1 files changed, 52 insertions, 3 deletions
diff --git a/util/http.lua b/util/http.lua
index 5b49d1d0..f7259920 100644
--- a/util/http.lua
+++ b/util/http.lua
@@ -5,11 +5,60 @@
 -- COPYING file in the source package for more information.
 --
 
-local http = {};
+local format, char = string.format, string.char;
+local pairs, ipairs, tonumber = pairs, ipairs, tonumber;
+local t_insert, t_concat = table.insert, table.concat;
 
-function http.contains_token(field, token)
+local function urlencode(s)
+	return s and (s:gsub("[^a-zA-Z0-9.~_-]", function (c) return format("%%%02x", c:byte()); end));
+end
+local function urldecode(s)
+	return s and (s:gsub("%%(%x%x)", function (c) return char(tonumber(c,16)); end));
+end
+
+local function _formencodepart(s)
+	return s and (s:gsub("%W", function (c)
+		if c ~= " " then
+			return format("%%%02x", c:byte());
+		else
+			return "+";
+		end
+	end));
+end
+
+local function formencode(form)
+	local result = {};
+	if form[1] then -- Array of ordered { name, value }
+		for _, field in ipairs(form) do
+			t_insert(result, _formencodepart(field.name).."=".._formencodepart(field.value));
+		end
+	else -- Unordered map of name -> value
+		for name, value in pairs(form) do
+			t_insert(result, _formencodepart(name).."=".._formencodepart(value));
+		end
+	end
+	return t_concat(result, "&");
+end
+
+local function formdecode(s)
+	if not s:match("=") then return urldecode(s); end
+	local r = {};
+	for k, v in s:gmatch("([^=&]*)=([^&]*)") do
+		k, v = k:gsub("%+", "%%20"), v:gsub("%+", "%%20");
+		k, v = urldecode(k), urldecode(v);
+		t_insert(r, { name = k, value = v });
+		r[k] = v;
+	end
+	return r;
+end
+
+local function contains_token(field, token)
 	field = ","..field:gsub("[ \t]", ""):lower()..",";
 	return field:find(","..token:lower()..",", 1, true) ~= nil;
 end
 
-return http;
+return {
+	urlencode = urlencode, urldecode = urldecode;
+	formencode = formencode, formdecode = formdecode;
+	contains_token = contains_token;
+};