Have SIGTERM promptly quit GDB even when the dummy target is active

GDB currently does not promptly quit after receiving a SIGTERM while no
proper target is active.  This is because in handle_sigterm we currently
look at target_can_async_p to determine whether to asynchronously quit
GDB using an async signal handler or to asynchronously quit using the
quit flag.  However, target_can_async_p is always false under the dummy
target, so under this target we always use the quit flag and not the
async signal handler to signal that GDB should quit.  So GDB won't quit
until a code path that checks the quit flag is executed.

To fix this issue, this patch makes the SIGTERM handler no longer
inspect target_can_async_p, and instead makes the handler
unconditionally set the quit flag _and_ mark the corresponding async
signal handler, so that if the target is async (or if it's the dummy
target) then we will likely quit through the async signal handler, and
if it's not async then we will likely quit through the quit flag.  This
redundant approach is similar to how we handle SIGINT.

gdb/ChangeLog:

	* event-top.c (handle_sigterm): Don't inspect
	target_can_async_p.  Always set the quit flag and always mark
	the async signal handler.

gdb/testsuite/ChangeLog:

	* gdb.base/gdb-sigterm-2.exp: New test.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a6e993eae451ed2efcf40c658171085deba9bf1c..a03ca355f833d1da1f86b93145d01102a8e6c20a 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,9 @@
+2015-07-27  Patrick Palka  <patrick@parcs.ath.cx>
+
+       * event-top.c (handle_sigterm): Don't inspect
+       target_can_async_p.  Always set the quit flag and always mark
+       the async signal handler.
+
 2015-07-27  Yao Qi  <yao.qi@linaro.org>
 
        * Makefile.in (REMOTE_EXAMPLES): Remove it.

diff --git a/gdb/event-top.c b/gdb/event-top.c
index e9cc2d7d3e174c512fe32c6f8f08c0b49002a048..1762e3bd8e1948942fa2f959a309dc3acc3b3bcb 100644 (file)
--- a/gdb/event-top.c
+++ b/gdb/event-top.c
@@ -876,15 +876,10 @@ handle_sigterm (int sig)
 {
   signal (sig, handle_sigterm);
 
-  /* Call quit_force in a signal safe way.
-     quit_force itself is not signal safe.  */
-  if (target_can_async_p ())
-    mark_async_signal_handler (async_sigterm_token);
-  else
-    {
-      sync_quit_force_run = 1;
-      set_quit_flag ();
-    }
+  sync_quit_force_run = 1;
+  set_quit_flag ();
+
+  mark_async_signal_handler (async_sigterm_token);
 }
 
 /* Do the quit.  All the checks have been done by the caller.  */

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 1faf1ab62c7f80ddf4b6f05f82e40cf38a86aef2..818ea30d3b7407ffff5e789fe7d3b7dcf36eed80 100644 (file)
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2015-07-27  Patrick Palka  <patrick@parcs.ath.cx>
+
+       * gdb.base/gdb-sigterm-2.exp: New test.
+
 2015-07-25  Doug Evans  <xdje42@gmail.com>
 
        Revert:

diff --git a/gdb/testsuite/gdb.base/gdb-sigterm-2.exp b/gdb/testsuite/gdb.base/gdb-sigterm-2.exp
new file mode 100644 (file)
index 0000000..e2121a4
--- /dev/null
+++ b/gdb/testsuite/gdb.base/gdb-sigterm-2.exp
@@ -0,0 +1,32 @@
+# This testcase is part of GDB, the GNU debugger.
+#
+# Copyright 2015 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/>.
+
+# Check that GDB promptly quits after receiving a SIGTERM while no proper
+# target is active.
+
+gdb_start
+
+set gdb_pid [exp_pid -i [board_info host fileid]]
+remote_exec host "kill -TERM $gdb_pid"
+
+set test "expect eof"
+gdb_test_multiple "" $test {
+    -timeout 5
+    eof {
+       pass $test
+    }
+}