binutils-gdb/gdbserver/utils.cc
Pedro Alves 171fba11ab Make GDBserver abort on internal error in development mode
Currently, if GDBserver hits some internal assertion, it exits with
error status, instead of aborting.  This makes it harder to debug
GDBserver, as you can't just debug a core file if GDBserver fails an
assertion.  I've had to hack the code to make GDBserver abort to debug
something several times before.

I believe the reason it exits instead of aborting, is to prevent
potentially littering the filesystem of smaller embedded targets with
core files.  I think I recall Daniel Jacobowitz once saying that many
years ago, but I can't be sure.  Anyhow, that seems reasonable to me.

Since we nowadays have a distinction between development and release
modes, I propose to make GDBserver abort on internal error if in
development mode, while keeping the status quo when in release mode.

Thus, after this patch, in development mode, you get:

 $ ../gdbserver/gdbserver
 ../../src/gdbserver/server.cc:3711: A problem internal to GDBserver has been detected.
 captured_main: Assertion `0' failed.
 Aborted (core dumped)
 $

while in release mode, you'll continue to get:

 $ ../gdbserver/gdbserver
 ../../src/gdbserver/server.cc:3711: A problem internal to GDBserver has been detected.
 captured_main: Assertion `0' failed.
 $ echo $?
 1

I do not think that this requires a separate configure switch.

A "--target_board=native-extended-gdbserver" run on Ubuntu 20.04 ends
up with:

		 === gdb Summary ===

 # of unexpected core files      29
 ...

for me, of which 8 are GDBserver core dumps, 7 more than without this
patch.

Change-Id: I6861e08ad71f65a0332c91ec95ca001d130b0e9d
2022-06-27 13:55:36 +01:00

130 lines
3.3 KiB
C++

/* General utility routines for the remote server for GDB.
Copyright (C) 1986-2022 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 "server.h"
#ifdef IN_PROCESS_AGENT
# define PREFIX "ipa: "
# define TOOLNAME "GDBserver in-process agent"
#else
# define PREFIX "gdbserver: "
# define TOOLNAME "GDBserver"
#endif
/* Generally useful subroutines used throughout the program. */
/* If in release mode, just exit. This avoids potentially littering
the filesystem of small embedded targets with core files. If in
development mode however, abort, producing core files to help with
debugging GDBserver. */
static void ATTRIBUTE_NORETURN
abort_or_exit ()
{
#ifdef DEVELOPMENT
abort ();
#else
exit (1);
#endif
}
void
malloc_failure (long size)
{
fprintf (stderr,
PREFIX "ran out of memory while trying to allocate %lu bytes\n",
(unsigned long) size);
abort_or_exit ();
}
/* Print the system error message for errno, and also mention STRING
as the file name for which the error was encountered.
Then return to command level. */
void
perror_with_name (const char *string)
{
const char *err;
char *combined;
err = safe_strerror (errno);
if (err == NULL)
err = "unknown error";
combined = (char *) alloca (strlen (err) + strlen (string) + 3);
strcpy (combined, string);
strcat (combined, ": ");
strcat (combined, err);
error ("%s.", combined);
}
/* Print an error message and return to top level. */
void
verror (const char *string, va_list args)
{
#ifdef IN_PROCESS_AGENT
fflush (stdout);
vfprintf (stderr, string, args);
fprintf (stderr, "\n");
exit (1);
#else
throw_verror (GENERIC_ERROR, string, args);
#endif
}
void
vwarning (const char *string, va_list args)
{
fprintf (stderr, PREFIX);
vfprintf (stderr, string, args);
fprintf (stderr, "\n");
}
/* Report a problem internal to GDBserver, and abort/exit. */
void
internal_verror (const char *file, int line, const char *fmt, va_list args)
{
fprintf (stderr, "\
%s:%d: A problem internal to " TOOLNAME " has been detected.\n", file, line);
vfprintf (stderr, fmt, args);
fprintf (stderr, "\n");
abort_or_exit ();
}
/* Report a problem internal to GDBserver. */
void
internal_vwarning (const char *file, int line, const char *fmt, va_list args)
{
fprintf (stderr, "\
%s:%d: A problem internal to " TOOLNAME " has been detected.\n", file, line);
vfprintf (stderr, fmt, args);
fprintf (stderr, "\n");
}
/* Convert a CORE_ADDR into a HEX string, like %lx.
The result is stored in a circular static buffer, NUMCELLS deep. */
char *
paddress (CORE_ADDR addr)
{
return phex_nz (addr, sizeof (CORE_ADDR));
}