3 var StreamReader = function() {
9 StreamReader.prototype.put = function(buffer) {
10 if (!buffer || buffer.length === 0) return;
11 if (!buffer.copy) buffer = new Buffer(buffer);
12 this._queue.push(buffer);
13 this._queueSize += buffer.length;
16 StreamReader.prototype.read = function(length) {
17 if (length > this._queueSize) return null;
18 if (length === 0) return new Buffer(0);
20 this._queueSize -= length;
22 var queue = this._queue,
27 if (first.length >= length) {
28 if (first.length === length) {
31 buffer = first.slice(0, length);
32 queue[0] = first.slice(length);
37 for (var i = 0, n = queue.length; i < n; i++) {
38 if (remain < queue[i].length) break;
39 remain -= queue[i].length;
41 buffers = queue.splice(0, i);
43 if (remain > 0 && queue.length > 0) {
44 buffers.push(queue[0].slice(0, remain));
45 queue[0] = queue[0].slice(remain);
47 return this._concat(buffers, length);
50 StreamReader.prototype.eachByte = function(callback, context) {
53 while (this._queue.length > 0) {
54 buffer = this._queue[0];
57 while (this._offset < n) {
60 callback.call(context, buffer[index]);
67 StreamReader.prototype._concat = function(buffers, length) {
68 if (Buffer.concat) return Buffer.concat(buffers, length);
70 var buffer = new Buffer(length),
73 for (var i = 0, n = buffers.length; i < n; i++) {
74 buffers[i].copy(buffer, offset);
75 offset += buffers[i].length;
80 module.exports = StreamReader;