--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/etc/lp.lua	Tue Aug 26 18:40:01 2008 -0700
@@ -0,0 +1,324 @@
+-----------------------------------------------------------------------------
+-- LPD support for the Lua language
+-- LuaSocket toolkit.
+-- Author: David Burgess
+-- Modified by Diego Nehab, but David is in charge
+-- RCS ID: $Id: lp.lua,v 1.14 2005/11/21 07:04:44 diego Exp $
+-----------------------------------------------------------------------------
+--[[
+     if you have any questions: RFC 1179
+]]
+-- make sure LuaSocket is loaded
+local io = require("io")
+local base = _G
+local os = require("os")
+local math = require("math")
+local string = require("string")
+local socket = require("socket")
+local ltn12 = require("ltn12")
+module("socket.lp")
+
+-- default port
+PORT = 515
+SERVER = os.getenv("SERVER_NAME") or os.getenv("COMPUTERNAME") or "localhost"
+PRINTER = os.getenv("PRINTER") or "printer"
+
+local function connect(localhost, option)
+    local host = option.host or SERVER
+    local port = option.port or PORT
+    local skt
+    local try = socket.newtry(function() if skt then skt:close() end end)
+    if option.localbind then
+        -- bind to a local port (if we can)
+        local localport = 721
+        local done, err
+        repeat
+            skt = socket.try(socket.tcp())
+            try(skt:settimeout(30))
+            done, err = skt:bind(localhost, localport)
+            if not done then
+                localport = localport + 1
+                skt:close()
+                skt = nil
+            else break end
+        until localport > 731
+        socket.try(skt, err)
+    else skt = socket.try(socket.tcp()) end
+    try(skt:connect(host, port))
+    return { skt = skt, try = try }
+end
+
+--[[
+RFC 1179
+5.3 03 - Send queue state (short)
+
+      +----+-------+----+------+----+
+      | 03 | Queue | SP | List | LF |
+      +----+-------+----+------+----+
+      Command code - 3
+      Operand 1 - Printer queue name
+      Other operands - User names or job numbers
+
+   If the user names or job numbers or both are supplied then only those
+   jobs for those users or with those numbers will be sent.
+
+   The response is an ASCII stream which describes the printer queue.
+   The stream continues until the connection closes.  Ends of lines are
+   indicated with ASCII LF control characters.  The lines may also
+   contain ASCII HT control characters.
+
+5.4 04 - Send queue state (long)
+
+      +----+-------+----+------+----+
+      | 04 | Queue | SP | List | LF |
+      +----+-------+----+------+----+
+      Command code - 4
+      Operand 1 - Printer queue name
+      Other operands - User names or job numbers
+
+   If the user names or job numbers or both are supplied then only those
+   jobs for those users or with those numbers will be sent.
+
+   The response is an ASCII stream which describes the printer queue.
+   The stream continues until the connection closes.  Ends of lines are
+   indicated with ASCII LF control characters.  The lines may also
+   contain ASCII HT control characters.
+]]
+
+-- gets server acknowledement
+local function recv_ack(con)
+  local ack = con.skt:receive(1)
+  con.try(string.char(0) == ack, "failed to receive server acknowledgement")
+end
+
+-- sends client acknowledement
+local function send_ack(con)
+  local sent = con.skt:send(string.char(0))
+  con.try(sent == 1, "failed to send acknowledgement")
+end
+
+-- sends queue request
+-- 5.2 02 - Receive a printer job
+--
+--       +----+-------+----+
+--       | 02 | Queue | LF |
+--       +----+-------+----+
+--       Command code - 2
+--       Operand - Printer queue name
+--
+--    Receiving a job is controlled by a second level of commands.  The
+--    daemon is given commands by sending them over the same connection.
+--    The commands are described in the next section (6).
+--
+--    After this command is sent, the client must read an acknowledgement
+--    octet from the daemon.  A positive acknowledgement is an octet of
+--    zero bits.  A negative acknowledgement is an octet of any other
+--    pattern.
