1 files changed, 15 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/thread/pthread_rwlock_tryrdlock.c b/libc-top-half/musl/src/thread/pthread_rwlock_tryrdlock.c
new file mode 100644
index 0000000..c13bc9c
--- /dev/null
+++ b/libc-top-half/musl/src/thread/pthread_rwlock_tryrdlock.c
@@ -0,0 +1,15 @@
+#include "pthread_impl.h"
+
+int __pthread_rwlock_tryrdlock(pthread_rwlock_t *rw)
+{
+	int val, cnt;
+	do {
+		val = rw->_rw_lock;
+		cnt = val & 0x7fffffff;
+		if (cnt == 0x7fffffff) return EBUSY;
+		if (cnt == 0x7ffffffe) return EAGAIN;
+	} while (a_cas(&rw->_rw_lock, val, val+1) != val);
+	return 0;
+}
+
+weak_alias(__pthread_rwlock_tryrdlock, pthread_rwlock_tryrdlock);