tools/android/forwarder2/socket.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 TOOLS_ANDROID_FORWARDER2_SOCKET_H_
   6 #define TOOLS_ANDROID_FORWARDER2_SOCKET_H_
   7
   8 #include <fcntl.h>
   9 #include <netinet/in.h>
  10 #include <sys/socket.h>
  11 #include <sys/un.h>
  12
  13 #include <string>
  14 #include <vector>
  15
  16 #include "base/basictypes.h"
  17
  18 namespace forwarder2 {
  19
  20 // Wrapper class around unix socket api.  Can be used to create, bind or
  21 // connect to both Unix domain sockets and TCP sockets.
  22 // TODO(pliard): Split this class into TCPSocket and UnixDomainSocket.
  23 class Socket {
  24  public:
  25   Socket();
  26   ~Socket();
  27
  28   bool BindUnix(const std::string& path);
  29   bool BindTcp(const std::string& host, int port);
  30   bool ConnectUnix(const std::string& path);
  31   bool ConnectTcp(const std::string& host, int port);
  32
  33   // Just a wrapper around unix socket shutdown(), see man 2 shutdown.
  34   void Shutdown();
  35
  36   // Just a wrapper around unix socket close(), see man 2 close.
  37   void Close();
  38   bool IsClosed() const { return socket_ < 0; }
  39
  40   int fd() const { return socket_; }
  41
  42   bool Accept(Socket* new_socket);
  43
  44   // Returns the port allocated to this socket or zero on error.
  45   int GetPort();
  46
  47   // Just a wrapper around unix read() function.
  48   // Reads up to buffer_size, but may read less then buffer_size.
  49   // Returns the number of bytes read.
  50   int Read(void* buffer, size_t buffer_size);
  51
  52   // Non-blocking version of Read() above. This must be called after a
  53   // successful call to select(). The socket must also be in non-blocking mode
  54   // before calling this method.
  55   int NonBlockingRead(void* buffer, size_t buffer_size);
  56
  57   // Wrapper around send().
  58   int Write(const void* buffer, size_t count);
  59
  60   // Same as NonBlockingRead() but for writing.
  61   int NonBlockingWrite(const void* buffer, size_t count);
  62
  63   // Calls Read() multiple times until num_bytes is written to the provided
  64   // buffer. No bounds checking is performed.
  65   // Returns number of bytes read, which can be different from num_bytes in case
  66   // of errror.
  67   int ReadNumBytes(void* buffer, size_t num_bytes);
  68
  69   // Calls Write() multiple times until num_bytes is written. No bounds checking
  70   // is performed. Returns number of bytes written, which can be different from
  71   // num_bytes in case of errror.
  72   int WriteNumBytes(const void* buffer, size_t num_bytes);
  73
  74   // Calls WriteNumBytes for the given std::string. Note that the null
  75   // terminator is not written to the socket.
  76   int WriteString(const std::string& buffer);
  77
  78   bool has_error() const { return socket_error_; }
  79
  80   // |event_fd| must be a valid pipe file descriptor created from the
  81   // PipeNotifier and must live (not be closed) at least as long as this socket
  82   // is alive.
  83   void AddEventFd(int event_fd);
  84
  85   // Returns whether Accept() or Connect() was interrupted because the socket
  86   // received an external event fired through the provided fd.
  87   bool DidReceiveEventOnFd(int fd) const;
  88
  89   bool DidReceiveEvent() const;
  90
  91   static pid_t GetUnixDomainSocketProcessOwner(const std::string& path);
  92
  93  private:
  94   enum EventType {
  95     READ,
  96     WRITE
  97   };
  98
  99   union SockAddr {
 100     // IPv4 sockaddr
 101     sockaddr_in addr4;
 102     // IPv6 sockaddr
 103     sockaddr_in6 addr6;
 104     // Unix Domain sockaddr
 105     sockaddr_un addr_un;
 106   };
 107
 108   struct Event {
 109     int fd;
 110     bool was_fired;
 111   };
 112
 113   bool SetNonBlocking();
 114
 115   // If |host| is empty, use localhost.
 116   bool InitTcpSocket(const std::string& host, int port);
 117   bool InitUnixSocket(const std::string& path);
 118   bool BindAndListen();
 119   bool Connect();
 120
 121   bool Resolve(const std::string& host);
 122   bool InitSocketInternal();
 123   void SetSocketError();
 124
 125   // Waits until either the Socket or the |exit_notifier_fd_| has received an
 126   // event.
 127   bool WaitForEvent(EventType type, int timeout_secs);
 128
 129   int socket_;
 130   int port_;
 131   bool socket_error_;
 132
 133   // Family of the socket (PF_INET, PF_INET6 or PF_UNIX).
 134   int family_;
 135
 136   SockAddr addr_;
 137
 138   // Points to one of the members of the above union depending on the family.
 139   sockaddr* addr_ptr_;
 140   // Length of one of the members of the above union depending on the family.
 141   socklen_t addr_len_;
 142
 143   // Used to listen for external events (e.g. process received a SIGTERM) while
 144   // blocking on I/O operations.
 145   std::vector<Event> events_;
 146
 147   DISALLOW_COPY_AND_ASSIGN(Socket);
 148 };
 149
 150 }  // namespace forwarder
 151
 152 #endif  // TOOLS_ANDROID_FORWARDER2_SOCKET_H_