1 files changed, 90 insertions, 0 deletions
diff --git a/nptl/tst-mtx-trylock.c b/nptl/tst-mtx-trylock.c
new file mode 100644
index 0000000000..9df84a3019
--- /dev/null
+++ b/nptl/tst-mtx-trylock.c
@@ -0,0 +1,90 @@
+/* C11 threads trylock mutex tests.
+   Copyright (C) 2018 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 <threads.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <support/check.h>
+
+/* Shared mutex between child and parent.  */
+static mtx_t mutex;
+
+/* Shared counter to check possible race conditions.  */
+static char shrd_counter;
+
+/* Function to choose an action to do, depending on mtx_trylock
+   return value.  */
+static inline void
+choose_action (int action, char* thread_name)
+{
+  switch (action)
+    {
+      case thrd_success:
+        ++shrd_counter;
+
+	if (mtx_unlock (&mutex) != thrd_success)
+	  FAIL_EXIT1 ("mtx_unlock failed");
+      break;
+
+      case thrd_busy:
+        break;
+
+      case thrd_error:
+	FAIL_EXIT1 ("%s lock error", thread_name);
+        break;
+    }
+}
+
+static int
+child_add (void *arg)
+{
+  char child_name[] = "child";
+
+  /* Try to lock mutex.  */
+  choose_action (mtx_trylock (&mutex), child_name);
+
+  thrd_exit (thrd_success);
+}
+
+static int
+do_test (void)
+{
+  thrd_t id;
+  char parent_name[] = "parent";
+
+  if (mtx_init (&mutex, mtx_timed) != thrd_success)
+    FAIL_EXIT1 ("mtx_init failed");
+
+  if (thrd_create (&id, child_add, NULL) != thrd_success)
+    FAIL_EXIT1 ("thrd_create failed");
+
+  choose_action (mtx_trylock (&mutex), parent_name);
+
+  if (thrd_join (id, NULL) != thrd_success)
+    FAIL_EXIT1 ("thrd_join failed");
+
+  if (shrd_counter != 2 && shrd_counter != 1)
+    FAIL_EXIT1 ("shrd_counter != {1,2} (%d)", shrd_counter);
+
+  mtx_destroy (&mutex);
+
+  return 0;
+}
+
+#include <support/test-driver.c>