[Cronet] Make delaying sending request headers explicit in bidirectional stream

net/quic/bidirectional_stream_quic_impl.cc

 // Copyright 2016 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/quic/bidirectional_stream_quic_impl.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/timer/timer.h"
@@ skipping 14 matching lines @@
       delegate_(nullptr),
       response_status_(OK),
       negotiated_protocol_(kProtoUnknown),
       read_buffer_len_(0),
       headers_bytes_received_(0),
       headers_bytes_sent_(0),
       closed_stream_received_bytes_(0),
       closed_stream_sent_bytes_(0),
       has_sent_headers_(false),
       has_received_headers_(false),
-      disable_auto_flush_(false),
+      send_request_headers_automatically_(true),
       weak_factory_(this) {
   DCHECK(session_);
   session_->AddObserver(this);
 }
 
 BidirectionalStreamQuicImpl::~BidirectionalStreamQuicImpl() {
   Cancel();
   if (session_)
     session_->RemoveObserver(this);
 }
 
 void BidirectionalStreamQuicImpl::Start(
     const BidirectionalStreamRequestInfo* request_info,
     const BoundNetLog& net_log,
-    bool disable_auto_flush,
+    bool send_request_headers_automatically,
     BidirectionalStreamImpl::Delegate* delegate,
     std::unique_ptr<base::Timer> /* timer */) {
   DCHECK(!stream_);
 
-  disable_auto_flush_ = disable_auto_flush;
+  send_request_headers_automatically_ = send_request_headers_automatically;
   if (!session_) {
     NotifyError(was_handshake_confirmed_ ? ERR_QUIC_PROTOCOL_ERROR
                                          : ERR_QUIC_HANDSHAKE_FAILED);
     return;
   }
 
   delegate_ = delegate;
   request_info_ = request_info;
 
   int rv = stream_request_.StartRequest(
       session_, &stream_,
       base::Bind(&BidirectionalStreamQuicImpl::OnStreamReady,
                  weak_factory_.GetWeakPtr()));
   if (rv == OK) {
     OnStreamReady(rv);
   } else if (!was_handshake_confirmed_) {
     NotifyError(ERR_QUIC_HANDSHAKE_FAILED);
   }
 }
 
+void BidirectionalStreamQuicImpl::SendRequestHeaders() {
+  DCHECK(!has_sent_headers_);
+  DCHECK(stream_);
+
+  SpdyHeaderBlock headers;
+  HttpRequestInfo http_request_info;
+  http_request_info.url = request_info_->url;
+  http_request_info.method = request_info_->method;
+  http_request_info.extra_headers = request_info_->extra_headers;
+
+  CreateSpdyHeadersFromHttpRequest(http_request_info,
+                                   http_request_info.extra_headers, HTTP2, true,
+                                   &headers);
+  size_t headers_bytes_sent = stream_->WriteHeaders(
+      headers, request_info_->end_stream_on_headers, nullptr);
+  headers_bytes_sent_ += headers_bytes_sent;
+  has_sent_headers_ = true;
+}
+
 int BidirectionalStreamQuicImpl::ReadData(IOBuffer* buffer, int buffer_len) {
   DCHECK(buffer);
   DCHECK(buffer_len);
 
   if (!stream_) {
     // If the stream is already closed, there is no body to read.
     return response_status_;
   }
   int rv = stream_->Read(buffer, buffer_len);
   if (rv != ERR_IO_PENDING) {
@@ skipping 10 matching lines @@
   read_buffer_len_ = buffer_len;
   return ERR_IO_PENDING;
 }
 
 void BidirectionalStreamQuicImpl::SendData(const scoped_refptr<IOBuffer>& data,
                                            int length,
                                            bool end_stream) {
   DCHECK(stream_);
   DCHECK(length > 0 || (length == 0 && end_stream));
 
