since all of them have been deleted already. We
* mark the channel with CHANNEL_DEAD to prevent any further
* IO operations on it.
*/
chanPtr->instanceData = NULL;
SetFlag(statePtr, CHANNEL_DEAD);
}
TclChannelRelease((Tcl_Channel)chanPtr);
}
}
TclpFinalizeSockets();
TclpFinalizePipes();
}
/*
*----------------------------------------------------------------------
*
* Tcl_SetStdChannel --
*
* This function is used to change the channels that are used for
* stdin/stdout/stderr in new interpreters.
*
* Results:
* None
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
void
Tcl_SetStdChannel(
Tcl_Channel channel,
int type) /* One of TCL_STDIN, TCL_STDOUT, TCL_STDERR. */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
int init = channel ? 1 : -1;
switch (type) {
case TCL_STDIN:
tsdPtr->stdinInitialized = init;
tsdPtr->stdinChannel = channel;
break;
case TCL_STDOUT:
tsdPtr->stdoutInitialized = init;
tsdPtr->stdoutChannel = channel;
break;
case TCL_STDERR:
tsdPtr->stderrInitialized = init;
tsdPtr->stderrChannel = channel;
break;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetStdChannel --
*
* Returns the specified standard channel.
*
* Results:
* Returns the specified standard channel, or NULL.
*
* Side effects:
* May cause the creation of a standard channel and the underlying file.
*
*----------------------------------------------------------------------
*/
Tcl_Channel
Tcl_GetStdChannel(
int type) /* One of TCL_STDIN, TCL_STDOUT, TCL_STDERR. */
{
Tcl_Channel channel = NULL;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
/*
* If the channels were not created yet, create them now and store them in
* the static variables.
*/
switch (type) {
case TCL_STDIN:
if (!tsdPtr->stdinInitialized) {
tsdPtr->stdinInitialized = -1;
tsdPtr->stdinChannel = TclpGetDefaultStdChannel(TCL_STDIN);
/*
* Artificially bump the refcount to ensure that the channel is
* only closed on exit.
*
* NOTE: Must only do this if stdinChannel is not NULL. It can be
* NULL in situations where Tcl is unable to connect to the
* standard input.
*/
if (tsdPtr->stdinChannel != NULL) {
tsdPtr->stdinInitialized = 1;
Tcl_RegisterChannel(NULL, tsdPtr->stdinChannel);
}
}
channel = tsdPtr->stdinChannel;
break;
case TCL_STDOUT:
if (!tsdPtr->stdoutInitialized) {
tsdPtr->stdoutInitialized = -1;
tsdPtr->stdoutChannel = TclpGetDefaultStdChannel(TCL_STDOUT);
if (tsdPtr->stdoutChannel != NULL) {
tsdPtr->stdoutInitialized = 1;
Tcl_RegisterChannel(NULL, tsdPtr->stdoutChannel);
}
}
channel = tsdPtr->stdoutChannel;
break;
case TCL_STDERR:
if (!tsdPtr->stderrInitialized) {
tsdPtr->stderrInitialized = -1;
tsdPtr->stderrChannel = TclpGetDefaultStdChannel(TCL_STDERR);
if (tsdPtr->stderrChannel != NULL) {
tsdPtr->stderrInitialized = 1;
Tcl_RegisterChannel(NULL, tsdPtr->stderrChannel);
}
}
channel = tsdPtr->stderrChannel;
break;
}
return channel;
}
/*
*----------------------------------------------------------------------
*
* Tcl_CreateCloseHandler
*
* Creates a close callback which will be called when the channel is
* closed.
*
* Results:
* None.
*
* Side effects:
* Causes the callback to be called in the future when the channel will
* be closed.
*
*----------------------------------------------------------------------
*/
void
Tcl_CreateCloseHandler(
Tcl_Channel chan, /* The channel for which to create the close
* callback. */
Tcl_CloseProc *proc, /* The callback routine to call when the
* channel will be closed. */
ClientData clientData) /* Arbitrary data to pass to the close
* callback. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
CloseCallback *cbPtr;
cbPtr = (CloseCallback *)ckalloc(sizeof(CloseCallback));
cbPtr->proc = proc;
cbPtr->clientData = clientData;
cbPtr->nextPtr = statePtr->closeCbPtr;
statePtr->closeCbPtr = cbPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_DeleteCloseHandler --
*
* Removes a callback that would have been called on closing the channel.
* If there is no matching callback then this function has no effect.
*
* Results:
* None.
*
* Side effects:
* The callback will not be called in the future when the channel is
* eventually closed.
*
*----------------------------------------------------------------------
*/
void
Tcl_DeleteCloseHandler(
Tcl_Channel chan, /* The channel for which to cancel the close
* callback. */
Tcl_CloseProc *proc, /* The procedure for the callback to
* remove. */
ClientData clientData) /* The callback data for the callback to
* remove. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
CloseCallback *cbPtr, *cbPrevPtr;
for (cbPtr = statePtr->closeCbPtr, cbPrevPtr = NULL;
cbPtr != NULL; cbPtr = cbPtr->nextPtr) {
if ((cbPtr->proc == proc) && (cbPtr->clientData == clientData)) {
if (cbPrevPtr == NULL) {
statePtr->closeCbPtr = cbPtr->nextPtr;
} else {
cbPrevPtr->nextPtr = cbPtr->nextPtr;
}
ckfree(cbPtr);
break;
}
cbPrevPtr = cbPtr;
}
}
/*
*----------------------------------------------------------------------
*
* GetChannelTable --
*
* Gets and potentially initializes the channel table for an interpreter.
* If it is initializing the table it also inserts channels for stdin,
* stdout and stderr if the interpreter is trusted.
*
* Results:
* A pointer to the hash table created, for use by the caller.
*
* Side effects:
* Initializes the channel table for an interpreter. May create channels
* for stdin, stdout and stderr.
*
*----------------------------------------------------------------------
*/
static Tcl_HashTable *
GetChannelTable(
Tcl_Interp *interp)
{
Tcl_HashTable *hTblPtr; /* Hash table of channels. */
Tcl_Channel stdinChan, stdoutChan, stderrChan;
hTblPtr = (Tcl_HashTable *)Tcl_GetAssocData(interp, "tclIO", NULL);
if (hTblPtr == NULL) {
hTblPtr = (Tcl_HashTable *)ckalloc(sizeof(Tcl_HashTable));
Tcl_InitHashTable(hTblPtr, TCL_STRING_KEYS);
Tcl_SetAssocData(interp, "tclIO",
(Tcl_InterpDeleteProc *) DeleteChannelTable, hTblPtr);
/*
* If the interpreter is trusted (not "safe"), insert channels for
* stdin, stdout and stderr (possibly creating them in the process).
*/
if (Tcl_IsSafe(interp) == 0) {
stdinChan = Tcl_GetStdChannel(TCL_STDIN);
if (stdinChan != NULL) {
Tcl_RegisterChannel(interp, stdinChan);
}
stdoutChan = Tcl_GetStdChannel(TCL_STDOUT);
if (stdoutChan != NULL) {
Tcl_RegisterChannel(interp, stdoutChan);
}
stderrChan = Tcl_GetStdChannel(TCL_STDERR);
if (stderrChan != NULL) {
Tcl_RegisterChannel(interp, stderrChan);
}
}
}
return hTblPtr;
}
/*
*----------------------------------------------------------------------
*
* DeleteChannelTable --
*
* Deletes the channel table for an interpreter, closing any open
* channels whose refcount reaches zero. This procedure is invoked when
* an interpreter is deleted, via the AssocData cleanup mechanism.
*
* Results:
* None.
*
* Side effects:
* Deletes the hash table of channels. May close channels. May flush
* output on closed channels. Removes any channeEvent handlers that were
* registered in this interpreter.
*
*----------------------------------------------------------------------
*/
static void
DeleteChannelTable(
ClientData clientData, /* The per-interpreter data structure. */
Tcl_Interp *interp) /* The interpreter being deleted. */
{
Tcl_HashTable *hTblPtr; /* The hash table. */
Tcl_HashSearch hSearch; /* Search variable. */
Tcl_HashEntry *hPtr; /* Search variable. */
Channel *chanPtr; /* Channel being deleted. */
ChannelState *statePtr; /* State of Channel being deleted. */
EventScriptRecord *sPtr, *prevPtr, *nextPtr;
/* Variables to loop over all channel events
* registered, to delete the ones that refer
* to the interpreter being deleted. */
/*
* Delete all the registered channels - this will close channels whose
* refcount reaches zero.
*/
hTblPtr = (Tcl_HashTable *)clientData;
for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); hPtr != NULL;
hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch)) {
chanPtr = (Channel *)Tcl_GetHashValue(hPtr);
statePtr = chanPtr->state;
/*
* Remove any fileevents registered in this interpreter.
*/
for (sPtr = statePtr->scriptRecordPtr, prevPtr = NULL;
sPtr != NULL; sPtr = nextPtr) {
nextPtr = sPtr->nextPtr;
if (sPtr->interp == interp) {
if (prevPtr == NULL) {
statePtr->scriptRecordPtr = nextPtr;
} else {
prevPtr->nextPtr = nextPtr;
}
Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr,
TclChannelEventScriptInvoker, sPtr);
TclDecrRefCount(sPtr->scriptPtr);
ckfree(sPtr);
} else {
prevPtr = sPtr;
}
}
/*
* Cannot call Tcl_UnregisterChannel because that procedure calls
* Tcl_GetAssocData to get the channel table, which might already be
* inaccessible from the interpreter structure. Instead, we emulate
* the behavior of Tcl_UnregisterChannel directly here.
*/
Tcl_DeleteHashEntry(hPtr);
statePtr->epoch++;
if (statePtr->refCount-- <= 1) {
if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
(void) Tcl_Close(interp, (Tcl_Channel) chanPtr);
}
}
}
Tcl_DeleteHashTable(hTblPtr);
ckfree(hTblPtr);
}
/*
*----------------------------------------------------------------------
*
* CheckForStdChannelsBeingClosed --
*
* Perform special handling for standard channels being closed. When
* given a standard channel, if the refcount is now 1, it means that the
* last reference to the standard channel is being explicitly closed. Now
* bump the refcount artificially down to 0, to ensure the normal
* handling of channels being closed will occur. Also reset the static
* pointer to the channel to NULL, to avoid dangling references.
*
* Results:
* None.
*
* Side effects:
* Manipulates the refcount on standard channels. May smash the global
* static pointer to a standard channel.
*
*----------------------------------------------------------------------
*/
static void
CheckForStdChannelsBeingClosed(
Tcl_Channel chan)
{
ChannelState *statePtr = ((Channel *) chan)->state;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (tsdPtr->stdinInitialized == 1
&& tsdPtr->stdinChannel != NULL
&& statePtr == ((Channel *)tsdPtr->stdinChannel)->state) {
if (statePtr->refCount < 2) {
statePtr->refCount = 0;
tsdPtr->stdinChannel = NULL;
return;
}
} else if (tsdPtr->stdoutInitialized == 1
&& tsdPtr->stdoutChannel != NULL
&& statePtr == ((Channel *)tsdPtr->stdoutChannel)->state) {
if (statePtr->refCount < 2) {
statePtr->refCount = 0;
tsdPtr->stdoutChannel = NULL;
return;
}
} else if (tsdPtr->stderrInitialized == 1
&& tsdPtr->stderrChannel != NULL
&& statePtr == ((Channel *)tsdPtr->stderrChannel)->state) {
if (statePtr->refCount < 2) {
statePtr->refCount = 0;
tsdPtr->stderrChannel = NULL;
return;
}
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_IsStandardChannel --
*
* Test if the given channel is a standard channel. No attempt is made to
* check if the channel or the standard channels are initialized or
* otherwise valid.
*
* Results:
* Returns 1 if true, 0 if false.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_IsStandardChannel(
Tcl_Channel chan) /* Channel to check. */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if ((chan == tsdPtr->stdinChannel)
|| (chan == tsdPtr->stdoutChannel)
|| (chan == tsdPtr->stderrChannel)) {
return 1;
} else {
return 0;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_RegisterChannel --
*
* Adds an already-open channel to the channel table of an interpreter.
* If the interpreter passed as argument is NULL, it only increments the
* channel refCount.
*
* Results:
* None.
*
* Side effects:
* May increment the reference count of a channel.
*
*----------------------------------------------------------------------
*/
void
Tcl_RegisterChannel(
Tcl_Interp *interp, /* Interpreter in which to add the channel. */
Tcl_Channel chan) /* The channel to add to this interpreter
* channel table. */
{
Tcl_HashTable *hTblPtr; /* Hash table of channels. */
Tcl_HashEntry *hPtr; /* Search variable. */
int isNew; /* Is the hash entry new or does it exist? */
Channel *chanPtr; /* The actual channel. */
ChannelState *statePtr; /* State of the actual channel. */
/*
* Always (un)register bottom-most channel in the stack. This makes
* management of the channel list easier because no manipulation is
* necessary during (un)stack operation.
*/
chanPtr = ((Channel *) chan)->state->bottomChanPtr;
statePtr = chanPtr->state;
if (statePtr->channelName == NULL) {
Tcl_Panic("Tcl_RegisterChannel: channel without name");
}
if (interp != NULL) {
hTblPtr = GetChannelTable(interp);
hPtr = Tcl_CreateHashEntry(hTblPtr, statePtr->channelName, &isNew);
if (!isNew) {
if (chan == Tcl_GetHashValue(hPtr)) {
return;
}
Tcl_Panic("Tcl_RegisterChannel: duplicate channel names");
}
Tcl_SetHashValue(hPtr, chanPtr);
}
statePtr->refCount++;
}
/*
*----------------------------------------------------------------------
*
* Tcl_UnregisterChannel --
*
* Deletes the hash entry for a channel associated with an interpreter.
* If the interpreter given as argument is NULL, it only decrements the
* reference count. (This all happens in the Tcl_DetachChannel helper
* function).
*
* Finally, if the reference count of the channel drops to zero, it is
* deleted.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* Calls Tcl_DetachChannel which deletes the hash entry for a channel
* associated with an interpreter.
*
* May delete the channel, which can have a variety of consequences,
* especially if we are forced to close the channel.
*
*----------------------------------------------------------------------
*/
int
Tcl_UnregisterChannel(
Tcl_Interp *interp, /* Interpreter in which channel is defined. */
Tcl_Channel chan) /* Channel to delete. */
{
ChannelState *statePtr; /* State of the real channel. */
statePtr = ((Channel *) chan)->state->bottomChanPtr->state;
if (GotFlag(statePtr, CHANNEL_INCLOSE)) {
if (interp != NULL) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"illegal recursive call to close through close-handler"
" of channel", -1));
}
return TCL_ERROR;
}
if (DetachChannel(interp, chan) != TCL_OK) {
return TCL_OK;
}
statePtr = ((Channel *) chan)->state->bottomChanPtr->state;
/*
* Perform special handling for standard channels being closed. If the
* refCount is now 1 it means that the last reference to the standard
* channel is being explicitly closed, so bump the refCount down
* artificially to 0. This will ensure that the channel is actually
* closed, below. Also set the static pointer to NULL for the channel.
*/
CheckForStdChannelsBeingClosed(chan);
/*
* If the refCount reached zero, close the actual channel.
*/
if (statePtr->refCount <= 0) {
Tcl_Preserve(statePtr);
if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
/*
* We don't want to re-enter Tcl_Close().
*/
if (!GotFlag(statePtr, CHANNEL_CLOSED)) {
if (Tcl_Close(interp, chan) != TCL_OK) {
SetFlag(statePtr, CHANNEL_CLOSED);
Tcl_Release(statePtr);
return TCL_ERROR;
}
}
}
SetFlag(statePtr, CHANNEL_CLOSED);
Tcl_Release(statePtr);
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_DetachChannel --
*
* Deletes the hash entry for a channel associated with an interpreter.
* If the interpreter given as argument is NULL, it only decrements the
* reference count. Even if the ref count drops to zero, the channel is
* NOT closed or cleaned up. This allows a channel to be detached from an
* interpreter and left in the same state it was in when it was
* originally returned by 'Tcl_OpenFileChannel', for example.
*
* This function cannot be used on the standard channels, and will return
* TCL_ERROR if that is attempted.
*
* This function should only be necessary for special purposes in which
* you need to generate a pristine channel from one that has already been
* used. All ordinary purposes will almost always want to use
* Tcl_UnregisterChannel instead.
*
* Provided the channel is not attached to any other interpreter, it can
* then be closed with Tcl_Close, rather than with Tcl_UnregisterChannel.
*
* Results:
* A standard Tcl result. If the channel is not currently registered with
* the given interpreter, TCL_ERROR is returned, otherwise TCL_OK.
* However no error messages are left in the interp's result.
*
* Side effects:
* Deletes the hash entry for a channel associated with an interpreter.
*
*----------------------------------------------------------------------
*/
int
Tcl_DetachChannel(
Tcl_Interp *interp, /* Interpreter in which channel is defined. */
Tcl_Channel chan) /* Channel to delete. */
{
if (Tcl_IsStandardChannel(chan)) {
return TCL_ERROR;
}
return DetachChannel(interp, chan);
}
/*
*----------------------------------------------------------------------
*
* DetachChannel --
*
* Deletes the hash entry for a channel associated with an interpreter.
* If the interpreter given as argument is NULL, it only decrements the
* reference count. Even if the ref count drops to zero, the channel is
* NOT closed or cleaned up. This allows a channel to be detached from an
* interpreter and left in the same state it was in when it was
* originally returned by 'Tcl_OpenFileChannel', for example.
*
* Results:
* A standard Tcl result. If the channel is not currently registered with
* the given interpreter, TCL_ERROR is returned, otherwise TCL_OK.
* However no error messages are left in the interp's result.
*
* Side effects:
* Deletes the hash entry for a channel associated with an interpreter.
*
*----------------------------------------------------------------------
*/
static int
DetachChannel(
Tcl_Interp *interp, /* Interpreter in which channel is defined. */
Tcl_Channel chan) /* Channel to delete. */
{
Tcl_HashTable *hTblPtr; /* Hash table of channels. */
Tcl_HashEntry *hPtr; /* Search variable. */
Channel *chanPtr; /* The real IO channel. */
ChannelState *statePtr; /* State of the real channel. */
/*
* Always (un)register bottom-most channel in the stack. This makes
* management of the channel list easier because no manipulation is
* necessary during (un)stack operation.
*/
chanPtr = ((Channel *) chan)->state->bottomChanPtr;
statePtr = chanPtr->state;
if (interp != NULL) {
hTblPtr = (Tcl_HashTable *)Tcl_GetAssocData(interp, "tclIO", NULL);
if (hTblPtr == NULL) {
return TCL_ERROR;
}
hPtr = Tcl_FindHashEntry(hTblPtr, statePtr->channelName);
if (hPtr == NULL) {
return TCL_ERROR;
}
if ((Channel *) Tcl_GetHashValue(hPtr) != chanPtr) {
return TCL_ERROR;
}
Tcl_DeleteHashEntry(hPtr);
statePtr->epoch++;
/*
* Remove channel handlers that refer to this interpreter, so that
* they will not be present if the actual close is delayed and more
* events happen on the channel. This may occur if the channel is
* shared between several interpreters, or if the channel has async
* flushing active.
*/
CleanupChannelHandlers(interp, chanPtr);
}
statePtr->refCount--;
return TCL_OK;
}
/*
*---------------------------------------------------------------------------
*
* Tcl_GetChannel --
*
* Finds an existing Tcl_Channel structure by name in a given
* interpreter. This function is public because it is used by
* channel-type-specific functions.
*
* Results:
* A Tcl_Channel or NULL on failure. If failed, interp's result object
* contains an error message. *modePtr is filled with the modes in which
* the channel was opened.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------------
*/
Tcl_Channel
Tcl_GetChannel(
Tcl_Interp *interp, /* Interpreter in which to find or create the
* channel. */
const char *chanName, /* The name of the channel. */
int *modePtr) /* Where to store the mode in which the
* channel was opened? Will contain an ORed
* combination of TCL_READABLE and
* TCL_WRITABLE, if non-NULL. */
{
Channel *chanPtr; /* The actual channel. */
Tcl_HashTable *hTblPtr; /* Hash table of channels. */
Tcl_HashEntry *hPtr; /* Search variable. */
const char *name; /* Translated name. */
/*
* Substitute "stdin", etc. Note that even though we immediately find the
* channel using Tcl_GetStdChannel, we still need to look it up in the
* specified interpreter to ensure that it is present in the channel
* table. Otherwise, safe interpreters would always have access to the
* standard channels.
*/
name = chanName;
if ((chanName[0] == 's') && (chanName[1] == 't')) {
chanPtr = NULL;
if (strcmp(chanName, "stdin") == 0) {
chanPtr = (Channel *) Tcl_GetStdChannel(TCL_STDIN);
} else if (strcmp(chanName, "stdout") == 0) {
chanPtr = (Channel *) Tcl_GetStdChannel(TCL_STDOUT);
} else if (strcmp(chanName, "stderr") == 0) {
chanPtr = (Channel *) Tcl_GetStdChannel(TCL_STDERR);
}
if (chanPtr != NULL) {
name = chanPtr->state->channelName;
}
}
hTblPtr = GetChannelTable(interp);
hPtr = Tcl_FindHashEntry(hTblPtr, name);
if (hPtr == NULL) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"can not find channel named \"%s\"", chanName));
Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "CHANNEL", chanName, NULL);
return NULL;
}
/*
* Always return bottom-most channel in the stack. This one lives the
* longest - other channels may go away unnoticed. The other APIs
* compensate where necessary to retrieve the topmost channel again.
*/
chanPtr = (Channel *)Tcl_GetHashValue(hPtr);
chanPtr = chanPtr->state->bottomChanPtr;
if (modePtr != NULL) {
*modePtr = chanPtr->state->flags & (TCL_READABLE|TCL_WRITABLE);
}
return (Tcl_Channel) chanPtr;
}
/*
*---------------------------------------------------------------------------
*
* TclGetChannelFromObj --
*
* Finds an existing Tcl_Channel structure by name in a given
* interpreter. This function is public because it is used by
* channel-type-specific functions.
*
* Results:
* A Tcl_Channel or NULL on failure. If failed, interp's result object
* contains an error message. *modePtr is filled with the modes in which
* the channel was opened.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------------
*/
int
TclGetChannelFromObj(
Tcl_Interp *interp, /* Interpreter in which to find or create the
* channel. */
Tcl_Obj *objPtr,
Tcl_Channel *channelPtr,
int *modePtr, /* Where to store the mode in which the
* channel was opened? Will contain an ORed
* combination of TCL_READABLE and
* TCL_WRITABLE, if non-NULL. */
int flags)
{
ChannelState *statePtr;
ResolvedChanName *resPtr = NULL;
Tcl_Channel chan;
(void)flags;
if (interp == NULL) {
return TCL_ERROR;
}
if (objPtr->typePtr == &chanObjType) {
/*
* Confirm validity of saved lookup results.
*/
resPtr = (ResolvedChanName *) objPtr->internalRep.twoPtrValue.ptr1;
statePtr = resPtr->statePtr;
if ((resPtr->interp == interp) /* Same interp context */
/* No epoch change in channel since lookup */
&& (resPtr->epoch == statePtr->epoch)) {
/*
* Have a valid saved lookup. Jump to end to return it.
*/
goto valid;
}
}
chan = Tcl_GetChannel(interp, TclGetString(objPtr), NULL);
if (chan == NULL) {
if (resPtr) {
FreeChannelInternalRep(objPtr);
}
return TCL_ERROR;
}
if (resPtr && resPtr->refCount == 1) {
/* Re-use the ResolvedCmdName struct */
Tcl_Release((ClientData) resPtr->statePtr);
} else {
TclFreeIntRep(objPtr);
resPtr = (ResolvedChanName *) ckalloc(sizeof(ResolvedChanName));
resPtr->refCount = 1;
objPtr->internalRep.twoPtrValue.ptr1 = (ClientData) resPtr;
objPtr->typePtr = &chanObjType;
}
statePtr = ((Channel *)chan)->state;
resPtr->statePtr = statePtr;
Tcl_Preserve((ClientData) statePtr);
resPtr->interp = interp;
resPtr->epoch = statePtr->epoch;
valid:
*channelPtr = (Tcl_Channel) statePtr->bottomChanPtr;
if (modePtr != NULL) {
*modePtr = statePtr->flags & (TCL_READABLE|TCL_WRITABLE);
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_CreateChannel --
*
* Creates a new entry in the hash table for a Tcl_Channel record.
*
* Results:
* Returns the new Tcl_Channel.
*
* Side effects:
* Creates a new Tcl_Channel instance and inserts it into the hash table.
*
*----------------------------------------------------------------------
*/
Tcl_Channel
Tcl_CreateChannel(
const Tcl_ChannelType *typePtr, /* The channel type record. */
const char *chanName, /* Name of channel to record. */
ClientData instanceData, /* Instance specific data. */
int mask) /* TCL_READABLE & TCL_WRITABLE to indicate if
* the channel is readable, writable. */
{
Channel *chanPtr; /* The channel structure newly created. */
ChannelState *statePtr; /* The stack-level independent state info for
* the channel. */
const char *name;
char *tmp;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
/*
* With the change of the Tcl_ChannelType structure to use a version in
* 8.3.2+, we have to make sure that our assumption that the structure
* remains a binary compatible size is true.
*
* If this assertion fails on some system, then it can be removed only if
* the user recompiles code with older channel drivers in the new system
* as well.
*/
assert(sizeof(Tcl_ChannelTypeVersion) == sizeof(Tcl_DriverBlockModeProc *));
assert(typePtr->typeName != NULL);
if (NULL == typePtr->closeProc) {
Tcl_Panic("channel type %s must define closeProc", typePtr->typeName);
}
if ((TCL_READABLE & mask) && (NULL == typePtr->inputProc)) {
Tcl_Panic("channel type %s must define inputProc when used for reader channel", typePtr->typeName);
}
if ((TCL_WRITABLE & mask) && (NULL == typePtr->outputProc)) {
Tcl_Panic("channel type %s must define outputProc when used for writer channel", typePtr->typeName);
}
if (NULL == typePtr->watchProc) {
Tcl_Panic("channel type %s must define watchProc", typePtr->typeName);
}
if ((NULL!=typePtr->wideSeekProc) && (NULL == typePtr->seekProc)) {
Tcl_Panic("channel type %s must define seekProc if defining wideSeekProc", typePtr->typeName);
}
/*
* JH: We could subsequently memset these to 0 to avoid the numerous
* assignments to 0/NULL below.
*/
chanPtr = (Channel *)ckalloc(sizeof(Channel));
statePtr = (ChannelState *)ckalloc(sizeof(ChannelState));
chanPtr->state = statePtr;
chanPtr->instanceData = instanceData;
chanPtr->typePtr = typePtr;
/*
* Set all the bits that are part of the stack-independent state
* information for the channel.
*/
if (chanName != NULL) {
unsigned len = strlen(chanName) + 1;
/*
* Make sure we allocate at least 7 bytes, so it fits for "stdout"
* later.
*/
tmp = (char *)ckalloc((len < 7) ? 7 : len);
strcpy(tmp, chanName);
} else {
tmp = (char *)ckalloc(7);
tmp[0] = '\0';
}
statePtr->channelName = tmp;
statePtr->flags = mask;
/*
* Set the channel to system default encoding.
*
* Note the strange bit of protection taking place here. If the system
* encoding name is reported back as "binary", something weird is
* happening. Tcl provides no "binary" encoding, so someone else has
* provided one. We ignore it so as not to interfere with the "magic"
* interpretation that Tcl_Channels give to the "-encoding binary" option.
*/
statePtr->encoding = NULL;
name = Tcl_GetEncodingName(NULL);
if (strcmp(name, "binary") != 0) {
statePtr->encoding = Tcl_GetEncoding(NULL, name);
}
statePtr->inputEncodingState = NULL;
statePtr->inputEncodingFlags = TCL_ENCODING_START;
statePtr->outputEncodingState = NULL;
statePtr->outputEncodingFlags = TCL_ENCODING_START;
/*
* Set the channel up initially in AUTO input translation mode to accept
* "\n", "\r" and "\r\n". Output translation mode is set to a platform
* specific default value. The eofChar is set to 0 for both input and
* output, so that Tcl does not look for an in-file EOF indicator (e.g.,
* ^Z) and does not append an EOF indicator to files.
*/
statePtr->inputTranslation = TCL_TRANSLATE_AUTO;
statePtr->outputTranslation = TCL_PLATFORM_TRANSLATION;
statePtr->inEofChar = 0;
statePtr->outEofChar = 0;
statePtr->unreportedError = 0;
statePtr->refCount = 0;
statePtr->closeCbPtr = NULL;
statePtr->curOutPtr = NULL;
statePtr->outQueueHead = NULL;
statePtr->outQueueTail = NULL;
statePtr->saveInBufPtr = NULL;
statePtr->inQueueHead = NULL;
statePtr->inQueueTail = NULL;
statePtr->chPtr = NULL;
statePtr->interestMask = 0;
statePtr->scriptRecordPtr = NULL;
statePtr->bufSize = CHANNELBUFFER_DEFAULT_SIZE;
statePtr->timer = NULL;
statePtr->csPtrR = NULL;
statePtr->csPtrW = NULL;
statePtr->outputStage = NULL;
/*
* As we are creating the channel, it is obviously the top for now.
*/
statePtr->topChanPtr = chanPtr;
statePtr->bottomChanPtr = chanPtr;
chanPtr->downChanPtr = NULL;
chanPtr->upChanPtr = NULL;
chanPtr->inQueueHead = NULL;
chanPtr->inQueueTail = NULL;
chanPtr->refCount = 0;
/*
* TIP #219, Tcl Channel Reflection API
*/
statePtr->chanMsg = NULL;
statePtr->unreportedMsg = NULL;
statePtr->epoch = 0;
/*
* Link the channel into the list of all channels; create an on-exit
* handler if there is not one already, to close off all the channels in
* the list on exit.
*
* JH: Could call Tcl_SpliceChannel, but need to avoid NULL check.
*
* TIP #218.
* AK: Just initialize the field to NULL before invoking Tcl_SpliceChannel
* We need Tcl_SpliceChannel, for the threadAction calls. There is no
* real reason to duplicate all of this.
* NOTE: All drivers using thread actions now have to perform their TSD
* manipulation only in their thread action proc. Doing it when
* creating their instance structures will collide with the thread
* action activity and lead to damaged lists.
*/
statePtr->nextCSPtr = NULL;
SpliceChannel((Tcl_Channel) chanPtr);
/*
* Install this channel in the first empty standard channel slot, if the
* channel was previously closed explicitly.
*/
if ((tsdPtr->stdinChannel == NULL) && (tsdPtr->stdinInitialized == 1)) {
strcpy(tmp, "stdin");
Tcl_SetStdChannel((Tcl_Channel) chanPtr, TCL_STDIN);
Tcl_RegisterChannel(NULL, (Tcl_Channel) chanPtr);
} else if ((tsdPtr->stdoutChannel == NULL) &&
(tsdPtr->stdoutInitialized == 1)) {
strcpy(tmp, "stdout");
Tcl_SetStdChannel((Tcl_Channel) chanPtr, TCL_STDOUT);
Tcl_RegisterChannel(NULL, (Tcl_Channel) chanPtr);
} else if ((tsdPtr->stderrChannel == NULL) &&
(tsdPtr->stderrInitialized == 1)) {
strcpy(tmp, "stderr");
Tcl_SetStdChannel((Tcl_Channel) chanPtr, TCL_STDERR);
Tcl_RegisterChannel(NULL, (Tcl_Channel) chanPtr);
}
return (Tcl_Channel) chanPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_StackChannel --
*
* Replaces an entry in the hash table for a Tcl_Channel record. The
* replacement is a new channel with same name, it supercedes the
* replaced channel. Input and output of the superceded channel is now
* going through the newly created channel and allows the arbitrary
* filtering/manipulation of the dataflow.
*
* Andreas Kupries <a.kupries@westend.com>, 12/13/1998 "Trf-Patch for
* filtering channels"
*
* Results:
* Returns the new Tcl_Channel, which actually contains the saved
* information about prevChan.
*
* Side effects:
* A new channel structure is allocated and linked below the existing
* channel. The channel operations and client data of the existing
* channel are copied down to the newly created channel, and the current
* channel has its operations replaced by the new typePtr.
*
*----------------------------------------------------------------------
*/
Tcl_Channel
Tcl_StackChannel(
Tcl_Interp *interp, /* The interpreter we are working in */
const Tcl_ChannelType *typePtr,
/* The channel type record for the new
* channel. */
ClientData instanceData, /* Instance specific data for the new
* channel. */
int mask, /* TCL_READABLE & TCL_WRITABLE to indicate if
* the channel is readable, writable. */
Tcl_Channel prevChan) /* The channel structure to replace */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
Channel *chanPtr, *prevChanPtr;
ChannelState *statePtr;
/*
* Find the given channel (prevChan) in the list of all channels. If we do
* not find it, then it was never registered correctly.
*
* This operation should occur at the top of a channel stack.
*/
statePtr = (ChannelState *) tsdPtr->firstCSPtr;
prevChanPtr = ((Channel *) prevChan)->state->topChanPtr;
while ((statePtr != NULL) && (statePtr->topChanPtr != prevChanPtr)) {
statePtr = statePtr->nextCSPtr;
}
if (statePtr == NULL) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"couldn't find state for channel \"%s\"",
Tcl_GetChannelName(prevChan)));
}
return NULL;
}
/*
* Here we check if the given "mask" matches the "flags" of the already
* existing channel.
*
* | - | R | W | RW |
* --+---+---+---+----+ <=> 0 != (chan->mask & prevChan->mask)
* - | | | | |
* R | | + | | + | The superceding channel is allowed to restrict
* W | | | + | + | the capabilities of the superceded one!
* RW| | + | + | + |
* --+---+---+---+----+
*/
if ((mask & (statePtr->flags & (TCL_READABLE | TCL_WRITABLE))) == 0) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"reading and writing both disallowed for channel \"%s\"",
Tcl_GetChannelName(prevChan)));
}
return NULL;
}
/*
* Flush the buffers. This ensures that any data still in them at this
* time is not handled by the new transformation. Restrict this to
* writable channels. Take care to hide a possible bg-copy in progress
* from Tcl_Flush and the CheckForChannelErrors inside.
*/
if ((mask & TCL_WRITABLE) != 0) {
CopyState *csPtrR = statePtr->csPtrR;
CopyState *csPtrW = statePtr->csPtrW;
statePtr->csPtrR = NULL;
statePtr->csPtrW = NULL;
/*
* TODO: Examine what can go wrong if Tcl_Flush() call disturbs
* the stacking state of this channel during its operations.
