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

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/*
* tclIORTrans.c --
*
* This file contains the implementation of Tcl's generic transformation
* reflection code, which allows the implementation of Tcl channel
* transformations in Tcl code.
*
* Parts of this file are based on code contributed by Jean-Claude
* Wippler.
*
* See TIP #230 for the specification of this functionality.
*
* Copyright (c) 2007-2008 ActiveState.
*
* 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>
#ifndef EINVAL
#define EINVAL 9
#endif
#ifndef EOK
#define EOK 0
#endif
/*
* Signatures of all functions used in the C layer of the reflection.
*/
static int ReflectClose(ClientData clientData,
Tcl_Interp *interp);
static int ReflectClose2(ClientData clientData,
Tcl_Interp *interp, int flags);
static int ReflectInput(ClientData clientData, char *buf,
int toRead, int *errorCodePtr);
static int ReflectOutput(ClientData clientData, const char *buf,
int toWrite, int *errorCodePtr);
static void ReflectWatch(ClientData clientData, int mask);
static int ReflectBlock(ClientData clientData, int mode);
static Tcl_WideInt ReflectSeekWide(ClientData clientData,
Tcl_WideInt offset, int mode, int *errorCodePtr);
static int ReflectSeek(ClientData clientData, long offset,
int mode, int *errorCodePtr);
static int ReflectGetOption(ClientData clientData,
Tcl_Interp *interp, const char *optionName,
Tcl_DString *dsPtr);
static int ReflectSetOption(ClientData clientData,
Tcl_Interp *interp, const char *optionName,
const char *newValue);
static int ReflectHandle(ClientData clientData, int direction,
ClientData *handle);
static int ReflectNotify(ClientData clientData, int mask);
/*
* The C layer channel type/driver definition used by the reflection.
*/
static const Tcl_ChannelType tclRTransformType = {
"tclrtransform", /* Type name. */
TCL_CHANNEL_VERSION_5, /* v5 channel. */
ReflectClose, /* Close channel, clean instance data. */
ReflectInput, /* Handle read request. */
ReflectOutput, /* Handle write request. */
ReflectSeek, /* Move location of access point. */
ReflectSetOption, /* Set options. */
ReflectGetOption, /* Get options. */
ReflectWatch, /* Initialize notifier. */
ReflectHandle, /* Get OS handle from the channel. */
ReflectClose2, /* No close2 support. NULL'able. */
ReflectBlock, /* Set blocking/nonblocking. */
NULL, /* Flush channel. Not used by core.
* NULL'able. */
ReflectNotify, /* Handle events. */
ReflectSeekWide, /* Move access point (64 bit). */
NULL, /* thread action */
NULL /* truncate */
};
/*
* Structure of the buffer to hold transform results to be consumed by higher
* layers upon reading from the channel, plus the functions to manage such.
*/
typedef struct _ResultBuffer_ {
unsigned char *buf; /* Reference to the buffer area. */
int allocated; /* Allocated size of the buffer area. */
int used; /* Number of bytes in the buffer,
* <= allocated. */
} ResultBuffer;
#define ResultLength(r) ((r)->used)
/* static int ResultLength(ResultBuffer *r); */
static void ResultClear(ResultBuffer *r);
static void ResultInit(ResultBuffer *r);
static void ResultAdd(ResultBuffer *r, unsigned char *buf,
int toWrite);
static int ResultCopy(ResultBuffer *r, unsigned char *buf,
int toRead);
#define RB_INCREMENT (512)
/*
* Convenience macro to make some casts easier to use.
*/
#define UCHARP(x) ((unsigned char *) (x))
/*
* Instance data for a reflected transformation. ===========================
*/
typedef struct {
Tcl_Channel chan; /* Back reference to the channel of the
* transformation itself. */
Tcl_Channel parent; /* Reference to the channel the transformation
* was pushed on. */
Tcl_Interp *interp; /* Reference to the interpreter containing the
* Tcl level part of the channel. */
Tcl_Obj *handle; /* Reference to transform handle. Also stored
* in the argv, see below. The separate field
* gives us direct access, needed when working
* with the reflection maps. */
#ifdef TCL_THREADS
Tcl_ThreadId thread; /* Thread the 'interp' belongs to. */
#endif
Tcl_TimerToken timer;
/* See [==] as well.
* Storage for the command prefix and the additional words required for
* the invocation of methods in the command handler.
*
* argv [0] ... [.] | [argc-2] [argc-1] | [argc] [argc+2]
* cmd ... pfx | method chan | detail1 detail2
* ~~~~ CT ~~~ ~~ CT ~~
*
* CT = Belongs to the 'Command handler Thread'.
*/
int argc; /* Number of preallocated words - 2. */
Tcl_Obj **argv; /* Preallocated array for calling the handler.
* args[0] is placeholder for cmd word.
* Followed by the arguments in the prefix,
* plus 4 placeholders for method, channel,
* and at most two varying (method specific)
* words. */
int methods; /* Bitmask of supported methods. */
/*
* NOTE (9): Should we have predefined shared literals for the method
* names?
*/
int mode; /* Mask of R/W mode */
int nonblocking; /* Flag: Channel is blocking or not. */
int readIsDrained; /* Flag: Read buffers are flushed. */
int eofPending; /* Flag: EOF seen down, but not raised up */
int dead; /* Boolean signal that some operations
* should no longer be attempted. */
ResultBuffer result;
} ReflectedTransform;
/*
* Structure of the table mapping from transform handles to reflected
* transform (channels). Each interpreter which has the handler command for
* one or more reflected transforms records them in such a table, so that we
* are able to find them during interpreter/thread cleanup even if the actual
* channel they belong to was moved to a different interpreter and/or thread.
*
* The table is reachable via the standard interpreter AssocData, the key is
* defined below.
*/
typedef struct {
Tcl_HashTable map;
} ReflectedTransformMap;
#define RTMKEY "ReflectedTransformMap"
/*
* Method literals. ==================================================
*/
static const char *const methodNames[] = {
"clear", /* OPT */
"drain", /* OPT, drain => read */
"finalize", /* */
"flush", /* OPT, flush => write */
"initialize", /* */
"limit?", /* OPT */
"read", /* OPT */
"write", /* OPT */
NULL
};
typedef enum {
METH_CLEAR,
METH_DRAIN,
METH_FINAL,
METH_FLUSH,
METH_INIT,
METH_LIMIT,
METH_READ,
METH_WRITE
} MethodName;
#define FLAG(m) (1 << (m))
#define REQUIRED_METHODS \
(FLAG(METH_INIT) | FLAG(METH_FINAL))
#define RANDW \
(TCL_READABLE | TCL_WRITABLE)
#define IMPLIES(a,b) ((!(a)) || (b))
#define NEGIMPL(a,b)
#define HAS(x,f) (x & FLAG(f))
#ifdef TCL_THREADS
/*
* Thread specific types and structures.
*
* We are here essentially creating a very specific implementation of 'thread
* send'.
*/
/*
* Enumeration of all operations which can be forwarded.
*/
typedef enum {
ForwardedClear,
ForwardedClose,
ForwardedDrain,
ForwardedFlush,
ForwardedInput,
ForwardedLimit,
ForwardedOutput
} ForwardedOperation;
/*
* Event used to forward driver invocations to the thread actually managing
* the channel. We cannot construct the command to execute and forward that.
* Because then it will contain a mixture of Tcl_Obj's belonging to both the
* command handler thread (CT), and the thread managing the channel (MT),
* executed in CT. Tcl_Obj's are not allowed to cross thread boundaries. So we
* forward an operation code, the argument details, and reference to results.
* The command is assembled in the CT and belongs fully to that thread. No
* sharing problems.
*/
typedef struct ForwardParamBase {
int code; /* O: Ok/Fail of the cmd handler */
char *msgStr; /* O: Error message for handler failure */
int mustFree; /* O: True if msgStr is allocated, false if
* otherwise (static). */
} ForwardParamBase;
/*
* Operation specific parameter/result structures. (These are "subtypes" of
* ForwardParamBase. Where an operation does not need any special types, it
* has no "subtype" and just uses ForwardParamBase, as listed above.)
*/
struct ForwardParamTransform {
ForwardParamBase base; /* "Supertype". MUST COME FIRST. */
char *buf; /* I: Bytes to transform,
* O: Bytes in transform result */
int size; /* I: #bytes to transform,
* O: #bytes in the transform result */
};
struct ForwardParamLimit {
ForwardParamBase base; /* "Supertype". MUST COME FIRST. */
int max; /* O: Character read limit */
};
/*
* Now join all these together in a single union for convenience.
*/
typedef union ForwardParam {
ForwardParamBase base;
struct ForwardParamTransform transform;
struct ForwardParamLimit limit;
} ForwardParam;
/*
* Forward declaration.
*/
typedef struct ForwardingResult ForwardingResult;
/*
* General event structure, with reference to operation specific data.
*/
typedef struct ForwardingEvent {
Tcl_Event event; /* Basic event data, has to be first item */
ForwardingResult *resultPtr;
ForwardedOperation op; /* Forwarded driver operation */
ReflectedTransform *rtPtr; /* Channel instance */
ForwardParam *param; /* Packaged arguments and return values, a
* ForwardParam pointer. */
} ForwardingEvent;
/*
* Structure to manage the result of the forwarding. This is not the result of
* the operation itself, but about the success of the forward event itself.
* The event can be successful, even if the operation which was forwarded
* failed. It is also there to manage the synchronization between the involved
* threads.
*/
struct ForwardingResult {
Tcl_ThreadId src; /* Originating thread. */
Tcl_ThreadId dst; /* Thread the op was forwarded to. */
Tcl_Interp *dsti; /* Interpreter in the thread the op was
* forwarded to. */
Tcl_Condition done; /* Condition variable the forwarder blocks
* on. */
int result; /* TCL_OK or TCL_ERROR */
ForwardingEvent *evPtr; /* Event the result belongs to. */
ForwardingResult *prevPtr, *nextPtr;
/* Links into the list of pending forwarded
* results. */
};
typedef struct ThreadSpecificData {
/*
* Table of all reflected transformations owned by this thread.
*/
ReflectedTransformMap *rtmPtr;
} ThreadSpecificData;
static Tcl_ThreadDataKey dataKey;
/*
* List of forwarded operations which have not completed yet, plus the mutex
* to protect the access to this process global list.
*/
static ForwardingResult *forwardList = NULL;
TCL_DECLARE_MUTEX(rtForwardMutex)
/*
* Function containing the generic code executing a forward, and wrapper
* macros for the actual operations we wish to forward. Uses ForwardProc as
* the event function executed by the thread receiving a forwarding event
* (which executes the appropriate function and collects the result, if any).
*
* The two ExitProcs are handlers so that things do not deadlock when either
* thread involved in the forwarding exits. They also clean things up so that
* we don't leak resources when threads go away.
