+void *
+evthread_setup_global_lock_(void *lock_, unsigned locktype, int enable_locks)
+{
+ /* there are four cases here:
+ 1) we're turning on debugging; locking is not on.
+ 2) we're turning on debugging; locking is on.
+ 3) we're turning on locking; debugging is not on.
+ 4) we're turning on locking; debugging is on. */
+
+ if (!enable_locks && _original_lock_fns.alloc == NULL) {
+ /* Case 1: allocate a debug lock. */
+ EVUTIL_ASSERT(lock_ == NULL);
+ return debug_lock_alloc(locktype);
+ } else if (!enable_locks && _original_lock_fns.alloc != NULL) {
+ /* Case 2: wrap the lock in a debug lock. */
+ struct debug_lock *lock;
+ EVUTIL_ASSERT(lock_ != NULL);
+
+ if (!(locktype & EVTHREAD_LOCKTYPE_RECURSIVE)) {
+ /* We can't wrap it: We need a recursive lock */
+ _original_lock_fns.free(lock_, locktype);
+ return debug_lock_alloc(locktype);
+ }
+ lock = mm_malloc(sizeof(struct debug_lock));
+ if (!lock) {
+ _original_lock_fns.free(lock_, locktype);
+ return NULL;
+ }
+ lock->lock = lock_;
+ lock->locktype = locktype;
+ lock->count = 0;
+ lock->held_by = 0;
+ return lock;
+ } else if (enable_locks && ! _evthread_lock_debugging_enabled) {
+ /* Case 3: allocate a regular lock */
+ EVUTIL_ASSERT(lock_ == NULL);
+ return _evthread_lock_fns.alloc(locktype);
+ } else {
+ /* Case 4: Fill in a debug lock with a real lock */
+ struct debug_lock *lock = lock_;
+ EVUTIL_ASSERT(enable_locks &&
+ _evthread_lock_debugging_enabled);
+ EVUTIL_ASSERT(lock->locktype == locktype);
+ EVUTIL_ASSERT(lock->lock == NULL);
+ lock->lock = _original_lock_fns.alloc(
+ locktype|EVTHREAD_LOCKTYPE_RECURSIVE);
+ if (!lock->lock) {
+ lock->count = -200;
+ mm_free(lock);
+ return NULL;
+ }
+ return lock;
+ }
+}
+
+