xml.lua

   1 #!/usr/bin/lua
   2
   3 local xml_parser = {
   4
   5 strip_escapes = function (self, s)
   6         s = string.gsub(s, '&gt;', '>')
   7         s = string.gsub(s, '&lt;', '<')
   8         return s
   9 end,
  10
  11 parseargs = function (self, s)
  12         local arg = {}
  13         string.gsub(s, "([%w_]+)=([\"'])(.-)%2", function (w, _, a)
  14                 arg[self:strip_escapes(w)] = self:strip_escapes(a)
  15         end)
  16         return arg
  17 end,
  18
  19 collect = function (self, s)
  20         local stack = {}
  21         local top = {}
  22         table.insert(stack, top)
  23         local ni,c,label,xarg, empty
  24         local i, j = 1, 1
  25         while true do
  26                 ni,j,c,label,xarg, empty = string.find(s, "<(%/?)(%w+)(.-)(%/?)>", j)
  27                 if not ni then break end
  28                 local text = string.sub(s, i, ni-1)
  29                 if not string.find(text, "^%s*$") then
  30                         table.insert(top, text)
  31                 end
  32                 if empty == "/" then  -- empty element tag
  33                         table.insert(top, {tag=label, attr=self:parseargs(xarg), empty=1})
  34                 elseif c == "" then   -- start tag
  35                         top = {tag=label, attr=self:parseargs(xarg)}
  36                         table.insert(stack, top)   -- new level
  37                 else  -- end tag
  38                 local toclose = table.remove(stack)  -- remove top
  39                 top = stack[#stack]
  40                 if #stack < 1 then
  41                         error("nothing to close with "..label)
  42                 end
  43                 if toclose.tag ~= label then
  44                         error("trying to close "..toclose.label.." with "..label)
  45                 end
  46                 table.insert(top, toclose)
  47         end
  48         i = j+1
  49 end
  50 local text = string.sub(s, i)
  51 if not string.find(text, "^%s*$") then
  52         table.insert(stack[stack.n], text)
  53 end
  54 if #stack > 1 then
  55         error("unclosed "..stack[stack.n].label)
  56 end
  57 return stack[1]
  58 end,
  59 }
  60
  61 return xml_parser