*/
static void ForwardOpToOwnerThread(ReflectedTransform *rtPtr,
ForwardedOperation op, const void *param);
static int ForwardProc(Tcl_Event *evPtr, int mask);
static void SrcExitProc(ClientData clientData);
#define FreeReceivedError(p) \
do { \
if ((p)->base.mustFree) { \
ckfree((p)->base.msgStr); \
} \
} while (0)
#define PassReceivedErrorInterp(i,p) \
do { \
if ((i) != NULL) { \
Tcl_SetChannelErrorInterp((i), \
Tcl_NewStringObj((p)->base.msgStr, -1)); \
} \
FreeReceivedError(p); \
} while (0)
#define PassReceivedError(c,p) \
do { \
Tcl_SetChannelError((c), \
Tcl_NewStringObj((p)->base.msgStr, -1)); \
FreeReceivedError(p); \
} while (0)
#define ForwardSetStaticError(p,emsg) \
do { \
(p)->base.code = TCL_ERROR; \
(p)->base.mustFree = 0; \
(p)->base.msgStr = (char *) (emsg); \
} while (0)
#define ForwardSetDynamicError(p,emsg) \
do { \
(p)->base.code = TCL_ERROR; \
(p)->base.mustFree = 1; \
(p)->base.msgStr = (char *) (emsg); \
} while (0)
static void ForwardSetObjError(ForwardParam *p,
Tcl_Obj *objPtr);
static ReflectedTransformMap * GetThreadReflectedTransformMap(void);
static void DeleteThreadReflectedTransformMap(
ClientData clientData);
#endif /* TCL_THREADS */
#define SetChannelErrorStr(c,msgStr) \
Tcl_SetChannelError((c), Tcl_NewStringObj((msgStr), -1))
static Tcl_Obj * MarshallError(Tcl_Interp *interp);
static void UnmarshallErrorResult(Tcl_Interp *interp,
Tcl_Obj *msgObj);
/*
* Static functions for this file:
*/
static Tcl_Obj * DecodeEventMask(int mask);
static ReflectedTransform * NewReflectedTransform(Tcl_Interp *interp,
Tcl_Obj *cmdpfxObj, int mode, Tcl_Obj *handleObj,
Tcl_Channel parentChan);
static Tcl_Obj * NextHandle(void);
static void FreeReflectedTransform(ReflectedTransform *rtPtr);
static void FreeReflectedTransformArgs(ReflectedTransform *rtPtr);
static int InvokeTclMethod(ReflectedTransform *rtPtr,
const char *method, Tcl_Obj *argOneObj,
Tcl_Obj *argTwoObj, Tcl_Obj **resultObjPtr);
static ReflectedTransformMap * GetReflectedTransformMap(Tcl_Interp *interp);
static void DeleteReflectedTransformMap(ClientData clientData,
Tcl_Interp *interp);
/*
* Global constant strings (messages). ==================
* These string are used directly as bypass errors, thus they have to be valid
* Tcl lists where the last element is the message itself. Hence the
* list-quoting to keep the words of the message together. See also [x].
*/
static const char *msg_read_unsup = "{read not supported by Tcl driver}";
static const char *msg_write_unsup = "{write not supported by Tcl driver}";
#ifdef TCL_THREADS
static const char *msg_send_originlost = "{Channel thread lost}";
static const char *msg_send_dstlost = "{Owner lost}";
#endif /* TCL_THREADS */
static const char *msg_dstlost =
"-code 1 -level 0 -errorcode NONE -errorinfo {} -errorline 1 {Owner lost}";
/*
* Timer management (flushing out buffered data via artificial events).
*/
/*
* Helper functions encapsulating some of the thread forwarding to make the
* control flow in callers easier.
*/
static void TimerKill(ReflectedTransform *rtPtr);
static void TimerSetup(ReflectedTransform *rtPtr);
static void TimerRun(ClientData clientData);
static int TransformRead(ReflectedTransform *rtPtr,
int *errorCodePtr, Tcl_Obj *bufObj);
static int TransformWrite(ReflectedTransform *rtPtr,
int *errorCodePtr, unsigned char *buf,
int toWrite);
static int TransformDrain(ReflectedTransform *rtPtr,
int *errorCodePtr);
static int TransformFlush(ReflectedTransform *rtPtr,
int *errorCodePtr, int op);
static void TransformClear(ReflectedTransform *rtPtr);
static int TransformLimit(ReflectedTransform *rtPtr,
int *errorCodePtr, int *maxPtr);
/*
* Operation codes for TransformFlush().
*/
#define FLUSH_WRITE 1
#define FLUSH_DISCARD 0
/*
* Main methods to plug into the 'chan' ensemble'. ==================
*/
/*
*----------------------------------------------------------------------
*
* TclChanPushObjCmd --
*
* This function is invoked to process the "chan push" Tcl command. See
* the user documentation for details on what it does.
*
* Results:
* A standard Tcl result. The handle of the new channel is placed in the
* interp result.
*
* Side effects:
* Creates a new channel.
*
*----------------------------------------------------------------------
*/
int
TclChanPushObjCmd(
ClientData dummy,
Tcl_Interp *interp,
int objc,
Tcl_Obj *const *objv)
{
ReflectedTransform *rtPtr; /* Instance data of the new (transform)
* channel. */
Tcl_Obj *chanObj; /* Handle of parent channel */
Tcl_Channel parentChan; /* Token of parent channel */
int mode; /* R/W mode of parent, later the new channel.
* Has to match the abilities of the handler
* commands */
Tcl_Obj *cmdObj; /* Command prefix, list of words */
Tcl_Obj *cmdNameObj; /* Command name */
Tcl_Obj *rtId; /* Handle of the new transform (channel) */
Tcl_Obj *modeObj; /* mode in obj form for method call */
int listc; /* Result of 'initialize', and of */
Tcl_Obj **listv; /* its sublist in the 2nd element */
int methIndex; /* Encoded method name */
int result; /* Result code for 'initialize' */
Tcl_Obj *resObj; /* Result data for 'initialize' */
int methods; /* Bitmask for supported methods. */
ReflectedTransformMap *rtmPtr;
/* Map of reflected transforms with handlers
* in this interp. */
Tcl_HashEntry *hPtr; /* Entry in the above map */
int isNew; /* Placeholder. */
(void)dummy;
/*
* Syntax: chan push CHANNEL CMDPREFIX
* [0] [1] [2] [3]
*
* Actually: rPush CHANNEL CMDPREFIX
* [0] [1] [2]
*/
#define CHAN (1)
#define CMD (2)
/*
* Number of arguments...
*/
if (objc != 3) {
Tcl_WrongNumArgs(interp, 1, objv, "channel cmdprefix");
return TCL_ERROR;
}
/*
* First argument is a channel handle.
*/
chanObj = objv[CHAN];
parentChan = Tcl_GetChannel(interp, Tcl_GetString(chanObj), &mode);
if (parentChan == NULL) {
return TCL_ERROR;
}
parentChan = Tcl_GetTopChannel(parentChan);
/*
* Second argument is command prefix, i.e. list of words, first word is
* name of handler command, other words are fixed arguments. Run the
* 'initialize' method to get the list of supported methods. Validate
* this.
*/
cmdObj = objv[CMD];
/*
* Basic check that the command prefix truly is a list.
*/
if (Tcl_ListObjIndex(interp, cmdObj, 0, &cmdNameObj) != TCL_OK) {
return TCL_ERROR;
}
/*
* Now create the transformation (channel).
*/
rtId = NextHandle();
rtPtr = NewReflectedTransform(interp, cmdObj, mode, rtId, parentChan);
/*
* Invoke 'initialize' and validate that the handler is present and ok.
* Squash the transformation if not.
*/
modeObj = DecodeEventMask(mode);
/* assert modeObj.refCount == 1 */
result = InvokeTclMethod(rtPtr, "initialize", modeObj, NULL, &resObj);
Tcl_DecrRefCount(modeObj);
if (result != TCL_OK) {
UnmarshallErrorResult(interp, resObj);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
goto error;
}
/*
* Verify the result.
* - List, of method names. Convert to mask. Check for non-optionals
* through the mask. Compare open mode against optional r/w.
*/
if (Tcl_ListObjGetElements(NULL, resObj, &listc, &listv) != TCL_OK) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"chan handler \"%s initialize\" returned non-list: %s",
Tcl_GetString(cmdObj), Tcl_GetString(resObj)));
Tcl_DecrRefCount(resObj);
goto error;
}
methods = 0;
while (listc > 0) {
if (Tcl_GetIndexFromObj(interp, listv[listc-1], methodNames,
"method", TCL_EXACT, &methIndex) != TCL_OK) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"chan handler \"%s initialize\" returned %s",
Tcl_GetString(cmdObj),
Tcl_GetString(Tcl_GetObjResult(interp))));
Tcl_DecrRefCount(resObj);
goto error;
}
methods |= FLAG(methIndex);
listc--;
}
Tcl_DecrRefCount(resObj);
if ((REQUIRED_METHODS & methods) != REQUIRED_METHODS) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"chan handler \"%s\" does not support all required methods",
Tcl_GetString(cmdObj)));
goto error;
}
/*
* Mode tell us what the parent channel supports. The methods tell us what
* the handler supports. We remove the non-supported bits from the mode
* and check that the channel is not completely inacessible. Afterward the
* mode tells us which methods are still required, and these methods will
* also be supported by the handler, by design of the check.
*/
if (!HAS(methods, METH_READ)) {
mode &= ~TCL_READABLE;
}
if (!HAS(methods, METH_WRITE)) {
mode &= ~TCL_WRITABLE;
}
if (!mode) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"chan handler \"%s\" makes the channel inaccessible",
Tcl_GetString(cmdObj)));
goto error;
}
/*
* The mode and support for it is ok, now check the internal constraints.
*/
if (!IMPLIES(HAS(methods, METH_DRAIN), HAS(methods, METH_READ))) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"chan handler \"%s\" supports \"drain\" but not \"read\"",
Tcl_GetString(cmdObj)));
goto error;
}
if (!IMPLIES(HAS(methods, METH_FLUSH), HAS(methods, METH_WRITE))) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"chan handler \"%s\" supports \"flush\" but not \"write\"",
Tcl_GetString(cmdObj)));
goto error;
}
Tcl_ResetResult(interp);
/*
* Everything is fine now.
*/
rtPtr->methods = methods;
rtPtr->mode = mode;
rtPtr->chan = Tcl_StackChannel(interp, &tclRTransformType, rtPtr, mode,
rtPtr->parent);
/*
* Register the transform in our our map for proper handling of deleted
* interpreters and/or threads.
*/
rtmPtr = GetReflectedTransformMap(interp);
hPtr = Tcl_CreateHashEntry(&rtmPtr->map, Tcl_GetString(rtId), &isNew);
if (!isNew && rtPtr != Tcl_GetHashValue(hPtr)) {
Tcl_Panic("TclChanPushObjCmd: duplicate transformation handle");
}
Tcl_SetHashValue(hPtr, rtPtr);
#ifdef TCL_THREADS
rtmPtr = GetThreadReflectedTransformMap();
hPtr = Tcl_CreateHashEntry(&rtmPtr->map, Tcl_GetString(rtId), &isNew);
Tcl_SetHashValue(hPtr, rtPtr);
#endif /* TCL_THREADS */
/*
* Return the channel as the result of the command.
*/
Tcl_SetObjResult(interp, Tcl_NewStringObj(
Tcl_GetChannelName(rtPtr->chan), -1));
return TCL_OK;
error:
/*
* We are not going through ReflectClose as we never had a channel
* structure.
