Merge GDB 7.5.1

gdb/testsuite/gdb.threads/watchpoint-fork-child.c

+/* Test case for forgotten hw-watchpoints after fork()-off of a process.
+
+   Copyright 2012 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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 2 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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <assert.h>
+#include <signal.h>
+#include <stdio.h>
+
+#include "watchpoint-fork.h"
+
+/* `pid_t' may not be available.  */
+
+static volatile int usr1_got;
+
+static void
+handler_usr1 (int signo)
+{
+  usr1_got++;
+}
+
+void
+forkoff (int nr)
+{
+  int child, save_parent = getpid ();
+  int i;
+  struct sigaction act, oldact;
+#ifdef THREAD
+  void *thread_result;
+#endif
+
+  memset (&act, 0, sizeof act);
+  act.sa_flags = SA_RESTART;
+  act.sa_handler = handler_usr1;
+  sigemptyset (&act.sa_mask);
+  i = sigaction (SIGUSR1, &act, &oldact);
+  assert (i == 0);
+
+  child = fork ();
+  switch (child)
+    {
+    case -1:
+      assert (0);
+    default:
+      printf ("parent%d: %d\n", nr, (int) child);
+
+      /* Sleep for a while to possibly get incorrectly ATTACH_THREADed by GDB
+         tracing the child fork with no longer valid thread/lwp entries of the
+         parent.  */
+
+      i = sleep (2);
+      assert (i == 0);
+
+      /* We must not get caught here (against a forgotten breakpoint).  */
+
+      var++;
+      marker ();
+
+#ifdef THREAD
+      /* And neither got caught our thread.  */
+
+      step = 99;
+      i = pthread_join (thread, &thread_result);
+      assert (i == 0);
+      assert (thread_result == (void *) 99UL);
+#endif
+
+      /* Be sure our child knows we did not get caught above.  */
+
+      i = kill (child, SIGUSR1);
+      assert (i == 0);
+
+      /* Sleep for a while to check GDB's `info threads' no longer tracks us in
+         the child fork.  */
+
+      i = sleep (2);
+      assert (i == 0);
+
+      _exit (0);
+    case 0:
+      printf ("child%d: %d\n", nr, (int) getpid ());
+
+      /* Let the parent signal us about its success.  Be careful of races.  */
+
+      for (;;)
+        {
+          /* Parent either died (and USR1_GOT is zero) or it succeeded.  */
+          if (getppid () != save_parent)
+            break;
+          if (kill (getppid (), 0) != 0)
+            break;
+          /* Parent succeeded?  */
+          if (usr1_got)
+            break;
+
+#ifdef THREAD
+          i = pthread_yield ();
+          assert (i == 0);
+#endif
+        }
+      assert (usr1_got);
+
+      /* We must get caught here (against a false watchpoint removal).  */
+
+      marker ();
+    }
+
+  i = sigaction (SIGUSR1, &oldact, NULL);
+  assert (i == 0);
+}