binutils-gdb/gdb/exceptions.c

277 lines
7.0 KiB
C

/* Exception (throw catch) mechanism, for GDB, the GNU debugger.
Copyright (C) 1986-2016 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 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "exceptions.h"
#include "breakpoint.h"
#include "target.h"
#include "inferior.h"
#include "annotate.h"
#include "ui-out.h"
#include "serial.h"
#include "gdbthread.h"
#include "top.h"
static void
print_flush (void)
{
struct ui *ui = current_ui;
struct serial *gdb_stdout_serial;
struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
if (deprecated_error_begin_hook)
deprecated_error_begin_hook ();
if (target_supports_terminal_ours ())
{
make_cleanup_restore_target_terminal ();
target_terminal_ours_for_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. */
if (filtered_printing_initialized ())
wrap_here ("");
/* 2. The stdio buffer. */
gdb_flush (gdb_stdout);
gdb_flush (gdb_stderr);
/* 3. The system-level buffer. */
gdb_stdout_serial = serial_fdopen (fileno (ui->outstream));
if (gdb_stdout_serial)
{
serial_drain_output (gdb_stdout_serial);
serial_un_fdopen (gdb_stdout_serial);
}
annotate_error_begin ();
do_cleanups (old_chain);
}
static void
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');
if (end == NULL)
fputs_filtered (start, file);
else
{
end++;
ui_file_write (file, start, end - start);
}
}
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 gdb_exception e)
{
if (e.reason < 0 && e.message != NULL)
{
print_flush ();
print_exception (file, e);
}
}
void
exception_fprintf (struct ui_file *file, struct gdb_exception e,
const char *prefix, ...)
{
if (e.reason < 0 && e.message != NULL)
{
va_list args;
print_flush ();
/* Print the prefix. */
va_start (args, prefix);
vfprintf_filtered (file, prefix, args);
va_end (args);
print_exception (file, e);
}
}
/* 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. */
/* MAYBE: cagney/1999-11-05: catch_errors() in conjunction with
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
initialized the longjmp buffers. */
int
catch_exceptions (struct ui_out *uiout,
catch_exceptions_ftype *func,
void *func_args,
return_mask mask)
{
return catch_exceptions_with_msg (uiout, func, func_args, NULL, mask);
}
int
catch_exceptions_with_msg (struct ui_out *func_uiout,
catch_exceptions_ftype *func,
void *func_args,
char **gdberrmsg,
return_mask mask)
{
struct gdb_exception exception = exception_none;
volatile int val = 0;
struct ui_out *saved_uiout;
/* Save and override the global ``struct ui_out'' builder. */
saved_uiout = current_uiout;
current_uiout = func_uiout;
TRY
{
val = (*func) (current_uiout, func_args);
}
CATCH (ex, RETURN_MASK_ALL)
{
exception = ex;
}
END_CATCH
/* 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);
}
exception_print (gdb_stderr, exception);
gdb_assert (val >= 0);
gdb_assert (exception.reason <= 0);
if (exception.reason < 0)
{
/* If caller wants a copy of the low-level error message, make
one. This is used in the case of a silent error whereby the
caller may optionally want to issue the message. */
if (gdberrmsg != NULL)
{
if (exception.message != NULL)
*gdberrmsg = xstrdup (exception.message);
else
*gdberrmsg = NULL;
}
return exception.reason;
}
return val;
}
/* This function is superseded by catch_exceptions(). */
int
catch_errors (catch_errors_ftype *func, void *func_args, char *errstring,
return_mask mask)
{
struct gdb_exception exception = exception_none;
volatile int val = 0;
struct ui_out *saved_uiout;
/* Save the global ``struct ui_out'' builder. */
saved_uiout = current_uiout;
TRY
{
val = func (func_args);
}
CATCH (ex, RETURN_MASK_ALL)
{
exception = ex;
}
END_CATCH
/* 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);
}
exception_fprintf (gdb_stderr, exception, "%s", errstring);
if (exception.reason != 0)
return 0;
return val;
}
/* See exceptions.h. */
int
exception_print_same (struct gdb_exception e1, struct gdb_exception e2)
{
const char *msg1 = e1.message;
const char *msg2 = e2.message;
if (msg1 == NULL)
msg1 = "";
if (msg2 == NULL)
msg2 = "";
return (e1.reason == e2.reason
&& e1.error == e2.error
&& strcmp (msg1, msg2) == 0);
}