--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/net/http/parser.lua	Sun Apr 08 04:09:33 2012 +0500
@@ -0,0 +1,116 @@
+
+local tonumber = tonumber;
+local assert = assert;
+
+local httpstream = {};
+
+function httpstream.new(success_cb, error_cb, parser_type, options_cb)
+	local client = true;
+	if not parser_type or parser_type == "server" then client = false; else assert(parser_type == "client", "Invalid parser type"); end
+	local buf = "";
+	local chunked;
+	local state = nil;
+	local packet;
+	local len;
+	local have_body;
+	local error;
+	return {
+		feed = function(self, data)
+			if error then return nil, "parse has failed"; end
+			if not data then -- EOF
+				if state and client and not len then -- reading client body until EOF
+					packet.body = buf;
+					success_cb(packet);
+				elseif buf ~= "" then -- unexpected EOF
+					error = true; return error_cb();
+				end
+				return;
+			end
+			buf = buf..data;
+			while #buf > 0 do
+				if state == nil then -- read request
+					local index = buf:find("\r\n\r\n", nil, true);
+					if not index then return; end -- not enough data
+					local method, path, httpversion, status_code, reason_phrase;
+					local first_line;
+					local headers = {};
+					for line in buf:sub(1,index+1):gmatch("([^\r\n]+)\r\n") do -- parse request
+						if first_line then
+							local key, val = line:match("^([^%s:]+): *(.*)$");
+							if not key then error = true; return error_cb("invalid-header-line"); end -- TODO handle multi-line and invalid headers
+							key = key:lower();
+							headers[key] = headers[key] and headers[key]..","..val or val;
+						else
+							first_line = line;
+							if client then
+								httpversion, status_code, reason_phrase = line:match("^HTTP/(1%.[01]) (%d%d%d) (.*)$");
+								if not status_code then error = true; return error_cb("invalid-status-line"); end
+								have_body = not
+									 ( (options_cb and options_cb().method == "HEAD")
+									or (status_code == 204 or status_code == 304 or status_code == 301)
+									or (status_code >= 100 and status_code < 200) );
+								chunked = have_body and headers["transfer-encoding"] == "chunked";
+							else
+								method, path, httpversion = line:match("^(%w+) (%S+) HTTP/(1%.[01])$");
+								if not method then error = true; return error_cb("invalid-status-line"); end
+								path = path:gsub("^//+", "/"); -- TODO parse url more
+							end
+						end
+					end
+					len = tonumber(headers["content-length"]); -- TODO check for invalid len
+					if client then
+						-- FIXME handle '100 Continue' response (by skipping it)
+						if not have_body then len = 0; end
+						packet = {
+							code = status_code;
+							httpversion = httpversion;
+							headers = headers;
+							body = have_body and "" or nil;
+							-- COMPAT the properties below are deprecated
+							responseversion = httpversion;
+							responseheaders = headers;
+						};
+					else
+						len = len or 0;
+						packet = {
+							method = method;
+							path = path;
+							httpversion = httpversion;
+							headers = headers;
+							body = nil;
+						};
+					end
+					buf = buf:sub(index + 4);
+					state = true;
+				end
+				if state then -- read body
+					if client then
+						if chunked then
+							local index = buf:find("\r\n", nil, true);
+							if not index then return; end -- not enough data
+							local chunk_size = buf:match("^%x+");
+							if not chunk_size then error = true; return error_cb("invalid-chunk-size"); end
+							chunk_size = tonumber(chunk_size, 16);
+							index = index + 2;
+							if chunk_size == 0 then
+								state = nil; success_cb(packet);
+							elseif #buf - index + 1 >= chunk_size then -- we have a chunk
+								packet.body = packet.body..buf:sub(index, index + chunk_size - 1);
+								buf = buf:sub(index + chunk_size);
+							end
+							error("trailers"); -- FIXME MUST read trailers
+						elseif len and #buf >= len then
+							packet.body, buf = buf:sub(1, len), buf:sub(len + 1);
+							state = nil; success_cb(packet);
+						end
+					elseif #buf >= len then
+						packet.body, buf = buf:sub(1, len), buf:sub(len + 1);
+						state = nil; success_cb(packet);
+					end
+				end
+			end
+		end;
+	};
+end
+
+return httpstream;