*/
if (Tcl_Flush((Tcl_Channel) prevChanPtr) != TCL_OK) {
statePtr->csPtrR = csPtrR;
statePtr->csPtrW = csPtrW;
if (interp) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"could not flush channel \"%s\"",
Tcl_GetChannelName(prevChan)));
}
return NULL;
}
statePtr->csPtrR = csPtrR;
statePtr->csPtrW = csPtrW;
}
/*
* Discard any input in the buffers. They are not yet read by the user of
* the channel, so they have to go through the new transformation before
* reading. As the buffers contain the untransformed form their contents
* are not only useless but actually distorts our view of the system.
*
* To preserve the information without having to read them again and to
* avoid problems with the location in the channel (seeking might be
* impossible) we move the buffers from the common state structure into
* the channel itself. We use the buffers in the channel below the new
* transformation to hold the data. In the future this allows us to write
* transformations which pre-read data and push the unused part back when
* they are going away.
*/
if (((mask & TCL_READABLE) != 0) && (statePtr->inQueueHead != NULL)) {
/*
* When statePtr->inQueueHead is not NULL, we know
* prevChanPtr->inQueueHead must be NULL.
*/
assert(prevChanPtr->inQueueHead == NULL);
assert(prevChanPtr->inQueueTail == NULL);
prevChanPtr->inQueueHead = statePtr->inQueueHead;
prevChanPtr->inQueueTail = statePtr->inQueueTail;
statePtr->inQueueHead = NULL;
statePtr->inQueueTail = NULL;
}
chanPtr = (Channel *)ckalloc(sizeof(Channel));
/*
* Save some of the current state into the new structure, reinitialize the
* parts which will stay with the transformation.
*
* Remarks:
*/
chanPtr->state = statePtr;
chanPtr->instanceData = instanceData;
chanPtr->typePtr = typePtr;
chanPtr->downChanPtr = prevChanPtr;
chanPtr->upChanPtr = NULL;
chanPtr->inQueueHead = NULL;
chanPtr->inQueueTail = NULL;
chanPtr->refCount = 0;
/*
* Place new block at the head of a possibly existing list of previously
* stacked channels.
*/
prevChanPtr->upChanPtr = chanPtr;
statePtr->topChanPtr = chanPtr;
/*
* TIP #218, Channel Thread Actions.
*
* We call the thread actions for the new channel directly. We _cannot_
* use SpliceChannel, because the (thread-)global list of all channels
* always contains the _ChannelState_ for a stack of channels, not the
* individual channels. And SpliceChannel would not only call the thread
* actions, but also add the shared ChannelState to this list a second
* time, mangling it.
*/
ChanThreadAction(chanPtr, TCL_CHANNEL_THREAD_INSERT);
return (Tcl_Channel) chanPtr;
}
void
TclChannelPreserve(
Tcl_Channel chan)
{
((Channel *)chan)->refCount++;
}
void
TclChannelRelease(
Tcl_Channel chan)
{
Channel *chanPtr = (Channel *) chan;
if (chanPtr->refCount == 0) {
Tcl_Panic("Channel released more than preserved");
}
if (--chanPtr->refCount) {
return;
}
if (chanPtr->typePtr == NULL) {
ckfree(chanPtr);
}
}
static void
ChannelFree(
Channel *chanPtr)
{
if (chanPtr->refCount == 0) {
ckfree(chanPtr);
return;
}
chanPtr->typePtr = NULL;
}
/*
*----------------------------------------------------------------------
*
* Tcl_UnstackChannel --
*
* Unstacks an entry in the hash table for a Tcl_Channel record. This is
* the reverse to 'Tcl_StackChannel'.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* If TCL_ERROR is returned, the posix error code will be set with
* Tcl_SetErrno. May leave a message in interp result as well.
*
*----------------------------------------------------------------------
*/
int
Tcl_UnstackChannel(
Tcl_Interp *interp, /* The interpreter we are working in */
Tcl_Channel chan) /* The channel to unstack */
{
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
int result = 0;
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
if (chanPtr->downChanPtr != NULL) {
/*
* Instead of manipulating the per-thread / per-interp list/hashtable
* of registered channels we wind down the state of the
* transformation, and then restore the state of underlying channel
* into the old structure.
*
* TODO: Figure out how to handle the situation where the chan
* operations called below by this unstacking operation cause
* another unstacking recursively. In that case the downChanPtr
* value we're holding on to will not be the right thing.
*/
Channel *downChanPtr = chanPtr->downChanPtr;
/*
* Flush the buffers. This ensures that any data still in them at this
* time _is_ handled by the transformation we are unstacking right
* now. Restrict this to writable channels. Take care to hide a
* possible bg-copy in progress from Tcl_Flush and the
* CheckForChannelErrors inside.
*/
if (GotFlag(statePtr, TCL_WRITABLE)) {
CopyState *csPtrR = statePtr->csPtrR;
CopyState *csPtrW = statePtr->csPtrW;
statePtr->csPtrR = NULL;
statePtr->csPtrW = NULL;
if (Tcl_Flush((Tcl_Channel) chanPtr) != TCL_OK) {
statePtr->csPtrR = csPtrR;
statePtr->csPtrW = csPtrW;
/*
* TIP #219, Tcl Channel Reflection API.
* Move error messages put by the driver into the chan/ip
* bypass area into the regular interpreter result. Fall back
* to the regular message if nothing was found in the
* bypasses.
*/
if (!TclChanCaughtErrorBypass(interp, chan) && interp) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"could not flush channel \"%s\"",
Tcl_GetChannelName((Tcl_Channel) chanPtr)));
}
return TCL_ERROR;
}
statePtr->csPtrR = csPtrR;
statePtr->csPtrW = csPtrW;
}
/*
* Anything in the input queue and the push-back buffers of the
* transformation going away is transformed data, but not yet read. As
* unstacking means that the caller does not want to see transformed
* data any more we have to discard these bytes. To avoid writing an
* analogue to 'DiscardInputQueued' we move the information in the
* push back buffers to the input queue and then call
* 'DiscardInputQueued' on that.
*/
if (GotFlag(statePtr, TCL_READABLE) &&
((statePtr->inQueueHead != NULL) ||
(chanPtr->inQueueHead != NULL))) {
if ((statePtr->inQueueHead != NULL) &&
(chanPtr->inQueueHead != NULL)) {
statePtr->inQueueTail->nextPtr = chanPtr->inQueueHead;
statePtr->inQueueTail = chanPtr->inQueueTail;
statePtr->inQueueHead = statePtr->inQueueTail;
} else if (chanPtr->inQueueHead != NULL) {
statePtr->inQueueHead = chanPtr->inQueueHead;
statePtr->inQueueTail = chanPtr->inQueueTail;
}
chanPtr->inQueueHead = NULL;
chanPtr->inQueueTail = NULL;
DiscardInputQueued(statePtr, 0);
}
/*
* TIP #218, Channel Thread Actions.
*
* We call the thread actions for the new channel directly. We
* _cannot_ use CutChannel, because the (thread-)global list of all
* channels always contains the _ChannelState_ for a stack of
* channels, not the individual channels. And SpliceChannel would not
* only call the thread actions, but also remove the shared
* ChannelState from this list despite there being more channels for
* the state which are still active.
*/
ChanThreadAction(chanPtr, TCL_CHANNEL_THREAD_REMOVE);
statePtr->topChanPtr = downChanPtr;
downChanPtr->upChanPtr = NULL;
/*
* Leave this link intact for closeproc
* chanPtr->downChanPtr = NULL;
*/
/*
* Close and free the channel driver state.
*/
result = ChanClose(chanPtr, interp);
ChannelFree(chanPtr);
UpdateInterest(statePtr->topChanPtr);
if (result != 0) {
Tcl_SetErrno(result);
/*
* TIP #219, Tcl Channel Reflection API.
* Move error messages put by the driver into the chan/ip bypass
* area into the regular interpreter result.
*/
TclChanCaughtErrorBypass(interp, chan);
return TCL_ERROR;
}
} else {
/*
* This channel does not cover another one. Simply do a close, if
* necessary.
*/
if (statePtr->refCount <= 0) {
if (Tcl_Close(interp, chan) != TCL_OK) {
/*
* TIP #219, Tcl Channel Reflection API.
* "TclChanCaughtErrorBypass" is not required here, it was
* done already by "Tcl_Close".
*/
return TCL_ERROR;
}
}
/*
* TIP #218, Channel Thread Actions.
* Not required in this branch, this is done by Tcl_Close. If
* Tcl_Close is not called then the ChannelState is still active in
* the thread and no action has to be taken either.
*/
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetStackedChannel --
*
* Determines whether the specified channel is stacked upon another.
*
* Results:
* NULL if the channel is not stacked upon another one, or a reference to
* the channel it is stacked upon. This reference can be used in queries,
* but modification is not allowed.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_Channel
Tcl_GetStackedChannel(
Tcl_Channel chan)
{
Channel *chanPtr = (Channel *) chan;
/* The actual channel. */
return (Tcl_Channel) chanPtr->downChanPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetTopChannel --
*
* Returns the top channel of a channel stack.
*
* Results:
* NULL if the channel is not stacked upon another one, or a reference to
* the channel it is stacked upon. This reference can be used in queries,
* but modification is not allowed.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_Channel
Tcl_GetTopChannel(
Tcl_Channel chan)
{
Channel *chanPtr = (Channel *) chan;
/* The actual channel. */
return (Tcl_Channel) chanPtr->state->topChanPtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelInstanceData --
*
* Returns the client data associated with a channel.
*
* Results:
* The client data.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
ClientData
Tcl_GetChannelInstanceData(
Tcl_Channel chan) /* Channel for which to return client data. */
{
Channel *chanPtr = (Channel *) chan;
/* The actual channel. */
return chanPtr->instanceData;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelThread --
*
* Given a channel structure, returns the thread managing it. TIP #10
*
* Results:
* Returns the id of the thread managing the channel.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_ThreadId
Tcl_GetChannelThread(
Tcl_Channel chan) /* The channel to return the managing thread
* for. */
{
Channel *chanPtr = (Channel *) chan;
/* The actual channel. */
return chanPtr->state->managingThread;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelType --
*
* Given a channel structure, returns the channel type structure.
*
* Results:
* Returns a pointer to the channel type structure.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
const Tcl_ChannelType *
Tcl_GetChannelType(
Tcl_Channel chan) /* The channel to return type for. */
{
Channel *chanPtr = (Channel *) chan;
/* The actual channel. */
return chanPtr->typePtr;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelMode --
*
* Computes a mask indicating whether the channel is open for reading and
* writing.
*
* Results:
* An OR-ed combination of TCL_READABLE and TCL_WRITABLE.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_GetChannelMode(
Tcl_Channel chan) /* The channel for which the mode is being
* computed. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of actual channel. */
return (statePtr->flags & (TCL_READABLE | TCL_WRITABLE));
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelName --
*
* Returns the string identifying the channel name.
*
* Results:
* The string containing the channel name. This memory is owned by the
* generic layer and should not be modified by the caller.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
const char *
Tcl_GetChannelName(
Tcl_Channel chan) /* The channel for which to return the name. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of actual channel. */
return statePtr->channelName;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelHandle --
*
* Returns an OS handle associated with a channel.
*
* Results:
* Returns TCL_OK and places the handle in handlePtr, or returns
* TCL_ERROR on failure.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_GetChannelHandle(
Tcl_Channel chan, /* The channel to get file from. */
int direction, /* TCL_WRITABLE or TCL_READABLE. */
ClientData *handlePtr) /* Where to store handle */
{
Channel *chanPtr; /* The actual channel. */
ClientData handle;
int result;
chanPtr = ((Channel *) chan)->state->bottomChanPtr;
if (!chanPtr->typePtr->getHandleProc) {
Tcl_SetChannelError(chan, Tcl_ObjPrintf(
"channel \"%s\" does not support OS handles",
Tcl_GetChannelName(chan)));
return TCL_ERROR;
}
result = chanPtr->typePtr->getHandleProc(chanPtr->instanceData, direction,
&handle);
if (handlePtr) {
*handlePtr = handle;
}
return result;
}
/*
*---------------------------------------------------------------------------
*
* AllocChannelBuffer --
*
* A channel buffer has BUFFER_PADDING bytes extra at beginning to hold
* any bytes of a native-encoding character that got split by the end of
* the previous buffer and need to be moved to the beginning of the next
* buffer to make a contiguous string so it can be converted to UTF-8.
*
* A channel buffer has BUFFER_PADDING bytes extra at the end to hold any
* bytes of a native-encoding character (generated from a UTF-8
* character) that overflow past the end of the buffer and need to be
* moved to the next buffer.
*
* Results:
* A newly allocated channel buffer.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------------
*/
static ChannelBuffer *
AllocChannelBuffer(
int length) /* Desired length of channel buffer. */
{
ChannelBuffer *bufPtr;
int n;
n = length + CHANNELBUFFER_HEADER_SIZE + BUFFER_PADDING + BUFFER_PADDING;
bufPtr = (ChannelBuffer *)ckalloc(n);
bufPtr->nextAdded = BUFFER_PADDING;
bufPtr->nextRemoved = BUFFER_PADDING;
bufPtr->bufLength = length + BUFFER_PADDING;
bufPtr->nextPtr = NULL;
bufPtr->refCount = 1;
return bufPtr;
}
static void
PreserveChannelBuffer(
ChannelBuffer *bufPtr)
{
if (bufPtr->refCount == 0) {
Tcl_Panic("Reuse of ChannelBuffer! %p", bufPtr);
}
bufPtr->refCount++;
}
static void
ReleaseChannelBuffer(
ChannelBuffer *bufPtr)
{
if (--bufPtr->refCount) {
return;
}
ckfree(bufPtr);
}
static int
IsShared(
ChannelBuffer *bufPtr)
{
return bufPtr->refCount > 1;
}
/*
*----------------------------------------------------------------------
*
* RecycleBuffer --
*
* Helper function to recycle input and output buffers. Ensures that two
* input buffers are saved (one in the input queue and another in the
* saveInBufPtr field) and that curOutPtr is set to a buffer. Only if
* these conditions are met is the buffer freed to the OS.
*
* Results:
* None.
*
* Side effects:
* May free a buffer to the OS.
*
*----------------------------------------------------------------------
*/
static void
RecycleBuffer(
ChannelState *statePtr, /* ChannelState in which to recycle buffers. */
ChannelBuffer *bufPtr, /* The buffer to recycle. */
int mustDiscard) /* If nonzero, free the buffer to the OS,
* always. */
{
/*
* Do we have to free the buffer to the OS?
*/
if (IsShared(bufPtr)) {
mustDiscard = 1;
}
if (mustDiscard) {
ReleaseChannelBuffer(bufPtr);
return;
}
/*
* Only save buffers which have the requested buffersize for the channel.
* This is to honor dynamic changes of the buffersize made by the user.
*/
if ((bufPtr->bufLength - BUFFER_PADDING) != statePtr->bufSize) {
ReleaseChannelBuffer(bufPtr);
return;
}
/*
* Only save buffers for the input queue if the channel is readable.
*/
if (GotFlag(statePtr, TCL_READABLE)) {
if (statePtr->inQueueHead == NULL) {
statePtr->inQueueHead = bufPtr;
statePtr->inQueueTail = bufPtr;
goto keepBuffer;
}
if (statePtr->saveInBufPtr == NULL) {
statePtr->saveInBufPtr = bufPtr;
goto keepBuffer;
}
}
/*
* Only save buffers for the output queue if the channel is writable.
*/
if (GotFlag(statePtr, TCL_WRITABLE)) {
if (statePtr->curOutPtr == NULL) {
statePtr->curOutPtr = bufPtr;
goto keepBuffer;
}
}
/*
* If we reached this code we return the buffer to the OS.
*/
ReleaseChannelBuffer(bufPtr);
return;
keepBuffer:
bufPtr->nextRemoved = BUFFER_PADDING;
bufPtr->nextAdded = BUFFER_PADDING;
bufPtr->nextPtr = NULL;
}
/*
*----------------------------------------------------------------------
*
* DiscardOutputQueued --
*
* Discards all output queued in the output queue of a channel.
*
* Results:
* None.
*
* Side effects:
* Recycles buffers.
*
*----------------------------------------------------------------------
*/
static void
DiscardOutputQueued(
ChannelState *statePtr) /* ChannelState for which to discard output. */
{
ChannelBuffer *bufPtr;
while (statePtr->outQueueHead != NULL) {
bufPtr = statePtr->outQueueHead;
statePtr->outQueueHead = bufPtr->nextPtr;
RecycleBuffer(statePtr, bufPtr, 0);
}
statePtr->outQueueHead = NULL;
statePtr->outQueueTail = NULL;
bufPtr = statePtr->curOutPtr;
if (bufPtr && BytesLeft(bufPtr)) {
statePtr->curOutPtr = NULL;
RecycleBuffer(statePtr, bufPtr, 0);
}
}
/*
*----------------------------------------------------------------------
*
* CheckForDeadChannel --
*
* This function checks is a given channel is Dead (a channel that has
* been closed but not yet deallocated.)
*
* Results:
* True (1) if channel is Dead, False (0) if channel is Ok
*
* Side effects:
* None
*
*----------------------------------------------------------------------
*/
static int
CheckForDeadChannel(
Tcl_Interp *interp, /* For error reporting (can be NULL) */
ChannelState *statePtr) /* The channel state to check. */
{
if (!GotFlag(statePtr, CHANNEL_DEAD)) {
return 0;
}
Tcl_SetErrno(EINVAL);
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"unable to access channel: invalid channel", -1));
}
return 1;
}
/*
*----------------------------------------------------------------------
*
* FlushChannel --
*
* This function flushes as much of the queued output as is possible now.
* If calledFromAsyncFlush is nonzero, it is being called in an event
* handler to flush channel output asynchronously.
*
* Results:
* 0 if successful, else the error code that was returned by the channel
* type operation. May leave a message in the interp result.
*
* Side effects:
* May produce output on a channel. May block indefinitely if the channel
* is synchronous. May schedule an async flush on the channel. May
* recycle memory for buffers in the output queue.
*
*----------------------------------------------------------------------
*/
static int
FlushChannel(
Tcl_Interp *interp, /* For error reporting during close. */
Channel *chanPtr, /* The channel to flush on. */
int calledFromAsyncFlush) /* If nonzero then we are being called from an
* asynchronous flush callback. */
{
ChannelState *statePtr = chanPtr->state;
/* State of the channel stack. */
ChannelBuffer *bufPtr; /* Iterates over buffered output queue. */
int written; /* Amount of output data actually written in
* current round. */
int errorCode = 0; /* Stores POSIX error codes from channel
* driver operations. */
int wroteSome = 0; /* Set to one if any data was written to the
* driver. */
/*
* Prevent writing on a dead channel -- a channel that has been closed but
* not yet deallocated. This can occur if the exit handler for the channel
* deallocation runs before all channels are deregistered in all
* interpreters.
*/
if (CheckForDeadChannel(interp, statePtr)) {
return -1;
}
/*
* Should we shift the current output buffer over to the output queue?
* First check that there are bytes in it. If so then...
*
* If the output queue is empty, then yes, trusting the caller called us
* only when written bytes ought to be flushed.
*
* If the current output buffer is full, then yes, so we can meet the
* post-condition that on a successful return to caller we've left space
* in the current output buffer for more writing (the flush call was to
* make new room).
*
* If the channel is blocking, then yes, so we guarantee that blocking
* flushes actually flush all pending data.
*
* Otherwise, no. Keep the current output buffer where it is so more
* can be written to it, possibly filling it, to promote more efficient
* buffer usage.
*/
bufPtr = statePtr->curOutPtr;
if (bufPtr && BytesLeft(bufPtr) && /* Keep empties off queue */
(statePtr->outQueueHead == NULL || IsBufferFull(bufPtr)
|| !GotFlag(statePtr, CHANNEL_NONBLOCKING))) {
if (statePtr->outQueueHead == NULL) {
statePtr->outQueueHead = bufPtr;
} else {
statePtr->outQueueTail->nextPtr = bufPtr;
}
statePtr->outQueueTail = bufPtr;
statePtr->curOutPtr = NULL;
}
assert(!IsBufferFull(statePtr->curOutPtr));
/*
* If we are not being called from an async flush and an async flush
* is active, we just return without producing any output.
*/
if (!calledFromAsyncFlush && GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
return 0;
}
/*
* Loop over the queued buffers and attempt to flush as much as possible
* of the queued output to the channel.
*/
TclChannelPreserve((Tcl_Channel)chanPtr);
while (statePtr->outQueueHead) {
bufPtr = statePtr->outQueueHead;
/*
* Produce the output on the channel.
*/
PreserveChannelBuffer(bufPtr);
written = ChanWrite(chanPtr, RemovePoint(bufPtr), BytesLeft(bufPtr),
&errorCode);
/*
* If the write failed completely attempt to start the asynchronous
* flush mechanism and break out of this loop - do not attempt to
* write any more output at this time.
*/
if (written < 0) {
/*
* If the last attempt to write was interrupted, simply retry.
*/
if (errorCode == EINTR) {
errorCode = 0;
ReleaseChannelBuffer(bufPtr);
continue;
}
/*
* If the channel is non-blocking and we would have blocked, start
* a background flushing handler and break out of the loop.
*/
if ((errorCode == EWOULDBLOCK) || (errorCode == EAGAIN)) {
/*
* This used to check for CHANNEL_NONBLOCKING, and panic if
* the channel was blocking. However, it appears that setting
* stdin to -blocking 0 has some effect on the stdout when
* it's a tty channel (dup'ed underneath)
*/
if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED) && !TclInExit()) {
SetFlag(statePtr, BG_FLUSH_SCHEDULED);
UpdateInterest(chanPtr);
}
errorCode = 0;
ReleaseChannelBuffer(bufPtr);
break;
}
/*
* Decide whether to report the error upwards or defer it.
*/
if (calledFromAsyncFlush) {
/*
* TIP #219, Tcl Channel Reflection API.
* When defering the error copy a message from the bypass into
* the unreported area. Or discard it if the new error is to
* be ignored in favor of an earlier defered error.
*/
Tcl_Obj *msg = statePtr->chanMsg;
if (statePtr->unreportedError == 0) {
statePtr->unreportedError = errorCode;
statePtr->unreportedMsg = msg;
if (msg != NULL) {
Tcl_IncrRefCount(msg);
}
} else {
/*
* An old unreported error is kept, and this error thrown
* away.
*/
statePtr->chanMsg = NULL;
if (msg != NULL) {
TclDecrRefCount(msg);
}
}
} else {
/*
* TIP #219, Tcl Channel Reflection API.
* Move error messages put by the driver into the chan bypass
* area into the regular interpreter result. Fall back to the
* regular message if nothing was found in the bypasses.
*/
Tcl_SetErrno(errorCode);
if (interp != NULL && !TclChanCaughtErrorBypass(interp,
(Tcl_Channel) chanPtr)) {
Tcl_SetObjResult(interp,
Tcl_NewStringObj(Tcl_PosixError(interp), -1));
}
/*
* An unreportable bypassed message is kept, for the caller of
* Tcl_Seek, Tcl_Write, etc.
*/
}
/*
* When we get an error we throw away all the output currently
* queued.
*/
DiscardOutputQueued(statePtr);
ReleaseChannelBuffer(bufPtr);
break;
} else {
/*
* TODO: Consider detecting and reacting to short writes on
* blocking channels. Ought not happen. See iocmd-24.2.
*/
wroteSome = 1;
}
bufPtr->nextRemoved += written;
/*
* If this buffer is now empty, recycle it.
*/
if (IsBufferEmpty(bufPtr)) {
statePtr->outQueueHead = bufPtr->nextPtr;
if (statePtr->outQueueHead == NULL) {
statePtr->outQueueTail = NULL;
}
RecycleBuffer(statePtr, bufPtr, 0);
}
ReleaseChannelBuffer(bufPtr);
} /* Closes "while". */
/*
* If we wrote some data while flushing in the background, we are done.
* We can't finish the background flush until we run out of data and the
* channel becomes writable again. This ensures that all of the pending
* data has been flushed at the system level.
*/
if (GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
if (wroteSome) {
goto done;
} else if (statePtr->outQueueHead == NULL) {
ResetFlag(statePtr, BG_FLUSH_SCHEDULED);
ChanWatch(chanPtr, statePtr->interestMask);
} else {
/*
* When we are calledFromAsyncFlush, that means a writable
* state on the channel triggered the call, so we should be
* able to write something. Either we did write something
* and wroteSome should be set, or there was nothing left to
* write in this call, and we've completed the BG flush.
* These are the two cases above. If we get here, that means
* there is some kind failure in the writable event machinery.
*
* The tls extension indeed suffers from flaws in its channel
* event mgmt. See https://core.tcl-lang.org/tcl/info/c31ca233ca.
* Until that patch is broadly distributed, disable the
* assertion checking here, so that programs using Tcl and
* tls can be debugged.
assert(!calledFromAsyncFlush);
*/
}
}
/*
* If the channel is flagged as closed, delete it when the refCount drops
* to zero, the output queue is empty and there is no output in the
* current output buffer.
*/
if (GotFlag(statePtr, CHANNEL_CLOSED) && (statePtr->refCount <= 0) &&
(statePtr->outQueueHead == NULL) &&
((statePtr->curOutPtr == NULL) ||
IsBufferEmpty(statePtr->curOutPtr))) {
errorCode = CloseChannel(interp, chanPtr, errorCode);
goto done;
}
/*
* If the write-side of the channel is flagged as closed, delete it when
* the output queue is empty and there is no output in the current output
* buffer.
*/
if (GotFlag(statePtr, CHANNEL_CLOSEDWRITE) &&
(statePtr->outQueueHead == NULL) &&
((statePtr->curOutPtr == NULL) ||
IsBufferEmpty(statePtr->curOutPtr))) {
errorCode = CloseChannelPart(interp, chanPtr, errorCode,
TCL_CLOSE_WRITE);
goto done;
}
done:
TclChannelRelease((Tcl_Channel)chanPtr);
return errorCode;
}
/*
*----------------------------------------------------------------------
*
* CloseChannel --
*
* Utility procedure to close a channel and free associated resources.
*
* If the channel was stacked, then the it will copy the necessary
* elements of the NEXT channel into the TOP channel, in essence
* unstacking the channel. The NEXT channel will then be freed.
*
* If the channel was not stacked, then we will free all the bits for the
* TOP channel, including the data structure itself.
*
* Results:
* Error code from an unreported error or the driver close operation.
*
* Side effects:
* May close the actual channel, may free memory, may change the value of
* errno.
*
*----------------------------------------------------------------------
*/
static int
CloseChannel(
Tcl_Interp *interp, /* For error reporting. */
Channel *chanPtr, /* The channel to close. */
int errorCode) /* Status of operation so far. */
{
int result = 0; /* Of calling driver close operation. */
ChannelState *statePtr; /* State of the channel stack. */
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (chanPtr == NULL) {
return result;
}
statePtr = chanPtr->state;
/*
* No more input can be consumed so discard any leftover input.
*/
DiscardInputQueued(statePtr, 1);
/*
* Discard a leftover buffer in the current output buffer field.
*/
if (statePtr->curOutPtr != NULL) {
ReleaseChannelBuffer(statePtr->curOutPtr);
statePtr->curOutPtr = NULL;
}
/*
* The caller guarantees that there are no more buffers queued for output.
*/
if (statePtr->outQueueHead != NULL) {
Tcl_Panic("TclFlush, closed channel: queued output left");
}
/*
* If the EOF character is set in the channel, append that to the output
* device.
*/
if ((statePtr->outEofChar != 0) && GotFlag(statePtr, TCL_WRITABLE)) {
int dummy;
char c = (char) statePtr->outEofChar;
(void) ChanWrite(chanPtr, &c, 1, &dummy);
}
/*
* TIP #219, Tcl Channel Reflection API.
* Move a leftover error message in the channel bypass into the
* interpreter bypass. Just clear it if there is no interpreter.
*/
if (statePtr->chanMsg != NULL) {
if (interp != NULL) {
Tcl_SetChannelErrorInterp(interp, statePtr->chanMsg);
}
TclDecrRefCount(statePtr->chanMsg);
statePtr->chanMsg = NULL;
}
/*
* Remove this channel from of the list of all channels.
*/
CutChannel((Tcl_Channel) chanPtr);
/*
* Close and free the channel driver state.
* This may leave a TIP #219 error message in the interp.
*/
result = ChanClose(chanPtr, interp);
/*
* Some resources can be cleared only if the bottom channel in a stack is
* closed. All the other channels in the stack are not allowed to remove.
*/
if (chanPtr == statePtr->bottomChanPtr) {
if (statePtr->channelName != NULL) {
ckfree(statePtr->channelName);
statePtr->channelName = NULL;
}
Tcl_FreeEncoding(statePtr->encoding);
}
/*
* If we are being called synchronously, report either any latent error on
* the channel or the current error.
*/
if (statePtr->unreportedError != 0) {
errorCode = statePtr->unreportedError;
/*
* TIP #219, Tcl Channel Reflection API.
* Move an error message found in the unreported area into the regular
* bypass (interp). This kills any message in the channel bypass area.
*/
if (statePtr->chanMsg != NULL) {
TclDecrRefCount(statePtr->chanMsg);
statePtr->chanMsg = NULL;
}
if (interp) {
Tcl_SetChannelErrorInterp(interp, statePtr->unreportedMsg);
}
}
if (errorCode == 0) {
errorCode = result;
if (errorCode != 0) {
Tcl_SetErrno(errorCode);
}
}
/*
* Cancel any outstanding timer.
*/
Tcl_DeleteTimerHandler(statePtr->timer);
/*
* Mark the channel as deleted by clearing the type structure.
*/
if (chanPtr->downChanPtr != NULL) {
Channel *downChanPtr = chanPtr->downChanPtr;
statePtr->nextCSPtr = tsdPtr->firstCSPtr;
tsdPtr->firstCSPtr = statePtr;
statePtr->topChanPtr = downChanPtr;
downChanPtr->upChanPtr = NULL;
ChannelFree(chanPtr);
return Tcl_Close(interp, (Tcl_Channel) downChanPtr);
}
/*
* There is only the TOP Channel, so we free the remaining pointers we
* have and then ourselves. Since this is the last of the channels in the
* stack, make sure to free the ChannelState structure associated with it.
*/
ChannelFree(chanPtr);
Tcl_EventuallyFree(statePtr, TCL_DYNAMIC);
return errorCode;
}
/*
*----------------------------------------------------------------------
*
* Tcl_CutChannel --
* CutChannel --
*
* Removes a channel from the (thread-)global list of all channels (in
* that thread). This is actually the statePtr for the stack of channel.
*
* Results:
* Nothing.
*
* Side effects:
* Resets the field 'nextCSPtr' of the specified channel state to NULL.
*
* NOTE:
* The channel to cut out of the list must not be referenced in any
* interpreter. This is something this procedure cannot check (despite
* the refcount) because the caller usually wants fiddle with the channel
* (like transfering it to a different thread) and thus keeps the
* refcount artifically high to prevent its destruction.
*
*----------------------------------------------------------------------
*/
static void
CutChannel(
Tcl_Channel chan) /* The channel being removed. Must not be
* referenced in any interpreter. */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
ChannelState *prevCSPtr; /* Preceding channel state in list of all
* states - used to splice a channel out of
* the list on close. */
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of the channel stack. */
/*
* Remove this channel from of the list of all channels (in the current
* thread).
*/
if (tsdPtr->firstCSPtr && (statePtr == tsdPtr->firstCSPtr)) {
tsdPtr->firstCSPtr = statePtr->nextCSPtr;
} else {
for (prevCSPtr = tsdPtr->firstCSPtr;
prevCSPtr && (prevCSPtr->nextCSPtr != statePtr);
prevCSPtr = prevCSPtr->nextCSPtr) {
/* Empty loop body. */
}
if (prevCSPtr == NULL) {
Tcl_Panic("FlushChannel: damaged channel list");
}
prevCSPtr->nextCSPtr = statePtr->nextCSPtr;
}
statePtr->nextCSPtr = NULL;
/*
* TIP #218, Channel Thread Actions
*/
ChanThreadAction((Channel *) chan, TCL_CHANNEL_THREAD_REMOVE);
/* Channel is not managed by any thread */
statePtr->managingThread = NULL;
}
void
Tcl_CutChannel(
Tcl_Channel chan) /* The channel being added. Must not be
* referenced in any interpreter. */
{
Channel *chanPtr = ((Channel *) chan)->state->bottomChanPtr;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
ChannelState *prevCSPtr; /* Preceding channel state in list of all
* states - used to splice a channel out of
* the list on close. */
ChannelState *statePtr = chanPtr->state;
/* State of the channel stack. */
/*
* Remove this channel from of the list of all channels (in the current
* thread).
*/
if (tsdPtr->firstCSPtr && (statePtr == tsdPtr->firstCSPtr)) {
tsdPtr->firstCSPtr = statePtr->nextCSPtr;
} else {
for (prevCSPtr = tsdPtr->firstCSPtr;
prevCSPtr && (prevCSPtr->nextCSPtr != statePtr);
prevCSPtr = prevCSPtr->nextCSPtr) {
/* Empty loop body. */
}
if (prevCSPtr == NULL) {
Tcl_Panic("FlushChannel: damaged channel list");
}
prevCSPtr->nextCSPtr = statePtr->nextCSPtr;
}
statePtr->nextCSPtr = NULL;
/*
* TIP #218, Channel Thread Actions
* For all transformations and the base channel.
*/
for (; chanPtr != NULL ; chanPtr = chanPtr->upChanPtr) {
ChanThreadAction(chanPtr, TCL_CHANNEL_THREAD_REMOVE);
}
/* Channel is not managed by any thread */
statePtr->managingThread = NULL;
}
/*
*----------------------------------------------------------------------
*
* Tcl_SpliceChannel --
* SpliceChannel --
*
* Adds a channel to the (thread-)global list of all channels (in that
* thread). Expects that the field 'nextChanPtr' in the channel is set to
* NULL.
*
* Results:
* Nothing.
*
* Side effects:
* Nothing.
*
* NOTE:
* The channel to splice into the list must not be referenced in any
* interpreter. This is something this procedure cannot check (despite
* the refcount) because the caller usually wants figgle with the channel
* (like transfering it to a different thread) and thus keeps the
* refcount artifically high to prevent its destruction.
*
*----------------------------------------------------------------------
*/
static void
SpliceChannel(
Tcl_Channel chan) /* The channel being added. Must not be
* referenced in any interpreter. */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
ChannelState *statePtr = ((Channel *) chan)->state;
if (statePtr->nextCSPtr != NULL) {
Tcl_Panic("SpliceChannel: trying to add channel used in different list");
}
statePtr->nextCSPtr = tsdPtr->firstCSPtr;
tsdPtr->firstCSPtr = statePtr;
/*
* TIP #10. Mark the current thread as the new one managing this channel.
