libbase/Socket.h

   1 // Socket.h - a virtual IO channel, for Gnash
   2 //
   3 //   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010,
   4 //   2011 Free Software Foundation, Inc
   5 //
   6 // This program is free software; you can redistribute it and/or modify
   7 // it under the terms of the GNU General Public License as published by
   8 // the Free Software Foundation; either version 3 of the License, or
   9 // (at your option) any later version.
  10 //
  11 // This program is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License
  17 // along with this program; if not, write to the Free Software
  18 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19
  20
  21 #ifndef GNASH_SOCKET_H
  22 #define GNASH_SOCKET_H
  23
  24 #include "dsodefs.h"
  25 #include <boost/cstdint.hpp>
  26 #include "IOChannel.h"
  27
  28 namespace gnash {
  29     class URL;
  30 }
  31
  32 namespace gnash {
  33
  34 /// A simple IOChannel subclass for reading and writing sockets.
  35 //
  36 /// The Socket class will give you years of satisfaction provided you observe
  37 /// the following points:
  38 /// 1. A socket is active only when both connected() and not bad().
  39 /// 2. The only accurate way of determining an error is to check bad().
  40 /// 3. read() and write() should not be called until connected() is true.
  41 class DSOEXPORT Socket : public IOChannel
  42 {
  43 public:
  44
  45     /// Create a non-connected socket.
  46     Socket();
  47
  48     virtual ~Socket() {}
  49
  50     /// Initiate a connection
  51     //
  52     /// A return of true does not mean the connection has succeeded, only that
  53     /// it did not fail. The connection attempt is only complete when
  54     /// connected() returns true.
  55     //
  56     /// @return         false if the connection fails. In this case, the
  57     ///                 Socket is still in a closed state and is ready for
  58     ///                 a new connection attempt. Otherwise true.
  59     bool connect(const std::string& hostname, boost::uint16_t port);
  60
  61     /// Close the Socket.
  62     //
  63     /// A closed Socket is in a state where another connection attempt can
  64     /// be made. Any errors are reset.
  65     void close();
  66
  67     /// Whether a connection attempt is complete.
  68     //
  69     /// This is true as soon as the socket is ready for reading and writing.
  70     /// But beware! This function may still return true if the Socket is
  71     /// in error condition. Always check bad() if you care about this.
  72     bool connected() const;
  73
  74     /// True if the Socket is in an error condition.
  75     //
  76     /// An error condition is fatal and can only be reset when the Socket
  77     /// is closed. Any read or write failure other than EAGAIN or EWOULDBLOCK
  78     /// causes a fatal error.
  79     virtual bool bad() const {
  80         return _error;
  81     }
  82
  83     /// Read exactly the given number of bytes from the Socket or none at all.
  84     //
  85     virtual std::streamsize read(void* dst, std::streamsize num);
  86
  87     /// Read up to the given number of bytes from the Socket.
  88     virtual std::streamsize readNonBlocking(void* dst, std::streamsize num);
  89
  90     /// Write the given number of bytes to the stream
  91     //
  92     /// If you call write() before connected() is true, it may put the Socket
  93     /// into an error condition.
  94     //
  95     /// Calling write() when the Socket is bad has no effect.
  96     virtual std::streamsize write(const void* src, std::streamsize num);
  97
  98     /// Return current stream position
  99     //
 100     /// Meaningless for a Socket.
 101     virtual std::streampos tell() const;
 102
 103     /// Seek to the specified position
 104     //
 105     /// Meaningless for a Socket.
 106     virtual bool seek(std::streampos p);
 107
 108     /// Seek to the end of the stream
 109     //
 110     /// Not Socket.
 111     virtual void go_to_end();
 112
 113     /// Return true if the end of the stream has been reached.
 114     //
 115     /// EOF is when remote end closed the connection and
 116     /// we have no more cached data to read
 117     ///
 118     virtual bool eof() const;
 119
 120 private:
 121
 122     /// Fill the cache.
 123     void fillCache();
 124
 125     mutable bool _connected;
 126
 127     /// A cache for received data.
 128     char _cache[16384];
 129
 130     /// The socket ID.
 131     int _socket;
 132
 133     /// Unprocessed bytes.
 134     int _size;
 135
 136     /// Current read position in cache.
 137     size_t _pos;
 138
 139     mutable bool _error;
 140 };
 141
 142 } // namespace gnash
 143
 144 #endif // GNASH_IOCHANNEL_H
 145
 146
 147 // Local Variables:
 148 // mode: C++
 149 // indent-tabs-mode: t
 150 // End: