BufferQueue.h revision 73ed82f809a40560fd3a6d53d18e5c846362d764
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_BUFFERQUEUE_H 18#define ANDROID_GUI_BUFFERQUEUE_H 19 20#include <gui/BufferQueueProducer.h> 21#include <gui/BufferQueueConsumer.h> 22#include <gui/IConsumerListener.h> 23 24// These are only required to keep other parts of the framework with incomplete 25// dependencies building successfully 26#include <gui/IGraphicBufferAlloc.h> 27 28#include <binder/IBinder.h> 29 30namespace android { 31 32// BQProducer and BQConsumer are thin shim classes to allow methods with the 33// same signature in both IGraphicBufferProducer and IGraphicBufferConsumer. 34// This will stop being an issue when we deprecate creating BufferQueues 35// directly (as opposed to using the *Producer and *Consumer interfaces). 36class BQProducer : public BnGraphicBufferProducer { 37public: 38 virtual status_t detachProducerBuffer(int slot) = 0; 39 virtual status_t attachProducerBuffer(int* slot, 40 const sp<GraphicBuffer>& buffer) = 0; 41 42 virtual status_t detachBuffer(int slot) { 43 return detachProducerBuffer(slot); 44 } 45 46 virtual status_t attachBuffer(int* slot, const sp<GraphicBuffer>& buffer) { 47 return attachProducerBuffer(slot, buffer); 48 } 49}; 50 51class BQConsumer : public BnGraphicBufferConsumer { 52public: 53 virtual status_t detachConsumerBuffer(int slot) = 0; 54 virtual status_t attachConsumerBuffer(int* slot, 55 const sp<GraphicBuffer>& buffer) = 0; 56 57 virtual status_t detachBuffer(int slot) { 58 return detachConsumerBuffer(slot); 59 } 60 61 virtual status_t attachBuffer(int* slot, const sp<GraphicBuffer>& buffer) { 62 return attachConsumerBuffer(slot, buffer); 63 } 64}; 65 66class BufferQueue : public BQProducer, 67 public BQConsumer, 68 private IBinder::DeathRecipient { 69public: 70 // BufferQueue will keep track of at most this value of buffers. 71 // Attempts at runtime to increase the number of buffers past this will fail. 72 enum { NUM_BUFFER_SLOTS = 32 }; 73 // Used as a placeholder slot# when the value isn't pointing to an existing buffer. 74 enum { INVALID_BUFFER_SLOT = IGraphicBufferConsumer::BufferItem::INVALID_BUFFER_SLOT }; 75 // Alias to <IGraphicBufferConsumer.h> -- please scope from there in future code! 76 enum { 77 NO_BUFFER_AVAILABLE = IGraphicBufferConsumer::NO_BUFFER_AVAILABLE, 78 PRESENT_LATER = IGraphicBufferConsumer::PRESENT_LATER, 79 }; 80 81 // When in async mode we reserve two slots in order to guarantee that the 82 // producer and consumer can run asynchronously. 83 enum { MAX_MAX_ACQUIRED_BUFFERS = NUM_BUFFER_SLOTS - 2 }; 84 85 // for backward source compatibility 86 typedef ::android::ConsumerListener ConsumerListener; 87 88 // ProxyConsumerListener is a ConsumerListener implementation that keeps a weak 89 // reference to the actual consumer object. It forwards all calls to that 90 // consumer object so long as it exists. 91 // 92 // This class exists to avoid having a circular reference between the 93 // BufferQueue object and the consumer object. The reason this can't be a weak 94 // reference in the BufferQueue class is because we're planning to expose the 95 // consumer side of a BufferQueue as a binder interface, which doesn't support 96 // weak references. 97 class ProxyConsumerListener : public BnConsumerListener { 98 public: 99 ProxyConsumerListener(const wp<ConsumerListener>& consumerListener); 100 virtual ~ProxyConsumerListener(); 101 virtual void onFrameAvailable(); 102 virtual void onBuffersReleased(); 103 virtual void onSidebandStreamChanged(); 104 private: 105 // mConsumerListener is a weak reference to the IConsumerListener. This is 106 // the raison d'etre of ProxyConsumerListener. 107 wp<ConsumerListener> mConsumerListener; 108 }; 109 110 // BufferQueue manages a pool of gralloc memory slots to be used by 111 // producers and consumers. allocator is used to allocate all the 112 // needed gralloc buffers. 113 BufferQueue(const sp<IGraphicBufferAlloc>& allocator = NULL); 114 115 static void createBufferQueue(sp<BnGraphicBufferProducer>* outProducer, 116 sp<BnGraphicBufferConsumer>* outConsumer, 117 const sp<IGraphicBufferAlloc>& allocator = NULL); 118 119 static void createBufferQueue(sp<IGraphicBufferProducer>* outProducer, 120 sp<IGraphicBufferConsumer>* outConsumer, 121 const sp<IGraphicBufferAlloc>& allocator = NULL); 122 123 virtual ~BufferQueue(); 124 125 /* 126 * IBinder::DeathRecipient interface 127 */ 128 129 virtual void binderDied(const wp<IBinder>& who); 130 131 /* 132 * IGraphicBufferProducer interface 133 */ 134 135 // Query native window attributes. The "what" values are enumerated in 136 // window.h (e.g. NATIVE_WINDOW_FORMAT). 