* Note: 'Tcl_GetCurrentThread' returns sensible values even for
* a non-threaded core.
*/
statePtr->managingThread = Tcl_GetCurrentThread();
/*
* TIP #218, Channel Thread Actions
*/
ChanThreadAction((Channel *) chan, TCL_CHANNEL_THREAD_INSERT);
}
void
Tcl_SpliceChannel(
Tcl_Channel chan) /* The channel being added. Must not be
* referenced in any interpreter. */
{
Channel *chanPtr = ((Channel *) chan)->state->bottomChanPtr;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
ChannelState *statePtr = chanPtr->state;
if (statePtr->nextCSPtr != NULL) {
Tcl_Panic("SpliceChannel: trying to add channel used in different list");
}
statePtr->nextCSPtr = tsdPtr->firstCSPtr;
tsdPtr->firstCSPtr = statePtr;
/*
* TIP #10. Mark the current thread as the new one managing this channel.
* Note: 'Tcl_GetCurrentThread' returns sensible values even for
* a non-threaded core.
*/
statePtr->managingThread = Tcl_GetCurrentThread();
/*
* TIP #218, Channel Thread Actions
* For all transformations and the base channel.
*/
for (; chanPtr != NULL ; chanPtr = chanPtr->upChanPtr) {
ChanThreadAction(chanPtr, TCL_CHANNEL_THREAD_INSERT);
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_Close --
*
* Closes a channel.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* Closes the channel if this is the last reference.
*
* NOTE:
* Tcl_Close removes the channel as far as the user is concerned.
* However, it may continue to exist for a while longer if it has a
* background flush scheduled. The device itself is eventually closed and
* the channel record removed, in CloseChannel, above.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_Close(
Tcl_Interp *interp, /* Interpreter for errors. */
Tcl_Channel chan) /* The channel being closed. Must not be
* referenced in any interpreter. */
{
CloseCallback *cbPtr; /* Iterate over close callbacks for this
* channel. */
Channel *chanPtr; /* The real IO channel. */
ChannelState *statePtr; /* State of real IO channel. */
int result = 0; /* Of calling FlushChannel. */
int flushcode;
int stickyError;
if (chan == NULL) {
return TCL_OK;
}
/*
* Perform special handling for standard channels being closed. If the
* refCount is now 1 it means that the last reference to the standard
* channel is being explicitly closed, so bump the refCount down
* artificially to 0. This will ensure that the channel is actually
* closed, below. Also set the static pointer to NULL for the channel.
*/
CheckForStdChannelsBeingClosed(chan);
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = (Channel *) chan;
statePtr = chanPtr->state;
chanPtr = statePtr->topChanPtr;
if (statePtr->refCount > 0) {
Tcl_Panic("called Tcl_Close on channel with refCount > 0");
}
if (GotFlag(statePtr, CHANNEL_INCLOSE)) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"illegal recursive call to close through close-handler"
" of channel", -1));
}
return TCL_ERROR;
}
SetFlag(statePtr, CHANNEL_INCLOSE);
/*
* When the channel has an escape sequence driven encoding such as
* iso2022, the terminated escape sequence must write to the buffer.
*/
stickyError = 0;
if (GotFlag(statePtr, TCL_WRITABLE) && (statePtr->encoding != NULL)
&& !(statePtr->outputEncodingFlags & TCL_ENCODING_START)) {
int code = CheckChannelErrors(statePtr, TCL_WRITABLE);
if (code == 0) {
statePtr->outputEncodingFlags |= TCL_ENCODING_END;
code = WriteChars(chanPtr, "", 0);
statePtr->outputEncodingFlags &= ~TCL_ENCODING_END;
statePtr->outputEncodingFlags |= TCL_ENCODING_START;
}
if (code < 0) {
stickyError = Tcl_GetErrno();
}
/*
* TIP #219, Tcl Channel Reflection API.
* Move an error message found in the channel bypass into the
* interpreter bypass. Just clear it if there is no interpreter.
*/
if (statePtr->chanMsg != NULL) {
if (interp != NULL) {
Tcl_SetChannelErrorInterp(interp, statePtr->chanMsg);
}
TclDecrRefCount(statePtr->chanMsg);
statePtr->chanMsg = NULL;
}
}
Tcl_ClearChannelHandlers(chan);
/*
* Invoke the registered close callbacks and delete their records.
*/
while (statePtr->closeCbPtr != NULL) {
cbPtr = statePtr->closeCbPtr;
statePtr->closeCbPtr = cbPtr->nextPtr;
cbPtr->proc(cbPtr->clientData);
ckfree(cbPtr);
}
ResetFlag(statePtr, CHANNEL_INCLOSE);
/*
* If this channel supports it, close the read side, since we don't need
* it anymore and this will help avoid deadlocks on some channel types.
*/
if (chanPtr->typePtr->closeProc == TCL_CLOSE2PROC) {
result = chanPtr->typePtr->close2Proc(chanPtr->instanceData, interp,
TCL_CLOSE_READ);
if ((result == EINVAL) || result == ENOTCONN) {
result = 0;
}
}
/*
* The call to FlushChannel will flush any queued output and invoke the
* close function of the channel driver, or it will set up the channel to
* be flushed and closed asynchronously.
*/
SetFlag(statePtr, CHANNEL_CLOSED);
flushcode = FlushChannel(interp, chanPtr, 0);
/*
* TIP #219.
* Capture error messages put by the driver into the bypass area and put
* them into the regular interpreter result.
*
* Notes: Due to the assertion of CHANNEL_CLOSED in the flags
* FlushChannel() has called CloseChannel() and thus freed all the channel
* structures. We must not try to access "chan" anymore, hence the NULL
* argument in the call below. The only place which may still contain a
* message is the interpreter itself, and "CloseChannel" made sure to lift
* any channel message it generated into it.
*/
if (TclChanCaughtErrorBypass(interp, NULL)) {
result = EINVAL;
}
if (stickyError != 0) {
Tcl_SetErrno(stickyError);
if (interp != NULL) {
Tcl_SetObjResult(interp,
Tcl_NewStringObj(Tcl_PosixError(interp), -1));
}
return TCL_ERROR;
}
/*
* Bug 97069ea11a: set error message if a flush code is set and no error
* message set up to now.
*/
if (flushcode != 0) {
/* flushcode has precedence, if available */
result = flushcode;
}
if ((result != 0) && (result != TCL_ERROR) && (interp != NULL)
&& 0 == Tcl_GetCharLength(Tcl_GetObjResult(interp))) {
Tcl_SetErrno(result);
Tcl_SetObjResult(interp,
Tcl_NewStringObj(Tcl_PosixError(interp), -1));
}
if (result != 0) {
return TCL_ERROR;
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_CloseEx --
*
* Closes one side of a channel, read or write.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* Closes one direction of the channel.
*
* NOTE:
* Tcl_CloseEx closes the specified direction of the channel as far as
* the user is concerned. The channel keeps existing however. You cannot
* call this function to close the last possible direction of the
* channel. Use Tcl_Close for that.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_CloseEx(
Tcl_Interp *interp, /* Interpreter for errors. */
Tcl_Channel chan, /* The channel being closed. May still be used
* by some interpreter. */
int flags) /* Flags telling us which side to close. */
{
Channel *chanPtr; /* The real IO channel. */
ChannelState *statePtr; /* State of real IO channel. */
if (chan == NULL) {
return TCL_OK;
}
chanPtr = (Channel *) chan;
statePtr = chanPtr->state;
if ((flags & (TCL_READABLE | TCL_WRITABLE)) == 0) {
return Tcl_Close(interp, chan);
}
if ((flags & (TCL_READABLE | TCL_WRITABLE)) == (TCL_READABLE | TCL_WRITABLE)) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"double-close of channels not supported by %ss",
chanPtr->typePtr->typeName));
return TCL_ERROR;
}
/*
* Does the channel support half-close anyway? Error if not.
*/
if (!chanPtr->typePtr->close2Proc) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"half-close of channels not supported by %ss",
chanPtr->typePtr->typeName));
return TCL_ERROR;
}
/*
* Is the channel unstacked ? If not we fail.
*/
if (chanPtr != statePtr->topChanPtr) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"half-close not applicable to stack of transformations", -1));
return TCL_ERROR;
}
/*
* Check direction against channel mode. It is an error if we try to close
* a direction not supported by the channel (already closed, or never
* opened for that direction).
*/
if (!(statePtr->flags & (TCL_READABLE | TCL_WRITABLE) & flags)) {
const char *msg;
if (flags & TCL_CLOSE_READ) {
msg = "read";
} else {
msg = "write";
}
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"Half-close of %s-side not possible, side not opened or"
" already closed", msg));
return TCL_ERROR;
}
/*
* A user may try to call half-close from within a channel close handler.
* That won't do.
*/
if (statePtr->flags & CHANNEL_INCLOSE) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"illegal recursive call to close through close-handler"
" of channel", -1));
}
return TCL_ERROR;
}
if (flags & TCL_CLOSE_READ) {
/*
* Call the finalization code directly. There are no events to handle,
* there cannot be for the read-side.
*/
return CloseChannelPart(interp, chanPtr, 0, flags);
} else if (flags & TCL_CLOSE_WRITE) {
Tcl_Preserve(statePtr);
if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
/*
* We don't want to re-enter CloseWrite().
*/
if (!GotFlag(statePtr, CHANNEL_CLOSEDWRITE)) {
if (CloseWrite(interp, chanPtr) != TCL_OK) {
SetFlag(statePtr, CHANNEL_CLOSEDWRITE);
Tcl_Release(statePtr);
return TCL_ERROR;
}
}
}
SetFlag(statePtr, CHANNEL_CLOSEDWRITE);
Tcl_Release(statePtr);
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* CloseWrite --
*
* Closes the write side a channel.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* Closes the write side of the channel.
*
* NOTE:
* CloseWrite removes the channel as far as the user is concerned.
* However, the ooutput data structures may continue to exist for a while
* longer if it has a background flush scheduled. The device itself is
* eventually closed and the channel structures modified, in
* CloseChannelPart, below.
*
*----------------------------------------------------------------------
*/
static int
CloseWrite(
Tcl_Interp *interp, /* Interpreter for errors. */
Channel *chanPtr) /* The channel whose write side is being
* closed. May still be used by some
* interpreter */
{
/*
* Notes: clear-channel-handlers - write side only ? or keep around, just
* not called.
*
* No close callbacks are run - channel is still open (read side)
*/
ChannelState *statePtr = chanPtr->state;
/* State of real IO channel. */
int flushcode;
int result = 0;
/*
* The call to FlushChannel will flush any queued output and invoke the
* close function of the channel driver, or it will set up the channel to
* be flushed and closed asynchronously.
*/
SetFlag(statePtr, CHANNEL_CLOSEDWRITE);
flushcode = FlushChannel(interp, chanPtr, 0);
/*
* TIP #219.
* Capture error messages put by the driver into the bypass area and put
* them into the regular interpreter result.
*
* Notes: Due to the assertion of CHANNEL_CLOSEDWRITE in the flags
* FlushChannel() has called CloseChannelPart(). While we can still access
* "chan" (no structures were freed), the only place which may still
* contain a message is the interpreter itself, and "CloseChannelPart"
* made sure to lift any channel message it generated into it. Hence the
* NULL argument in the call below.
*/
if (TclChanCaughtErrorBypass(interp, NULL)) {
result = EINVAL;
}
if ((flushcode != 0) || (result != 0)) {
return TCL_ERROR;
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* CloseChannelPart --
*
* Utility procedure to close a channel partially and free associated
* resources. If the channel was stacked it will never be run (The higher
* level forbid this). If the channel was not stacked, then we will free
* all the bits of the chosen side (read, or write) for the TOP channel.
*
* Results:
* Error code from an unreported error or the driver close2 operation.
*
* Side effects:
* May free memory, may change the value of errno.
*
*----------------------------------------------------------------------
*/
static int
CloseChannelPart(
Tcl_Interp *interp, /* Interpreter for errors. */
Channel *chanPtr, /* The channel being closed. May still be used
* by some interpreter. */
int errorCode, /* Status of operation so far. */
int flags) /* Flags telling us which side to close. */
{
ChannelState *statePtr; /* State of real IO channel. */
int result; /* Of calling the close2proc. */
statePtr = chanPtr->state;
if (flags & TCL_CLOSE_READ) {
/*
* No more input can be consumed so discard any leftover input.
*/
DiscardInputQueued(statePtr, 1);
} else if (flags & TCL_CLOSE_WRITE) {
/*
* The caller guarantees that there are no more buffers queued for
* output.
*/
if (statePtr->outQueueHead != NULL) {
Tcl_Panic("ClosechanHalf, closed write-side of channel: "
"queued output left");
}
/*
* If the EOF character is set in the channel, append that to the
* output device.
*/
if ((statePtr->outEofChar != 0) && GotFlag(statePtr, TCL_WRITABLE)) {
int dummy;
char c = (char) statePtr->outEofChar;
(void) ChanWrite(chanPtr, &c, 1, &dummy);
}
/*
* TIP #219, Tcl Channel Reflection API.
* Move a leftover error message in the channel bypass into the
* interpreter bypass. Just clear it if there is no interpreter.
*/
if (statePtr->chanMsg != NULL) {
if (interp != NULL) {
Tcl_SetChannelErrorInterp(interp, statePtr->chanMsg);
}
TclDecrRefCount(statePtr->chanMsg);
statePtr->chanMsg = NULL;
}
}
/*
* Finally do what is asked of us. Close and free the channel driver state
* for the chosen side of the channel. This may leave a TIP #219 error
* message in the interp.
*/
result = chanPtr->typePtr->close2Proc(chanPtr->instanceData, NULL, flags);
/*
* If we are being called synchronously, report either any latent error on
* the channel or the current error.
*/
if (statePtr->unreportedError != 0) {
errorCode = statePtr->unreportedError;
/*
* TIP #219, Tcl Channel Reflection API.
* Move an error message found in the unreported area into the regular
* bypass (interp). This kills any message in the channel bypass area.
*/
if (statePtr->chanMsg != NULL) {
TclDecrRefCount(statePtr->chanMsg);
statePtr->chanMsg = NULL;
}
if (interp) {
Tcl_SetChannelErrorInterp(interp, statePtr->unreportedMsg);
}
}
if (errorCode == 0) {
errorCode = result;
if (errorCode != 0) {
Tcl_SetErrno(errorCode);
}
}
/*
* TIP #219.
* Capture error messages put by the driver into the bypass area and put
* them into the regular interpreter result. See also the bottom of
* CloseWrite().
*/
if (TclChanCaughtErrorBypass(interp, (Tcl_Channel) chanPtr)) {
result = EINVAL;
}
if (result != 0) {
return TCL_ERROR;
}
/*
* Remove the closed side from the channel mode/flags.
*/
ResetFlag(statePtr, flags & (TCL_READABLE | TCL_WRITABLE));
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ClearChannelHandlers --
*
* Removes all channel handlers and event scripts from the channel,
* cancels all background copies involving the channel and any interest
* in events.
*
* Results:
* None.
*
* Side effects:
* See above. Deallocates memory.
*
*----------------------------------------------------------------------
*/
void
Tcl_ClearChannelHandlers(
Tcl_Channel channel)
{
ChannelHandler *chPtr, *chNext; /* Iterate over channel handlers. */
EventScriptRecord *ePtr, *eNextPtr; /* Iterate over eventscript records. */
Channel *chanPtr; /* The real IO channel. */
ChannelState *statePtr; /* State of real IO channel. */
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
NextChannelHandler *nhPtr;
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = (Channel *) channel;
statePtr = chanPtr->state;
chanPtr = statePtr->topChanPtr;
/*
* Cancel any outstanding timer.
*/
Tcl_DeleteTimerHandler(statePtr->timer);
/*
* Remove any references to channel handlers for this channel that may be
* about to be invoked.
*/
for (nhPtr = tsdPtr->nestedHandlerPtr; nhPtr != NULL;
nhPtr = nhPtr->nestedHandlerPtr) {
if (nhPtr->nextHandlerPtr &&
(nhPtr->nextHandlerPtr->chanPtr == chanPtr)) {
nhPtr->nextHandlerPtr = NULL;
}
}
/*
* Remove all the channel handler records attached to the channel itself.
*/
for (chPtr = statePtr->chPtr; chPtr != NULL; chPtr = chNext) {
chNext = chPtr->nextPtr;
ckfree(chPtr);
}
statePtr->chPtr = NULL;
/*
* Cancel any pending copy operation.
*/
StopCopy(statePtr->csPtrR);
StopCopy(statePtr->csPtrW);
/*
* Must set the interest mask now to 0, otherwise infinite loops will
* occur if Tcl_DoOneEvent is called before the channel is finally deleted
* in FlushChannel. This can happen if the channel has a background flush
* active.
*/
statePtr->interestMask = 0;
/*
* Remove any EventScript records for this channel.
*/
for (ePtr = statePtr->scriptRecordPtr; ePtr != NULL; ePtr = eNextPtr) {
eNextPtr = ePtr->nextPtr;
TclDecrRefCount(ePtr->scriptPtr);
ckfree(ePtr);
}
statePtr->scriptRecordPtr = NULL;
}
/*
*----------------------------------------------------------------------
*
* Tcl_Write --
*
* Puts a sequence of bytes into an output buffer, may queue the buffer
* for output if it gets full, and also remembers whether the current
* buffer is ready e.g. if it contains a newline and we are in line
* buffering mode. Compensates stacking, i.e. will redirect the data from
* the specified channel to the topmost channel in a stack.
*
* No encoding conversions are applied to the bytes being read.
*
* Results:
* The number of bytes written or -1 in case of error. If -1,
* Tcl_GetErrno will return the error code.
*
* Side effects:
* May buffer up output and may cause output to be produced on the
* channel.
*
*----------------------------------------------------------------------
*/
int
Tcl_Write(
Tcl_Channel chan, /* The channel to buffer output for. */
const char *src, /* Data to queue in output buffer. */
int srcLen) /* Length of data in bytes, or < 0 for
* strlen(). */
{
/*
* Always use the topmost channel of the stack
*/
Channel *chanPtr;
ChannelState *statePtr; /* State info for channel */
statePtr = ((Channel *) chan)->state;
chanPtr = statePtr->topChanPtr;
if (CheckChannelErrors(statePtr, TCL_WRITABLE) != 0) {
return -1;
}
if (srcLen < 0) {
srcLen = strlen(src);
}
if (WriteBytes(chanPtr, src, srcLen) < 0) {
return -1;
}
return srcLen;
}
/*
*----------------------------------------------------------------------
*
* Tcl_WriteRaw --
*
* Puts a sequence of bytes into an output buffer, may queue the buffer
* for output if it gets full, and also remembers whether the current
* buffer is ready e.g. if it contains a newline and we are in line
* buffering mode. Writes directly to the driver of the channel, does not
* compensate for stacking.
*
* No encoding conversions are applied to the bytes being read.
*
* Results:
* The number of bytes written or -1 in case of error. If -1,
* Tcl_GetErrno will return the error code.
*
* Side effects:
* May buffer up output and may cause output to be produced on the
* channel.
*
*----------------------------------------------------------------------
*/
int
Tcl_WriteRaw(
Tcl_Channel chan, /* The channel to buffer output for. */
const char *src, /* Data to queue in output buffer. */
int srcLen) /* Length of data in bytes, or < 0 for
* strlen(). */
{
Channel *chanPtr = ((Channel *) chan);
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
int errorCode, written;
if (CheckChannelErrors(statePtr, TCL_WRITABLE | CHANNEL_RAW_MODE) != 0) {
return -1;
}
if (srcLen < 0) {
srcLen = strlen(src);
}
/*
* Go immediately to the driver, do all the error handling by ourselves.
* The code was stolen from 'FlushChannel'.
*/
written = ChanWrite(chanPtr, src, srcLen, &errorCode);
if (written < 0) {
Tcl_SetErrno(errorCode);
}
return written;
}
/*
*---------------------------------------------------------------------------
*
* Tcl_WriteChars --
*
* Takes a sequence of UTF-8 characters and converts them for output
* using the channel's current encoding, may queue the buffer for output
* if it gets full, and also remembers whether the current buffer is
* ready e.g. if it contains a newline and we are in line buffering
* mode. Compensates stacking, i.e. will redirect the data from the
* specified channel to the topmost channel in a stack.
*
* Results:
* The number of bytes written or -1 in case of error. If -1,
* Tcl_GetErrno will return the error code.
*
* Side effects:
* May buffer up output and may cause output to be produced on the
* channel.
*
*----------------------------------------------------------------------
*/
int
Tcl_WriteChars(
Tcl_Channel chan, /* The channel to buffer output for. */
const char *src, /* UTF-8 characters to queue in output
* buffer. */
int len) /* Length of string in bytes, or < 0 for
* strlen(). */
{
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state; /* State info for channel */
int result;
Tcl_Obj *objPtr;
if (CheckChannelErrors(statePtr, TCL_WRITABLE) != 0) {
return -1;
}
chanPtr = statePtr->topChanPtr;
if (len < 0) {
len = strlen(src);
}
if (statePtr->encoding) {
return WriteChars(chanPtr, src, len);
}
/*
* Inefficient way to convert UTF-8 to byte-array, but the code
* parallels the way it is done for objects. Special case for 1-byte
* (used by eg [puts] for the \n) could be extended to more efficient
* translation of the src string.
*/
if ((len == 1) && (UCHAR(*src) < 0xC0)) {
return WriteBytes(chanPtr, src, len);
}
objPtr = Tcl_NewStringObj(src, len);
src = (char *) Tcl_GetByteArrayFromObj(objPtr, &len);
result = WriteBytes(chanPtr, src, len);
TclDecrRefCount(objPtr);
return result;
}
/*
*---------------------------------------------------------------------------
*
* Tcl_WriteObj --
*
* Takes the Tcl object and queues its contents for output. If the
* encoding of the channel is NULL, takes the byte-array representation
* of the object and queues those bytes for output. Otherwise, takes the
* characters in the UTF-8 (string) representation of the object and
* converts them for output using the channel's current encoding. May
* flush internal buffers to output if one becomes full or is ready for
* some other reason, e.g. if it contains a newline and the channel is in
* line buffering mode.
*
* Results:
* The number of bytes written or -1 in case of error. If -1,
* Tcl_GetErrno() will return the error code.
*
* Side effects:
* May buffer up output and may cause output to be produced on the
* channel.
*
*----------------------------------------------------------------------
*/
int
Tcl_WriteObj(
Tcl_Channel chan, /* The channel to buffer output for. */
Tcl_Obj *objPtr) /* The object to write. */
{
/*
* Always use the topmost channel of the stack
*/
Channel *chanPtr;
ChannelState *statePtr; /* State info for channel */
const char *src;
int srcLen;
statePtr = ((Channel *) chan)->state;
chanPtr = statePtr->topChanPtr;
if (CheckChannelErrors(statePtr, TCL_WRITABLE) != 0) {
return -1;
}
if (statePtr->encoding == NULL) {
src = (char *) Tcl_GetByteArrayFromObj(objPtr, &srcLen);
return WriteBytes(chanPtr, src, srcLen);
} else {
src = TclGetStringFromObj(objPtr, &srcLen);
return WriteChars(chanPtr, src, srcLen);
}
}
static void
WillWrite(
Channel *chanPtr)
{
int inputBuffered;
if ((Tcl_ChannelSeekProc(chanPtr->typePtr) != NULL) &&
((inputBuffered = Tcl_InputBuffered((Tcl_Channel) chanPtr)) > 0)){
int ignore;
DiscardInputQueued(chanPtr->state, 0);
ChanSeek(chanPtr, -inputBuffered, SEEK_CUR, &ignore);
}
}
static int
WillRead(
Channel *chanPtr)
{
if (chanPtr->typePtr == NULL) {
/*
* Prevent read attempts on a closed channel.
*/
DiscardInputQueued(chanPtr->state, 0);
Tcl_SetErrno(EINVAL);
return -1;
}
if ((Tcl_ChannelSeekProc(chanPtr->typePtr) != NULL)
&& (Tcl_OutputBuffered((Tcl_Channel) chanPtr) > 0)) {
/*
* CAVEAT - The assumption here is that FlushChannel() will push out
* the bytes of any writes that are in progress. Since this is a
* seekable channel, we assume it is not one that can block and force
* bg flushing. Channels we know that can do that - sockets, pipes -
* are not seekable. If the assumption is wrong, more drastic measures
* may be required here like temporarily setting the channel into
* blocking mode.
*/
if (FlushChannel(NULL, chanPtr, 0) != 0) {
return -1;
}
}
return 0;
}
/*
*----------------------------------------------------------------------
*
* Write --
*
* Convert srcLen bytes starting at src according to encoding and write
* produced bytes into an output buffer, may queue the buffer for output
* if it gets full, and also remembers whether the current buffer is
* ready e.g. if it contains a newline and we are in line buffering mode.
*
* Results:
* The number of bytes written or -1 in case of error. If -1,
* Tcl_GetErrno will return the error code.
*
* Side effects:
* May buffer up output and may cause output to be produced on the
* channel.
*
*----------------------------------------------------------------------
*/
static int
Write(
Channel *chanPtr, /* The channel to buffer output for. */
const char *src, /* UTF-8 string to write. */
int srcLen, /* Length of UTF-8 string in bytes. */
Tcl_Encoding encoding)
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
char *nextNewLine = NULL;
int endEncoding, saved = 0, total = 0, flushed = 0, needNlFlush = 0;
char safe[BUFFER_PADDING];
if (srcLen) {
WillWrite(chanPtr);
}
/*
* Write the terminated escape sequence even if srcLen is 0.
*/
endEncoding = ((statePtr->outputEncodingFlags & TCL_ENCODING_END) != 0);
if (GotFlag(statePtr, CHANNEL_LINEBUFFERED)
|| (statePtr->outputTranslation != TCL_TRANSLATE_LF)) {
nextNewLine = (char *)memchr(src, '\n', srcLen);
}
while (srcLen + saved + endEncoding > 0) {
ChannelBuffer *bufPtr;
char *dst;
int result, srcRead, dstLen, dstWrote, srcLimit = srcLen;
if (nextNewLine) {
srcLimit = nextNewLine - src;
}
/* Get space to write into */
bufPtr = statePtr->curOutPtr;
if (bufPtr == NULL) {
bufPtr = AllocChannelBuffer(statePtr->bufSize);
statePtr->curOutPtr = bufPtr;
}
if (saved) {
/*
* Here's some translated bytes left over from the last buffer
* that we need to stick at the beginning of this buffer.
*/
memcpy(InsertPoint(bufPtr), safe, saved);
bufPtr->nextAdded += saved;
saved = 0;
}
PreserveChannelBuffer(bufPtr);
dst = InsertPoint(bufPtr);
dstLen = SpaceLeft(bufPtr);
result = Tcl_UtfToExternal(NULL, encoding, src, srcLimit,
statePtr->outputEncodingFlags,
&statePtr->outputEncodingState, dst,
dstLen + BUFFER_PADDING, &srcRead, &dstWrote, NULL);
/*
* See chan-io-1.[89]. Tcl Bug 506297.
*/
statePtr->outputEncodingFlags &= ~TCL_ENCODING_START;
if ((result != TCL_OK) && (srcRead + dstWrote == 0)) {
/*
* We're reading from invalid/incomplete UTF-8.
*/
ReleaseChannelBuffer(bufPtr);
if (total == 0) {
Tcl_SetErrno(EINVAL);
return -1;
}
break;
}
bufPtr->nextAdded += dstWrote;
src += srcRead;
srcLen -= srcRead;
total += dstWrote;
dst += dstWrote;
dstLen -= dstWrote;
if (src == nextNewLine && dstLen > 0) {
static char crln[3] = "\r\n";
char *nl = NULL;
int nlLen = 0;
switch (statePtr->outputTranslation) {
case TCL_TRANSLATE_LF:
nl = crln + 1;
nlLen = 1;
break;
case TCL_TRANSLATE_CR:
nl = crln;
nlLen = 1;
break;
case TCL_TRANSLATE_CRLF:
nl = crln;
nlLen = 2;
break;
default:
Tcl_Panic("unknown output translation requested");
break;
}
result |= Tcl_UtfToExternal(NULL, encoding, nl, nlLen,
statePtr->outputEncodingFlags,
&statePtr->outputEncodingState, dst,
dstLen + BUFFER_PADDING, &srcRead, &dstWrote, NULL);
assert(srcRead == nlLen);
bufPtr->nextAdded += dstWrote;
src++;
srcLen--;
total += dstWrote;
dst += dstWrote;
dstLen -= dstWrote;
nextNewLine = (char *)memchr(src, '\n', srcLen);
needNlFlush = 1;
}
if (IsBufferOverflowing(bufPtr)) {
/*
* When translating from UTF-8 to external encoding, we allowed
* the translation to produce a character that crossed the end of
* the output buffer, so that we would get a completely full
* buffer before flushing it. The extra bytes will be moved to the
* beginning of the next buffer.
*/
saved = -SpaceLeft(bufPtr);
memcpy(safe, dst + dstLen, saved);
bufPtr->nextAdded = bufPtr->bufLength;
}
if ((srcLen + saved == 0) && (result == TCL_OK)) {
endEncoding = 0;
}
if (IsBufferFull(bufPtr)) {
if (FlushChannel(NULL, chanPtr, 0) != 0) {
ReleaseChannelBuffer(bufPtr);
return -1;
}
flushed += statePtr->bufSize;
/*
* We just flushed. So if we have needNlFlush set to record that
* we need to flush because theres a (translated) newline in the
* buffer, that's likely not true any more. But there is a tricky
* exception. If we have saved bytes that did not really get
* flushed and those bytes came from a translation of a newline as
* the last thing taken from the src array, then needNlFlush needs
* to remain set to flag that the next buffer still needs a
* newline flush.
*/
if (needNlFlush && (saved == 0 || src[-1] != '\n')) {
needNlFlush = 0;
}
}
ReleaseChannelBuffer(bufPtr);
}
if ((flushed < total) && (GotFlag(statePtr, CHANNEL_UNBUFFERED) ||
(needNlFlush && GotFlag(statePtr, CHANNEL_LINEBUFFERED)))) {
if (FlushChannel(NULL, chanPtr, 0) != 0) {
return -1;
}
}
return total;
}
/*
*---------------------------------------------------------------------------
*
* Tcl_Gets --
*
* Reads a complete line of input from the channel into a Tcl_DString.
*
* Results:
* Length of line read (in characters) or -1 if error, EOF, or blocked.
* If -1, use Tcl_GetErrno() to retrieve the POSIX error code for the
* error or condition that occurred.
*
* Side effects:
* May flush output on the channel. May cause input to be consumed from
* the channel.
*
*---------------------------------------------------------------------------
*/
int
Tcl_Gets(
Tcl_Channel chan, /* Channel from which to read. */
Tcl_DString *lineRead) /* The line read will be appended to this
* DString as UTF-8 characters. The caller
* must have initialized it and is responsible
* for managing the storage. */
{
Tcl_Obj *objPtr;
int charsStored;
TclNewObj(objPtr);
charsStored = Tcl_GetsObj(chan, objPtr);
if (charsStored > 0) {
TclDStringAppendObj(lineRead, objPtr);
}
TclDecrRefCount(objPtr);
return charsStored;
}
/*
*---------------------------------------------------------------------------
*
* Tcl_GetsObj --
*
* Accumulate input from the input channel until end-of-line or
* end-of-file has been seen. Bytes read from the input channel are
* converted to UTF-8 using the encoding specified by the channel.
*
* Results:
* Number of characters accumulated in the object or -1 if error,
* blocked, or EOF. If -1, use Tcl_GetErrno() to retrieve the POSIX error
* code for the error or condition that occurred.
*
* Side effects:
* Consumes input from the channel.
*
* On reading EOF, leave channel pointing at EOF char. On reading EOL,
* leave channel pointing after EOL, but don't return EOL in dst buffer.
*
*---------------------------------------------------------------------------
*/
int
Tcl_GetsObj(
Tcl_Channel chan, /* Channel from which to read. */
Tcl_Obj *objPtr) /* The line read will be appended to this
* object as UTF-8 characters. */
{
GetsState gs;
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
ChannelBuffer *bufPtr;
int inEofChar, skip, copiedTotal, oldLength, oldFlags, oldRemoved;
Tcl_Encoding encoding;
char *dst, *dstEnd, *eol, *eof;
Tcl_EncodingState oldState;
if (CheckChannelErrors(statePtr, TCL_READABLE) != 0) {
return -1;
}
/*
* If we're sitting ready to read the eofchar, there's no need to
* do it.
*/
if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) {
SetFlag(statePtr, CHANNEL_EOF);
assert(statePtr->inputEncodingFlags & TCL_ENCODING_END);
assert(!GotFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR));
/* TODO: Do we need this? */
UpdateInterest(chanPtr);
return -1;
}
/*
* A binary version of Tcl_GetsObj. This could also handle encodings that
* are ascii-7 pure (iso8859, utf-8, ...) with a final encoding conversion
* done on objPtr.
*/
if ((statePtr->encoding == NULL)
&& ((statePtr->inputTranslation == TCL_TRANSLATE_LF)
|| (statePtr->inputTranslation == TCL_TRANSLATE_CR))) {
return TclGetsObjBinary(chan, objPtr);
}
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
bufPtr = statePtr->inQueueHead;
encoding = statePtr->encoding;
/*
* Preserved so we can restore the channel's state in case we don't find a
* newline in the available input.
*/
TclGetStringFromObj(objPtr, &oldLength);
oldFlags = statePtr->inputEncodingFlags;
oldState = statePtr->inputEncodingState;
oldRemoved = BUFFER_PADDING;
if (bufPtr != NULL) {
oldRemoved = bufPtr->nextRemoved;
}
/*
* If there is no encoding, use "iso8859-1" -- Tcl_GetsObj() doesn't
* produce ByteArray objects.
*/
if (encoding == NULL) {
encoding = GetBinaryEncoding();
}
/*
* Object used by FilterInputBytes to keep track of how much data has been
* consumed from the channel buffers.
*/
gs.objPtr = objPtr;
gs.dstPtr = &dst;
gs.encoding = encoding;
gs.bufPtr = bufPtr;
gs.state = oldState;
gs.rawRead = 0;
gs.bytesWrote = 0;
gs.charsWrote = 0;
gs.totalChars = 0;
dst = objPtr->bytes + oldLength;
dstEnd = dst;
skip = 0;
eof = NULL;
inEofChar = statePtr->inEofChar;
ResetFlag(statePtr, CHANNEL_BLOCKED);
while (1) {
if (dst >= dstEnd) {
if (FilterInputBytes(chanPtr, &gs) != 0) {
goto restore;
}
dstEnd = dst + gs.bytesWrote;
}
/*
* Remember if EOF char is seen, then look for EOL anyhow, because the
* EOL might be before the EOF char.
