Allow a single-threaded program to cancel itself

There is nothing in the POSIX specification to disallow a
single-threaded program from cancelling itself, so we forcibly enable
multiple_threads to allow the next available cancellation point in the
thread to run.

Also added additional tests to cover various cancellation scenarios.

1 files changed, 65 insertions, 0 deletions

diff --git a/nptl/tst-cancel-self-cancelstate.c b/nptl/tst-cancel-self-cancelstate.c
new file mode 100644
index 0000000000..c82e6f3ced
--- /dev/null
+++ b/nptl/tst-cancel-self-cancelstate.c
@@ -0,0 +1,65 @@
+/* Copyright (C) 2012 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "tst-cancel-self-cleanup.c"
+
+
+static int
+do_test (void)
+{
+  int ret = 0;
+  volatile int should_fail = 1;
+
+  pthread_cleanup_push (cleanup, &should_fail);
+
+  if ((ret = pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, NULL)) != 0)
+    {
+      printf ("setcancelstate(disable) failed: %s\n", strerror (ret));
+      exit (1);
+    }
+
+  if ((ret = pthread_cancel (pthread_self ())) != 0)
+    {
+      printf ("cancel failed: %s\n", strerror (ret));
+      exit (1);
+    }
+
+  usleep (100);
+  should_fail = 0;
+
+  if ((ret = pthread_setcancelstate (PTHREAD_CANCEL_ENABLE, NULL)) != 0)
+    {
+      printf ("setcancelstate(enable) failed: %s\n", strerror (ret));
+      exit (1);
+    }
+
+  /* The write syscall within this printf should give us our cancellation
+     point.  */
+  printf ("Could not cancel self.\n");
+  pthread_cleanup_pop (0);
+
+  return 1;
+}
+
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"