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diff --git a/src/ftp.lua b/src/ftp.lua
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+-----------------------------------------------------------------------------
+-- Simple FTP support for the Lua language using the LuaSocket toolkit.
+-- Author: Diego Nehab
+-- Date: 26/12/2000
+-- Conforming to: RFC 959
+-----------------------------------------------------------------------------
+
+-----------------------------------------------------------------------------
+-- Program constants
+-----------------------------------------------------------------------------
+-- timeout in seconds before the program gives up on a connection
+local TIMEOUT = 60
+-- default port for ftp service
+local PORT = 21
+-- this is the default anonymous password. used when no password is
+-- provided in url. should be changed for your e-mail.
+local EMAIL = "anonymous@anonymous.org"
+
+-----------------------------------------------------------------------------
+-- Parses a url and returns its scheme, user, password, host, port 
+-- and path components, according to RFC 1738, Uniform Resource Locators (URL),
+-- of December 1994
+-- Input
+--   url: unique resource locator desired
+--   default: table containing default values to be returned
+-- Returns
+--   table with the following fields:
+--     host: host to connect
+--     path: url path
+--     port: host port to connect
+--     user: user name
+--     pass: password
+--     scheme: protocol
+-----------------------------------------------------------------------------
+local split_url = function(url, default)
+        -- initialize default parameters
+        local parsed = default or {}
+        -- get scheme
+    url = gsub(url, "^(.+)://", function (s) %parsed.scheme = s end)
+        -- get user name and password. both can be empty!
+        -- moreover, password can be ommited
+    url = gsub(url, "^([^@:/]*)(:?)([^:@/]-)@", function (u, c, p) 
+                %parsed.user = u 
+                -- there can be an empty password, but the ':' has to be there
+                -- or else there is no password
+                %parsed.pass = nil -- kill default password
+                if c == ":" then %parsed.pass = p end
+        end)
+        -- get host
+    url = gsub(url, "^([%w%.%-]+)", function (h) %parsed.host = h end)
+        -- get port if any
+    url = gsub(url, "^:(%d+)", function (p) %parsed.port = p end)
+        -- whatever is left is the path
+        if url ~= "" then parsed.path = url end
+        return parsed
+end
+
+-----------------------------------------------------------------------------
+-- Gets ip and port for data connection from PASV answer
+-- Input
+--   pasv: PASV command answer
+-- Returns
+--   ip: string containing ip for data connection
+--   port: port for data connection
+-----------------------------------------------------------------------------
+local get_pasv = function(pasv)
+        local a,b,c,d,p1,p2
+        local ip, port
+        _,_, a, b, c, d, p1, p2 =
+                strfind(pasv, "(%d*),(%d*),(%d*),(%d*),(%d*),(%d*)")
+        if not a or not b or not c or not d or not p1 or not p2 then
+                return nil, nil
+        end
+        ip = format("%d.%d.%d.%d", a, b, c, d)
+        port = tonumber(p1)*256 + tonumber(p2)
+        return ip, port
+end
+
+-----------------------------------------------------------------------------
+-- Sends a FTP command through socket
+-- Input
+--   control: control connection socket
+--   cmd: command
+--   arg: command argument if any
+-----------------------------------------------------------------------------
+local send_command = function(control, cmd, arg)
+        local line, err
+        if arg then line = cmd .. " " .. arg .. "\r\n" 
+        else line = cmd .. "\r\n" end
+        err = control:send(line)
+        return err
+end
+
+-----------------------------------------------------------------------------
+-- Gets FTP command answer, unfolding if neccessary
+-- Input
+--   control: control connection socket
+-- Returns
+--   answer: whole server reply, nil if error
+--   code: answer status code or error message
+-----------------------------------------------------------------------------
+local get_answer = function(control)
+        local code, lastcode, sep
+        local line, err = control:receive()
+        local answer = line
+        if err then return nil, err end
+        _,_, code, sep = strfind(line, "^(%d%d%d)(.)")
+        if not code or not sep then return nil, answer end
+        if sep == "-" then -- answer is multiline
+                repeat 
+                        line, err = control:receive()
+                        if err then return nil, err end
+                        _,_, lastcode, sep = strfind(line, "^(%d%d%d)(.)")
+                        answer = answer .. "\n" .. line
+                until code == lastcode and sep == " " -- answer ends with same code
+        end
+        return answer, tonumber(code)
+end
+
+-----------------------------------------------------------------------------
+-- Checks if a message return is correct. Closes control connection if not.
