Merge "BufferQueueProducer: add detachNextBuffer"

3 files changed, 99 insertions, 0 deletions

diff --git a/libs/gui/BufferQueue.cpp b/libs/gui/BufferQueue.cpp
index d04b67d..da980a7 100644
--- a/libs/gui/BufferQueue.cpp
+++ b/libs/gui/BufferQueue.cpp
@@ -103,6 +103,11 @@ status_t BufferQueue::detachProducerBuffer(int slot) {
     return mProducer->detachBuffer(slot);
 }
 
+status_t BufferQueue::detachNextBuffer(sp<GraphicBuffer>* outBuffer,
+        sp<Fence>* outFence) {
+    return mProducer->detachNextBuffer(outBuffer, outFence);
+}
+
 status_t BufferQueue::attachProducerBuffer(int* slot,
         const sp<GraphicBuffer>& buffer) {
     return mProducer->attachBuffer(slot, buffer);
diff --git a/libs/gui/BufferQueueProducer.cpp b/libs/gui/BufferQueueProducer.cpp
index ea37309..61846dd 100644
--- a/libs/gui/BufferQueueProducer.cpp
+++ b/libs/gui/BufferQueueProducer.cpp
@@ -393,6 +393,50 @@ status_t BufferQueueProducer::detachBuffer(int slot) {
     return NO_ERROR;
 }
 
+status_t BufferQueueProducer::detachNextBuffer(sp<GraphicBuffer>* outBuffer,
+        sp<Fence>* outFence) {
+    ATRACE_CALL();
+
+    if (outBuffer == NULL) {
+        BQ_LOGE("detachNextBuffer: outBuffer must not be NULL");
+        return BAD_VALUE;
+    } else if (outFence == NULL) {
+        BQ_LOGE("detachNextBuffer: outFence must not be NULL");
+        return BAD_VALUE;
+    }
+
+    Mutex::Autolock lock(mCore->mMutex);
+
+    if (mCore->mIsAbandoned) {
+        BQ_LOGE("detachNextBuffer: BufferQueue has been abandoned");
+        return NO_INIT;
+    }
+
+    // Find the oldest valid slot
+    int found = BufferQueueCore::INVALID_BUFFER_SLOT;
+    for (int s = 0; s < BufferQueueDefs::NUM_BUFFER_SLOTS; ++s) {
+        if (mSlots[s].mBufferState == BufferSlot::FREE &&
+                mSlots[s].mGraphicBuffer != NULL) {
+            if (found == BufferQueueCore::INVALID_BUFFER_SLOT ||
+                    mSlots[s].mFrameNumber < mSlots[found].mFrameNumber) {
+                found = s;
+            }
+        }
+    }
+
+    if (found == BufferQueueCore::INVALID_BUFFER_SLOT) {
+        return NO_MEMORY;
+    }
+
+    BQ_LOGV("detachNextBuffer detached slot %d", found);
+
+    *outBuffer = mSlots[found].mGraphicBuffer;
+    *outFence = mSlots[found].mFence;
+    mCore->freeBufferLocked(found);
+
+    return NO_ERROR;
+}
+
 status_t BufferQueueProducer::attachBuffer(int* outSlot,
         const sp<android::GraphicBuffer>& buffer) {
     ATRACE_CALL();
diff --git a/libs/gui/IGraphicBufferProducer.cpp b/libs/gui/IGraphicBufferProducer.cpp
index c0b08c1..aa6acb9 100644
--- a/libs/gui/IGraphicBufferProducer.cpp
+++ b/libs/gui/IGraphicBufferProducer.cpp
@@ -37,6 +37,7 @@ enum {
     SET_BUFFER_COUNT,
     DEQUEUE_BUFFER,
     DETACH_BUFFER,
+    DETACH_NEXT_BUFFER,
     ATTACH_BUFFER,
     QUEUE_BUFFER,
     CANCEL_BUFFER,
@@ -123,6 +124,37 @@ public:
         return result;
     }
 
+    virtual status_t detachNextBuffer(sp<GraphicBuffer>* outBuffer,
+            sp<Fence>* outFence) {
+        if (outBuffer == NULL) {
+            ALOGE("detachNextBuffer: outBuffer must not be NULL");
+            return BAD_VALUE;
+        } else if (outFence == NULL) {
+            ALOGE("detachNextBuffer: outFence must not be NULL");
+            return BAD_VALUE;
+        }
+        Parcel data, reply;
+        data.writeInterfaceToken(IGraphicBufferProducer::getInterfaceDescriptor());
+        status_t result = remote()->transact(DETACH_NEXT_BUFFER, data, &reply);
+        if (result != NO_ERROR) {
+            return result;
+        }
+        result = reply.readInt32();
+        if (result == NO_ERROR) {
+            bool nonNull = reply.readInt32();
+            if (nonNull) {
+                *outBuffer = new GraphicBuffer;
+                reply.read(**outBuffer);
+            }
+            nonNull = reply.readInt32();
+            if (nonNull) {
+                *outFence = new Fence;
+                reply.read(**outFence);
+            }
+        }
+        return result;
+    }
+
     virtual status_t attachBuffer(int* slot, const sp<GraphicBuffer>& buffer) {
         Parcel data, reply;
         data.writeInterfaceToken(IGraphicBufferProducer::getInterfaceDescriptor());
@@ -274,6 +306,24 @@ status_t BnGraphicBufferProducer::onTransact(
             reply->writeInt32(result);
             return NO_ERROR;
         } break;
+        case DETACH_NEXT_BUFFER: {
+            CHECK_INTERFACE(IGraphicBufferProducer, data, reply);
+            sp<GraphicBuffer> buffer;
+            sp<Fence> fence;
+            int32_t result = detachNextBuffer(&buffer, &fence);
+            reply->writeInt32(result);
+            if (result == NO_ERROR) {
+                reply->writeInt32(buffer != NULL);
+                if (buffer != NULL) {
+                    reply->write(*buffer);
+                }
+                reply->writeInt32(fence != NULL);
+                if (fence != NULL) {
+                    reply->write(*fence);
+                }
+            }
+            return NO_ERROR;
+        } break;
         case ATTACH_BUFFER: {
             CHECK_INTERFACE(IGraphicBufferProducer, data, reply);
             sp<GraphicBuffer> buffer = new GraphicBuffer();