1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "callee_save_frame.h"
18#include "common_throws.h"
19#include "mirror/object-inl.h"
20
21namespace art {
22
23extern "C" int artLockObjectFromCode(mirror::Object* obj, Thread* self)
24    NO_THREAD_SAFETY_ANALYSIS
25    REQUIRES(!Roles::uninterruptible_)
26    REQUIRES_SHARED(Locks::mutator_lock_) /* EXCLUSIVE_LOCK_FUNCTION(Monitor::monitor_lock_) */ {
27  ScopedQuickEntrypointChecks sqec(self);
28  if (UNLIKELY(obj == nullptr)) {
29    ThrowNullPointerException("Null reference used for synchronization (monitor-enter)");
30    return -1;  // Failure.
31  } else {
32    obj = obj->MonitorEnter(self);  // May block
33    DCHECK(self->HoldsLock(obj));
34    // Exceptions can be thrown by monitor event listeners. This is expected to be rare however.
35    if (UNLIKELY(self->IsExceptionPending())) {
36      // TODO Remove this DCHECK if we expand the use of monitor callbacks.
37      DCHECK(Runtime::Current()->HasLoadedPlugins())
38          << "Exceptions are only expected to be thrown by plugin code which doesn't seem to be "
39          << "loaded.";
40      // We need to get rid of the lock
41      bool unlocked = obj->MonitorExit(self);
42      DCHECK(unlocked);
43      return -1;  // Failure.
44    } else {
45      DCHECK(self->HoldsLock(obj));
46      return 0;  // Success.
47    }
48  }
49}
50
51extern "C" int artUnlockObjectFromCode(mirror::Object* obj, Thread* self)
52    NO_THREAD_SAFETY_ANALYSIS
53    REQUIRES(!Roles::uninterruptible_)
54    REQUIRES_SHARED(Locks::mutator_lock_) /* UNLOCK_FUNCTION(Monitor::monitor_lock_) */ {
55  ScopedQuickEntrypointChecks sqec(self);
56  if (UNLIKELY(obj == nullptr)) {
57    ThrowNullPointerException("Null reference used for synchronization (monitor-exit)");
58    return -1;  // Failure.
59  } else {
60    // MonitorExit may throw exception.
61    return obj->MonitorExit(self) ? 0 /* Success */ : -1 /* Failure */;
62  }
63}
64
65}  // namespace art
66