BufferQueueProducer.cpp revision d9822a3843017444364899afc3c23fb5be6b9cb9
1/*
2 * Copyright 2014 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#define LOG_TAG "BufferQueueProducer"
18#define ATRACE_TAG ATRACE_TAG_GRAPHICS
19//#define LOG_NDEBUG 0
20
21#define EGL_EGLEXT_PROTOTYPES
22
23#include <gui/BufferItem.h>
24#include <gui/BufferQueueCore.h>
25#include <gui/BufferQueueProducer.h>
26#include <gui/IConsumerListener.h>
27#include <gui/IGraphicBufferAlloc.h>
28#include <gui/IProducerListener.h>
29
30#include <utils/Log.h>
31#include <utils/Trace.h>
32
33namespace android {
34
35BufferQueueProducer::BufferQueueProducer(const sp<BufferQueueCore>& core) :
36    mCore(core),
37    mSlots(core->mSlots),
38    mConsumerName() {}
39
40BufferQueueProducer::~BufferQueueProducer() {}
41
42status_t BufferQueueProducer::requestBuffer(int slot, sp<GraphicBuffer>* buf) {
43    ATRACE_CALL();
44    BQ_LOGV("requestBuffer: slot %d", slot);
45    Mutex::Autolock lock(mCore->mMutex);
46
47    if (mCore->mIsAbandoned) {
48        BQ_LOGE("requestBuffer: BufferQueue has been abandoned");
49        return NO_INIT;
50    }
51
52    if (slot < 0 || slot >= BufferQueueDefs::NUM_BUFFER_SLOTS) {
53        BQ_LOGE("requestBuffer: slot index %d out of range [0, %d)",
54                slot, BufferQueueDefs::NUM_BUFFER_SLOTS);
55        return BAD_VALUE;
56    } else if (mSlots[slot].mBufferState != BufferSlot::DEQUEUED) {
57        BQ_LOGE("requestBuffer: slot %d is not owned by the producer "
58                "(state = %d)", slot, mSlots[slot].mBufferState);
59        return BAD_VALUE;
60    }
61
62    mSlots[slot].mRequestBufferCalled = true;
63    *buf = mSlots[slot].mGraphicBuffer;
64    return NO_ERROR;
65}
66
67status_t BufferQueueProducer::setBufferCount(int bufferCount) {
68    ATRACE_CALL();
69    BQ_LOGV("setBufferCount: count = %d", bufferCount);
70
71    sp<IConsumerListener> listener;
72    { // Autolock scope
73        Mutex::Autolock lock(mCore->mMutex);
74
75        if (mCore->mIsAbandoned) {
76            BQ_LOGE("setBufferCount: BufferQueue has been abandoned");
77            return NO_INIT;
78        }
79
80        if (bufferCount > BufferQueueDefs::NUM_BUFFER_SLOTS) {
81            BQ_LOGE("setBufferCount: bufferCount %d too large (max %d)",
82                    bufferCount, BufferQueueDefs::NUM_BUFFER_SLOTS);
83            return BAD_VALUE;
84        }
85
86        // There must be no dequeued buffers when changing the buffer count.
87        for (int s = 0; s < BufferQueueDefs::NUM_BUFFER_SLOTS; ++s) {
88            if (mSlots[s].mBufferState == BufferSlot::DEQUEUED) {
89                BQ_LOGE("setBufferCount: buffer owned by producer");
90                return BAD_VALUE;
91            }
92        }
93
94        if (bufferCount == 0) {
95            mCore->mOverrideMaxBufferCount = 0;
96            mCore->mDequeueCondition.broadcast();
97            return NO_ERROR;
98        }
99
100        const int minBufferSlots = mCore->getMinMaxBufferCountLocked(false);
101        if (bufferCount < minBufferSlots) {
102            BQ_LOGE("setBufferCount: requested buffer count %d is less than "
103                    "minimum %d", bufferCount, minBufferSlots);
104            return BAD_VALUE;
105        }
106
107        // Here we are guaranteed that the producer doesn't have any dequeued
108        // buffers and will release all of its buffer references. We don't
109        // clear the queue, however, so that currently queued buffers still
110        // get displayed.
