1 files changed, 62 insertions, 0 deletions
diff --git a/tests/mutex4.c b/tests/mutex4.c
new file mode 100644
index 0000000..5290f2a
--- /dev/null
+++ b/tests/mutex4.c
@@ -0,0 +1,62 @@
+/* 
+ * mutex4.c
+ *
+ * Thread A locks mutex - thread B tries to unlock.
+ *
+ * Depends on API functions: 
+ *	pthread_mutex_lock()
+ *	pthread_mutex_trylock()
+ *	pthread_mutex_unlock()
+ */
+
+#include "test.h"
+ 
+pthread_mutex_t mutex1 = PTHREAD_MUTEX_INITIALIZER;
+pthread_mutex_t locker_done = PTHREAD_MUTEX_INITIALIZER;
+pthread_mutex_t unlocker_done = PTHREAD_MUTEX_INITIALIZER;
+
+static int washere = 0;
+
+void * locker(void * arg)
+{
+  assert(pthread_mutex_lock(&locker_start) == 0);
+  assert(pthread_mutex_lock(&mutex1) == 0);
+  assert(pthread_mutex_unlock(&locker_start) == 0);
+
+  /* Wait for unlocker to finish */
+  assert(pthread_mutex_lock(&unlocker_end) == 0);
+  assert(pthread_mutex_unlock(&mutex1) == 0);
+
+  return 0;
+}
+ 
+void * unlocker(void * arg)
+{
+  /* Wait for locker to lock mutex1 */
+  assert(pthread_mutex_lock(&unlocker_start) == 0);
+
+  assert(pthread_mutex_unlock(&mutex1) == EPERM);
+
+  assert(pthread_mutex_unlock(&unlocker_start) == 0);
+
+  return 0;
+}
+ 
+int
+main()
+{
+  pthread_t t;
+
+  assert(pthread_mutex_lock(&locker_start) == 0);
+  assert(pthread_mutex_lock(&unlocker_start) == 0);
+
+  assert(pthread_create(&t, NULL, locker, NULL) == 0);
+  assert(pthread_mutex_unlock(&locker_start) == 0);
+  Sleep(0);
+
+  assert(pthread_create(&t, NULL, unlocker, NULL) == 0);
+  assert(pthread_mutex_unlock(&unlocker_start) == 0);
+  Sleep(0);
+
+  return 0;
+}