137 virtual int query(int what, int* value); 138 139 // setBufferCount updates the number of available buffer slots. If this 140 // method succeeds, buffer slots will be both unallocated and owned by 141 // the BufferQueue object (i.e. they are not owned by the producer or 142 // consumer). 143 // 144 // This will fail if the producer has dequeued any buffers, or if 145 // bufferCount is invalid. bufferCount must generally be a value 146 // between the minimum undequeued buffer count (exclusive) and NUM_BUFFER_SLOTS 147 // (inclusive). It may also be set to zero (the default) to indicate 148 // that the producer does not wish to set a value. The minimum value 149 // can be obtained by calling query(NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS, 150 // ...). 151 // 152 // This may only be called by the producer. The consumer will be told 153 // to discard buffers through the onBuffersReleased callback. 154 virtual status_t setBufferCount(int bufferCount); 155 156 // requestBuffer returns the GraphicBuffer for slot N. 157 // 158 // In normal operation, this is called the first time slot N is returned 159 // by dequeueBuffer. It must be called again if dequeueBuffer returns 160 // flags indicating that previously-returned buffers are no longer valid. 161 virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf); 162 163 // dequeueBuffer gets the next buffer slot index for the producer to use. 164 // If a buffer slot is available then that slot index is written to the 165 // location pointed to by the buf argument and a status of OK is returned. 166 // If no slot is available then a status of -EBUSY is returned and buf is 167 // unmodified. 168 // 169 // The fence parameter will be updated to hold the fence associated with 170 // the buffer. The contents of the buffer must not be overwritten until the 171 // fence signals. If the fence is Fence::NO_FENCE, the buffer may be 172 // written immediately. 173 // 174 // The width and height parameters must be no greater than the minimum of 175 // GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv). 176 // An error due to invalid dimensions might not be reported until 177 // updateTexImage() is called. If width and height are both zero, the 178 // default values specified by setDefaultBufferSize() are used instead. 179 // 180 // The pixel formats are enumerated in graphics.h, e.g. 181 // HAL_PIXEL_FORMAT_RGBA_8888. If the format is 0, the default format 182 // will be used. 183 // 184 // The usage argument specifies gralloc buffer usage flags. The values 185 // are enumerated in gralloc.h, e.g. GRALLOC_USAGE_HW_RENDER. These 186 // will be merged with the usage flags specified by setConsumerUsageBits. 187 // 188 // The return value may be a negative error value or a non-negative 189 // collection of flags. If the flags are set, the return values are 190 // valid, but additional actions must be performed. 191 // 192 // If IGraphicBufferProducer::BUFFER_NEEDS_REALLOCATION is set, the 193 // producer must discard cached GraphicBuffer references for the slot 194 // returned in buf. 195 // If IGraphicBufferProducer::RELEASE_ALL_BUFFERS is set, the producer 196 // must discard cached GraphicBuffer references for all slots. 197 // 198 // In both cases, the producer will need to call requestBuffer to get a 199 // GraphicBuffer handle for the returned slot. 200 virtual status_t dequeueBuffer(int *buf, sp<Fence>* fence, bool async, 201 uint32_t width, uint32_t height, uint32_t format, uint32_t usage); 202 203 // See IGraphicBufferProducer::detachBuffer 204 virtual status_t detachProducerBuffer(int slot); 205 206 // See IGraphicBufferProducer::attachBuffer 207 virtual status_t attachProducerBuffer(int* slot, 208 const sp<GraphicBuffer>& buffer); 209 210 // queueBuffer returns a filled buffer to the BufferQueue. 