111        mCore->freeAllBuffersLocked();
112        mCore->mOverrideMaxBufferCount = bufferCount;
113        mCore->mDequeueCondition.broadcast();
114        listener = mCore->mConsumerListener;
115    } // Autolock scope
116
117    // Call back without lock held
118    if (listener != NULL) {
119        listener->onBuffersReleased();
120    }
121
122    return NO_ERROR;
123}
124
125status_t BufferQueueProducer::waitForFreeSlotThenRelock(const char* caller,
126        bool async, int* found, status_t* returnFlags) const {
127    bool tryAgain = true;
128    while (tryAgain) {
129        if (mCore->mIsAbandoned) {
130            BQ_LOGE("%s: BufferQueue has been abandoned", caller);
131            return NO_INIT;
132        }
133
134        const int maxBufferCount = mCore->getMaxBufferCountLocked(async);
135        if (async && mCore->mOverrideMaxBufferCount) {
136            // FIXME: Some drivers are manually setting the buffer count
137            // (which they shouldn't), so we do this extra test here to
138            // handle that case. This is TEMPORARY until we get this fixed.
139            if (mCore->mOverrideMaxBufferCount < maxBufferCount) {
140                BQ_LOGE("%s: async mode is invalid with buffer count override",
141                        caller);
142                return BAD_VALUE;
143            }
144        }
145
146        // Free up any buffers that are in slots beyond the max buffer count
147        for (int s = maxBufferCount; s < BufferQueueDefs::NUM_BUFFER_SLOTS; ++s) {
148            assert(mSlots[s].mBufferState == BufferSlot::FREE);
149            if (mSlots[s].mGraphicBuffer != NULL) {
150                mCore->freeBufferLocked(s);
151                *returnFlags |= RELEASE_ALL_BUFFERS;
152            }
153        }
154
155        // Look for a free buffer to give to the client
156        *found = BufferQueueCore::INVALID_BUFFER_SLOT;
157        int dequeuedCount = 0;
158        int acquiredCount = 0;
159        for (int s = 0; s < maxBufferCount; ++s) {
160            switch (mSlots[s].mBufferState) {
161                case BufferSlot::DEQUEUED:
162                    ++dequeuedCount;
163                    break;
164                case BufferSlot::ACQUIRED:
165                    ++acquiredCount;
166                    break;
167                case BufferSlot::FREE:
168                    // We return the oldest of the free buffers to avoid
169                    // stalling the producer if possible, since the consumer
170                    // may still have pending reads of in-flight buffers
171                    if (*found == BufferQueueCore::INVALID_BUFFER_SLOT ||
172                            mSlots[s].mFrameNumber < mSlots[*found].mFrameNumber) {
173                        *found = s;
174                    }
175                    break;
176                default:
177                    break;
178            }
179        }
180
181        // Producers are not allowed to dequeue more than one buffer if they
182        // did not set a buffer count
183        if (!mCore->mOverrideMaxBufferCount && dequeuedCount) {
184            BQ_LOGE("%s: can't dequeue multiple buffers without setting the "
185                    "buffer count", caller);
186            return INVALID_OPERATION;
187        }
188
189        // See whether a buffer has been queued since the last
190        // setBufferCount so we know whether to perform the min undequeued
191        // buffers check below
192        if (mCore->mBufferHasBeenQueued) {
193            // Make sure the producer is not trying to dequeue more buffers
194            // than allowed
195            const int newUndequeuedCount =
196                maxBufferCount - (dequeuedCount + 1);
197            const int minUndequeuedCount =
198                mCore->getMinUndequeuedBufferCountLocked(async);
199            if (newUndequeuedCount < minUndequeuedCount) {
200                BQ_LOGE("%s: min undequeued buffer count (%d) exceeded "
201                        "(dequeued=%d undequeued=%d)",
202                        caller, minUndequeuedCount,
203                        dequeuedCount, newUndequeuedCount);
204                return INVALID_OPERATION;
205            }
206        }
207
208        // If no buffer is found, wait for a buffer to be released or for
209        // the max buffer count to change
210        tryAgain = (*found == BufferQueueCore::INVALID_BUFFER_SLOT);
211        if (tryAgain) {
212            // Return an error if we're in non-blocking mode (producer and
213            // consumer are controlled by the application).