+  std::unique_ptr<QuicConnection::ScopedPacketBundler> bundler;
+  if (!has_sent_headers_) {
+    DCHECK(!send_request_headers_automatically_);
+    // Creates a bundler only if there are headers to be sent along with the
+    // single data buffer.
+    bundler.reset(new QuicConnection::ScopedPacketBundler(
+        session_->connection(), QuicConnection::SEND_ACK_IF_PENDING));
+    SendRequestHeaders();
+  }
+
   base::StringPiece string_data(data->data(), length);
   int rv = stream_->WriteStreamData(
       string_data, end_stream,
       base::Bind(&BidirectionalStreamQuicImpl::OnSendDataComplete,
                  weak_factory_.GetWeakPtr()));
   DCHECK(rv == OK || rv == ERR_IO_PENDING);
   if (rv == OK) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&BidirectionalStreamQuicImpl::OnSendDataComplete,
                               weak_factory_.GetWeakPtr(), OK));
   }
 }
 
 void BidirectionalStreamQuicImpl::SendvData(
     const std::vector<scoped_refptr<IOBuffer>>& buffers,
     const std::vector<int>& lengths,
     bool end_stream) {
   DCHECK(stream_);
   DCHECK_EQ(buffers.size(), lengths.size());
 
   QuicConnection::ScopedPacketBundler bundler(
       session_->connection(), QuicConnection::SEND_ACK_IF_PENDING);
   if (!has_sent_headers_) {
+    DCHECK(!send_request_headers_automatically_);
     SendRequestHeaders();
   }
 
   int rv = stream_->WritevStreamData(
       buffers, lengths, end_stream,
       base::Bind(&BidirectionalStreamQuicImpl::OnSendDataComplete,
                  weak_factory_.GetWeakPtr()));
 
   DCHECK(rv == OK || rv == ERR_IO_PENDING);
   if (rv == OK) {
@@ skipping 92 matching lines @@
   DCHECK_NE(OK, error);
   session_.reset();
   NotifyError(error);
 }
 
 void BidirectionalStreamQuicImpl::OnStreamReady(int rv) {
   DCHECK_NE(ERR_IO_PENDING, rv);
   DCHECK(rv == OK || !stream_);
   if (rv == OK) {
     stream_->SetDelegate(this);
-    if (!disable_auto_flush_) {
+    if (send_request_headers_automatically_) {
       SendRequestHeaders();
     }
-    delegate_->OnStreamReady();
+    delegate_->OnStreamReady(has_sent_headers_);
   } else {
     NotifyError(rv);
   }
 }
 
 void BidirectionalStreamQuicImpl::OnSendDataComplete(int rv) {
   DCHECK(rv == OK || !stream_);
   if (rv == OK) {
     delegate_->OnDataSent();
   } else {
     NotifyError(rv);
   }
 }
 
-void BidirectionalStreamQuicImpl::SendRequestHeaders() {
-  DCHECK(!has_sent_headers_);
-  DCHECK(stream_);
-
-  SpdyHeaderBlock headers;
-  HttpRequestInfo http_request_info;
-  http_request_info.url = request_info_->url;
-  http_request_info.method = request_info_->method;
-  http_request_info.extra_headers = request_info_->extra_headers;
-
-  CreateSpdyHeadersFromHttpRequest(http_request_info,
-                                   http_request_info.extra_headers, HTTP2, true,
-                                   &headers);
-  size_t frame_len = stream_->WriteHeaders(
-      headers, request_info_->end_stream_on_headers, nullptr);
-  headers_bytes_sent_ += frame_len;
-  has_sent_headers_ = true;
-}
-
 void BidirectionalStreamQuicImpl::NotifyError(int error) {
   DCHECK_NE(OK, error);
   DCHECK_NE(ERR_IO_PENDING, error);
 
   response_status_ = error;
   ResetStream();
   delegate_->OnFailed(error);
 }
 
 void BidirectionalStreamQuicImpl::ResetStream() {
   if (!stream_)
     return;
   closed_stream_received_bytes_ = stream_->stream_bytes_read();
   closed_stream_sent_bytes_ = stream_->stream_bytes_written();
   stream_->SetDelegate(nullptr);
   stream_ = nullptr;
 }
 
 }  // namespace net