+-- Input
+--   control: control connection socket
+--   success: table with successfull reply status code
+-- Returns
+--   code: reply code or nil in case of error
+--   answer: server complete answer or system error message
+-----------------------------------------------------------------------------
+local check_answer = function(control, success)
+        local answer, code = %get_answer(control)
+        if not answer then 
+                control:close()
+                return nil, code
+        end
+        if type(success) ~= "table" then success = {success} end
+        for i = 1, getn(success) do
+                if code == success[i] then
+                        return code, answer
+                end
+        end
+        control:close()
+        return nil, answer
+end
+
+-----------------------------------------------------------------------------
+-- Trys a command on control socked, in case of error, the control connection 
+-- is closed.
+-- Input
+--   control: control connection socket
+--   cmd: command
+--   arg: command argument or nil if no argument
+--   success: table with successfull reply status code
+-- Returns
+--   code: reply code or nil in case of error
+--   answer: server complete answer or system error message
+-----------------------------------------------------------------------------
+local try_command = function(control, cmd, arg, success)
+        local err = %send_command(control, cmd, arg)
+        if err then 
+                control:close()
+                return nil, err
+        end
+        local code, answer = %check_answer(control, success)
+        if not code then return nil, answer end
+        return code, answer
+end
+
+-----------------------------------------------------------------------------
+-- Creates a table with all directories in path
+-- Input
+--   file: abolute path to file
+-- Returns
+--   file: filename
+--   path: table with directories to reach filename
+--   isdir: is it a directory or a file
+-----------------------------------------------------------------------------
+local split_path  = function(file)
+        local path = {}
+        local isdir
+        file = file or "/"
+        -- directory ends with a '/'
+        _,_, isdir = strfind(file, "([/])$")
+        gsub(file, "([^/]+)", function (dir) tinsert(%path, dir) end)
+        if not isdir then file = tremove(path)
+        else file = nil end
+        return file, path, isdir
+end
+
+-----------------------------------------------------------------------------
+-- Check server greeting
+-- Input
+--   control: control connection with server
+-- Returns
+--   code: nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local check_greeting = function(control)
+        local code, answer = %check_answer(control, {120, 220})
+        if not code then return nil, answer end
+        if code == 120 then -- please try again, somewhat busy now...
+                code, answer = %check_answer(control, {220})
+        end
+        return code, answer
+end
+
+-----------------------------------------------------------------------------
+-- Log in on server
+-- Input
+--   control: control connection with server
+--   user: user name
+--   pass: user password if any
+-- Returns
+--   code: nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local login = function(control, user, pass)
+        local code, answer = %try_command(control, "user", parsed.user, {230, 331})
+        if not code then return nil, answer end
+        if code == 331 and parsed.pass then -- need pass and we have pass
+                code, answer = %try_command(control, "pass", parsed.pass, {230, 202})
+        end
+        return code, answer
+end
+
+-----------------------------------------------------------------------------
+-- Change to target directory
+-- Input
+--   control: socket for control connection with server
+--   path: array with directories in order
+-- Returns
+--   code: nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local cwd = function(control, path)
+        local code, answer = 250, "Home directory used"
+        for i = 1, getn(path) do
+                code, answer = %try_command(control, "cwd", path[i], {250})
+                if not code then return nil, answer end
+        end
+        return code, answer
+end
+
+-----------------------------------------------------------------------------
+-- Start data connection with server
+-- Input
+--   control: control connection with server
+-- Returns
+--   data: socket for data connection with server, nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local start_dataconnection = function(control)
+        -- ask for passive data connection
+        local code, answer = %try_command(control, "pasv", nil, {227})
+        if not code then return nil, answer end
+        -- get data connection parameters from server reply
+        local host, port = %get_pasv(answer)
+        if not host or not port then return nil, answer end
+        -- start data connection with given parameters
+        local data, err = connect(host, port)
+        if not data then return nil, err end
+        data:timeout(%TIMEOUT)
+        return data
+end
+
+-----------------------------------------------------------------------------
+-- Closes control connection with server
+-- Input
+--   control: control connection with server
+-- Returns
+--   code: nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local logout = function(control)
+        local code, answer = %try_command(control, "quit", nil, {221})
+        if not code then return nil, answer end
+        control:close()
+        return code, answer
+end
+
+-----------------------------------------------------------------------------
+-- Retrieves file or directory listing
+-- Input
+--   control: control connection with server
+--   data: data connection with server
+--   file: file name under current directory
+--   isdir: is file a directory name?
