Allow p2p UDP packages to set DSCP

net/udp/udp_socket_libevent.h

 // Copyright (c) 2012 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_UDP_UDP_SOCKET_LIBEVENT_H_
 #define NET_UDP_UDP_SOCKET_LIBEVENT_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/threading/non_thread_safe.h"
 #include "net/base/completion_callback.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
 #include "net/base/rand_callback.h"
 #include "net/udp/datagram_socket.h"
 
 namespace net {
 
 class NET_EXPORT UDPSocketLibevent : public base::NonThreadSafe {
  public:
-  UDPSocketLibevent(DatagramSocket::BindType bind_type,
+ UDPSocketLibevent(DatagramSocket::BindType bind_type,
                     const RandIntCallback& rand_int_cb,
                     net::NetLog* net_log,
                     const net::NetLog::Source& source);
   virtual ~UDPSocketLibevent();
 
   // Connect the socket to connect with a certain |address|.
   // Returns a net error code.
   int Connect(const IPEndPoint& address);
 
   // Bind the address/port for this socket to |address|.  This is generally
@@ skipping 109 matching lines @@
   // Note: the behavior of |SetMulticastLoopbackMode| is slightly
   // different between Windows and Unix-like systems. The inconsistency only
   // happens when there are more than one applications on the same host
   // joined to the same multicast group while having different settings on
   // multicast loopback mode. On Windows, the applications with loopback off
   // will not RECEIVE the loopback packets; while on Unix-like systems, the
   // applications with loopback off will not SEND the loopback packets to
   // other applications on the same host. See MSDN: http://goo.gl/6vqbj
   int SetMulticastLoopbackMode(bool loopback);
 
+  // Set the differentiated services flags on outgoing packets. May not
+  // do anything on some platforms.
+  // Some useful values:
+  //  46 (Expedited Forwarding) for telephony
+  //  34 (AF4) for interactive multimedia
+  //  26 (AF3) multimedia streaming
+  //  10 (AF1) bulk transfers
+  int SetToS(int dscp);

[Alpha Left Google, 2013/08/07 00:45:16]

Should we provide a enum include file that lists all the QoS values instead of
just an int.

[hubbe, 2013/08/07 17:20:35]

Done.

+
  private:
   static const int kInvalidSocket = -1;
 
   enum SocketOptions {
     SOCKET_OPTION_REUSE_ADDRESS  = 1 << 0,
     SOCKET_OPTION_BROADCAST      = 1 << 1,
     SOCKET_OPTION_MULTICAST_LOOP = 1 << 2
   };
 
   class ReadWatcher : public base::MessageLoopForIO::Watcher {
@@ skipping 62 matching lines @@
   int DoBind(const IPEndPoint& address);
   int RandomBind(const IPEndPoint& address);
 
   int socket_;
   int addr_family_;
 
   // Bitwise-or'd combination of SocketOptions. Specifies the set of
   // options that should be applied to |socket_| before Bind().
   int socket_options_;
 
+  // Differentiated Services Code Point.
+  int dscp_;
+
   // Multicast socket options cached for SetSocketOption.
   // Cannot be used after Bind().
   int multicast_time_to_live_;
 
   // How to do source port binding, used only when UDPSocket is part of
   // UDPClientSocket, since UDPServerSocket provides Bind.
   DatagramSocket::BindType bind_type_;
 
   // PRNG function for generating port numbers.
   RandIntCallback rand_int_cb_;
@@ skipping 28 matching lines @@
   CompletionCallback write_callback_;
 
   BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(UDPSocketLibevent);
 };
 
 }  // namespace net
 
 #endif  // NET_UDP_UDP_SOCKET_LIBEVENT_H_