Updated for LuaSocket 1.4.

Better tested, some name changes.

1 files changed, 324 insertions, 227 deletions

diff --git a/src/ftp.lua b/src/ftp.lua
index bbb672b..98b08eb 100644
--- a/src/ftp.lua
+++ b/src/ftp.lua
@@ -1,60 +1,62 @@
 -----------------------------------------------------------------------------
--- Simple FTP support for the Lua language using the LuaSocket 1.3b toolkit.
+-- FTP support for the Lua language
+-- LuaSocket 1.4 toolkit.
 -- Author: Diego Nehab
 -- Date: 26/12/2000
--- Conforming to: RFC 959
+-- Conforming to: RFC 959, LTN7
+-- RCS ID: $Id$
 -----------------------------------------------------------------------------
 
+local Public, Private = {}, {}
+FTP = Public
+
 -----------------------------------------------------------------------------
 -- Program constants
 -----------------------------------------------------------------------------
 -- timeout in seconds before the program gives up on a connection
-local TIMEOUT = 60
+Public.TIMEOUT = 60
 -- default port for ftp service
-local PORT = 21
+Public.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"
+-- provided in url. should be changed to your e-mail.
+Public.EMAIL = "anonymous@anonymous.org"
 -- block size used in transfers
-local BLOCKSIZE = 4096
+Public.BLOCKSIZE = 8192
+
+-----------------------------------------------------------------------------
+-- Required libraries
+-----------------------------------------------------------------------------
+dofile "concat.lua"
+dofile "url.lua"
+dofile "code.lua"
 
 -----------------------------------------------------------------------------
--- 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
+-- Tries to send DOS mode lines. Closes socket on error.
 -- Input
---   url: unique resource locator desired
---   default: table containing default values to be returned
+--   sock: server socket
+--   line: string to be sent
 -- 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
+--   err: message in case of error, nil if successfull
+-----------------------------------------------------------------------------
+function Private.try_sendline(sock, line)
+    local err = sock:send(line .. "\r\n")
+    if err then sock:close() end
+    return err
+end
+
+-----------------------------------------------------------------------------
+-- Tries to get a pattern from the server and closes socket on error
+--   sock: socket connected to the server
+--   ...: pattern to receive
+-- Returns
+--   ...: received pattern
+--   err: error message if any
+-----------------------------------------------------------------------------
+function Private.try_receive(...)
+    local sock = arg[1]
+    local data, err = call(sock.receive, arg)
+    if err then sock:close() end
+    return data, err
 end
 
 -----------------------------------------------------------------------------
@@ -65,14 +67,12 @@ end
 --   ip: string containing ip for data connection
 --   port: port for data connection
 -----------------------------------------------------------------------------
-local get_pasv = function(pasv)
-        local a,b,c,d,p1,p2
+function Private.get_pasv(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 and b and c and d and p1 and p2) then
-                return nil, nil
-        end
+        if not (a and b and c and d and p1 and 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
@@ -87,12 +87,11 @@ end
 -- Returns
 --   error message in case of error, nil otherwise
 -----------------------------------------------------------------------------
-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
+function Private.send_command(control, cmd, arg)
+        local line
+        if arg then line = cmd .. " " .. arg
+        else line = cmd end
+        return %Private.try_sendline(control, line)
 end
 
 -----------------------------------------------------------------------------
@@ -103,16 +102,16 @@ end
 --   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()
+function Private.get_answer(control)
+        local code, lastcode, sep, _
+        local line, err = %Private.try_receive(control)
         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()
+                        line, err = %Private.try_receive(control)
                         if err then return nil, err end
                         _,_, lastcode, sep = strfind(line, "^(%d%d%d)(.)")
                         answer = answer .. "\n" .. line
@@ -130,12 +129,9 @@ end
 --   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
+function Private.check_answer(control, success)
+        local answer, code = %Private.get_answer(control)
+        if not answer then return nil, code end
         if type(success) ~= "table" then success = {success} end
         for i = 1, getn(success) do
                 if code == success[i] then
@@ -158,38 +154,10 @@ end
 --   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
---   a table with the following fields
---     name: filename
---     path: directory to file
---     isdir: is it a directory?
------------------------------------------------------------------------------
-local split_path  = function(file)
-    local parsed = {}
-    file = gsub(file, "(/)$", function(i) %parsed.isdir = i end)
-    if not parsed.isdir then
-        file = gsub(file, "([^/]+)$", function(n) %parsed.name = n end)
-    end
-    file = gsub(file, "/$", "")
-    file = gsub(file, "^/", "")
-    if file == "" then file = nil end
-    parsed.path = file
-    if parsed.path or parsed.name or parsed.isdir then return parsed end
+function Private.command(control, cmd, arg, success)
+        local err = %Private.send_command(control, cmd, arg)
+        if err then return nil, err end
+        return %Private.check_answer(control, success)
 end
 
