[ON HOLD] Implement pull-based design for content decoding

net/filter/block_buffer.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/filter/block_buffer.h"
+
+namespace {
+
+const size_t kBufferSize = 32 * 1024;
+
+}  // namespace
+
+namespace net {
+
+BlockBuffer::BlockBuffer()
+    : buffer_(new IOBuffer(kBufferSize)),
+      bytes_(buffer_->data()),
+      bytes_left_(0) {}
+BlockBuffer::~BlockBuffer() {}
+
+bool BlockBuffer::HasMoreBytes() const {
+  return bytes_left_ > 0;
+}
+
+void BlockBuffer::WasRefilled(size_t filled_bytes) {
+  DCHECK(bytes_left_ == 0);
+  bytes_ = buffer_->data();
+  bytes_left_ = filled_bytes;
+}
+
+void BlockBuffer::WasDrained(size_t drained_bytes) {
+  DCHECK(drained_bytes <= bytes_left_);
+  bytes_left_ -= drained_bytes;
+  bytes_ += drained_bytes;
+}
+
+size_t BlockBuffer::size() const {
+  return kBufferSize;
+}
+
+}  // namespace net