* fixed malloc corruption in target->debug_reason

* GDB remote server will now remain online even if the target
	  is in a funny state, e.g. if it requires a reset, it is
	  running while GDB is not in the continue or step packet,
	  e.g. via monitor resume/halt commands in GDB script.
	* Added some _DEBUG_GDB_IO_ debug tools
	* Fixed a couple of GDB server lockups, e.g. when O packets
	  detect a severed connection
	* added ACK upon connection (send +).
	* added keep-alive messages to reset so GDB protocol remains happy.
	* fixed crash when timing out connection to GDB

git-svn-id: svn://svn.berlios.de/openocd/trunk@445 b42882b7-edfa-0310-969c-e2dbd0fdcd60
This commit is contained in:
oharboe 2008-03-05 10:28:32 +00:00
parent 6445cc6479
commit 6d95014674
5 changed files with 130 additions and 116 deletions

View File

@ -447,7 +447,6 @@ void command_print_help_line(command_context_t* context, struct command_s *comma
char indent_text[indent + 2];
char *help = "no help available";
char name_buf[64];
int i;
if (indent)
{
@ -478,7 +477,6 @@ void command_print_help_line(command_context_t* context, struct command_s *comma
int command_print_help_match(command_context_t* context, command_t* c_first, char* name, char** args, int argc)
{
command_t * c;
int i;
for (c = c_first; c; c = c->next)
{

