net/tools/quic/quic_socket_utils.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 // Some socket related helper methods for quic.
   6
   7 #ifndef NET_TOOLS_QUIC_QUIC_SOCKET_UTILS_H_
   8 #define NET_TOOLS_QUIC_QUIC_SOCKET_UTILS_H_
   9
  10 #include <stddef.h>
  11 #include <sys/socket.h>
  12 #include <string>
  13
  14 #include "base/basictypes.h"
  15 #include "net/base/ip_endpoint.h"
  16 #include "net/quic/quic_types.h"
  17
  18 namespace net {
  19 namespace tools {
  20
  21 class QuicSocketUtils {
  22  public:
  23   // If the msghdr contains IP_PKTINFO or IPV6_PKTINFO, this will return the
  24   // IPAddressNumber in that header.  Returns an uninitialized IPAddress on
  25   // failure.
  26   static IPAddressNumber GetAddressFromMsghdr(struct msghdr *hdr);
  27
  28   // If the msghdr contains an SO_RXQ_OVFL entry, this will set dropped_packets
  29   // to the correct value and return true. Otherwise it will return false.
  30   static bool GetOverflowFromMsghdr(struct msghdr *hdr,
  31                                     uint32 *dropped_packets);
  32
  33   // Sets either IP_PKTINFO or IPV6_PKTINFO on the socket, based on
  34   // address_family.  Returns the return code from setsockopt.
  35   static int SetGetAddressInfo(int fd, int address_family);
  36
  37   // Sets the send buffer size to |size| and returns false if it fails.
  38   static bool SetSendBufferSize(int fd, size_t size);
  39
  40   // Sets the receive buffer size to |size| and returns false if it fails.
  41   static bool SetReceiveBufferSize(int fd, size_t size);
  42
  43   // Reads buf_len from the socket.  If reading is successful, returns bytes
  44   // read and sets peer_address to the peer address.  Otherwise returns -1.
  45   //
  46   // If dropped_packets is non-null, it will be set to the number of packets
  47   // dropped on the socket since the socket was created, assuming the kernel
  48   // supports this feature.
  49   //
  50   // If self_address is non-null, it will be set to the address the peer sent
  51   // packets to, assuming a packet was read.
  52   static int ReadPacket(int fd,
  53                         char* buffer,
  54                         size_t buf_len,
  55                         uint32* dropped_packets,
  56                         IPAddressNumber* self_address,
  57                         IPEndPoint* peer_address);
  58
  59   // Writes buf_len to the socket. If writing is successful, sets the result's
  60   // status to WRITE_STATUS_OK and sets bytes_written.  Otherwise sets the
  61   // result's status to WRITE_STATUS_BLOCKED or WRITE_STATUS_ERROR and sets
  62   // error_code to errno.
  63   static WriteResult WritePacket(int fd,
  64                                  const char* buffer,
  65                                  size_t buf_len,
  66                                  const IPAddressNumber& self_address,
  67                                  const IPEndPoint& peer_address);
  68
  69   // A helper for WritePacket which fills in the cmsg with the supplied self
  70   // address.
  71   // Returns the length of the packet info structure used.
  72   static size_t SetIpInfoInCmsg(const IPAddressNumber& self_address,
  73                                 cmsghdr* cmsg);
  74
  75  private:
  76   DISALLOW_COPY_AND_ASSIGN(QuicSocketUtils);
  77 };
  78
  79 }  // namespace tools
  80 }  // namespace net
  81
  82 #endif  // NET_TOOLS_QUIC_QUIC_SOCKET_UTILS_H_