/* Exception (throw catch) mechanism, for GDB, the GNU debugger.
- Copyright 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
- 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free
- Software Foundation, Inc.
+ Copyright (C) 1986, 1988-2012 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "exceptions.h"
-#include <setjmp.h>
#include "breakpoint.h"
#include "target.h"
#include "inferior.h"
#include "ui-out.h"
#include "gdb_assert.h"
#include "gdb_string.h"
+#include "serial.h"
+#include "gdbthread.h"
-const struct exception exception_none = { 0, NO_ERROR, NULL };
-
-/* One should use catch_errors rather than manipulating these
- directly. */
-#if defined(HAVE_SIGSETJMP)
-#define SIGJMP_BUF sigjmp_buf
-#define SIGSETJMP(buf) sigsetjmp((buf), 1)
-#define SIGLONGJMP(buf,val) siglongjmp((buf), (val))
-#else
-#define SIGJMP_BUF jmp_buf
-#define SIGSETJMP(buf) setjmp(buf)
-#define SIGLONGJMP(buf,val) longjmp((buf), (val))
-#endif
+const struct gdb_exception exception_none = { 0, GDB_NO_ERROR, NULL };
/* Possible catcher states. */
enum catcher_state {
{
enum catcher_state state;
/* Jump buffer pointing back at the exception handler. */
- SIGJMP_BUF buf;
+ EXCEPTIONS_SIGJMP_BUF buf;
/* Status buffer belonging to the exception handler. */
- volatile struct exception *exception;
- /* Should the error / quit message be printed? Old code assumes
- that this file prints the error/quit message when first reported.
- New code instead directly handles the printing of error/quit
- messages. */
- int print_message;
+ volatile struct gdb_exception *exception;
/* Saved/current state. */
int mask;
- char *saved_error_pre_print;
- char *saved_quit_pre_print;
- struct ui_out *saved_uiout;
struct cleanup *saved_cleanup_chain;
/* Back link. */
struct catcher *prev;
/* Where to go for throw_exception(). */
static struct catcher *current_catcher;
-static SIGJMP_BUF *
-catcher_init (struct ui_out *func_uiout,
- char *errstring,
- volatile struct exception *exception,
- return_mask mask,
- int print_message)
+/* Return length of current_catcher list. */
+
+static int
+catcher_list_size (void)
+{
+ int size;
+ struct catcher *catcher;
+
+ for (size = 0, catcher = current_catcher;
+ catcher != NULL;
+ catcher = catcher->prev)
+ ++size;
+
+ return size;
+}
+
+EXCEPTIONS_SIGJMP_BUF *
+exceptions_state_mc_init (volatile struct gdb_exception *exception,
+ return_mask mask)
{
struct catcher *new_catcher = XZALLOC (struct catcher);
/* Start with no exception, save it's address. */
exception->reason = 0;
- exception->error = NO_ERROR;
+ exception->error = GDB_NO_ERROR;
exception->message = NULL;
new_catcher->exception = exception;
new_catcher->mask = mask;
- new_catcher->print_message = print_message;
-
- /* Override error/quit messages during FUNC. */
- new_catcher->saved_error_pre_print = error_pre_print;
- new_catcher->saved_quit_pre_print = quit_pre_print;
- if (mask & RETURN_MASK_ERROR)
- error_pre_print = errstring;
- if (mask & RETURN_MASK_QUIT)
- quit_pre_print = errstring;
-
- /* Override the global ``struct ui_out'' builder. */
- new_catcher->saved_uiout = uiout;
- uiout = func_uiout;
/* Prevent error/quit during FUNC from calling cleanups established
- prior to here. */
+ prior to here. */
new_catcher->saved_cleanup_chain = save_cleanups ();
/* Push this new catcher on the top. */
catcher_pop (void)
{
struct catcher *old_catcher = current_catcher;
+
current_catcher = old_catcher->prev;
/* Restore the cleanup chain, the error/quit messages, and the uiout
- builder, to their original states. */
