net: Move write flush responsiblity from URLFetcherResponseWriter to URLFetcherCore

URLFetcherCore is now responsible to write all data stored in |buffer_|.

BUG=126753
TEST=net_unittests

Review URL: https://chromiumcodereview.appspot.com/15711003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@202003 0039d316-1c4b-4281-b951-d872f2087c98

net/url_request/url_fetcher_core.cc

@@ -431,9 +431,7 @@ void URLFetcherCore::OnReadCompleted(URLRequest* request,
     InformDelegateDownloadProgress();
     InformDelegateDownloadDataIfNecessary(bytes_read);
 
-    const int result = response_writer_->Write(
-        buffer_, bytes_read,
-        base::Bind(&URLFetcherCore::DidWriteBuffer, this));
+    const int result = WriteBuffer(new DrainableIOBuffer(buffer_, bytes_read));
     if (result < 0) {
       // Write failed or waiting for write completion.
       if (result == ERR_IO_PENDING)
@@ -822,14 +820,35 @@ void URLFetcherCore::CompleteAddingUploadDataChunk(
                                 is_last_chunk);
 }
 
-void URLFetcherCore::DidWriteBuffer(int result) {
-  if (result < 0) {
+int URLFetcherCore::WriteBuffer(scoped_refptr<DrainableIOBuffer> data) {
+  while (data->BytesRemaining() > 0) {
+    const int result = response_writer_->Write(
+        data, data->BytesRemaining(),
+        base::Bind(&URLFetcherCore::DidWriteBuffer, this, data));
+    if (result < 0)
+      return result;
+    data->DidConsume(result);
+  }
+  return OK;
+}
+
+void URLFetcherCore::DidWriteBuffer(scoped_refptr<DrainableIOBuffer> data,
+                                    int result) {
+  if (result >= 0) {  // Continue writing.
+    data->DidConsume(result);
+    result = WriteBuffer(data);
+    if (result == ERR_IO_PENDING)
+      return;
+  }
+
+  if (result < 0) {  // Handle errors.
     delegate_task_runner_->PostTask(
         FROM_HERE,
         base::Bind(&URLFetcherCore::InformDelegateFetchIsComplete, this));
     return;
   }
   // Finished writing buffer_. Read some more.
+  DCHECK_EQ(0, data->BytesRemaining());
   ReadResponse();
 }
 

net/url_request/url_fetcher_core.h

@@ -28,6 +28,7 @@ class SingleThreadTaskRunner;
 }  // namespace base
 
 namespace net {
+class DrainableIOBuffer;
 class HttpResponseHeaders;
 class IOBuffer;
 class URLFetcherDelegate;
@@ -193,8 +194,13 @@ class URLFetcherCore
   void CompleteAddingUploadDataChunk(const std::string& data,
                                      bool is_last_chunk);
 
-  // Handles the result of WriteBuffer.
-  void DidWriteBuffer(int result);
+  // Writes all bytes stored in |data| with |response_writer_|.
+  // Returns OK if all bytes in |data| get written synchronously. Otherwise,
+  // returns ERR_IO_PENDING or a network error code.
+  int WriteBuffer(scoped_refptr<DrainableIOBuffer> data);
+
+  // Used to implement WriteBuffer().
+  void DidWriteBuffer(scoped_refptr<DrainableIOBuffer> data, int result);
 
   // Read response bytes from the request.
   void ReadResponse();

net/url_request/url_fetcher_response_writer.cc

@@ -91,8 +91,15 @@ int URLFetcherFileWriter::Write(IOBuffer* buffer,
   DCHECK(file_stream_);
   DCHECK(owns_file_);
 
-  ContinueWrite(new DrainableIOBuffer(buffer, num_bytes), callback, OK);
-  return ERR_IO_PENDING;
+  int result = file_stream_->Write(buffer, num_bytes,
+                                   base::Bind(&URLFetcherFileWriter::DidWrite,
+                                              weak_factory_.GetWeakPtr(),
+                                              callback));
+  if (result < 0 && result != ERR_IO_PENDING) {
+    error_code_ = result;
+    CloseAndDeleteFile();
+  }
+  return result;
 }
 
 int URLFetcherFileWriter::Finish(const CompletionCallback& callback) {
@@ -100,33 +107,13 @@ int URLFetcherFileWriter::Finish(const CompletionCallback& callback) {
   return OK;
 }
 
-void URLFetcherFileWriter::ContinueWrite(
-    scoped_refptr<DrainableIOBuffer> buffer,
-    const CompletionCallback& callback,
-    int result) {
-  // |file_stream_| should be alive when write is in progress.
-  DCHECK(file_stream_);
-
+void URLFetcherFileWriter::DidWrite(const CompletionCallback& callback,
+                                    int result) {
   if (result < 0) {
     error_code_ = result;
     CloseAndDeleteFile();
-    callback.Run(result);
-    return;
-  }
-
-  total_bytes_written_ += result;
-  buffer->DidConsume(result);
-
-  if (buffer->BytesRemaining() > 0) {
-    file_stream_->Write(buffer, buffer->BytesRemaining(),
-                        base::Bind(&URLFetcherFileWriter::ContinueWrite,
-                                   weak_factory_.GetWeakPtr(),
-                                   buffer,
-                                   callback));
-  } else {
-    // Finished writing buffer to the file.
-    callback.Run(buffer->size());
   }
+  callback.Run(result);
 }
 
 void URLFetcherFileWriter::DisownFile() {

net/url_request/url_fetcher_response_writer.h

@@ -84,11 +84,8 @@ class URLFetcherFileWriter : public URLFetcherResponseWriter {
                     const CompletionCallback& callback) OVERRIDE;
   virtual int Finish(const CompletionCallback& callback) OVERRIDE;
 
-  // Called when a write has been done.  Continues writing if there are more
-  // bytes to write.  Otherwise, runs |callback|.
-  void ContinueWrite(scoped_refptr<DrainableIOBuffer> buffer,
-                     const CompletionCallback& callback,
-                     int result);
+  // Called when a write has been done.
+  void DidWrite(const CompletionCallback& callback, int result);
 
   // Drops ownership of the file at |file_path_|.
   // This class will not delete it or write to it again.