*/
if (inEofChar != '\0') {
for (eol = dst; eol < dstEnd; eol++) {
if (*eol == inEofChar) {
dstEnd = eol;
eof = eol;
break;
}
}
}
/*
* On EOL, leave current file position pointing after the EOL, but
* don't store the EOL in the output string.
*/
switch (statePtr->inputTranslation) {
case TCL_TRANSLATE_LF:
for (eol = dst; eol < dstEnd; eol++) {
if (*eol == '\n') {
skip = 1;
goto gotEOL;
}
}
break;
case TCL_TRANSLATE_CR:
for (eol = dst; eol < dstEnd; eol++) {
if (*eol == '\r') {
skip = 1;
goto gotEOL;
}
}
break;
case TCL_TRANSLATE_CRLF:
for (eol = dst; eol < dstEnd; eol++) {
if (*eol == '\r') {
eol++;
/*
* If a CR is at the end of the buffer, then check for a
* LF at the begining of the next buffer, unless EOF char
* was found already.
*/
if (eol >= dstEnd) {
int offset;
if (eol != eof) {
offset = eol - objPtr->bytes;
dst = dstEnd;
if (FilterInputBytes(chanPtr, &gs) != 0) {
goto restore;
}
dstEnd = dst + gs.bytesWrote;
eol = objPtr->bytes + offset;
}
if (eol >= dstEnd) {
skip = 0;
goto gotEOL;
}
}
if (*eol == '\n') {
eol--;
skip = 2;
goto gotEOL;
}
}
}
break;
case TCL_TRANSLATE_AUTO:
eol = dst;
skip = 1;
if (GotFlag(statePtr, INPUT_SAW_CR)) {
ResetFlag(statePtr, INPUT_SAW_CR);
if ((eol < dstEnd) && (*eol == '\n')) {
/*
* Skip the raw bytes that make up the '\n'.
*/
int rawRead;
char tmp[TCL_UTF_MAX];
bufPtr = gs.bufPtr;
Tcl_ExternalToUtf(NULL, gs.encoding, RemovePoint(bufPtr),
gs.rawRead, statePtr->inputEncodingFlags
| TCL_ENCODING_NO_TERMINATE, &gs.state, tmp,
sizeof(tmp), &rawRead, NULL, NULL);
bufPtr->nextRemoved += rawRead;
gs.rawRead -= rawRead;
gs.bytesWrote--;
gs.charsWrote--;
memmove(dst, dst + 1, dstEnd - dst);
dstEnd--;
}
}
for (eol = dst; eol < dstEnd; eol++) {
if (*eol == '\r') {
eol++;
if (eol == dstEnd) {
/*
* If buffer ended on \r, peek ahead to see if a \n is
* available, unless EOF char was found already.
*/
if (eol != eof) {
int offset;
offset = eol - objPtr->bytes;
dst = dstEnd;
PeekAhead(chanPtr, &dstEnd, &gs);
eol = objPtr->bytes + offset;
}
if (eol >= dstEnd) {
eol--;
SetFlag(statePtr, INPUT_SAW_CR);
goto gotEOL;
}
}
if (*eol == '\n') {
skip++;
}
eol--;
goto gotEOL;
} else if (*eol == '\n') {
goto gotEOL;
}
}
}
if (eof != NULL) {
/*
* EOF character was seen. On EOF, leave current file position
* pointing at the EOF character, but don't store the EOF
* character in the output string.
*/
dstEnd = eof;
SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF);
statePtr->inputEncodingFlags |= TCL_ENCODING_END;
ResetFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR);
}
if (GotFlag(statePtr, CHANNEL_EOF)) {
skip = 0;
eol = dstEnd;
if (eol == objPtr->bytes + oldLength) {
/*
* If we didn't append any bytes before encountering EOF,
* caller needs to see -1.
*/
Tcl_SetObjLength(objPtr, oldLength);
CommonGetsCleanup(chanPtr);
copiedTotal = -1;
ResetFlag(statePtr, CHANNEL_BLOCKED);
goto done;
}
goto gotEOL;
}
dst = dstEnd;
}
/*
* Found EOL or EOF, but the output buffer may now contain too many UTF-8
* characters. We need to know how many raw bytes correspond to the number
* of UTF-8 characters we want, plus how many raw bytes correspond to the
* character(s) making up EOL (if any), so we can remove the correct
* number of bytes from the channel buffer.
*/
gotEOL:
/*
* Regenerate the top channel, in case it was changed due to
* self-modifying reflected transforms.
*/
if (chanPtr != statePtr->topChanPtr) {
TclChannelRelease((Tcl_Channel)chanPtr);
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
}
bufPtr = gs.bufPtr;
if (bufPtr == NULL) {
Tcl_Panic("Tcl_GetsObj: gotEOL reached with bufPtr==NULL");
}
statePtr->inputEncodingState = gs.state;
Tcl_ExternalToUtf(NULL, gs.encoding, RemovePoint(bufPtr), gs.rawRead,
statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE,
&statePtr->inputEncodingState, dst,
eol - dst + skip + TCL_UTF_MAX - 1, &gs.rawRead, NULL,
&gs.charsWrote);
bufPtr->nextRemoved += gs.rawRead;
/*
* Recycle all the emptied buffers.
*/
Tcl_SetObjLength(objPtr, eol - objPtr->bytes);
CommonGetsCleanup(chanPtr);
ResetFlag(statePtr, CHANNEL_BLOCKED);
copiedTotal = gs.totalChars + gs.charsWrote - skip;
goto done;
/*
* Couldn't get a complete line. This only happens if we get a error
* reading from the channel or we are non-blocking and there wasn't an EOL
* or EOF in the data available.
*/
restore:
/*
* Regenerate the top channel, in case it was changed due to
* self-modifying reflected transforms.
*/
if (chanPtr != statePtr->topChanPtr) {
TclChannelRelease((Tcl_Channel)chanPtr);
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
}
bufPtr = statePtr->inQueueHead;
if (bufPtr != NULL) {
bufPtr->nextRemoved = oldRemoved;
bufPtr = bufPtr->nextPtr;
}
for ( ; bufPtr != NULL; bufPtr = bufPtr->nextPtr) {
bufPtr->nextRemoved = BUFFER_PADDING;
}
CommonGetsCleanup(chanPtr);
statePtr->inputEncodingState = oldState;
statePtr->inputEncodingFlags = oldFlags;
Tcl_SetObjLength(objPtr, oldLength);
/*
* We didn't get a complete line so we need to indicate to UpdateInterest
* that the gets blocked. It will wait for more data instead of firing a
* timer, avoiding a busy wait. This is where we are assuming that the
* next operation is a gets. No more file events will be delivered on this
* channel until new data arrives or some operation is performed on the
* channel (e.g. gets, read, fconfigure) that changes the blocking state.
* Note that this means a file event will not be delivered even though a
* read would be able to consume the buffered data.
*/
SetFlag(statePtr, CHANNEL_NEED_MORE_DATA);
copiedTotal = -1;
/*
* Update the notifier state so we don't block while there is still data
* in the buffers.
*/
done:
assert(!GotFlag(statePtr, CHANNEL_EOF)
|| GotFlag(statePtr, CHANNEL_STICKY_EOF)
|| Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0);
assert(!(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED)
== (CHANNEL_EOF|CHANNEL_BLOCKED)));
/*
* Regenerate the top channel, in case it was changed due to
* self-modifying reflected transforms.
*/
if (chanPtr != statePtr->topChanPtr) {
TclChannelRelease((Tcl_Channel)chanPtr);
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
}
UpdateInterest(chanPtr);
TclChannelRelease((Tcl_Channel)chanPtr);
return copiedTotal;
}
/*
*---------------------------------------------------------------------------
*
* TclGetsObjBinary --
*
* A variation of Tcl_GetsObj that works directly on the buffers until
* end-of-line or end-of-file has been seen. Bytes read from the input
* channel return as a ByteArray obj.
*
* WARNING! The notion of "binary" used here is different from notions
* of "binary" used in other places. In particular, this "binary" routine
* may be called when an -eofchar is set on the channel.
*
* Results:
* Number of characters accumulated in the object or -1 if error,
* blocked, or EOF. If -1, use Tcl_GetErrno() to retrieve the POSIX error
* code for the error or condition that occurred.
*
* Side effects:
* Consumes input from the channel.
*
* On reading EOF, leave channel pointing at EOF char. On reading EOL,
* leave channel pointing after EOL, but don't return EOL in dst buffer.
*
*---------------------------------------------------------------------------
*/
static int
TclGetsObjBinary(
Tcl_Channel chan, /* Channel from which to read. */
Tcl_Obj *objPtr) /* The line read will be appended to this
* object as UTF-8 characters. */
{
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
ChannelBuffer *bufPtr;
int inEofChar, skip, copiedTotal, oldLength, oldFlags, oldRemoved;
int rawLen, byteLen, eolChar;
unsigned char *dst, *dstEnd, *eol, *eof, *byteArray;
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
bufPtr = statePtr->inQueueHead;
/*
* Preserved so we can restore the channel's state in case we don't find a
* newline in the available input.
*/
byteArray = Tcl_GetByteArrayFromObj(objPtr, &byteLen);
oldFlags = statePtr->inputEncodingFlags;
oldRemoved = BUFFER_PADDING;
oldLength = byteLen;
if (bufPtr != NULL) {
oldRemoved = bufPtr->nextRemoved;
}
rawLen = 0;
skip = 0;
eof = NULL;
inEofChar = statePtr->inEofChar;
/*
* Only handle TCL_TRANSLATE_LF and TCL_TRANSLATE_CR.
*/
eolChar = (statePtr->inputTranslation == TCL_TRANSLATE_LF) ? '\n' : '\r';
ResetFlag(statePtr, CHANNEL_BLOCKED);
while (1) {
/*
* Subtract the number of bytes that were removed from channel buffer
* during last call.
*/
if (bufPtr != NULL) {
bufPtr->nextRemoved += rawLen;
if (!IsBufferReady(bufPtr)) {
bufPtr = bufPtr->nextPtr;
}
}
if ((bufPtr == NULL) || (bufPtr->nextAdded == BUFFER_PADDING)) {
/*
* All channel buffers were exhausted and the caller still hasn't
* seen EOL. Need to read more bytes from the channel device. Side
* effect is to allocate another channel buffer.
*/
if (GetInput(chanPtr) != 0) {
goto restore;
}
bufPtr = statePtr->inQueueTail;
if (bufPtr == NULL) {
goto restore;
}
} else {
/*
* Incoming CHANNEL_STICKY_EOF is filtered out on entry. A new
* CHANNEL_STICKY_EOF set in this routine leads to return before
* coming back here. When we are not dealing with
* CHANNEL_STICKY_EOF, a CHANNEL_EOF implies an empty buffer.
* Here the buffer is non-empty so we know we're a non-EOF.
*/
assert(!GotFlag(statePtr, CHANNEL_STICKY_EOF));
assert(!GotFlag(statePtr, CHANNEL_EOF));
}
dst = (unsigned char *) RemovePoint(bufPtr);
dstEnd = dst + BytesLeft(bufPtr);
/*
* Remember if EOF char is seen, then look for EOL anyhow, because the
* EOL might be before the EOF char.
* XXX - in the binary case, consider coincident search for eol/eof.
*/
if (inEofChar != '\0') {
for (eol = dst; eol < dstEnd; eol++) {
if (*eol == inEofChar) {
dstEnd = eol;
eof = eol;
break;
}
}
}
/*
* On EOL, leave current file position pointing after the EOL, but
* don't store the EOL in the output string.
*/
for (eol = dst; eol < dstEnd; eol++) {
if (*eol == eolChar) {
skip = 1;
goto gotEOL;
}
}
if (eof != NULL) {
/*
* EOF character was seen. On EOF, leave current file position
* pointing at the EOF character, but don't store the EOF
* character in the output string.
*/
SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF);
statePtr->inputEncodingFlags |= TCL_ENCODING_END;
ResetFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR);
}
if (GotFlag(statePtr, CHANNEL_EOF)) {
skip = 0;
eol = dstEnd;
if ((dst == dstEnd) && (byteLen == oldLength)) {
/*
* If we didn't append any bytes before encountering EOF,
* caller needs to see -1.
*/
byteArray = Tcl_SetByteArrayLength(objPtr, oldLength);
CommonGetsCleanup(chanPtr);
copiedTotal = -1;
ResetFlag(statePtr, CHANNEL_BLOCKED);
goto done;
}
goto gotEOL;
}
if (GotFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_NONBLOCKING)
== (CHANNEL_BLOCKED|CHANNEL_NONBLOCKING)) {
goto restore;
}
/*
* Copy bytes from the channel buffer to the ByteArray. This may
* realloc space, so keep track of result.
*/
rawLen = dstEnd - dst;
byteArray = Tcl_SetByteArrayLength(objPtr, byteLen + rawLen);
memcpy(byteArray + byteLen, dst, rawLen);
byteLen += rawLen;
}
/*
* Found EOL or EOF, but the output buffer may now contain too many bytes.
* We need to know how many bytes correspond to the number we want, so we
* can remove the correct number of bytes from the channel buffer.
*/
gotEOL:
if (bufPtr == NULL) {
Tcl_Panic("TclGetsObjBinary: gotEOL reached with bufPtr==NULL");
}
rawLen = eol - dst;
byteArray = Tcl_SetByteArrayLength(objPtr, byteLen + rawLen);
memcpy(byteArray + byteLen, dst, rawLen);
byteLen += rawLen;
bufPtr->nextRemoved += rawLen + skip;
/*
* Convert the buffer if there was an encoding.
* XXX - unimplemented.
*/
if (statePtr->encoding != NULL) {
}
/*
* Recycle all the emptied buffers.
*/
CommonGetsCleanup(chanPtr);
ResetFlag(statePtr, CHANNEL_BLOCKED);
copiedTotal = byteLen;
goto done;
/*
* Couldn't get a complete line. This only happens if we get a error
* reading from the channel or we are non-blocking and there wasn't an EOL
* or EOF in the data available.
*/
restore:
bufPtr = statePtr->inQueueHead;
if (bufPtr) {
bufPtr->nextRemoved = oldRemoved;
bufPtr = bufPtr->nextPtr;
}
for ( ; bufPtr != NULL; bufPtr = bufPtr->nextPtr) {
bufPtr->nextRemoved = BUFFER_PADDING;
}
CommonGetsCleanup(chanPtr);
statePtr->inputEncodingFlags = oldFlags;
byteArray = Tcl_SetByteArrayLength(objPtr, oldLength);
/*
* We didn't get a complete line so we need to indicate to UpdateInterest
* that the gets blocked. It will wait for more data instead of firing a
* timer, avoiding a busy wait. This is where we are assuming that the
* next operation is a gets. No more file events will be delivered on this
* channel until new data arrives or some operation is performed on the
* channel (e.g. gets, read, fconfigure) that changes the blocking state.
* Note that this means a file event will not be delivered even though a
* read would be able to consume the buffered data.
*/
SetFlag(statePtr, CHANNEL_NEED_MORE_DATA);
copiedTotal = -1;
/*
* Update the notifier state so we don't block while there is still data
* in the buffers.
*/
done:
assert(!GotFlag(statePtr, CHANNEL_EOF)
|| GotFlag(statePtr, CHANNEL_STICKY_EOF)
|| Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0);
assert(!(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED)
== (CHANNEL_EOF|CHANNEL_BLOCKED)));
UpdateInterest(chanPtr);
TclChannelRelease((Tcl_Channel)chanPtr);
return copiedTotal;
}
/*
*---------------------------------------------------------------------------
*
* FreeBinaryEncoding --
*
* Frees any "iso8859-1" Tcl_Encoding created by [gets] on a binary
* channel in a thread as part of that thread's finalization.
*
* Results:
* None.
*
*---------------------------------------------------------------------------
*/
static void
FreeBinaryEncoding(
ClientData dummy) /* Not used */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
(void)dummy;
if (tsdPtr->binaryEncoding != NULL) {
Tcl_FreeEncoding(tsdPtr->binaryEncoding);
tsdPtr->binaryEncoding = NULL;
}
}
static Tcl_Encoding
GetBinaryEncoding()
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (tsdPtr->binaryEncoding == NULL) {
tsdPtr->binaryEncoding = Tcl_GetEncoding(NULL, "iso8859-1");
Tcl_CreateThreadExitHandler(FreeBinaryEncoding, NULL);
}
if (tsdPtr->binaryEncoding == NULL) {
Tcl_Panic("binary encoding is not available");
}
return tsdPtr->binaryEncoding;
}
/*
*---------------------------------------------------------------------------
*
* FilterInputBytes --
*
* Helper function for Tcl_GetsObj. Produces UTF-8 characters from raw
* bytes read from the channel.
*
* Consumes available bytes from channel buffers. When channel buffers
* are exhausted, reads more bytes from channel device into a new channel
* buffer. It is the caller's responsibility to free the channel buffers
* that have been exhausted.
*
* Results:
* The return value is -1 if there was an error reading from the channel,
* 0 otherwise.
*
* Side effects:
* Status object keeps track of how much data from channel buffers has
* been consumed and where UTF-8 bytes should be stored.
*
*---------------------------------------------------------------------------
*/
static int
FilterInputBytes(
Channel *chanPtr, /* Channel to read. */
GetsState *gsPtr) /* Current state of gets operation. */
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
ChannelBuffer *bufPtr;
char *raw, *dst;
int offset, toRead, dstNeeded, spaceLeft, result, rawLen;
Tcl_Obj *objPtr;
#define ENCODING_LINESIZE 20 /* Lower bound on how many bytes to convert at
* a time. Since we don't know a priori how
* many bytes of storage this many source
* bytes will use, we actually need at least
* ENCODING_LINESIZE * TCL_MAX_UTF bytes of
* room. */
objPtr = gsPtr->objPtr;
/*
* Subtract the number of bytes that were removed from channel buffer
* during last call.
*/
bufPtr = gsPtr->bufPtr;
if (bufPtr != NULL) {
bufPtr->nextRemoved += gsPtr->rawRead;
if (!IsBufferReady(bufPtr)) {
bufPtr = bufPtr->nextPtr;
}
}
gsPtr->totalChars += gsPtr->charsWrote;
if ((bufPtr == NULL) || (bufPtr->nextAdded == BUFFER_PADDING)) {
/*
* All channel buffers were exhausted and the caller still hasn't seen
* EOL. Need to read more bytes from the channel device. Side effect
* is to allocate another channel buffer.
*/
read:
if (GotFlag(statePtr, CHANNEL_NONBLOCKING|CHANNEL_BLOCKED)
== (CHANNEL_NONBLOCKING|CHANNEL_BLOCKED)) {
gsPtr->charsWrote = 0;
gsPtr->rawRead = 0;
return -1;
}
if (GetInput(chanPtr) != 0) {
gsPtr->charsWrote = 0;
gsPtr->rawRead = 0;
return -1;
}
bufPtr = statePtr->inQueueTail;
gsPtr->bufPtr = bufPtr;
if (bufPtr == NULL) {
gsPtr->charsWrote = 0;
gsPtr->rawRead = 0;
return -1;
}
} else {
/*
* Incoming CHANNEL_STICKY_EOF is filtered out on entry. A new
* CHANNEL_STICKY_EOF set in this routine leads to return before
* coming back here. When we are not dealing with CHANNEL_STICKY_EOF,
* a CHANNEL_EOF implies an empty buffer. Here the buffer is
* non-empty so we know we're a non-EOF.
*/
assert(!GotFlag(statePtr, CHANNEL_STICKY_EOF));
assert(!GotFlag(statePtr, CHANNEL_EOF));
}
/*
* Convert some of the bytes from the channel buffer to UTF-8. Space in
* objPtr's string rep is used to hold the UTF-8 characters. Grow the
* string rep if we need more space.
*/
raw = RemovePoint(bufPtr);
rawLen = BytesLeft(bufPtr);
dst = *gsPtr->dstPtr;
offset = dst - objPtr->bytes;
toRead = ENCODING_LINESIZE;
if (toRead > rawLen) {
toRead = rawLen;
}
dstNeeded = toRead * TCL_UTF_MAX;
spaceLeft = objPtr->length - offset;
if (dstNeeded > spaceLeft) {
int length = offset + ((offset < dstNeeded) ? dstNeeded : offset);
if (Tcl_AttemptSetObjLength(objPtr, length) == 0) {
length = offset + dstNeeded;
if (Tcl_AttemptSetObjLength(objPtr, length) == 0) {
dstNeeded = TCL_UTF_MAX - 1 + toRead;
length = offset + dstNeeded;
Tcl_SetObjLength(objPtr, length);
}
}
spaceLeft = length - offset;
dst = objPtr->bytes + offset;
*gsPtr->dstPtr = dst;
}
gsPtr->state = statePtr->inputEncodingState;
result = Tcl_ExternalToUtf(NULL, gsPtr->encoding, raw, rawLen,
statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE,
&statePtr->inputEncodingState, dst, spaceLeft, &gsPtr->rawRead,
&gsPtr->bytesWrote, &gsPtr->charsWrote);
/*
* Make sure that if we go through 'gets', that we reset the
* TCL_ENCODING_START flag still. [Bug #523988]
*/
statePtr->inputEncodingFlags &= ~TCL_ENCODING_START;
if (result == TCL_CONVERT_MULTIBYTE) {
/*
* The last few bytes in this channel buffer were the start of a
* multibyte sequence. If this buffer was full, then move them to the
* next buffer so the bytes will be contiguous.
*/
ChannelBuffer *nextPtr;
int extra;
nextPtr = bufPtr->nextPtr;
if (!IsBufferFull(bufPtr)) {
if (gsPtr->rawRead > 0) {
/*
* Some raw bytes were converted to UTF-8. Fall through,
* returning those UTF-8 characters because a EOL might be
* present in them.
*/
} else if (GotFlag(statePtr, CHANNEL_EOF)) {
/*
* There was a partial character followed by EOF on the
* device. Fall through, returning that nothing was found.
*/
bufPtr->nextRemoved = bufPtr->nextAdded;
} else {
/*
* There are no more cached raw bytes left. See if we can get
* some more, but avoid blocking on a non-blocking channel.
*/
goto read;
}
} else {
if (nextPtr == NULL) {
nextPtr = AllocChannelBuffer(statePtr->bufSize);
bufPtr->nextPtr = nextPtr;
statePtr->inQueueTail = nextPtr;
}
extra = rawLen - gsPtr->rawRead;
memcpy(nextPtr->buf + (BUFFER_PADDING - extra),
raw + gsPtr->rawRead, (size_t) extra);
nextPtr->nextRemoved -= extra;
bufPtr->nextAdded -= extra;
}
}
gsPtr->bufPtr = bufPtr;
return 0;
}
/*
*---------------------------------------------------------------------------
*
* PeekAhead --
*
* Helper function used by Tcl_GetsObj(). Called when we've seen a \r at
* the end of the UTF-8 string and want to look ahead one character to
* see if it is a \n.
*
* Results:
* *gsPtr->dstPtr is filled with a pointer to the start of the range of
* UTF-8 characters that were found by peeking and *dstEndPtr is filled
* with a pointer to the bytes just after the end of the range.
*
* Side effects:
* If no more raw bytes were available in one of the channel buffers,
* tries to perform a non-blocking read to get more bytes from the
* channel device.
*
*---------------------------------------------------------------------------
*/
static void
PeekAhead(
Channel *chanPtr, /* The channel to read. */
char **dstEndPtr, /* Filled with pointer to end of new range of
* UTF-8 characters. */
GetsState *gsPtr) /* Current state of gets operation. */
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
ChannelBuffer *bufPtr;
Tcl_DriverBlockModeProc *blockModeProc;
int bytesLeft;
bufPtr = gsPtr->bufPtr;
/*
* If there's any more raw input that's still buffered, we'll peek into
* that. Otherwise, only get more data from the channel driver if it looks
* like there might actually be more data. The assumption is that if the
* channel buffer is filled right up to the end, then there might be more
* data to read.
*/
blockModeProc = NULL;
if (bufPtr->nextPtr == NULL) {
bytesLeft = BytesLeft(bufPtr) - gsPtr->rawRead;
if (bytesLeft == 0) {
if (!IsBufferFull(bufPtr)) {
/*
* Don't peek ahead if last read was short read.
*/
goto cleanup;
}
if (!GotFlag(statePtr, CHANNEL_NONBLOCKING)) {
blockModeProc = Tcl_ChannelBlockModeProc(chanPtr->typePtr);
if (blockModeProc == NULL) {
/*
* Don't peek ahead if cannot set non-blocking mode.
*/
goto cleanup;
}
StackSetBlockMode(chanPtr, TCL_MODE_NONBLOCKING);
}
}
}
if (FilterInputBytes(chanPtr, gsPtr) == 0) {
*dstEndPtr = *gsPtr->dstPtr + gsPtr->bytesWrote;
}
if (blockModeProc != NULL) {
StackSetBlockMode(chanPtr, TCL_MODE_BLOCKING);
}
return;
cleanup:
bufPtr->nextRemoved += gsPtr->rawRead;
gsPtr->rawRead = 0;
gsPtr->totalChars += gsPtr->charsWrote;
gsPtr->bytesWrote = 0;
gsPtr->charsWrote = 0;
}
/*
*---------------------------------------------------------------------------
*
* CommonGetsCleanup --
*
* Helper function for Tcl_GetsObj() to restore the channel after a
* "gets" operation.
*
* Results:
* None.
*
* Side effects:
* Encoding may be freed.
*
*---------------------------------------------------------------------------
*/
static void
CommonGetsCleanup(
Channel *chanPtr)
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
ChannelBuffer *bufPtr, *nextPtr;
bufPtr = statePtr->inQueueHead;
for ( ; bufPtr != NULL; bufPtr = nextPtr) {
nextPtr = bufPtr->nextPtr;
if (IsBufferReady(bufPtr)) {
break;
}
RecycleBuffer(statePtr, bufPtr, 0);
}
statePtr->inQueueHead = bufPtr;
if (bufPtr == NULL) {
statePtr->inQueueTail = NULL;
} else {
/*
* If any multi-byte characters were split across channel buffer
* boundaries, the split-up bytes were moved to the next channel
* buffer by FilterInputBytes(). Move the bytes back to their original
* buffer because the caller could change the channel's encoding which
* could change the interpretation of whether those bytes really made
* up multi-byte characters after all.
*/
nextPtr = bufPtr->nextPtr;
for ( ; nextPtr != NULL; nextPtr = bufPtr->nextPtr) {
int extra;
extra = SpaceLeft(bufPtr);
if (extra > 0) {
memcpy(InsertPoint(bufPtr),
nextPtr->buf + (BUFFER_PADDING - extra),
(size_t) extra);
bufPtr->nextAdded += extra;
nextPtr->nextRemoved = BUFFER_PADDING;
}
bufPtr = nextPtr;
}
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_Read --
*
* Reads a given number of bytes from a channel. EOL and EOF translation
* is done on the bytes being read, so the number of bytes consumed from
* the channel may not be equal to the number of bytes stored in the
* destination buffer.
*
* No encoding conversions are applied to the bytes being read.
*
* Results:
* The number of bytes read, or -1 on error. Use Tcl_GetErrno() to
* retrieve the error code for the error that occurred.
*
* Side effects:
* May cause input to be buffered.
*
*----------------------------------------------------------------------
*/
int
Tcl_Read(
Tcl_Channel chan, /* The channel from which to read. */
char *dst, /* Where to store input read. */
int bytesToRead) /* Maximum number of bytes to read. */
{
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
if (CheckChannelErrors(statePtr, TCL_READABLE) != 0) {
return -1;
}
return DoRead(chanPtr, dst, bytesToRead, 0);
}
/*
*----------------------------------------------------------------------
*
* Tcl_ReadRaw --
*
* Reads a given number of bytes from a channel. EOL and EOF translation
* is done on the bytes being read, so the number of bytes consumed from
* the channel may not be equal to the number of bytes stored in the
* destination buffer.
*
* No encoding conversions are applied to the bytes being read.
*
* Results:
* The number of bytes read, or -1 on error. Use Tcl_GetErrno() to
* retrieve the error code for the error that occurred.
*
* Side effects:
* May cause input to be buffered.
*
*----------------------------------------------------------------------
*/
int
Tcl_ReadRaw(
Tcl_Channel chan, /* The channel from which to read. */
char *readBuf, /* Where to store input read. */
int bytesToRead) /* Maximum number of bytes to read. */
{
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
int copied = 0;
assert(bytesToRead > 0);
if (CheckChannelErrors(statePtr, TCL_READABLE | CHANNEL_RAW_MODE) != 0) {
return -1;
}
/*
* First read bytes from the push-back buffers.
*/
while (chanPtr->inQueueHead && bytesToRead > 0) {
ChannelBuffer *bufPtr = chanPtr->inQueueHead;
int bytesInBuffer = BytesLeft(bufPtr);
int toCopy = (bytesInBuffer < bytesToRead) ? bytesInBuffer
: bytesToRead;
/*
* Copy the current chunk into the read buffer.
*/
memcpy(readBuf, RemovePoint(bufPtr), toCopy);
bufPtr->nextRemoved += toCopy;
copied += toCopy;
readBuf += toCopy;
bytesToRead -= toCopy;
/*
* If the current buffer is empty recycle it.
*/
if (IsBufferEmpty(bufPtr)) {
chanPtr->inQueueHead = bufPtr->nextPtr;
if (chanPtr->inQueueHead == NULL) {
chanPtr->inQueueTail = NULL;
}
RecycleBuffer(chanPtr->state, bufPtr, 0);
}
}
/*
* Go to the driver only if we got nothing from pushback. Have to do it
* this way to avoid EOF mis-timings when we consider the ability that EOF
* may not be a permanent condition in the driver, and in that case we
* have to synchronize.
*/
if (copied) {
return copied;
}
/*
* This test not needed.
*/
if (bytesToRead > 0) {
int nread = ChanRead(chanPtr, readBuf, bytesToRead);
if (nread > 0) {
/*
* Successful read (short is OK) - add to bytes copied.
*/
copied += nread;
} else if (nread < 0) {
/*
* An error signaled. If CHANNEL_BLOCKED, then the error is not
* real, but an indication of blocked state. In that case, retain
* the flag and let caller receive the short read of copied bytes
* from the pushback. HOWEVER, if copied==0 bytes from pushback
* then repeat signalling the blocked state as an error to caller
* so there is no false report of an EOF. When !CHANNEL_BLOCKED,
* the error is real and passes on to caller.
*/
if (!GotFlag(statePtr, CHANNEL_BLOCKED) || copied == 0) {
copied = -1;
}
} else {
/*
* nread == 0. Driver is at EOF. Let that state filter up.
*/
}
}
return copied;
}
/*
*---------------------------------------------------------------------------
*
* Tcl_ReadChars --
*
* Reads from the channel until the requested number of characters have
* been seen, EOF is seen, or the channel would block. EOL and EOF
* translation is done. If reading binary data, the raw bytes are wrapped
* in a Tcl byte array object. Otherwise, the raw bytes are converted to
* UTF-8 using the channel's current encoding and stored in a Tcl string
* object.
*
* Results:
* The number of characters read, or -1 on error. Use Tcl_GetErrno() to
* retrieve the error code for the error that occurred.
*
* Side effects:
* May cause input to be buffered.
*
*---------------------------------------------------------------------------
*/
int
Tcl_ReadChars(
Tcl_Channel chan, /* The channel to read. */
Tcl_Obj *objPtr, /* Input data is stored in this object. */
int toRead, /* Maximum number of characters to store, or
* -1 to read all available data (up to EOF or
* when channel blocks). */
int appendFlag) /* If non-zero, data read from the channel
* will be appended to the object. Otherwise,
* the data will replace the existing contents
* of the object. */
{
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
if (CheckChannelErrors(statePtr, TCL_READABLE) != 0) {
/*
* Update the notifier state so we don't block while there is still
* data in the buffers.
*/
UpdateInterest(chanPtr);
return -1;
}
return DoReadChars(chanPtr, objPtr, toRead, appendFlag);
}
/*
*---------------------------------------------------------------------------
*
* DoReadChars --
*
* Reads from the channel until the requested number of characters have
* been seen, EOF is seen, or the channel would block. EOL and EOF
* translation is done. If reading binary data, the raw bytes are wrapped
* in a Tcl byte array object. Otherwise, the raw bytes are converted to
* UTF-8 using the channel's current encoding and stored in a Tcl string
* object.
*
* Results:
* The number of characters read, or -1 on error. Use Tcl_GetErrno() to
* retrieve the error code for the error that occurred.
*
* Side effects:
* May cause input to be buffered.
*
*---------------------------------------------------------------------------
*/
static int
DoReadChars(
Channel *chanPtr, /* The channel to read. */
Tcl_Obj *objPtr, /* Input data is stored in this object. */
int toRead, /* Maximum number of characters to store, or
* -1 to read all available data (up to EOF or
* when channel blocks). */
int appendFlag) /* If non-zero, data read from the channel
* will be appended to the object. Otherwise,
* the data will replace the existing contents
* of the object. */
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
ChannelBuffer *bufPtr;
int copied, copiedNow, result;
Tcl_Encoding encoding = statePtr->encoding;
int binaryMode;
#define UTF_EXPANSION_FACTOR 1024
int factor = UTF_EXPANSION_FACTOR;
binaryMode = (encoding == NULL)
&& (statePtr->inputTranslation == TCL_TRANSLATE_LF)
&& (statePtr->inEofChar == '\0');
if (appendFlag == 0) {
if (binaryMode) {
Tcl_SetByteArrayLength(objPtr, 0);
} else {
Tcl_SetObjLength(objPtr, 0);
/*
* We're going to access objPtr->bytes directly, so we must ensure
* that this is actually a string object (otherwise it might have
* been pure Unicode).
*
* Probably not needed anymore.
*/
TclGetString(objPtr);
}
}
/*
* Early out when next read will see eofchar.
*
* NOTE: See DoRead for argument that it's a bug (one we're keeping) to
* have this escape before the one for zero-char read request.
*/
if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) {
SetFlag(statePtr, CHANNEL_EOF);
assert(statePtr->inputEncodingFlags & TCL_ENCODING_END);
assert(!GotFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR));
/* TODO: We don't need this call? */
UpdateInterest(chanPtr);
return 0;
}
/*
* Special handling for zero-char read request.
