BufferQueue.h revision fd34b65f717b84fa06d8c37f41b070f41d0ad3a3
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<IGraphicBufferProducer>* outProducer, 116 sp<IGraphicBufferConsumer>* outConsumer, 117 const sp<IGraphicBufferAlloc>& allocator = NULL); 118 119 virtual ~BufferQueue(); 120 121 /* 122 * IBinder::DeathRecipient interface 123 */ 124 125 virtual void binderDied(const wp<IBinder>& who); 126 127 /* 128 * IGraphicBufferProducer interface 129 */ 130 131 // Query native window attributes. The "what" values are enumerated in 132 // window.h (e.g. NATIVE_WINDOW_FORMAT). 133 virtual int query(int what, int* value); 134 135 // setBufferCount updates the number of available buffer slots. If this 136 // method succeeds, buffer slots will be both unallocated and owned by 137 // the BufferQueue object (i.e. they are not owned by the producer or 138 // consumer). 139 // 140 // This will fail if the producer has dequeued any buffers, or if 141 // bufferCount is invalid. bufferCount must generally be a value 142 // between the minimum undequeued buffer count (exclusive) and NUM_BUFFER_SLOTS 143 // (inclusive). It may also be set to zero (the default) to indicate 144 // that the producer does not wish to set a value. The minimum value 145 // can be obtained by calling query(NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS, 146 // ...). 147 // 148 // This may only be called by the producer. The consumer will be told 149 // to discard buffers through the onBuffersReleased callback. 150 virtual status_t setBufferCount(int bufferCount); 151 152 // requestBuffer returns the GraphicBuffer for slot N. 153 // 154 // In normal operation, this is called the first time slot N is returned 155 // by dequeueBuffer. It must be called again if dequeueBuffer returns 156 // flags indicating that previously-returned buffers are no longer valid. 157 virtual status_t requestBuffer(int slot, sp<GraphicBuffer>* buf); 158 159 // dequeueBuffer gets the next buffer slot index for the producer to use. 160 // If a buffer slot is available then that slot index is written to the 161 // location pointed to by the buf argument and a status of OK is returned. 162 // If no slot is available then a status of -EBUSY is returned and buf is 163 // unmodified. 164 // 165 // The fence parameter will be updated to hold the fence associated with 166 // the buffer. The contents of the buffer must not be overwritten until the 167 // fence signals. If the fence is Fence::NO_FENCE, the buffer may be 168 // written immediately. 169 // 170 // The width and height parameters must be no greater than the minimum of 171 // GL_MAX_VIEWPORT_DIMS and GL_MAX_TEXTURE_SIZE (see: glGetIntegerv). 172 // An error due to invalid dimensions might not be reported until 173 // updateTexImage() is called. If width and height are both zero, the 174 // default values specified by setDefaultBufferSize() are used instead. 175 // 176 // The pixel formats are enumerated in graphics.h, e.g. 177 // HAL_PIXEL_FORMAT_RGBA_8888. If the format is 0, the default format 178 // will be used. 179 // 180 // The usage argument specifies gralloc buffer usage flags. The values 181 // are enumerated in gralloc.h, e.g. GRALLOC_USAGE_HW_RENDER. These 182 // will be merged with the usage flags specified by setConsumerUsageBits. 183 // 184 // The return value may be a negative error value or a non-negative 185 // collection of flags. If the flags are set, the return values are 186 // valid, but additional actions must be performed. 187 // 188 // If IGraphicBufferProducer::BUFFER_NEEDS_REALLOCATION is set, the 189 // producer must discard cached GraphicBuffer references for the slot 190 // returned in buf. 191 // If IGraphicBufferProducer::RELEASE_ALL_BUFFERS is set, the producer 192 // must discard cached GraphicBuffer references for all slots. 193 // 194 // In both cases, the producer will need to call requestBuffer to get a 195 // GraphicBuffer handle for the returned slot. 196 virtual status_t dequeueBuffer(int *buf, sp<Fence>* fence, bool async, 197 uint32_t width, uint32_t height, uint32_t format, uint32_t usage); 198 199 // See IGraphicBufferProducer::detachBuffer 200 virtual status_t detachProducerBuffer(int slot); 201 202 // See IGraphicBufferProducer::attachBuffer 203 virtual status_t attachProducerBuffer(int* slot, 204 const sp<GraphicBuffer>& buffer); 205 206 // queueBuffer returns a filled buffer to the BufferQueue. 