 -----------------------------------------------------------------------------
@@ -200,11 +168,10 @@ end
 --   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
+function Private.greet(control)
+        local code, answer = %Private.check_answer(control, {120, 220})
         if code == 120 then -- please try again, somewhat busy now...
-                code, answer = %check_answer(control, {220})
+                return %Private.check_answer(control, {220})
         end
         return code, answer
 end
@@ -214,16 +181,15 @@ end
 -- Input
 --   control: control connection with server
 --   user: user name
---   pass: user password if any
+--   password: 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})
+function Private.login(control, user, password)
+        local code, answer = %Private.command(control, "user", user, {230, 331})
+        if code == 331 and password then -- need pass and we have pass
+                return %Private.command(control, "pass", password, {230, 202})
         end
         return code, answer
 end
@@ -237,12 +203,9 @@ end
 --   code: nil if error
 --   answer: server answer or error message
 -----------------------------------------------------------------------------
-local cwd = function(control, path)
-        local code, answer = 250, "Home directory used"
-        if path then
-                code, answer = %try_command(control, "cwd", path, {250})
-        end
-        return code, answer
+function Private.cwd(control, path)
+        if path then return %Private.command(control, "cwd", path, {250}) 
+        else return 250, nil end
 end
 
 -----------------------------------------------------------------------------
@@ -253,20 +216,19 @@ end
 --   server: server socket bound to local address, nil if error
 --   answer: error message if any
 -----------------------------------------------------------------------------
-local port = function(control)
+function Private.port(control)
         local code, answer
         local server, ctl_ip
         ctl_ip, answer = control:getsockname()
         server, answer = bind(ctl_ip, 0)
-        server:timeout(%TIMEOUT)
+        server:timeout(%Public.TIMEOUT)
         local ip, p, ph, pl
         ip, p = server:getsockname()
         pl = mod(p, 256)
         ph = (p - pl)/256
     local arg = gsub(format("%s,%d,%d", ip, ph, pl), "%.", ",")
-        code, answer = %try_command(control, "port", arg, {200})
+        code, answer = %Private.command(control, "port", arg, {200})
         if not code then 
-                control:close()
                 server:close()
                 return nil, answer
         else return server end
@@ -280,10 +242,9 @@ end
 --   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()
+function Private.logout(control)
+        local code, answer = %Private.command(control, "quit", nil, {221})
+        if code then control:close() end
         return code, answer
 end
 
@@ -295,10 +256,10 @@ end
 -- Returns
 --   nil if successfull, or an error message in case of error
 -----------------------------------------------------------------------------
-local receive_indirect = function(data, callback)
+function Private.receive_indirect(data, callback)
         local chunk, err, res
         while not err do
-                chunk, err = data:receive(%BLOCKSIZE)
+                chunk, err = %Private.try_receive(data, %Public.BLOCKSIZE)
                 if err == "closed" then err = "done" end
                 res = callback(chunk, err)
                 if not res then break end
@@ -310,33 +271,38 @@ end
 -- Input
 --   control: control connection with server
 --   server: server socket bound to local address
---   file: file name under current directory
---   isdir: is file a directory name?
---   callback: callback to receive file contents
+--   name: file name 
+--   is_directory: is file a directory name?
+--   download_cb: callback to receive file contents
 -- Returns
 --   err: error message in case of error, nil otherwise
 -----------------------------------------------------------------------------
-local retrieve = function(control, server, file, isdir, callback)
+function Private.retrieve(control, server, name, is_directory, download_cb)
         local code, answer
         local data
         -- 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 is_directory then 
+                code, answer = %Private.cwd(control, name) 
+                if not code then return answer end
+                code, answer = %Private.command(control, "nlst", nil, {150, 125})
+        else 
+                code, answer = %Private.command(control, "retr", name, {150, 125}) 
+        end
+        if not code then return nil, answer end
         data, answer = server:accept()
         server:close()
         if not data then 
                 control:close()
                 return answer 
         end
-        answer = %receive_indirect(data, callback)
+        answer = %Private.receive_indirect(data, download_cb)
         if answer then 
                 control:close()
                 return answer
         end
         data:close()
         -- make sure file transfered ok
-        code, answer = %check_answer(control, {226, 250})
-        if not code then return answer end
+        return %Private.check_answer(control, {226, 250})
 end
 