View File

@ -43,6 +43,7 @@
#define _DEBUG_GDB_IO_
#endif
extern int gdb_error(connection_t *connection, int retval);
static unsigned short gdb_port;
static const char *DIGITS = "0123456789abcdef";
@ -84,14 +85,58 @@ int gdb_last_signal(target_t *target)
case DBG_REASON_NOTHALTED:
return 0x0; /* no signal... shouldn't happen */
default:
ERROR("BUG: undefined debug reason");
exit(-1);
USER("undefined debug reason %d - target needs reset", target->debug_reason);
return 0x0;
}
}
#ifndef _WIN32
int check_pending(connection_t *connection, int timeout_s, int *got_data)
{
/* a non-blocking socket will block if there is 0 bytes available on the socket,
* but return with as many bytes as are available immediately
*/
struct timeval tv;
fd_set read_fds;
gdb_connection_t *gdb_con = connection->priv;
int t;
if (got_data==NULL)
got_data=&t;
*got_data=0;
if (gdb_con->buf_cnt>0)
{
*got_data = 1;
return ERROR_OK;
}
FD_ZERO(&read_fds);
FD_SET(connection->fd, &read_fds);
tv.tv_sec = timeout_s;
tv.tv_usec = 0;
if (select(connection->fd + 1, &read_fds, NULL, NULL, &tv) == 0)
{
/* This can typically be because a "monitor" command took too long
* before printing any progress messages
*/
if (timeout_s>0)
{
return ERROR_GDB_TIMEOUT;
} else
{
return ERROR_OK;
}
}
*got_data=FD_ISSET(connection->fd, &read_fds)!=0;
return ERROR_OK;
}
#endif
int gdb_get_char(connection_t *connection, int* next_char)
{
gdb_connection_t *gdb_con = connection->priv;
int retval=ERROR_OK;
#ifdef _DEBUG_GDB_IO_
char *debug_buffer;
@ -115,24 +160,9 @@ int gdb_get_char(connection_t *connection, int* next_char)
for (;;)
{
#ifndef _WIN32
/* a non-blocking socket will block if there is 0 bytes available on the socket,
* but return with as many bytes as are available immediately
*/
struct timeval tv;
fd_set read_fds;
FD_ZERO(&read_fds);
FD_SET(connection->fd, &read_fds);
tv.tv_sec = 1;
tv.tv_usec = 0;
if (select(connection->fd + 1, &read_fds, NULL, NULL, &tv) == 0)
{
/* This can typically be because a "monitor" command took too long
* before printing any progress messages
*/
return ERROR_GDB_TIMEOUT;
}
retval=check_pending(connection, 1, NULL);
if (retval!=ERROR_OK)
return retval;
#endif
gdb_con->buf_cnt = read_socket(connection->fd, gdb_con->buffer, GDB_BUFFER_SIZE);
if (gdb_con->buf_cnt > 0)
@ -154,8 +184,10 @@ int gdb_get_char(connection_t *connection, int* next_char)
usleep(1000);
break;
case WSAECONNABORTED:
gdb_con->closed = 1;
return ERROR_SERVER_REMOTE_CLOSED;
case WSAECONNRESET:
gdb_con->closed = 1;
return ERROR_SERVER_REMOTE_CLOSED;
default:
ERROR("read: %d", errno);
@ -168,11 +200,14 @@ int gdb_get_char(connection_t *connection, int* next_char)
usleep(1000);
break;
case ECONNABORTED:
gdb_con->closed = 1;
return ERROR_SERVER_REMOTE_CLOSED;
case ECONNRESET:
gdb_con->closed = 1;
return ERROR_SERVER_REMOTE_CLOSED;
default:
ERROR("read: %s", strerror(errno));
gdb_con->closed = 1;
return ERROR_SERVER_REMOTE_CLOSED;
}
#endif
@ -197,7 +232,7 @@ int gdb_get_char(connection_t *connection, int* next_char)
DEBUG("returned char '%c' (0x%2.2x)", *next_char, *next_char);
#endif
return ERROR_OK;
return retval;
}
int gdb_putback_char(connection_t *connection, int last_char)
@ -248,6 +283,27 @@ int gdb_put_packet_inner(connection_t *connection, char *buffer, int len)
for (i = 0; i < len; i++)
my_checksum += buffer[i];
#ifdef _DEBUG_GDB_IO_
/*
* At this point we should have nothing in the input queue from GDB,
* however sometimes '-' is sent even though we've already received
* an ACK (+) for everything we've sent off.
*/
#ifndef _WIN32
int gotdata;
for (;;)
{
if ((retval=check_pending(connection, 0, &gotdata))!=ERROR_OK)
return retval;
if (!gotdata)
break;
if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK)
return retval;
WARNING("Discard unexpected char %c", reply);
}
#endif
#endif
while (1)
{
#ifdef _DEBUG_GDB_IO_
@ -257,17 +313,7 @@ int gdb_put_packet_inner(connection_t *connection, char *buffer, int len)
DEBUG("sending packet '$%s#%2.2x'", debug_buffer, my_checksum);
free(debug_buffer);
#endif
#if 0
char checksum[3];
gdb_write(connection, "$", 1);
if (len > 0)
gdb_write(connection, buffer, len);
gdb_write(connection, "#", 1);
snprintf(checksum, 3, "%2.2x", my_checksum);
gdb_write(connection, checksum, 2);
#else
void *allocated = NULL;
char stackAlloc[1024];
char *t = stackAlloc;
@ -294,7 +340,7 @@ int gdb_put_packet_inner(connection_t *connection, char *buffer, int len)
{
free(allocated);
}
#endif
if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK)
return retval;
@ -322,12 +368,14 @@ int gdb_put_packet_inner(connection_t *connection, char *buffer, int len)
else
{
ERROR("unknown character 0x%2.2x in reply, dropping connection", reply);
gdb_con->closed=1;
return ERROR_SERVER_REMOTE_CLOSED;
}
}
else
{
ERROR("unknown character 0x%2.2x in reply, dropping connection", reply);
gdb_con->closed=1;
return ERROR_SERVER_REMOTE_CLOSED;
}
}
@ -625,27 +673,36 @@ int gdb_new_connection(connection_t *connection)
gdb_connection->closed = 0;
gdb_connection->busy = 0;
/* send ACK to GDB for debug request */
gdb_write(connection, "+", 1);
/* output goes through gdb connection */
command_set_output_handler(connection->cmd_ctx, gdb_output, connection);
/* register callback to be informed about target events */
target_register_event_callback(gdb_target_callback_event_handler, connection);
/* a gdb session just attached, put the target in halt mode */
/* a gdb session just attached, try to put the target in halt mode
* or alterantively try to issue a reset.
*
* GDB connection will fail if e.g. register read packets fail,
* otherwise resetting/halting the target could have been left to GDB init
* scripts
*/
if (((retval = gdb_service->target->type->halt(gdb_service->target)) != ERROR_OK) &&
(retval != ERROR_TARGET_ALREADY_HALTED))
{
ERROR("error(%d) when trying to halt target, falling back to \"reset halt\"", retval);
command_run_line(connection->cmd_ctx, "reset halt");
ERROR("error(%d) when trying to halt target, falling back to \"reset\"", retval);
command_run_line(connection->cmd_ctx, "reset");
}
/* This will time out after 1 second */
command_run_line(connection->cmd_ctx, "wait_halt 1");
