darkkirb/old-cross-binutils
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

This patch adds a new convenience variable called "$_exitsignal", which

Browse source 
will hold the signal number when the inferior terminates due to the
uncaught signal.

I've made modifications on infrun.c:handle_inferior_event such that
$_exitcode gets cleared when the inferior signalled, and vice-versa.
This assumption was made because the variables are mutually
exclusive, i.e., when the inferior terminates because of an uncaught
signal it is not possible for it to return.  I have also made modifications
such that when a corefile is loaded, $_exitsignal gets set to the uncaught
signal that "killed" the inferior, and $_exitcode is cleared.

The patch also adds a NEWS entry, documentation bits, and a testcase.  The
documentation entry explains how to use $_exitsignal and $_exitcode in a
GDB script, by making use of the new $_isvoid convenience function.

gdb/
2013-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>

	* NEWS: Mention new convenience variable $_exitsignal.
	* corelow.c (core_open): Reset exit convenience variables.  Set
	$_exitsignal to the uncaught signal which generated the corefile.
	* infrun.c (handle_inferior_event): Reset exit convenience
	variables.  Set $_exitsignal for TARGET_WAITKIND_SIGNALLED.
	(clear_exit_convenience_vars): New function.
	* inferior.h (clear_exit_convenience_vars): New prototype.

gdb/testsuite/
2013-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>

	* gdb.base/corefile.exp: Test whether $_exitsignal is set and
	$_exitcode is void when opening a corefile.
	* gdb.base/exitsignal.exp: New file.
	* gdb.base/segv.c: Likewise.
	* gdb.base/normal.c: Likewise.

gdb/doc/
2013-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>

	* gdb.texinfo (Convenience Variables): Document $_exitsignal.
	Update entry for $_exitcode.
This commit is contained in:
Sergio Durigan Junior 2013-10-07 05:34:11 +00:00
parent f872dc3d6e
commit 0c5571793a
12 changed files with 308 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
gdb/ChangeLog
View file

@ -1,3 +1,13 @@
2013-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* NEWS: Mention new convenience variable $_exitsignal.
* corelow.c (core_open): Reset exit convenience variables. Set
$_exitsignal to the uncaught signal which generated the corefile.
* infrun.c (handle_inferior_event): Reset exit convenience
variables. Set $_exitsignal for TARGET_WAITKIND_SIGNALLED.
(clear_exit_convenience_vars): New function.
* inferior.h (clear_exit_convenience_vars): New prototype.
2013-10-06 Yao Qi <yao@codesourcery.com>
* varobj.h: Add comments to enum varobj_languages.

4
gdb/NEWS
View file

@ -122,6 +122,10 @@ show range-stepping
* The exception-related catchpoints, like "catch throw", now accept a
regular expression which can be used to filter exceptions by type.
* The new convenience variable $_exitsignal is automatically set to
the terminating signal number when the program being debugged dies
due to an uncaught signal.
* MI changes
** The -trace-save MI command can optionally save trace buffer in Common

8
gdb/corelow.c
View file

@ -429,6 +429,9 @@ core_open (char *filename, int from_tty)
if (p)
printf_filtered (_("Core was generated by `%s'.\n"), p);
/* Clearing any previous state of convenience variables. */
clear_exit_convenience_vars ();
siggy = bfd_core_file_failing_signal (core_bfd);
if (siggy > 0)
{
@ -446,6 +449,11 @@ core_open (char *filename, int from_tty)
printf_filtered (_("Program terminated with signal %s, %s.\n"),
gdb_signal_to_name (sig), gdb_signal_to_string (sig));
/* Set the value of the internal variable $_exitsignal,
which holds the signal uncaught by the inferior. */
set_internalvar_integer (lookup_internalvar ("_exitsignal"),
siggy);
}
/* Fetch all registers from core file. */

5
gdb/doc/ChangeLog
View file

@ -1,3 +1,8 @@
2013-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.texinfo (Convenience Variables): Document $_exitsignal.
Update entry for $_exitcode.
2013-10-04 Joel Brobecker <brobecker@adacore.com>
* gdb.texinfo (GDB/MI Program Execution): Document "-exec-run"'s

