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.
+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.
+
2016-01-12 Josh Stone <jistone@redhat.com>
Philippe Waroquiers <philippe.waroquiers@skynet.be>
error (_("No memory."));
/* Traceframes are effectively a substitute for the live inferior. */
if (get_traceframe_number () < 0)
- {
- if (ptid_equal (inferior_ptid, null_ptid))
- error (_("No selected thread."));
- if (is_exited (inferior_ptid))
- error (_("Invalid selected thread."));
- if (is_executing (inferior_ptid))
- error (_("Target is executing."));
- }
+ validate_registers_access ();
if (current_frame == NULL)
{
extern void thread_cancel_execution_command (struct thread_info *thr);
+/* Check whether it makes sense to access a register of the current
+ thread at this point. If not, throw an error (e.g., the thread is
+ executing). */
+extern void validate_registers_access (void);
+
extern struct thread_info *thread_list;
#endif /* GDBTHREAD_H */
"to change these tables.\n"));
}
-/* Check if it makes sense to read $_siginfo from the current thread
- at this point. If not, throw an error. */
-
-static void
-validate_siginfo_access (void)
-{
- /* No current inferior, no siginfo. */
- if (ptid_equal (inferior_ptid, null_ptid))
- error (_("No thread selected."));
-
- /* Don't try to read from a dead thread. */
- if (is_exited (inferior_ptid))
- error (_("The current thread has terminated"));
-
- /* ... or from a spinning thread. */
- if (is_running (inferior_ptid))
- error (_("Selected thread is running."));
-}
-
/* The $_siginfo convenience variable is a bit special. We don't know
for sure the type of the value until we actually have a chance to
fetch the data. The type can change depending on gdbarch, so it is
{
LONGEST transferred;
- validate_siginfo_access ();
+ /* If we can access registers, so can we access $_siginfo. Likewise
+ vice versa. */
+ validate_registers_access ();
transferred =
target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
{
LONGEST transferred;
- validate_siginfo_access ();
+ /* If we can access registers, so can we access $_siginfo. Likewise
+ vice versa. */
+ validate_registers_access ();
transferred = target_write (¤t_target,
TARGET_OBJECT_SIGNAL_INFO,
+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.
+
2016-01-12 Josh Stone <jistone@redhat.com>
Philippe Waroquiers <philippe.waroquiers@skynet.be>
--- /dev/null
+/* 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;
+}
--- /dev/null
+# 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/>.
+
+# Regression test for PR19388. Make sure we can access $_siginfo in a
+# "catch signal" condition. A buggy GDB would fail with:
+#
+# (gdb) continue
+# Continuing.
+# Error in testing breakpoint condition:
+# Selected thread is running.
+#
+# Catchpoint 3 (signal SIGUSR1), 0x0000003615e35877 in __GI_raise (sig=10) at raise.c:56
+# 56 return INLINE_SYSCALL (tgkill, 3, pid, selftid, sig);
+# (gdb) FAIL: gdb.base/catch-signal-siginfo-cond.exp: continue
+
+if [target_info exists gdb,nosignals] {
+ verbose "Skipping catch-signal-siginfo-cond.exp because of nosignals."
+ return -1
+}
+
+if { ![supports_get_siginfo_type] } {
+ verbose "Skipping catch-signal-siginfo-cond.exp because of lack of support."
+ return -1
+}
+
+standard_testfile
+
+if { [prepare_for_testing "failed to prepare" "${testfile}" $srcfile {debug}] } {
+ return -1
+}
+
+if ![runto_main] then {
+ fail "Can't run to main"
+ return -1
+}
+
+gdb_breakpoint [gdb_get_line_number "set breakpoint here"]
+
+gdb_test "catch signal"
+
+# It's OK to refer to standard Unix signal numbers 1-15 by number.
+
+# SIGUSR1 == 10. The catchpoint should not cause a stop.
+gdb_test "condition \$bpnum \$_siginfo.si_signo == 11"
+gdb_test "continue" "set breakpoint here.*" "continue: catchpoint does not trigger"
+
+# This time the catchpoint should cause a stop.
+gdb_test "condition \$bpnum \$_siginfo.si_signo == 10"
+gdb_test "continue" "Catchpoint .*signal SIGUSR1.*" "continue: catchpoint triggers"
finish_thread_state (*ptid_p);
}
+/* See gdbthread.h. */
+
+void
+validate_registers_access (void)
+{
+ /* No selected thread, no registers. */
+ if (ptid_equal (inferior_ptid, null_ptid))
+ error (_("No thread selected."));
+
+ /* Don't try to read from a dead thread. */
+ if (is_exited (inferior_ptid))
+ error (_("The current thread has terminated"));
+
+ /* ... or from a spinning thread. FIXME: This isn't actually fully
+ correct. It'll allow an user-requested access (e.g., "print $pc"
+ at the prompt) when a thread is not executing for some internal
+ reason, but is marked running from the user's perspective. E.g.,
+ the thread is waiting for its turn in the step-over queue. */
+ if (is_executing (inferior_ptid))
+ error (_("Selected thread is running."));
+}
+
int
pc_in_thread_step_range (CORE_ADDR pc, struct thread_info *thread)
{
projects / deliverable / binutils-gdb.git / commitdiff