+-- Returns
+--   file: string with file contents, nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local retrieve_file = function(control, data, file, isdir)
+        -- ask server for file or directory listing accordingly
+        if isdir then code, answer = %try_command(control, "nlst", file, {150, 125})
+        else code, answer = %try_command(control, "retr", file, {150, 125}) end
+        if not code then 
+                control:close()
+                data:close()
+                return nil, answer 
+        end
+        -- download whole file
+        file, err = data:receive("*a")
+        data:close()
+        if err then 
+                control:close()
+                return nil, err
+        end
+        -- make sure file transfered ok
+        code, answer = %check_answer(control, {226, 250})
+        if not code then return nil, answer 
+        else return file, answer end
+end
+
+-----------------------------------------------------------------------------
+-- Stores a file
+-- Input
+--   control: control connection with server
+--   data: data connection with server
+--   file: file name under current directory
+--   bytes: file contents in string 
+-- Returns
+--   file: string with file contents, nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local store_file = function (control, data, file, bytes)
+        local code, answer = %try_command(control, "stor", file, {150, 125})
+        if not code then 
+                data:close()
+                return nil, answer 
+        end
+        -- send whole file and close connection to mark file end
+        answer = data:send(bytes)
+        data:close()
+        if answer then 
+                control:close()
+                return nil, answer
+        end
+        -- check if file was received right
+        return %check_answer(control, {226, 250})
+end
+
+-----------------------------------------------------------------------------
+-- Change transfer type
+-- Input
+--   control: control connection with server
+--   type: new transfer type
+-- Returns
+--   code: nil if error
+--   answer: server answer or error message
+-----------------------------------------------------------------------------
+local change_type = function(control, type)
+        if type == "b" then type = "i" else type = "a" end
+        return %try_command(control, "type", type, {200})
+end
+
+-----------------------------------------------------------------------------
+-- Retrieve a file from a ftp server
+-- Input
+--   url: file location
+--   type: "binary" or "ascii"
+-- Returns
+--   file: downloaded file or nil in case of error
+--   err: error message if any
+-----------------------------------------------------------------------------
+function ftp_get(url, type)
+        local control, data, err
+        local answer, code, server, file, path
+        parsed = %split_url(url, {user = "anonymous", port = 21, pass = %EMAIL})
+        -- start control connection
+        control, err = connect(parsed.host, parsed.port)
+        if not control then return nil, err end
+        control:timeout(%TIMEOUT)
+        -- get and check greeting
+        code, answer = %check_greeting(control)
+        if not code then return nil, answer end
+        -- try to log in
+        code, answer = %login(control, parsed.user, parsed.pass)
+        if not code then return nil, answer end
+        -- go to directory
+        file, path, isdir = %split_path(parsed.path)
+        code, answer = %cwd(control, path)
+        if not code then return nil, answer end
+        -- change to binary type?
+        code, answer = %change_type(control, type)
+        if not code then return nil, answer end
+        -- start data connection
+        data, answer = %start_dataconnection(control)
+        if not data then return nil, answer end
+        -- ask server to send file or directory listing
+        file, answer = %retrieve_file(control, data, file, isdir)
+        if not file then return nil, answer end
+        -- disconnect
+        %logout(control)
+        -- return whatever file we received plus a possible error
+        return file, answer
+end
+
+-----------------------------------------------------------------------------
+-- Uploads a file to a FTP server
+-- Input
+--   url: file location
+--   bytes: file contents
+--   type: "binary" or "ascii"
+-- Returns
+--   err: error message if any
+-----------------------------------------------------------------------------
+function ftp_put(url, bytes, type)
+        local control, data
+        local answer, code, server, file, path
+        parsed = %split_url(url, {user = "anonymous", port = 21, pass = %EMAIL})
+        -- start control connection
+        control, answer = connect(parsed.host, parsed.port)
+        if not control then return answer end
+        control:timeout(%TIMEOUT)
+        -- get and check greeting
+        code, answer = %check_greeting(control)
+        if not code then return answer end
+        -- try to log in
+        code, answer = %login(control, parsed.user, parsed.pass)
+        if not code then return answer end
+        -- go to directory
+        file, path, isdir = %split_path(parsed.path)
+        code, answer = %cwd(control, path)
+        if not code then return answer end
+        -- change to binary type?
+        code, answer = %change_type(control, type)
+        if not code then return answer end
+        -- start data connection
+        data, answer = %start_dataconnection(control)
+        if not data then return answer end
+        -- ask server to send file or directory listing
+        code, answer = %store_file(control, data, file, bytes)
+        if not code then return answer end
+        -- disconnect
+        %logout(control)
+        -- return whatever file we received plus a possible error
+        return nil
+end