+ builder, to their original states. */
restore_cleanups (old_catcher->saved_cleanup_chain);
- uiout = old_catcher->saved_uiout;
-
- quit_pre_print = old_catcher->saved_quit_pre_print;
- error_pre_print = old_catcher->saved_error_pre_print;
-
xfree (old_catcher);
}
/* Catcher state machine. Returns non-zero if the m/c should be run
again, zero if it should abort. */
-int
-catcher_state_machine (enum catcher_action action)
+static int
+exceptions_state_mc (enum catcher_action action)
{
switch (current_catcher->state)
{
current_catcher->state = CATCHER_RUNNING;
return 1;
default:
- internal_error (__FILE__, __LINE__, "bad state");
+ internal_error (__FILE__, __LINE__, _("bad state"));
}
case CATCHER_RUNNING:
switch (action)
/* See also throw_exception. */
return 1;
default:
- internal_error (__FILE__, __LINE__, "bad switch");
+ internal_error (__FILE__, __LINE__, _("bad switch"));
}
case CATCHER_RUNNING_1:
switch (action)
/* See also throw_exception. */
return 1;
default:
- internal_error (__FILE__, __LINE__, "bad switch");
+ internal_error (__FILE__, __LINE__, _("bad switch"));
}
case CATCHER_ABORTING:
switch (action)
{
case CATCH_ITER:
{
- struct exception exception = *current_catcher->exception;
+ struct gdb_exception exception = *current_catcher->exception;
+
if (current_catcher->mask & RETURN_MASK (exception.reason))
{
/* Exit normally if this catcher can handle this
}
/* The caller didn't request that the event be caught,
relay the event to the next containing
- catch_errors(). */
+ catch_errors(). */
catcher_pop ();
throw_exception (exception);
}
default:
- internal_error (__FILE__, __LINE__, "bad state");
+ internal_error (__FILE__, __LINE__, _("bad state"));
}
default:
- internal_error (__FILE__, __LINE__, "bad switch");
+ internal_error (__FILE__, __LINE__, _("bad switch"));
}
}
+int
+exceptions_state_mc_action_iter (void)
+{
+ return exceptions_state_mc (CATCH_ITER);
+}
+
+int
+exceptions_state_mc_action_iter_1 (void)
+{
+ return exceptions_state_mc (CATCH_ITER_1);
+}
+
/* Return EXCEPTION to the nearest containing catch_errors(). */
-NORETURN void
-throw_exception (struct exception exception)
+void
+throw_exception (struct gdb_exception exception)
{
- quit_flag = 0;
+ clear_quit_flag ();
immediate_quit = 0;
- /* Perhaps it would be cleaner to do this via the cleanup chain (not sure
- I can think of a reason why that is vital, though). */
- bpstat_clear_actions (stop_bpstat); /* Clear queued breakpoint commands */
-
- disable_current_display ();
- do_cleanups (ALL_CLEANUPS);
- if (target_can_async_p () && !target_executing)
- do_exec_cleanups (ALL_CLEANUPS);
- if (sync_execution)
- do_exec_error_cleanups (ALL_CLEANUPS);
-
- if (annotation_level > 1)
- switch (exception.reason)
- {
- case RETURN_QUIT:
- annotate_quit ();
- break;
- case RETURN_ERROR:
- /* Assume that these are all errors. */
- annotate_error ();
- break;
- default:
- internal_error (__FILE__, __LINE__, "Bad switch.");
- }
+ do_cleanups (all_cleanups ());
/* Jump to the containing catch_errors() call, communicating REASON
to that call via setjmp's return value. Note that REASON can't
- be zero, by definition in defs.h. */
- catcher_state_machine (CATCH_THROWING);
+ be zero, by definition in defs.h. */
+ exceptions_state_mc (CATCH_THROWING);
*current_catcher->exception = exception;
- SIGLONGJMP (current_catcher->buf, exception.reason);
+ EXCEPTIONS_SIGLONGJMP (current_catcher->buf, exception.reason);
}
-static char *last_message;
-
-NORETURN void
-throw_reason (enum return_reason reason)
+void
+deprecated_throw_reason (enum return_reason reason)
