105 lines
2.2 KiB
JavaScript
105 lines
2.2 KiB
JavaScript
|
|
||
|
|
/**
|
||
|
|
* Module dependencies.
|
||
|
|
*/
|
||
|
|
|
||
|
|
var Stream = require('stream').Writable;
|
||
|
|
var encode = require('./encode');
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Expose parser.
|
||
|
|
*/
|
||
|
|
|
||
|
|
module.exports = Parser;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Initialize parser.
|
||
|
|
*
|
||
|
|
* @param {Options} [opts]
|
||
|
|
* @api public
|
||
|
|
*/
|
||
|
|
|
||
|
|
function Parser(opts) {
|
||
|
|
Stream.call(this, opts);
|
||
|
|
this.state = 'message';
|
||
|
|
this._lenbuf = new Buffer(4);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Inherit from `Stream.prototype`.
|
||
|
|
*/
|
||
|
|
|
||
|
|
Parser.prototype.__proto__ = Stream.prototype;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Write implementation.
|
||
|
|
*/
|
||
|
|
|
||
|
|
Parser.prototype._write = function(chunk, encoding, fn){
|
||
|
|
for (var i = 0; i < chunk.length; i++) {
|
||
|
|
switch (this.state) {
|
||
|
|
case 'message':
|
||
|
|
var meta = chunk[i];
|
||
|
|
this.version = meta >> 4;
|
||
|
|
this.argv = meta & 0xf;
|
||
|
|
this.state = 'arglen';
|
||
|
|
this._bufs = [new Buffer([meta])];
|
||
|
|
this._nargs = 0;
|
||
|
|
this._leni = 0;
|
||
|
|
break;
|
||
|
|
|
||
|
|
case 'arglen':
|
||
|
|
this._lenbuf[this._leni++] = chunk[i];
|
||
|
|
|
||
|
|
// done
|
||
|
|
if (4 == this._leni) {
|
||
|
|
this._arglen = this._lenbuf.readUInt32BE(0);
|
||
|
|
var buf = new Buffer(4);
|
||
|
|
buf[0] = this._lenbuf[0];
|
||
|
|
buf[1] = this._lenbuf[1];
|
||
|
|
buf[2] = this._lenbuf[2];
|
||
|
|
buf[3] = this._lenbuf[3];
|
||
|
|
this._bufs.push(buf);
|
||
|
|
this._argcur = 0;
|
||
|
|
this.state = 'arg';
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
|
||
|
|
case 'arg':
|
||
|
|
// bytes remaining in the argument
|
||
|
|
var rem = this._arglen - this._argcur;
|
||
|
|
|
||
|
|
// consume the chunk we need to complete
|
||
|
|
// the argument, or the remainder of the
|
||
|
|
// chunk if it's not mixed-boundary
|
||
|
|
var pos = Math.min(rem + i, chunk.length);
|
||
|
|
|
||
|
|
// slice arg chunk
|
||
|
|
var part = chunk.slice(i, pos);
|
||
|
|
this._bufs.push(part);
|
||
|
|
|
||
|
|
// check if we have the complete arg
|
||
|
|
this._argcur += pos - i;
|
||
|
|
var done = this._argcur == this._arglen;
|
||
|
|
i = pos - 1;
|
||
|
|
|
||
|
|
if (done) this._nargs++;
|
||
|
|
|
||
|
|
// no more args
|
||
|
|
if (this._nargs == this.argv) {
|
||
|
|
this.state = 'message';
|
||
|
|
this.emit('data', Buffer.concat(this._bufs));
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (done) {
|
||
|
|
this.state = 'arglen';
|
||
|
|
this._leni = 0;
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
fn();
|
||
|
|
};
|