/* remove the initial ACK from the incoming buffer */
if ((retval = gdb_get_char(connection, &initial_ack)) != ERROR_OK)
return retval;
/* FIX!!!??? would we actually ever receive a + here???
* Not observed.
*/
if (initial_ack != '+')
gdb_putback_char(connection, initial_ack);
@ -778,16 +835,7 @@ int gdb_get_registers_packet(connection_t *connection, target_t *target, char* p
if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
{
switch (retval)
{
case ERROR_TARGET_NOT_HALTED:
ERROR("gdb requested registers but we're not halted, dropping connection");
return ERROR_SERVER_REMOTE_CLOSED;
default:
/* this is a bug condition - get_gdb_reg_list() may not return any other error */
ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
exit(-1);
}
return gdb_error(connection, retval);
}
for (i = 0; i < reg_list_size; i++)
@ -845,16 +893,7 @@ int gdb_set_registers_packet(connection_t *connection, target_t *target, char *p
if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
{
switch (retval)
{
case ERROR_TARGET_NOT_HALTED:
ERROR("gdb tried to registers but we're not halted, dropping connection");
return ERROR_SERVER_REMOTE_CLOSED;
default:
/* this is a bug condition - get_gdb_reg_list() may not return any other error */
ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
exit(-1);
}
return gdb_error(connection, retval);
}
packet_p = packet;
@ -910,16 +949,7 @@ int gdb_get_register_packet(connection_t *connection, target_t *target, char *pa
if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
{
switch (retval)
{
case ERROR_TARGET_NOT_HALTED:
ERROR("gdb requested registers but we're not halted, dropping connection");
return ERROR_SERVER_REMOTE_CLOSED;
default:
/* this is a bug condition - get_gdb_reg_list() may not return any other error */
ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
exit(-1);
}
return gdb_error(connection, retval);
}
if (reg_list_size <= reg_num)
@ -955,16 +985,7 @@ int gdb_set_register_packet(connection_t *connection, target_t *target, char *pa
if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
{
switch (retval)
{
case ERROR_TARGET_NOT_HALTED:
ERROR("gdb tried to set a register but we're not halted, dropping connection");
return ERROR_SERVER_REMOTE_CLOSED;
default:
/* this is a bug condition - get_gdb_reg_list() may not return any other error */
ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
exit(-1);
}
return gdb_error(connection, retval);
}
if (reg_list_size < reg_num)
@ -1005,13 +1026,10 @@ int gdb_set_register_packet(connection_t *connection, target_t *target, char *pa
return ERROR_OK;
}
int gdb_memory_packet_error(connection_t *connection, int retval)
int gdb_error(connection_t *connection, int retval)
{
switch (retval)
{
case ERROR_TARGET_NOT_HALTED:
ERROR("gdb tried to read memory but we're not halted, dropping connection");
return ERROR_SERVER_REMOTE_CLOSED;
case ERROR_TARGET_DATA_ABORT:
gdb_send_error(connection, EIO);
break;
@ -1021,10 +1039,14 @@ int gdb_memory_packet_error(connection_t *connection, int retval)
case ERROR_TARGET_UNALIGNED_ACCESS:
gdb_send_error(connection, EFAULT);
break;
case ERROR_TARGET_NOT_HALTED:
gdb_send_error(connection, EFAULT);
break;
default:
/* This could be that the target reset itself. */
ERROR("unexpected error %i. Dropping connection.", retval);
return ERROR_SERVER_REMOTE_CLOSED;
ERROR("unexpected error %i", retval);
gdb_send_error(connection, EFAULT);
break;
}
return ERROR_OK;
@ -1101,7 +1123,7 @@ int gdb_read_memory_packet(connection_t *connection, target_t *target, char *pac
}
else
{
retval = gdb_memory_packet_error(connection, retval);
retval = gdb_error(connection, retval);
}
free(buffer);
@ -1158,7 +1180,7 @@ int gdb_write_memory_packet(connection_t *connection, target_t *target, char *pa
}
else
{
if ((retval = gdb_memory_packet_error(connection, retval)) != ERROR_OK)
if ((retval = gdb_error(connection, retval)) != ERROR_OK)
return retval;
}
@ -1208,7 +1230,7 @@ int gdb_write_memory_binary_packet(connection_t *connection, target_t *target, c
}
else
{
if ((retval = gdb_memory_packet_error(connection, retval)) != ERROR_OK)
if ((retval = gdb_error(connection, retval)) != ERROR_OK)
return retval;
}
@ -1244,25 +1266,6 @@ void gdb_step_continue_packet(connection_t *connection, target_t *target, char *
}
}
int gdb_bp_wp_packet_error(connection_t *connection, int retval)
{
switch (retval)
{
case ERROR_TARGET_NOT_HALTED:
ERROR("gdb tried to set a breakpoint but we're not halted, dropping connection");
return ERROR_SERVER_REMOTE_CLOSED;
break;
case ERROR_TARGET_RESOURCE_NOT_AVAILABLE:
gdb_send_error(connection, EBUSY);
break;
default:
ERROR("BUG: unexpected error %i", retval);
exit(-1);
}
return ERROR_OK;
}
int gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
int type;
@ -1312,7 +1315,7 @@ int gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target,
{
if ((retval = breakpoint_add(target, address, size, bp_type)) != ERROR_OK)
{
if ((retval = gdb_bp_wp_packet_error(connection, retval)) != ERROR_OK)
if ((retval = gdb_error(connection, retval)) != ERROR_OK)
return retval;
}
else
@ -1334,7 +1337,7 @@ int gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target,
{
if ((retval = watchpoint_add(target, address, size, type-2, 0, 0xffffffffu)) != ERROR_OK)
{
if ((retval = gdb_bp_wp_packet_error(connection, retval)) != ERROR_OK)
if ((retval = gdb_error(connection, retval)) != ERROR_OK)
return retval;
}
else
@ -1502,7 +1505,7 @@ int gdb_query_packet(connection_t *connection, target_t *target, char *packet, i
}
else
{
if ((retval = gdb_memory_packet_error(connection, retval)) != ERROR_OK)
if ((retval = gdb_error(connection, retval)) != ERROR_OK)
return retval;
}
@ -1939,8 +1942,14 @@ int gdb_input_inner(connection_t *connection)
int gdb_input(connection_t *connection)
{
int retval = gdb_input_inner(connection);
gdb_connection_t *gdb_con = connection->priv;
if (retval == ERROR_SERVER_REMOTE_CLOSED)
return retval;
/* logging does not propagate the error, yet can set th gdb_con->closed flag */
if (gdb_con->closed)
return ERROR_SERVER_REMOTE_CLOSED;
/* we'll recover from any other errors(e.g. temporary timeouts, etc.) */
return ERROR_OK;
}

