1.23.1

buffer-peek-stream.js
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			var stream = require('stream');
			var util = require('util');

			function peek(source, bytes, callback) {
			if (!callback) return peek(source, undefined, bytes);

			var dest = new BufferPeekStream({peekBytes: bytes});

			dest.once('peek', function (buffer) {
			callback(null, buffer, dest);
			});

			return source.pipe(dest);
			}
			peek.BufferPeekStream = BufferPeekStream;

			module.exports = peek;


			function BufferPeekStream(opts) {
			if (!opts) opts = {};

			opts.highWaterMark = opts.peekBytes \|\| 65536;

			stream.Transform.call(this, opts);

			this._peekState = {
			buffer: [],
			bytes: 0,
			maxBytes: opts.peekBytes \|\| 65536,
			peeked: false
			};
			}

			util.inherits(BufferPeekStream, stream.Transform);


			BufferPeekStream.prototype._transform = function _transform(chunk, enc, callback) {
			var state = this._peekState;

			// buffer incoming chunks until we have enough for our peek
			state.buffer.push(chunk);
			state.bytes += chunk.length;

			// get more?
			if (state.bytes >= state.maxBytes) _peek(this, callback);
			else callback();
			};


			BufferPeekStream.prototype._flush = function _flush(callback) {
			if (this._peekState.peeked) callback();
			else _peek(this, callback);
			};


			function _peek(stream, callback) {
			var state = stream._peekState;

			var buffer = Buffer.concat(state.buffer);

			// emit exactly the number of bytes we wanted to peek
			stream.emit('peek', buffer.slice(0, state.maxBytes));

			stream.push(buffer);

			state.buffer = null;
			state.bytes = null;
			state.peeked = true;

			stream._transform = passthrough;

			callback();
			}

			function passthrough(chunk, enc, callback) {
			this.push(chunk);
			callback();
			}