1 files changed, 174 insertions, 0 deletions
diff --git a/media/libstagefright/MediaBuffer.cpp b/media/libstagefright/MediaBuffer.cpp
new file mode 100644
index 0000000..cd78dbd
--- /dev/null
+++ b/media/libstagefright/MediaBuffer.cpp
@@ -0,0 +1,174 @@
+/*
+ * Copyright (C) 2009 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_TAG "MediaBuffer"
+#include <utils/Log.h>
+
+#undef NDEBUG
+#include <assert.h>
+
+#include <errno.h>
+#include <pthread.h>
+#include <stdlib.h>
+
+#include <media/stagefright/MediaBuffer.h>
+#include <media/stagefright/MetaData.h>
+
+namespace android {
+
+// XXX make this truly atomic.
+static int atomic_add(int *value, int delta) {
+    int prev_value = *value;
+    *value += delta;
+
+    return prev_value;
+}
+
+MediaBuffer::MediaBuffer(void *data, size_t size)
+    : mObserver(NULL),
+      mNextBuffer(NULL),
+      mRefCount(0),
+      mData(data),
+      mSize(size),
+      mRangeOffset(0),
+      mRangeLength(size),
+      mOwnsData(false),
+      mMetaData(new MetaData),
+      mOriginal(NULL) {
+}
+
+MediaBuffer::MediaBuffer(size_t size)
+    : mObserver(NULL),
+      mNextBuffer(NULL),
+      mRefCount(0),
+      mData(malloc(size)),
+      mSize(size),
+      mRangeOffset(0),
+      mRangeLength(size),
+      mOwnsData(true),
+      mMetaData(new MetaData),
+      mOriginal(NULL) {
+}
+
+void MediaBuffer::release() {
+    if (mObserver == NULL) {
+        assert(mRefCount == 0);
+        delete this;
+        return;
+    }
+
+    int prevCount = atomic_add(&mRefCount, -1);
+    if (prevCount == 1) {
+        if (mObserver == NULL) {
+            delete this;
+            return;
+        }
+
+        mObserver->signalBufferReturned(this);
+    }
+    assert(prevCount > 0);
+}
+
+void MediaBuffer::claim() {
+    assert(mObserver != NULL);
+    assert(mRefCount == 1);
+
+    mRefCount = 0;
+}
+
+void MediaBuffer::add_ref() {
+    atomic_add(&mRefCount, 1);
+}
+
+void *MediaBuffer::data() const {
+    return mData;
+}
+
+size_t MediaBuffer::size() const {
+    return mSize;
+}
+
+size_t MediaBuffer::range_offset() const {
+    return mRangeOffset;
+}
+
+size_t MediaBuffer::range_length() const {
+    return mRangeLength;
+}
+
+void MediaBuffer::set_range(size_t offset, size_t length) {
+    if (offset < 0 || offset + length > mSize) {
+        LOGE("offset = %d, length = %d, mSize = %d", offset, length, mSize);
+    }
+    assert(offset >= 0 && offset + length <= mSize);
+
+    mRangeOffset = offset;
+    mRangeLength = length;
+}
+
+sp<MetaData> MediaBuffer::meta_data() {
+    return mMetaData;
+}
+
+void MediaBuffer::reset() {
+    mMetaData->clear();
+    set_range(0, mSize);
+}
+
+MediaBuffer::~MediaBuffer() {
+    assert(mObserver == NULL);
+
+    if (mOwnsData && mData != NULL) {
+        free(mData);
+        mData = NULL;
+    }
+
+    if (mOriginal != NULL) {
+        mOriginal->release();
+        mOriginal = NULL;
+    }
+}
+
+void MediaBuffer::setObserver(MediaBufferObserver *observer) {
+    assert(observer == NULL || mObserver == NULL);
+    mObserver = observer;
+}
+
+void MediaBuffer::setNextBuffer(MediaBuffer *buffer) {
+    mNextBuffer = buffer;
+}
+
+MediaBuffer *MediaBuffer::nextBuffer() {
+    return mNextBuffer;
+}
+
+int MediaBuffer::refcount() const {
+    return mRefCount;
+}
+
+MediaBuffer *MediaBuffer::clone() {
+    MediaBuffer *buffer = new MediaBuffer(mData, mSize);
+    buffer->set_range(mRangeOffset, mRangeLength);
+    buffer->mMetaData = new MetaData(*mMetaData.get());
+
+    add_ref();
+    buffer->mOriginal = this;
+
+    return buffer;
+}
+
+}  // namespace android
+