ionic
Version:
A tool for creating and developing Ionic Framework mobile apps.
44 lines (34 loc) • 1 kB
JavaScript
var StreamReader = function() {
this._queue = [];
this._cursor = 0;
};
StreamReader.prototype.read = function(bytes) {
return this._readBuffer(bytes);
};
StreamReader.prototype.put = function(buffer) {
if (!buffer || buffer.length === 0) return;
if (!buffer.copy) buffer = new Buffer(buffer);
this._queue.push(buffer);
};
StreamReader.prototype._readBuffer = function(length) {
var buffer = new Buffer(length),
queue = this._queue,
remain = length,
n = queue.length,
i = 0,
chunk, offset, size;
if (remain === 0) return buffer;
while (remain > 0 && i < n) {
chunk = queue[i];
offset = (i === 0) ? this._cursor : 0;
size = Math.min(remain, chunk.length - offset);
chunk.copy(buffer, length - remain, offset, offset + size);
remain -= size;
i += 1;
}
if (remain > 0) return null;
queue.splice(0, i-1);
this._cursor = (i === 1 ? this._cursor : 0) + size;
return buffer;
};
module.exports = StreamReader;