henrike@webrtc.org | f7795df | 2014-05-13 18:00:26 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2004 The WebRTC Project Authors. All rights reserved. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license |
| 5 | * that can be found in the LICENSE file in the root of the source |
| 6 | * tree. An additional intellectual property rights grant can be found |
| 7 | * in the file PATENTS. All contributing project authors may |
| 8 | * be found in the AUTHORS file in the root of the source tree. |
| 9 | */ |
| 10 | |
| 11 | #ifndef WEBRTC_BASE_VIRTUALSOCKETSERVER_H_ |
| 12 | #define WEBRTC_BASE_VIRTUALSOCKETSERVER_H_ |
| 13 | |
| 14 | #include <assert.h> |
| 15 | |
| 16 | #include <deque> |
| 17 | #include <map> |
| 18 | |
| 19 | #include "webrtc/base/messagequeue.h" |
| 20 | #include "webrtc/base/socketserver.h" |
| 21 | |
| 22 | namespace rtc { |
| 23 | |
| 24 | class VirtualSocket; |
| 25 | class SocketAddressPair; |
| 26 | |
| 27 | // Simulates a network in the same manner as a loopback interface. The |
| 28 | // interface can create as many addresses as you want. All of the sockets |
| 29 | // created by this network will be able to communicate with one another, unless |
| 30 | // they are bound to addresses from incompatible families. |
| 31 | class VirtualSocketServer : public SocketServer, public sigslot::has_slots<> { |
| 32 | public: |
| 33 | // TODO: Add "owned" parameter. |
| 34 | // If "owned" is set, the supplied socketserver will be deleted later. |
| 35 | explicit VirtualSocketServer(SocketServer* ss); |
| 36 | virtual ~VirtualSocketServer(); |
| 37 | |
| 38 | SocketServer* socketserver() { return server_; } |
| 39 | |
| 40 | // Limits the network bandwidth (maximum bytes per second). Zero means that |
| 41 | // all sends occur instantly. Defaults to 0. |
| 42 | uint32 bandwidth() const { return bandwidth_; } |
| 43 | void set_bandwidth(uint32 bandwidth) { bandwidth_ = bandwidth; } |
| 44 | |
| 45 | // Limits the amount of data which can be in flight on the network without |
| 46 | // packet loss (on a per sender basis). Defaults to 64 KB. |
| 47 | uint32 network_capacity() const { return network_capacity_; } |
| 48 | void set_network_capacity(uint32 capacity) { |
| 49 | network_capacity_ = capacity; |
| 50 | } |
| 51 | |
| 52 | // The amount of data which can be buffered by tcp on the sender's side |
| 53 | uint32 send_buffer_capacity() const { return send_buffer_capacity_; } |
| 54 | void set_send_buffer_capacity(uint32 capacity) { |
| 55 | send_buffer_capacity_ = capacity; |
| 56 | } |
| 57 | |
| 58 | // The amount of data which can be buffered by tcp on the receiver's side |
| 59 | uint32 recv_buffer_capacity() const { return recv_buffer_capacity_; } |
| 60 | void set_recv_buffer_capacity(uint32 capacity) { |
| 61 | recv_buffer_capacity_ = capacity; |
| 62 | } |
| 63 | |
| 64 | // Controls the (transit) delay for packets sent in the network. This does |
| 65 | // not inclue the time required to sit in the send queue. Both of these |
| 66 | // values are measured in milliseconds. Defaults to no delay. |
| 67 | uint32 delay_mean() const { return delay_mean_; } |
| 68 | uint32 delay_stddev() const { return delay_stddev_; } |
| 69 | uint32 delay_samples() const { return delay_samples_; } |
| 70 | void set_delay_mean(uint32 delay_mean) { delay_mean_ = delay_mean; } |
| 71 | void set_delay_stddev(uint32 delay_stddev) { |
| 72 | delay_stddev_ = delay_stddev; |
| 73 | } |
| 74 | void set_delay_samples(uint32 delay_samples) { |
| 75 | delay_samples_ = delay_samples; |
| 76 | } |
| 77 | |