*/
if (toRead == 0) {
if (GotFlag(statePtr, CHANNEL_EOF)) {
statePtr->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_EOF);
statePtr->inputEncodingFlags &= ~TCL_ENCODING_END;
/* TODO: We don't need this call? */
UpdateInterest(chanPtr);
return 0;
}
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
/*
* Must clear the BLOCKED|EOF flags here since we check before reading.
*/
if (GotFlag(statePtr, CHANNEL_EOF)) {
statePtr->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_EOF);
statePtr->inputEncodingFlags &= ~TCL_ENCODING_END;
for (copied = 0; (unsigned) toRead > 0; ) {
copiedNow = -1;
if (statePtr->inQueueHead != NULL) {
if (binaryMode) {
copiedNow = ReadBytes(statePtr, objPtr, toRead);
} else {
copiedNow = ReadChars(statePtr, objPtr, toRead, &factor);
}
/*
* If the current buffer is empty recycle it.
*/
bufPtr = statePtr->inQueueHead;
if (IsBufferEmpty(bufPtr)) {
ChannelBuffer *nextPtr = bufPtr->nextPtr;
RecycleBuffer(statePtr, bufPtr, 0);
statePtr->inQueueHead = nextPtr;
if (nextPtr == NULL) {
statePtr->inQueueTail = NULL;
}
}
}
if (copiedNow < 0) {
if (GotFlag(statePtr, CHANNEL_EOF)) {
break;
}
if (GotFlag(statePtr, CHANNEL_NONBLOCKING|CHANNEL_BLOCKED)
== (CHANNEL_NONBLOCKING|CHANNEL_BLOCKED)) {
break;
}
result = GetInput(chanPtr);
if (chanPtr != statePtr->topChanPtr) {
TclChannelRelease((Tcl_Channel)chanPtr);
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
}
if (result != 0) {
if (!GotFlag(statePtr, CHANNEL_BLOCKED)) {
copied = -1;
}
break;
}
} else {
copied += copiedNow;
toRead -= copiedNow;
}
}
/*
* Failure to fill a channel buffer may have left channel reporting a
* "blocked" state, but so long as we fulfilled the request here, the
* caller does not consider us blocked.
*/
if (toRead == 0) {
ResetFlag(statePtr, CHANNEL_BLOCKED);
}
/*
* Regenerate the top channel, in case it was changed due to
* self-modifying reflected transforms.
*/
if (chanPtr != statePtr->topChanPtr) {
TclChannelRelease((Tcl_Channel)chanPtr);
chanPtr = statePtr->topChanPtr;
TclChannelPreserve((Tcl_Channel)chanPtr);
}
/*
* Update the notifier state so we don't block while there is still data
* in the buffers.
*/
assert(!GotFlag(statePtr, CHANNEL_EOF)
|| GotFlag(statePtr, CHANNEL_STICKY_EOF)
|| Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0);
assert(!(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED)
== (CHANNEL_EOF|CHANNEL_BLOCKED)));
UpdateInterest(chanPtr);
TclChannelRelease((Tcl_Channel)chanPtr);
return copied;
}
/*
*---------------------------------------------------------------------------
*
* ReadBytes --
*
* Reads from the channel until the requested number of bytes have been
* seen, EOF is seen, or the channel would block. Bytes from the channel
* are stored in objPtr as a ByteArray object. EOL and EOF translation
* are done.
*
* 'bytesToRead' can safely be a very large number because space is only
* allocated to hold data read from the channel as needed.
*
* Results:
* The return value is the number of bytes appended to the object, or
* -1 to indicate that zero bytes were read due to an EOF.
*
* Side effects:
* The storage of bytes in objPtr can cause (re-)allocation of memory.
*
*---------------------------------------------------------------------------
*/
static int
ReadBytes(
ChannelState *statePtr, /* State of the channel to read. */
Tcl_Obj *objPtr, /* Input data is appended to this ByteArray
* object. Its length is how much space has
* been allocated to hold data, not how many
* bytes of data have been stored in the
* object. */
int bytesToRead) /* Maximum number of bytes to store, or < 0 to
* get all available bytes. Bytes are obtained
* from the first buffer in the queue - even
* if this number is larger than the number of
* bytes available in the first buffer, only
* the bytes from the first buffer are
* returned. */
{
ChannelBuffer *bufPtr = statePtr->inQueueHead;
int srcLen = BytesLeft(bufPtr);
int toRead = bytesToRead>srcLen || bytesToRead<0 ? srcLen : bytesToRead;
TclAppendBytesToByteArray(objPtr, (unsigned char *) RemovePoint(bufPtr),
toRead);
bufPtr->nextRemoved += toRead;
return toRead;
}
/*
*---------------------------------------------------------------------------
*
* ReadChars --
*
* Reads from the channel until the requested number of UTF-8 characters
* have been seen, EOF is seen, or the channel would block. Raw bytes
* from the channel are converted to UTF-8 and stored in objPtr. EOL and
* EOF translation is done.
*
* 'charsToRead' can safely be a very large number because space is only
* allocated to hold data read from the channel as needed.
*
* 'charsToRead' may *not* be 0.
*
* Results:
* The return value is the number of characters appended to the object,
* *offsetPtr is filled with the number of bytes that were appended, and
* *factorPtr is filled with the expansion factor used to guess how many
* bytes of UTF-8 to allocate to hold N source bytes.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------------
*/
static int
ReadChars(
ChannelState *statePtr, /* State of channel to read. */
Tcl_Obj *objPtr, /* Input data is appended to this object.
* objPtr->length is how much space has been
* allocated to hold data, not how many bytes
* of data have been stored in the object. */
int charsToRead, /* Maximum number of characters to store, or
* -1 to get all available characters.
* Characters are obtained from the first
* buffer in the queue -- even if this number
* is larger than the number of characters
* available in the first buffer, only the
* characters from the first buffer are
* returned. The execption is when there is
* not any complete character in the first
* buffer. In that case, a recursive call
* effectively obtains chars from the
* second buffer. */
int *factorPtr) /* On input, contains a guess of how many
* bytes need to be allocated to hold the
* result of converting N source bytes to
* UTF-8. On output, contains another guess
* based on the data seen so far. */
{
Tcl_Encoding encoding = statePtr->encoding? statePtr->encoding
: GetBinaryEncoding();
Tcl_EncodingState savedState = statePtr->inputEncodingState;
ChannelBuffer *bufPtr = statePtr->inQueueHead;
int savedIEFlags = statePtr->inputEncodingFlags;
int savedFlags = statePtr->flags;
char *dst, *src = RemovePoint(bufPtr);
int numBytes, srcLen = BytesLeft(bufPtr);
/*
* One src byte can yield at most one character. So when the number of
* src bytes we plan to read is less than the limit on character count to
* be read, clearly we will remain within that limit, and we can use the
* value of "srcLen" as a tighter limit for sizing receiving buffers.
*/
int toRead = ((charsToRead<0)||(charsToRead > srcLen)) ? srcLen : charsToRead;
/*
* 'factor' is how much we guess that the bytes in the source buffer will
* expand when converted to UTF-8 chars. This guess comes from analyzing
* how many characters were produced by the previous pass.
*/
int factor = *factorPtr;
int dstLimit = TCL_UTF_MAX - 1 + toRead * factor / UTF_EXPANSION_FACTOR;
(void) TclGetStringFromObj(objPtr, &numBytes);
Tcl_AppendToObj(objPtr, NULL, dstLimit);
if (toRead == srcLen) {
unsigned int size;
dst = TclGetStringStorage(objPtr, &size) + numBytes;
dstLimit = size - numBytes;
} else {
dst = TclGetString(objPtr) + numBytes;
}
/*
* This routine is burdened with satisfying several constraints. It cannot
* append more than 'charsToRead` chars onto objPtr. This is measured
* after encoding and translation transformations are completed. There is
* no precise number of src bytes that can be associated with the limit.
* Yet, when we are done, we must know precisely the number of src bytes
* that were consumed to produce the appended chars, so that all
* subsequent bytes are left in the buffers for future read operations.
*
* The consequence is that we have no choice but to implement a "trial and
* error" approach, where in general we may need to perform
* transformations and copies multiple times to achieve a consistent set
* of results. This takes the shape of a loop.
*/
while (1) {
int dstDecoded, dstRead, dstWrote, srcRead, numChars, code;
int flags = statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE;
if (charsToRead > 0) {
flags |= TCL_ENCODING_CHAR_LIMIT;
numChars = charsToRead;
}
/*
* Perform the encoding transformation. Read no more than srcLen
* bytes, write no more than dstLimit bytes.
*
* Some trickiness with encoding flags here. We do not want the end
* of a buffer to be treated as the end of all input when the presence
* of bytes in a next buffer are already known to exist. This is
* checked with an assert() because so far no test case causing the
* assertion to be false has been created. The normal operations of
* channel reading appear to cause EOF and TCL_ENCODING_END setting to
* appear only in situations where there are no further bytes in any
* buffers.
*/
assert(bufPtr->nextPtr == NULL || BytesLeft(bufPtr->nextPtr) == 0
|| (statePtr->inputEncodingFlags & TCL_ENCODING_END) == 0);
code = Tcl_ExternalToUtf(NULL, encoding, src, srcLen,
flags, &statePtr->inputEncodingState,
dst, dstLimit, &srcRead, &dstDecoded, &numChars);
/*
* Perform the translation transformation in place. Read no more than
* the dstDecoded bytes the encoding transformation actually produced.
* Capture the number of bytes written in dstWrote. Capture the number
* of bytes actually consumed in dstRead.
*/
dstWrote = dstLimit;
dstRead = dstDecoded;
TranslateInputEOL(statePtr, dst, dst, &dstWrote, &dstRead);
if (dstRead < dstDecoded) {
/*
* The encoding transformation produced bytes that the translation
* transformation did not consume. Why did this happen?
*/
if (statePtr->inEofChar && dst[dstRead] == statePtr->inEofChar) {
/*
* 1) There's an eof char set on the channel, and
* we saw it and stopped translating at that point.
*
* NOTE the bizarre spec of TranslateInputEOL in this case.
* Clearly the eof char had to be read in order to account for
* the stopping, but the value of dstRead does not include it.
*
* Also rather bizarre, our caller can only notice an EOF
* condition if we return the value -1 as the number of chars
* read. This forces us to perform a 2-call dance where the
* first call can read all the chars up to the eof char, and
* the second call is solely for consuming the encoded eof
* char then pointed at by src so that we can return that
* magic -1 value. This seems really wasteful, especially
* since the first decoding pass of each call is likely to
* decode many bytes beyond that eof char that's all we care
* about.
*/
if (dstRead == 0) {
/*
* Curious choice in the eof char handling. We leave the
* eof char in the buffer. So, no need to compute a proper
* srcRead value. At this point, there are no chars before
* the eof char in the buffer.
*/
Tcl_SetObjLength(objPtr, numBytes);
return -1;
}
{
/*
* There are chars leading the buffer before the eof char.
* Adjust the dstLimit so we go back and read only those
* and do not encounter the eof char this time.
*/
dstLimit = dstRead + (TCL_UTF_MAX - 1);
statePtr->flags = savedFlags;
statePtr->inputEncodingFlags = savedIEFlags;
statePtr->inputEncodingState = savedState;
continue;
}
}
/*
* 2) The other way to read fewer bytes than are decoded is when
* the final byte is \r and we're in a CRLF translation mode so
* we cannot decide whether to record \r or \n yet.
*/
assert(dst[dstRead] == '\r');
assert(statePtr->inputTranslation == TCL_TRANSLATE_CRLF);
if (dstWrote > 0) {
/*
* There are chars we can read before we hit the bare CR. Go
* back with a smaller dstLimit so we get them in the next
* pass, compute a matching srcRead, and don't end up back
* here in this call.
*/
dstLimit = dstRead + (TCL_UTF_MAX - 1);
statePtr->flags = savedFlags;
statePtr->inputEncodingFlags = savedIEFlags;
statePtr->inputEncodingState = savedState;
continue;
}
assert(dstWrote == 0);
assert(dstRead == 0);
/*
* We decoded only the bare CR, and we cannot read a translated
* char from that alone. We have to know what's next. So why do
* we only have the one decoded char?
*/
if (code != TCL_OK) {
int read, decoded, count;
char buffer[TCL_UTF_MAX + 1];
/*
* Didn't get everything the buffer could offer
*/
statePtr->flags = savedFlags;
statePtr->inputEncodingFlags = savedIEFlags;
statePtr->inputEncodingState = savedState;
assert(bufPtr->nextPtr == NULL
|| BytesLeft(bufPtr->nextPtr) == 0 || 0 ==
(statePtr->inputEncodingFlags & TCL_ENCODING_END));
Tcl_ExternalToUtf(NULL, encoding, src, srcLen,
(statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE),
&statePtr->inputEncodingState, buffer, sizeof(buffer),
&read, &decoded, &count);
if (count == 2) {
if (buffer[1] == '\n') {
/* \r\n translate to \n */
dst[0] = '\n';
bufPtr->nextRemoved += read;
} else {
dst[0] = '\r';
bufPtr->nextRemoved += srcRead;
}
statePtr->inputEncodingFlags &= ~TCL_ENCODING_START;
Tcl_SetObjLength(objPtr, numBytes + 1);
return 1;
}
} else if (statePtr->flags & CHANNEL_EOF) {
/*
* The bare \r is the only char and we will never read a
* subsequent char to make the determination.
*/
dst[0] = '\r';
bufPtr->nextRemoved = bufPtr->nextAdded;
Tcl_SetObjLength(objPtr, numBytes + 1);
return 1;
}
/*
* Revise the dstRead value so that the numChars calc below
* correctly computes zero characters read.
*/
dstRead = numChars;
/* FALL THROUGH - get more data (dstWrote == 0) */
}
/*
* The translation transformation can only reduce the number of chars
* when it converts \r\n into \n. The reduction in the number of chars
* is the difference in bytes read and written.
*/
numChars -= (dstRead - dstWrote);
if (charsToRead > 0 && numChars > charsToRead) {
/*
* TODO: This cannot happen anymore.
*
* We read more chars than allowed. Reset limits to prevent that
* and try again. Don't forget the extra padding of TCL_UTF_MAX
* bytes demanded by the Tcl_ExternalToUtf() call!
*/
dstLimit = Tcl_UtfAtIndex(dst, charsToRead) - dst + (TCL_UTF_MAX - 1);
statePtr->flags = savedFlags;
statePtr->inputEncodingFlags = savedIEFlags;
statePtr->inputEncodingState = savedState;
continue;
}
if (dstWrote == 0) {
ChannelBuffer *nextPtr;
/*
* We were not able to read any chars.
*/
assert(numChars == 0);
/*
* There is one situation where this is the correct final result.
* If the src buffer contains only a single \n byte, and we are in
* TCL_TRANSLATE_AUTO mode, and when the translation pass was made
* the INPUT_SAW_CR flag was set on the channel. In that case, the
* correct behavior is to consume that \n and produce the empty
* string.
*/
if (dstRead == 1 && dst[0] == '\n') {
assert(statePtr->inputTranslation == TCL_TRANSLATE_AUTO);
goto consume;
}
/*
* Otherwise, reading zero characters indicates there's something
* incomplete at the end of the src buffer. Maybe there were not
* enough src bytes to decode into a char. Maybe a lone \r could
* not be translated (crlf mode). Need to combine any unused src
* bytes we have in the first buffer with subsequent bytes to try
* again.
*/
nextPtr = bufPtr->nextPtr;
if (nextPtr == NULL) {
if (srcLen > 0) {
SetFlag(statePtr, CHANNEL_NEED_MORE_DATA);
}
Tcl_SetObjLength(objPtr, numBytes);
return -1;
}
/*
* Space is made at the beginning of the buffer to copy the
* previous unused bytes there. Check first if the buffer we are
* using actually has enough space at its beginning for the data
* we are copying. Because if not we will write over the buffer
* management information, especially the 'nextPtr'.
*
* Note that the BUFFER_PADDING (See AllocChannelBuffer) is used
* to prevent exactly this situation. I.e. it should never happen.
* Therefore it is ok to panic should it happen despite the
* precautions.
*/
if (nextPtr->nextRemoved - srcLen < 0) {
Tcl_Panic("Buffer Underflow, BUFFER_PADDING not enough");
}
nextPtr->nextRemoved -= srcLen;
memcpy(RemovePoint(nextPtr), src, srcLen);
RecycleBuffer(statePtr, bufPtr, 0);
statePtr->inQueueHead = nextPtr;
Tcl_SetObjLength(objPtr, numBytes);
return ReadChars(statePtr, objPtr, charsToRead, factorPtr);
}
statePtr->inputEncodingFlags &= ~TCL_ENCODING_START;
consume:
bufPtr->nextRemoved += srcRead;
/*
* If this read contained multibyte characters, revise factorPtr so
* the next read will allocate bigger buffers.
*/
if (numChars && numChars < srcRead) {
*factorPtr = srcRead * UTF_EXPANSION_FACTOR / numChars;
}
Tcl_SetObjLength(objPtr, numBytes + dstWrote);
return numChars;
}
}
/*
*---------------------------------------------------------------------------
*
* TranslateInputEOL --
*
* Perform input EOL and EOF translation on the source buffer, leaving
* the translated result in the destination buffer.
*
* Results:
* The return value is 1 if the EOF character was found when copying
* bytes to the destination buffer, 0 otherwise.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------------
*/
static void
TranslateInputEOL(
ChannelState *statePtr, /* Channel being read, for EOL translation and
* EOF character. */
char *dstStart, /* Output buffer filled with chars by applying
* appropriate EOL translation to source
* characters. */
const char *srcStart, /* Source characters. */
int *dstLenPtr, /* On entry, the maximum length of output
* buffer in bytes. On exit, the number of
* bytes actually used in output buffer. */
int *srcLenPtr) /* On entry, the length of source buffer. On
* exit, the number of bytes read from the
* source buffer. */
{
const char *eof = NULL;
int dstLen = *dstLenPtr;
int srcLen = *srcLenPtr;
int inEofChar = statePtr->inEofChar;
/*
* Depending on the translation mode in use, there's no need to scan more
* srcLen bytes at srcStart than can possibly transform to dstLen bytes.
* This keeps the scan for eof char below from being pointlessly long.
*/
switch (statePtr->inputTranslation) {
case TCL_TRANSLATE_LF:
case TCL_TRANSLATE_CR:
if (srcLen > dstLen) {
/*
* In these modes, each src byte become a dst byte.
*/
srcLen = dstLen;
}
break;
default:
/*
* In other modes, at most 2 src bytes become a dst byte.
*/
if (srcLen/2 > dstLen) {
srcLen = 2 * dstLen;
}
break;
}
if (inEofChar != '\0') {
/*
* Make sure we do not read past any logical end of channel input
* created by the presence of the input eof char.
*/
if ((eof = (const char *)memchr(srcStart, inEofChar, srcLen))) {
srcLen = eof - srcStart;
}
}
switch (statePtr->inputTranslation) {
case TCL_TRANSLATE_LF:
case TCL_TRANSLATE_CR:
if (dstStart != srcStart) {
memcpy(dstStart, srcStart, srcLen);
}
if (statePtr->inputTranslation == TCL_TRANSLATE_CR) {
char *dst = dstStart;
char *dstEnd = dstStart + srcLen;
while ((dst = (char *)memchr(dst, '\r', dstEnd - dst))) {
*dst++ = '\n';
}
}
dstLen = srcLen;
break;
case TCL_TRANSLATE_CRLF: {
const char *crFound, *src = srcStart;
char *dst = dstStart;
int lesser = (dstLen < srcLen) ? dstLen : srcLen;
while ((crFound = (const char *)memchr(src, '\r', lesser))) {
int numBytes = crFound - src;
memmove(dst, src, numBytes);
dst += numBytes; dstLen -= numBytes;
src += numBytes; srcLen -= numBytes;
if (srcLen == 1) {
/* valid src bytes end in \r */
if (eof) {
*dst++ = '\r';
src++; srcLen--;
} else {
lesser = 0;
break;
}
} else if (src[1] == '\n') {
*dst++ = '\n';
src += 2; srcLen -= 2;
} else {
*dst++ = '\r';
src++; srcLen--;
}
dstLen--;
lesser = (dstLen < srcLen) ? dstLen : srcLen;
}
memmove(dst, src, lesser);
srcLen = src + lesser - srcStart;
dstLen = dst + lesser - dstStart;
break;
}
case TCL_TRANSLATE_AUTO: {
const char *crFound, *src = srcStart;
char *dst = dstStart;
int lesser;
if ((statePtr->flags & INPUT_SAW_CR) && srcLen) {
if (*src == '\n') { src++; srcLen--; }
ResetFlag(statePtr, INPUT_SAW_CR);
}
lesser = (dstLen < srcLen) ? dstLen : srcLen;
while ((crFound = (const char *)memchr(src, '\r', lesser))) {
int numBytes = crFound - src;
memmove(dst, src, numBytes);
dst[numBytes] = '\n';
dst += numBytes + 1; dstLen -= numBytes + 1;
src += numBytes + 1; srcLen -= numBytes + 1;
if (srcLen == 0) {
SetFlag(statePtr, INPUT_SAW_CR);
} else if (*src == '\n') {
src++; srcLen--;
}
lesser = (dstLen < srcLen) ? dstLen : srcLen;
}
memmove(dst, src, lesser);
srcLen = src + lesser - srcStart;
dstLen = dst + lesser - dstStart;
break;
}
default:
Tcl_Panic("unknown input translation %d", statePtr->inputTranslation);
}
*dstLenPtr = dstLen;
*srcLenPtr = srcLen;
if (srcStart + srcLen == eof) {
/*
* EOF character was seen in EOL translated range. Leave current file
* position pointing at the EOF character, but don't store the EOF
* character in the output string.
*/
SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF);
statePtr->inputEncodingFlags |= TCL_ENCODING_END;
ResetFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR);
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_Ungets --
*
* Causes the supplied string to be added to the input queue of the
* channel, at either the head or tail of the queue.
*
* Results:
* The number of bytes stored in the channel, or -1 on error.
*
* Side effects:
* Adds input to the input queue of a channel.
*
*----------------------------------------------------------------------
*/
int
Tcl_Ungets(
Tcl_Channel chan, /* The channel for which to add the input. */
const char *str, /* The input itself. */
int len, /* The length of the input. */
int atEnd) /* If non-zero, add at end of queue; otherwise
* add at head of queue. */
{
Channel *chanPtr; /* The real IO channel. */
ChannelState *statePtr; /* State of actual channel. */
ChannelBuffer *bufPtr; /* Buffer to contain the data. */
int flags;
chanPtr = (Channel *) chan;
statePtr = chanPtr->state;
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
/*
* CheckChannelErrors clears too many flag bits in this one case.
*/
flags = statePtr->flags;
if (CheckChannelErrors(statePtr, TCL_READABLE) != 0) {
len = -1;
goto done;
}
statePtr->flags = flags;
/*
* Clear the EOF flags, and clear the BLOCKED bit.
*/
if (GotFlag(statePtr, CHANNEL_EOF)) {
statePtr->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(statePtr,
CHANNEL_BLOCKED | CHANNEL_STICKY_EOF | CHANNEL_EOF | INPUT_SAW_CR);
statePtr->inputEncodingFlags &= ~TCL_ENCODING_END;
bufPtr = AllocChannelBuffer(len);
memcpy(InsertPoint(bufPtr), str, len);
bufPtr->nextAdded += len;
if (statePtr->inQueueHead == NULL) {
bufPtr->nextPtr = NULL;
statePtr->inQueueHead = bufPtr;
statePtr->inQueueTail = bufPtr;
} else if (atEnd) {
bufPtr->nextPtr = NULL;
statePtr->inQueueTail->nextPtr = bufPtr;
statePtr->inQueueTail = bufPtr;
} else {
bufPtr->nextPtr = statePtr->inQueueHead;
statePtr->inQueueHead = bufPtr;
}
/*
* Update the notifier state so we don't block while there is still data
* in the buffers.
*/
done:
UpdateInterest(chanPtr);
return len;
}
/*
*----------------------------------------------------------------------
*
* Tcl_Flush --
*
* Flushes output data on a channel.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* May flush output queued on this channel.
*
*----------------------------------------------------------------------
*/
int
Tcl_Flush(
Tcl_Channel chan) /* The Channel to flush. */
{
int result; /* Of calling FlushChannel. */
Channel *chanPtr = (Channel *) chan;
/* The actual channel. */
ChannelState *statePtr = chanPtr->state;
/* State of actual channel. */
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
if (CheckChannelErrors(statePtr, TCL_WRITABLE) != 0) {
return TCL_ERROR;
}
result = FlushChannel(NULL, chanPtr, 0);
if (result != 0) {
return TCL_ERROR;
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* DiscardInputQueued --
*
* Discards any input read from the channel but not yet consumed by Tcl
* reading commands.
*
* Results:
* None.
*
* Side effects:
* May discard input from the channel. If discardLastBuffer is zero,
* leaves one buffer in place for back-filling.
*
*----------------------------------------------------------------------
*/
static void
DiscardInputQueued(
ChannelState *statePtr, /* Channel on which to discard the queued
* input. */
int discardSavedBuffers) /* If non-zero, discard all buffers including
* last one. */
{
ChannelBuffer *bufPtr, *nxtPtr;
/* Loop variables. */
bufPtr = statePtr->inQueueHead;
statePtr->inQueueHead = NULL;
statePtr->inQueueTail = NULL;
for (; bufPtr != NULL; bufPtr = nxtPtr) {
nxtPtr = bufPtr->nextPtr;
RecycleBuffer(statePtr, bufPtr, discardSavedBuffers);
}
/*
* If discardSavedBuffers is nonzero, must also discard any previously
* saved buffer in the saveInBufPtr field.
*/
if (discardSavedBuffers && statePtr->saveInBufPtr != NULL) {
ReleaseChannelBuffer(statePtr->saveInBufPtr);
statePtr->saveInBufPtr = NULL;
}
}
/*
*---------------------------------------------------------------------------
*
* GetInput --
*
* Reads input data from a device into a channel buffer.
*
* IMPORTANT! This routine is only called on a chanPtr argument
* that is the top channel of a stack!
*
* Results:
* The return value is the Posix error code if an error occurred while
* reading from the file, or 0 otherwise.
*
* Side effects:
* Reads from the underlying device.
*
*---------------------------------------------------------------------------
*/
static int
GetInput(
Channel *chanPtr) /* Channel to read input from. */
{
int toRead; /* How much to read? */
int result; /* Of calling driver. */
int nread; /* How much was read from channel? */
ChannelBuffer *bufPtr; /* New buffer to add to input queue. */
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
/*
* Verify that all callers know better than to call us when
* it's recorded that the next char waiting to be read is the
* eofchar.
*/
assert(!GotFlag(statePtr, CHANNEL_STICKY_EOF));
/*
* Prevent reading from a dead channel -- a channel that has been closed
* but not yet deallocated, which can happen if the exit handler for
* channel cleanup has run but the channel is still registered in some
* interpreter.
*/
if (CheckForDeadChannel(NULL, statePtr)) {
return EINVAL;
}
/*
* WARNING: There was once a comment here claiming that it was
* a bad idea to make another call to the inputproc of a channel
* driver when EOF has already been detected on the channel. Through
* much of Tcl's history, this warning was then completely negated
* by having all (most?) read paths clear the EOF setting before
* reaching here. So we had a guard that was never triggered.
*
* Don't be tempted to restore the guard. Even if EOF is set on
* the channel, continue through and call the inputproc again. This
* is the way to enable the ability to [read] again beyond the EOF,
* which seems a strange thing to do, but for which use cases exist
* [Tcl Bug 5adc350683] and which may even be essential for channels
* representing things like ttys or other devices where the stream
* might take the logical form of a series of 'files' separated by
* an EOF condition.
*/
/*
* First check for more buffers in the pushback area of the topmost
* channel in the stack and use them. They can be the result of a
* transformation which went away without reading all the information
* placed in the area when it was stacked.
*/
if (chanPtr->inQueueHead != NULL) {
/* TODO: Tests to cover this. */
assert(statePtr->inQueueHead == NULL);
statePtr->inQueueHead = chanPtr->inQueueHead;
statePtr->inQueueTail = chanPtr->inQueueTail;
chanPtr->inQueueHead = NULL;
chanPtr->inQueueTail = NULL;
return 0;
}
/*
* Nothing in the pushback area, fall back to the usual handling (driver,
* etc.)
*/
/*
* See if we can fill an existing buffer. If we can, read only as much as
* will fit in it. Otherwise allocate a new buffer, add it to the input
* queue and attempt to fill it to the max.
*/
bufPtr = statePtr->inQueueTail;
if ((bufPtr == NULL) || IsBufferFull(bufPtr)) {
bufPtr = statePtr->saveInBufPtr;
statePtr->saveInBufPtr = NULL;
/*
* Check the actual buffersize against the requested buffersize.
* Saved buffers of the wrong size are squashed. This is done to honor
* dynamic changes of the buffersize made by the user.
*
* TODO: Tests to cover this.
*/
if ((bufPtr != NULL)
&& (bufPtr->bufLength - BUFFER_PADDING != statePtr->bufSize)) {
ReleaseChannelBuffer(bufPtr);
bufPtr = NULL;
}
if (bufPtr == NULL) {
bufPtr = AllocChannelBuffer(statePtr->bufSize);
}
bufPtr->nextPtr = NULL;
toRead = SpaceLeft(bufPtr);
assert(toRead == statePtr->bufSize);
if (statePtr->inQueueTail == NULL) {
statePtr->inQueueHead = bufPtr;
} else {
statePtr->inQueueTail->nextPtr = bufPtr;
}
statePtr->inQueueTail = bufPtr;
} else {
toRead = SpaceLeft(bufPtr);
}
PreserveChannelBuffer(bufPtr);
nread = ChanRead(chanPtr, InsertPoint(bufPtr), toRead);
if (nread < 0) {
result = Tcl_GetErrno();
} else {
result = 0;
bufPtr->nextAdded += nread;
}
ReleaseChannelBuffer(bufPtr);
return result;
}
/*
*----------------------------------------------------------------------
*
* Tcl_Seek --
*
* Implements seeking on Tcl Channels. This is a public function so that
* other C facilities may be implemented on top of it.
*
* Results:
* The new access point or -1 on error. If error, use Tcl_GetErrno() to
* retrieve the POSIX error code for the error that occurred.
*
* Side effects:
* May flush output on the channel. May discard queued input.
*
*----------------------------------------------------------------------
*/
Tcl_WideInt
Tcl_Seek(
Tcl_Channel chan, /* The channel on which to seek. */
Tcl_WideInt offset, /* Offset to seek to. */
int mode) /* Relative to which location to seek? */
{
Channel *chanPtr = (Channel *) chan;
/* The real IO channel. */
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
int inputBuffered, outputBuffered;
/* # bytes held in buffers. */
int result; /* Of device driver operations. */
Tcl_WideInt curPos; /* Position on the device. */
int wasAsync; /* Was the channel nonblocking before the seek
* operation? If so, must restore to
* non-blocking mode after the seek. */
if (CheckChannelErrors(statePtr, TCL_WRITABLE | TCL_READABLE) != 0) {
return -1;
}
/*
* Disallow seek on dead channels - channels that have been closed but not
* yet been deallocated. Such channels can be found if the exit handler
* for channel cleanup has run but the channel is still registered in an
* interpreter.
*/
if (CheckForDeadChannel(NULL, statePtr)) {
return -1;
}
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
/*
* Disallow seek on channels whose type does not have a seek procedure
* defined. This means that the channel does not support seeking.
*/
if (Tcl_ChannelSeekProc(chanPtr->typePtr) == NULL) {
Tcl_SetErrno(EINVAL);
return -1;
}
/*
* Compute how much input and output is buffered. If both input and output
* is buffered, cannot compute the current position.
*/
inputBuffered = Tcl_InputBuffered(chan);
outputBuffered = Tcl_OutputBuffered(chan);
if ((inputBuffered != 0) && (outputBuffered != 0)) {
Tcl_SetErrno(EFAULT);
return -1;
}
/*
* If we are seeking relative to the current position, compute the
* corrected offset taking into account the amount of unread input.
*/
if (mode == SEEK_CUR) {
offset -= inputBuffered;
}
/*
* Discard any queued input - this input should not be read after the
* seek.
*/
DiscardInputQueued(statePtr, 0);
/*
* Reset EOF and BLOCKED flags. We invalidate them by moving the access
* point. Also clear CR related flags.
*/
if (GotFlag(statePtr, CHANNEL_EOF)) {
statePtr->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF | CHANNEL_BLOCKED |
INPUT_SAW_CR);
statePtr->inputEncodingFlags &= ~TCL_ENCODING_END;
/*
* If the channel is in asynchronous output mode, switch it back to
* synchronous mode and cancel any async flush that may be scheduled.
* After the flush, the channel will be put back into asynchronous output
* mode.
*/
wasAsync = 0;
if (GotFlag(statePtr, CHANNEL_NONBLOCKING)) {
wasAsync = 1;
result = StackSetBlockMode(chanPtr, TCL_MODE_BLOCKING);
if (result != 0) {
return -1;
}
ResetFlag(statePtr, CHANNEL_NONBLOCKING);
if (GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
ResetFlag(statePtr, BG_FLUSH_SCHEDULED);
}
}
/*
* If the flush fails we cannot recover the original position. In that
* case the seek is not attempted because we do not know where the access
* position is - instead we return the error. FlushChannel has already
* called Tcl_SetErrno() to report the error upwards. If the flush
* succeeds we do the seek also.
*/
if (FlushChannel(NULL, chanPtr, 0) != 0) {
curPos = -1;
} else {
/*
* Now seek to the new position in the channel as requested by the
* caller.
*/
curPos = ChanSeek(chanPtr, offset, mode, &result);
if (curPos == -1) {
Tcl_SetErrno(result);
}
}
/*
* Restore to nonblocking mode if that was the previous behavior.
*
* NOTE: Even if there was an async flush active we do not restore it now
* because we already flushed all the queued output, above.
*/
if (wasAsync) {
SetFlag(statePtr, CHANNEL_NONBLOCKING);
result = StackSetBlockMode(chanPtr, TCL_MODE_NONBLOCKING);
if (result != 0) {
return -1;
}
}
return curPos;
}
/*
*----------------------------------------------------------------------
*
* Tcl_Tell --
*
* Returns the position of the next character to be read/written on this
* channel.