*/
Tcl_EventuallyFree(rtPtr, (Tcl_FreeProc *) FreeReflectedTransform);
return TCL_ERROR;
#undef CHAN
#undef CMD
}
/*
*----------------------------------------------------------------------
*
* TclChanPopObjCmd --
*
* This function is invoked to process the "chan pop" Tcl command. See
* the user documentation for details on what it does.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* Posts events to a reflected channel, invokes event handlers. The
* latter implies that arbitrary side effects are possible.
*
*----------------------------------------------------------------------
*/
int
TclChanPopObjCmd(
ClientData dummy,
Tcl_Interp *interp,
int objc,
Tcl_Obj *const *objv)
{
/*
* Syntax: chan pop CHANNEL
* [0] [1] [2]
*
* Actually: rPop CHANNEL
* [0] [1]
*/
#define CHAN (1)
const char *chanId; /* Tcl level channel handle */
Tcl_Channel chan; /* Channel associated to the handle */
int mode; /* Channel r/w mode */
(void)dummy;
/*
* Number of arguments...
*/
if (objc != 2) {
Tcl_WrongNumArgs(interp, 1, objv, "channel");
return TCL_ERROR;
}
/*
* First argument is a channel, which may have a (reflected)
* transformation.
*/
chanId = TclGetString(objv[CHAN]);
chan = Tcl_GetChannel(interp, chanId, &mode);
if (chan == NULL) {
return TCL_ERROR;
}
/*
* Removing transformations is generic, and not restricted to reflected
* transformations.
*/
Tcl_UnstackChannel(interp, chan);
return TCL_OK;
#undef CHAN
}
/*
* Channel error message marshalling utilities.
*/
static Tcl_Obj *
MarshallError(
Tcl_Interp *interp)
{
/*
* Capture the result status of the interpreter into a string. => List of
* options and values, followed by the error message. The result has
* refCount 0.
*/
Tcl_Obj *returnOpt = Tcl_GetReturnOptions(interp, TCL_ERROR);
/*
* => returnOpt.refCount == 0. We can append directly.
*/
Tcl_ListObjAppendElement(NULL, returnOpt, Tcl_GetObjResult(interp));
return returnOpt;
}
static void
UnmarshallErrorResult(
Tcl_Interp *interp,
Tcl_Obj *msgObj)
{
int lc;
Tcl_Obj **lv;
int explicitResult;
int numOptions;
/*
* Process the caught message.
*
* Syntax = (option value)... ?message?
*
* Bad syntax causes a panic. This is OK because the other side uses
* Tcl_GetReturnOptions and list construction functions to marshall the
* information; if we panic here, something has gone badly wrong already.
*/
if (Tcl_ListObjGetElements(interp, msgObj, &lc, &lv) != TCL_OK) {
Tcl_Panic("TclChanCaughtErrorBypass: Bad syntax of caught result");
}
if (interp == NULL) {
return;
}
explicitResult = lc & 1; /* Odd number of values? */
numOptions = lc - explicitResult;
if (explicitResult) {
Tcl_SetObjResult(interp, lv[lc-1]);
}
Tcl_SetReturnOptions(interp, Tcl_NewListObj(numOptions, lv));
((Interp *) interp)->flags &= ~ERR_ALREADY_LOGGED;
}
/*
* Driver functions. ================================================
*/
/*
*----------------------------------------------------------------------
*
* ReflectClose --
*
* This function is invoked when the channel is closed, to delete the
* driver specific instance data.
*
* Results:
* A posix error.
*
* Side effects:
* Releases memory. Arbitrary, as it calls upon a script.
*
*----------------------------------------------------------------------
*/
static int
ReflectClose(
ClientData clientData,
Tcl_Interp *interp)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
int errorCode, errorCodeSet = 0;
int result = TCL_OK; /* Result code for 'close' */
Tcl_Obj *resObj; /* Result data for 'close' */
ReflectedTransformMap *rtmPtr;
/* Map of reflected transforms with handlers
* in this interp. */
Tcl_HashEntry *hPtr; /* Entry in the above map */
if (TclInThreadExit()) {
/*
* This call comes from TclFinalizeIOSystem. There are no
* interpreters, and therefore we cannot call upon the handler command
* anymore. Threading is irrelevant as well. We simply clean up all
* our C level data structures and leave the Tcl level to the other
* finalization functions.
*/
/*
* THREADED => Forward this to the origin thread
*
* Note: DeleteThreadReflectedTransformMap() is the thread exit handler
* for the origin thread. Use this to clean up the structure? Except
* if lost?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
ForwardOpToOwnerThread(rtPtr, ForwardedClose, &p);
result = p.base.code;
if (result != TCL_OK) {
FreeReceivedError(&p);
}
}
#endif /* TCL_THREADS */
Tcl_EventuallyFree(rtPtr, (Tcl_FreeProc *) FreeReflectedTransform);
return EOK;
}
/*
* In the reflected channel implementation a cleaned method mask here
* implies that the channel creation was aborted, and "finalize" must not
* be called. for transformations however we are not going through here on
* such an abort, but directly through FreeReflectedTransform. So for us
* that check is not necessary. We always go through 'finalize'.
*/
if (HAS(rtPtr->methods, METH_DRAIN) && !rtPtr->readIsDrained) {
if (!TransformDrain(rtPtr, &errorCode)) {
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
Tcl_EventuallyFree(rtPtr,
(Tcl_FreeProc *) FreeReflectedTransform);
return errorCode;
}
#endif /* TCL_THREADS */
errorCodeSet = 1;
goto cleanup;
}
}
if (HAS(rtPtr->methods, METH_FLUSH)) {
if (!TransformFlush(rtPtr, &errorCode, FLUSH_WRITE)) {
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
Tcl_EventuallyFree(rtPtr,
(Tcl_FreeProc *) FreeReflectedTransform);
return errorCode;
}
#endif /* TCL_THREADS */
errorCodeSet = 1;
goto cleanup;
}
}
/*
* Are we in the correct thread?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
ForwardOpToOwnerThread(rtPtr, ForwardedClose, &p);
result = p.base.code;
Tcl_EventuallyFree(rtPtr, (Tcl_FreeProc *) FreeReflectedTransform);
if (result != TCL_OK) {
PassReceivedErrorInterp(interp, &p);
return EINVAL;
}
return EOK;
}
#endif /* TCL_THREADS */
/*
* Do the actual invokation of "finalize" now; we're in the right thread.
*/
result = InvokeTclMethod(rtPtr, "finalize", NULL, NULL, &resObj);
if ((result != TCL_OK) && (interp != NULL)) {
Tcl_SetChannelErrorInterp(interp, resObj);
}
Tcl_DecrRefCount(resObj); /* Remove reference we held from the
* invoke. */
cleanup:
/*
* Remove the transform from the map before releasing the memory, to
* prevent future accesses from finding and dereferencing a dangling
* pointer.
*
* NOTE: The transform may not be in the map. This is ok, that happens
* when the transform was created in a different interpreter and/or thread
* and then was moved here.
*
* NOTE: The channel may have been removed from the map already via
* the per-interp DeleteReflectedTransformMap exit-handler.
*/
if (!rtPtr->dead) {
rtmPtr = GetReflectedTransformMap(rtPtr->interp);
hPtr = Tcl_FindHashEntry(&rtmPtr->map, Tcl_GetString(rtPtr->handle));
if (hPtr) {
Tcl_DeleteHashEntry(hPtr);
}
/*
* In a threaded interpreter we manage a per-thread map as well,
* to allow us to survive if the script level pulls the rug out
* under a channel by deleting the owning thread.
*/
#ifdef TCL_THREADS
rtmPtr = GetThreadReflectedTransformMap();
hPtr = Tcl_FindHashEntry(&rtmPtr->map, Tcl_GetString(rtPtr->handle));
if (hPtr) {
Tcl_DeleteHashEntry(hPtr);
}
#endif /* TCL_THREADS */
}
Tcl_EventuallyFree (rtPtr, (Tcl_FreeProc *) FreeReflectedTransform);
return errorCodeSet ? errorCode : ((result == TCL_OK) ? EOK : EINVAL);
}
static int
ReflectClose2(
ClientData clientData,
Tcl_Interp *interp,
int flags)
{
if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) == 0) {
return ReflectClose(clientData, interp);
}
return EINVAL;
}
/*
*----------------------------------------------------------------------
*
* ReflectInput --
*
* This function is invoked when more data is requested from the channel.
*
* Results:
* The number of bytes read.
*
* Side effects:
* Allocates memory. Arbitrary, as it calls upon a script.
*
*----------------------------------------------------------------------
*/
static int
ReflectInput(
ClientData clientData,
char *buf,
int toRead,
int *errorCodePtr)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
int gotBytes, copied, readBytes;
Tcl_Obj *bufObj;
/*
* The following check can be done before thread redirection, because we
* are reading from an item which is readonly, i.e. will never change
* during the lifetime of the channel.
*/
if (!(rtPtr->methods & FLAG(METH_READ))) {
SetChannelErrorStr(rtPtr->chan, msg_read_unsup);
*errorCodePtr = EINVAL;
return -1;
}
Tcl_Preserve(rtPtr);
/* TODO: Consider a more appropriate buffer size. */
bufObj = Tcl_NewByteArrayObj(NULL, toRead);
Tcl_IncrRefCount(bufObj);
gotBytes = 0;
if (rtPtr->eofPending) {
goto stop;
}
rtPtr->readIsDrained = 0;
while (toRead > 0) {
/*
* Loop until the request is satisfied (or no data available from
* below, possibly EOF).
*/
copied = ResultCopy(&rtPtr->result, UCHARP(buf), toRead);
toRead -= copied;
buf += copied;
gotBytes += copied;
if (toRead == 0) {
goto stop;
}
if (rtPtr->eofPending) {
goto stop;
}
/*
* The buffer is exhausted, but the caller wants even more. We now
* have to go to the underlying channel, get more bytes and then
* transform them for delivery. We may not get what we want (full EOF
* or temporarily out of data).
*
* Length (rtPtr->result) == 0, toRead > 0 here. Use 'buf'! as target
* to store the intermediary information read from the parent channel.
*
* Ask the transform how much data it allows us to read from the
* underlying channel. This feature allows the transform to signal EOF
* upstream although there is none downstream. Useful to control an
* unbounded 'fcopy' for example, either through counting bytes, or by
* pattern matching.
*/
if ((rtPtr->methods & FLAG(METH_LIMIT))) {
int maxRead = -1;
if (!TransformLimit(rtPtr, errorCodePtr, &maxRead)) {
goto error;
}
if (maxRead == 0) {
goto stop;
} else if (maxRead > 0) {
if (maxRead < toRead) {
toRead = maxRead;
}
} /* else: 'maxRead < 0' == Accept the current value of toRead */
}
if (toRead <= 0) {
goto stop;
}
readBytes = Tcl_ReadRaw(rtPtr->parent,
(char *) Tcl_SetByteArrayLength(bufObj, toRead), toRead);
if (readBytes < 0) {
if (Tcl_InputBlocked(rtPtr->parent) && (gotBytes > 0)) {
/*
* Down channel is blocked and offers zero additional bytes.
* The nonzero gotBytes already returned makes the total
* operation a valid short read. Return to caller.
*/
goto stop;
}
/*
* Either the down channel is not blocked (a real error)
* or it is and there are gotBytes==0 byte copied so far.
* In either case, pass up the error, so we either report
* any real error, or do not mistakenly signal EOF by
* returning 0 to the caller.