| 78 | // If the (transit) delay parameters are modified, this method should be |
| 79 | // called to recompute the new distribution. |
| 80 | void UpdateDelayDistribution(); |
| 81 | |
| 82 | // Controls the (uniform) probability that any sent packet is dropped. This |
| 83 | // is separate from calculations to drop based on queue size. |
| 84 | double drop_probability() { return drop_prob_; } |
| 85 | void set_drop_probability(double drop_prob) { |
| 86 | assert((0 <= drop_prob) && (drop_prob <= 1)); |
| 87 | drop_prob_ = drop_prob; |
| 88 | } |
| 89 | |
| 90 | // SocketFactory: |
| 91 | virtual Socket* CreateSocket(int type); |
| 92 | virtual Socket* CreateSocket(int family, int type); |
| 93 | |
| 94 | virtual AsyncSocket* CreateAsyncSocket(int type); |
| 95 | virtual AsyncSocket* CreateAsyncSocket(int family, int type); |
| 96 | |
| 97 | // SocketServer: |
| 98 | virtual void SetMessageQueue(MessageQueue* queue); |
| 99 | virtual bool Wait(int cms, bool process_io); |
| 100 | virtual void WakeUp(); |
| 101 | |
| 102 | typedef std::pair<double, double> Point; |
| 103 | typedef std::vector<Point> Function; |
| 104 | |
| 105 | static Function* CreateDistribution(uint32 mean, uint32 stddev, |
| 106 | uint32 samples); |
| 107 | |
| 108 | // Similar to Thread::ProcessMessages, but it only processes messages until |
| 109 | // there are no immediate messages or pending network traffic. Returns false |
| 110 | // if Thread::Stop() was called. |
| 111 | bool ProcessMessagesUntilIdle(); |
| 112 | |
| 113 | protected: |
| 114 | // Returns a new IP not used before in this network. |
| 115 | IPAddress GetNextIP(int family); |
| 116 | uint16 GetNextPort(); |
| 117 | |
| 118 | VirtualSocket* CreateSocketInternal(int family, int type); |
| 119 | |
| 120 | // Binds the given socket to addr, assigning and IP and Port if necessary |
| 121 | int Bind(VirtualSocket* socket, SocketAddress* addr); |
| 122 | |
| 123 | // Binds the given socket to the given (fully-defined) address. |
| 124 | int Bind(VirtualSocket* socket, const SocketAddress& addr); |
| 125 | |
| 126 | // Find the socket bound to the given address |
| 127 | VirtualSocket* LookupBinding(const SocketAddress& addr); |
| 128 | |
| 129 | int Unbind(const SocketAddress& addr, VirtualSocket* socket); |
| 130 | |
| 131 | // Adds a mapping between this socket pair and the socket. |
| 132 | void AddConnection(const SocketAddress& client, |
| 133 | const SocketAddress& server, |
| 134 | VirtualSocket* socket); |
| 135 | |
| 136 | // Find the socket pair corresponding to this server address. |
| 137 | VirtualSocket* LookupConnection(const SocketAddress& client, |
| 138 | const SocketAddress& server); |
| 139 | |
| 140 | void RemoveConnection(const SocketAddress& client, |
| 141 | const SocketAddress& server); |
| 142 | |
| 143 | // Connects the given socket to the socket at the given address |
| 144 | int Connect(VirtualSocket* socket, const SocketAddress& remote_addr, |
| 145 | bool use_delay); |
| 146 | |
| 147 | // Sends a disconnect message to the socket at the given address |
| 148 | bool Disconnect(VirtualSocket* socket); |
| 149 | |
| 150 | // Sends the given packet to the socket at the given address (if one exists). |
| 151 | int SendUdp(VirtualSocket* socket, const char* data, size_t data_size, |
| 152 | const SocketAddress& remote_addr); |
| 153 | |
| 154 | // Moves as much data as possible from the sender's buffer to the network |
| 155 | void SendTcp(VirtualSocket* socket); |
| 156 | |
| 157 | // Places a packet on the network. |
| 158 | void AddPacketToNetwork(VirtualSocket* socket, VirtualSocket* recipient, |
