include/libtorrent/extensions.hpp

   1 /*
   2
   3 Copyright (c) 2006, Arvid Norberg
   4 All rights reserved.
   5
   6 Redistribution and use in source and binary forms, with or without
   7 modification, are permitted provided that the following conditions
   8 are met:
   9
  10     * Redistributions of source code must retain the above copyright
  11       notice, this list of conditions and the following disclaimer.
  12     * Redistributions in binary form must reproduce the above copyright
  13       notice, this list of conditions and the following disclaimer in
  14       the documentation and/or other materials provided with the distribution.
  15     * Neither the name of the author nor the names of its
  16       contributors may be used to endorse or promote products derived
  17       from this software without specific prior written permission.
  18
  19 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  20 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  23 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29 POSSIBILITY OF SUCH DAMAGE.
  30
  31 */
  32
  33 #ifndef TORRENT_EXTENSIONS_HPP_INCLUDED
  34 #define TORRENT_EXTENSIONS_HPP_INCLUDED
  35
  36 #ifndef TORRENT_DISABLE_EXTENSIONS
  37
  38 #ifdef _MSC_VER
  39 #pragma warning(push, 1)
  40 #endif
  41
  42 #include <boost/shared_ptr.hpp>
  43
  44 #ifdef _MSC_VER
  45 #pragma warning(pop)
  46 #endif
  47
  48 #include <vector>
  49 #include "libtorrent/config.hpp"
  50 #include "libtorrent/buffer.hpp"
  51
  52 namespace libtorrent
  53 {
  54         struct peer_plugin;
  55         class bt_peer_connection;
  56         struct peer_request;
  57         class peer_connection;
  58         class entry;
  59         struct lazy_entry;
  60         struct disk_buffer_holder;
  61         struct bitfield;
  62
  63         struct TORRENT_EXPORT torrent_plugin
  64         {
  65                 virtual ~torrent_plugin() {}
  66                 // throwing an exception closes the connection
  67                 // returning a 0 pointer is valid and will not add
  68                 // the peer_plugin to the peer_connection
  69                 virtual boost::shared_ptr<peer_plugin> new_connection(peer_connection*)
  70                 { return boost::shared_ptr<peer_plugin>(); }
  71
  72                 virtual void on_piece_pass(int index) {}
  73                 virtual void on_piece_failed(int index) {}
  74
  75                 // called aproximately once every second
  76                 virtual void tick() {}
  77
  78                 // if true is returned, it means the handler handled the event,
  79                 // and no other plugins will have their handlers called, and the
  80                 // default behavior will be skipped
  81                 virtual bool on_pause() { return false; }
  82                 virtual bool on_resume() { return false;}
  83
  84                 // this is called when the initial checking of
  85                 // files is completed.
  86                 virtual void on_files_checked() {}
  87         };
  88
  89         struct TORRENT_EXPORT peer_plugin
  90         {
  91                 virtual ~peer_plugin() {}
  92
  93                 // can add entries to the extension handshake
  94                 // this is not called for web seeds
  95                 virtual void add_handshake(entry&) {}
  96
  97                 // throwing an exception from any of the handlers (except add_handshake)
  98                 // closes the connection
  99
 100                 // this is called when the initial BT handshake is received. Returning false
 101                 // means that the other end doesn't support this extension and will remove
 102                 // it from the list of plugins.
 103                 // this is not called for web seeds
 104                 virtual bool on_handshake(char const* reserved_bits) { return true; }
 105
 106                 // called when the extension handshake from the other end is received
 107                 // if this returns false, it means that this extension isn't
 108                 // supported by this peer. It will result in this peer_plugin
 109                 // being removed from the peer_connection and destructed.
 110                 // this is not called for web seeds
 111                 virtual bool on_extension_handshake(lazy_entry const& h) { return true; }
 112
 113                 // returning true from any of the message handlers
 114                 // indicates that the plugin has handeled the message.
 115                 // it will break the plugin chain traversing and not let
 116                 // anyone else handle the message, including the default
 117                 // handler.
 118
 119                 virtual bool on_choke()
 120                 { return false; }
 121
 122                 virtual bool on_unchoke()
 123                 { return false; }
 124
 125                 virtual bool on_interested()
 126                 { return false; }
 127
 128                 virtual bool on_not_interested()
 129                 { return false; }
 130
 131                 virtual bool on_have(int index)
 132                 { return false; }
 133
 134                 virtual bool on_bitfield(bitfield const& bitfield)
 135                 { return false; }
 136
 137                 virtual bool on_have_all()
 138                 { return false; }
 139
 140                 virtual bool on_have_none()
 141                 { return false; }
 142
 143                 virtual bool on_allowed_fast(int index)
 144                 { return false; }
 145
 146                 virtual bool on_request(peer_request const& req)
 147                 { return false; }
 148
 149                 virtual bool on_piece(peer_request const& piece, disk_buffer_holder& data)
 150                 { return false; }
 151
 152                 virtual bool on_cancel(peer_request const& req)
 153                 { return false; }
 154
 155                 virtual bool on_reject(peer_request const& req)
 156                 { return false; }
 157
 158                 virtual bool on_suggest(int index)
 159                 { return false; }
 160
 161                 // called when an extended message is received. If returning true,
 162                 // the message is not processed by any other plugin and if false
 163                 // is returned the next plugin in the chain will receive it to
 164                 // be able to handle it
 165                 // this is not called for web seeds
 166                 virtual bool on_extended(int length
 167                         , int msg, buffer::const_interval body)
 168                 { return false; }
 169
 170                 // this is not called for web seeds
 171                 virtual bool on_unknown_message(int length, int msg
 172                         , buffer::const_interval body)
 173                 { return false; }
 174
 175                 // called when a piece that this peer participated in either
 176                 // fails or passes the hash_check
 177                 virtual void on_piece_pass(int index) {}
 178                 virtual void on_piece_failed(int index) {}
 179
 180                 // called aproximately once every second
 181                 virtual void tick() {}
 182
 183                 // called each time a request message is to be sent. If true
 184                 // is returned, the original request message won't be sent and
 185                 // no other plugin will have this function called.
 186                 virtual bool write_request(peer_request const& r) { return false; }
 187         };
 188
 189 }
 190
 191 #endif
 192
 193 #endif // TORRENT_EXTENSIONS_HPP_INCLUDED
 194