Add MacOS X semaphore implementation

1 files changed, 31 insertions, 1 deletions

diff --git a/src/sem.h b/src/sem.h
index f0b7183..d557f22 100644
--- a/src/sem.h
+++ b/src/sem.h
@@ -34,8 +34,36 @@
 
 #include "log.h"
 
-#include <semaphore.h>
 
+#ifdef __APPLE__
+
+#include <dispatch/dispatch.h>
+
+/** Generic semaphore type */
+typedef dispatch_semaphore_t fastd_sem_t;
+
+
+/** Initializes a semaphore with a given value */
+static inline void fastd_sem_init(fastd_sem_t *sem, unsigned value) {
+	*sem = dispatch_semaphore_create(value);
+	if (!*sem)
+		exit_errno("dispatch_semaphore_create");
+}
+
+/** Increments the semaphore */
+static inline void fastd_sem_post(fastd_sem_t *sem) {
+	if (dispatch_semaphore_signal(*sem))
+		exit_errno("sem_post");
+}
+
+/** Tries to decrement the semaphore */
+static inline bool fastd_sem_trywait(fastd_sem_t *sem) {
+	return !dispatch_semaphore_wait(*sem, DISPATCH_TIME_NOW);
+}
+
+#else
+
+#include <semaphore.h>
 
 /** Generic semaphore type */
 typedef sem_t fastd_sem_t;
@@ -57,3 +85,5 @@ static inline void fastd_sem_post(fastd_sem_t *sem) {
 static inline bool fastd_sem_trywait(fastd_sem_t *sem) {
 	return !sem_trywait(sem);
 }
+
+#endif