*
* Results:
* A nonnegative integer on success, -1 on failure. If failed, use
* Tcl_GetErrno() to retrieve the POSIX error code for the error that
* occurred.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_WideInt
Tcl_Tell(
Tcl_Channel chan) /* The channel to return pos for. */
{
Channel *chanPtr = (Channel *) chan;
/* The real IO channel. */
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
int inputBuffered, outputBuffered;
/* # bytes held in buffers. */
int result; /* Of calling device driver. */
Tcl_WideInt curPos; /* Position on device. */
if (CheckChannelErrors(statePtr, TCL_WRITABLE | TCL_READABLE) != 0) {
return -1;
}
/*
* Disallow tell on dead channels -- channels that have been closed but
* not yet been deallocated. Such channels can be found if the exit
* handler for channel cleanup has run but the channel is still registered
* in an interpreter.
*/
if (CheckForDeadChannel(NULL, statePtr)) {
return -1;
}
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
/*
* Disallow tell on channels whose type does not have a seek procedure
* defined. This means that the channel does not support seeking.
*/
if (Tcl_ChannelSeekProc(chanPtr->typePtr) == NULL) {
Tcl_SetErrno(EINVAL);
return -1;
}
/*
* Compute how much input and output is buffered. If both input and output
* is buffered, cannot compute the current position.
*/
inputBuffered = Tcl_InputBuffered(chan);
outputBuffered = Tcl_OutputBuffered(chan);
/*
* Get the current position in the device and compute the position where
* the next character will be read or written. Note that we prefer the
* wideSeekProc if that is available and non-NULL...
*/
curPos = ChanSeek(chanPtr, 0, SEEK_CUR, &result);
if (curPos == -1) {
Tcl_SetErrno(result);
return -1;
}
if (inputBuffered != 0) {
return curPos - inputBuffered;
}
return curPos + outputBuffered;
}
/*
*---------------------------------------------------------------------------
*
* Tcl_SeekOld, Tcl_TellOld --
*
* Backward-compatibility versions of the seek/tell interface that do not
* support 64-bit offsets. This interface is not documented or expected
* to be supported indefinitely.
*
* Results:
* As for Tcl_Seek and Tcl_Tell respectively, except truncated to
* whatever value will fit in an 'int'.
*
* Side effects:
* As for Tcl_Seek and Tcl_Tell respectively.
*
*---------------------------------------------------------------------------
*/
int
Tcl_SeekOld(
Tcl_Channel chan, /* The channel on which to seek. */
int offset, /* Offset to seek to. */
int mode) /* Relative to which location to seek? */
{
Tcl_WideInt wOffset, wResult;
wOffset = Tcl_LongAsWide((long) offset);
wResult = Tcl_Seek(chan, wOffset, mode);
return (int) Tcl_WideAsLong(wResult);
}
int
Tcl_TellOld(
Tcl_Channel chan) /* The channel to return pos for. */
{
Tcl_WideInt wResult = Tcl_Tell(chan);
return (int) Tcl_WideAsLong(wResult);
}
/*
*---------------------------------------------------------------------------
*
* Tcl_TruncateChannel --
*
* Truncate a channel to the given length.
*
* Results:
* TCL_OK on success, TCL_ERROR if the operation failed (e.g., is not
* supported by the type of channel, or the underlying OS operation
* failed in some way).
*
* Side effects:
* Seeks the channel to the current location. Sets errno on OS error.
*
*---------------------------------------------------------------------------
*/
int
Tcl_TruncateChannel(
Tcl_Channel chan, /* Channel to truncate. */
Tcl_WideInt length) /* Length to truncate it to. */
{
Channel *chanPtr = (Channel *) chan;
Tcl_DriverTruncateProc *truncateProc =
Tcl_ChannelTruncateProc(chanPtr->typePtr);
int result;
if (truncateProc == NULL) {
/*
* Feature not supported and it's not emulatable. Pretend it's
* returned an EINVAL, a very generic error!
*/
Tcl_SetErrno(EINVAL);
return TCL_ERROR;
}
if (!GotFlag(chanPtr->state, TCL_WRITABLE)) {
/*
* We require that the file was opened of writing. Do that check now
* so that we only flush if we think we're going to succeed.
*/
Tcl_SetErrno(EINVAL);
return TCL_ERROR;
}
/*
* Seek first to force a total flush of all pending buffers and ditch any
* pre-read input data.
*/
WillWrite(chanPtr);
if (WillRead(chanPtr) < 0) {
return TCL_ERROR;
}
/*
* We're all flushed to disk now and we also don't have any unfortunate
* input baggage around either; can truncate with impunity.
*/
result = truncateProc(chanPtr->instanceData, length);
if (result != 0) {
Tcl_SetErrno(result);
return TCL_ERROR;
}
return TCL_OK;
}
/*
*---------------------------------------------------------------------------
*
* CheckChannelErrors --
*
* See if the channel is in an ready state and can perform the desired
* operation.
*
* Results:
* The return value is 0 if the channel is OK, otherwise the return value
* is -1 and errno is set to indicate the error.
*
* Side effects:
* May clear the EOF and/or BLOCKED bits if reading from channel.
*
*---------------------------------------------------------------------------
*/
static int
CheckChannelErrors(
ChannelState *statePtr, /* Channel to check. */
int flags) /* Test if channel supports desired operation:
* TCL_READABLE, TCL_WRITABLE. Also indicates
* Raw read or write for special close
* processing */
{
int direction = flags & (TCL_READABLE|TCL_WRITABLE);
/*
* Check for unreported error.
*/
if (statePtr->unreportedError != 0) {
Tcl_SetErrno(statePtr->unreportedError);
statePtr->unreportedError = 0;
/*
* TIP #219, Tcl Channel Reflection API.
* Move a defered error message back into the channel bypass.
*/
if (statePtr->chanMsg != NULL) {
TclDecrRefCount(statePtr->chanMsg);
}
statePtr->chanMsg = statePtr->unreportedMsg;
statePtr->unreportedMsg = NULL;
return -1;
}
/*
* Only the raw read and write operations are allowed during close in
* order to drain data from stacked channels.
*/
if (GotFlag(statePtr, CHANNEL_CLOSED) && !(flags & CHANNEL_RAW_MODE)) {
Tcl_SetErrno(EACCES);
return -1;
}
/*
* Fail if the channel is not opened for desired operation.
*/
if ((statePtr->flags & direction) == 0) {
Tcl_SetErrno(EACCES);
return -1;
}
/*
* Fail if the channel is in the middle of a background copy.
*
* Don't do this tests for raw channels here or else the chaining in the
* transformation drivers will fail with 'file busy' error instead of
* retrieving and transforming the data to copy.
*/
if (BUSY_STATE(statePtr, flags) && ((flags & CHANNEL_RAW_MODE) == 0)) {
Tcl_SetErrno(EBUSY);
return -1;
}
if (direction == TCL_READABLE) {
ResetFlag(statePtr, CHANNEL_NEED_MORE_DATA);
}
return 0;
}
/*
*----------------------------------------------------------------------
*
* Tcl_Eof --
*
* Returns 1 if the channel is at EOF, 0 otherwise.
*
* Results:
* 1 or 0, always.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_Eof(
Tcl_Channel chan) /* Does this channel have EOF? */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of real channel structure. */
return GotFlag(statePtr, CHANNEL_EOF) ? 1 : 0;
}
/*
*----------------------------------------------------------------------
*
* Tcl_InputBlocked --
*
* Returns 1 if input is blocked on this channel, 0 otherwise.
*
* Results:
* 0 or 1, always.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_InputBlocked(
Tcl_Channel chan) /* Is this channel blocked? */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of real channel structure. */
return GotFlag(statePtr, CHANNEL_BLOCKED) ? 1 : 0;
}
/*
*----------------------------------------------------------------------
*
* Tcl_InputBuffered --
*
* Returns the number of bytes of input currently buffered in the common
* internal buffer of a channel.
*
* Results:
* The number of input bytes buffered, or zero if the channel is not open
* for reading.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_InputBuffered(
Tcl_Channel chan) /* The channel to query. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of real channel structure. */
ChannelBuffer *bufPtr;
int bytesBuffered;
for (bytesBuffered = 0, bufPtr = statePtr->inQueueHead; bufPtr != NULL;
bufPtr = bufPtr->nextPtr) {
bytesBuffered += BytesLeft(bufPtr);
}
/*
* Don't forget the bytes in the topmost pushback area.
*/
for (bufPtr = statePtr->topChanPtr->inQueueHead; bufPtr != NULL;
bufPtr = bufPtr->nextPtr) {
bytesBuffered += BytesLeft(bufPtr);
}
return bytesBuffered;
}
/*
*----------------------------------------------------------------------
*
* Tcl_OutputBuffered --
*
* Returns the number of bytes of output currently buffered in the common
* internal buffer of a channel.
*
* Results:
* The number of output bytes buffered, or zero if the channel is not open
* for writing.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_OutputBuffered(
Tcl_Channel chan) /* The channel to query. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of real channel structure. */
ChannelBuffer *bufPtr;
int bytesBuffered;
for (bytesBuffered = 0, bufPtr = statePtr->outQueueHead; bufPtr != NULL;
bufPtr = bufPtr->nextPtr) {
bytesBuffered += BytesLeft(bufPtr);
}
if (statePtr->curOutPtr != NULL) {
ChannelBuffer *curOutPtr = statePtr->curOutPtr;
if (IsBufferReady(curOutPtr)) {
bytesBuffered += BytesLeft(curOutPtr);
}
}
return bytesBuffered;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelBuffered --
*
* Returns the number of bytes of input currently buffered in the
* internal buffer (push back area) of a channel.
*
* Results:
* The number of input bytes buffered, or zero if the channel is not open
* for reading.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_ChannelBuffered(
Tcl_Channel chan) /* The channel to query. */
{
Channel *chanPtr = (Channel *) chan;
/* Real channel structure. */
ChannelBuffer *bufPtr;
int bytesBuffered = 0;
for (bufPtr = chanPtr->inQueueHead; bufPtr != NULL;
bufPtr = bufPtr->nextPtr) {
bytesBuffered += BytesLeft(bufPtr);
}
return bytesBuffered;
}
/*
*----------------------------------------------------------------------
*
* Tcl_SetChannelBufferSize --
*
* Sets the size of buffers to allocate to store input or output in the
* channel. The size must be between 1 byte and 1 MByte.
*
* Results:
* None.
*
* Side effects:
* Sets the size of buffers subsequently allocated for this channel.
*
*----------------------------------------------------------------------
*/
void
Tcl_SetChannelBufferSize(
Tcl_Channel chan, /* The channel whose buffer size to set. */
int sz) /* The size to set. */
{
ChannelState *statePtr; /* State of real channel structure. */
/*
* Clip the buffer size to force it into the [1,1M] range
*/
if (sz < 1) {
sz = 1;
} else if (sz > MAX_CHANNEL_BUFFER_SIZE) {
sz = MAX_CHANNEL_BUFFER_SIZE;
}
statePtr = ((Channel *) chan)->state;
if (statePtr->bufSize == sz) {
return;
}
statePtr->bufSize = sz;
/*
* If bufsize changes, need to get rid of old utility buffer.
*/
if (statePtr->saveInBufPtr != NULL) {
RecycleBuffer(statePtr, statePtr->saveInBufPtr, 1);
statePtr->saveInBufPtr = NULL;
}
if ((statePtr->inQueueHead != NULL)
&& (statePtr->inQueueHead->nextPtr == NULL)
&& IsBufferEmpty(statePtr->inQueueHead)) {
RecycleBuffer(statePtr, statePtr->inQueueHead, 1);
statePtr->inQueueHead = NULL;
statePtr->inQueueTail = NULL;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelBufferSize --
*
* Retrieves the size of buffers to allocate for this channel.
*
* Results:
* The size.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_GetChannelBufferSize(
Tcl_Channel chan) /* The channel for which to find the buffer
* size. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of real channel structure. */
return statePtr->bufSize;
}
/*
*----------------------------------------------------------------------
*
* Tcl_BadChannelOption --
*
* This procedure generates a "bad option" error message in an (optional)
* interpreter. It is used by channel drivers when a invalid Set/Get
* option is requested. Its purpose is to concatenate the generic options
* list to the specific ones and factorize the generic options error
* message string.
*
* Results:
* TCL_ERROR.
*
* Side effects:
* An error message is generated in interp's result object to indicate
* that a command was invoked with the a bad option. The message has the
* form:
* bad option "blah": should be one of
* <...generic options...>+<...specific options...>
* "blah" is the optionName argument and "<specific options>" is a space
* separated list of specific option words. The function takes good care
* of inserting minus signs before each option, commas after, and an "or"
* before the last option.
*
*----------------------------------------------------------------------
*/
int
Tcl_BadChannelOption(
Tcl_Interp *interp, /* Current interpreter (can be NULL).*/
const char *optionName, /* 'bad option' name */
const char *optionList) /* Specific options list to append to the
* standard generic options. Can be NULL for
* generic options only. */
{
if (interp != NULL) {
const char *genericopt =
"blocking buffering buffersize encoding eofchar translation";
const char **argv;
int argc, i;
Tcl_DString ds;
Tcl_Obj *errObj;
Tcl_DStringInit(&ds);
Tcl_DStringAppend(&ds, genericopt, -1);
if (optionList && (*optionList)) {
TclDStringAppendLiteral(&ds, " ");
Tcl_DStringAppend(&ds, optionList, -1);
}
if (Tcl_SplitList(interp, Tcl_DStringValue(&ds),
&argc, &argv) != TCL_OK) {
Tcl_Panic("malformed option list in channel driver");
}
Tcl_ResetResult(interp);
errObj = Tcl_ObjPrintf("bad option \"%s\": should be one of ",
optionName ? optionName : "");
argc--;
for (i = 0; i < argc; i++) {
Tcl_AppendPrintfToObj(errObj, "-%s, ", argv[i]);
}
Tcl_AppendPrintfToObj(errObj, "or -%s", argv[i]);
Tcl_SetObjResult(interp, errObj);
Tcl_DStringFree(&ds);
ckfree(argv);
}
Tcl_SetErrno(EINVAL);
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelOption --
*
* Gets a mode associated with an IO channel. If the optionName arg is
* non NULL, retrieves the value of that option. If the optionName arg is
* NULL, retrieves a list of alternating option names and values for the
* given channel.
*
* Results:
* A standard Tcl result. Also sets the supplied DString to the string
* value of the option(s) returned.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_GetChannelOption(
Tcl_Interp *interp, /* For error reporting - can be NULL. */
Tcl_Channel chan, /* Channel on which to get option. */
const char *optionName, /* Option to get. */
Tcl_DString *dsPtr) /* Where to store value(s). */
{
size_t len; /* Length of optionName string. */
char optionVal[128]; /* Buffer for sprintf. */
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
int flags;
/*
* Disallow options on dead channels -- channels that have been closed but
* not yet been deallocated. Such channels can be found if the exit
* handler for channel cleanup has run but the channel is still registered
* in an interpreter.
*/
if (CheckForDeadChannel(interp, statePtr)) {
return TCL_ERROR;
}
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
/*
* If we are in the middle of a background copy, use the saved flags.
*/
if (statePtr->csPtrR) {
flags = statePtr->csPtrR->readFlags;
} else if (statePtr->csPtrW) {
flags = statePtr->csPtrW->writeFlags;
} else {
flags = statePtr->flags;
}
/*
* If the optionName is NULL it means that we want a list of all options
* and values.
*/
if (optionName == NULL) {
len = 0;
} else {
len = strlen(optionName);
}
if (len == 0 || HaveOpt(2, "-blocking")) {
if (len == 0) {
Tcl_DStringAppendElement(dsPtr, "-blocking");
}
Tcl_DStringAppendElement(dsPtr,
(flags & CHANNEL_NONBLOCKING) ? "0" : "1");
if (len > 0) {
return TCL_OK;
}
}
if (len == 0 || HaveOpt(7, "-buffering")) {
if (len == 0) {
Tcl_DStringAppendElement(dsPtr, "-buffering");
}
if (flags & CHANNEL_LINEBUFFERED) {
Tcl_DStringAppendElement(dsPtr, "line");
} else if (flags & CHANNEL_UNBUFFERED) {
Tcl_DStringAppendElement(dsPtr, "none");
} else {
Tcl_DStringAppendElement(dsPtr, "full");
}
if (len > 0) {
return TCL_OK;
}
}
if (len == 0 || HaveOpt(7, "-buffersize")) {
if (len == 0) {
Tcl_DStringAppendElement(dsPtr, "-buffersize");
}
TclFormatInt(optionVal, statePtr->bufSize);
Tcl_DStringAppendElement(dsPtr, optionVal);
if (len > 0) {
return TCL_OK;
}
}
if (len == 0 || HaveOpt(2, "-encoding")) {
if (len == 0) {
Tcl_DStringAppendElement(dsPtr, "-encoding");
}
if (statePtr->encoding == NULL) {
Tcl_DStringAppendElement(dsPtr, "binary");
} else {
Tcl_DStringAppendElement(dsPtr,
Tcl_GetEncodingName(statePtr->encoding));
}
if (len > 0) {
return TCL_OK;
}
}
if (len == 0 || HaveOpt(2, "-eofchar")) {
if (len == 0) {
Tcl_DStringAppendElement(dsPtr, "-eofchar");
}
if (((flags & (TCL_READABLE|TCL_WRITABLE)) ==
(TCL_READABLE|TCL_WRITABLE)) && (len == 0)) {
Tcl_DStringStartSublist(dsPtr);
}
if (flags & TCL_READABLE) {
if (statePtr->inEofChar == 0) {
Tcl_DStringAppendElement(dsPtr, "");
} else {
char buf[4];
sprintf(buf, "%c", statePtr->inEofChar);
Tcl_DStringAppendElement(dsPtr, buf);
}
}
if (flags & TCL_WRITABLE) {
if (statePtr->outEofChar == 0) {
Tcl_DStringAppendElement(dsPtr, "");
} else {
char buf[4];
sprintf(buf, "%c", statePtr->outEofChar);
Tcl_DStringAppendElement(dsPtr, buf);
}
}
if (!(flags & (TCL_READABLE|TCL_WRITABLE))) {
/*
* Not readable or writable (e.g. server socket)
*/
Tcl_DStringAppendElement(dsPtr, "");
}
if (((flags & (TCL_READABLE|TCL_WRITABLE)) ==
(TCL_READABLE|TCL_WRITABLE)) && (len == 0)) {
Tcl_DStringEndSublist(dsPtr);
}
if (len > 0) {
return TCL_OK;
}
}
if (len == 0 || HaveOpt(1, "-translation")) {
if (len == 0) {
Tcl_DStringAppendElement(dsPtr, "-translation");
}
if (((flags & (TCL_READABLE|TCL_WRITABLE)) ==
(TCL_READABLE|TCL_WRITABLE)) && (len == 0)) {
Tcl_DStringStartSublist(dsPtr);
}
if (flags & TCL_READABLE) {
if (statePtr->inputTranslation == TCL_TRANSLATE_AUTO) {
Tcl_DStringAppendElement(dsPtr, "auto");
} else if (statePtr->inputTranslation == TCL_TRANSLATE_CR) {
Tcl_DStringAppendElement(dsPtr, "cr");
} else if (statePtr->inputTranslation == TCL_TRANSLATE_CRLF) {
Tcl_DStringAppendElement(dsPtr, "crlf");
} else {
Tcl_DStringAppendElement(dsPtr, "lf");
}
}
if (flags & TCL_WRITABLE) {
if (statePtr->outputTranslation == TCL_TRANSLATE_AUTO) {
Tcl_DStringAppendElement(dsPtr, "auto");
} else if (statePtr->outputTranslation == TCL_TRANSLATE_CR) {
Tcl_DStringAppendElement(dsPtr, "cr");
} else if (statePtr->outputTranslation == TCL_TRANSLATE_CRLF) {
Tcl_DStringAppendElement(dsPtr, "crlf");
} else {
Tcl_DStringAppendElement(dsPtr, "lf");
}
}
if (!(flags & (TCL_READABLE|TCL_WRITABLE))) {
/*
* Not readable or writable (e.g. server socket)
*/
Tcl_DStringAppendElement(dsPtr, "auto");
}
if (((flags & (TCL_READABLE|TCL_WRITABLE)) ==
(TCL_READABLE|TCL_WRITABLE)) && (len == 0)) {
Tcl_DStringEndSublist(dsPtr);
}
if (len > 0) {
return TCL_OK;
}
}
if (chanPtr->typePtr->getOptionProc != NULL) {
/*
* Let the driver specific handle additional options and result code
* and message.
*/
return chanPtr->typePtr->getOptionProc(chanPtr->instanceData, interp,
optionName, dsPtr);
} else {
/*
* No driver specific options case.
*/
if (len == 0) {
return TCL_OK;
}
return Tcl_BadChannelOption(interp, optionName, NULL);
}
}
/*
*---------------------------------------------------------------------------
*
* Tcl_SetChannelOption --
*
* Sets an option on a channel.
*
* Results:
* A standard Tcl result. On error, sets interp's result object if
* interp is not NULL.
*
* Side effects:
* May modify an option on a device.
*
*---------------------------------------------------------------------------
*/
int
Tcl_SetChannelOption(
Tcl_Interp *interp, /* For error reporting - can be NULL. */
Tcl_Channel chan, /* Channel on which to set mode. */
const char *optionName, /* Which option to set? */
const char *newValue) /* New value for option. */
{
Channel *chanPtr = (Channel *) chan;
/* The real IO channel. */
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
size_t len; /* Length of optionName string. */
int argc;
const char **argv;
/*
* If the channel is in the middle of a background copy, fail.
*/
if (statePtr->csPtrR || statePtr->csPtrW) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"unable to set channel options: background copy in"
" progress", -1));
}
return TCL_ERROR;
}
/*
* Disallow options on dead channels -- channels that have been closed but
* not yet been deallocated. Such channels can be found if the exit
* handler for channel cleanup has run but the channel is still registered
* in an interpreter.
*/
if (CheckForDeadChannel(NULL, statePtr)) {
return TCL_ERROR;
}
/*
* This operation should occur at the top of a channel stack.
*/
chanPtr = statePtr->topChanPtr;
len = strlen(optionName);
if (HaveOpt(2, "-blocking")) {
int newMode;
if (Tcl_GetBoolean(interp, newValue, &newMode) == TCL_ERROR) {
return TCL_ERROR;
}
if (newMode) {
newMode = TCL_MODE_BLOCKING;
} else {
newMode = TCL_MODE_NONBLOCKING;
}
return SetBlockMode(interp, chanPtr, newMode);
} else if (HaveOpt(7, "-buffering")) {
len = strlen(newValue);
if ((newValue[0] == 'f') && (strncmp(newValue, "full", len) == 0)) {
ResetFlag(statePtr, CHANNEL_UNBUFFERED | CHANNEL_LINEBUFFERED);
} else if ((newValue[0] == 'l') &&
(strncmp(newValue, "line", len) == 0)) {
ResetFlag(statePtr, CHANNEL_UNBUFFERED);
SetFlag(statePtr, CHANNEL_LINEBUFFERED);
} else if ((newValue[0] == 'n') &&
(strncmp(newValue, "none", len) == 0)) {
ResetFlag(statePtr, CHANNEL_LINEBUFFERED);
SetFlag(statePtr, CHANNEL_UNBUFFERED);
} else if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"bad value for -buffering: must be one of"
" full, line, or none", -1));
return TCL_ERROR;
}
return TCL_OK;
} else if (HaveOpt(7, "-buffersize")) {
int newBufferSize;
if (Tcl_GetInt(interp, newValue, &newBufferSize) == TCL_ERROR) {
return TCL_ERROR;
}
Tcl_SetChannelBufferSize(chan, newBufferSize);
return TCL_OK;
} else if (HaveOpt(2, "-encoding")) {
Tcl_Encoding encoding;
if ((newValue[0] == '\0') || (strcmp(newValue, "binary") == 0)) {
encoding = NULL;
} else {
encoding = Tcl_GetEncoding(interp, newValue);
if (encoding == NULL) {
return TCL_ERROR;
}
}
/*
* When the channel has an escape sequence driven encoding such as
* iso2022, the terminated escape sequence must write to the buffer.
*/
if ((statePtr->encoding != NULL)
&& !(statePtr->outputEncodingFlags & TCL_ENCODING_START)
&& (CheckChannelErrors(statePtr, TCL_WRITABLE) == 0)) {
statePtr->outputEncodingFlags |= TCL_ENCODING_END;
WriteChars(chanPtr, "", 0);
}
Tcl_FreeEncoding(statePtr->encoding);
statePtr->encoding = encoding;
statePtr->inputEncodingState = NULL;
statePtr->inputEncodingFlags = TCL_ENCODING_START;
statePtr->outputEncodingState = NULL;
statePtr->outputEncodingFlags = TCL_ENCODING_START;
ResetFlag(statePtr, CHANNEL_NEED_MORE_DATA);
UpdateInterest(chanPtr);
return TCL_OK;
} else if (HaveOpt(2, "-eofchar")) {
if (Tcl_SplitList(interp, newValue, &argc, &argv) == TCL_ERROR) {
return TCL_ERROR;
}
if (argc == 0) {
statePtr->inEofChar = 0;
statePtr->outEofChar = 0;
} else if (argc == 1 || argc == 2) {
int outIndex = (argc - 1);
int inValue = (int) argv[0][0];
int outValue = (int) argv[outIndex][0];
if (inValue & 0x80 || outValue & 0x80) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"bad value for -eofchar: must be non-NUL ASCII"
" character", -1));
}
ckfree(argv);
return TCL_ERROR;
}
if (GotFlag(statePtr, TCL_READABLE)) {
statePtr->inEofChar = inValue;
}
if (GotFlag(statePtr, TCL_WRITABLE)) {
statePtr->outEofChar = outValue;
}
} else {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"bad value for -eofchar: should be a list of zero,"
" one, or two elements", -1));
}
ckfree(argv);
return TCL_ERROR;
}
if (argv != NULL) {
ckfree(argv);
}
/*
* [Bug 930851] Reset EOF and BLOCKED flags. Changing the character
* which signals eof can transform a current eof condition into a 'go
* ahead'. Ditto for blocked.
*/
if (GotFlag(statePtr, CHANNEL_EOF)) {
statePtr->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(statePtr, CHANNEL_EOF|CHANNEL_STICKY_EOF|CHANNEL_BLOCKED);
statePtr->inputEncodingFlags &= ~TCL_ENCODING_END;
return TCL_OK;
} else if (HaveOpt(1, "-translation")) {
const char *readMode, *writeMode;
if (Tcl_SplitList(interp, newValue, &argc, &argv) == TCL_ERROR) {
return TCL_ERROR;
}
if (argc == 1) {
readMode = GotFlag(statePtr, TCL_READABLE) ? argv[0] : NULL;
writeMode = GotFlag(statePtr, TCL_WRITABLE) ? argv[0] : NULL;
} else if (argc == 2) {
readMode = GotFlag(statePtr, TCL_READABLE) ? argv[0] : NULL;
writeMode = GotFlag(statePtr, TCL_WRITABLE) ? argv[1] : NULL;
} else {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"bad value for -translation: must be a one or two"
" element list", -1));
}
ckfree(argv);
return TCL_ERROR;
}
if (readMode) {
TclEolTranslation translation;
if (*readMode == '\0') {
translation = statePtr->inputTranslation;
} else if (strcmp(readMode, "auto") == 0) {
translation = TCL_TRANSLATE_AUTO;
} else if (strcmp(readMode, "binary") == 0) {
translation = TCL_TRANSLATE_LF;
statePtr->inEofChar = 0;
Tcl_FreeEncoding(statePtr->encoding);
statePtr->encoding = NULL;
} else if (strcmp(readMode, "lf") == 0) {
translation = TCL_TRANSLATE_LF;
} else if (strcmp(readMode, "cr") == 0) {
translation = TCL_TRANSLATE_CR;
} else if (strcmp(readMode, "crlf") == 0) {
translation = TCL_TRANSLATE_CRLF;
} else if (strcmp(readMode, "platform") == 0) {
translation = TCL_PLATFORM_TRANSLATION;
} else {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"bad value for -translation: must be one of "
"auto, binary, cr, lf, crlf, or platform", -1));
}
ckfree(argv);
return TCL_ERROR;
}
/*
* Reset the EOL flags since we need to look at any buffered data
* to see if the new translation mode allows us to complete the
* line.
*/
if (translation != statePtr->inputTranslation) {
statePtr->inputTranslation = translation;
ResetFlag(statePtr, INPUT_SAW_CR | CHANNEL_NEED_MORE_DATA);
UpdateInterest(chanPtr);
}
}
if (writeMode) {
if (*writeMode == '\0') {
/* Do nothing. */
} else if (strcmp(writeMode, "auto") == 0) {
/*
* This is a hack to get TCP sockets to produce output in CRLF
* mode if they are being set into AUTO mode. A better
* solution for achieving this effect will be coded later.
*/
if (strcmp(Tcl_ChannelName(chanPtr->typePtr), "tcp") == 0) {
statePtr->outputTranslation = TCL_TRANSLATE_CRLF;
} else {
statePtr->outputTranslation = TCL_PLATFORM_TRANSLATION;
}
} else if (strcmp(writeMode, "binary") == 0) {
statePtr->outEofChar = 0;
statePtr->outputTranslation = TCL_TRANSLATE_LF;
Tcl_FreeEncoding(statePtr->encoding);
statePtr->encoding = NULL;
} else if (strcmp(writeMode, "lf") == 0) {
statePtr->outputTranslation = TCL_TRANSLATE_LF;
} else if (strcmp(writeMode, "cr") == 0) {
statePtr->outputTranslation = TCL_TRANSLATE_CR;
} else if (strcmp(writeMode, "crlf") == 0) {
statePtr->outputTranslation = TCL_TRANSLATE_CRLF;
} else if (strcmp(writeMode, "platform") == 0) {
statePtr->outputTranslation = TCL_PLATFORM_TRANSLATION;
} else {
if (interp) {
Tcl_SetObjResult(interp, Tcl_NewStringObj(
"bad value for -translation: must be one of "
"auto, binary, cr, lf, crlf, or platform", -1));
}
ckfree(argv);
return TCL_ERROR;
}
}
ckfree(argv);
return TCL_OK;
} else if (chanPtr->typePtr->setOptionProc != NULL) {
return chanPtr->typePtr->setOptionProc(chanPtr->instanceData, interp,
optionName, newValue);
} else {
return Tcl_BadChannelOption(interp, optionName, NULL);
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* CleanupChannelHandlers --
*
* Removes channel handlers that refer to the supplied interpreter, so
* that if the actual channel is not closed now, these handlers will not
* run on subsequent events on the channel. This would be erroneous,
* because the interpreter no longer has a reference to this channel.
*
* Results:
* None.
*
* Side effects:
* Removes channel handlers.
*
*----------------------------------------------------------------------
*/
static void
CleanupChannelHandlers(
Tcl_Interp *interp,
Channel *chanPtr)
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
EventScriptRecord *sPtr, *prevPtr, *nextPtr;
/*
* Remove fileevent records on this channel that refer to the given
* interpreter.
*/
for (sPtr = statePtr->scriptRecordPtr, prevPtr = NULL;
sPtr != NULL; sPtr = nextPtr) {
nextPtr = sPtr->nextPtr;
if (sPtr->interp == interp) {
if (prevPtr == NULL) {
statePtr->scriptRecordPtr = nextPtr;
} else {
prevPtr->nextPtr = nextPtr;
}
Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr,
TclChannelEventScriptInvoker, sPtr);
TclDecrRefCount(sPtr->scriptPtr);
ckfree(sPtr);
} else {
prevPtr = sPtr;
}
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_NotifyChannel --
*
* This procedure is called by a channel driver when a driver detects an
* event on a channel. This procedure is responsible for actually
* handling the event by invoking any channel handler callbacks.
*
* Results:
* None.
*
* Side effects:
* Whatever the channel handler callback procedure does.
*
*----------------------------------------------------------------------
*/
void
Tcl_NotifyChannel(
Tcl_Channel channel, /* Channel that detected an event. */
int mask) /* OR'ed combination of TCL_READABLE,
* TCL_WRITABLE, or TCL_EXCEPTION: indicates
* which events were detected. */
{
Channel *chanPtr = (Channel *) channel;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
ChannelHandler *chPtr;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
NextChannelHandler nh;
Channel *upChanPtr;
const Tcl_ChannelType *upTypePtr;
/*
* In contrast to the other API functions this procedure walks towards the
* top of a stack and not down from it.
*
* The channel calling this procedure is the one who generated the event,
* and thus does not take part in handling it. IOW, its HandlerProc is not
* called, instead we begin with the channel above it.
*
* This behaviour also allows the transformation channels to generate
* their own events and pass them upward.
*/
while (mask && (chanPtr->upChanPtr != NULL)) {
Tcl_DriverHandlerProc *upHandlerProc;
upChanPtr = chanPtr->upChanPtr;
upTypePtr = upChanPtr->typePtr;
upHandlerProc = Tcl_ChannelHandlerProc(upTypePtr);
if (upHandlerProc != NULL) {
mask = upHandlerProc(upChanPtr->instanceData, mask);
}
/*
* ELSE: Ignore transformations which are unable to handle the event
* coming from below. Assume that they don't change the mask and pass
* it on.
*/
chanPtr = upChanPtr;
}
channel = (Tcl_Channel) chanPtr;
/*
* Here we have either reached the top of the stack or the mask is empty.
* We break out of the procedure if it is the latter.
*/
if (!mask) {
return;
}
/*
* We are now above the topmost channel in a stack and have events left.
* Now call the channel handlers as usual.
*
* Preserve the channel struct in case the script closes it.
*/
TclChannelPreserve((Tcl_Channel)channel);
Tcl_Preserve(statePtr);
/*
* Avoid processing if the channel owner has been changed.
*/
if (statePtr->managingThread != Tcl_GetCurrentThread()) {
goto done;
}
/*
* If we are flushing in the background, be sure to call FlushChannel for
* writable events. Note that we have to discard the writable event so we
* don't call any write handlers before the flush is complete.
*/
if (GotFlag(statePtr, BG_FLUSH_SCHEDULED) && (mask & TCL_WRITABLE)) {
if (0 == FlushChannel(NULL, chanPtr, 1)) {
mask &= ~TCL_WRITABLE;
}
}
/*
* Add this invocation to the list of recursive invocations of
* Tcl_NotifyChannel.
*/
nh.nextHandlerPtr = NULL;
nh.nestedHandlerPtr = tsdPtr->nestedHandlerPtr;
tsdPtr->nestedHandlerPtr = &nh;
for (chPtr = statePtr->chPtr; chPtr != NULL; ) {
/*
* If this channel handler is interested in any of the events that
* have occurred on the channel, invoke its procedure.
