libs/nixio/lua/nixio/util.lua

   1 --[[
   2 nixio - Linux I/O library for lua
   3
   4 Copyright 2008 Steven Barth <steven@midlink.org>
   5
   6 Licensed under the Apache License, Version 2.0 (the "License");
   7 you may not use this file except in compliance with the License.
   8 You may obtain a copy of the License at
   9
  10 http://www.apache.org/licenses/LICENSE-2.0
  11
  12 $Id$
  13 ]]--
  14
  15 local table = require "table"
  16 local nixio = require "nixio"
  17 local setmetatable, assert = setmetatable, assert
  18
  19 module "nixio.util"
  20
  21 local BUFFERSIZE = 8096
  22 local socket = nixio.socket_meta
  23
  24 function socket.recvall(self, len)
  25         local block, code, msg = self:recv(len)
  26
  27         if not block then
  28                 return "", code, msg, len
  29         elseif #block == 0 then
  30                 return "", nil, nil, len
  31         end
  32
  33         local data, total = {block}, #block
  34
  35         while len > total do
  36                 block, code, msg = self:recv(len - total)
  37
  38                 if not block then
  39                         return data, code, msg, len - #data
  40                 elseif #block == 0 then
  41                         return data, nil, nil, len - #data
  42                 end
  43
  44                 data[#data+1], total = block, total + #block
  45         end
  46
  47         return (#data > 1 and table.concat(data) or data[1]), nil, nil, 0
  48 end
  49
  50 function socket.sendall(self, data)
  51         local total, block = 0
  52         local sent, code, msg = self:send(data)
  53
  54         if not sent then
  55                 return total, code, msg, data
  56         end
  57
  58         while sent < #data do
  59                 block, total = data:sub(sent + 1), total + sent
  60                 sent, code, msg = self:send(block)
  61
  62                 if not sent then
  63                         return total, code, msg, block
  64                 end
  65         end
  66
  67         return total + sent, nil, nil, ""
  68 end
  69
  70 function socket.linesource(self, limit)
  71         limit = limit or BUFFERSIZE
  72         local buffer = ""
  73         local bpos = 0
  74         return function(flush)
  75                 local line, endp, _
  76
  77                 if flush then
  78                         line = buffer:sub(bpos + 1)
  79                         buffer = ""
  80                         bpos = 0
  81                         return line
  82                 end
  83
  84                 while not line do
  85                         _, endp, line = buffer:find("(.-)\r?\n", bpos + 1)
  86                         if line then
  87                                 bpos = endp
  88                                 return line
  89                         elseif #buffer < limit + bpos then
  90                                 local newblock, code = self:recv(limit + bpos - #buffer)
  91                                 if not newblock then
  92                                         return nil, code
  93                                 elseif #newblock == 0 then
  94                                         return nil
  95                                 end
  96                                 buffer = buffer:sub(bpos + 1) .. newblock
  97                                 bpos = 0
  98                         else
  99                                 return nil, 0
 100                         end
 101                 end
 102         end
 103 end
 104
 105 function socket.blocksource(self, bs, limit)
 106         bs = bs or BUFFERSIZE
 107         return function()
 108                 local toread = bs
 109                 if limit then
 110                         if limit < 1 then
 111                                 return nil
 112                         elseif limit < toread then
 113                                 toread = limit
 114                         end
 115                 end
 116
 117                 local block, code, msg = self:recv(toread)
 118
 119                 if not block then
 120                         return nil, code
 121                 elseif #block == 0 then
 122                         return nil
 123                 else
 124                         if limit then
 125                                 limit = limit - #block
 126                         end
 127
 128                         return block
 129                 end
 130         end
 131 end