*/
*errorCodePtr = Tcl_GetErrno();
goto error;
}
if (readBytes == 0) {
/*
* Zero returned from Tcl_ReadRaw() always indicates EOF
* on the down channel.
*/
rtPtr->eofPending = 1;
/*
* Now this is a bit different. The partial data waiting is
* converted and returned.
*/
if (HAS(rtPtr->methods, METH_DRAIN)) {
if (!TransformDrain(rtPtr, errorCodePtr)) {
goto error;
}
}
if (ResultLength(&rtPtr->result) == 0) {
/*
* The drain delivered nothing.
*/
goto stop;
}
continue; /* at: while (toRead > 0) */
} /* readBytes == 0 */
/*
* Transform the read chunk, which was not empty. Anything we got back
* is a transformation result is put into our buffers, and the next
* iteration will put it into the result.
*/
Tcl_SetByteArrayLength(bufObj, readBytes);
if (!TransformRead(rtPtr, errorCodePtr, bufObj)) {
goto error;
}
if (Tcl_IsShared(bufObj)) {
Tcl_DecrRefCount(bufObj);
bufObj = Tcl_NewObj();
Tcl_IncrRefCount(bufObj);
}
Tcl_SetByteArrayLength(bufObj, 0);
} /* while toRead > 0 */
stop:
if (gotBytes == 0) {
rtPtr->eofPending = 0;
}
Tcl_DecrRefCount(bufObj);
Tcl_Release(rtPtr);
return gotBytes;
error:
gotBytes = -1;
goto stop;
}
/*
*----------------------------------------------------------------------
*
* ReflectOutput --
*
* This function is invoked when data is written to the channel.
*
* Results:
* The number of bytes actually written.
*
* Side effects:
* Allocates memory. Arbitrary, as it calls upon a script.
*
*----------------------------------------------------------------------
*/
static int
ReflectOutput(
ClientData clientData,
const char *buf,
int toWrite,
int *errorCodePtr)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
/*
* The following check can be done before thread redirection, because we
* are reading from an item which is readonly, i.e. will never change
* during the lifetime of the channel.
*/
if (!(rtPtr->methods & FLAG(METH_WRITE))) {
SetChannelErrorStr(rtPtr->chan, msg_write_unsup);
*errorCodePtr = EINVAL;
return -1;
}
if (toWrite == 0) {
/*
* Nothing came in to write, ignore the call
*/
return 0;
}
/*
* Discard partial data in the input buffers, i.e. on the read side. Like
* we do when explicitly seeking as well.
*/
Tcl_Preserve(rtPtr);
if ((rtPtr->methods & FLAG(METH_CLEAR))) {
TransformClear(rtPtr);
}
/*
* Hand the data to the transformation itself. Anything it deigned to
* return to us is a (partial) transformation result and written to the
* parent channel for further processing.
*/
if (!TransformWrite(rtPtr, errorCodePtr, UCHARP(buf), toWrite)) {
Tcl_Release(rtPtr);
return -1;
}
*errorCodePtr = EOK;
Tcl_Release(rtPtr);
return toWrite;
}
/*
*----------------------------------------------------------------------
*
* ReflectSeekWide / ReflectSeek --
*
* This function is invoked when the user wishes to seek on the channel.
*
* Results:
* The new location of the access point.
*
* Side effects:
* Allocates memory. Arbitrary, per the parent channel, and the called
* scripts.
*
*----------------------------------------------------------------------
*/
static Tcl_WideInt
ReflectSeekWide(
ClientData clientData,
Tcl_WideInt offset,
int seekMode,
int *errorCodePtr)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
Channel *parent = (Channel *) rtPtr->parent;
Tcl_WideInt curPos; /* Position on the device. */
Tcl_DriverSeekProc *seekProc =
Tcl_ChannelSeekProc(Tcl_GetChannelType(rtPtr->parent));
/*
* Fail if the parent channel is not seekable.
*/
if (seekProc == NULL) {
Tcl_SetErrno(EINVAL);
return Tcl_LongAsWide(-1);
}
/*
* Check if we can leave out involving the Tcl level, i.e. transformation
* handler. This is true for tell requests, and transformations which
* support neither flush, nor drain. For these cases we can pass the
* request down and the result back up unchanged.
*/
Tcl_Preserve(rtPtr);
if (((seekMode != SEEK_CUR) || (offset != 0))
&& (HAS(rtPtr->methods, METH_CLEAR)
|| HAS(rtPtr->methods, METH_FLUSH))) {
/*
* Neither a tell request, nor clear/flush both not supported. We have
* to go through the Tcl level to clear and/or flush the
* transformation.
*/
if (rtPtr->methods & FLAG(METH_CLEAR)) {
TransformClear(rtPtr);
}
/*
* When flushing the transform for seeking the generated results are
* irrelevant. We cannot put them into the channel, this would move
* the location, throwing it off with regard to where we are and are
* seeking to.
*/
if (HAS(rtPtr->methods, METH_FLUSH)) {
if (!TransformFlush(rtPtr, errorCodePtr, FLUSH_DISCARD)) {
Tcl_Release(rtPtr);
return -1;
}
}
}
/*
* Now seek to the new position in the channel as requested by the
* caller. Note that we prefer the wideSeekProc if that is available and
* non-NULL...
*/
if (Tcl_ChannelWideSeekProc(parent->typePtr) != NULL) {
curPos = Tcl_ChannelWideSeekProc(parent->typePtr)(parent->instanceData, offset,
seekMode, errorCodePtr);
} else if (offset < Tcl_LongAsWide(LONG_MIN) ||
offset > Tcl_LongAsWide(LONG_MAX)) {
*errorCodePtr = EOVERFLOW;
curPos = Tcl_LongAsWide(-1);
} else {
curPos = Tcl_LongAsWide(Tcl_ChannelSeekProc(parent->typePtr)(
parent->instanceData, Tcl_WideAsLong(offset), seekMode,
errorCodePtr));
}
if (curPos == -1) {
Tcl_SetErrno(*errorCodePtr);
}
*errorCodePtr = EOK;
Tcl_Release(rtPtr);
return curPos;
}
static int
ReflectSeek(
ClientData clientData,
long offset,
int seekMode,
int *errorCodePtr)
{
/*
* This function can be invoked from a transformation which is based on
* standard seeking, i.e. non-wide. Because of this we have to implement
* it, a dummy is not enough. We simply delegate the call to the wide
* routine.
*/
return (int) ReflectSeekWide(clientData, Tcl_LongAsWide(offset), seekMode,
errorCodePtr);
}
/*
*----------------------------------------------------------------------
*
* ReflectWatch --
*
* This function is invoked to tell the channel what events the I/O
* system is interested in.
*
* Results:
* None.
*
* Side effects:
* Allocates memory. Arbitrary, as it calls upon a script.
*
*----------------------------------------------------------------------
*/
static void
ReflectWatch(
ClientData clientData,
int mask)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
Tcl_DriverWatchProc *watchProc;
watchProc = Tcl_ChannelWatchProc(Tcl_GetChannelType(rtPtr->parent));
watchProc(Tcl_GetChannelInstanceData(rtPtr->parent), mask);
/*
* Management of the internal timer.
*/
if (!(mask & TCL_READABLE) || (ResultLength(&rtPtr->result) == 0)) {
/*
* A pending timer may exist, but either is there no (more) interest
* in the events it generates or nothing is available for reading.
* Remove it, if existing.
*/
TimerKill(rtPtr);
} else {
/*
* There might be no pending timer, but there is interest in readable
* events and we actually have data waiting, so generate a timer to
* flush that if it does not exist.
*/
TimerSetup(rtPtr);
}
}
/*
*----------------------------------------------------------------------
*
* ReflectBlock --
*
* This function is invoked to tell the channel which blocking behaviour
* is required of it.
*
* Results:
* A posix error number.
*
* Side effects:
* Allocates memory. Arbitrary, as it calls upon a script.
*
*----------------------------------------------------------------------
*/
static int
ReflectBlock(
ClientData clientData,
int nonblocking)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
/*
* Transformations simply record the blocking mode in their C level
* structure for use by --> ReflectInput. The Tcl level doesn't see this
* information or change. As such thread forwarding is not required.
*/
rtPtr->nonblocking = nonblocking;
return EOK;
}
/*
*----------------------------------------------------------------------
*
* ReflectSetOption --
*
* This function is invoked to configure a channel option.
*
* Results:
* A standard Tcl result code.
*
* Side effects:
* Arbitrary, per the parent channel.
*
*----------------------------------------------------------------------
*/
static int
ReflectSetOption(
ClientData clientData, /* Channel to query */
Tcl_Interp *interp, /* Interpreter to leave error messages in */
const char *optionName, /* Name of requested option */
const char *newValue) /* The new value */
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
/*
* Transformations have no options. Thus the call is passed down unchanged
* to the parent channel for processing. Its results are passed back
* unchanged as well. This all happens in the thread we are in. As the Tcl
* level is not involved there is no need for thread forwarding.
*/
Tcl_DriverSetOptionProc *setOptionProc =
Tcl_ChannelSetOptionProc(Tcl_GetChannelType(rtPtr->parent));
if (setOptionProc == NULL) {
return TCL_ERROR;
}
return setOptionProc(Tcl_GetChannelInstanceData(rtPtr->parent), interp,
optionName, newValue);
}
/*
*----------------------------------------------------------------------
*
* ReflectGetOption --
*
* This function is invoked to retrieve all or a channel options.
*
* Results:
* A standard Tcl result code.
*
* Side effects:
* Arbitrary, per the parent channel.
*
*----------------------------------------------------------------------
*/
static int
ReflectGetOption(
ClientData clientData, /* Channel to query */
Tcl_Interp *interp, /* Interpreter to leave error messages in */
const char *optionName, /* Name of reuqested option */
Tcl_DString *dsPtr) /* String to place the result into */
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
/*
* Transformations have no options. Thus the call is passed down unchanged
* to the parent channel for processing. Its results are passed back
* unchanged as well. This all happens in the thread we are in. As the Tcl
* level is not involved there is no need for thread forwarding.
*
* Note that the parent not having a driver for option retrieval is not an
* immediate error. A query for all options is ok. Only a request for a
* specific option has to fail.
*/
Tcl_DriverGetOptionProc *getOptionProc =
Tcl_ChannelGetOptionProc(Tcl_GetChannelType(rtPtr->parent));
if (getOptionProc != NULL) {
return getOptionProc(Tcl_GetChannelInstanceData(rtPtr->parent),
interp, optionName, dsPtr);
} else if (optionName == NULL) {
return TCL_OK;
} else {
return TCL_ERROR;
}
}
/*
*----------------------------------------------------------------------
*
* ReflectHandle --
*
* This function is invoked to retrieve the associated file handle.
*
* Results:
* A standard Tcl result code.
*
* Side effects:
* Arbitrary, per the parent channel.
*
*----------------------------------------------------------------------
*/
static int
ReflectHandle(
ClientData clientData,
int direction,
ClientData *handlePtr)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
/*
* Transformations have no handle of their own. As such we simply query
* the parent channel for it. This way the qery will ripple down through
* all transformations until reaches the base channel. Which then returns
* its handle, or fails. The former will then ripple up the stack.
*
* This all happens in the thread we are in. As the Tcl level is not
* involved no forwarding is required.