{
- struct exception exception;
+ struct gdb_exception exception;
+
memset (&exception, 0, sizeof exception);
exception.reason = reason;
break;
case RETURN_ERROR:
exception.error = GENERIC_ERROR;
- exception.message = last_message;
break;
default:
- internal_error (__FILE__, __LINE__, "bad switch");
+ internal_error (__FILE__, __LINE__, _("bad switch"));
}
throw_exception (exception);
static void
print_flush (void)
{
+ struct serial *gdb_stdout_serial;
+
if (deprecated_error_begin_hook)
deprecated_error_begin_hook ();
target_terminal_ours ();
- wrap_here (""); /* Force out any buffered output */
+
+ /* We want all output to appear now, before we print the error. We
+ have 3 levels of buffering we have to flush (it's possible that
+ some of these should be changed to flush the lower-level ones
+ too): */
+
+ /* 1. The _filtered buffer. */
+ wrap_here ("");
+
+ /* 2. The stdio buffer. */
gdb_flush (gdb_stdout);
+ gdb_flush (gdb_stderr);
+
+ /* 3. The system-level buffer. */
+ gdb_stdout_serial = serial_fdopen (1);
+ if (gdb_stdout_serial)
+ {
+ serial_drain_output (gdb_stdout_serial);
+ serial_un_fdopen (gdb_stdout_serial);
+ }
+
annotate_error_begin ();
}
static void
-print_exception (struct ui_file *file, struct exception e)
+print_exception (struct ui_file *file, struct gdb_exception e)
{
/* KLUGE: cagney/2005-01-13: Write the string out one line at a time
as that way the MI's behavior is preserved. */
const char *start;
const char *end;
+
for (start = e.message; start != NULL; start = end)
{
end = strchr (start, '\n');
}
}
fprintf_filtered (file, "\n");
+
+ /* Now append the annotation. */
+ switch (e.reason)
+ {
+ case RETURN_QUIT:
+ annotate_quit ();
+ break;
+ case RETURN_ERROR:
+ /* Assume that these are all errors. */
+ annotate_error ();
+ break;
+ default:
+ internal_error (__FILE__, __LINE__, _("Bad switch."));
+ }
}
void
-exception_print (struct ui_file *file, struct exception e)
+exception_print (struct ui_file *file, struct gdb_exception e)
{
if (e.reason < 0 && e.message != NULL)
{
}
void
-exception_fprintf (struct ui_file *file, struct exception e,
+exception_fprintf (struct ui_file *file, struct gdb_exception e,
const char *prefix, ...)
{
if (e.reason < 0 && e.message != NULL)
}
}
-NORETURN static void
-print_and_throw (enum return_reason reason, enum errors error,
- const char *prefix, const char *fmt,
- va_list ap) ATTR_NORETURN;
-NORETURN static void
-print_and_throw (enum return_reason reason, enum errors error,
- const char *prefix, const char *fmt, va_list ap)
+static void
+print_any_exception (struct ui_file *file, const char *prefix,
+ struct gdb_exception e)
{
- struct exception e;
+ if (e.reason < 0 && e.message != NULL)
+ {
+ target_terminal_ours ();
+ wrap_here (""); /* Force out any buffered output. */
+ gdb_flush (gdb_stdout);
+ annotate_error_begin ();
- /* Save the message. */
- xfree (last_message);
- last_message = xstrvprintf (fmt, ap);
+ /* Print the prefix. */
+ if (prefix != NULL && prefix[0] != '\0')
+ fputs_filtered (prefix, file);
+ print_exception (file, e);
+ }
+}
- /* Create the exception. */
- e.reason = reason;
- e.error = error;
- e.message = last_message;
+/* A stack of exception messages.
+ This is needed to handle nested calls to throw_it: we don't want to
+ xfree space for a message before it's used.
+ This can happen if we throw an exception during a cleanup:
+ An outer TRY_CATCH may have an exception message it wants to print,
+ but while doing cleanups further calls to throw_it are made.
+
+ This is indexed by the size of the current_catcher list.
