Re: [patch] Do not disappoint on "Create a core file of GDB?"

Jan Kratochvil
2010-01-11T16:18:18Z

On Mon, 11 Jan 2010 17:07:30 +0100, Tristan Gingold wrote:
>
> On Jan 11, 2010, at 5:02 PM, Jan Kratochvil wrote:
> Hi,
>
> sorry for the nit but:
>
> > setrlimit is a POSIX function so I hope it does not need autoconf magic:
> > http://www.opengroup.org/onlinepubs/009695399/functions/setrlimit.html
>
> Sure, but windows is not POSIX compliant, so I think you can't avoid some
> autoconf stuff.

OK.

The patch has now no effect on platforms without setrlimit / getrlimit.

Thanks,
Jan

2010-01-11 Jan Kratochvil <jan.kratochvil@redhat.com>

* configure.ac (AC_CHECK_FUNCS): Check for setrlimit and getrlimit.
* configure: Regenerate.
* config.in: Regenerate.
* utils.c: Include sys/resource.h.
(dump_core, can_dump_core): New.
(internal_vproblem): Update the comment. Check can_dump_core while
setting dump_core_p. Replace two abort calls by dump_core calls.

--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -801,7 +801,8 @@ AC_FUNC_VFORK
AC_CHECK_FUNCS([canonicalize_file_name realpath getrusage getuid \
getgid pipe poll pread64 sbrk setpgid setpgrp setsid \
sigaction sigprocmask sigsetmask socketpair syscall \
- ttrace wborder setlocale iconvlist libiconvlist btowc])
+ ttrace wborder setlocale iconvlist libiconvlist btowc \
+ setrlimit getrlimit])
AM_LANGINFO_CODESET

# Check the return and argument types of ptrace. No canned test for
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -26,6 +26,9 @@
#include "event-top.h"
#include "exceptions.h"
#include "gdbthread.h"
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif /* HAVE_SYS_RESOURCE_H */

#ifdef TUI
#include "tui/tui.h" /* For tui_get_command_dimension. */
@@ -843,6 +844,44 @@ error_stream (struct ui_file *stream)
error (("%s"), message);
}

+/* Dump core trying to increase the core soft limit to hard limit first. */
+
+static void
+dump_core (void)
+{
+#ifdef HAVE_SETRLIMIT
+ struct rlimit rlim = { RLIM_INFINITY, RLIM_INFINITY };
+
+ setrlimit (RLIMIT_CORE, &rlim);
+#endif /* HAVE_SETRLIMIT */
+
+ abort (); /* NOTE: GDB has only three calls to abort(). */
+}
+
+/* Check whether GDB will be able to dump core using the dump_core function. */
+
+static int
+can_dump_core (const char *reason)
+{
+#ifdef HAVE_GETRLIMIT
+ struct rlimit rlim;
+
+ /* Be quiet and assume we can dump if an error is returned. */
+ if (getrlimit (RLIMIT_CORE, &rlim) != 0)
+ return 1;
+
+ if (rlim.rlim_max == 0)
+ {
+ fprintf_unfiltered (gdb_stderr,
+ _("%s\nUnable to dump core, use `ulimit -c unlimited'"
+ " before executing GDB next time.\n"), reason);
+ return 0;
+ }
+#endif /* HAVE_GETRLIMIT */
+
+ return 1;
+}
+
/* Allow the user to configure the debugger behavior with respect to
what to do when an internal problem is detected. */

@@ -893,7 +932,7 @@ internal_vproblem (struct internal_problem *problem,
case 1:
dejavu = 2;
fputs_unfiltered (msg, gdb_stderr);
- abort (); /* NOTE: GDB has only four calls to abort(). */
+ abort (); /* NOTE: GDB has only three calls to abort(). */
default:
dejavu = 3;
/* Newer GLIBC versions put the warn_unused_result attribute
@@ -902,7 +941,7 @@ internal_vproblem (struct internal_problem *problem,
does not fix this problem. This is the solution suggested
at http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25509. */
if (write (STDERR_FILENO, msg, sizeof (msg)) != sizeof (msg))
- abort (); /* NOTE: GDB has only four calls to abort(). */
+ abort (); /* NOTE: GDB has only three calls to abort(). */
exit (1);
}
}
@@ -951,13 +990,18 @@ further debugging may prove unreliable.", file, line, problem->name, msg);

if (problem->should_dump_core == internal_problem_ask)
{
- /* Default (yes/batch case) is to dump core. This leaves a GDB
- `dropping' so that it is easier to see that something went
- wrong in GDB. */
- dump_core_p = query (_("%s\nCreate a core file of GDB? "), reason);
+ if (!can_dump_core (reason))
+ dump_core_p = 0;
+ else
+ {
+ /* Default (yes/batch case) is to dump core. This leaves a GDB
+ `dropping' so that it is easier to see that something went
+ wrong in GDB. */
+ dump_core_p = query (_("%s\nCreate a core file of GDB? "), reason);
+ }
}
else if (problem->should_dump_core == internal_problem_yes)
- dump_core_p = 1;
+ dump_core_p = can_dump_core (reason);
else if (problem->should_dump_core == internal_problem_no)
dump_core_p = 0;
else
@@ -966,7 +1010,7 @@ further debugging may prove unreliable.", file, line, problem->name, msg);
if (quit_p)
{
if (dump_core_p)
- abort (); /* NOTE: GDB has only four calls to abort(). */
+ dump_core ();
else
exit (1);
}
@@ -976,7 +1020,7 @@ further debugging may prove unreliable.", file, line, problem->name, msg);
{
#ifdef HAVE_WORKING_FORK
if (fork () == 0)
- abort (); /* NOTE: GDB has only four calls to abort(). */
+ dump_core ();
#endif
}
}