60
gdb/doc/gdb.texinfo
View file

@ -9751,8 +9751,64 @@ to match the format in which the data was printed.
@item $_exitcode
@vindex $_exitcode@r{, convenience variable}
The variable @code{$_exitcode} is automatically set to the exit code when
the program being debugged terminates.
When the program being debugged terminates normally, @value{GDBN}
automatically sets this variable to the exit code of the program, and
resets @code{$_exitsignal} to @code{void}.
@item $_exitsignal
@vindex $_exitsignal@r{, convenience variable}
When the program being debugged dies due to an uncaught signal,
@value{GDBN} automatically sets this variable to that signal's number,
and resets @code{$_exitcode} to @code{void}.
To distinguish between whether the program being debugged has exited
(i.e., @code{$_exitcode} is not @code{void}) or signalled (i.e.,
@code{$_exitsignal} is not @code{void}), the convenience function
@code{$_isvoid} can be used (@pxref{Convenience Funs,, Convenience
Functions}). For example, considering the following source code:
@smallexample
#include <signal.h>
int
main (int argc, char *argv[])
@{
raise (SIGALRM);
return 0;
@}
@end smallexample
A valid way of telling whether the program being debugged has exited
or signalled would be:
@smallexample
(@value{GDBP}) define has_exited_or_signalled
Type commands for definition of ``has_exited_or_signalled''.
End with a line saying just ``end''.
>if $_isvoid ($_exitsignal)
>echo The program has exited\n
>else
>echo The program has signalled\n
>end
>end
(@value{GDBP}) run
Starting program:
Program terminated with signal SIGALRM, Alarm clock.
The program no longer exists.
(@value{GDBP}) has_exited_or_signalled
The program has signalled
@end smallexample
As can be seen, @value{GDBN} correctly informs that the program being
debugged has signalled, since it calls @code{raise} and raises a
@code{SIGALRM} signal. If the program being debugged had not called
@code{raise}, then @value{GDBN} would report a normal exit:
@smallexample
(@value{GDBP}) has_exited_or_signalled
The program has exited
@end smallexample
@item $_exception
The variable @code{$_exception} is set to the exception object being

6
gdb/inferior.h
View file

@ -224,6 +224,12 @@ extern void follow_inferior_reset_breakpoints (void);
void set_step_info (struct frame_info *frame, struct symtab_and_line sal);
/* Clear the convenience variables associated with the exit of the
inferior. Currently, those variables are $_exitcode and
$_exitsignal. */
extern void clear_exit_convenience_vars (void);
/* From infcmd.c */
extern void post_create_inferior (struct target_ops *, int);

41
gdb/infrun.c
View file

@ -3426,6 +3426,9 @@ handle_inferior_event (struct execution_control_state *ecs)
handle_vfork_child_exec_or_exit (0);
target_terminal_ours (); /* Must do this before mourn anyway. */
/* Clearing any previous state of convenience variables. */
clear_exit_convenience_vars ();
if (ecs->ws.kind == TARGET_WAITKIND_EXITED)
{
/* Record the exit code in the convenience variable $_exitcode, so
@ -3440,7 +3443,34 @@ handle_inferior_event (struct execution_control_state *ecs)
print_exited_reason (ecs->ws.value.integer);
}
else
print_signal_exited_reason (ecs->ws.value.sig);
{
struct regcache *regcache = get_thread_regcache (ecs->ptid);
struct gdbarch *gdbarch = get_regcache_arch (regcache);
if (gdbarch_gdb_signal_to_target_p (gdbarch))
{
/* Set the value of the internal variable $_exitsignal,
which holds the signal uncaught by the inferior. */
set_internalvar_integer (lookup_internalvar ("_exitsignal"),
gdbarch_gdb_signal_to_target (gdbarch,
ecs->ws.value.sig));
}
else
{
/* We don't have access to the target's method used for
converting between signal numbers (GDB's internal
representation <-> target's representation).
Therefore, we cannot do a good job at displaying this
information to the user. It's better to just warn
her about it (if infrun debugging is enabled), and
give up. */
if (debug_infrun)
fprintf_filtered (gdb_stdlog, _("\
Cannot fill $_exitsignal with the correct signal number.\n"));
}
print_signal_exited_reason (ecs->ws.value.sig);
}
gdb_flush (gdb_stdout);
target_mourn_inferior ();
@ -7061,6 +7091,15 @@ save_inferior_ptid (void)
*saved_ptid_ptr = inferior_ptid;
return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
}
/* See inferior.h. */
void
clear_exit_convenience_vars (void)
{
clear_internalvar (lookup_internalvar ("_exitsignal"));
clear_internalvar (lookup_internalvar ("_exitcode"));
}
/* User interface for reverse debugging:

8
gdb/testsuite/ChangeLog
View file

@ -1,3 +1,11 @@
2013-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.base/corefile.exp: Test whether $_exitsignal is set and
$_exitcode is void when opening a corefile.
* gdb.base/exitsignal.exp: New file.
* gdb.base/segv.c: Likewise.
* gdb.base/normal.c: Likewise.
2013-10-04 Joel Brobecker <brobecker@adacore.com>
* gdb.mi/mi-start.c, gdb.mi/mi-start.exp: New files.