 -----------------------------------------------------------------------------
@@ -344,11 +310,11 @@ end
 -- Input
 --   data: data connection
 --   send_cb: callback to produce file contents
---   chunk, size: first callback results
+--   chunk, size: first callback return values
 -- Returns
 --   nil if successfull, or an error message in case of error
 -----------------------------------------------------------------------------
-local try_sendindirect = function(data, send_cb, chunk, size)
+function Private.send_indirect(data, send_cb, chunk, size)
     local sent, err
     sent = 0
     while 1 do
@@ -358,9 +324,9 @@ local try_sendindirect = function(data, send_cb, chunk, size)
             else return "invalid callback return" end
         end
         err = data:send(chunk)
-        if err then 
-            data:close() 
-            return err 
+        if err then
+            data:close()
+            return err
         end
         sent = sent + strlen(chunk)
         if sent >= size then break end
@@ -379,9 +345,9 @@ end
 --   code: return code, nil if error
 --   answer: server answer or error message
 -----------------------------------------------------------------------------
-local store = function(control, server, file, send_cb)
-        local data
-        local code, answer = %try_command(control, "stor", file, {150, 125})
+function Private.store(control, server, file, send_cb)
+        local data, err
+        local code, answer = %Private.command(control, "stor", file, {150, 125})
         if not code then 
                 control:close()
                 return nil, answer 
@@ -394,7 +360,7 @@ local store = function(control, server, file, send_cb)
                 return nil, answer 
         end
         -- send whole file 
-        err = %try_sendindirect(data, send_cb, send_cb())
+        err = %Private.send_indirect(data, send_cb, send_cb())
         if err then 
                 control:close()
                 return nil, err
@@ -402,144 +368,275 @@ local store = function(control, server, file, send_cb)
         -- close connection to inform that file transmission is complete
         data:close()
         -- check if file was received correctly
-        return %check_answer(control, {226, 250})
+        return %Private.check_answer(control, {226, 250})
 end
 
 -----------------------------------------------------------------------------
 -- Change transfer type
 -- Input
 --   control: control connection with server
---   type: new transfer type
+--   params: "type=i" for binary or "type=a" for ascii
 -- Returns
---   code: nil if error
---   answer: server answer or error message
+--   err: error message if any
 -----------------------------------------------------------------------------
-local change_type = function(control, type)
-        if type == "b" then type = "i" else type = "a" end
-        return %try_command(control, "type", type, {200})
+function Private.change_type(control, params)
+        local type
+        if params == "type=i" then type = "i" 
+        elseif params == "type=a" then type = "a" end
+        if type then 
+                local code, err = %Private.command(control, "type", type, {200})
+                if not code then return err end
+        end
 end
 
 -----------------------------------------------------------------------------
--- Retrieve a file from a ftp server
+-- Starts a control connection, checks the greeting and log on
 -- Input
---   url: file location
---   receive_cb: callback to receive file contents
---   type: "binary" or "ascii"
+--   parsed: parsed URL components
 -- Returns
+--   control: control connection with server, or nil if error
 --   err: error message if any
 -----------------------------------------------------------------------------
-function ftp_getindirect(url, receive_cb, type)
-        local control, server, data, err
-        local answer, code, server, pfile, file
-        parsed = %split_url(url, {user = "anonymous", port = 21, pass = %EMAIL})
+function Private.open(parsed)
         -- start control connection
-        control, err = connect(parsed.host, parsed.port)
-        if not control then return err end
-        control:timeout(%TIMEOUT)
-        -- get and check greeting
-        code, answer = %check_greeting(control)
-        if not code then return answer end
+        local control, err = connect(parsed.host, parsed.port)
+        if not control then return nil, err end
+        -- make sure we don't block forever
+        control:timeout(%Public.TIMEOUT)
+        -- check greeting
+        local code, answer = %Private.greet(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 answer end
-        -- go to directory
-        pfile = %split_path(parsed.path)
-        if not pfile then return "invalid path" end
-        code, answer = %cwd(control, pfile.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
-        -- setup passive connection
-        server, answer = %port(control)
-        if not server then return answer end
-        -- ask server to send file or directory listing
-        err = %retrieve(control, server, pfile.name, pfile.isdir, receive_cb)
-        if err then return err end
+        code, err = %Private.login(control, parsed.user, parsed.password)
+        if not code then return nil, err
+        else return control end
+end
+
+-----------------------------------------------------------------------------
+-- Closes the connection with the server
+-- Input
+--   control: control connection with server
+-----------------------------------------------------------------------------
+function Private.close(control)
         -- disconnect
-        %logout(control)
+        %Private.logout(control)
 end
 