*/
if ((chPtr->mask & mask) != 0) {
nh.nextHandlerPtr = chPtr->nextPtr;
chPtr->proc(chPtr->clientData, chPtr->mask & mask);
chPtr = nh.nextHandlerPtr;
} else {
chPtr = chPtr->nextPtr;
}
/*
* Stop if the channel owner has been changed in-between.
*/
if (chanPtr->state->managingThread != Tcl_GetCurrentThread()) {
goto done;
}
}
/*
* Update the notifier interest, since it may have changed after invoking
* event handlers. Skip that if the channel was deleted in the call to the
* channel handler.
*/
if (chanPtr->typePtr != NULL) {
/*
* TODO: This call may not be needed. If a handler induced a
* change in interest, that handler should have made its own
* UpdateInterest() call, one would think.
*/
UpdateInterest(chanPtr);
}
done:
Tcl_Release(statePtr);
TclChannelRelease(channel);
tsdPtr->nestedHandlerPtr = nh.nestedHandlerPtr;
}
/*
*----------------------------------------------------------------------
*
* UpdateInterest --
*
* Arrange for the notifier to call us back at appropriate times based on
* the current state of the channel.
*
* Results:
* None.
*
* Side effects:
* May schedule a timer or driver handler.
*
*----------------------------------------------------------------------
*/
static void
UpdateInterest(
Channel *chanPtr) /* Channel to update. */
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
int mask = statePtr->interestMask;
if (chanPtr->typePtr == NULL) {
/* Do not update interest on a closed channel */
return;
}
/*
* If there are flushed buffers waiting to be written, then we need to
* watch for the channel to become writable.
*/
if (GotFlag(statePtr, BG_FLUSH_SCHEDULED)) {
mask |= TCL_WRITABLE;
}
/*
* If there is data in the input queue, and we aren't waiting for more
* data, then we need to schedule a timer so we don't block in the
* notifier. Also, cancel the read interest so we don't get duplicate
* events.
*/
if (mask & TCL_READABLE) {
if (!GotFlag(statePtr, CHANNEL_NEED_MORE_DATA)
&& (statePtr->inQueueHead != NULL)
&& IsBufferReady(statePtr->inQueueHead)) {
mask &= ~TCL_READABLE;
/*
* Andreas Kupries, April 11, 2003
*
* Some operating systems (Solaris 2.6 and higher (but not Solaris
* 2.5, go figure)) generate READABLE and EXCEPTION events when
* select()'ing [*] on a plain file, even if EOF was not yet
* reached. This is a problem in the following situation:
*
* - An extension asks to get both READABLE and EXCEPTION events.
* - It reads data into a buffer smaller than the buffer used by
* Tcl itself.
* - It does not process all events in the event queue, but only
* one, at least in some situations.
*
* In that case we can get into a situation where
*
* - Tcl drops READABLE here, because it has data in its own
* buffers waiting to be read by the extension.
* - A READABLE event is synthesized via timer.
* - The OS still reports the EXCEPTION condition on the file.
* - And the extension gets the EXCEPTION event first, and handles
* this as EOF.
*
* End result ==> Premature end of reading from a file.
*
* The concrete example is 'Expect', and its [expect] command
* (and at the C-level, deep in the bowels of Expect,
* 'exp_get_next_event'. See marker 'SunOS' for commentary in
* that function too).
*
* [*] As the Tcl notifier does. See also for marker 'SunOS' in
* file 'exp_event.c' of Expect.
*
* Our solution here is to drop the interest in the EXCEPTION
* events too. This compiles on all platforms, and also passes the
* testsuite on all of them.
*/
mask &= ~TCL_EXCEPTION;
if (!statePtr->timer) {
statePtr->timer = Tcl_CreateTimerHandler(SYNTHETIC_EVENT_TIME,
ChannelTimerProc, chanPtr);
}
}
}
ChanWatch(chanPtr, mask);
}
/*
*----------------------------------------------------------------------
*
* ChannelTimerProc --
*
* Timer handler scheduled by UpdateInterest to monitor the channel
* buffers until they are empty.
*
* Results:
* None.
*
* Side effects:
* May invoke channel handlers.
*
*----------------------------------------------------------------------
*/
static void
ChannelTimerProc(
ClientData clientData)
{
Channel *chanPtr = (Channel *)clientData;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
if (!GotFlag(statePtr, CHANNEL_NEED_MORE_DATA)
&& (statePtr->interestMask & TCL_READABLE)
&& (statePtr->inQueueHead != NULL)
&& IsBufferReady(statePtr->inQueueHead)) {
/*
* Restart the timer in case a channel handler reenters the event loop
* before UpdateInterest gets called by Tcl_NotifyChannel.
*/
statePtr->timer = Tcl_CreateTimerHandler(SYNTHETIC_EVENT_TIME,
ChannelTimerProc,chanPtr);
Tcl_Preserve(statePtr);
Tcl_NotifyChannel((Tcl_Channel) chanPtr, TCL_READABLE);
Tcl_Release(statePtr);
} else {
statePtr->timer = NULL;
UpdateInterest(chanPtr);
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_CreateChannelHandler --
*
* Arrange for a given procedure to be invoked whenever the channel
* indicated by the chanPtr arg becomes readable or writable.
*
* Results:
* None.
*
* Side effects:
* From now on, whenever the I/O channel given by chanPtr becomes ready
* in the way indicated by mask, proc will be invoked. See the manual
* entry for details on the calling sequence to proc. If there is already
* an event handler for chan, proc and clientData, then the mask will be
* updated.
*
*----------------------------------------------------------------------
*/
void
Tcl_CreateChannelHandler(
Tcl_Channel chan, /* The channel to create the handler for. */
int mask, /* OR'ed combination of TCL_READABLE,
* TCL_WRITABLE, and TCL_EXCEPTION: indicates
* conditions under which proc should be
* called. Use 0 to disable a registered
* handler. */
Tcl_ChannelProc *proc, /* Procedure to call for each selected
* event. */
ClientData clientData) /* Arbitrary data to pass to proc. */
{
ChannelHandler *chPtr;
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
/*
* Check whether this channel handler is not already registered. If it is
* not, create a new record, else reuse existing record (smash current
* values).
*/
for (chPtr = statePtr->chPtr; chPtr != NULL; chPtr = chPtr->nextPtr) {
if ((chPtr->chanPtr == chanPtr) && (chPtr->proc == proc) &&
(chPtr->clientData == clientData)) {
break;
}
}
if (chPtr == NULL) {
chPtr = (ChannelHandler *)ckalloc(sizeof(ChannelHandler));
chPtr->mask = 0;
chPtr->proc = proc;
chPtr->clientData = clientData;
chPtr->chanPtr = chanPtr;
chPtr->nextPtr = statePtr->chPtr;
statePtr->chPtr = chPtr;
}
/*
* The remainder of the initialization below is done regardless of whether
* or not this is a new record or a modification of an old one.
*/
chPtr->mask = mask;
/*
* Recompute the interest mask for the channel - this call may actually be
* disabling an existing handler.
*/
statePtr->interestMask = 0;
for (chPtr = statePtr->chPtr; chPtr != NULL; chPtr = chPtr->nextPtr) {
statePtr->interestMask |= chPtr->mask;
}
UpdateInterest(statePtr->topChanPtr);
}
/*
*----------------------------------------------------------------------
*
* Tcl_DeleteChannelHandler --
*
* Cancel a previously arranged callback arrangement for an IO channel.
*
* Results:
* None.
*
* Side effects:
* If a callback was previously registered for this chan, proc and
* clientData, it is removed and the callback will no longer be called
* when the channel becomes ready for IO.
*
*----------------------------------------------------------------------
*/
void
Tcl_DeleteChannelHandler(
Tcl_Channel chan, /* The channel for which to remove the
* callback. */
Tcl_ChannelProc *proc, /* The procedure in the callback to delete. */
ClientData clientData) /* The client data in the callback to
* delete. */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
ChannelHandler *chPtr, *prevChPtr;
Channel *chanPtr = (Channel *) chan;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
NextChannelHandler *nhPtr;
/*
* Find the entry and the previous one in the list.
*/
for (prevChPtr = NULL, chPtr = statePtr->chPtr; chPtr != NULL;
chPtr = chPtr->nextPtr) {
if ((chPtr->chanPtr == chanPtr) && (chPtr->clientData == clientData)
&& (chPtr->proc == proc)) {
break;
}
prevChPtr = chPtr;
}
/*
* If not found, return without doing anything.
*/
if (chPtr == NULL) {
return;
}
/*
* If Tcl_NotifyChannel is about to process this handler, tell it to
* process the next one instead - we are going to delete *this* one.
*/
for (nhPtr = tsdPtr->nestedHandlerPtr; nhPtr != NULL;
nhPtr = nhPtr->nestedHandlerPtr) {
if (nhPtr->nextHandlerPtr == chPtr) {
nhPtr->nextHandlerPtr = chPtr->nextPtr;
}
}
/*
* Splice it out of the list of channel handlers.
*/
if (prevChPtr == NULL) {
statePtr->chPtr = chPtr->nextPtr;
} else {
prevChPtr->nextPtr = chPtr->nextPtr;
}
ckfree(chPtr);
/*
* Recompute the interest list for the channel, so that infinite loops
* will not result if Tcl_DeleteChannelHandler is called inside an event.
*/
statePtr->interestMask = 0;
for (chPtr = statePtr->chPtr; chPtr != NULL; chPtr = chPtr->nextPtr) {
statePtr->interestMask |= chPtr->mask;
}
UpdateInterest(statePtr->topChanPtr);
}
/*
*----------------------------------------------------------------------
*
* DeleteScriptRecord --
*
* Delete a script record for this combination of channel, interp and
* mask.
*
* Results:
* None.
*
* Side effects:
* Deletes a script record and cancels a channel event handler.
*
*----------------------------------------------------------------------
*/
static void
DeleteScriptRecord(
Tcl_Interp *interp, /* Interpreter in which script was to be
* executed. */
Channel *chanPtr, /* The channel for which to delete the script
* record (if any). */
int mask) /* Events in mask must exactly match mask of
* script to delete. */
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
EventScriptRecord *esPtr, *prevEsPtr;
for (esPtr = statePtr->scriptRecordPtr, prevEsPtr = NULL; esPtr != NULL;
prevEsPtr = esPtr, esPtr = esPtr->nextPtr) {
if ((esPtr->interp == interp) && (esPtr->mask == mask)) {
if (esPtr == statePtr->scriptRecordPtr) {
statePtr->scriptRecordPtr = esPtr->nextPtr;
} else {
CLANG_ASSERT(prevEsPtr);
prevEsPtr->nextPtr = esPtr->nextPtr;
}
Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr,
TclChannelEventScriptInvoker, esPtr);
TclDecrRefCount(esPtr->scriptPtr);
ckfree(esPtr);
break;
}
}
}
/*
*----------------------------------------------------------------------
*
* CreateScriptRecord --
*
* Creates a record to store a script to be executed when a specific
* event fires on a specific channel.
*
* Results:
* None.
*
* Side effects:
* Causes the script to be stored for later execution.
*
*----------------------------------------------------------------------
*/
static void
CreateScriptRecord(
Tcl_Interp *interp, /* Interpreter in which to execute the stored
* script. */
Channel *chanPtr, /* Channel for which script is to be stored */
int mask, /* Set of events for which script will be
* invoked. */
Tcl_Obj *scriptPtr) /* Pointer to script object. */
{
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
EventScriptRecord *esPtr;
int makeCH;
for (esPtr=statePtr->scriptRecordPtr; esPtr!=NULL; esPtr=esPtr->nextPtr) {
if ((esPtr->interp == interp) && (esPtr->mask == mask)) {
TclDecrRefCount(esPtr->scriptPtr);
esPtr->scriptPtr = NULL;
break;
}
}
makeCH = (esPtr == NULL);
if (makeCH) {
esPtr = (EventScriptRecord *)ckalloc(sizeof(EventScriptRecord));
}
/*
* Initialize the structure before calling Tcl_CreateChannelHandler,
* because a reflected channel calling 'chan postevent' aka
* 'Tcl_NotifyChannel' in its 'watch'Proc will invoke
* 'TclChannelEventScriptInvoker' immediately, and we do not wish it to
* see uninitialized memory and crash. See [Bug 2918110].
*/
esPtr->chanPtr = chanPtr;
esPtr->interp = interp;
esPtr->mask = mask;
Tcl_IncrRefCount(scriptPtr);
esPtr->scriptPtr = scriptPtr;
if (makeCH) {
esPtr->nextPtr = statePtr->scriptRecordPtr;
statePtr->scriptRecordPtr = esPtr;
Tcl_CreateChannelHandler((Tcl_Channel) chanPtr, mask,
TclChannelEventScriptInvoker, esPtr);
}
}
/*
*----------------------------------------------------------------------
*
* TclChannelEventScriptInvoker --
*
* Invokes a script scheduled by "fileevent" for when the channel becomes
* ready for IO. This function is invoked by the channel handler which
* was created by the Tcl "fileevent" command.
*
* Results:
* None.
*
* Side effects:
* Whatever the script does.
*
*----------------------------------------------------------------------
*/
void
TclChannelEventScriptInvoker(
ClientData clientData, /* The script+interp record. */
int mask) /* Not used. */
{
Tcl_Interp *interp; /* Interpreter in which to eval the script. */
Channel *chanPtr; /* The channel for which this handler is
* registered. */
EventScriptRecord *esPtr; /* The event script + interpreter to eval it
* in. */
int result; /* Result of call to eval script. */
esPtr = (EventScriptRecord *)clientData;
chanPtr = esPtr->chanPtr;
mask = esPtr->mask;
interp = esPtr->interp;
/*
* Be sure event executed in managed channel (covering bugs similar [f583715154]).
*/
assert(chanPtr->state->managingThread == Tcl_GetCurrentThread());
/*
* We must preserve the interpreter so we can report errors on it later.
* Note that we do not need to preserve the channel because that is done
* by Tcl_NotifyChannel before calling channel handlers.
*/
Tcl_Preserve(interp);
TclChannelPreserve((Tcl_Channel)chanPtr);
result = Tcl_EvalObjEx(interp, esPtr->scriptPtr, TCL_EVAL_GLOBAL);
/*
* On error, cause a background error and remove the channel handler and
* the script record.
*
* NOTE: Must delete channel handler before causing the background error
* because the background error may want to reinstall the handler.
*/
if (result != TCL_OK) {
if (chanPtr->typePtr != NULL) {
DeleteScriptRecord(interp, chanPtr, mask);
}
Tcl_BackgroundException(interp, result);
}
TclChannelRelease((Tcl_Channel)chanPtr);
Tcl_Release(interp);
}
/*
*----------------------------------------------------------------------
*
* Tcl_FileEventObjCmd --
*
* This procedure implements the "fileevent" Tcl command. See the user
* documentation for details on what it does. This command is based on
* the Tk command "fileevent" which in turn is based on work contributed
* by Mark Diekhans.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* May create a channel handler for the specified channel.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_FileEventObjCmd(
ClientData dummy, /* Not used. */
Tcl_Interp *interp, /* Interpreter in which the channel for which
* to create the handler is found. */
int objc, /* Number of arguments. */
Tcl_Obj *const objv[]) /* Argument objects. */
{
Channel *chanPtr; /* The channel to create the handler for. */
ChannelState *statePtr; /* State info for channel */
Tcl_Channel chan; /* The opaque type for the channel. */
const char *chanName;
int modeIndex; /* Index of mode argument. */
int mask;
static const char *const modeOptions[] = {"readable", "writable", NULL};
static const int maskArray[] = {TCL_READABLE, TCL_WRITABLE};
(void)dummy;
if ((objc != 3) && (objc != 4)) {
Tcl_WrongNumArgs(interp, 1, objv, "channelId event ?script?");
return TCL_ERROR;
}
if (Tcl_GetIndexFromObj(interp, objv[2], modeOptions, "event name", 0,
&modeIndex) != TCL_OK) {
return TCL_ERROR;
}
mask = maskArray[modeIndex];
chanName = TclGetString(objv[1]);
chan = Tcl_GetChannel(interp, chanName, NULL);
if (chan == NULL) {
return TCL_ERROR;
}
chanPtr = (Channel *) chan;
statePtr = chanPtr->state;
if ((statePtr->flags & mask) == 0) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf("channel is not %s",
(mask == TCL_READABLE) ? "readable" : "writable"));
return TCL_ERROR;
}
/*
* If we are supposed to return the script, do so.
*/
if (objc == 3) {
EventScriptRecord *esPtr;
for (esPtr = statePtr->scriptRecordPtr; esPtr != NULL;
esPtr = esPtr->nextPtr) {
if ((esPtr->interp == interp) && (esPtr->mask == mask)) {
Tcl_SetObjResult(interp, esPtr->scriptPtr);
break;
}
}
return TCL_OK;
}
/*
* If we are supposed to delete a stored script, do so.
*/
if (*(TclGetString(objv[3])) == '\0') {
DeleteScriptRecord(interp, chanPtr, mask);
return TCL_OK;
}
/*
* Make the script record that will link between the event and the script
* to invoke. This also creates a channel event handler which will
* evaluate the script in the supplied interpreter.
*/
CreateScriptRecord(interp, chanPtr, mask, objv[3]);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* ZeroTransferTimerProc --
*
* Timer handler scheduled by TclCopyChannel so that -command is
* called asynchronously even when -size is 0.
*
* Results:
* None.
*
* Side effects:
* Calls CopyData for -command invocation.
*
*----------------------------------------------------------------------
*/
static void
ZeroTransferTimerProc(
ClientData clientData)
{
/* calling CopyData with mask==0 still implies immediate invocation of the
* -command callback, and completion of the fcopy.
*/
CopyData((CopyState *)clientData, 0);
}
/*
*----------------------------------------------------------------------
*
* TclCopyChannel --
*
* This routine copies data from one channel to another, either
* synchronously or asynchronously. If a command script is supplied, the
* operation runs in the background. The script is invoked when the copy
* completes. Otherwise the function waits until the copy is completed
* before returning.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* May schedule a background copy operation that causes both channels to
* be marked busy.
*
*----------------------------------------------------------------------
*/
int
TclCopyChannelOld(
Tcl_Interp *interp, /* Current interpreter. */
Tcl_Channel inChan, /* Channel to read from. */
Tcl_Channel outChan, /* Channel to write to. */
int toRead, /* Amount of data to copy, or -1 for all. */
Tcl_Obj *cmdPtr) /* Pointer to script to execute or NULL. */
{
return TclCopyChannel(interp, inChan, outChan, (Tcl_WideInt) toRead,
cmdPtr);
}
int
TclCopyChannel(
Tcl_Interp *interp, /* Current interpreter. */
Tcl_Channel inChan, /* Channel to read from. */
Tcl_Channel outChan, /* Channel to write to. */
Tcl_WideInt toRead, /* Amount of data to copy, or -1 for all. */
Tcl_Obj *cmdPtr) /* Pointer to script to execute or NULL. */
{
Channel *inPtr = (Channel *) inChan;
Channel *outPtr = (Channel *) outChan;
ChannelState *inStatePtr, *outStatePtr;
int readFlags, writeFlags;
CopyState *csPtr;
int nonBlocking = (cmdPtr) ? CHANNEL_NONBLOCKING : 0;
int moveBytes;
inStatePtr = inPtr->state;
outStatePtr = outPtr->state;
if (BUSY_STATE(inStatePtr, TCL_READABLE)) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"channel \"%s\" is busy", Tcl_GetChannelName(inChan)));
}
return TCL_ERROR;
}
if (BUSY_STATE(outStatePtr, TCL_WRITABLE)) {
if (interp) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"channel \"%s\" is busy", Tcl_GetChannelName(outChan)));
}
return TCL_ERROR;
}
readFlags = inStatePtr->flags;
writeFlags = outStatePtr->flags;
/*
* Set up the blocking mode appropriately. Background copies need
* non-blocking channels. Foreground copies need blocking channels. If
* there is an error, restore the old blocking mode.
*/
if (nonBlocking != (readFlags & CHANNEL_NONBLOCKING)) {
if (SetBlockMode(interp, inPtr, nonBlocking ?
TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING) != TCL_OK) {
return TCL_ERROR;
}
}
if ((inPtr!=outPtr) && (nonBlocking!=(writeFlags&CHANNEL_NONBLOCKING)) &&
(SetBlockMode(NULL, outPtr, nonBlocking ?
TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING) != TCL_OK) &&
(nonBlocking != (readFlags & CHANNEL_NONBLOCKING))) {
SetBlockMode(NULL, inPtr, (readFlags & CHANNEL_NONBLOCKING)
? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING);
return TCL_ERROR;
}
/*
* Make sure the output side is unbuffered.
*/
outStatePtr->flags = (outStatePtr->flags & ~CHANNEL_LINEBUFFERED)
| CHANNEL_UNBUFFERED;
/*
* Test for conditions where we know we can just move bytes from input
* channel to output channel with no transformation or even examination
* of the bytes themselves.
*/
moveBytes = inStatePtr->inEofChar == '\0' /* No eofChar to stop input */
&& inStatePtr->inputTranslation == TCL_TRANSLATE_LF
&& outStatePtr->outputTranslation == TCL_TRANSLATE_LF
&& inStatePtr->encoding == outStatePtr->encoding;
/*
* Allocate a new CopyState to maintain info about the current copy in
* progress. This structure will be deallocated when the copy is
* completed.
*/
csPtr = (CopyState *)ckalloc(sizeof(CopyState) + !moveBytes * inStatePtr->bufSize);
csPtr->bufSize = !moveBytes * inStatePtr->bufSize;
csPtr->readPtr = inPtr;
csPtr->writePtr = outPtr;
csPtr->readFlags = readFlags;
csPtr->writeFlags = writeFlags;
csPtr->toRead = toRead;
csPtr->total = (Tcl_WideInt) 0;
csPtr->interp = interp;
if (cmdPtr) {
Tcl_IncrRefCount(cmdPtr);
}
csPtr->cmdPtr = cmdPtr;
inStatePtr->csPtrR = csPtr;
outStatePtr->csPtrW = csPtr;
if (moveBytes) {
return MoveBytes(csPtr);
}
/*
* Special handling of -size 0 async transfers, so that the -command is
* still called asynchronously.
*/
if ((nonBlocking == CHANNEL_NONBLOCKING) && (toRead == 0)) {
Tcl_CreateTimerHandler(0, ZeroTransferTimerProc, csPtr);
return 0;
}
/*
* Start copying data between the channels.
*/
return CopyData(csPtr, 0);
}
/*
*----------------------------------------------------------------------
*
* CopyData --
*
* This function implements the lowest level of the copying mechanism for
* TclCopyChannel.
*
* Results:
* Returns TCL_OK on success, else TCL_ERROR.
*
* Side effects:
* Moves data between channels, may create channel handlers.
*
*----------------------------------------------------------------------
*/
static void
MBCallback(
CopyState *csPtr,
Tcl_Obj *errObj)
{
Tcl_Obj *cmdPtr = Tcl_DuplicateObj(csPtr->cmdPtr);
Tcl_WideInt total = csPtr->total;
Tcl_Interp *interp = csPtr->interp;
int code;
Tcl_IncrRefCount(cmdPtr);
StopCopy(csPtr);
/* TODO: What if cmdPtr is not a list?! */
Tcl_ListObjAppendElement(NULL, cmdPtr, Tcl_NewWideIntObj(total));
if (errObj) {
Tcl_ListObjAppendElement(NULL, cmdPtr, errObj);
}
Tcl_Preserve(interp);
code = Tcl_EvalObjEx(interp, cmdPtr, TCL_EVAL_GLOBAL);
if (code != TCL_OK) {
Tcl_BackgroundException(interp, code);
}
Tcl_Release(interp);
TclDecrRefCount(cmdPtr);
}
static void
MBError(
CopyState *csPtr,
int mask,
int errorCode)
{
Tcl_Channel inChan = (Tcl_Channel) csPtr->readPtr;
Tcl_Channel outChan = (Tcl_Channel) csPtr->writePtr;
Tcl_Obj *errObj;
Tcl_SetErrno(errorCode);
errObj = Tcl_ObjPrintf( "error %sing \"%s\": %s",
(mask & TCL_READABLE) ? "read" : "writ",
Tcl_GetChannelName((mask & TCL_READABLE) ? inChan : outChan),
Tcl_PosixError(csPtr->interp));
if (csPtr->cmdPtr) {
MBCallback(csPtr, errObj);
} else {
Tcl_SetObjResult(csPtr->interp, errObj);
StopCopy(csPtr);
}
}
static void
MBEvent(
ClientData clientData,
int mask)
{
CopyState *csPtr = (CopyState *) clientData;
Tcl_Channel inChan = (Tcl_Channel) csPtr->readPtr;
Tcl_Channel outChan = (Tcl_Channel) csPtr->writePtr;
ChannelState *inStatePtr = csPtr->readPtr->state;
if (mask & TCL_WRITABLE) {
Tcl_DeleteChannelHandler(inChan, MBEvent, csPtr);
Tcl_DeleteChannelHandler(outChan, MBEvent, csPtr);
switch (MBWrite(csPtr)) {
case TCL_OK:
MBCallback(csPtr, NULL);
break;
case TCL_CONTINUE:
Tcl_CreateChannelHandler(inChan, TCL_READABLE, MBEvent, csPtr);
break;
}
} else if (mask & TCL_READABLE) {
if (TCL_OK == MBRead(csPtr)) {
/* When at least one full buffer is present, stop reading. */
if (IsBufferFull(inStatePtr->inQueueHead)
|| !Tcl_InputBlocked(inChan)) {
Tcl_DeleteChannelHandler(inChan, MBEvent, csPtr);
}
/* Successful read -- set up to write the bytes we read */
Tcl_CreateChannelHandler(outChan, TCL_WRITABLE, MBEvent, csPtr);
}
}
}
static int
MBRead(
CopyState *csPtr)
{
ChannelState *inStatePtr = csPtr->readPtr->state;
ChannelBuffer *bufPtr = inStatePtr->inQueueHead;
int code;
if (bufPtr && BytesLeft(bufPtr) > 0) {
return TCL_OK;
}
code = GetInput(inStatePtr->topChanPtr);
if (code == 0 || GotFlag(inStatePtr, CHANNEL_BLOCKED)) {
return TCL_OK;
} else {
MBError(csPtr, TCL_READABLE, code);
return TCL_ERROR;
}
}
static int
MBWrite(
CopyState *csPtr)
{
ChannelState *inStatePtr = csPtr->readPtr->state;
ChannelState *outStatePtr = csPtr->writePtr->state;
ChannelBuffer *bufPtr = inStatePtr->inQueueHead;
ChannelBuffer *tail = NULL;
int code;
Tcl_WideInt inBytes = 0;
/* Count up number of bytes waiting in the input queue */
while (bufPtr) {
inBytes += BytesLeft(bufPtr);
tail = bufPtr;
if (csPtr->toRead != -1 && csPtr->toRead < inBytes) {
/* Queue has enough bytes to complete the copy */
break;
}
bufPtr = bufPtr->nextPtr;
}
if (bufPtr) {
/* Split the overflowing buffer in two */
int extra = (int) (inBytes - csPtr->toRead);
/* Note that going with int for extra assumes that inBytes is not too
* much over toRead to require a wide itself. If that gets violated
* then the calculations involving extra must be made wide too.
*
* Noted with Win32/MSVC debug build treating the warning (possible of
* data in __int64 to int conversion) as error.
*/
bufPtr = AllocChannelBuffer(extra);
tail->nextAdded -= extra;
memcpy(InsertPoint(bufPtr), InsertPoint(tail), extra);
bufPtr->nextAdded += extra;
bufPtr->nextPtr = tail->nextPtr;
tail->nextPtr = NULL;
inBytes = csPtr->toRead;
}
/* Update the byte counts */
if (csPtr->toRead != -1) {
csPtr->toRead -= inBytes;
}
csPtr->total += inBytes;
/* Move buffers from input to output channels */
if (outStatePtr->outQueueTail) {
outStatePtr->outQueueTail->nextPtr = inStatePtr->inQueueHead;
} else {
outStatePtr->outQueueHead = inStatePtr->inQueueHead;
}
outStatePtr->outQueueTail = tail;
inStatePtr->inQueueHead = bufPtr;
if (inStatePtr->inQueueTail == tail) {
inStatePtr->inQueueTail = bufPtr;
}
if (bufPtr == NULL) {
inStatePtr->inQueueTail = NULL;
}
code = FlushChannel(csPtr->interp, outStatePtr->topChanPtr, 0);
if (code) {
MBError(csPtr, TCL_WRITABLE, code);
return TCL_ERROR;
}
if (csPtr->toRead == 0 || GotFlag(inStatePtr, CHANNEL_EOF)) {
return TCL_OK;
}
return TCL_CONTINUE;
}
static int
MoveBytes(
CopyState *csPtr) /* State of copy operation. */
{
ChannelState *outStatePtr = csPtr->writePtr->state;
ChannelBuffer *bufPtr = outStatePtr->curOutPtr;
int errorCode;
if (bufPtr && BytesLeft(bufPtr)) {
/* If we start with unflushed bytes in the destination
* channel, flush them out of the way first. */
errorCode = FlushChannel(csPtr->interp, outStatePtr->topChanPtr, 0);
if (errorCode != 0) {
MBError(csPtr, TCL_WRITABLE, errorCode);
return TCL_ERROR;
}
}
if (csPtr->cmdPtr) {
Tcl_Channel inChan = (Tcl_Channel) csPtr->readPtr;
Tcl_CreateChannelHandler(inChan, TCL_READABLE, MBEvent, csPtr);
return TCL_OK;
}
while (1) {
int code;
if (TCL_ERROR == MBRead(csPtr)) {
return TCL_ERROR;
}
code = MBWrite(csPtr);
if (code == TCL_OK) {
Tcl_SetObjResult(csPtr->interp, Tcl_NewWideIntObj(csPtr->total));
StopCopy(csPtr);
return TCL_OK;
}
if (code == TCL_ERROR) {
return TCL_ERROR;
}
/* code == TCL_CONTINUE --> continue the loop */
}
return TCL_OK; /* Silence compiler warnings */
}
static int
CopyData(
CopyState *csPtr, /* State of copy operation. */
int mask) /* Current channel event flags. */
{
Tcl_Interp *interp;
Tcl_Obj *cmdPtr, *errObj = NULL, *bufObj = NULL, *msg = NULL;
Tcl_Channel inChan, outChan;
ChannelState *inStatePtr, *outStatePtr;
int result = TCL_OK, size, sizeb;
Tcl_WideInt total;
const char *buffer;
int inBinary, outBinary, sameEncoding;
/* Encoding control */
int underflow; /* Input underflow */
inChan = (Tcl_Channel) csPtr->readPtr;
outChan = (Tcl_Channel) csPtr->writePtr;
inStatePtr = csPtr->readPtr->state;
outStatePtr = csPtr->writePtr->state;
interp = csPtr->interp;
cmdPtr = csPtr->cmdPtr;
/*
* Copy the data the slow way, using the translation mechanism.
*
* Note: We have make sure that we use the topmost channel in a stack for
* the copying. The caller uses Tcl_GetChannel to access it, and thus gets
* the bottom of the stack.
*/
inBinary = (inStatePtr->encoding == NULL);
outBinary = (outStatePtr->encoding == NULL);
sameEncoding = (inStatePtr->encoding == outStatePtr->encoding);
if (!(inBinary || sameEncoding)) {
TclNewObj(bufObj);
Tcl_IncrRefCount(bufObj);
}
while (csPtr->toRead != (Tcl_WideInt) 0) {
/*
* Check for unreported background errors.
*/
Tcl_GetChannelError(inChan, &msg);
if ((inStatePtr->unreportedError != 0) || (msg != NULL)) {
Tcl_SetErrno(inStatePtr->unreportedError);
inStatePtr->unreportedError = 0;
goto readError;
}
Tcl_GetChannelError(outChan, &msg);
if ((outStatePtr->unreportedError != 0) || (msg != NULL)) {
Tcl_SetErrno(outStatePtr->unreportedError);
outStatePtr->unreportedError = 0;
goto writeError;
}
if (cmdPtr && (mask == 0)) {
/*
* In async mode, we skip reading synchronously and fake an
* underflow instead to prime the readable fileevent.
*/
size = 0;
underflow = 1;
} else {
/*
* Read up to bufSize bytes.
*/
if ((csPtr->toRead == (Tcl_WideInt) -1)
|| (csPtr->toRead > (Tcl_WideInt) csPtr->bufSize)) {
sizeb = csPtr->bufSize;
} else {
sizeb = (int) csPtr->toRead;
}
if (inBinary || sameEncoding) {
size = DoRead(inStatePtr->topChanPtr, csPtr->buffer, sizeb,
!GotFlag(inStatePtr, CHANNEL_NONBLOCKING));
} else {
size = DoReadChars(inStatePtr->topChanPtr, bufObj, sizeb,
0 /* No append */);
}
underflow = (size >= 0) && (size < sizeb); /* Input underflow */
}
if (size < 0) {
readError:
if (interp) {
TclNewObj(errObj);
Tcl_AppendStringsToObj(errObj, "error reading \"",
Tcl_GetChannelName(inChan), "\": ", NULL);
if (msg != NULL) {
Tcl_AppendObjToObj(errObj, msg);
} else {
Tcl_AppendStringsToObj(errObj, Tcl_PosixError(interp),
NULL);
}
}
if (msg != NULL) {
Tcl_DecrRefCount(msg);
}
break;
} else if (underflow) {
/*
* We had an underflow on the read side. If we are at EOF, and not
* in the synchronous part of an asynchronous fcopy, then the
* copying is done, otherwise set up a channel handler to detect
* when the channel becomes readable again.
*/
if ((size == 0) && Tcl_Eof(inChan) && !(cmdPtr && (mask == 0))) {
break;
}
if (cmdPtr && (!Tcl_Eof(inChan) || (mask == 0)) &&
!(mask & TCL_READABLE)) {
if (mask & TCL_WRITABLE) {
Tcl_DeleteChannelHandler(outChan, CopyEventProc, csPtr);
}
Tcl_CreateChannelHandler(inChan, TCL_READABLE, CopyEventProc,
csPtr);
}
if (size == 0) {
if (!GotFlag(inStatePtr, CHANNEL_NONBLOCKING)) {
/*
* We allowed a short read. Keep trying.
*/
continue;
}
if (bufObj != NULL) {
TclDecrRefCount(bufObj);
bufObj = NULL;
}
return TCL_OK;
}
}
/*
* Now write the buffer out.
