net/socket/transport_client_socket_pool.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef NET_SOCKET_TRANSPORT_CLIENT_SOCKET_POOL_H_
   6 #define NET_SOCKET_TRANSPORT_CLIENT_SOCKET_POOL_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/time/time.h"
  14 #include "base/timer/timer.h"
  15 #include "net/base/host_port_pair.h"
  16 #include "net/dns/host_resolver.h"
  17 #include "net/dns/single_request_host_resolver.h"
  18 #include "net/socket/client_socket_pool.h"
  19 #include "net/socket/client_socket_pool_base.h"
  20 #include "net/socket/client_socket_pool_histograms.h"
  21
  22 namespace net {
  23
  24 class ClientSocketFactory;
  25
  26 typedef base::Callback<int(const AddressList&, const BoundNetLog& net_log)>
  27 OnHostResolutionCallback;
  28
  29 class NET_EXPORT_PRIVATE TransportSocketParams
  30     : public base::RefCounted<TransportSocketParams> {
  31  public:
  32   // |host_resolution_callback| will be invoked after the the hostname is
  33   // resolved.  If |host_resolution_callback| does not return OK, then the
  34   // connection will be aborted with that value.
  35   TransportSocketParams(
  36       const HostPortPair& host_port_pair,
  37       bool disable_resolver_cache,
  38       bool ignore_limits,
  39       const OnHostResolutionCallback& host_resolution_callback);
  40
  41   const HostResolver::RequestInfo& destination() const { return destination_; }
  42   bool ignore_limits() const { return ignore_limits_; }
  43   const OnHostResolutionCallback& host_resolution_callback() const {
  44     return host_resolution_callback_;
  45   }
  46
  47  private:
  48   friend class base::RefCounted<TransportSocketParams>;
  49   ~TransportSocketParams();
  50
  51   HostResolver::RequestInfo destination_;
  52   bool ignore_limits_;
  53   const OnHostResolutionCallback host_resolution_callback_;
  54
  55   DISALLOW_COPY_AND_ASSIGN(TransportSocketParams);
  56 };
  57
  58 // TransportConnectJob handles the host resolution necessary for socket creation
  59 // and the transport (likely TCP) connect. TransportConnectJob also has fallback
  60 // logic for IPv6 connect() timeouts (which may happen due to networks / routers
  61 // with broken IPv6 support). Those timeouts take 20s, so rather than make the
  62 // user wait 20s for the timeout to fire, we use a fallback timer
  63 // (kIPv6FallbackTimerInMs) and start a connect() to a IPv4 address if the timer
  64 // fires. Then we race the IPv4 connect() against the IPv6 connect() (which has
  65 // a headstart) and return the one that completes first to the socket pool.
  66 class NET_EXPORT_PRIVATE TransportConnectJob : public ConnectJob {
  67  public:
  68   TransportConnectJob(const std::string& group_name,
  69                       RequestPriority priority,
  70                       const scoped_refptr<TransportSocketParams>& params,
  71                       base::TimeDelta timeout_duration,
  72                       ClientSocketFactory* client_socket_factory,
  73                       HostResolver* host_resolver,
  74                       Delegate* delegate,
  75                       NetLog* net_log);
  76   virtual ~TransportConnectJob();
  77
  78   // ConnectJob methods.
  79   virtual LoadState GetLoadState() const OVERRIDE;
  80
  81   // Rolls |addrlist| forward until the first IPv4 address, if any.
  82   // WARNING: this method should only be used to implement the prefer-IPv4 hack.
  83   static void MakeAddressListStartWithIPv4(AddressList* addrlist);
  84
  85   static const int kIPv6FallbackTimerInMs;
  86
  87  private:
  88   enum State {
  89     STATE_RESOLVE_HOST,
  90     STATE_RESOLVE_HOST_COMPLETE,
  91     STATE_TRANSPORT_CONNECT,
  92     STATE_TRANSPORT_CONNECT_COMPLETE,
  93     STATE_NONE,
  94   };
  95
  96   void OnIOComplete(int result);
  97
  98   // Runs the state transition loop.
  99   int DoLoop(int result);
 100
 101   int DoResolveHost();
 102   int DoResolveHostComplete(int result);
 103   int DoTransportConnect();
 104   int DoTransportConnectComplete(int result);
 105
 106   // Not part of the state machine.
 107   void DoIPv6FallbackTransportConnect();
 108   void DoIPv6FallbackTransportConnectComplete(int result);
 109
 110   // Begins the host resolution and the TCP connect.  Returns OK on success
 111   // and ERR_IO_PENDING if it cannot immediately service the request.
 112   // Otherwise, it returns a net error code.