10
gdb/testsuite/gdb.base/corefile.exp
View file

@ -142,6 +142,16 @@ gdb_test "print coremaker_ro" "\\\$$decimal = 201"
gdb_test "print func2::coremaker_local" "\\\$$decimal = \\{0, 1, 2, 3, 4\\}"
# Test the presence and the correct values of $_exitsignal and
# $_exitcode variables. The corefile is generated with a SIGABRT,
# which is "6" in the Linux kernel.
gdb_test "print \$_exitsignal" " = 6" \
"\$_exitsignal prints SIGABRT (6)"
gdb_test "print \$_exitcode" " = void" \
"\$_exitcode is void"
# Somehow we better test the ability to read the registers out of the core
# file correctly. I don't think the other tests do this.

106
gdb/testsuite/gdb.base/exitsignal.exp Normal file
View file

@ -0,0 +1,106 @@
# Copyright 2013 Free Software Foundation, Inc.
# 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/>.
# This test checks both $_exitcode and $_exitsignal variables. The
# purpose of this checking is to ensure that the variables are
# mutually exclusive, i.e., that when $_exitsignal is set, $_exitcode
# is not, and vice-versa. This mutual exclusion happens because if an
# inferior exited (either successfuly or not), it certainly was not
# killed by a signal. However, if it was killed by an uncaught
# signal, then there is no way for it to have exited.
if { [target_info exists gdb,nosignals] } {
verbose "Skipping exitsignal.exp because of nosignals."
continue
}
standard_testfile segv.c
if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } {
return -1
}
# Run to main
if { ![runto_main] } {
return -1
}
# Print $_exitsignal. It should be void now, because nothing
# happened.
gdb_test "print \$_exitsignal" " = void" \
"\$_exitsignal is void before running"
# Just to guarantee, making sure that $_exitcode is also void.
gdb_test "print \$_exitcode" " = void" \
"\$_exitcode is void before running"
# Trigger SIGSEGV.
gdb_test "continue" "Program received signal SIGSEGV.*" "trigger SIGSEGV"
# Continue until the end.
gdb_test "continue" "Program terminated with signal SIGSEGV.*" \
"program terminated with SIGSEGV"
# Now, print $_exitsignal again. It should be 11 (SIGSEGV).
gdb_test "print \$_exitsignal" " = 11" \
"\$_exitsignal is 11 (SIGSEGV) after SIGSEGV."
# And $_exitcode should still be void, since the inferior died because
# of a signal, and did not return.
gdb_test "print \$_exitcode" " = void" \
"\$_exitcode is still void after SIGSEGV"
# Re-run to main, i.e., restart the executable.
rerun_to_main
# Print the $_exitsignal again. Even in this normal scenario, it
# should still contain the signal triggered in the other run.
gdb_test "print \$_exitsignal" " = 11" \
"\$_exitsignal is 11 (SIGSEGV) after restarting the inferior"
# And, again, print $_exitcode.
gdb_test "print \$_exitcode" " = void" \
"\$_exitcode is still void after restarting the inferior"
# Now we test the behaviour of $_exit{code,signal} during a normal
# inferior execution.
standard_testfile normal.c
if { [prepare_for_testing ${testfile}.exp ${testfile} ${srcfile}] } {
return -1
}
# Checking $_exitsignal and $_exitcode, both should be void before the
# inferior is executed.
gdb_test "print \$_exitsignal" " = void" \
"\$_exitsignal is void before normal inferior is executed"
gdb_test "print \$_exitcode" " = void" \
"\$_exitcode is void before normal inferior is executed"
# Run the inferior until the end.
if { ![runto_main] } {
return -1
}
gdb_continue_to_end
# Checking $_exitcode. It should be 0.
gdb_test "print \$_exitcode" " = 0" \
"\$_exitcode is zero after normal inferior is executed"
# Checking $_exitsignal. It should still be void, since the inferior
# has not received any signal.
gdb_test "print \$_exitsignal" " = void" \
"\$_exitsignal is still void after normal inferior is executed"

24
gdb/testsuite/gdb.base/normal.c Normal file
View file

@ -0,0 +1,24 @@
/* This testcase is part of GDB, the GNU debugger.
Copyright 2013 Free Software Foundation, Inc.
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/>. */
/* This test is just a normal return 0. */
int
main (int argc, char *argv[])
{
return 0;
}

29
gdb/testsuite/gdb.base/segv.c Normal file
View file

@ -0,0 +1,29 @@
/* This testcase is part of GDB, the GNU debugger.
Copyright 2013 Free Software Foundation, Inc.
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/>. */
/* This test can be used just to generate a SIGSEGV. */
#include <signal.h>
int
main (int argc, char *argv[])
{
/* Generating a SIGSEGV. */
raise (SIGSEGV);
return 0;
}