New test case gdb.trace/signal.exp

This is to test whether GDBserver deliver signal to the inferior while
doing the step over.  Nowadays, GDBserver doesn't deliver signal, so
there won't be spurious collection, however, if GDBserver does deliver
signal, there might be spurious collection.

gdb/testsuite:

2016-04-22  Yao Qi  <yao.qi@linaro.org>

	* gdb.trace/signal.c: New file.
	* gdb.trace/signal.exp: New file.

1 files changed, 68 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.trace/signal.c b/gdb/testsuite/gdb.trace/signal.c
new file mode 100644
index 0000000..4577a7b
--- /dev/null
+++ b/gdb/testsuite/gdb.trace/signal.c
@@ -0,0 +1,68 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 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 <string.h>
+#include <unistd.h>
+
+static int counter = 0;
+
+static void
+handler (int sig)
+{
+  counter++;
+}
+
+static int iterations = 3;
+
+static void
+start (int pid)
+{
+  int i;
+
+  for (i = 0; i < iterations; i++)
+    {
+      kill (pid, SIGABRT);
+    }
+}
+
+static void
+end (void)
+{}
+
+int
+main (void)
+{
+  struct sigaction act;
+  int i;
+
+  memset (&act, 0, sizeof act);
+  act.sa_handler = handler;
+  act.sa_flags = SA_NODEFER;
+  sigaction (SIGABRT, &act, NULL);
+
+  for (i = 0; i < 3; i++)
+    {
+      kill (getpid (), SIGABRT);
+    }
+
+  counter = 0;
+  start (getpid ());
+
+  end ();
+  return 0;
+}