| 159 | uint32 cur_time, const char* data, size_t data_size, |
| 160 | size_t header_size, bool ordered); |
| 161 | |
| 162 | // Removes stale packets from the network |
| 163 | void PurgeNetworkPackets(VirtualSocket* socket, uint32 cur_time); |
| 164 | |
| 165 | // Computes the number of milliseconds required to send a packet of this size. |
| 166 | uint32 SendDelay(uint32 size); |
| 167 | |
| 168 | // Returns a random transit delay chosen from the appropriate distribution. |
| 169 | uint32 GetRandomTransitDelay(); |
| 170 | |
| 171 | // Basic operations on functions. Those that return a function also take |
| 172 | // ownership of the function given (and hence, may modify or delete it). |
| 173 | static Function* Accumulate(Function* f); |
| 174 | static Function* Invert(Function* f); |
| 175 | static Function* Resample(Function* f, double x1, double x2, uint32 samples); |
| 176 | static double Evaluate(Function* f, double x); |
| 177 | |
| 178 | // NULL out our message queue if it goes away. Necessary in the case where |
| 179 | // our lifetime is greater than that of the thread we are using, since we |
| 180 | // try to send Close messages for all connected sockets when we shutdown. |
| 181 | void OnMessageQueueDestroyed() { msg_queue_ = NULL; } |
| 182 | |
| 183 | // Determine if two sockets should be able to communicate. |
| 184 | // We don't (currently) specify an address family for sockets; instead, |
| 185 | // the currently bound address is used to infer the address family. |
| 186 | // Any socket that is not explicitly bound to an IPv4 address is assumed to be |
| 187 | // dual-stack capable. |
| 188 | // This function tests if two addresses can communicate, as well as the |
| 189 | // sockets to which they may be bound (the addresses may or may not yet be |
| 190 | // bound to the sockets). |
| 191 | // First the addresses are tested (after normalization): |
| 192 | // If both have the same family, then communication is OK. |
| 193 | // If only one is IPv4 then false, unless the other is bound to ::. |
| 194 | // This applies even if the IPv4 address is 0.0.0.0. |
| 195 | // The socket arguments are optional; the sockets are checked to see if they |
| 196 | // were explicitly bound to IPv6-any ('::'), and if so communication is |
| 197 | // permitted. |
| 198 | // NB: This scheme doesn't permit non-dualstack IPv6 sockets. |
| 199 | static bool CanInteractWith(VirtualSocket* local, VirtualSocket* remote); |
| 200 | |
| 201 | private: |
| 202 | friend class VirtualSocket; |
| 203 | |
| 204 | typedef std::map<SocketAddress, VirtualSocket*> AddressMap; |
| 205 | typedef std::map<SocketAddressPair, VirtualSocket*> ConnectionMap; |
| 206 | |
| 207 | SocketServer* server_; |
| 208 | bool server_owned_; |
| 209 | MessageQueue* msg_queue_; |
| 210 | bool stop_on_idle_; |
| 211 | uint32 network_delay_; |
| 212 | in_addr next_ipv4_; |
| 213 | in6_addr next_ipv6_; |
| 214 | uint16 next_port_; |
| 215 | AddressMap* bindings_; |
| 216 | ConnectionMap* connections_; |
| 217 | |
| 218 | uint32 bandwidth_; |
| 219 | uint32 network_capacity_; |
| 220 | uint32 send_buffer_capacity_; |
| 221 | uint32 recv_buffer_capacity_; |
| 222 | uint32 delay_mean_; |
| 223 | uint32 delay_stddev_; |
| 224 | uint32 delay_samples_; |
| 225 | Function* delay_dist_; |
| 226 | CriticalSection delay_crit_; |
| 227 | |
| 228 | double drop_prob_; |
| 229 | DISALLOW_EVIL_CONSTRUCTORS(VirtualSocketServer); |
| 230 | }; |
| 231 | |
| 232 | } // namespace rtc |
| 233 | |
| 234 | #endif // WEBRTC_BASE_VIRTUALSOCKETSERVER_H_ |