214            // However, the consumer is allowed to briefly acquire an extra
215            // buffer (which could cause us to have to wait here), which is
216            // okay, since it is only used to implement an atomic acquire +
217            // release (e.g., in GLConsumer::updateTexImage())
218            if (mCore->mDequeueBufferCannotBlock &&
219                    (acquiredCount <= mCore->mMaxAcquiredBufferCount)) {
220                return WOULD_BLOCK;
221            }
222            mCore->mDequeueCondition.wait(mCore->mMutex);
223        }
224    } // while (tryAgain)
225
226    return NO_ERROR;
227}
228
229status_t BufferQueueProducer::dequeueBuffer(int *outSlot,
230        sp<android::Fence> *outFence, bool async,
231        uint32_t width, uint32_t height, uint32_t format, uint32_t usage) {
232    ATRACE_CALL();
233    { // Autolock scope
234        Mutex::Autolock lock(mCore->mMutex);
235        mConsumerName = mCore->mConsumerName;
236    } // Autolock scope
237
238    BQ_LOGV("dequeueBuffer: async=%s w=%u h=%u format=%#x, usage=%#x",
239            async ? "true" : "false", width, height, format, usage);
240
241    if ((width && !height) || (!width && height)) {
242        BQ_LOGE("dequeueBuffer: invalid size: w=%u h=%u", width, height);
243        return BAD_VALUE;
244    }
245
246    status_t returnFlags = NO_ERROR;
247    EGLDisplay eglDisplay = EGL_NO_DISPLAY;
248    EGLSyncKHR eglFence = EGL_NO_SYNC_KHR;
249    bool attachedByConsumer = false;
250
251    { // Autolock scope
252        Mutex::Autolock lock(mCore->mMutex);
253
254        if (format == 0) {
255            format = mCore->mDefaultBufferFormat;
256        }
257
258        // Enable the usage bits the consumer requested
259        usage |= mCore->mConsumerUsageBits;
260
261        int found;
262        status_t status = waitForFreeSlotThenRelock("dequeueBuffer", async,
263                &found, &returnFlags);
264        if (status != NO_ERROR) {
265            return status;
266        }
267
268        // This should not happen
269        if (found == BufferQueueCore::INVALID_BUFFER_SLOT) {
270            BQ_LOGE("dequeueBuffer: no available buffer slots");
271            return -EBUSY;
272        }
273
274        *outSlot = found;
275        ATRACE_BUFFER_INDEX(found);
276
277        attachedByConsumer = mSlots[found].mAttachedByConsumer;
278
279        const bool useDefaultSize = !width && !height;
280        if (useDefaultSize) {
281            width = mCore->mDefaultWidth;
282            height = mCore->mDefaultHeight;
283        }
284
285        mSlots[found].mBufferState = BufferSlot::DEQUEUED;
286
287        const sp<GraphicBuffer>& buffer(mSlots[found].mGraphicBuffer);
288        if ((buffer == NULL) ||
289                (static_cast<uint32_t>(buffer->width) != width) ||
290                (static_cast<uint32_t>(buffer->height) != height) ||
291                (static_cast<uint32_t>(buffer->format) != format) ||
292                ((static_cast<uint32_t>(buffer->usage) & usage) != usage))
293        {
294            mSlots[found].mAcquireCalled = false;
295            mSlots[found].mGraphicBuffer = NULL;
296            mSlots[found].mRequestBufferCalled = false;
297            mSlots[found].mEglDisplay = EGL_NO_DISPLAY;
298            mSlots[found].mEglFence = EGL_NO_SYNC_KHR;
299            mSlots[found].mFence = Fence::NO_FENCE;
300
301            returnFlags |= BUFFER_NEEDS_REALLOCATION;
302        }
303
304        if (CC_UNLIKELY(mSlots[found].mFence == NULL)) {
305            BQ_LOGE("dequeueBuffer: about to return a NULL fence - "
306                    "slot=%d w=%d h=%d format=%u",
307                    found, buffer->width, buffer->height, buffer->format);
308        }
309
310        eglDisplay = mSlots[found].mEglDisplay;
311        eglFence = mSlots[found].mEglFence;
312        *outFence = mSlots[found].mFence;
313        mSlots[found].mEglFence = EGL_NO_SYNC_KHR;
314        mSlots[found].mFence = Fence::NO_FENCE;
315    } // Autolock scope
316
317    if (returnFlags & BUFFER_NEEDS_REALLOCATION) {
318        status_t error;
319        sp<GraphicBuffer> graphicBuffer(mCore->mAllocator->createGraphicBuffer(
320                    width, height, format, usage, &error));
321        if (graphicBuffer == NULL) {
322            BQ_LOGE("dequeueBuffer: createGraphicBuffer failed");
323            return error;
324        }
325
326        { // Autolock scope
327            Mutex::Autolock lock(mCore->mMutex);
328
329            if (mCore->mIsAbandoned) {
330                BQ_LOGE("dequeueBuffer: BufferQueue has been abandoned");
331                return NO_INIT;
332            }
333
334            mSlots[*outSlot].mFrameNumber = UINT32_MAX;
335            mSlots[*outSlot].mGraphicBuffer = graphicBuffer;
336        } // Autolock scope
337    }
338
339    if (attachedByConsumer) {
340        returnFlags |= BUFFER_NEEDS_REALLOCATION;
341    }
342
343    if (eglFence != EGL_NO_SYNC_KHR) {
344        EGLint result = eglClientWaitSyncKHR(eglDisplay, eglFence, 0,
345                1000000000);
346        // If something goes wrong, log the error, but return the buffer without
347        // synchronizing access to it. It's too late at this point to abort the
348        // dequeue operation.