*/
return Tcl_GetChannelHandle(rtPtr->parent, direction, handlePtr);
}
/*
*----------------------------------------------------------------------
*
* ReflectNotify --
*
* This function is invoked to reported incoming events.
*
* Results:
* A standard Tcl result code.
*
* Side effects:
* Arbitrary, per the parent channel.
*
*----------------------------------------------------------------------
*/
static int
ReflectNotify(
ClientData clientData,
int mask)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
/*
* An event occured in the underlying channel.
*
* We delete our timer. It was not fired, yet we are here, so the channel
* below generated such an event and we don't have to. The renewal of the
* interest after the execution of channel handlers will eventually cause
* us to recreate the timer (in ReflectWatch).
*/
TimerKill(rtPtr);
/*
* Pass to higher layers.
*/
return mask;
}
/*
* Helpers. =========================================================
*/
/*
*----------------------------------------------------------------------
*
* DecodeEventMask --
*
* This function takes an internal bitmask of events and constructs the
* equivalent list of event items.
*
* Results:
* A Tcl_Obj reference. The object will have a refCount of one. The user
* has to decrement it to release the object.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
* DUPLICATE of 'DecodeEventMask' in tclIORChan.c
*/
static Tcl_Obj *
DecodeEventMask(
int mask)
{
const char *eventStr;
Tcl_Obj *evObj;
switch (mask & RANDW) {
case RANDW:
eventStr = "read write";
break;
case TCL_READABLE:
eventStr = "read";
break;
case TCL_WRITABLE:
eventStr = "write";
break;
default:
eventStr = "";
break;
}
evObj = Tcl_NewStringObj(eventStr, -1);
Tcl_IncrRefCount(evObj);
return evObj;
}
/*
*----------------------------------------------------------------------
*
* NewReflectedTransform --
*
* This function is invoked to allocate and initialize the instance data
* of a new reflected channel.
*
* Results:
* A heap-allocated channel instance.
*
* Side effects:
* Allocates memory.
*
*----------------------------------------------------------------------
*/
static ReflectedTransform *
NewReflectedTransform(
Tcl_Interp *interp,
Tcl_Obj *cmdpfxObj,
int mode,
Tcl_Obj *handleObj,
Tcl_Channel parentChan)
{
ReflectedTransform *rtPtr;
int listc;
Tcl_Obj **listv;
int i;
(void)mode;
rtPtr = (ReflectedTransform *)ckalloc(sizeof(ReflectedTransform));
/* rtPtr->chan: Assigned by caller. Dummy data here. */
/* rtPtr->methods: Assigned by caller. Dummy data here. */
rtPtr->chan = NULL;
rtPtr->methods = 0;
#ifdef TCL_THREADS
rtPtr->thread = Tcl_GetCurrentThread();
#endif
rtPtr->parent = parentChan;
rtPtr->interp = interp;
rtPtr->handle = handleObj;
Tcl_IncrRefCount(handleObj);
rtPtr->timer = NULL;
rtPtr->mode = 0;
rtPtr->readIsDrained = 0;
rtPtr->eofPending = 0;
rtPtr->nonblocking =
(((Channel *) parentChan)->state->flags & CHANNEL_NONBLOCKING);
rtPtr->dead = 0;
/*
* Query parent for current blocking mode.
*/
ResultInit(&rtPtr->result);
/*
* Method placeholder.
*/
/* ASSERT: cmdpfxObj is a Tcl List */
Tcl_ListObjGetElements(interp, cmdpfxObj, &listc, &listv);
/*
* See [==] as well.
* Storage for the command prefix and the additional words required for
* the invocation of methods in the command handler.
*
* listv [0] [listc-1] | [listc] [listc+1] |
* argv [0] ... [.] | [argc-2] [argc-1] | [argc] [argc+2]
* cmd ... pfx | method chan | detail1 detail2
*/
rtPtr->argc = listc + 2;
rtPtr->argv = (Tcl_Obj **)ckalloc(sizeof(Tcl_Obj *) * (listc+4));
/*
* Duplicate object references.
*/
for (i=0; i<listc ; i++) {
Tcl_Obj *word = rtPtr->argv[i] = listv[i];
Tcl_IncrRefCount(word);
}
i++; /* Skip placeholder for method */
/*
* See [x] in FreeReflectedTransform for release
*/
rtPtr->argv[i] = handleObj;
Tcl_IncrRefCount(handleObj);
/*
* The next two objects are kept empty, varying arguments.
*/
/*
* Initialization complete.
*/
return rtPtr;
}
/*
*----------------------------------------------------------------------
*
* NextHandle --
*
* This function is invoked to generate a channel handle for a new
* reflected channel.
*
* Results:
* A Tcl_Obj containing the string of the new channel handle. The
* refcount of the returned object is -- zero --.
*
* Side effects:
* May allocate memory. Mutex protected critical section locks out other
* threads for a short time.
*
*----------------------------------------------------------------------
*/
static Tcl_Obj *
NextHandle(void)
{
/*
* Count number of generated reflected channels. Used for id generation.
* Ids are never reclaimed and there is no dealing with wrap around. On
* the other hand, "unsigned long" should be big enough except for
* absolute longrunners (generate a 100 ids per second => overflow will
* occur in 1 1/3 years).
*/
TCL_DECLARE_MUTEX(rtCounterMutex)
static unsigned long rtCounter = 0;
Tcl_Obj *resObj;
Tcl_MutexLock(&rtCounterMutex);
resObj = Tcl_ObjPrintf("rt%lu", rtCounter);
rtCounter++;
Tcl_MutexUnlock(&rtCounterMutex);
return resObj;
}
static void
FreeReflectedTransformArgs(
ReflectedTransform *rtPtr)
{
int i, n = rtPtr->argc - 2;
if (n < 0) {
return;
}
Tcl_DecrRefCount(rtPtr->handle);
rtPtr->handle = NULL;
for (i=0; i<n; i++) {
Tcl_DecrRefCount(rtPtr->argv[i]);
}
/*
* See [x] in NewReflectedTransform for lock
* n+1 = argc-1.
*/
Tcl_DecrRefCount(rtPtr->argv[n+1]);
rtPtr->argc = 1;
}
static void
FreeReflectedTransform(
ReflectedTransform *rtPtr)
{
TimerKill(rtPtr);
ResultClear(&rtPtr->result);
FreeReflectedTransformArgs(rtPtr);
ckfree(rtPtr->argv);
ckfree(rtPtr);
}
/*
*----------------------------------------------------------------------
*
* InvokeTclMethod --
*
* This function is used to invoke the Tcl level of a reflected channel.
* It handles all the command assembly, invokation, and generic state and
* result mgmt. It does *not* handle thread redirection; that is the
* responsibility of clients of this function.
*
* Results:
* Result code and data as returned by the method.
*
* Side effects:
* Arbitrary, as it calls upon a Tcl script.
*
* Contract:
* argOneObj.refCount >= 1 on entry and exit, if argOneObj != NULL
* argTwoObj.refCount >= 1 on entry and exit, if argTwoObj != NULL
* resObj.refCount in {0, 1, ...}
*
*----------------------------------------------------------------------
* Semi-DUPLICATE of 'InvokeTclMethod' in tclIORChan.c
* - Semi because different structures are used.
* - Still possible to factor out the commonalities into a separate structure.
*/
static int
InvokeTclMethod(
ReflectedTransform *rtPtr,
const char *method,
Tcl_Obj *argOneObj, /* NULL'able */
Tcl_Obj *argTwoObj, /* NULL'able */
Tcl_Obj **resultObjPtr) /* NULL'able */
{
int cmdc; /* #words in constructed command */
Tcl_Obj *methObj = NULL; /* Method name in object form */
Tcl_InterpState sr; /* State of handler interp */
int result; /* Result code of method invokation */
Tcl_Obj *resObj = NULL; /* Result of method invokation. */
if (rtPtr->dead) {
/*
* The transform is marked as dead. Bail out immediately, with an
* appropriate error.
*/
if (resultObjPtr != NULL) {
resObj = Tcl_NewStringObj(msg_dstlost,-1);
*resultObjPtr = resObj;
Tcl_IncrRefCount(resObj);
}
return TCL_ERROR;
}
/*
* NOTE (5): Decide impl. issue: Cache objects with method names?
* Requires TSD data as reflections can be created in many different
* threads.
* NO: Caching of command resolutions means storage per channel.
*/
/*
* Insert method into the pre-allocated area, after the command prefix,
* before the channel id.
*/
methObj = Tcl_NewStringObj(method, -1);
Tcl_IncrRefCount(methObj);
rtPtr->argv[rtPtr->argc - 2] = methObj;
/*
* Append the additional argument containing method specific details
* behind the channel id. If specified.
*
* Because of the contract there is no need to increment the refcounts.
* The objects will survive the Tcl_EvalObjv without change.
*/
cmdc = rtPtr->argc;
if (argOneObj) {
rtPtr->argv[cmdc] = argOneObj;
cmdc++;
if (argTwoObj) {
rtPtr->argv[cmdc] = argTwoObj;
cmdc++;
}
}
/*
* And run the handler... This is done in auch a manner which leaves any
* existing state intact.
*/
sr = Tcl_SaveInterpState(rtPtr->interp, 0 /* Dummy */);
Tcl_Preserve(rtPtr);
Tcl_Preserve(rtPtr->interp);
result = Tcl_EvalObjv(rtPtr->interp, cmdc, rtPtr->argv, TCL_EVAL_GLOBAL);
/*
* We do not try to extract the result information if the caller has no
* interest in it. I.e. there is no need to put effort into creating
* something which is discarded immediately after.
*/
if (resultObjPtr) {
if (result == TCL_OK) {
/*
* Ok result taken as is, also if the caller requests that there
* is no capture.
*/
resObj = Tcl_GetObjResult(rtPtr->interp);
} else {
/*
* Non-ok result is always treated as an error. We have to capture
* the full state of the result, including additional options.
*
* This is complex and ugly, and would be completely unnecessary
* if we only added support for a TCL_FORBID_EXCEPTIONS flag.
*/
if (result != TCL_ERROR) {
Tcl_Obj *cmd = Tcl_NewListObj(cmdc, rtPtr->argv);
int cmdLen;
const char *cmdString = Tcl_GetStringFromObj(cmd, &cmdLen);
Tcl_IncrRefCount(cmd);
Tcl_ResetResult(rtPtr->interp);
Tcl_SetObjResult(rtPtr->interp, Tcl_ObjPrintf(
"chan handler returned bad code: %d", result));
Tcl_LogCommandInfo(rtPtr->interp, cmdString, cmdString, cmdLen);
Tcl_DecrRefCount(cmd);
result = TCL_ERROR;
}
Tcl_AppendObjToErrorInfo(rtPtr->interp, Tcl_ObjPrintf(
"\n (chan handler subcommand \"%s\")", method));
resObj = MarshallError(rtPtr->interp);
}
Tcl_IncrRefCount(resObj);
}
Tcl_RestoreInterpState(rtPtr->interp, sr);
Tcl_Release(rtPtr->interp);
Tcl_Release(rtPtr);
/*
* Cleanup of the dynamic parts of the command.
*
* The detail objects survived the Tcl_EvalObjv without change because of
* the contract. Therefore there is no need to decrement the refcounts. Only
* the internal method object has to be disposed of.