+ It is a dynamically allocated array so that we don't care how deeply
+ GDB nests its TRY_CATCHs. */
+static char **exception_messages;
+
+/* The number of currently allocated entries in exception_messages. */
+static int exception_messages_size;
+
+static void ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (3, 0)
+throw_it (enum return_reason reason, enum errors error, const char *fmt,
+ va_list ap)
+{
+ struct gdb_exception e;
+ char *new_message;
+ int depth = catcher_list_size ();
+
+ gdb_assert (depth > 0);
+
+ /* Note: The new message may use an old message's text. */
+ new_message = xstrvprintf (fmt, ap);
- /* Print the mesage to stderr, but only if the catcher isn't going
- to handle/print it locally. */
- if (current_catcher->print_message)
+ if (depth > exception_messages_size)
{
- /* Write the message plus any pre_print to gdb_stderr. */
- print_flush ();
- if (error_pre_print)
- fputs_filtered (error_pre_print, gdb_stderr);
- print_exception (gdb_stderr, e);
+ int old_size = exception_messages_size;
+
+ exception_messages_size = depth + 10;
+ exception_messages = (char **) xrealloc (exception_messages,
+ exception_messages_size
+ * sizeof (char *));
+ memset (exception_messages + old_size, 0,
+ (exception_messages_size - old_size) * sizeof (char *));
}
+ xfree (exception_messages[depth - 1]);
+ exception_messages[depth - 1] = new_message;
+
+ /* Create the exception. */
+ e.reason = reason;
+ e.error = error;
+ e.message = new_message;
+
/* Throw the exception. */
throw_exception (e);
}
-NORETURN void
+void
throw_verror (enum errors error, const char *fmt, va_list ap)
{
- print_and_throw (RETURN_ERROR, error, error_pre_print, fmt, ap);
+ throw_it (RETURN_ERROR, error, fmt, ap);
}
-NORETURN void
+void
throw_vfatal (const char *fmt, va_list ap)
{
- print_and_throw (RETURN_QUIT, NO_ERROR, quit_pre_print, fmt, ap);
+ throw_it (RETURN_QUIT, GDB_NO_ERROR, fmt, ap);
}
-NORETURN void
+void
throw_error (enum errors error, const char *fmt, ...)
{
va_list args;
+
va_start (args, fmt);
- print_and_throw (RETURN_ERROR, error, error_pre_print, fmt, args);
+ throw_it (RETURN_ERROR, error, fmt, args);
va_end (args);
}
-/* Call FUNC() with args FUNC_UIOUT and FUNC_ARGS, catching any
- errors. Set FUNC_CAUGHT to an ``enum return_reason'' if the
- function is aborted (using throw_exception() or zero if the
- function returns normally. Set FUNC_VAL to the value returned by
- the function or 0 if the function was aborted.
+/* Call FUNC(UIOUT, FUNC_ARGS) but wrapped within an exception
+ handler. If an exception (enum return_reason) is thrown using
+ throw_exception() than all cleanups installed since
+ catch_exceptions() was entered are invoked, the (-ve) exception
+ value is then returned by catch_exceptions. If FUNC() returns
+ normally (with a positive or zero return value) then that value is
+ returned by catch_exceptions(). It is an internal_error() for
+ FUNC() to return a negative value.
+
+ See exceptions.h for further usage details.
Must not be called with immediate_quit in effect (bad things might
happen, say we got a signal in the middle of a memcpy to quit_return).
This is an OK restriction; with very few exceptions immediate_quit can
- be replaced by judicious use of QUIT.
-
- MASK specifies what to catch; it is normally set to
- RETURN_MASK_ALL, if for no other reason than that the code which
- calls catch_errors might not be set up to deal with a quit which
- isn't caught. But if the code can deal with it, it generally
- should be RETURN_MASK_ERROR, unless for some reason it is more
- useful to abort only the portion of the operation inside the
- catch_errors. Note that quit should return to the command line
- fairly quickly, even if some further processing is being done. */
+ be replaced by judicious use of QUIT. */
/* MAYBE: cagney/1999-11-05: catch_errors() in conjunction with
- error() et.al. could maintain a set of flags that indicate the the
+ error() et al. could maintain a set of flags that indicate the
current state of each of the longjmp buffers. This would give the
longjmp code the chance to detect a longjmp botch (before it gets
to longjmperror()). Prior to 1999-11-05 this wasn't possible as
code also randomly used a SET_TOP_LEVEL macro that directly