349        if (result == EGL_FALSE) {
350            BQ_LOGE("dequeueBuffer: error %#x waiting for fence",
351                    eglGetError());
352        } else if (result == EGL_TIMEOUT_EXPIRED_KHR) {
353            BQ_LOGE("dequeueBuffer: timeout waiting for fence");
354        }
355        eglDestroySyncKHR(eglDisplay, eglFence);
356    }
357
358    BQ_LOGV("dequeueBuffer: returning slot=%d/%llu buf=%p flags=%#x", *outSlot,
359            mSlots[*outSlot].mFrameNumber,
360            mSlots[*outSlot].mGraphicBuffer->handle, returnFlags);
361
362    return returnFlags;
363}
364
365status_t BufferQueueProducer::detachBuffer(int slot) {
366    ATRACE_CALL();
367    ATRACE_BUFFER_INDEX(slot);
368    BQ_LOGV("detachBuffer(P): slot %d", slot);
369    Mutex::Autolock lock(mCore->mMutex);
370
371    if (mCore->mIsAbandoned) {
372        BQ_LOGE("detachBuffer(P): BufferQueue has been abandoned");
373        return NO_INIT;
374    }
375
376    if (slot < 0 || slot >= BufferQueueDefs::NUM_BUFFER_SLOTS) {
377        BQ_LOGE("detachBuffer(P): slot index %d out of range [0, %d)",
378                slot, BufferQueueDefs::NUM_BUFFER_SLOTS);
379        return BAD_VALUE;
380    } else if (mSlots[slot].mBufferState != BufferSlot::DEQUEUED) {
381        BQ_LOGE("detachBuffer(P): slot %d is not owned by the producer "
382                "(state = %d)", slot, mSlots[slot].mBufferState);
383        return BAD_VALUE;
384    } else if (!mSlots[slot].mRequestBufferCalled) {
385        BQ_LOGE("detachBuffer(P): buffer in slot %d has not been requested",
386                slot);
387        return BAD_VALUE;
388    }
389
390    mCore->freeBufferLocked(slot);
391    mCore->mDequeueCondition.broadcast();
392
393    return NO_ERROR;
394}
395
396status_t BufferQueueProducer::detachNextBuffer(sp<GraphicBuffer>* outBuffer,
397        sp<Fence>* outFence) {
398    ATRACE_CALL();
399
400    if (outBuffer == NULL) {
401        BQ_LOGE("detachNextBuffer: outBuffer must not be NULL");
402        return BAD_VALUE;
403    } else if (outFence == NULL) {
404        BQ_LOGE("detachNextBuffer: outFence must not be NULL");
405        return BAD_VALUE;
406    }
407
408    Mutex::Autolock lock(mCore->mMutex);
409
410    if (mCore->mIsAbandoned) {
411        BQ_LOGE("detachNextBuffer: BufferQueue has been abandoned");
412        return NO_INIT;
413    }
414
415    // Find the oldest valid slot
416    int found = BufferQueueCore::INVALID_BUFFER_SLOT;
417    for (int s = 0; s < BufferQueueDefs::NUM_BUFFER_SLOTS; ++s) {
418        if (mSlots[s].mBufferState == BufferSlot::FREE &&
419                mSlots[s].mGraphicBuffer != NULL) {
420            if (found == BufferQueueCore::INVALID_BUFFER_SLOT ||
421                    mSlots[s].mFrameNumber < mSlots[found].mFrameNumber) {
422                found = s;
423            }
424        }
425    }
426
427    if (found == BufferQueueCore::INVALID_BUFFER_SLOT) {
428        return NO_MEMORY;
429    }
430
431    BQ_LOGV("detachNextBuffer detached slot %d", found);
432
433    *outBuffer = mSlots[found].mGraphicBuffer;
434    *outFence = mSlots[found].mFence;
435    mCore->freeBufferLocked(found);
436
437    return NO_ERROR;
438}
439
440status_t BufferQueueProducer::attachBuffer(int* outSlot,
441        const sp<android::GraphicBuffer>& buffer) {
442    ATRACE_CALL();
443
444    if (outSlot == NULL) {
445        BQ_LOGE("attachBuffer(P): outSlot must not be NULL");
446        return BAD_VALUE;
447    } else if (buffer == NULL) {
448        BQ_LOGE("attachBuffer(P): cannot attach NULL buffer");
449        return BAD_VALUE;
450    }
451
452    Mutex::Autolock lock(mCore->mMutex);
453
454    status_t returnFlags = NO_ERROR;
455    int found;
456    // TODO: Should we provide an async flag to attachBuffer? It seems
457    // unlikely that buffers which we are attaching to a BufferQueue will
458    // be asynchronous (droppable), but it may not be impossible.