207 // 208 // Additional data is provided in the QueueBufferInput struct. Notably, 209 // a timestamp must be provided for the buffer. The timestamp is in 210 // nanoseconds, and must be monotonically increasing. Its other semantics 211 // (zero point, etc) are producer-specific and should be documented by the 212 // producer. 213 // 214 // The caller may provide a fence that signals when all rendering 215 // operations have completed. Alternatively, NO_FENCE may be used, 216 // indicating that the buffer is ready immediately. 217 // 218 // Some values are returned in the output struct: the current settings 219 // for default width and height, the current transform hint, and the 220 // number of queued buffers. 221 virtual status_t queueBuffer(int buf, 222 const QueueBufferInput& input, QueueBufferOutput* output); 223 224 // cancelBuffer returns a dequeued buffer to the BufferQueue, but doesn't 225 // queue it for use by the consumer. 226 // 227 // The buffer will not be overwritten until the fence signals. The fence 228 // will usually be the one obtained from dequeueBuffer. 229 virtual void cancelBuffer(int buf, const sp<Fence>& fence); 230 231 // See IGraphicBufferProducer::connect 232 virtual status_t connect(const sp<IProducerListener>& listener, 233 int api, bool producerControlledByApp, QueueBufferOutput* output); 234 235 // disconnect attempts to disconnect a producer API from the BufferQueue. 236 // Calling this method will cause any subsequent calls to other 237 // IGraphicBufferProducer methods to fail except for getAllocator and connect. 238 // Successfully calling connect after this will allow the other methods to 239 // succeed again. 240 // 241 // This method will fail if the the BufferQueue is not currently 242 // connected to the specified producer API. 243 virtual status_t disconnect(int api); 244 245 // Attaches a sideband buffer stream to the BufferQueue. 246 // 247 // A sideband stream is a device-specific mechanism for passing buffers 248 // from the producer to the consumer without using dequeueBuffer/ 249 // queueBuffer. If a sideband stream is present, the consumer can choose 250 // whether to acquire buffers from the sideband stream or from the queued 251 // buffers. 252 // 253 // Passing NULL or a different stream handle will detach the previous 254 // handle if any. 255 virtual status_t setSidebandStream(const sp<NativeHandle>& stream); 256 257 /* 258 * IGraphicBufferConsumer interface 259 */ 260 261 // acquireBuffer attempts to acquire ownership of the next pending buffer in 262 // the BufferQueue. If no buffer is pending then it returns NO_BUFFER_AVAILABLE. If a 263 // buffer is successfully acquired, the information about the buffer is 264 // returned in BufferItem. If the buffer returned had previously been 265 // acquired then the BufferItem::mGraphicBuffer field of buffer is set to 266 // NULL and it is assumed that the consumer still holds a reference to the 267 // buffer. 268 // 269 // If presentWhen is nonzero, it indicates the time when the buffer will 270 // be displayed on screen. If the buffer's timestamp is farther in the 271 // future, the buffer won't be acquired, and PRESENT_LATER will be 272 // returned. The presentation time is in nanoseconds, and the time base 273 // is CLOCK_MONOTONIC. 274 virtual status_t acquireBuffer(BufferItem* buffer, nsecs_t presentWhen); 275 276 // See IGraphicBufferConsumer::detachBuffer 277 virtual status_t detachConsumerBuffer(int slot); 278 279 // See IGraphicBufferConsumer::attachBuffer 280 virtual status_t attachConsumerBuffer(int* slot, 281 const sp<GraphicBuffer>& buffer); 282 283 // releaseBuffer releases a buffer slot from the consumer back to the 284 // BufferQueue. This may be done while the buffer's contents are still 285 // being accessed. The fence will signal when the buffer is no longer 286 // in use. frameNumber is used to indentify the exact buffer returned. 287 // 288 // If releaseBuffer returns STALE_BUFFER_SLOT, then the consumer must free 289 // any references to the just-released buffer that it might have, as if it 290 // had received a onBuffersReleased() call with a mask set for the released 291 // buffer. 