Fence.h revision f9783af225aa3b41ec0af36f90941a714269abb7
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#ifndef ANDROID_FENCE_H 18#define ANDROID_FENCE_H 19 20#include <stdint.h> 21#include <limits.h> 22#include <sys/types.h> 23 24#include <ui/ANativeObjectBase.h> 25#include <ui/PixelFormat.h> 26#include <ui/Rect.h> 27#include <utils/Flattenable.h> 28#include <utils/String8.h> 29 30struct ANativeWindowBuffer; 31 32namespace android { 33 34// =========================================================================== 35// Fence 36// =========================================================================== 37 38class Fence 39 : public LightRefBase<Fence>, public Flattenable 40{ 41public: 42 static const sp<Fence> NO_FENCE; 43 44 // Construct a new Fence object with an invalid file descriptor. This 45 // should be done when the Fence object will be set up by unflattening 46 // serialized data. 47 Fence(); 48 49 // Construct a new Fence object to manage a given fence file descriptor. 50 // When the new Fence object is destructed the file descriptor will be 51 // closed. 52 Fence(int fenceFd); 53 54 // wait waits for up to timeout milliseconds for the fence to signal. If 55 // the fence signals then NO_ERROR is returned. If the timeout expires 56 // before the fence signals then -ETIME is returned. A timeout of 57 // TIMEOUT_NEVER may be used to indicate that the call should wait 58 // indefinitely for the fence to signal. 59 int wait(unsigned int timeout); 60 61 // TIMEOUT_NEVER may be passed to the wait method to indicate that it 62 // should wait indefinitely for the fence to signal. 63 enum { TIMEOUT_NEVER = UINT_MAX }; 64 65 // merge combines two Fence objects, creating a new Fence object that 66 // becomes signaled when both f1 and f2 are signaled (even if f1 or f2 is 67 // destroyed before it becomes signaled). The name argument specifies the 68 // human-readable name to associated with the new Fence object. 69 static sp<Fence> merge(const String8& name, const sp<Fence>& f1, 70 const sp<Fence>& f2); 71 72 // Return a duplicate of the fence file descriptor. The caller is 73 // responsible for closing the returned file descriptor. On error, -1 will 74 // be returned and errno will indicate the problem. 75 int dup() const; 76 77 // Flattenable interface 78 size_t getFlattenedSize() const; 79 size_t getFdCount() const; 80 status_t flatten(void* buffer, size_t size, 81 int fds[], size_t count) const; 82 status_t unflatten(void const* buffer, size_t size, 83 int fds[], size_t count); 84 85private: 86 // Only allow instantiation using ref counting. 87 friend class LightRefBase<Fence>; 88 virtual ~Fence(); 89 90 // Disallow copying 91 Fence(const Fence& rhs); 92 Fence& operator = (const Fence& rhs); 93 const Fence& operator = (const Fence& rhs) const; 94 95 int mFenceFd; 96}; 97 98}; // namespace android 99 100#endif // ANDROID_FENCE_H 101