+local function send_queue(con, queue)
+  queue = queue or PRINTER
+  local str = string.format("\2%s\10", queue)
+  local sent = con.skt:send(str)
+  con.try(sent == string.len(str), "failed to send print request")
+  recv_ack(con)
+end
+
+-- sends control file
+-- 6.2 02 - Receive control file
+--
+--       +----+-------+----+------+----+
+--       | 02 | Count | SP | Name | LF |
+--       +----+-------+----+------+----+
+--       Command code - 2
+--       Operand 1 - Number of bytes in control file
+--       Operand 2 - Name of control file
+--
+--    The control file must be an ASCII stream with the ends of lines
+--    indicated by ASCII LF.  The total number of bytes in the stream is
+--    sent as the first operand.  The name of the control file is sent as
+--    the second.  It should start with ASCII "cfA", followed by a three
+--    digit job number, followed by the host name which has constructed the
+--    control file.  Acknowledgement processing must occur as usual after
+--    the command is sent.
+--
+--    The next "Operand 1" octets over the same TCP connection are the
+--    intended contents of the control file.  Once all of the contents have
+--    been delivered, an octet of zero bits is sent as an indication that
+--    the file being sent is complete.  A second level of acknowledgement
+--    processing must occur at this point.
+
+-- sends data file
+-- 6.3 03 - Receive data file
+--
+--       +----+-------+----+------+----+
+--       | 03 | Count | SP | Name | LF |
+--       +----+-------+----+------+----+
+--       Command code - 3
+--       Operand 1 - Number of bytes in data file
+--       Operand 2 - Name of data file
+--
+--    The data file may contain any 8 bit values at all.  The total number
+--    of bytes in the stream may be sent as the first operand, otherwise
+--    the field should be cleared to 0.  The name of the data file should
+--    start with ASCII "dfA".  This should be followed by a three digit job
+--    number.  The job number should be followed by the host name which has
+--    constructed the data file.  Interpretation of the contents of the
+--    data file is determined by the contents of the corresponding control
+--    file.  If a data file length has been specified, the next "Operand 1"
+--    octets over the same TCP connection are the intended contents of the
+--    data file.  In this case, once all of the contents have been
+--    delivered, an octet of zero bits is sent as an indication that the
+--    file being sent is complete.  A second level of acknowledgement
+--    processing must occur at this point.
+
+
+local function send_hdr(con, control)
+  local sent = con.skt:send(control)
+  con.try(sent and sent >= 1 , "failed to send header file")
+  recv_ack(con)
+end
+
+local function send_control(con, control)
+  local sent = con.skt:send(control)
+  con.try(sent and sent >= 1, "failed to send control file")
+  send_ack(con)
+end
+
+local function send_data(con,fh,size)
+  local buf
+  while size > 0 do
+    buf,message = fh:read(8192)
+    if buf then
+      st = con.try(con.skt:send(buf))
+      size = size - st
+    else
+      con.try(size == 0, "file size mismatch")
+    end
+  end
+  recv_ack(con) -- note the double acknowledgement
+  send_ack(con)
+  recv_ack(con)
+  return size
+end
+
+
+--[[
+local control_dflt = {
+  "H"..string.sub(socket.hostname,1,31).."\10",        -- host
+  "C"..string.sub(socket.hostname,1,31).."\10",        -- class
+  "J"..string.sub(filename,1,99).."\10",               -- jobname
+  "L"..string.sub(user,1,31).."\10",                   -- print banner page
+  "I"..tonumber(indent).."\10",                        -- indent column count ('f' only)
+  "M"..string.sub(mail,1,128).."\10",                  -- mail when printed user@host
+  "N"..string.sub(filename,1,131).."\10",              -- name of source file
+  "P"..string.sub(user,1,31).."\10",                   -- user name