View File

@ -71,6 +71,7 @@ int add_connection(service_t *service, command_context_t *cmd_ctx)
close_socket(c->fd);
INFO("attempted '%s' connection rejected", service->name);
free(c);
return retval;
}
/* add to the end of linked list */

View File

@ -122,7 +122,7 @@ char *target_debug_reason_strings[] =
{
"debug request", "breakpoint", "watchpoint",
"watchpoint and breakpoint", "single step",
"target not halted"
"target not halted", "undefined"
};
char *target_endianess_strings[] =
@ -362,7 +362,11 @@ int target_process_reset(struct command_context_s *cmd_ctx)
command_print(cmd_ctx, "Timed out waiting for reset");
goto done;
}
usleep(100*1000); /* Do not eat all cpu */
/* this will send alive messages on e.g. GDB remote protocol.
* GDB warns me that I'm sending a zero length formatting message,
* which is strange, but in fact what is intended here. */
usleep(500*1000);
USER_N("");
goto again;
}
}
@ -1178,6 +1182,7 @@ int handle_target_command(struct command_context_s *cmd_ctx, char *cmd, char **a
(*last_target_p)->backup_working_area = 0;
(*last_target_p)->state = TARGET_UNKNOWN;
(*last_target_p)->debug_reason = DBG_REASON_UNDEFINED;
(*last_target_p)->reg_cache = NULL;
(*last_target_p)->breakpoints = NULL;
(*last_target_p)->watchpoints = NULL;

View File

@ -78,7 +78,8 @@ enum target_debug_reason
DBG_REASON_WATCHPOINT = 2,
DBG_REASON_WPTANDBKPT = 3,
DBG_REASON_SINGLESTEP = 4,
DBG_REASON_NOTHALTED = 5
DBG_REASON_NOTHALTED = 5,
DBG_REASON_UNDEFINED = 6
};
extern char *target_debug_reason_strings[];