add C11 mutex functions
authorJens Gustedt <Jens.Gustedt@inria.fr>
Sun, 7 Sep 2014 02:07:22 +0000 (22:07 -0400)
committerRich Felker <dalias@aerifal.cx>
Sun, 7 Sep 2014 02:07:22 +0000 (22:07 -0400)
src/thread/mtx_destroy.c [new file with mode: 0644]
src/thread/mtx_init.c [new file with mode: 0644]
src/thread/mtx_lock.c [new file with mode: 0644]
src/thread/mtx_timedlock.c [new file with mode: 0644]
src/thread/mtx_trylock.c [new file with mode: 0644]
src/thread/mtx_unlock.c [new file with mode: 0644]

diff --git a/src/thread/mtx_destroy.c b/src/thread/mtx_destroy.c
new file mode 100644 (file)
index 0000000..40a0899
--- /dev/null
@@ -0,0 +1,5 @@
+#include <threads.h>
+
+void mtx_destroy(mtx_t *mtx)
+{
+}
diff --git a/src/thread/mtx_init.c b/src/thread/mtx_init.c
new file mode 100644 (file)
index 0000000..4826f76
--- /dev/null
@@ -0,0 +1,10 @@
+#include "pthread_impl.h"
+#include <threads.h>
+
+int mtx_init(mtx_t *m, int type)
+{
+       *m = (mtx_t){
+               ._m_type = ((type&mtx_recursive) ? PTHREAD_MUTEX_RECURSIVE : PTHREAD_MUTEX_NORMAL),
+       };
+       return thrd_success;
+}
diff --git a/src/thread/mtx_lock.c b/src/thread/mtx_lock.c
new file mode 100644 (file)
index 0000000..5c2415c
--- /dev/null
@@ -0,0 +1,12 @@
+#include "pthread_impl.h"
+#include <threads.h>
+
+int mtx_lock(mtx_t *m)
+{
+       if (m->_m_type == PTHREAD_MUTEX_NORMAL && !a_cas(&m->_m_lock, 0, EBUSY))
+               return thrd_success;
+       /* Calling mtx_timedlock with a null pointer is an extension.
+        * It is convenient, here to avoid duplication of the logic
+        * for return values. */
+       return mtx_timedlock(m, 0);
+}
diff --git a/src/thread/mtx_timedlock.c b/src/thread/mtx_timedlock.c
new file mode 100644 (file)
index 0000000..bcc152c
--- /dev/null
@@ -0,0 +1,14 @@
+#include <threads.h>
+#include <errno.h>
+
+int __pthread_mutex_timedlock(mtx_t *restrict, const struct timespec *restrict);
+
+int mtx_timedlock(mtx_t *restrict m, const struct timespec *restrict ts)
+{
+       int ret = __pthread_mutex_timedlock(m, ts);
+       switch (ret) {
+       default:        return thrd_error;
+       case 0:         return thrd_success;
+       case ETIMEDOUT: return thrd_timedout;
+       }
+}
diff --git a/src/thread/mtx_trylock.c b/src/thread/mtx_trylock.c
new file mode 100644 (file)
index 0000000..61e7694
--- /dev/null
@@ -0,0 +1,17 @@
+#include "pthread_impl.h"
+#include <threads.h>
+
+int __pthread_mutex_trylock(mtx_t *);
+
+int mtx_trylock(mtx_t *m)
+{
+       if (m->_m_type == PTHREAD_MUTEX_NORMAL)
+               return (a_cas(&m->_m_lock, 0, EBUSY) & EBUSY) ? thrd_busy : thrd_success;
+
+       int ret = __pthread_mutex_trylock(m);
+       switch (ret) {
+       default:    return thrd_error;
+       case 0:     return thrd_success;
+       case EBUSY: return thrd_busy;
+       }
+}
diff --git a/src/thread/mtx_unlock.c b/src/thread/mtx_unlock.c
new file mode 100644 (file)
index 0000000..5033ace
--- /dev/null
@@ -0,0 +1,11 @@
+#include <threads.h>
+
+int __pthread_mutex_unlock(mtx_t *);
+
+int mtx_unlock(mtx_t *mtx)
+{
+       /* The only cases where pthread_mutex_unlock can return an
+        * error are undefined behavior for C11 mtx_unlock, so we can
+        * assume it does not return an error and simply tail call. */
+       return __pthread_mutex_unlock(mtx);
+}