forked from serialport/node-serialport
/
parsers.js
65 lines (60 loc) · 1.94 KB
/
parsers.js
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/*jslint node: true */
'use strict';
// Copyright 2011 Chris Williams <chris@iterativedesigns.com>
module.exports = {
raw: function (emitter, buffer) {
emitter.emit('data', buffer);
},
//encoding: ascii utf8 utf16le ucs2 base64 binary hex
//More: http://nodejs.org/api/buffer.html#buffer_buffer
readline: function (delimiter, encoding) {
if (typeof delimiter === 'undefined' || delimiter === null) { delimiter = '\r'; }
if (typeof encoding === 'undefined' || encoding === null) { encoding = 'utf8'; }
// Delimiter buffer saved in closure
var data = '';
return function (emitter, buffer) {
// Collect data
data += buffer.toString(encoding);
// Split collected data by delimiter
var parts = data.split(delimiter);
data = parts.pop();
parts.forEach(function (part) {
emitter.emit('data', part);
});
};
},
// Emit a data event every `length` bytes
byteLength: function(length) {
var data = new Buffer(0);
return function(emitter, buffer){
data = Buffer.concat([data, buffer]);
while (data.length >= length) {
var out = data.slice(0,length);
data = data.slice(length);
emitter.emit('data', out);
}
};
},
//Emit a data event each time a byte sequence (delimiter is an array of byte) is found
//Sample usage : byteDelimiter([10, 13])
byteDelimiter: function (delimiter) {
if( Object.prototype.toString.call( delimiter ) !== '[object Array]' ){
delimiter = [ delimiter ];
}
var buf = [];
var nextDelimIndex = 0;
return function (emitter, buffer) {
for (var i = 0; i < buffer.length; i++) {
buf[buf.length] = buffer[i];
if(buf[buf.length-1] === delimiter[nextDelimIndex]) {
nextDelimIndex++;
}
if(nextDelimIndex === delimiter.length) {
emitter.emit('data', buf);
buf = [];
nextDelimIndex = 0;
}
}
};
}
};