459    status_t status = waitForFreeSlotThenRelock("attachBuffer(P)", false,
460            &found, &returnFlags);
461    if (status != NO_ERROR) {
462        return status;
463    }
464
465    // This should not happen
466    if (found == BufferQueueCore::INVALID_BUFFER_SLOT) {
467        BQ_LOGE("attachBuffer(P): no available buffer slots");
468        return -EBUSY;
469    }
470
471    *outSlot = found;
472    ATRACE_BUFFER_INDEX(*outSlot);
473    BQ_LOGV("attachBuffer(P): returning slot %d flags=%#x",
474            *outSlot, returnFlags);
475
476    mSlots[*outSlot].mGraphicBuffer = buffer;
477    mSlots[*outSlot].mBufferState = BufferSlot::DEQUEUED;
478    mSlots[*outSlot].mEglFence = EGL_NO_SYNC_KHR;
479    mSlots[*outSlot].mFence = Fence::NO_FENCE;
480    mSlots[*outSlot].mRequestBufferCalled = true;
481
482    return returnFlags;
483}
484
485status_t BufferQueueProducer::queueBuffer(int slot,
486        const QueueBufferInput &input, QueueBufferOutput *output) {
487    ATRACE_CALL();
488    ATRACE_BUFFER_INDEX(slot);
489
490    int64_t timestamp;
491    bool isAutoTimestamp;
492    Rect crop;
493    int scalingMode;
494    uint32_t transform;
495    bool async;
496    sp<Fence> fence;
497    input.deflate(&timestamp, &isAutoTimestamp, &crop, &scalingMode, &transform,
498            &async, &fence);
499
500    if (fence == NULL) {
501        BQ_LOGE("queueBuffer: fence is NULL");
502        return BAD_VALUE;
503    }
504
505    switch (scalingMode) {
506        case NATIVE_WINDOW_SCALING_MODE_FREEZE:
507        case NATIVE_WINDOW_SCALING_MODE_SCALE_TO_WINDOW:
508        case NATIVE_WINDOW_SCALING_MODE_SCALE_CROP:
509        case NATIVE_WINDOW_SCALING_MODE_NO_SCALE_CROP:
510            break;
511        default:
512            BQ_LOGE("queueBuffer: unknown scaling mode %d", scalingMode);
513            return BAD_VALUE;
514    }
515
516    sp<IConsumerListener> listener;
517    { // Autolock scope
518        Mutex::Autolock lock(mCore->mMutex);
519
520        if (mCore->mIsAbandoned) {
521            BQ_LOGE("queueBuffer: BufferQueue has been abandoned");
522            return NO_INIT;
523        }
524
525        const int maxBufferCount = mCore->getMaxBufferCountLocked(async);
526        if (async && mCore->mOverrideMaxBufferCount) {
527            // FIXME: Some drivers are manually setting the buffer count
528            // (which they shouldn't), so we do this extra test here to
529            // handle that case. This is TEMPORARY until we get this fixed.