 -----------------------------------------------------------------------------
--- Uploads a file to a FTP server
+-- Changes to the directory pointed to by URL
 -- Input
---   url: file location
---   send_cb: callback to produce the file contents
---   type: "binary" or "ascii"
+--   control: control connection with server
+--   segment: parsed URL path segments
 -- Returns
 --   err: error message if any
 -----------------------------------------------------------------------------
-function ftp_putindirect(url, send_cb, type)
-        local control, data
-        local answer, code, server, file, pfile
-        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
-        pfile = %split_path(parsed.path)
-        if not pfile or pfile.isdir then return "invalid path" end
-        code, answer = %cwd(control, pfile.path)
-        if not code then return answer end
-        -- change to binary type?
-        code, answer = %change_type(control, type)
+function Private.change_dir(control, segment)
+        local n = getn(segment)
+        for i = 1, n-1 do
+                local code, answer = %Private.cwd(control, segment[i])
+                if not code then return answer end
+        end
+end
+
+-----------------------------------------------------------------------------
+-- Stores a file in current directory
+-- Input
+--   control: control connection with server
+--   request: a table with the fields:
+--     upload_cb: send callback to send file contents
+--   segment: parsed URL path segments
+-- Returns
+--   err: error message if any
+-----------------------------------------------------------------------------
+function Private.upload(control, request, segment)
+        local code, name, upload_cb
+        -- get remote file name
+        name = segment[getn(segment)]
+        if not name then 
+                control:close()
+                return "Invalid file path" 
+        end
+        upload_cb = request.upload_cb
+        -- setup passive connection
+        local server, answer = %Private.port(control)
+        if not server then return answer end
+        -- ask server to receive file
+        code, answer = %Private.store(control, server, name, upload_cb)
         if not code then return answer end
+end
+
+-----------------------------------------------------------------------------
+-- Download a file from current directory
+-- Input
+--   control: control connection with server
+--   request: a table with the fields:
+--     download_cb: receive callback to receive file contents
+--   segment: parsed URL path segments
+-- Returns
+--   err: error message if any
+-----------------------------------------------------------------------------
+function Private.download(control, request, segment)
+        local code, name, is_directory, download_cb
+        is_directory = segment.is_directory
+        download_cb = request.download_cb
+        -- get remote file name
+        name = segment[getn(segment)]
+        if not name and not is_directory then 
+                control:close()
+                return "Invalid file path" 
+        end
         -- setup passive connection
-        server, answer = %port(control)
+        local server, answer = %Private.port(control)
         if not server then return answer end
-        -- ask server to send file
-        code, answer = %store(control, server, pfile.name, send_cb)
+        -- ask server to send file or directory listing
+        code, answer = %Private.retrieve(control, server, name, 
+                is_directory, download_cb)
         if not code then return answer end
-        -- disconnect
-        %logout(control)
-        -- no errors
-        return nil
+end
+
+-----------------------------------------------------------------------------
+-- Parses the FTP URL setting default values
+-- Input
+--   request: a table with the fields:
+--     url: the target URL
+--     type: "i" for "image" mode, "a" for "ascii" mode or "d" for directory
+--     user: account user name
+--     password: account password
+-- Returns
+--   parsed: a table with parsed components
+-----------------------------------------------------------------------------
+function Private.parse_url(request)
+        local parsed = URL.parse_url(request.url, {
+                host = "",
+                user = "anonymous", 
+                port = 21, 
+                path = "/",
+                password = %Public.EMAIL
+        })
+        -- explicit login information overrides that given by URL
+        parsed.user = request.user or parsed.user
+        parsed.password = request.password or parsed.password
+        -- explicit representation type overrides that given by URL
+        if request.type then parsed.params = "type=" .. request.type end
+        return parsed
+end
+
+-----------------------------------------------------------------------------
+-- Parses the FTP URL path setting default values
+-- Input
+--   parsed: a table with the parsed URL components
+-- Returns
+--   dirs: a table with parsed directory components
+-----------------------------------------------------------------------------
+function Private.parse_path(parsed)
+        local segment = URL.parse_path(parsed.path)
+        segment.is_directory = segment.is_directory or (parsed.params == "type=d")
+        return segment
+end
+
+-----------------------------------------------------------------------------
+-- Builds a request table from a URL or request table
+-- Input
+--   url_or_request: target url or request table (a table with the fields:
+--     url: the target URL
+--     type: "i" for "image" mode, "a" for "ascii" mode or "d" for directory
+--     user: account user name
+--     password: account password)
+-- Returns
+--   request: request table
+-----------------------------------------------------------------------------
+function Private.build_request(data)
+    local request = {}
+    if type(data) == "table" then for i, v in data do request[i] = v end
+    else request.url = data end
+    return request
+end
+
+-----------------------------------------------------------------------------
+-- Downloads a file from a FTP server
+-- Input
+--   request: a table with the fields:
+--     url: the target URL
+--     type: "i" for "image" mode, "a" for "ascii" mode or "d" for directory
+--     user: account user name
+--     password: account password
+--     download_cb: receive callback to receive file contents
+-- Returns
+--   err: error message if any
+-----------------------------------------------------------------------------
+function Public.get_cb(request)
+        local parsed = %Private.parse_url(request)
+        local control, err = %Private.open(parsed)
+        if not control then return err end
+        local segment = %Private.parse_path(parsed)
+        return %Private.change_dir(control, segment) or
+                %Private.change_type(control, parsed.params) or
+                %Private.download(control, request, segment) or 
+                %Private.close(control)
 end
 