292 // 293 // Note that the dependencies on EGL will be removed once we switch to using 294 // the Android HW Sync HAL. 295 virtual status_t releaseBuffer(int buf, uint64_t frameNumber, 296 EGLDisplay display, EGLSyncKHR fence, 297 const sp<Fence>& releaseFence); 298 299 // consumerConnect connects a consumer to the BufferQueue. Only one 300 // consumer may be connected, and when that consumer disconnects the 301 // BufferQueue is placed into the "abandoned" state, causing most 302 // interactions with the BufferQueue by the producer to fail. 303 // controlledByApp indicates whether the consumer is controlled by 304 // the application. 305 // 306 // consumer may not be NULL. 307 virtual status_t consumerConnect(const sp<IConsumerListener>& consumer, bool controlledByApp); 308 309 // consumerDisconnect disconnects a consumer from the BufferQueue. All 310 // buffers will be freed and the BufferQueue is placed in the "abandoned" 311 // state, causing most interactions with the BufferQueue by the producer to 312 // fail. 313 virtual status_t consumerDisconnect(); 314 315 // getReleasedBuffers sets the value pointed to by slotMask to a bit mask 316 // indicating which buffer slots have been released by the BufferQueue 317 // but have not yet been released by the consumer. 318 // 319 // This should be called from the onBuffersReleased() callback. 320 virtual status_t getReleasedBuffers(uint32_t* slotMask); 321 322 // setDefaultBufferSize is used to set the size of buffers returned by 323 // dequeueBuffer when a width and height of zero is requested. Default 324 // is 1x1. 325 virtual status_t setDefaultBufferSize(uint32_t w, uint32_t h); 326 327 // setDefaultMaxBufferCount sets the default value for the maximum buffer 328 // count (the initial default is 2). If the producer has requested a 329 // buffer count using setBufferCount, the default buffer count will only 330 // take effect if the producer sets the count back to zero. 331 // 332 // The count must be between 2 and NUM_BUFFER_SLOTS, inclusive. 333 virtual status_t setDefaultMaxBufferCount(int bufferCount); 334 335 // disableAsyncBuffer disables the extra buffer used in async mode 336 // (when both producer and consumer have set their "isControlledByApp" 337 // flag) and has dequeueBuffer() return WOULD_BLOCK instead. 338 // 339 // This can only be called before consumerConnect(). 340 virtual status_t disableAsyncBuffer(); 341 342 // setMaxAcquiredBufferCount sets the maximum number of buffers that can 343 // be acquired by the consumer at one time (default 1). This call will 344 // fail if a producer is connected to the BufferQueue. 345 virtual status_t setMaxAcquiredBufferCount(int maxAcquiredBuffers); 346 347 // setConsumerName sets the name used in logging 348 virtual void setConsumerName(const String8& name); 349 350 // setDefaultBufferFormat allows the BufferQueue to create 351 // GraphicBuffers of a defaultFormat if no format is specified 352 // in dequeueBuffer. Formats are enumerated in graphics.h; the 353 // initial default is HAL_PIXEL_FORMAT_RGBA_8888. 354 virtual status_t setDefaultBufferFormat(uint32_t defaultFormat); 355 356 // setConsumerUsageBits will turn on additional usage bits for dequeueBuffer. 357 // These are merged with the bits passed to dequeueBuffer. The values are 358 // enumerated in gralloc.h, e.g. GRALLOC_USAGE_HW_RENDER; the default is 0. 359 virtual status_t setConsumerUsageBits(uint32_t usage); 360 361 // setTransformHint bakes in rotation to buffers so overlays can be used. 362 // The values are enumerated in window.h, e.g. 363 // NATIVE_WINDOW_TRANSFORM_ROT_90. The default is 0 (no transform). 364 virtual status_t setTransformHint(uint32_t hint); 365 366 // Retrieve the BufferQueue's sideband stream, if any. 367 virtual sp<NativeHandle> getSidebandStream() const; 368 369 // dump our state in a String 370 virtual void dump(String8& result, const char* prefix) const; 371 372private: 373 sp<BufferQueueProducer> mProducer; 374 sp<BufferQueueConsumer> mConsumer; 375}; 376 377// ---------------------------------------------------------------------------- 378}; // namespace android 379 380#endif // ANDROID_GUI_BUFFERQUEUE_H 381