- initialize the longjmp buffers. */
-
-/* MAYBE: cagney/1999-11-05: Should the catch_errors and cleanups code
- be consolidated into a single file instead of being distributed
- between utils.c and top.c? */
+ initialized the longjmp buffers. */
int
catch_exceptions (struct ui_out *uiout,
return catch_exceptions_with_msg (uiout, func, func_args, NULL, mask);
}
-struct exception
-catch_exception (struct ui_out *uiout,
- catch_exception_ftype *func,
- void *func_args,
- return_mask mask)
-{
- volatile struct exception exception;
- SIGJMP_BUF *catch;
- catch = catcher_init (uiout, NULL, &exception, mask, 0);
- for (SIGSETJMP ((*catch));
- catcher_state_machine (CATCH_ITER);)
- (*func) (uiout, func_args);
- return exception;
-}
-
int
-catch_exceptions_with_msg (struct ui_out *uiout,
+catch_exceptions_with_msg (struct ui_out *func_uiout,
catch_exceptions_ftype *func,
void *func_args,
char **gdberrmsg,
return_mask mask)
{
- volatile struct exception exception;
+ volatile struct gdb_exception exception;
volatile int val = 0;
- SIGJMP_BUF *catch = catcher_init (uiout, NULL, &exception, mask, 1);
- for (SIGSETJMP ((*catch)); catcher_state_machine (CATCH_ITER);)
- val = (*func) (uiout, func_args);
+ struct ui_out *saved_uiout;
+
+ /* Save and override the global ``struct ui_out'' builder. */
+ saved_uiout = current_uiout;
+ current_uiout = func_uiout;
+
+ TRY_CATCH (exception, RETURN_MASK_ALL)
+ {
+ val = (*func) (current_uiout, func_args);
+ }
+
+ /* Restore the global builder. */
+ current_uiout = saved_uiout;
+
+ if (exception.reason < 0 && (mask & RETURN_MASK (exception.reason)) == 0)
+ {
+ /* The caller didn't request that the event be caught.
+ Rethrow. */
+ throw_exception (exception);
+ }
+
+ print_any_exception (gdb_stderr, NULL, exception);
gdb_assert (val >= 0);
gdb_assert (exception.reason <= 0);
if (exception.reason < 0)
return val;
}
+/* This function is superseded by catch_exceptions(). */
+
int
catch_errors (catch_errors_ftype *func, void *func_args, char *errstring,
return_mask mask)
{
volatile int val = 0;
- volatile struct exception exception;
- SIGJMP_BUF *catch = catcher_init (uiout, errstring, &exception, mask, 1);
- /* This illustrates how it is possible to nest the mechanism and
- hence catch "break". Of course this doesn't address the need to
- also catch "return". */
- for (SIGSETJMP ((*catch)); catcher_state_machine (CATCH_ITER);)
- val = func (func_args);
+ volatile struct gdb_exception exception;
+ struct ui_out *saved_uiout;
+
+ /* Save the global ``struct ui_out'' builder. */
+ saved_uiout = current_uiout;
+
+ TRY_CATCH (exception, RETURN_MASK_ALL)
+ {
+ val = func (func_args);
+ }
+
+ /* Restore the global builder. */
+ current_uiout = saved_uiout;
+
+ if (exception.reason < 0 && (mask & RETURN_MASK (exception.reason)) == 0)
+ {
+ /* The caller didn't request that the event be caught.
+ Rethrow. */
+ throw_exception (exception);
+ }
+
+ print_any_exception (gdb_stderr, errstring, exception);
if (exception.reason != 0)
return 0;
return val;
}
-struct captured_command_args
- {
- catch_command_errors_ftype *command;
- char *arg;
- int from_tty;
- };
-
-static int
-do_captured_command (void *data)
-{
- struct captured_command_args *context = data;
- context->command (context->arg, context->from_tty);
- /* FIXME: cagney/1999-11-07: Technically this do_cleanups() call
- isn't needed. Instead an assertion check could be made that
- simply confirmed that the called function correctly cleaned up
- after itself. Unfortunately, old code (prior to 1999-11-04) in
- main.c was calling SET_TOP_LEVEL(), calling the command function,
- and then *always* calling do_cleanups(). For the moment we
- remain ``bug compatible'' with that old code.. */
- do_cleanups (ALL_CLEANUPS);
- return 1;
-}
-
int
catch_command_errors (catch_command_errors_ftype * command,
char *arg, int from_tty, return_mask mask)
{
- struct captured_command_args args;
- args.command = command;
- args.arg = arg;
- args.from_tty = from_tty;
- return catch_errors (do_captured_command, &args, "", mask);
+ volatile struct gdb_exception e;
+
+ TRY_CATCH (e, mask)
+ {
+ command (arg, from_tty);
+ }
+ print_any_exception (gdb_stderr, NULL, e);
+ if (e.reason < 0)
+ return 0;
+ return 1;
}