530            if (mCore->mOverrideMaxBufferCount < maxBufferCount) {
531                BQ_LOGE("queueBuffer: async mode is invalid with "
532                        "buffer count override");
533                return BAD_VALUE;
534            }
535        }
536
537        if (slot < 0 || slot >= maxBufferCount) {
538            BQ_LOGE("queueBuffer: slot index %d out of range [0, %d)",
539                    slot, maxBufferCount);
540            return BAD_VALUE;
541        } else if (mSlots[slot].mBufferState != BufferSlot::DEQUEUED) {
542            BQ_LOGE("queueBuffer: slot %d is not owned by the producer "
543                    "(state = %d)", slot, mSlots[slot].mBufferState);
544            return BAD_VALUE;
545        } else if (!mSlots[slot].mRequestBufferCalled) {
546            BQ_LOGE("queueBuffer: slot %d was queued without requesting "
547                    "a buffer", slot);
548            return BAD_VALUE;
549        }
550
551        BQ_LOGV("queueBuffer: slot=%d/%llu time=%llu crop=[%d,%d,%d,%d] "
552                "transform=%#x scale=%s",
553                slot, mCore->mFrameCounter + 1, timestamp,
554                crop.left, crop.top, crop.right, crop.bottom,
555                transform, BufferItem::scalingModeName(scalingMode));
556
557        const sp<GraphicBuffer>& graphicBuffer(mSlots[slot].mGraphicBuffer);
558        Rect bufferRect(graphicBuffer->getWidth(), graphicBuffer->getHeight());
559        Rect croppedRect;
560        crop.intersect(bufferRect, &croppedRect);
561        if (croppedRect != crop) {
562            BQ_LOGE("queueBuffer: crop rect is not contained within the "
563                    "buffer in slot %d", slot);
564            return BAD_VALUE;
565        }
566
567        mSlots[slot].mFence = fence;
568        mSlots[slot].mBufferState = BufferSlot::QUEUED;
569        ++mCore->mFrameCounter;
570        mSlots[slot].mFrameNumber = mCore->mFrameCounter;
571
572        BufferItem item;
573        item.mAcquireCalled = mSlots[slot].mAcquireCalled;
574        item.mGraphicBuffer = mSlots[slot].mGraphicBuffer;
575        item.mCrop = crop;
576        item.mTransform = transform & ~NATIVE_WINDOW_TRANSFORM_INVERSE_DISPLAY;
577        item.mTransformToDisplayInverse =
578                bool(transform & NATIVE_WINDOW_TRANSFORM_INVERSE_DISPLAY);
579        item.mScalingMode = scalingMode;
580        item.mTimestamp = timestamp;
581        item.mIsAutoTimestamp = isAutoTimestamp;
582        item.mFrameNumber = mCore->mFrameCounter;
583        item.mSlot = slot;
584        item.mFence = fence;
585        item.mIsDroppable = mCore->mDequeueBufferCannotBlock || async;
586
587        if (mCore->mQueue.empty()) {
588            // When the queue is empty, we can ignore mDequeueBufferCannotBlock
589            // and simply queue this buffer
590            mCore->mQueue.push_back(item);
591            listener = mCore->mConsumerListener;
592        } else {
593            // When the queue is not empty, we need to look at the front buffer
594            // state to see if we need to replace it
595            BufferQueueCore::Fifo::iterator front(mCore->mQueue.begin());
596            if (front->mIsDroppable) {
597                // If the front queued buffer is still being tracked, we first
598                // mark it as freed
599                if (mCore->stillTracking(front)) {
600                    mSlots[front->mSlot].mBufferState = BufferSlot::FREE;
601                    // Reset the frame number of the freed buffer so that it is
602                    // the first in line to be dequeued again
603                    mSlots[front->mSlot].mFrameNumber = 0;
604                }
605                // Overwrite the droppable buffer with the incoming one
606                *front = item;
607            } else {
608                mCore->mQueue.push_back(item);
609                listener = mCore->mConsumerListener;
610            }
611        }
612
613        mCore->mBufferHasBeenQueued = true;
614        mCore->mDequeueCondition.broadcast();
615
616        output->inflate(mCore->mDefaultWidth, mCore->mDefaultHeight,
617                mCore->mTransformHint, mCore->mQueue.size());
618
619        ATRACE_INT(mCore->mConsumerName.string(), mCore->mQueue.size());
