Basic HTTP pipelining support

net/http/http_stream_factory_impl_job.cc

Index: net/http/http_stream_factory_impl_job.cc
diff --git a/net/http/http_stream_factory_impl_job.cc b/net/http/http_stream_factory_impl_job.cc
index dcbf1149f24ba7dfa93f43a365c1048c8d851fc6..0046919b954928cc34fdfdf68dd83097b9a9c203 100644
--- a/net/http/http_stream_factory_impl_job.cc
+++ b/net/http/http_stream_factory_impl_job.cc
@@ -16,9 +16,14 @@
 #include "net/base/ssl_cert_request_info.h"
 #include "net/http/http_basic_stream.h"
 #include "net/http/http_network_session.h"
+#include "net/http/http_pipelined_connection.h"
+#include "net/http/http_pipelined_host.h"
+#include "net/http/http_pipelined_host_pool.h"
+#include "net/http/http_pipelined_stream.h"
 #include "net/http/http_proxy_client_socket.h"
 #include "net/http/http_proxy_client_socket_pool.h"
 #include "net/http/http_request_info.h"
+#include "net/http/http_stream_factory.h"
 #include "net/http/http_stream_factory_impl_request.h"
 #include "net/socket/client_socket_handle.h"
 #include "net/socket/client_socket_pool.h"
@@ -85,6 +90,7 @@ HttpStreamFactoryImpl::Job::Job(HttpStreamFactoryImpl* stream_factory,
       was_npn_negotiated_(false),
       num_streams_(0),
       spdy_session_direct_(false),
+      existing_available_pipeline_(NULL),
       ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)) {
   DCHECK(stream_factory);
   DCHECK(session);
@@ -580,6 +586,18 @@ int HttpStreamFactoryImpl::Job::DoInitConnection() {
   } else if (request_ && (using_ssl_ || ShouldForceSpdyWithoutSSL())) {
     // Update the spdy session key for the request that launched this job.
     request_->SetSpdySessionKey(spdy_session_key);
+  } else if (IsRequestEligibleForPipelining()) {
+    HttpPipelinedHost* host = session_->http_pipelined_host_pool()->
+        GetPipelinedHostIfExists(origin_);
+    if (host) {
+      HttpPipelinedConnection* connection = host->FindAvailablePipeline();
+      if (connection) {
+        next_state_ = STATE_CREATE_STREAM;
+        existing_available_pipeline_ = connection;
+        return OK;
+      }
+    }
+    request_->SetHttpPipeliningKey(origin_);
   }
 
   // OK, there's no available SPDY session. Let |dependent_job_| resume if it's
@@ -757,9 +775,13 @@ int HttpStreamFactoryImpl::Job::DoWaitingUserAction(int result) {
 }
 
 int HttpStreamFactoryImpl::Job::DoCreateStream() {
-  if (!connection_->socket() && !existing_spdy_session_)
+  if (!connection_->socket() && !existing_spdy_session_ &&
+      !existing_available_pipeline_)
     HACKCrashHereToDebug80095();
 
+  DCHECK(connection_->socket() || existing_spdy_session_ ||
+         existing_available_pipeline_);
+
   next_state_ = STATE_CREATE_STREAM_COMPLETE;
 
   // We only set the socket motivation if we're the first to use
@@ -773,8 +795,22 @@ int HttpStreamFactoryImpl::Job::DoCreateStream() {
   if (!using_spdy_) {
     bool using_proxy = (proxy_info_.is_http() || proxy_info_.is_https()) &&
         request_info_.url.SchemeIs("http");
-    stream_.reset(new HttpBasicStream(connection_.release(), NULL,
-                                      using_proxy));
+    // TODO(simonjam): Support proxies.
+    if (existing_available_pipeline_) {
+      stream_.reset(existing_available_pipeline_->CreateNewStream());
+    } else if (!using_proxy && IsRequestEligibleForPipelining()) {
+      HttpPipelinedConnection* pipeline = session_->http_pipelined_host_pool()->
+          GetOrCreatePipelinedHost(origin_)->CreateNewPipeline(
+              connection_.release(),
+              ssl_config_,
+              proxy_info_,
+              net_log_,
+              was_npn_negotiated_);
+      stream_.reset(pipeline->CreateNewStream());
+    } else {
+      stream_.reset(new HttpBasicStream(connection_.release(), NULL,
+                                        using_proxy));
+    }
     return OK;
   }
 
@@ -1079,6 +1115,19 @@ bool HttpStreamFactoryImpl::Job::IsOrphaned() const {
   return !IsPreconnecting() && !request_;
 }
 
+bool HttpStreamFactoryImpl::Job::IsRequestEligibleForPipelining() const {
+  if (!HttpStreamFactory::http_pipelining_enabled()) {
+    return false;
+  }
+  if (IsPreconnecting() || !request_) {
+    return false;
+  }
+  if (using_ssl_) {
+    return false;
+  }
+  return request_info_.method == "GET" || request_info_.method == "HEAD";
+}
+
 #if defined(OS_WIN)
 #pragma warning (disable: 4748)
 #pragma optimize( "", off )