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*$") then
  30                         table.insert(top, text)
  31                 end
  32                 local inserted = nil
  33                 if empty == "/" then  -- empty element tag
  34                         inserted = {tag=label, attr=self:parseargs(xarg), empty=1}
  35                         table.insert(top, inserted)
  36                 elseif c == "" then   -- start tag
  37                         top = {tag=label, attr=self:parseargs(xarg)}
  38                         inserted = top
  39                         table.insert(stack, top)   -- new level
  40                 else  -- end tag
  41             local toclose = table.remove(stack)  -- remove top
  42                         top = stack[#stack]
  43                         if #stack < 1 then
  44                                 error("nothing to close with "..label)
  45                         end
  46                         if toclose.tag ~= label then
  47                                 error("trying to close "..toclose.label.." with "..label)
  48                         end
  49                         table.insert(top, toclose)
  50                 end
  51                 if inserted then
  52                         for a, v in pairs(inserted.attr) do
  53                                 if type(self[a])=='table' then
  54                                         self[a][v] = inserted
  55                                 end
  56                         end
  57                 end
  58                 i = j+1
  59         end
  60         local text = string.sub(s, i)
  61         if not string.find(text, "^%s*$") then
  62                 table.insert(stack[stack.n], text)
  63         end
  64         if #stack > 1 then
  65                 error("unclosed "..stack[stack.n].label)
  66         end
  67         return stack[1]
  68 end,
  69 }
  70
  71 return xml_parser