620    } // Autolock scope
621
622    // Call back without lock held
623    if (listener != NULL) {
624        listener->onFrameAvailable();
625    }
626
627    return NO_ERROR;
628}
629
630void BufferQueueProducer::cancelBuffer(int slot, const sp<Fence>& fence) {
631    ATRACE_CALL();
632    BQ_LOGV("cancelBuffer: slot %d", slot);
633    Mutex::Autolock lock(mCore->mMutex);
634
635    if (mCore->mIsAbandoned) {
636        BQ_LOGE("cancelBuffer: BufferQueue has been abandoned");
637        return;
638    }
639
640    if (slot < 0 || slot >= BufferQueueDefs::NUM_BUFFER_SLOTS) {
641        BQ_LOGE("cancelBuffer: slot index %d out of range [0, %d)",
642                slot, BufferQueueDefs::NUM_BUFFER_SLOTS);
643        return;
644    } else if (mSlots[slot].mBufferState != BufferSlot::DEQUEUED) {
645        BQ_LOGE("cancelBuffer: slot %d is not owned by the producer "
646                "(state = %d)", slot, mSlots[slot].mBufferState);
647        return;
648    } else if (fence == NULL) {
649        BQ_LOGE("cancelBuffer: fence is NULL");
650        return;
651    }
652
653    mSlots[slot].mBufferState = BufferSlot::FREE;
654    mSlots[slot].mFrameNumber = 0;
655    mSlots[slot].mFence = fence;
656    mCore->mDequeueCondition.broadcast();
657}
658
659int BufferQueueProducer::query(int what, int *outValue) {
660    ATRACE_CALL();
661    Mutex::Autolock lock(mCore->mMutex);
662
663    if (outValue == NULL) {
664        BQ_LOGE("query: outValue was NULL");
665        return BAD_VALUE;
666    }
667
668    if (mCore->mIsAbandoned) {
669        BQ_LOGE("query: BufferQueue has been abandoned");
670        return NO_INIT;
671    }
672
673    int value;
674    switch (what) {
675        case NATIVE_WINDOW_WIDTH:
676            value = mCore->mDefaultWidth;
677            break;
678        case NATIVE_WINDOW_HEIGHT:
679            value = mCore->mDefaultHeight;
680            break;
681        case NATIVE_WINDOW_FORMAT:
682            value = mCore->mDefaultBufferFormat;
683            break;
684        case NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS:
685            value = mCore->getMinUndequeuedBufferCountLocked(false);
686            break;
687        case NATIVE_WINDOW_CONSUMER_RUNNING_BEHIND:
688            value = (mCore->mQueue.size() > 1);
689            break;
690        case NATIVE_WINDOW_CONSUMER_USAGE_BITS:
691            value = mCore->mConsumerUsageBits;
692            break;
693        default:
694            return BAD_VALUE;
695    }
696
697    BQ_LOGV("query: %d? %d", what, value);
698    *outValue = value;
699    return NO_ERROR;
700}
701
702status_t BufferQueueProducer::connect(const sp<IProducerListener>& listener,
703        int api, bool producerControlledByApp, QueueBufferOutput *output) {
704    ATRACE_CALL();
705    Mutex::Autolock lock(mCore->mMutex);
706    mConsumerName = mCore->mConsumerName;
707    BQ_LOGV("connect(P): api=%d producerControlledByApp=%s", api,
708            producerControlledByApp ? "true" : "false");
709
710    // If we disconnect and reconnect quickly, we can be in a state where our
711    // slots are empty but we have many buffers in the queue. This can cause us
712    // to run out of memory if we outrun the consumer. Wait here if it looks
713    // like we have too many buffers queued up.
714    while (true) {
715        if (mCore->mIsAbandoned) {
716            BQ_LOGE("connect(P): BufferQueue has been abandoned");
717            return NO_INIT;
718        }
719
720        if (mCore->mConsumerListener == NULL) {
721            BQ_LOGE("connect(P): BufferQueue has no consumer");
722            return NO_INIT;
723        }
724
725        if (output == NULL) {
726            BQ_LOGE("connect(P): output was NULL");
727            return BAD_VALUE;
728        }
729
730        if (mCore->mConnectedApi != BufferQueueCore::NO_CONNECTED_API) {
731            BQ_LOGE("connect(P): already connected (cur=%d req=%d)",
732                    mCore->mConnectedApi, api);
733            return BAD_VALUE;
734        }
735
736        size_t maxBufferCount = mCore->getMaxBufferCountLocked(false);
737        if (mCore->mQueue.size() <= maxBufferCount) {
738            // The queue size seems small enough to proceed
739            // TODO: Make this bound tighter?
