Add BufferItemConsumer, a simple BufferQueue consumer.

BufferItemConsumer allows for acquiring BufferQueue's BufferItems,
which contain all the data and metadata the BufferQueue has for a
given graphics buffer.

This consumer is useful when direct access to the native buffer_handles
is needed by the client.

Also includes a minor cleanup of CpuConsumer's use of 'virtual'.

Bug: 6243944
Change-Id: If7dc4192b15ac499555f1eda42a85140f2434795

3 files changed, 98 insertions, 1 deletions

diff --git a/libs/gui/Android.mk b/libs/gui/Android.mk
index 3aa3a50..2bf363f 100644
--- a/libs/gui/Android.mk
+++ b/libs/gui/Android.mk
@@ -23,7 +23,8 @@ LOCAL_SRC_FILES:= \
 	Surface.cpp \
 	SurfaceComposerClient.cpp \
 	DummyConsumer.cpp \
-	CpuConsumer.cpp
+	CpuConsumer.cpp \
+	BufferItemConsumer.cpp
 
 LOCAL_SHARED_LIBRARIES := \
 	libbinder \
diff --git a/libs/gui/BufferItemConsumer.cpp b/libs/gui/BufferItemConsumer.cpp
new file mode 100644
index 0000000..218d929
--- /dev/null
+++ b/libs/gui/BufferItemConsumer.cpp
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "BufferItemConsumer"
+#define ATRACE_TAG ATRACE_TAG_GRAPHICS
+#include <utils/Log.h>
+
+#include <gui/BufferItemConsumer.h>
+
+#define BI_LOGV(x, ...) ALOGV("[%s] "x, mName.string(), ##__VA_ARGS__)
+#define BI_LOGD(x, ...) ALOGD("[%s] "x, mName.string(), ##__VA_ARGS__)
+#define BI_LOGI(x, ...) ALOGI("[%s] "x, mName.string(), ##__VA_ARGS__)
+#define BI_LOGW(x, ...) ALOGW("[%s] "x, mName.string(), ##__VA_ARGS__)
+#define BI_LOGE(x, ...) ALOGE("[%s] "x, mName.string(), ##__VA_ARGS__)
+
+namespace android {
+
+BufferItemConsumer::BufferItemConsumer(uint32_t consumerUsage,
+        int bufferCount, bool synchronousMode) :
+    ConsumerBase(new BufferQueue(true, bufferCount) )
+{
+    mBufferQueue->setConsumerUsageBits(consumerUsage);
+    mBufferQueue->setSynchronousMode(synchronousMode);
+}
+
+BufferItemConsumer::~BufferItemConsumer() {
+}
+
+void BufferItemConsumer::setName(const String8& name) {
+    Mutex::Autolock _l(mMutex);
+    mName = name;
+    mBufferQueue->setConsumerName(name);
+}
+
+status_t BufferItemConsumer::acquireBuffer(BufferItem *item, bool waitForFence) {
+    status_t err;
+
+    if (!item) return BAD_VALUE;
+
+    Mutex::Autolock _l(mMutex);
+
+    err = acquireBufferLocked(item);
+    if (err != OK) {
+        if (err != NO_BUFFER_AVAILABLE) {
+            BI_LOGE("Error acquiring buffer: %s (%d)", strerror(err), err);
+        }
+        return err;
+    }
+
+    if (waitForFence && item->mFence.get()) {
+        err = item->mFence->wait(Fence::TIMEOUT_NEVER);
+        if (err != OK) {
+            BI_LOGE("Failed to wait for fence of acquired buffer: %s (%d)",
+                    strerror(-err), err);
+            return err;
+        }
+    }
+
+    item->mGraphicBuffer = mSlots[item->mBuf].mGraphicBuffer;
+
+    return OK;
+}
+
+status_t BufferItemConsumer::releaseBuffer(const BufferItem &item,
+        const sp<Fence>& releaseFence) {
+    status_t err;
+
+    Mutex::Autolock _l(mMutex);
+
+    err = releaseBufferLocked(item.mBuf, EGL_NO_DISPLAY,
+            EGL_NO_SYNC_KHR, releaseFence);
+    if (err != OK) {
+        BI_LOGE("Failed to release buffer: %s (%d)",
+                strerror(-err), err);
+    }
+    return err;
+}
+
+} // namespace android
diff --git a/libs/gui/CpuConsumer.cpp b/libs/gui/CpuConsumer.cpp
index 90c8ea6..242ac45 100644
--- a/libs/gui/CpuConsumer.cpp
+++ b/libs/gui/CpuConsumer.cpp
@@ -43,6 +43,9 @@ CpuConsumer::CpuConsumer(uint32_t maxLockedBuffers) :
     mBufferQueue->setConsumerUsageBits(GRALLOC_USAGE_SW_READ_OFTEN);
 }
 
+CpuConsumer::~CpuConsumer() {
+}
+
 void CpuConsumer::setName(const String8& name) {
     Mutex::Autolock _l(mMutex);
     mName = name;