*/
if (inBinary || sameEncoding) {
buffer = csPtr->buffer;
sizeb = size;
} else {
buffer = TclGetStringFromObj(bufObj, &sizeb);
}
if (outBinary || sameEncoding) {
sizeb = WriteBytes(outStatePtr->topChanPtr, buffer, sizeb);
} else {
sizeb = WriteChars(outStatePtr->topChanPtr, buffer, sizeb);
}
/*
* [Bug 2895565]. At this point 'size' still contains the number of
* bytes or characters which have been read. We keep this to later to
* update the totals and toRead information, see marker (UP) below. We
* must not overwrite it with 'sizeb', which is the number of written
* bytes or characters, and both EOL translation and encoding
* conversion may have changed this number unpredictably in relation
* to 'size' (It can be smaller or larger, in the latter case able to
* drive toRead below -1, causing infinite looping). Completely
* unsuitable for updating totals and toRead.
*/
if (sizeb < 0) {
writeError:
if (interp) {
TclNewObj(errObj);
Tcl_AppendStringsToObj(errObj, "error writing \"",
Tcl_GetChannelName(outChan), "\": ", NULL);
if (msg != NULL) {
Tcl_AppendObjToObj(errObj, msg);
} else {
Tcl_AppendStringsToObj(errObj, Tcl_PosixError(interp),
NULL);
}
}
if (msg != NULL) {
Tcl_DecrRefCount(msg);
}
break;
}
/*
* Update the current byte count. Do it now so the count is valid
* before a return or break takes us out of the loop. The invariant at
* the top of the loop should be that csPtr->toRead holds the number
* of bytes left to copy.
*/
if (csPtr->toRead != -1) {
csPtr->toRead -= size;
}
csPtr->total += size;
/*
* Break loop if EOF && (size>0)
*/
if (Tcl_Eof(inChan)) {
break;
}
/*
* Check to see if the write is happening in the background. If so,
* stop copying and wait for the channel to become writable again.
* After input underflow we already installed a readable handler
* therefore we don't need a writable handler.
*/
if (!underflow && GotFlag(outStatePtr, BG_FLUSH_SCHEDULED)) {
if (!(mask & TCL_WRITABLE)) {
if (mask & TCL_READABLE) {
Tcl_DeleteChannelHandler(inChan, CopyEventProc, csPtr);
}
Tcl_CreateChannelHandler(outChan, TCL_WRITABLE,
CopyEventProc, csPtr);
}
if (bufObj != NULL) {
TclDecrRefCount(bufObj);
bufObj = NULL;
}
return TCL_OK;
}
/*
* For background copies, we only do one buffer per invocation so we
* don't starve the rest of the system.
*/
if (cmdPtr && (csPtr->toRead != 0)) {
/*
* The first time we enter this code, there won't be a channel
* handler established yet, so do it here.
*/
if (mask == 0) {
Tcl_CreateChannelHandler(outChan, TCL_WRITABLE, CopyEventProc,
csPtr);
}
if (bufObj != NULL) {
TclDecrRefCount(bufObj);
bufObj = NULL;
}
return TCL_OK;
}
} /* while */
if (bufObj != NULL) {
TclDecrRefCount(bufObj);
bufObj = NULL;
}
/*
* Make the callback or return the number of bytes transferred. The local
* total is used because StopCopy frees csPtr.
*/
total = csPtr->total;
if (cmdPtr && interp) {
int code;
/*
* Get a private copy of the command so we can mutate it by adding
* arguments. Note that StopCopy frees our saved reference to the
* original command obj.
*/
cmdPtr = Tcl_DuplicateObj(cmdPtr);
Tcl_IncrRefCount(cmdPtr);
StopCopy(csPtr);
Tcl_Preserve(interp);
Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewWideIntObj(total));
if (errObj) {
Tcl_ListObjAppendElement(interp, cmdPtr, errObj);
}
code = Tcl_EvalObjEx(interp, cmdPtr, TCL_EVAL_GLOBAL);
if (code != TCL_OK) {
Tcl_BackgroundException(interp, code);
result = TCL_ERROR;
}
TclDecrRefCount(cmdPtr);
Tcl_Release(interp);
} else {
StopCopy(csPtr);
if (interp) {
if (errObj) {
Tcl_SetObjResult(interp, errObj);
result = TCL_ERROR;
} else {
Tcl_ResetResult(interp);
Tcl_SetObjResult(interp, Tcl_NewWideIntObj(total));
}
}
}
return result;
}
/*
*----------------------------------------------------------------------
*
* DoRead --
*
* Stores up to "bytesToRead" bytes in memory pointed to by "dst".
* These bytes come from reading the channel "chanPtr" and
* performing the configured translations. No encoding conversions
* are applied to the bytes being read.
*
* Results:
* The number of bytes actually stored (<= bytesToRead),
* or -1 if there is an error in reading the channel. Use
* Tcl_GetErrno() to retrieve the error code for the error
* that occurred.
*
* The number of bytes stored can be less than the number
* requested when
* - EOF is reached on the channel; or
* - the channel is non-blocking, and we've read all we can
* without blocking.
* - a channel reading error occurs (and we return -1)
*
* Side effects:
* May cause input to be buffered.
*
*----------------------------------------------------------------------
*/
static int
DoRead(
Channel *chanPtr, /* The channel from which to read. */
char *dst, /* Where to store input read. */
int bytesToRead, /* Maximum number of bytes to read. */
int allowShortReads) /* Allow half-blocking (pipes,sockets) */
{
ChannelState *statePtr = chanPtr->state;
char *p = dst;
assert(bytesToRead >= 0);
/*
* Early out when we know a read will get the eofchar.
*
* NOTE: This seems to be a bug. The special handling for
* a zero-char read request ought to come first. As coded
* the EOF due to eofchar has distinguishing behavior from
* the EOF due to reported EOF on the underlying device, and
* that seems undesirable. However recent history indicates
* that new inconsistent behavior in a patchlevel has problems
* too. Keep on keeping on for now.
*/
if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) {
SetFlag(statePtr, CHANNEL_EOF);
assert(statePtr->inputEncodingFlags & TCL_ENCODING_END);
assert(!GotFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR));
/* TODO: Don't need this call */
UpdateInterest(chanPtr);
return 0;
}
/*
* Special handling for zero-char read request.
*/
if (bytesToRead == 0) {
if (GotFlag(statePtr, CHANNEL_EOF)) {
statePtr->inputEncodingFlags |= TCL_ENCODING_START;
}
ResetFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_EOF);
statePtr->inputEncodingFlags &= ~TCL_ENCODING_END;
/* TODO: Don't need this call */
UpdateInterest(chanPtr);
return 0;
}
TclChannelPreserve((Tcl_Channel)chanPtr);
while (bytesToRead) {
/*
* Each pass through the loop is intended to process up to one channel
* buffer.
*/
int bytesRead, bytesWritten;
ChannelBuffer *bufPtr = statePtr->inQueueHead;
/*
* Don't read more data if we have what we need.
*/
while (!bufPtr || /* We got no buffer! OR */
(!IsBufferFull(bufPtr) && /* Our buffer has room AND */
(BytesLeft(bufPtr) < bytesToRead))) {
/* Not enough bytes in it yet
* to fill the dst */
int code;
moreData:
code = GetInput(chanPtr);
bufPtr = statePtr->inQueueHead;
assert(bufPtr != NULL);
if (GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED)) {
/*
* Further reads cannot do any more.
*/
break;
}
if (code) {
/*
* Read error
*/
UpdateInterest(chanPtr);
TclChannelRelease((Tcl_Channel)chanPtr);
return -1;
}
assert(IsBufferFull(bufPtr));
}
assert(bufPtr != NULL);
bytesRead = BytesLeft(bufPtr);
bytesWritten = bytesToRead;
TranslateInputEOL(statePtr, p, RemovePoint(bufPtr),
&bytesWritten, &bytesRead);
bufPtr->nextRemoved += bytesRead;
p += bytesWritten;
bytesToRead -= bytesWritten;
if (!IsBufferEmpty(bufPtr)) {
/*
* Buffer is not empty. How can that be?
*
* 0) We stopped early because we got all the bytes we were
* seeking. That's fine.
*/
if (bytesToRead == 0) {
break;
}
/*
* 1) We're @EOF because we saw eof char.
*/
if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) {
break;
}
/*
* 2) The buffer holds a \r while in CRLF translation, followed by
* the end of the buffer.
*/
assert(statePtr->inputTranslation == TCL_TRANSLATE_CRLF);
assert(RemovePoint(bufPtr)[0] == '\r');
assert(BytesLeft(bufPtr) == 1);
if (bufPtr->nextPtr == NULL) {
/*
* There's no more buffered data...
*/
if (statePtr->flags & CHANNEL_EOF) {
/*
* ...and there never will be.
*/
*p++ = '\r';
bytesToRead--;
bufPtr->nextRemoved++;
} else if (statePtr->flags & CHANNEL_BLOCKED) {
/*
* ...and we cannot get more now.
*/
SetFlag(statePtr, CHANNEL_NEED_MORE_DATA);
break;
} else {
/*
* ...so we need to get some.
*/
goto moreData;
}
}
if (bufPtr->nextPtr) {
/*
* There's a next buffer. Shift orphan \r to it.
*/
ChannelBuffer *nextPtr = bufPtr->nextPtr;
nextPtr->nextRemoved -= 1;
RemovePoint(nextPtr)[0] = '\r';
bufPtr->nextRemoved++;
}
}
if (IsBufferEmpty(bufPtr)) {
statePtr->inQueueHead = bufPtr->nextPtr;
if (statePtr->inQueueHead == NULL) {
statePtr->inQueueTail = NULL;
}
RecycleBuffer(statePtr, bufPtr, 0);
bufPtr = statePtr->inQueueHead;
}
if ((GotFlag(statePtr, CHANNEL_NONBLOCKING) || allowShortReads)
&& GotFlag(statePtr, CHANNEL_BLOCKED)) {
break;
}
/*
* When there's no buffered data to read, and we're at EOF, escape to
* the caller.
*/
if (GotFlag(statePtr, CHANNEL_EOF)
&& (bufPtr == NULL || IsBufferEmpty(bufPtr))) {
break;
}
}
if (bytesToRead == 0) {
ResetFlag(statePtr, CHANNEL_BLOCKED);
}
assert(!GotFlag(statePtr, CHANNEL_EOF)
|| GotFlag(statePtr, CHANNEL_STICKY_EOF)
|| Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0);
assert(!(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED)
== (CHANNEL_EOF|CHANNEL_BLOCKED)));
UpdateInterest(chanPtr);
TclChannelRelease((Tcl_Channel)chanPtr);
return (int)(p - dst);
}
/*
*----------------------------------------------------------------------
*
* CopyEventProc --
*
* This routine is invoked as a channel event handler for the background
* copy operation. It is just a trivial wrapper around the CopyData
* routine.
*
* Results:
* None.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static void
CopyEventProc(
ClientData clientData,
int mask)
{
(void) CopyData((CopyState *)clientData, mask);
}
/*
*----------------------------------------------------------------------
*
* StopCopy --
*
* This routine halts a copy that is in progress.
*
* Results:
* None.
*
* Side effects:
* Removes any pending channel handlers and restores the blocking and
* buffering modes of the channels. The CopyState is freed.
*
*----------------------------------------------------------------------
*/
static void
StopCopy(
CopyState *csPtr) /* State for bg copy to stop . */
{
ChannelState *inStatePtr, *outStatePtr;
Tcl_Channel inChan, outChan;
int nonBlocking;
if (!csPtr) {
return;
}
inChan = (Tcl_Channel) csPtr->readPtr;
outChan = (Tcl_Channel) csPtr->writePtr;
inStatePtr = csPtr->readPtr->state;
outStatePtr = csPtr->writePtr->state;
/*
* Restore the old blocking mode and output buffering mode.
*/
nonBlocking = csPtr->readFlags & CHANNEL_NONBLOCKING;
if (nonBlocking != (inStatePtr->flags & CHANNEL_NONBLOCKING)) {
SetBlockMode(NULL, csPtr->readPtr,
nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING);
}
if (csPtr->readPtr != csPtr->writePtr) {
nonBlocking = csPtr->writeFlags & CHANNEL_NONBLOCKING;
if (nonBlocking != (outStatePtr->flags & CHANNEL_NONBLOCKING)) {
SetBlockMode(NULL, csPtr->writePtr,
nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING);
}
}
ResetFlag(outStatePtr, CHANNEL_LINEBUFFERED | CHANNEL_UNBUFFERED);
outStatePtr->flags |=
csPtr->writeFlags & (CHANNEL_LINEBUFFERED | CHANNEL_UNBUFFERED);
if (csPtr->cmdPtr) {
Tcl_DeleteChannelHandler(inChan, CopyEventProc, csPtr);
if (inChan != outChan) {
Tcl_DeleteChannelHandler(outChan, CopyEventProc, csPtr);
}
Tcl_DeleteChannelHandler(inChan, MBEvent, csPtr);
Tcl_DeleteChannelHandler(outChan, MBEvent, csPtr);
TclDecrRefCount(csPtr->cmdPtr);
}
inStatePtr->csPtrR = NULL;
outStatePtr->csPtrW = NULL;
ckfree(csPtr);
}
/*
*----------------------------------------------------------------------
*
* StackSetBlockMode --
*
* This function sets the blocking mode for a channel, iterating through
* each channel in a stack and updates the state flags.
*
* Results:
* 0 if OK, result code from failed blockModeProc otherwise.
*
* Side effects:
* Modifies the blocking mode of the channel and possibly generates an
* error.
*
*----------------------------------------------------------------------
*/
static int
StackSetBlockMode(
Channel *chanPtr, /* Channel to modify. */
int mode) /* One of TCL_MODE_BLOCKING or
* TCL_MODE_NONBLOCKING. */
{
int result = 0;
Tcl_DriverBlockModeProc *blockModeProc;
ChannelState *statePtr = chanPtr->state;
/*
* Start at the top of the channel stack
* TODO: Examine what can go wrong when blockModeProc calls
* disturb the stacking state of the channel.
*/
chanPtr = statePtr->topChanPtr;
while (chanPtr != NULL) {
blockModeProc = Tcl_ChannelBlockModeProc(chanPtr->typePtr);
if (blockModeProc != NULL) {
result = blockModeProc(chanPtr->instanceData, mode);
if (result != 0) {
Tcl_SetErrno(result);
return result;
}
}
chanPtr = chanPtr->downChanPtr;
}
return 0;
}
/*
*----------------------------------------------------------------------
*
* SetBlockMode --
*
* This function sets the blocking mode for a channel and updates the
* state flags.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* Modifies the blocking mode of the channel and possibly generates an
* error.
*
*----------------------------------------------------------------------
*/
static int
SetBlockMode(
Tcl_Interp *interp, /* Interp for error reporting. */
Channel *chanPtr, /* Channel to modify. */
int mode) /* One of TCL_MODE_BLOCKING or
* TCL_MODE_NONBLOCKING. */
{
int result = 0;
ChannelState *statePtr = chanPtr->state;
/* State info for channel */
result = StackSetBlockMode(chanPtr, mode);
if (result != 0) {
if (interp != NULL) {
/*
* TIP #219.
* Move error messages put by the driver into the bypass area and
* put them into the regular interpreter result. Fall back to the
* regular message if nothing was found in the bypass.
*
* Note that we cannot have a message in the interpreter bypass
* area, StackSetBlockMode is restricted to the channel bypass.
* We still need the interp as the destination of the move.
*/
if (!TclChanCaughtErrorBypass(interp, (Tcl_Channel) chanPtr)) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"error setting blocking mode: %s",
Tcl_PosixError(interp)));
}
} else {
/*
* TIP #219.
* If we have no interpreter to put a bypass message into we have
* to clear it, to prevent its propagation and use in other places
* unrelated to the actual occurence of the problem.
*/
Tcl_SetChannelError((Tcl_Channel) chanPtr, NULL);
}
return TCL_ERROR;
}
if (mode == TCL_MODE_BLOCKING) {
ResetFlag(statePtr, CHANNEL_NONBLOCKING | BG_FLUSH_SCHEDULED);
} else {
SetFlag(statePtr, CHANNEL_NONBLOCKING);
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelNames --
*
* Return the names of all open channels in the interp.
*
* Results:
* TCL_OK or TCL_ERROR.
*
* Side effects:
* Interp result modified with list of channel names.
*
*----------------------------------------------------------------------
*/
int
Tcl_GetChannelNames(
Tcl_Interp *interp) /* Interp for error reporting. */
{
return Tcl_GetChannelNamesEx(interp, NULL);
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelNamesEx --
*
* Return the names of open channels in the interp filtered filtered
* through a pattern. If pattern is NULL, it returns all the open
* channels.
*
* Results:
* TCL_OK or TCL_ERROR.
*
* Side effects:
* Interp result modified with list of channel names.
*
*----------------------------------------------------------------------
*/
int
Tcl_GetChannelNamesEx(
Tcl_Interp *interp, /* Interp for error reporting. */
const char *pattern) /* Pattern to filter on. */
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
ChannelState *statePtr;
const char *name; /* Name for channel */
Tcl_Obj *resultPtr; /* Pointer to result object */
Tcl_HashTable *hTblPtr; /* Hash table of channels. */
Tcl_HashEntry *hPtr; /* Search variable. */
Tcl_HashSearch hSearch; /* Search variable. */
if (interp == NULL) {
return TCL_OK;
}
/*
* Get the channel table that stores the channels registered for this
* interpreter.
*/
hTblPtr = GetChannelTable(interp);
TclNewObj(resultPtr);
if ((pattern != NULL) && TclMatchIsTrivial(pattern)
&& !((pattern[0] == 's') && (pattern[1] == 't')
&& (pattern[2] == 'd'))) {
if ((Tcl_FindHashEntry(hTblPtr, pattern) != NULL)
&& (Tcl_ListObjAppendElement(interp, resultPtr,
Tcl_NewStringObj(pattern, -1)) != TCL_OK)) {
goto error;
}
goto done;
}
for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); hPtr != NULL;
hPtr = Tcl_NextHashEntry(&hSearch)) {
statePtr = ((Channel *) Tcl_GetHashValue(hPtr))->state;
if (statePtr->topChanPtr == (Channel *) tsdPtr->stdinChannel) {
name = "stdin";
} else if (statePtr->topChanPtr == (Channel *) tsdPtr->stdoutChannel) {
name = "stdout";
} else if (statePtr->topChanPtr == (Channel *) tsdPtr->stderrChannel) {
name = "stderr";
} else {
/*
* This is also stored in Tcl_GetHashKey(hTblPtr, hPtr), but it's
* simpler to just grab the name from the statePtr.
*/
name = statePtr->channelName;
}
if (((pattern == NULL) || Tcl_StringMatch(name, pattern)) &&
(Tcl_ListObjAppendElement(interp, resultPtr,
Tcl_NewStringObj(name, -1)) != TCL_OK)) {
error:
TclDecrRefCount(resultPtr);
return TCL_ERROR;
}
}
done:
Tcl_SetObjResult(interp, resultPtr);
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_IsChannelRegistered --
*
* Checks whether the channel is associated with the interp. See also
* Tcl_RegisterChannel and Tcl_UnregisterChannel.
*
* Results:
* 0 if the channel is not registered in the interpreter, 1 else.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_IsChannelRegistered(
Tcl_Interp *interp, /* The interp to query of the channel */
Tcl_Channel chan) /* The channel to check */
{
Tcl_HashTable *hTblPtr; /* Hash table of channels. */
Tcl_HashEntry *hPtr; /* Search variable. */
Channel *chanPtr; /* The real IO channel. */
ChannelState *statePtr; /* State of the real channel. */
/*
* Always check bottom-most channel in the stack. This is the one that
* gets registered.
*/
chanPtr = ((Channel *) chan)->state->bottomChanPtr;
statePtr = chanPtr->state;
hTblPtr = (Tcl_HashTable *)Tcl_GetAssocData(interp, "tclIO", NULL);
if (hTblPtr == NULL) {
return 0;
}
hPtr = Tcl_FindHashEntry(hTblPtr, statePtr->channelName);
if (hPtr == NULL) {
return 0;
}
if ((Channel *) Tcl_GetHashValue(hPtr) != chanPtr) {
return 0;
}
return 1;
}
/*
*----------------------------------------------------------------------
*
* Tcl_IsChannelShared --
*
* Checks whether the channel is shared by multiple interpreters.
*
* Results:
* A boolean value (0 = Not shared, 1 = Shared).
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_IsChannelShared(
Tcl_Channel chan) /* The channel to query */
{
ChannelState *statePtr = ((Channel *) chan)->state;
/* State of real channel structure. */
return ((statePtr->refCount > 1) ? 1 : 0);
}
/*
*----------------------------------------------------------------------
*
* Tcl_IsChannelExisting --
*
* Checks whether a channel of the given name exists in the
* (thread)-global list of all channels. See Tcl_GetChannelNamesEx for
* function exposed at the Tcl level.
*
* Results:
* A boolean value (0 = Does not exist, 1 = Does exist).
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_IsChannelExisting(
const char *chanName) /* The name of the channel to look for. */
{
ChannelState *statePtr;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
const char *name;
int chanNameLen;
chanNameLen = strlen(chanName);
for (statePtr = tsdPtr->firstCSPtr; statePtr != NULL;
statePtr = statePtr->nextCSPtr) {
if (statePtr->topChanPtr == (Channel *) tsdPtr->stdinChannel) {
name = "stdin";
} else if (statePtr->topChanPtr == (Channel *) tsdPtr->stdoutChannel) {
name = "stdout";
} else if (statePtr->topChanPtr == (Channel *) tsdPtr->stderrChannel) {
name = "stderr";
} else {
name = statePtr->channelName;
}
if ((*chanName == *name) &&
(memcmp(name, chanName, chanNameLen + 1) == 0)) {
return 1;
}
}
return 0;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelName --
*
* Return the name of the channel type.
*
* Results:
* A pointer the name of the channel type.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
const char *
Tcl_ChannelName(
const Tcl_ChannelType *chanTypePtr) /* Pointer to channel type. */
{
return chanTypePtr->typeName;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelVersion --
*
* Return the of version of the channel type.
*
* Results:
* One of the TCL_CHANNEL_VERSION_* constants from tcl.h
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_ChannelTypeVersion
Tcl_ChannelVersion(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
if ((chanTypePtr->version < TCL_CHANNEL_VERSION_2)
|| (chanTypePtr->version > TCL_CHANNEL_VERSION_5)) {
/*
* In <v2 channel versions, the version field is occupied by the
* Tcl_DriverBlockModeProc
*/
return TCL_CHANNEL_VERSION_1;
}
return chanTypePtr->version;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelBlockModeProc --
*
* Return the Tcl_DriverBlockModeProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------- */
Tcl_DriverBlockModeProc *
Tcl_ChannelBlockModeProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_2) {
/*
* The v1 structure had the blockModeProc in a different place.
*/
return (Tcl_DriverBlockModeProc *) chanTypePtr->version;
}
return chanTypePtr->blockModeProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelCloseProc --
*
* Return the Tcl_DriverCloseProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverCloseProc *
Tcl_ChannelCloseProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->closeProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelClose2Proc --
*
* Return the Tcl_DriverClose2Proc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverClose2Proc *
Tcl_ChannelClose2Proc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->close2Proc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelInputProc --
*
* Return the Tcl_DriverInputProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverInputProc *
Tcl_ChannelInputProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->inputProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelOutputProc --
*
* Return the Tcl_DriverOutputProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverOutputProc *
Tcl_ChannelOutputProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->outputProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelSeekProc --
*
* Return the Tcl_DriverSeekProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverSeekProc *
Tcl_ChannelSeekProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->seekProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelSetOptionProc --
*
* Return the Tcl_DriverSetOptionProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverSetOptionProc *
Tcl_ChannelSetOptionProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->setOptionProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelGetOptionProc --
*
* Return the Tcl_DriverGetOptionProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverGetOptionProc *
Tcl_ChannelGetOptionProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->getOptionProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelWatchProc --
*
* Return the Tcl_DriverWatchProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverWatchProc *
Tcl_ChannelWatchProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->watchProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelGetHandleProc --
*
* Return the Tcl_DriverGetHandleProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverGetHandleProc *
Tcl_ChannelGetHandleProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
return chanTypePtr->getHandleProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelFlushProc --
*
* Return the Tcl_DriverFlushProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverFlushProc *
Tcl_ChannelFlushProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_2) {
return NULL;
}
return chanTypePtr->flushProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelHandlerProc --
*
* Return the Tcl_DriverHandlerProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverHandlerProc *
Tcl_ChannelHandlerProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_2) {
return NULL;
}
return chanTypePtr->handlerProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelWideSeekProc --
*
* Return the Tcl_DriverWideSeekProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverWideSeekProc *
Tcl_ChannelWideSeekProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_3) {
return NULL;
}
return chanTypePtr->wideSeekProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelThreadActionProc --
*
* TIP #218, Channel Thread Actions. Return the
* Tcl_DriverThreadActionProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverThreadActionProc *
Tcl_ChannelThreadActionProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_4) {
return NULL;
}
return chanTypePtr->threadActionProc;
}
/*
*----------------------------------------------------------------------
*
* Tcl_SetChannelErrorInterp --
*
* TIP #219, Tcl Channel Reflection API.
* Store an error message for the I/O system.
*
* Results:
* None.
*
* Side effects:
* Discards a previously stored message.
*
*----------------------------------------------------------------------
*/
void
Tcl_SetChannelErrorInterp(
Tcl_Interp *interp, /* Interp to store the data into. */
Tcl_Obj *msg) /* Error message to store. */
{
Interp *iPtr = (Interp *) interp;
if (iPtr->chanMsg != NULL) {
TclDecrRefCount(iPtr->chanMsg);
iPtr->chanMsg = NULL;
}
if (msg != NULL) {
iPtr->chanMsg = FixLevelCode(msg);
Tcl_IncrRefCount(iPtr->chanMsg);
}
return;
}
/*
*----------------------------------------------------------------------
*
* Tcl_SetChannelError --
*
* TIP #219, Tcl Channel Reflection API.
* Store an error message for the I/O system.
*
* Results:
* None.
*
* Side effects:
* Discards a previously stored message.
*
*----------------------------------------------------------------------
*/
void
Tcl_SetChannelError(
Tcl_Channel chan, /* Channel to store the data into. */
Tcl_Obj *msg) /* Error message to store. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
if (statePtr->chanMsg != NULL) {
TclDecrRefCount(statePtr->chanMsg);
statePtr->chanMsg = NULL;
}
if (msg != NULL) {
statePtr->chanMsg = FixLevelCode(msg);
Tcl_IncrRefCount(statePtr->chanMsg);
}
return;
}
/*
*----------------------------------------------------------------------
*
* FixLevelCode --
*
* TIP #219, Tcl Channel Reflection API.
* Scans an error message for bad -code / -level directives. Returns a
* modified copy with such directives corrected, and the input if it had
* no problems.
*
* Results:
* A Tcl_Obj*
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static Tcl_Obj *
FixLevelCode(
Tcl_Obj *msg)
{
int explicitResult, numOptions, lc, lcn;
Tcl_Obj **lv, **lvn;
int res, i, j, val, lignore, cignore;
int newlevel = -1, newcode = -1;
/* ASSERT msg != NULL */
/*
* Process the caught message.
*
* Syntax = (option value)... ?message?
*
* Bad message syntax causes a panic, because the other side uses
* Tcl_GetReturnOptions and list construction functions to marshall the
* information. Hence an error means that we've got serious breakage.
*/
res = Tcl_ListObjGetElements(NULL, msg, &lc, &lv);
if (res != TCL_OK) {
Tcl_Panic("Tcl_SetChannelError: bad syntax of message");
}
explicitResult = (1 == (lc % 2));
numOptions = lc - explicitResult;
/*
* No options, nothing to do.
*/
if (numOptions == 0) {
return msg;
}
/*
* Check for -code x, x != 1|error, and -level x, x != 0
*/
for (i = 0; i < numOptions; i += 2) {
if (0 == strcmp(TclGetString(lv[i]), "-code")) {
/*
* !"error", !integer, integer != 1 (numeric code for error)
*/
res = TclGetIntFromObj(NULL, lv[i+1], &val);
if (((res == TCL_OK) && (val != 1)) || ((res != TCL_OK) &&
(0 != strcmp(TclGetString(lv[i+1]), "error")))) {
newcode = 1;
}
} else if (0 == strcmp(TclGetString(lv[i]), "-level")) {
/*
* !integer, integer != 0
*/
res = TclGetIntFromObj(NULL, lv [i+1], &val);
if ((res != TCL_OK) || (val != 0)) {
newlevel = 0;
}
}
}
/*
* -code, -level are either not present or ok. Nothing to do.
*/
if ((newlevel < 0) && (newcode < 0)) {
return msg;
}
lcn = numOptions;
if (explicitResult) {
lcn ++;
}
if (newlevel >= 0) {
lcn += 2;
}
if (newcode >= 0) {
lcn += 2;
}
lvn = (Tcl_Obj **)ckalloc(lcn * sizeof(Tcl_Obj *));
/*
* New level/code information is spliced into the first occurence of
* -level, -code, further occurences are ignored. The options cannot be
* not present, we would not come here. Options which are ok are simply
* copied over.
*/
lignore = cignore = 0;
for (i=0, j=0; i<numOptions; i+=2) {
if (0 == strcmp(TclGetString(lv[i]), "-level")) {
if (newlevel >= 0) {
lvn[j++] = lv[i];
lvn[j++] = Tcl_NewIntObj(newlevel);
newlevel = -1;
lignore = 1;
continue;
} else if (lignore) {
continue;
}
} else if (0 == strcmp(TclGetString(lv[i]), "-code")) {
if (newcode >= 0) {
lvn[j++] = lv[i];
lvn[j++] = Tcl_NewIntObj(newcode);
newcode = -1;
cignore = 1;
continue;
} else if (cignore) {
continue;
}
}
/*
* Keep everything else, possibly copied down.
*/
lvn[j++] = lv[i];
lvn[j++] = lv[i+1];
}
if (newlevel >= 0) {
Tcl_Panic("Defined newlevel not used in rewrite");
}
if (newcode >= 0) {
Tcl_Panic("Defined newcode not used in rewrite");
}
if (explicitResult) {
lvn[j++] = lv[i];
}
msg = Tcl_NewListObj(j, lvn);
ckfree(lvn);
return msg;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelErrorInterp --
*
* TIP #219, Tcl Channel Reflection API.
* Return the message stored by the channel driver.
*
* Results:
* Tcl error message object.
*
* Side effects:
* Resets the stored data to NULL.
*
*----------------------------------------------------------------------
*/
void
Tcl_GetChannelErrorInterp(
Tcl_Interp *interp, /* Interp to query. */
Tcl_Obj **msg) /* Place for error message. */
{
Interp *iPtr = (Interp *) interp;
*msg = iPtr->chanMsg;
iPtr->chanMsg = NULL;
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetChannelError --
*
* TIP #219, Tcl Channel Reflection API.
* Return the message stored by the channel driver.
*
* Results:
* Tcl error message object.
*
* Side effects:
* Resets the stored data to NULL.
*
*----------------------------------------------------------------------
*/
void
Tcl_GetChannelError(
Tcl_Channel chan, /* Channel to query. */
Tcl_Obj **msg) /* Place for error message. */
{
ChannelState *statePtr = ((Channel *) chan)->state;
*msg = statePtr->chanMsg;
statePtr->chanMsg = NULL;
}
/*
*----------------------------------------------------------------------
*
* Tcl_ChannelTruncateProc --
*
* TIP #208 (subsection relating to truncation, based on TIP #206).
* Return the Tcl_DriverTruncateProc of the channel type.
*
* Results:
* A pointer to the proc.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_DriverTruncateProc *
Tcl_ChannelTruncateProc(
const Tcl_ChannelType *chanTypePtr)
/* Pointer to channel type. */
{
if (Tcl_ChannelVersion(chanTypePtr) < TCL_CHANNEL_VERSION_5) {
return NULL;
}
return chanTypePtr->truncateProc;
}
/*
*----------------------------------------------------------------------
*
* DupChannelInternalRep --
*
* Initialize the internal representation of a new Tcl_Obj to a copy of
* the internal representation of an existing string object.
*
* Results:
* None.
*
* Side effects:
* copyPtr's internal rep is set to a copy of srcPtr's internal
* representation.
*
*----------------------------------------------------------------------
*/
static void
DupChannelInternalRep(
Tcl_Obj *srcPtr, /* Object with internal rep to copy. Must have
* an internal rep of type "Channel". */
Tcl_Obj *copyPtr) /* Object with internal rep to set. Must not
* currently have an internal rep.*/
{
ResolvedChanName *resPtr = srcPtr->internalRep.twoPtrValue.ptr1;
resPtr->refCount++;
copyPtr->internalRep.twoPtrValue.ptr1 = resPtr;
copyPtr->typePtr = srcPtr->typePtr;
}
/*
*----------------------------------------------------------------------
*
* FreeChannelInternalRep --
*
* Release statePtr storage.
*
* Results:
* None.
*
* Side effects:
* May cause state to be freed.
*
*----------------------------------------------------------------------
*/
static void
FreeChannelInternalRep(
Tcl_Obj *objPtr) /* Object with internal rep to free. */
{
ResolvedChanName *resPtr = objPtr->internalRep.twoPtrValue.ptr1;
objPtr->typePtr = NULL;
if (--resPtr->refCount) {
return;
}
Tcl_Release(resPtr->statePtr);
ckfree(resPtr);
}
#if 0
/*
* For future debugging work, a simple function to print the flags of a
* channel in semi-readable form.
*/
static int
DumpFlags(
char *str,
int flags)
{
char buf[20];
int i = 0;
#define ChanFlag(chr, bit) (buf[i++] = ((flags & (bit)) ? (chr) : '_'))
ChanFlag('r', TCL_READABLE);
ChanFlag('w', TCL_WRITABLE);
ChanFlag('n', CHANNEL_NONBLOCKING);
ChanFlag('l', CHANNEL_LINEBUFFERED);
ChanFlag('u', CHANNEL_UNBUFFERED);
ChanFlag('F', BG_FLUSH_SCHEDULED);
ChanFlag('c', CHANNEL_CLOSED);
ChanFlag('E', CHANNEL_EOF);
ChanFlag('S', CHANNEL_STICKY_EOF);
ChanFlag('B', CHANNEL_BLOCKED);
ChanFlag('/', INPUT_SAW_CR);
ChanFlag('D', CHANNEL_DEAD);
ChanFlag('R', CHANNEL_RAW_MODE);
ChanFlag('x', CHANNEL_INCLOSE);
buf[i] ='\0';
fprintf(stderr, "%s: %s\n", str, buf);
return 0;
}
#endif
/*
* Local Variables:
* mode: c
* c-basic-offset: 4
* fill-column: 78
* tab-width: 8
* indent-tabs-mode: nil
* End:
*/