740            break;
741        }
742
743        BQ_LOGV("connect(P): queue size is %d, waiting", mCore->mQueue.size());
744        mCore->mDequeueCondition.wait(mCore->mMutex);
745    }
746
747    int status = NO_ERROR;
748    switch (api) {
749        case NATIVE_WINDOW_API_EGL:
750        case NATIVE_WINDOW_API_CPU:
751        case NATIVE_WINDOW_API_MEDIA:
752        case NATIVE_WINDOW_API_CAMERA:
753            mCore->mConnectedApi = api;
754            output->inflate(mCore->mDefaultWidth, mCore->mDefaultHeight,
755                    mCore->mTransformHint, mCore->mQueue.size());
756
757            // Set up a death notification so that we can disconnect
758            // automatically if the remote producer dies
759            if (listener != NULL &&
760                    listener->asBinder()->remoteBinder() != NULL) {
761                status = listener->asBinder()->linkToDeath(
762                        static_cast<IBinder::DeathRecipient*>(this));
763                if (status != NO_ERROR) {
764                    BQ_LOGE("connect(P): linkToDeath failed: %s (%d)",
765                            strerror(-status), status);
766                }
767            }
768            mCore->mConnectedProducerListener = listener;
769            break;
770        default:
771            BQ_LOGE("connect(P): unknown API %d", api);
772            status = BAD_VALUE;
773            break;
774    }
775
776    mCore->mBufferHasBeenQueued = false;
777    mCore->mDequeueBufferCannotBlock =
778            mCore->mConsumerControlledByApp && producerControlledByApp;
779
780    return status;
781}
782
783status_t BufferQueueProducer::disconnect(int api) {
784    ATRACE_CALL();
785    BQ_LOGV("disconnect(P): api %d", api);
786
787    int status = NO_ERROR;
788    sp<IConsumerListener> listener;
789    { // Autolock scope
790        Mutex::Autolock lock(mCore->mMutex);
791
792        if (mCore->mIsAbandoned) {
793            // It's not really an error to disconnect after the surface has
794            // been abandoned; it should just be a no-op.
795            return NO_ERROR;
796        }
797
798        switch (api) {
799            case NATIVE_WINDOW_API_EGL:
800            case NATIVE_WINDOW_API_CPU:
801            case NATIVE_WINDOW_API_MEDIA:
802            case NATIVE_WINDOW_API_CAMERA:
803                if (mCore->mConnectedApi == api) {
804                    mCore->freeAllBuffersLocked();
805
806                    // Remove our death notification callback if we have one
807                    if (mCore->mConnectedProducerListener != NULL) {
808                        sp<IBinder> token =
809                                mCore->mConnectedProducerListener->asBinder();
810                        // This can fail if we're here because of the death
811                        // notification, but we just ignore it
812                        token->unlinkToDeath(
813                                static_cast<IBinder::DeathRecipient*>(this));
814                    }
815                    mCore->mConnectedProducerListener = NULL;
816                    mCore->mConnectedApi = BufferQueueCore::NO_CONNECTED_API;
817                    mCore->mSidebandStream.clear();
818                    mCore->mDequeueCondition.broadcast();
819                    listener = mCore->mConsumerListener;
820                } else {
821                    BQ_LOGE("disconnect(P): connected to another API "
822                            "(cur=%d req=%d)", mCore->mConnectedApi, api);
823                    status = BAD_VALUE;
824                }
825                break;
826            default:
827                BQ_LOGE("disconnect(P): unknown API %d", api);
828                status = BAD_VALUE;
829                break;
830        }
831    } // Autolock scope
832
833    // Call back without lock held
834    if (listener != NULL) {
835        listener->onBuffersReleased();
836    }
837
838    return status;
839}
840
841status_t BufferQueueProducer::setSidebandStream(const sp<NativeHandle>& stream) {
842    sp<IConsumerListener> listener;
843    { // Autolock scope
844        Mutex::Autolock _l(mCore->mMutex);
845        mCore->mSidebandStream = stream;
846        listener = mCore->mConsumerListener;
847    } // Autolock scope
848
849    if (listener != NULL) {
850        listener->onSidebandStreamChanged();
851    }
852    return NO_ERROR;
853}
854
855void BufferQueueProducer::binderDied(const wp<android::IBinder>& /* who */) {
856    // If we're here, it means that a producer we were connected to died.
857    // We're guaranteed that we are still connected to it because we remove
858    // this callback upon disconnect. It's therefore safe to read mConnectedApi
859    // without synchronization here.
860    int api = mCore->mConnectedApi;
861    disconnect(api);
862}
863
864} // namespace android
865