*/
Tcl_DecrRefCount(methObj);
/*
* The resObj has a ref count of 1 at this location. This means that the
* caller of InvokeTclMethod has to dispose of it (but only if it was
* returned to it).
*/
if (resultObjPtr != NULL) {
*resultObjPtr = resObj;
}
/*
* There no need to handle the case where nothing is returned, because for
* that case resObj was not set anyway.
*/
return result;
}
/*
*----------------------------------------------------------------------
*
* GetReflectedTransformMap --
*
* Gets and potentially initializes the reflected channel map for an
* interpreter.
*
* Results:
* A pointer to the map created, for use by the caller.
*
* Side effects:
* Initializes the reflected channel map for an interpreter.
*
*----------------------------------------------------------------------
*/
static ReflectedTransformMap *
GetReflectedTransformMap(
Tcl_Interp *interp)
{
ReflectedTransformMap *rtmPtr = (ReflectedTransformMap *)Tcl_GetAssocData(interp, RTMKEY, NULL);
if (rtmPtr == NULL) {
rtmPtr = (ReflectedTransformMap *)ckalloc(sizeof(ReflectedTransformMap));
Tcl_InitHashTable(&rtmPtr->map, TCL_STRING_KEYS);
Tcl_SetAssocData(interp, RTMKEY,
(Tcl_InterpDeleteProc *) DeleteReflectedTransformMap, rtmPtr);
}
return rtmPtr;
}
/*
*----------------------------------------------------------------------
*
* DeleteReflectedTransformMap --
*
* 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
DeleteReflectedTransformMap(
ClientData clientData, /* The per-interpreter data structure. */
Tcl_Interp *interp) /* The interpreter being deleted. */
{
ReflectedTransformMap *rtmPtr; /* The map */
Tcl_HashSearch hSearch; /* Search variable. */
Tcl_HashEntry *hPtr; /* Search variable. */
ReflectedTransform *rtPtr;
#ifdef TCL_THREADS
ForwardingResult *resultPtr;
ForwardingEvent *evPtr;
ForwardParam *paramPtr;
#endif /* TCL_THREADS */
/*
* Delete all entries. The channels may have been closed already, or will
* be closed later, by the standard IO finalization of an interpreter
* under destruction. Except for the channels which were moved to a
* different interpreter and/or thread. They do not exist from the IO
* systems point of view and will not get closed. Therefore mark all as
* dead so that any future access will cause a proper error. For channels
* in a different thread we actually do the same as
* DeleteThreadReflectedTransformMap(), just restricted to the channels of
* this interp.
*/
rtmPtr = (ReflectedTransformMap *)clientData;
for (hPtr = Tcl_FirstHashEntry(&rtmPtr->map, &hSearch);
hPtr != NULL;
hPtr = Tcl_FirstHashEntry(&rtmPtr->map, &hSearch)) {
rtPtr = (ReflectedTransform *)Tcl_GetHashValue(hPtr);
rtPtr->dead = 1;
Tcl_DeleteHashEntry(hPtr);
}
Tcl_DeleteHashTable(&rtmPtr->map);
ckfree(&rtmPtr->map);
#ifdef TCL_THREADS
/*
* The origin interpreter for one or more reflected channels is gone.
*/
/*
* Get the map of all channels handled by the current thread. This is a
* ReflectedTransformMap, but on a per-thread basis, not per-interp. Go
* through the channels and remove all which were handled by this
* interpreter. They have already been marked as dead.
*/
rtmPtr = GetThreadReflectedTransformMap();
for (hPtr = Tcl_FirstHashEntry(&rtmPtr->map, &hSearch);
hPtr != NULL;
hPtr = Tcl_NextHashEntry(&hSearch)) {
rtPtr = (ReflectedTransform *)Tcl_GetHashValue(hPtr);
if (rtPtr->interp != interp) {
/*
* Ignore entries for other interpreters.
*/
continue;
}
rtPtr->dead = 1;
FreeReflectedTransformArgs(rtPtr);
Tcl_DeleteHashEntry(hPtr);
}
/*
* Go through the list of pending results and cancel all whose events were
* destined for this interpreter. While this is in progress we block any
* other access to the list of pending results.
*/
Tcl_MutexLock(&rtForwardMutex);
for (resultPtr = forwardList; resultPtr != NULL;
resultPtr = resultPtr->nextPtr) {
if (resultPtr->dsti != interp) {
/*
* Ignore results/events for other interpreters.
*/
continue;
}
/*
* The receiver for the event exited, before processing the event. We
* detach the result now, wake the originator up and signal failure.
*/
evPtr = resultPtr->evPtr;
if (evPtr == NULL) {
continue;
}
paramPtr = evPtr->param;
evPtr->resultPtr = NULL;
resultPtr->evPtr = NULL;
resultPtr->result = TCL_ERROR;
ForwardSetStaticError(paramPtr, msg_send_dstlost);
Tcl_ConditionNotify(&resultPtr->done);
}
Tcl_MutexUnlock(&rtForwardMutex);
#endif /* TCL_THREADS */
}
#ifdef TCL_THREADS
/*
*----------------------------------------------------------------------
*
* GetThreadReflectedTransformMap --
*
* Gets and potentially initializes the reflected channel map for a
* thread.
*
* Results:
* A pointer to the map created, for use by the caller.
*
* Side effects:
* Initializes the reflected channel map for a thread.
*
*----------------------------------------------------------------------
*/
static ReflectedTransformMap *
GetThreadReflectedTransformMap(void)
{
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (!tsdPtr->rtmPtr) {
tsdPtr->rtmPtr = (ReflectedTransformMap *)ckalloc(sizeof(ReflectedTransformMap));
Tcl_InitHashTable(&tsdPtr->rtmPtr->map, TCL_STRING_KEYS);
Tcl_CreateThreadExitHandler(DeleteThreadReflectedTransformMap, NULL);
}
return tsdPtr->rtmPtr;
}
/*
*----------------------------------------------------------------------
*
* DeleteThreadReflectedTransformMap --
*
* Deletes the channel table for a thread. This procedure is invoked when
* a thread is deleted. The channels have already been marked as dead, in
* DeleteReflectedTransformMap().
*
* Results:
* None.
*
* Side effects:
* Deletes the hash table of channels.
*
*----------------------------------------------------------------------
*/
static void
DeleteThreadReflectedTransformMap(
ClientData dummy) /* The per-thread data structure. */
{
Tcl_HashSearch hSearch; /* Search variable. */
Tcl_HashEntry *hPtr; /* Search variable. */
Tcl_ThreadId self = Tcl_GetCurrentThread();
ReflectedTransformMap *rtmPtr; /* The map */
ForwardingResult *resultPtr;
(void)dummy;
/*
* The origin thread for one or more reflected channels is gone.
* NOTE: If this function is called due to a thread getting killed the
* per-interp DeleteReflectedTransformMap is apparently not called.
*/
/*
* Get the map of all channels handled by the current thread. This is a
* ReflectedTransformMap, but on a per-thread basis, not per-interp. Go
* through the channels, remove all, mark them as dead.
*/
rtmPtr = GetThreadReflectedTransformMap();
for (hPtr = Tcl_FirstHashEntry(&rtmPtr->map, &hSearch);
hPtr != NULL;
hPtr = Tcl_FirstHashEntry(&rtmPtr->map, &hSearch)) {
ReflectedTransform *rtPtr = (ReflectedTransform *)Tcl_GetHashValue(hPtr);
rtPtr->dead = 1;
FreeReflectedTransformArgs(rtPtr);
Tcl_DeleteHashEntry(hPtr);
}
ckfree(rtmPtr);
/*
* Go through the list of pending results and cancel all whose events were
* destined for this thread. While this is in progress we block any
* other access to the list of pending results.
*/
Tcl_MutexLock(&rtForwardMutex);
for (resultPtr = forwardList; resultPtr != NULL;
resultPtr = resultPtr->nextPtr) {
ForwardingEvent *evPtr;
ForwardParam *paramPtr;
if (resultPtr->dst != self) {
/*
* Ignore results/events for other threads.
*/
continue;
}
/*
* The receiver for the event exited, before processing the event. We
* detach the result now, wake the originator up and signal failure.
*/
evPtr = resultPtr->evPtr;
if (evPtr == NULL) {
continue;
}
paramPtr = evPtr->param;
evPtr->resultPtr = NULL;
resultPtr->evPtr = NULL;
resultPtr->result = TCL_ERROR;
ForwardSetStaticError(paramPtr, msg_send_dstlost);
Tcl_ConditionNotify(&resultPtr->done);
}
Tcl_MutexUnlock(&rtForwardMutex);
}
static void
ForwardOpToOwnerThread(
ReflectedTransform *rtPtr, /* Channel instance */
ForwardedOperation op, /* Forwarded driver operation */
const void *param) /* Arguments */
{
Tcl_ThreadId dst = rtPtr->thread;
ForwardingEvent *evPtr;
ForwardingResult *resultPtr;
/*
* We gather the lock early. This allows us to check the liveness of the
* channel without interference from DeleteThreadReflectedTransformMap().
*/
Tcl_MutexLock(&rtForwardMutex);
if (rtPtr->dead) {
/*
* The channel is marked as dead. Bail out immediately, with an
* appropriate error. Do not forget to unlock the mutex on this path.
*/
ForwardSetStaticError((ForwardParam *) param, msg_send_dstlost);
Tcl_MutexUnlock(&rtForwardMutex);
return;
}
/*
* Create and initialize the event and data structures.
*/
evPtr = (ForwardingEvent *)ckalloc(sizeof(ForwardingEvent));
resultPtr = (ForwardingResult *)ckalloc(sizeof(ForwardingResult));
evPtr->event.proc = ForwardProc;
evPtr->resultPtr = resultPtr;
evPtr->op = op;
evPtr->rtPtr = rtPtr;
evPtr->param = (ForwardParam *) param;
resultPtr->src = Tcl_GetCurrentThread();
resultPtr->dst = dst;
resultPtr->dsti = rtPtr->interp;
resultPtr->done = NULL;
resultPtr->result = -1;
resultPtr->evPtr = evPtr;
/*
* Now execute the forward.
*/
TclSpliceIn(resultPtr, forwardList);
/* Do not unlock here. That is done by the ConditionWait */
/*
* Ensure cleanup of the event if the origin thread exits while this event
* is pending or in progress. Exit of the destination thread is handled by
* DeleteThreadReflectionChannelMap(), this is set up by
* GetThreadReflectedTransformMap(). This is what we use the 'forwardList'
* (see above) for.
*/
Tcl_CreateThreadExitHandler(SrcExitProc, evPtr);
/*
* Queue the event and poke the other thread's notifier.
*/
Tcl_ThreadQueueEvent(dst, (Tcl_Event *) evPtr, TCL_QUEUE_TAIL);
Tcl_ThreadAlert(dst);
/*
* (*) Block until the other thread has either processed the transfer or
* rejected it.
*/
while (resultPtr->result < 0) {
/*
* NOTE (1): Is it possible that the current thread goes away while
* waiting here? IOW Is it possible that "SrcExitProc" is called
* while we are here? See complementary note (2) in "SrcExitProc"
*
* The ConditionWait unlocks the mutex during the wait and relocks it
* immediately after.
