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_GUI_CPUCONSUMER_H 18 #define ANDROID_GUI_CPUCONSUMER_H 19 20 #include <system/window.h> 21 22 #include <gui/ConsumerBase.h> 23 #include <gui/BufferQueue.h> 24 25 #include <utils/Vector.h> 26 27 28 namespace android { 29 30 class BufferQueue; 31 class GraphicBuffer; 32 class String8; 33 34 /** 35 * CpuConsumer is a BufferQueue consumer endpoint that allows direct CPU 36 * access to the underlying gralloc buffers provided by BufferQueue. Multiple 37 * buffers may be acquired by it at once, to be used concurrently by the 38 * CpuConsumer owner. Sets gralloc usage flags to be software-read-only. 39 * This queue is synchronous by default. 40 */ 41 42 class CpuConsumer : public ConsumerBase 43 { 44 public: 45 typedef ConsumerBase::FrameAvailableListener FrameAvailableListener; 46 47 struct LockedBuffer { 48 uint8_t *data; 49 uint32_t width; 50 uint32_t height; 51 PixelFormat format; 52 uint32_t stride; 53 Rect crop; 54 uint32_t transform; 55 uint32_t scalingMode; 56 int64_t timestamp; 57 android_dataspace dataSpace; 58 uint64_t frameNumber; 59 // this is the same as format, except for formats that are compatible with 60 // a flexible format (e.g. HAL_PIXEL_FORMAT_YCbCr_420_888). In the latter 61 // case this contains that flexible format 62 PixelFormat flexFormat; 63 // Values below are only valid when using HAL_PIXEL_FORMAT_YCbCr_420_888 64 // or compatible format, in which case LockedBuffer::data 65 // contains the Y channel, and stride is the Y channel stride. For other 66 // formats, these will all be 0. 67 uint8_t *dataCb; 68 uint8_t *dataCr; 69 uint32_t chromaStride; 70 uint32_t chromaStep; 71 LockedBufferLockedBuffer72 LockedBuffer() : 73 data(nullptr), 74 width(0), 75 height(0), 76 format(PIXEL_FORMAT_NONE), 77 stride(0), 78 crop(Rect::EMPTY_RECT), 79 transform(0), 80 scalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE), 81 timestamp(0), 82 dataSpace(HAL_DATASPACE_UNKNOWN), 83 frameNumber(0), 84 flexFormat(PIXEL_FORMAT_NONE), 85 dataCb(nullptr), 86 dataCr(nullptr), 87 chromaStride(0), 88 chromaStep(0) 89 {} 90 }; 91 92 // Create a new CPU consumer. The maxLockedBuffers parameter specifies 93 // how many buffers can be locked for user access at the same time. 94 CpuConsumer(const sp<IGraphicBufferConsumer>& bq, 95 size_t maxLockedBuffers, bool controlledByApp = false); 96 97 // Gets the next graphics buffer from the producer and locks it for CPU use, 98 // filling out the passed-in locked buffer structure with the native pointer 99 // and metadata. Returns BAD_VALUE if no new buffer is available, and 100 // NOT_ENOUGH_DATA if the maximum number of buffers is already locked. 101 // 102 // Only a fixed number of buffers can be locked at a time, determined by the 103 // construction-time maxLockedBuffers parameter. If INVALID_OPERATION is 104 // returned by lockNextBuffer, then old buffers must be returned to the queue 105 // by calling unlockBuffer before more buffers can be acquired. 106 status_t lockNextBuffer(LockedBuffer *nativeBuffer); 107 108 // Returns a locked buffer to the queue, allowing it to be reused. Since 109 // only a fixed number of buffers may be locked at a time, old buffers must 110 // be released by calling unlockBuffer to ensure new buffers can be acquired by 111 // lockNextBuffer. 112 status_t unlockBuffer(const LockedBuffer &nativeBuffer); 113 114 private: 115 // Maximum number of buffers that can be locked at a time 116 const size_t mMaxLockedBuffers; 117 118 // Tracking for buffers acquired by the user 119 struct AcquiredBuffer { 120 static constexpr uintptr_t kUnusedId = 0; 121 122 // Need to track the original mSlot index and the buffer itself because 123 // the mSlot entry may be freed/reused before the acquired buffer is 124 // released. 125 int mSlot; 126 sp<GraphicBuffer> mGraphicBuffer; 127 uintptr_t mLockedBufferId; 128 AcquiredBufferAcquiredBuffer129 AcquiredBuffer() : 130 mSlot(BufferQueue::INVALID_BUFFER_SLOT), 131 mLockedBufferId(kUnusedId) { 132 } 133 resetAcquiredBuffer134 void reset() { 135 mSlot = BufferQueue::INVALID_BUFFER_SLOT; 136 mGraphicBuffer.clear(); 137 mLockedBufferId = kUnusedId; 138 } 139 }; 140 141 size_t findAcquiredBufferLocked(uintptr_t id) const; 142 143 status_t lockBufferItem(const BufferItem& item, LockedBuffer* outBuffer) const; 144 145 Vector<AcquiredBuffer> mAcquiredBuffers; 146 147 // Count of currently locked buffers 148 size_t mCurrentLockedBuffers; 149 }; 150 151 } // namespace android 152 153 #endif // ANDROID_GUI_CPUCONSUMER_H 154