211 // 212 // Additional data is provided in the QueueBufferInput struct. Notably, 213 // a timestamp must be provided for the buffer. The timestamp is in 214 // nanoseconds, and must be monotonically increasing. Its other semantics 215 // (zero point, etc) are producer-specific and should be documented by the 216 // producer. 217 // 218 // The caller may provide a fence that signals when all rendering 219 // operations have completed. Alternatively, NO_FENCE may be used, 220 // indicating that the buffer is ready immediately. 221 // 222 // Some values are returned in the output struct: the current settings 223 // for default width and height, the current transform hint, and the 224 // number of queued buffers. 225 virtual status_t queueBuffer(int buf, 226 const QueueBufferInput& input, QueueBufferOutput* output); 227 228 // cancelBuffer returns a dequeued buffer to the BufferQueue, but doesn't 229 // queue it for use by the consumer. 230 // 231 // The buffer will not be overwritten until the fence signals. The fence 232 // will usually be the one obtained from dequeueBuffer. 233 virtual void cancelBuffer(int buf, const sp<Fence>& fence); 234 235 // connect attempts to connect a producer API to the BufferQueue. This 236 // must be called before any other IGraphicBufferProducer methods are 237 // called except for getAllocator. A consumer must already be connected. 238 // 239 // This method will fail if connect was previously called on the 240 // BufferQueue and no corresponding disconnect call was made (i.e. if 241 // it's still connected to a producer). 242 // 243 // APIs are enumerated in window.h (e.g. NATIVE_WINDOW_API_CPU). 244 virtual status_t connect(const sp<IBinder>& token, 245 int api, bool producerControlledByApp, QueueBufferOutput* output); 246 247 // disconnect attempts to disconnect a producer API from the BufferQueue. 248 // Calling this method will cause any subsequent calls to other 249 // IGraphicBufferProducer methods to fail except for getAllocator and connect. 250 // Successfully calling connect after this will allow the other methods to 251 // succeed again. 252 // 253 // This method will fail if the the BufferQueue is not currently 254 // connected to the specified producer API. 255 virtual status_t disconnect(int api); 256 257 // Attaches a sideband buffer stream to the BufferQueue. 258 // 259 // A sideband stream is a device-specific mechanism for passing buffers 260 // from the producer to the consumer without using dequeueBuffer/ 261 // queueBuffer. If a sideband stream is present, the consumer can choose 262 // whether to acquire buffers from the sideband stream or from the queued 263 // buffers. 264 // 265 // Passing NULL or a different stream handle will detach the previous 266 // handle if any. 267 virtual status_t setSidebandStream(const sp<NativeHandle>& stream); 268 269 /* 270 * IGraphicBufferConsumer interface 271 */ 272 273 // acquireBuffer attempts to acquire ownership of the next pending buffer in 274 // the BufferQueue. If no buffer is pending then it returns NO_BUFFER_AVAILABLE. If a 275 // buffer is successfully acquired, the information about the buffer is 276 // returned in BufferItem. If the buffer returned had previously been 277 // acquired then the BufferItem::mGraphicBuffer field of buffer is set to 278 // NULL and it is assumed that the consumer still holds a reference to the 279 // buffer. 280 // 281 // If presentWhen is nonzero, it indicates the time when the buffer will 282 // be displayed on screen. If the buffer's timestamp is farther in the 283 // future, the buffer won't be acquired, and PRESENT_LATER will be 284 // returned. The presentation time is in nanoseconds, and the time base 285 // is CLOCK_MONOTONIC. 286 virtual status_t acquireBuffer(BufferItem* buffer, nsecs_t presentWhen); 287 288 // See IGraphicBufferConsumer::detachBuffer 289 virtual status_t detachConsumerBuffer(int slot); 290 291 // See IGraphicBufferConsumer::attachBuffer 292 virtual status_t attachConsumerBuffer(int* slot, 293 const sp<GraphicBuffer>& buffer); 294 295 // releaseBuffer releases a buffer slot from the consumer back to the 296 // BufferQueue. This may be done while the buffer's contents are still 297 // being accessed. The fence will signal when the buffer is no longer 298 // in use. frameNumber is used to indentify the exact buffer returned. 