+  "T"..string.sub(title,1,79).."\10",                  -- title for banner ('p' only)
+  "W"..tonumber(width or 132).."\10",                  -- width of print f,l,p only
+
+  "f"..file.."\10",                                    -- formatted print (remove control chars)
+  "l"..file.."\10",                                    -- print
+  "o"..file.."\10",                                    -- postscript
+  "p"..file.."\10",                                    -- pr format - requires T, L
+  "r"..file.."\10",                                    -- fortran format
+  "U"..file.."\10",                                    -- Unlink (data file only)
+}
+]]
+
+-- generate a varying job number
+local seq = 0
+local function newjob(connection)
+    seq = seq + 1
+    return math.floor(socket.gettime() * 1000 + seq)%1000
+end
+
+
+local format_codes = {
+  binary = 'l',
+  text = 'f',
+  ps = 'o',
+  pr = 'p',
+  fortran = 'r',
+  l = 'l',
+  r = 'r',
+  o = 'o',
+  p = 'p',
+  f = 'f'
+}
+
+-- lp.send{option}
+-- requires option.file
+
+send = socket.protect(function(option)
+  socket.try(option and base.type(option) == "table", "invalid options")
+  local file = option.file
+  socket.try(file, "invalid file name")
+  local fh = socket.try(io.open(file,"rb"))
+  local datafile_size = fh:seek("end") -- get total size
+  fh:seek("set")                       -- go back to start of file
+  local localhost = socket.dns.gethostname() or os.getenv("COMPUTERNAME")
+    or "localhost"
+  local con = connect(localhost, option)
+-- format the control file
+  local jobno = newjob()
+  local localip = socket.dns.toip(localhost)
+  localhost = string.sub(localhost,1,31)
+  local user = string.sub(option.user or os.getenv("LPRUSER") or
+    os.getenv("USERNAME") or os.getenv("USER") or "anonymous", 1,31)
+  local lpfile = string.format("dfA%3.3d%-s", jobno, localhost);
+  local fmt = format_codes[option.format] or 'l'
+  local class = string.sub(option.class or localip or localhost,1,31)
+  local _,_,ctlfn = string.find(file,".*[%/%\\](.*)")
+  ctlfn = string.sub(ctlfn  or file,1,131)
+	local cfile =
+	  string.format("H%-s\nC%-s\nJ%-s\nP%-s\n%.1s%-s\nU%-s\nN%-s\n",
+	  localhost,
+    class,
+	  option.job or "LuaSocket",
+    user,
+    fmt, lpfile,
+    lpfile,
+    ctlfn); -- mandatory part of ctl file
+  if (option.banner) then cfile = cfile .. 'L'..user..'\10' end
+  if (option.indent) then cfile = cfile .. 'I'..base.tonumber(option.indent)..'\10' end
+  if (option.mail) then cfile = cfile .. 'M'..string.sub((option.mail),1,128)..'\10' end
+  if (fmt == 'p' and option.title) then cfile = cfile .. 'T'..string.sub((option.title),1,79)..'\10' end
+  if ((fmt == 'p' or fmt == 'l' or fmt == 'f') and option.width) then
+    cfile = cfile .. 'W'..base.tonumber(option,width)..'\10'
+  end
+
+  con.skt:settimeout(option.timeout or 65)
+-- send the queue header
+  send_queue(con, option.queue)
+-- send the control file header
+  local cfilecmd = string.format("\2%d cfA%3.3d%-s\n",string.len(cfile), jobno, localhost);
+  send_hdr(con,cfilecmd)
+
+-- send the control file
+  send_control(con,cfile)
+
+-- send the data file header
+  local dfilecmd = string.format("\3%d dfA%3.3d%-s\n",datafile_size, jobno, localhost);
+  send_hdr(con,dfilecmd)
+
+-- send the data file
+  send_data(con,fh,datafile_size)
+  fh:close()
+  con.skt:close();
+  return jobno, datafile_size
+end)
+
+--
+-- lp.query({host=,queue=printer|'*', format='l'|'s', list=})
+--
+query = socket.protect(function(p)
+  p = p or {}
+  local localhost = socket.dns.gethostname() or os.getenv("COMPUTERNAME")
+    or "localhost"
+  local con = connect(localhost,p)
+  local fmt
+  if string.sub(p.format or 's',1,1) == 's' then fmt = 3 else fmt = 4 end
+  con.try(con.skt:send(string.format("%c%s %s\n", fmt, p.queue or "*",
+    p.list or "")))
+  local data = con.try(con.skt:receive("*a"))
+  con.skt:close()
+  return data
+end)