 -----------------------------------------------------------------------------
 -- Uploads a file to a FTP server
 -- Input
---   url: file location
---   bytes: file contents
---   type: "binary" or "ascii"
+--   request: a table with the fields:
+--     url: the target URL
+--     type: "i" for "image" mode, "a" for "ascii" mode or "d" for directory
+--     user: account user name
+--     password: account password
+--     upload_cb: send callback to send file contents
 -- Returns
 --   err: error message if any
 -----------------------------------------------------------------------------
-function ftp_put(url, bytes, type)
-        local send_cb = function()
-                return %bytes, strlen(%bytes)
-        end
-        return ftp_putindirect(url, send_cb, type)
+function Public.put_cb(request)
+        local parsed = %Private.parse_url(request)
+        local control, err = %Private.open(parsed)
+        if not control then return err end
+        local segment = %Private.parse_path(parsed)
+        return %Private.change_dir(control, segment) or
+                %Private.change_type(control, parsed.params) or
+                %Private.upload(control, request, segment) or 
+                %Private.close(control)
 end
 
 -----------------------------------------------------------------------------
--- We need fast concatenation routines for direct requests
+-- Uploads a file to a FTP server
+-- Input
+--   url_or_request: target url or request table (a table with the fields:
+--     url: the target URL
+--     type: "i" for "image" mode, "a" for "ascii" mode or "d" for directory
+--     user: account user name
+--     password: account password)
+--   content: file contents
+-- Returns
+--   err: error message if any
 -----------------------------------------------------------------------------
-dofile("buffer.lua")
+function Public.put(url_or_request, content)
+        local request = %Private.build_request(url_or_request)
+        request.upload_cb = function()
+                return %content, strlen(%content)
+        end
+        return %Public.put_cb(request)
+end
 
 -----------------------------------------------------------------------------
 -- Retrieve a file from a ftp server
 -- Input
---   url: file location
---   type: "binary" or "ascii"
+--   url_or_request: target url or request table (a table with the fields:
+--     url: the target URL
+--     type: "i" for "image" mode, "a" for "ascii" mode or "d" for directory
+--     user: account user name
+--     password: account password)
 -- Returns
 --   data: file contents as a string
 --   err: error message in case of error, nil otherwise
 -----------------------------------------------------------------------------
-function ftp_get(url, type)
-        local bytes = { buf = buf_create() }
-        local receive_cb = function(chunk, err)
-                if not chunk then %bytes.buf = nil end
-                buf_addstring(%bytes.buf, chunk)
+function Public.get(url_or_request)
+        local cat = Concat.create()
+        local request = %Private.build_request(url_or_request)
+        request.download_cb = function(chunk, err)
+                if chunk then %cat:addstring(chunk) end
                 return 1
         end
-        err = ftp_getindirect(url, receive_cb, type)
-        return buf_getresult(bytes.buf), err
+        local err = %Public.get_cb(request)
+        return cat:getresult(), err
 end