Basic HTTP pipelining support

net/http/http_stream_factory.h

Index: net/http/http_stream_factory.h
diff --git a/net/http/http_stream_factory.h b/net/http/http_stream_factory.h
index 66c0a23d580255b82b4d26b139cd46f3403a97c1..a572ae3f8d8551bc9ef3e1259c7ac73b1bfbf538 100644
--- a/net/http/http_stream_factory.h
+++ b/net/http/http_stream_factory.h
@@ -24,6 +24,7 @@ class HostPortPair;
 class HttpAlternateProtocols;
 class HttpAuthController;
 class HttpNetworkSession;
+class HttpPipelinedHost;
 class HttpResponseInfo;
 class HttpStream;
 class ProxyInfo;
@@ -174,6 +175,11 @@ class NET_EXPORT HttpStreamFactory {
   virtual void AddTLSIntolerantServer(const HostPortPair& server) = 0;
   virtual bool IsTLSIntolerantServer(const HostPortPair& server) const = 0;
 
+  // Called when a HttpPipelinedHost has new capacity. Attempts to allocate any
+  // pending pipeline-capable requests to pipelines.
+  virtual void OnHttpPipelinedHostHasAdditionalCapacity(

[willchan no longer on Chromium, 2011/09/29 23:36:02]

I consider pipelining an implementation detail. Not every HttpStreamFactory
implementation needs to support it. Therefore, I think you should move this
virtual to HttpStreamFactoryImpl.

[James Simonsen, 2011/10/12 01:36:58]

I tried this, but I didn't like it.

The pool gets access to the factory through the session. Changing this means the
session needs to return a FactoryImpl. That seems wrong.

An alternative would be to have the FactoryImpl own the pool, but that breaks
the symmetry with SPDY and I think the session is the right place for the pool.

My vote is to punt on this until we really do have different factories. Then we
can work it out.

[James Simonsen, 2011/10/13 19:29:57]

Done.

+      const HostPortPair& origin) = 0;
+
   // Static settings
   static GURL ApplyHostMappingRules(const GURL& url, HostPortPair* endpoint);
 
@@ -228,6 +234,11 @@ class NET_EXPORT HttpStreamFactory {
 
   static void SetHostMappingRules(const std::string& rules);
 
+  static void set_http_pipelining_enabled(bool value) {
+    http_pipelining_enabled_ = value;
+  }
+  static bool http_pipelining_enabled() { return http_pipelining_enabled_; }
+
  protected:
   HttpStreamFactory();
 
@@ -242,6 +253,7 @@ class NET_EXPORT HttpStreamFactory {
   static bool force_spdy_always_;
   static std::list<HostPortPair>* forced_spdy_exclusions_;
   static bool ignore_certificate_errors_;
+  static bool http_pipelining_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpStreamFactory);
 };