*/
Tcl_ConditionWait(&resultPtr->done, &rtForwardMutex, NULL);
}
/*
* Unlink result from the forwarder list. No need to lock. Either still
* locked, or locked by the ConditionWait
*/
TclSpliceOut(resultPtr, forwardList);
resultPtr->nextPtr = NULL;
resultPtr->prevPtr = NULL;
Tcl_MutexUnlock(&rtForwardMutex);
Tcl_ConditionFinalize(&resultPtr->done);
/*
* Kill the cleanup handler now, and the result structure as well, before
* returning the success code.
*
* Note: The event structure has already been deleted by the destination
* notifier, after it serviced the event.
*/
Tcl_DeleteThreadExitHandler(SrcExitProc, evPtr);
ckfree(resultPtr);
}
static int
ForwardProc(
Tcl_Event *evGPtr,
int mask)
{
/*
* Notes regarding access to the referenced data.
*
* In principle the data belongs to the originating thread (see
* evPtr->src), however this thread is currently blocked at (*), i.e.
* quiescent. Because of this we can treat the data as belonging to us,
* without fear of race conditions. I.e. we can read and write as we like.
*
* The only thing we cannot be sure of is the resultPtr. This can be be
* NULLed if the originating thread went away while the event is handled
* here now.
*/
ForwardingEvent *evPtr = (ForwardingEvent *) evGPtr;
ForwardingResult *resultPtr = evPtr->resultPtr;
ReflectedTransform *rtPtr = evPtr->rtPtr;
Tcl_Interp *interp = rtPtr->interp;
ForwardParam *paramPtr = evPtr->param;
Tcl_Obj *resObj = NULL; /* Interp result of InvokeTclMethod */
ReflectedTransformMap *rtmPtr;
/* Map of reflected channels with handlers in
* this interp. */
Tcl_HashEntry *hPtr; /* Entry in the above map */
(void)mask;
/*
* Ignore the event if no one is waiting for its result anymore.
*/
if (!resultPtr) {
return 1;
}
paramPtr->base.code = TCL_OK;
paramPtr->base.msgStr = NULL;
paramPtr->base.mustFree = 0;
switch (evPtr->op) {
/*
* The destination thread for the following operations is
* rtPtr->thread, which contains rtPtr->interp, the interp we have to
* call upon for the driver.
*/
case ForwardedClose:
/*
* No parameters/results.
*/
if (InvokeTclMethod(rtPtr, "finalize", NULL, NULL,
&resObj) != TCL_OK) {
ForwardSetObjError(paramPtr, resObj);
}
/*
* Freeing is done here, in the origin thread, because the argv[]
* objects belong to this thread. Deallocating them in a different
* thread is not allowed
*/
/*
* Remove the channel from the map before releasing the memory, to
* prevent future accesses (like by 'postevent') from finding and
* dereferencing a dangling pointer.
*/
rtmPtr = GetReflectedTransformMap(interp);
hPtr = Tcl_FindHashEntry(&rtmPtr->map, Tcl_GetString(rtPtr->handle));
Tcl_DeleteHashEntry(hPtr);
/*
* In a threaded interpreter we manage a per-thread map as well, to
* allow us to survive if the script level pulls the rug out under a
* channel by deleting the owning thread.
*/
rtmPtr = GetThreadReflectedTransformMap();
hPtr = Tcl_FindHashEntry(&rtmPtr->map, Tcl_GetString(rtPtr->handle));
Tcl_DeleteHashEntry(hPtr);
FreeReflectedTransformArgs(rtPtr);
break;
case ForwardedInput: {
Tcl_Obj *bufObj = Tcl_NewByteArrayObj((unsigned char *)
paramPtr->transform.buf, paramPtr->transform.size);
Tcl_IncrRefCount(bufObj);
if (InvokeTclMethod(rtPtr, "read", bufObj, NULL, &resObj) != TCL_OK) {
ForwardSetObjError(paramPtr, resObj);
paramPtr->transform.size = -1;
} else {
/*
* Process a regular return. Contains the transformation result.
* Sent it back to the request originator.
*/
int bytec; /* Number of returned bytes */
unsigned char *bytev;
/* Array of returned bytes */
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
paramPtr->transform.size = bytec;
if (bytec > 0) {
paramPtr->transform.buf = (char *)ckalloc(bytec);
memcpy(paramPtr->transform.buf, bytev, bytec);
} else {
paramPtr->transform.buf = NULL;
}
}
Tcl_DecrRefCount(bufObj);
break;
}
case ForwardedOutput: {
Tcl_Obj *bufObj = Tcl_NewByteArrayObj((unsigned char *)
paramPtr->transform.buf, paramPtr->transform.size);
Tcl_IncrRefCount(bufObj);
if (InvokeTclMethod(rtPtr, "write", bufObj, NULL, &resObj) != TCL_OK) {
ForwardSetObjError(paramPtr, resObj);
paramPtr->transform.size = -1;
} else {
/*
* Process a regular return. Contains the transformation result.
* Sent it back to the request originator.
*/
int bytec; /* Number of returned bytes */
unsigned char *bytev;
/* Array of returned bytes */
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
paramPtr->transform.size = bytec;
if (bytec > 0) {
paramPtr->transform.buf = (char *)ckalloc(bytec);
memcpy(paramPtr->transform.buf, bytev, bytec);
} else {
paramPtr->transform.buf = NULL;
}
}
Tcl_DecrRefCount(bufObj);
break;
}
case ForwardedDrain:
if (InvokeTclMethod(rtPtr, "drain", NULL, NULL, &resObj) != TCL_OK) {
ForwardSetObjError(paramPtr, resObj);
paramPtr->transform.size = -1;
} else {
/*
* Process a regular return. Contains the transformation result.
* Sent it back to the request originator.
*/
int bytec; /* Number of returned bytes */
unsigned char *bytev; /* Array of returned bytes */
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
paramPtr->transform.size = bytec;
if (bytec > 0) {
paramPtr->transform.buf = (char *)ckalloc(bytec);
memcpy(paramPtr->transform.buf, bytev, bytec);
} else {
paramPtr->transform.buf = NULL;
}
}
break;
case ForwardedFlush:
if (InvokeTclMethod(rtPtr, "flush", NULL, NULL, &resObj) != TCL_OK) {
ForwardSetObjError(paramPtr, resObj);
paramPtr->transform.size = -1;
} else {
/*
* Process a regular return. Contains the transformation result.
* Sent it back to the request originator.
*/
int bytec; /* Number of returned bytes */
unsigned char *bytev;
/* Array of returned bytes */
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
paramPtr->transform.size = bytec;
if (bytec > 0) {
paramPtr->transform.buf = (char *)ckalloc(bytec);
memcpy(paramPtr->transform.buf, bytev, bytec);
} else {
paramPtr->transform.buf = NULL;
}
}
break;
case ForwardedClear:
(void) InvokeTclMethod(rtPtr, "clear", NULL, NULL, NULL);
break;
case ForwardedLimit:
if (InvokeTclMethod(rtPtr, "limit?", NULL, NULL, &resObj) != TCL_OK) {
ForwardSetObjError(paramPtr, resObj);
paramPtr->limit.max = -1;
} else if (Tcl_GetIntFromObj(interp, resObj,
&paramPtr->limit.max) != TCL_OK) {
ForwardSetObjError(paramPtr, MarshallError(interp));
paramPtr->limit.max = -1;
}
break;
default:
/*
* Bad operation code.
*/
Tcl_Panic("Bad operation code in ForwardProc");
break;
}
/*
* Remove the reference we held on the result of the invoke, if we had
* such.
*/
if (resObj != NULL) {
Tcl_DecrRefCount(resObj);
}
if (resultPtr) {
/*
* Report the forwarding result synchronously to the waiting caller.
* This unblocks (*) as well. This is wrapped into a conditional
* because the caller may have exited in the mean time.
*/
Tcl_MutexLock(&rtForwardMutex);
resultPtr->result = TCL_OK;
Tcl_ConditionNotify(&resultPtr->done);
Tcl_MutexUnlock(&rtForwardMutex);
}
return 1;
}
static void
SrcExitProc(
ClientData clientData)
{
ForwardingEvent *evPtr = (ForwardingEvent *)clientData;
ForwardingResult *resultPtr;
ForwardParam *paramPtr;
/*
* NOTE (2): Can this handler be called with the originator blocked?
*/
/*
* The originator for the event exited. It is not sure if this can happen,
* as the originator should be blocked at (*) while the event is in
* transit/pending.
*
* We make sure that the event cannot refer to the result anymore, remove
* it from the list of pending results and free the structure. Locking the
* access ensures that we cannot get in conflict with "ForwardProc",
* should it already execute the event.
*/
Tcl_MutexLock(&rtForwardMutex);
resultPtr = evPtr->resultPtr;
paramPtr = evPtr->param;
evPtr->resultPtr = NULL;
resultPtr->evPtr = NULL;
resultPtr->result = TCL_ERROR;
ForwardSetStaticError(paramPtr, msg_send_originlost);
/*
* See below: TclSpliceOut(resultPtr, forwardList);
*/
Tcl_MutexUnlock(&rtForwardMutex);
/*
* This unlocks (*). The structure will be spliced out and freed by
* "ForwardProc". Maybe.
*/
Tcl_ConditionNotify(&resultPtr->done);
}
static void
ForwardSetObjError(
ForwardParam *paramPtr,
Tcl_Obj *obj)
{
int len;
const char *msgStr = Tcl_GetStringFromObj(obj, &len);
len++;
ForwardSetDynamicError(paramPtr, ckalloc(len));
memcpy(paramPtr->base.msgStr, msgStr, len);
}
#endif /* TCL_THREADS */
/*
*----------------------------------------------------------------------
*
* TimerKill --
*
* Timer management. Removes the internal timer if it exists.
*
* Side effects:
* See above.
*
* Result:
* None.
*
*----------------------------------------------------------------------
*/
static void
TimerKill(
ReflectedTransform *rtPtr)
{
if (rtPtr->timer == NULL) {
return;
}
/*
* Delete an existing flush-out timer, prevent it from firing on a
* removed/dead channel.
*/
Tcl_DeleteTimerHandler(rtPtr->timer);
rtPtr->timer = NULL;
}
/*
*----------------------------------------------------------------------
*
* TimerSetup --
*
* Timer management. Creates the internal timer if it does not exist.
*
* Side effects:
* See above.
*
* Result:
* None.
*
*----------------------------------------------------------------------
*/
static void
TimerSetup(
ReflectedTransform *rtPtr)
{
if (rtPtr->timer != NULL) {
return;
}
rtPtr->timer = Tcl_CreateTimerHandler(SYNTHETIC_EVENT_TIME,
TimerRun, rtPtr);
}
/*
*----------------------------------------------------------------------
*
* TimerRun --
*
* Called by the notifier (-> timer) to flush out information waiting in
* channel buffers.
*
* Side effects:
* As of 'Tcl_NotifyChannel'.
*
* Result:
* None.
*
*----------------------------------------------------------------------
*/
static void
TimerRun(
ClientData clientData)
{
ReflectedTransform *rtPtr = (ReflectedTransform *)clientData;
rtPtr->timer = NULL;
Tcl_NotifyChannel(rtPtr->chan, TCL_READABLE);
}
/*
*----------------------------------------------------------------------
*
* ResultInit --
*
* Initializes the specified buffer structure. The structure will contain
* valid information for an emtpy buffer.
*
* Side effects:
* See above.
