Merge lock annotation macros in threads.h

threads.h

@@ -33,6 +33,60 @@
 
 #include <time.h>
 
+/*
+ * Lock annotations.
+ *
+ * Clang provides support for doing basic thread-safety tests at
+ * compile-time, by marking which locks will/should be held when
+ * entering/leaving a functions.
+ *
+ * Furthermore, it is also possible to annotate variables and structure
+ * members to enforce that they are only accessed when certain locks are
+ * held.
+ */
+
+#if __has_extension(c_thread_safety_attributes)
+#define	__lock_annotate(x)	__attribute__((x))
+#else
+#define	__lock_annotate(x)
+#endif
+
+/* Structure implements a lock. */
+#define	__lockable		__lock_annotate(lockable)
+
+/* Function acquires an exclusive or shared lock. */
+#define	__locks_exclusive(...) \
+	__lock_annotate(exclusive_lock_function(__VA_ARGS__))
+#define	__locks_shared(...) \
+	__lock_annotate(shared_lock_function(__VA_ARGS__))
+
+/* Function attempts to acquire an exclusive or shared lock. */
+#define	__trylocks_exclusive(...) \
+	__lock_annotate(exclusive_trylock_function(__VA_ARGS__))
+#define	__trylocks_shared(...) \
+	__lock_annotate(shared_trylock_function(__VA_ARGS__))
+
+/* Function releases a lock. */
+#define	__unlocks(...)		__lock_annotate(unlock_function(__VA_ARGS__))
+
+/* Function asserts that an exclusive or shared lock is held. */
+#define	__asserts_exclusive(...) \
+	__lock_annotate(assert_exclusive_lock(__VA_ARGS__))
+#define	__asserts_shared(...) \
+	__lock_annotate(assert_shared_lock(__VA_ARGS__))
+
+
+/* Function requires that an exclusive or shared lock is or is not held. */
+#define	__requires_exclusive(...) \
+	__lock_annotate(exclusive_locks_required(__VA_ARGS__))
+#define	__requires_shared(...) \
+	__lock_annotate(shared_locks_required(__VA_ARGS__))
+#define	__requires_unlocked(...) \
+	__lock_annotate(locks_excluded(__VA_ARGS__))
+
+/* Function should not be analyzed. */
+#define	__no_lock_analysis	__lock_annotate(no_thread_safety_analysis)
+
 /*
  * The C11 threads interface.
  *