299 // 300 // If releaseBuffer returns STALE_BUFFER_SLOT, then the consumer must free 301 // any references to the just-released buffer that it might have, as if it 302 // had received a onBuffersReleased() call with a mask set for the released 303 // buffer. 304 // 305 // Note that the dependencies on EGL will be removed once we switch to using 306 // the Android HW Sync HAL. 307 virtual status_t releaseBuffer(int buf, uint64_t frameNumber, 308 EGLDisplay display, EGLSyncKHR fence, 309 const sp<Fence>& releaseFence); 310 311 // consumerConnect connects a consumer to the BufferQueue. Only one 312 // consumer may be connected, and when that consumer disconnects the 313 // BufferQueue is placed into the "abandoned" state, causing most 314 // interactions with the BufferQueue by the producer to fail. 315 // controlledByApp indicates whether the consumer is controlled by 316 // the application. 317 // 318 // consumer may not be NULL. 319 virtual status_t consumerConnect(const sp<IConsumerListener>& consumer, bool controlledByApp); 320 321 // consumerDisconnect disconnects a consumer from the BufferQueue. All 322 // buffers will be freed and the BufferQueue is placed in the "abandoned" 323 // state, causing most interactions with the BufferQueue by the producer to 324 // fail. 325 virtual status_t consumerDisconnect(); 326 327 // getReleasedBuffers sets the value pointed to by slotMask to a bit mask 328 // indicating which buffer slots have been released by the BufferQueue 329 // but have not yet been released by the consumer. 330 // 331 // This should be called from the onBuffersReleased() callback. 332 virtual status_t getReleasedBuffers(uint32_t* slotMask); 333 334 // setDefaultBufferSize is used to set the size of buffers returned by 335 // dequeueBuffer when a width and height of zero is requested. Default 336 // is 1x1. 337 virtual status_t setDefaultBufferSize(uint32_t w, uint32_t h); 338 339 // setDefaultMaxBufferCount sets the default value for the maximum buffer 340 // count (the initial default is 2). If the producer has requested a 341 // buffer count using setBufferCount, the default buffer count will only 342 // take effect if the producer sets the count back to zero. 343 // 344 // The count must be between 2 and NUM_BUFFER_SLOTS, inclusive. 345 virtual status_t setDefaultMaxBufferCount(int bufferCount); 346 347 // disableAsyncBuffer disables the extra buffer used in async mode 348 // (when both producer and consumer have set their "isControlledByApp" 349 // flag) and has dequeueBuffer() return WOULD_BLOCK instead. 350 // 351 // This can only be called before consumerConnect(). 352 virtual status_t disableAsyncBuffer(); 353 354 // setMaxAcquiredBufferCount sets the maximum number of buffers that can 355 // be acquired by the consumer at one time (default 1). This call will 356 // fail if a producer is connected to the BufferQueue. 357 virtual status_t setMaxAcquiredBufferCount(int maxAcquiredBuffers); 358 359 // setConsumerName sets the name used in logging 360 virtual void setConsumerName(const String8& name); 361 362 // setDefaultBufferFormat allows the BufferQueue to create 363 // GraphicBuffers of a defaultFormat if no format is specified 364 // in dequeueBuffer. Formats are enumerated in graphics.h; the 365 // initial default is HAL_PIXEL_FORMAT_RGBA_8888. 366 virtual status_t setDefaultBufferFormat(uint32_t defaultFormat); 367 368 // setConsumerUsageBits will turn on additional usage bits for dequeueBuffer. 369 // These are merged with the bits passed to dequeueBuffer. The values are 370 // enumerated in gralloc.h, e.g. GRALLOC_USAGE_HW_RENDER; the default is 0. 371 virtual status_t setConsumerUsageBits(uint32_t usage); 372 373 // setTransformHint bakes in rotation to buffers so overlays can be used. 374 // The values are enumerated in window.h, e.g. 375 // NATIVE_WINDOW_TRANSFORM_ROT_90. The default is 0 (no transform). 376 virtual status_t setTransformHint(uint32_t hint); 377 378 // Retrieve the BufferQueue's sideband stream, if any. 379 virtual sp<NativeHandle> getSidebandStream() const; 380 381 // dump our state in a String 382 virtual void dump(String8& result, const char* prefix) const; 383 384private: 385 sp<BufferQueueProducer> mProducer; 386 sp<BufferQueueConsumer> mConsumer; 387}; 388 389// ---------------------------------------------------------------------------- 390}; // namespace android 391 392#endif // ANDROID_GUI_BUFFERQUEUE_H 393