Basic HTTP pipelining support

net/http/http_pipelined_host_pool.h

+// Copyright (c) 2011 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.
+
+#ifndef NET_HTTP_HTTP_PIPELINED_HOST_POOL_H_
+#define NET_HTTP_HTTP_PIPELINED_HOST_POOL_H_
+#pragma once
+
+#include <map>
+
+#include "base/basictypes.h"
+#include "net/http/http_pipelined_host.h"
+
+namespace net {
+
+class HostPortPair;
+class HttpPipelinedStream;
+class HttpStreamFactoryImpl;
+
+// Manages all of the pipelining state for specific host with active pipelined
+// HTTP requests. Manages connection jobs, constructs pipelined streams, and
+// assigns requests to the least loaded pipelined connection.
+class HttpPipelinedHostPool : public HttpPipelinedHost::Delegate {
+ public:
+  explicit HttpPipelinedHostPool(HttpStreamFactoryImpl* factory);
+  ~HttpPipelinedHostPool();
+
+  // Constructs a new pipeline on |connection| and returns a new
+  // HttpPipelinedStream that uses it.
+  HttpPipelinedStream* CreateStreamOnNewPipeline(
+      const HostPortPair& origin,
+      ClientSocketHandle* connection,
+      const SSLConfig& used_ssl_config,
+      const ProxyInfo& used_proxy_info,
+      const BoundNetLog& net_log,
+      bool was_npn_negotiated);
+
+  // Tries to find an existing pipeline with capacity for a new request. If
+  // successful, returns a new stream on that pipeline. Otherwise, returns NULL.
+  HttpPipelinedStream* CreateStreamOnExistingPipeline(
+      const HostPortPair& origin);
+
+  // Returns true if a pipelined connection already exists for this origin and
+  // can accept new requests.
+  bool IsExistingPipelineAvailableForOrigin(const HostPortPair& origin);
+
+  // Callbacks for HttpPipelinedHost.
+  virtual void OnHostIdle(HttpPipelinedHost* host) OVERRIDE;
+
+  virtual void OnHostHasAdditionalCapacity(HttpPipelinedHost* host) OVERRIDE;
+
+ private:
+  typedef std::map<const HostPortPair, HttpPipelinedHost*> HostMap;
+
+  HttpPipelinedHost* GetPipelinedHost(const HostPortPair& origin,
+                                      bool create_if_not_found);
+
+  HttpStreamFactoryImpl* factory_;
+  HostMap host_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(HttpPipelinedHostPool);
+};
+
+}  // namespace net
+
+#endif  // NET_HTTP_HTTP_PIPELINED_HOST_POOL_H_