Refactor ResourceHandler API.

content/browser/loader/stream_writer.cc

 // Copyright 2014 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 "content/browser/loader/stream_writer.h"
 
 #include "base/guid.h"
 #include "content/browser/loader/resource_controller.h"
 #include "content/browser/streams/stream.h"
 #include "content/browser/streams/stream_registry.h"
 #include "net/base/io_buffer.h"
 #include "url/gurl.h"
 #include "url/url_constants.h"
 
 namespace content {
 
-StreamWriter::StreamWriter() : controller_(nullptr), immediate_mode_(false) {
-}
+StreamWriter::StreamWriter() : immediate_mode_(false) {}
 
 StreamWriter::~StreamWriter() {
   if (stream_.get())
     Finalize(0);
 }
 
 void StreamWriter::InitializeStream(StreamRegistry* registry,
-                                    const GURL& origin) {
+                                    const GURL& origin,
+                                    const base::Closure& cancel_callback) {
+  cancel_callback_ = cancel_callback;
   DCHECK(!stream_.get());
 
   // TODO(tyoshino): Find a way to share this with the blob URL creation in
   // WebKit.
   GURL url(std::string(url::kBlobScheme) + ":" + origin.spec() +
            base::GenerateGUID());
   stream_ = new Stream(registry, this, url);
 }
 
 void StreamWriter::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                               int* buf_size,
                               int min_size) {
   static const int kReadBufSize = 32768;
 
   DCHECK(buf);
   DCHECK(buf_size);
   DCHECK_LE(min_size, kReadBufSize);
   if (!read_buffer_.get())
     read_buffer_ = new net::IOBuffer(kReadBufSize);
   *buf = read_buffer_.get();
   *buf_size = kReadBufSize;
 }
 
-void StreamWriter::OnReadCompleted(int bytes_read, bool* defer) {
-  if (!bytes_read)
+void StreamWriter::OnReadCompleted(
+    int bytes_read,
+    const base::Closure& need_more_data_callback) {
+  DCHECK(!need_more_data_callback_);
+  if (!bytes_read) {
+    need_more_data_callback.Run();
     return;
+  }
 
   // We have more data to read.
   DCHECK(read_buffer_.get());
 
   // Release the ownership of the buffer, and store a reference
   // to it. A new one will be allocated in OnWillRead().
   scoped_refptr<net::IOBuffer> buffer;
   read_buffer_.swap(buffer);
   stream_->AddData(buffer, bytes_read);
 
   if (immediate_mode_)
     stream_->Flush();
 
-  if (!stream_->can_add_data())
-    *defer = true;
+  if (!stream_->can_add_data()) {
+    need_more_data_callback_ = need_more_data_callback;
+    return;
+  }
+  need_more_data_callback.Run();
 }
 
 void StreamWriter::Finalize(int status) {
   DCHECK(stream_.get());
   stream_->Finalize(status);
   stream_->RemoveWriteObserver(this);
   stream_ = nullptr;
 }
 
 void StreamWriter::OnSpaceAvailable(Stream* stream) {
-  controller_->Resume();
+  need_more_data_callback_.Run();
 }
 
 void StreamWriter::OnClose(Stream* stream) {
-  controller_->Cancel();
+  cancel_callback_.Run();
 }
 
 }  // namespace content