generator/xml.lua

   1 #!/usr/bin/lua
   2
   3 --[[
   4
   5 Copyright (c) 2007-2008 Mauro Iazzi
   6
   7 Permission is hereby granted, free of charge, to any person
   8 obtaining a copy of this software and associated documentation
   9 files (the "Software"), to deal in the Software without
  10 restriction, including without limitation the rights to use,
  11 copy, modify, merge, publish, distribute, sublicense, and/or sell
  12 copies of the Software, and to permit persons to whom the
  13 Software is furnished to do so, subject to the following
  14 conditions:
  15
  16 The above copyright notice and this permission notice shall be
  17 included in all copies or substantial portions of the Software.
  18
  19 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  20 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  21 OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  22 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  23 HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  24 WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  25 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  26 OTHER DEALINGS IN THE SOFTWARE.
  27
  28 --]]
  29
  30
  31 local parseargs, collect
  32
  33 local escapes = {
  34         gt = '>',
  35         lt = '<',
  36 }
  37
  38 local strip_escapes = function (s)
  39         s = string.gsub(s, '&(%a+);', escapes)
  40         s = string.gsub(s, '&amp;', '&')
  41         return s
  42 end
  43
  44
  45 function parseargs(s)
  46         local arg = {}
  47         string.gsub(s, "([%w_]+)=([\"'])(.-)%2", function (w, _, a)
  48                 arg[strip_escapes(w)] = strip_escapes(a)
  49         end)
  50         return arg
  51 end
  52
  53 function collect(s)
  54         local stack = {}
  55         local index = {}
  56         local top = {}
  57         table.insert(stack, top)
  58         local ni,c,label,xarg, empty
  59         local i, j = 1, 1
  60         while true do
  61                 ni,j,c,label,xarg, empty = string.find(s, "<(%/?)(%w+)(.-)(%/?)>", j)
  62                 if not ni then break end
  63                 local text = string.sub(s, i, ni-1)
  64                 if not string.find(text, "^%s*$") then
  65                         table.insert(top, strip_escapes(text))
  66                 end
  67                 if empty == "/" then  -- empty element tag
  68                         table.insert(top, {label=label, xarg=parseargs(xarg), empty=1})
  69                 elseif c == "" then   -- start tag
  70                         top = {label=label, xarg=parseargs(xarg)}
  71                         table.insert(stack, top)   -- new level
  72                 else  -- end tag
  73                         local toclose = table.remove(stack)  -- remove top
  74                         top = stack[#stack]
  75                         if #stack < 1 then
  76                                 error("nothing to close with "..label)
  77                         end
  78                         if toclose.label ~= label then
  79                                 error("trying to close "..toclose.label.." with "..label)
  80                         end
  81                         table.insert(top, toclose)
  82                         toclose.parent = top
  83                         toclose.index = #top
  84                         index[toclose] = true
  85                 end
  86                 i = j+1
  87         end
  88         local text = string.sub(s, i)
  89         if not string.find(text, "^%s*$") then
  90                 table.insert(stack[#stack], text)
  91         end
  92         if #stack > 1 then
  93                 error("unclosed "..stack[stack.n].label)
  94         end
  95         return stack[1], index
  96 end
  97
  98 return collect