2 -- Implementation of the DCC protocol
5 local irc = require 'irc'
6 local irc_debug = require 'irc.debug'
7 local misc = require 'irc.misc'
8 local socket = require 'socket'
9 local coroutine = require 'coroutine'
10 local io = require 'io'
11 local string = require 'string'
15 -- This module implements the DCC protocol. File transfers (DCC SEND) are
16 -- handled, but DCC CHAT is not, as of yet.
24 -- private functions {{{
27 -- Sends a file to a remote user, after that user has accepted our DCC SEND
29 -- @param sock Socket to send the file on
30 -- @param file Lua file object corresponding to the file we want to send
31 -- @param size Size of the file to send
32 -- @param packet_size Size of the packets to send the file in
33 local function send_file(sock, file, size, packet_size)
36 local packet = file:read(packet_size)
37 if not packet then break end
38 bytes = bytes + packet:len()
41 sock:send(packet, index)
42 local new_bytes = misc.int_to_str(sock:receive(4))
43 if new_bytes ~= bytes then
44 index = packet_size - bytes + new_bytes + 1
49 if bytes >= size then break end
54 irc._unregister_socket(sock, 'w')
61 -- Handle the connection attempt by a remote user to get our file. Basically
62 -- just swaps out the server socket we were listening on for a client socket
63 -- that we can send data on
64 -- @param ssock Server socket that the remote user connected to
65 -- @param file Lua file object corresponding to the file we want to send
66 -- @param size Size of the file to send
67 -- @param packet_size Size of the packets to send the file in
68 local function handle_connect(ssock, file, size, packet_size)
69 packet_size = packet_size or 1024
70 local sock = ssock:accept()
73 irc._unregister_socket(ssock, 'r')
74 irc._register_socket(sock, 'w',
75 coroutine.wrap(function(sock)
76 return send_file(sock, file, size, packet_size)
84 -- Accepts a file from a remote user which has offered it to us.
85 -- @param sock Socket to receive the file on
86 -- @param file Lua file object corresponding to the file we want to save
87 -- @param size Size of the file we are receiving
88 -- @param packet_size Size of the packets to receive the file in
89 local function accept_file(sock, file, size, packet_size)
92 local packet, err, partial_packet = sock:receive(packet_size)
93 if not packet and err == "timeout" then packet = partial_packet end
94 if not packet then break end
95 if packet:len() == 0 then break end
96 bytes = bytes + packet:len()
97 sock:send(misc.str_to_int(bytes))
103 irc._unregister_socket(sock, 'r')
109 -- public functions {{{
112 -- Offers a file to a remote user.
113 -- @param nick User to offer the file to
114 -- @param filename Filename to offer
115 -- @param port Port to accept connections on (optional, defaults to
116 -- choosing an available port between FIRST_PORT and LAST_PORT
118 function send(nick, filename, port)
119 port = port or FIRST_PORT
120 local sock = base.assert(socket.tcp())
122 err, msg = sock:bind('*', port)
124 until msg ~= "address already in use" and port <= LAST_PORT + 1
125 base.assert(err, msg)
126 base.assert(sock:listen(1))
127 local ip = misc.ip_str_to_int(irc.get_ip())
128 local file = base.assert(io.open(filename))
129 local size = file:seek("end")
131 irc._register_socket(sock, 'r',
132 coroutine.wrap(function(sock)
133 return handle_connect(sock, file, size)
135 filename = misc.basename(filename)
136 if filename:find(" ") then filename = '"' .. filename .. '"' end
137 irc.send("PRIVMSG", nick, {"DCC SEND " .. filename .. " " ..
138 ip .. " " .. port - 1 .. " " .. size})
144 -- Accepts a file offer from a remote user. Called when the on_dcc callback
146 -- @param filename Name to save the file as
147 -- @param address IP address of the remote user
148 -- @param port Port to connect to at the remote user
149 -- @param size Size of the file that the remote user is offering
150 -- @param packet_size Size of the packets the remote user will be sending
151 function accept(filename, address, port, size, packet_size)
152 packet_size = packet_size or 1024
153 local sock = base.assert(socket.tcp())
154 base.assert(sock:connect(misc.ip_int_to_str(address), port))
156 local file = base.assert(io.open(misc.get_unique_filename(filename), "w"))
157 irc._register_socket(sock, 'r',
158 coroutine.wrap(function(sock)
159 return accept_file(sock, file, size, packet_size)