 113   virtual int ConnectInternal() OVERRIDE;
 114
 115   scoped_refptr<TransportSocketParams> params_;
 116   ClientSocketFactory* const client_socket_factory_;
 117   SingleRequestHostResolver resolver_;
 118   AddressList addresses_;
 119   State next_state_;
 120
 121   scoped_ptr<StreamSocket> transport_socket_;
 122
 123   scoped_ptr<StreamSocket> fallback_transport_socket_;
 124   scoped_ptr<AddressList> fallback_addresses_;
 125   base::TimeTicks fallback_connect_start_time_;
 126   base::OneShotTimer<TransportConnectJob> fallback_timer_;
 127
 128   // If the interval between this connect and previous connect is less than
 129   // 20ms, then |less_than_20ms_since_connect_| is set to true.
 130   bool less_than_20ms_since_connect_;
 131
 132   DISALLOW_COPY_AND_ASSIGN(TransportConnectJob);
 133 };
 134
 135 class NET_EXPORT_PRIVATE TransportClientSocketPool : public ClientSocketPool {
 136  public:
 137   typedef TransportSocketParams SocketParams;
 138
 139   TransportClientSocketPool(
 140       int max_sockets,
 141       int max_sockets_per_group,
 142       ClientSocketPoolHistograms* histograms,
 143       HostResolver* host_resolver,
 144       ClientSocketFactory* client_socket_factory,
 145       NetLog* net_log);
 146
 147   virtual ~TransportClientSocketPool();
 148
 149   // ClientSocketPool implementation.
 150   virtual int RequestSocket(const std::string& group_name,
 151                             const void* resolve_info,
 152                             RequestPriority priority,
 153                             ClientSocketHandle* handle,
 154                             const CompletionCallback& callback,
 155                             const BoundNetLog& net_log) OVERRIDE;
 156   virtual void RequestSockets(const std::string& group_name,
 157                               const void* params,
 158                               int num_sockets,
 159                               const BoundNetLog& net_log) OVERRIDE;
 160   virtual void CancelRequest(const std::string& group_name,
 161                              ClientSocketHandle* handle) OVERRIDE;
 162   virtual void ReleaseSocket(const std::string& group_name,
 163                              scoped_ptr<StreamSocket> socket,
 164                              int id) OVERRIDE;
 165   virtual void FlushWithError(int error) OVERRIDE;
 166   virtual void CloseIdleSockets() OVERRIDE;
 167   virtual int IdleSocketCount() const OVERRIDE;
 168   virtual int IdleSocketCountInGroup(
 169       const std::string& group_name) const OVERRIDE;
 170   virtual LoadState GetLoadState(
 171       const std::string& group_name,
 172       const ClientSocketHandle* handle) const OVERRIDE;
 173   virtual base::DictionaryValue* GetInfoAsValue(
 174       const std::string& name,
 175       const std::string& type,
 176       bool include_nested_pools) const OVERRIDE;
 177   virtual base::TimeDelta ConnectionTimeout() const OVERRIDE;
 178   virtual ClientSocketPoolHistograms* histograms() const OVERRIDE;
 179
 180   // HigherLayeredPool implementation.
 181   virtual bool IsStalled() const OVERRIDE;
 182   virtual void AddHigherLayeredPool(HigherLayeredPool* higher_pool) OVERRIDE;
 183   virtual void RemoveHigherLayeredPool(HigherLayeredPool* higher_pool) OVERRIDE;
 184
 185  private:
 186   typedef ClientSocketPoolBase<TransportSocketParams> PoolBase;
 187
 188   class TransportConnectJobFactory
 189       : public PoolBase::ConnectJobFactory {
 190    public:
 191     TransportConnectJobFactory(ClientSocketFactory* client_socket_factory,
 192                          HostResolver* host_resolver,
 193                          NetLog* net_log)
 194         : client_socket_factory_(client_socket_factory),
 195           host_resolver_(host_resolver),
 196           net_log_(net_log) {}
 197
 198     virtual ~TransportConnectJobFactory() {}
 199
 200     // ClientSocketPoolBase::ConnectJobFactory methods.
 201
 202     virtual scoped_ptr<ConnectJob> NewConnectJob(
 203         const std::string& group_name,
 204         const PoolBase::Request& request,
 205         ConnectJob::Delegate* delegate) const OVERRIDE;
 206
 207     virtual base::TimeDelta ConnectionTimeout() const OVERRIDE;
 208
 209    private:
 210     ClientSocketFactory* const client_socket_factory_;
 211     HostResolver* const host_resolver_;
 212     NetLog* net_log_;
 213
 214     DISALLOW_COPY_AND_ASSIGN(TransportConnectJobFactory);
 215   };
 216
 217   PoolBase base_;
 218
 219   DISALLOW_COPY_AND_ASSIGN(TransportClientSocketPool);
 220 };
 221
 222 }  // namespace net
 223
 224 #endif  // NET_SOCKET_TRANSPORT_CLIENT_SOCKET_POOL_H_