2 * Copyright (C) 2012 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #ifndef ANDROID_FENCE_H
18 #define ANDROID_FENCE_H
21 #include <sys/types.h>
23 #include <ui/ANativeObjectBase.h>
24 #include <ui/PixelFormat.h>
26 #include <utils/Flattenable.h>
27 #include <utils/String8.h>
29 struct ANativeWindowBuffer;
33 // ===========================================================================
35 // ===========================================================================
38 : public LightRefBase<Fence>, public Flattenable
41 static const sp<Fence> NO_FENCE;
43 // Construct a new Fence object with an invalid file descriptor. This
44 // should be done when the Fence object will be set up by unflattening
48 // Construct a new Fence object to manage a given fence file descriptor.
49 // When the new Fence object is destructed the file descriptor will be
53 // Check whether the Fence has an open fence file descriptor. Most Fence
54 // methods treat an invalid file descriptor just like a valid fence that
55 // is already signalled, so using this is usually not necessary.
56 bool isValid() const { return mFenceFd != -1; }
58 // wait waits for up to timeout milliseconds for the fence to signal. If
59 // the fence signals then NO_ERROR is returned. If the timeout expires
60 // before the fence signals then -ETIME is returned. A timeout of
61 // TIMEOUT_NEVER may be used to indicate that the call should wait
62 // indefinitely for the fence to signal.
63 int wait(unsigned int timeout);
65 // TIMEOUT_NEVER may be passed to the wait method to indicate that it
66 // should wait indefinitely for the fence to signal.
67 enum { TIMEOUT_NEVER = -1 };
69 // merge combines two Fence objects, creating a new Fence object that
70 // becomes signaled when both f1 and f2 are signaled (even if f1 or f2 is
71 // destroyed before it becomes signaled). The name argument specifies the
72 // human-readable name to associated with the new Fence object.
73 static sp<Fence> merge(const String8& name, const sp<Fence>& f1,
76 // Return a duplicate of the fence file descriptor. The caller is
77 // responsible for closing the returned file descriptor. On error, -1 will
78 // be returned and errno will indicate the problem.
81 // Flattenable interface
82 size_t getFlattenedSize() const;
83 size_t getFdCount() const;
84 status_t flatten(void* buffer, size_t size,
85 int fds[], size_t count) const;
86 status_t unflatten(void const* buffer, size_t size,
87 int fds[], size_t count);
90 // Only allow instantiation using ref counting.
91 friend class LightRefBase<Fence>;
95 Fence(const Fence& rhs);
96 Fence& operator = (const Fence& rhs);
97 const Fence& operator = (const Fence& rhs) const;
102 }; // namespace android
104 #endif // ANDROID_FENCE_H