*
* Result:
* None.
*
*----------------------------------------------------------------------
*/
static void
ResultInit(
ResultBuffer *rPtr) /* Reference to the structure to
* initialize. */
{
rPtr->used = 0;
rPtr->allocated = 0;
rPtr->buf = NULL;
}
/*
*----------------------------------------------------------------------
*
* ResultClear --
*
* Deallocates any memory allocated by 'ResultAdd'.
*
* Side effects:
* See above.
*
* Result:
* None.
*
*----------------------------------------------------------------------
*/
static void
ResultClear(
ResultBuffer *rPtr) /* Reference to the buffer to clear out */
{
rPtr->used = 0;
if (!rPtr->allocated) {
return;
}
ckfree((char *) rPtr->buf);
rPtr->buf = NULL;
rPtr->allocated = 0;
}
/*
*----------------------------------------------------------------------
*
* ResultAdd --
*
* Adds the bytes in the specified array to the buffer, by appending it.
*
* Side effects:
* See above.
*
* Result:
* None.
*
*----------------------------------------------------------------------
*/
static void
ResultAdd(
ResultBuffer *rPtr, /* The buffer to extend */
unsigned char *buf, /* The buffer to read from */
int toWrite) /* The number of bytes in 'buf' */
{
if ((rPtr->used + toWrite + 1) > rPtr->allocated) {
/*
* Extension of the internal buffer is required.
* NOTE: Currently linear. Should be doubling to amortize.
*/
if (rPtr->allocated == 0) {
rPtr->allocated = toWrite + RB_INCREMENT;
rPtr->buf = UCHARP(ckalloc(rPtr->allocated));
} else {
rPtr->allocated += toWrite + RB_INCREMENT;
rPtr->buf = UCHARP(ckrealloc((char *) rPtr->buf,
rPtr->allocated));
}
}
/*
* Now copy data.
*/
memcpy(rPtr->buf + rPtr->used, buf, toWrite);
rPtr->used += toWrite;
}
/*
*----------------------------------------------------------------------
*
* ResultCopy --
*
* Copies the requested number of bytes from the buffer into the
* specified array and removes them from the buffer afterward. Copies
* less if there is not enough data in the buffer.
*
* Side effects:
* See above.
*
* Result:
* The number of actually copied bytes, possibly less than 'toRead'.
*
*----------------------------------------------------------------------
*/
static int
ResultCopy(
ResultBuffer *rPtr, /* The buffer to read from */
unsigned char *buf, /* The buffer to copy into */
int toRead) /* Number of requested bytes */
{
int copied;
if (rPtr->used == 0) {
/*
* Nothing to copy in the case of an empty buffer.
*/
copied = 0;
} else if (rPtr->used == toRead) {
/*
* We have just enough. Copy everything to the caller.
*/
memcpy(buf, rPtr->buf, toRead);
rPtr->used = 0;
copied = toRead;
} else if (rPtr->used > toRead) {
/*
* The internal buffer contains more than requested. Copy the
* requested subset to the caller, and shift the remaining bytes down.
*/
memcpy(buf, rPtr->buf, toRead);
memmove(rPtr->buf, rPtr->buf + toRead, rPtr->used - toRead);
rPtr->used -= toRead;
copied = toRead;
} else {
/*
* There is not enough in the buffer to satisfy the caller, so take
* everything.
*/
memcpy(buf, rPtr->buf, rPtr->used);
toRead = rPtr->used;
rPtr->used = 0;
copied = toRead;
}
/* -- common postwork code ------- */
return copied;
}
static int
TransformRead(
ReflectedTransform *rtPtr,
int *errorCodePtr,
Tcl_Obj *bufObj)
{
Tcl_Obj *resObj;
int bytec; /* Number of returned bytes */
unsigned char *bytev; /* Array of returned bytes */
/*
* Are we in the correct thread?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
p.transform.buf = (char *) Tcl_GetByteArrayFromObj(bufObj,
&(p.transform.size));
ForwardOpToOwnerThread(rtPtr, ForwardedInput, &p);
if (p.base.code != TCL_OK) {
PassReceivedError(rtPtr->chan, &p);
*errorCodePtr = EINVAL;
return 0;
}
*errorCodePtr = EOK;
ResultAdd(&rtPtr->result, UCHARP(p.transform.buf), p.transform.size);
ckfree(p.transform.buf);
return 1;
}
#endif /* TCL_THREADS */
/* ASSERT: rtPtr->method & FLAG(METH_READ) */
/* ASSERT: rtPtr->mode & TCL_READABLE */
if (InvokeTclMethod(rtPtr, "read", bufObj, NULL, &resObj) != TCL_OK) {
Tcl_SetChannelError(rtPtr->chan, resObj);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
*errorCodePtr = EINVAL;
return 0;
}
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
ResultAdd(&rtPtr->result, bytev, bytec);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
return 1;
}
static int
TransformWrite(
ReflectedTransform *rtPtr,
int *errorCodePtr,
unsigned char *buf,
int toWrite)
{
Tcl_Obj *bufObj;
Tcl_Obj *resObj;
int bytec; /* Number of returned bytes */
unsigned char *bytev; /* Array of returned bytes */
int res;
/*
* Are we in the correct thread?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
p.transform.buf = (char *) buf;
p.transform.size = toWrite;
ForwardOpToOwnerThread(rtPtr, ForwardedOutput, &p);
if (p.base.code != TCL_OK) {
PassReceivedError(rtPtr->chan, &p);
*errorCodePtr = EINVAL;
return 0;
}
*errorCodePtr = EOK;
res = Tcl_WriteRaw(rtPtr->parent, (char *) p.transform.buf,
p.transform.size);
ckfree(p.transform.buf);
} else
#endif /* TCL_THREADS */
{
/* ASSERT: rtPtr->method & FLAG(METH_WRITE) */
/* ASSERT: rtPtr->mode & TCL_WRITABLE */
bufObj = Tcl_NewByteArrayObj((unsigned char *) buf, toWrite);
Tcl_IncrRefCount(bufObj);
if (InvokeTclMethod(rtPtr, "write", bufObj, NULL, &resObj) != TCL_OK) {
*errorCodePtr = EINVAL;
Tcl_SetChannelError(rtPtr->chan, resObj);
Tcl_DecrRefCount(bufObj);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
return 0;
}
*errorCodePtr = EOK;
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
res = Tcl_WriteRaw(rtPtr->parent, (char *) bytev, bytec);
Tcl_DecrRefCount(bufObj);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
}
if (res < 0) {
*errorCodePtr = Tcl_GetErrno();
return 0;
}
return 1;
}
static int
TransformDrain(
ReflectedTransform *rtPtr,
int *errorCodePtr)
{
Tcl_Obj *resObj;
int bytec; /* Number of returned bytes */
unsigned char *bytev; /* Array of returned bytes */
/*
* Are we in the correct thread?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
ForwardOpToOwnerThread(rtPtr, ForwardedDrain, &p);
if (p.base.code != TCL_OK) {
PassReceivedError(rtPtr->chan, &p);
*errorCodePtr = EINVAL;
return 0;
}
*errorCodePtr = EOK;
ResultAdd(&rtPtr->result, UCHARP(p.transform.buf), p.transform.size);
ckfree(p.transform.buf);
} else
#endif /* TCL_THREADS */
{
if (InvokeTclMethod(rtPtr, "drain", NULL, NULL, &resObj)!=TCL_OK) {
Tcl_SetChannelError(rtPtr->chan, resObj);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
*errorCodePtr = EINVAL;
return 0;
}
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
ResultAdd(&rtPtr->result, bytev, bytec);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
}
rtPtr->readIsDrained = 1;
return 1;
}
static int
TransformFlush(
ReflectedTransform *rtPtr,
int *errorCodePtr,
int op)
{
Tcl_Obj *resObj;
int bytec; /* Number of returned bytes */
unsigned char *bytev; /* Array of returned bytes */
int res;
/*
* Are we in the correct thread?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
ForwardOpToOwnerThread(rtPtr, ForwardedFlush, &p);
if (p.base.code != TCL_OK) {
PassReceivedError(rtPtr->chan, &p);
*errorCodePtr = EINVAL;
return 0;
}
*errorCodePtr = EOK;
if (op == FLUSH_WRITE) {
res = Tcl_WriteRaw(rtPtr->parent, (char *) p.transform.buf,
p.transform.size);
} else {
res = 0;
}
ckfree(p.transform.buf);
} else
#endif /* TCL_THREADS */
{
if (InvokeTclMethod(rtPtr, "flush", NULL, NULL, &resObj)!=TCL_OK) {
Tcl_SetChannelError(rtPtr->chan, resObj);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
*errorCodePtr = EINVAL;
return 0;
}
if (op == FLUSH_WRITE) {
bytev = Tcl_GetByteArrayFromObj(resObj, &bytec);
res = Tcl_WriteRaw(rtPtr->parent, (char *) bytev, bytec);
} else {
res = 0;
}
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
}
if (res < 0) {
*errorCodePtr = Tcl_GetErrno();
return 0;
}
return 1;
}
static void
TransformClear(
ReflectedTransform *rtPtr)
{
/*
* Are we in the correct thread?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
ForwardOpToOwnerThread(rtPtr, ForwardedClear, &p);
return;
}
#endif /* TCL_THREADS */
/* ASSERT: rtPtr->method & FLAG(METH_READ) */
/* ASSERT: rtPtr->mode & TCL_READABLE */
(void) InvokeTclMethod(rtPtr, "clear", NULL, NULL, NULL);
rtPtr->readIsDrained = 0;
rtPtr->eofPending = 0;
ResultClear(&rtPtr->result);
}
static int
TransformLimit(
ReflectedTransform *rtPtr,
int *errorCodePtr,
int *maxPtr)
{
Tcl_Obj *resObj;
Tcl_InterpState sr; /* State of handler interp */
/*
* Are we in the correct thread?
*/
#ifdef TCL_THREADS
if (rtPtr->thread != Tcl_GetCurrentThread()) {
ForwardParam p;
ForwardOpToOwnerThread(rtPtr, ForwardedLimit, &p);
if (p.base.code != TCL_OK) {
PassReceivedError(rtPtr->chan, &p);
*errorCodePtr = EINVAL;
return 0;
}
*errorCodePtr = EOK;
*maxPtr = p.limit.max;
return 1;
}
#endif
/* ASSERT: rtPtr->method & FLAG(METH_WRITE) */
/* ASSERT: rtPtr->mode & TCL_WRITABLE */
if (InvokeTclMethod(rtPtr, "limit?", NULL, NULL, &resObj) != TCL_OK) {
Tcl_SetChannelError(rtPtr->chan, resObj);
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
*errorCodePtr = EINVAL;
return 0;
}
sr = Tcl_SaveInterpState(rtPtr->interp, 0 /* Dummy */);
if (Tcl_GetIntFromObj(rtPtr->interp, resObj, maxPtr) != TCL_OK) {
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
Tcl_SetChannelError(rtPtr->chan, MarshallError(rtPtr->interp));
*errorCodePtr = EINVAL;
Tcl_RestoreInterpState(rtPtr->interp, sr);
return 0;
}
Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */
Tcl_RestoreInterpState(rtPtr->interp, sr);
return 1;
}
/*
* Local Variables:
* mode: c
* c-basic-offset: 4
* fill-column: 78
* End:
*/