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_BUFFERITEMCONSUMER_H 18 #define ANDROID_GUI_BUFFERITEMCONSUMER_H 19 20 #include <gui/ConsumerBase.h> 21 22 #include <ui/GraphicBuffer.h> 23 24 #include <utils/String8.h> 25 #include <utils/Vector.h> 26 #include <utils/threads.h> 27 28 #define ANDROID_GRAPHICS_BUFFERITEMCONSUMER_JNI_ID "mBufferItemConsumer" 29 30 namespace android { 31 32 class BufferQueue; 33 34 /** 35 * BufferItemConsumer is a BufferQueue consumer endpoint that allows clients 36 * access to the whole BufferItem entry from BufferQueue. Multiple buffers may 37 * be acquired at once, to be used concurrently by the client. This consumer can 38 * operate either in synchronous or asynchronous mode. 39 */ 40 class BufferItemConsumer: public ConsumerBase 41 { 42 public: 43 typedef ConsumerBase::FrameAvailableListener FrameAvailableListener; 44 45 enum { DEFAULT_MAX_BUFFERS = -1 }; 46 enum { INVALID_BUFFER_SLOT = BufferQueue::INVALID_BUFFER_SLOT }; 47 enum { NO_BUFFER_AVAILABLE = BufferQueue::NO_BUFFER_AVAILABLE }; 48 49 // Create a new buffer item consumer. The consumerUsage parameter determines 50 // the consumer usage flags passed to the graphics allocator. The 51 // bufferCount parameter specifies how many buffers can be locked for user 52 // access at the same time. 53 // controlledByApp tells whether this consumer is controlled by the 54 // application. 55 BufferItemConsumer(const sp<IGraphicBufferConsumer>& consumer, 56 uint32_t consumerUsage, int bufferCount = DEFAULT_MAX_BUFFERS, 57 bool controlledByApp = false); 58 59 virtual ~BufferItemConsumer(); 60 61 // set the name of the BufferItemConsumer that will be used to identify it in 62 // log messages. 63 void setName(const String8& name); 64 65 // Gets the next graphics buffer from the producer, filling out the 66 // passed-in BufferItem structure. Returns NO_BUFFER_AVAILABLE if the queue 67 // of buffers is empty, and INVALID_OPERATION if the maximum number of 68 // buffers is already acquired. 69 // 70 // Only a fixed number of buffers can be acquired at a time, determined by 71 // the construction-time bufferCount parameter. If INVALID_OPERATION is 72 // returned by acquireBuffer, then old buffers must be returned to the 73 // queue by calling releaseBuffer before more buffers can be acquired. 74 // 75 // If waitForFence is true, and the acquired BufferItem has a valid fence object, 76 // acquireBuffer will wait on the fence with no timeout before returning. 77 status_t acquireBuffer(BufferItem* item, nsecs_t presentWhen, 78 bool waitForFence = true); 79 80 // Returns an acquired buffer to the queue, allowing it to be reused. Since 81 // only a fixed number of buffers may be acquired at a time, old buffers 82 // must be released by calling releaseBuffer to ensure new buffers can be 83 // acquired by acquireBuffer. Once a BufferItem is released, the caller must 84 // not access any members of the BufferItem, and should immediately remove 85 // all of its references to the BufferItem itself. 86 status_t releaseBuffer(const BufferItem &item, 87 const sp<Fence>& releaseFence = Fence::NO_FENCE); 88 89 }; 90 91 } // namespace android 92 93 #endif // ANDROID_GUI_CPUCONSUMER_H 94