1 files changed, 90 insertions, 0 deletions
diff --git a/webrtc/common_video/i420_buffer_pool.cc b/webrtc/common_video/i420_buffer_pool.cc
new file mode 100644
index 0000000000..c746666a16
--- /dev/null
+++ b/webrtc/common_video/i420_buffer_pool.cc
@@ -0,0 +1,90 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/common_video/interface/i420_buffer_pool.h"
+
+#include "webrtc/base/checks.h"
+
+namespace {
+
+// One extra indirection is needed to make |HasOneRef| work.
+class PooledI420Buffer : public webrtc::VideoFrameBuffer {
+ public:
+  explicit PooledI420Buffer(
+      const rtc::scoped_refptr<webrtc::I420Buffer>& buffer)
+      : buffer_(buffer) {}
+
+ private:
+  ~PooledI420Buffer() override {}
+
+  int width() const override { return buffer_->width(); }
+  int height() const override { return buffer_->height(); }
+  const uint8_t* data(webrtc::PlaneType type) const override {
+    return buffer_->data(type);
+  }
+  uint8_t* MutableData(webrtc::PlaneType type) override {
+    // Make the HasOneRef() check here instead of in |buffer_|, because the pool
+    // also has a reference to |buffer_|.
+    RTC_DCHECK(HasOneRef());
+    return const_cast<uint8_t*>(buffer_->data(type));
+  }
+  int stride(webrtc::PlaneType type) const override {
+    return buffer_->stride(type);
+  }
+  void* native_handle() const override { return nullptr; }
+
+  rtc::scoped_refptr<VideoFrameBuffer> NativeToI420Buffer() override {
+    RTC_NOTREACHED();
+    return nullptr;
+  }
+
+  friend class rtc::RefCountedObject<PooledI420Buffer>;
+  rtc::scoped_refptr<webrtc::I420Buffer> buffer_;
+};
+
+}  // namespace
+
+namespace webrtc {
+
+I420BufferPool::I420BufferPool() {
+  Release();
+}
+
+void I420BufferPool::Release() {
+  thread_checker_.DetachFromThread();
+  buffers_.clear();
+}
+
+rtc::scoped_refptr<VideoFrameBuffer> I420BufferPool::CreateBuffer(int width,
+                                                                  int height) {
+  RTC_DCHECK(thread_checker_.CalledOnValidThread());
+  // Release buffers with wrong resolution.
+  for (auto it = buffers_.begin(); it != buffers_.end();) {
+    if ((*it)->width() != width || (*it)->height() != height)
+      it = buffers_.erase(it);
+    else
+      ++it;
+  }
+  // Look for a free buffer.
+  for (const rtc::scoped_refptr<I420Buffer>& buffer : buffers_) {
+    // If the buffer is in use, the ref count will be 2, one from the list we
+    // are looping over and one from a PooledI420Buffer returned from
+    // CreateBuffer that has not been released yet. If the ref count is 1
+    // (HasOneRef), then the list we are looping over holds the only reference
+    // and it's safe to reuse.
+    if (buffer->HasOneRef())
+      return new rtc::RefCountedObject<PooledI420Buffer>(buffer);
+  }
+  // Allocate new buffer.
+  buffers_.push_back(new rtc::RefCountedObject<I420Buffer>(width, height));
+  return new rtc::RefCountedObject<PooledI420Buffer>(buffers_.back());
+}
+
+}  // namespace webrtc