diff options
author | Pedro Alves <palves@redhat.com> | 2016-01-13 10:40:33 +0000 |
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committer | Pedro Alves <palves@redhat.com> | 2016-01-13 10:40:33 +0000 |
commit | a911d87ad714cbfbbc5c5752cb8b445a7e70196c (patch) | |
tree | f7a48df5a040748238538d62ea9c2b0f51f41a43 /gdb/testsuite/gdb.base/catch-signal-siginfo-cond.c | |
parent | 8405419985b2a5f9c4f79b28af6c2324655b5c5b (diff) |
Fix PR19388: Can't access $_siginfo in breakpoint (catch signal) condition
This commit merges both the registers and $_siginfo "thread
running/executing" checks into a single function.
Accessing $_siginfo from a "catch signal" breakpoint condition doesn't
work. The condition always fails with "Selected thread is running":
(gdb) catch signal
Catchpoint 3 (standard signals)
(gdb)
condition $bpnum $_siginfo.si_signo == 5
(gdb) continue
Continuing.
Error in testing breakpoint condition:
Selected thread is running.
Catchpoint 3 (signal SIGUSR1), 0x0000003615e35877 in __GI_raise (sig=10) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
56 return INLINE_SYSCALL (tgkill, 3, pid, selftid, sig);
(gdb)
When accessing the $_siginfo object, we check whether the thread is
marked running (external/public) state and refuse the access if so.
This is so "print $_siginfo" at the prompt fails nicelly when the
current thread is running. While evaluating breakpoint conditionals,
we haven't decided yet whether the thread is going to stop, so
is_running still returns true, and we thus always error out.
Evaluating an expression that requires registers access is really
conceptually the same -- we could think of $_siginfo as a pseudo
register. However, in that case we check whether the thread is marked
executing (internal/private state), not running (external/public
state). Changing the $_siginfo validation to check is_executing as
well fixes the bug in question.
Note that checking is_executing is not fully correct, not even for
registers. See PR 19389. However, I think this is the lesser of two
evils and ends up as an improvement. We at least now have a single
place to fix.
Tested on x86_64 GNU/Linux.
gdb/ChangeLog:
2016-01-13 Pedro Alves <palves@redhat.com>
PR breakpoints/19388
* frame.c (get_current_frame): Use validate_registers_access.
* gdbthread.h (validate_registers_access): Declare.
* infrun.c (validate_siginfo_access): Delete.
(siginfo_value_read, siginfo_value_write): Use
validate_registers_access.
* thread.c (validate_registers_access): New function.
gdb/testsuite/ChangeLog:
2016-01-13 Pedro Alves <palves@redhat.com>
PR breakpoints/19388
* gdb.base/catch-signal-siginfo-cond.c: New file.
* gdb.base/catch-signal-siginfo-cond.exp: New file.
Diffstat (limited to 'gdb/testsuite/gdb.base/catch-signal-siginfo-cond.c')
-rw-r--r-- | gdb/testsuite/gdb.base/catch-signal-siginfo-cond.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/gdb/testsuite/gdb.base/catch-signal-siginfo-cond.c b/gdb/testsuite/gdb.base/catch-signal-siginfo-cond.c new file mode 100644 index 0000000000..3a9ee3d64b --- /dev/null +++ b/gdb/testsuite/gdb.base/catch-signal-siginfo-cond.c @@ -0,0 +1,33 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2015-2016 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/>. */ + +#include <signal.h> +#include <unistd.h> + +void +handle (int sig) +{ +} + +int +main (void) +{ + signal (SIGUSR1, handle); + raise (SIGUSR1); + raise (SIGUSR1); /* set breakpoint here */ + return 0; +} |