diff options
Diffstat (limited to 'node_modules/stringstream/stringstream.js')
-rw-r--r-- | node_modules/stringstream/stringstream.js | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/node_modules/stringstream/stringstream.js b/node_modules/stringstream/stringstream.js new file mode 100644 index 000000000..4ece1275f --- /dev/null +++ b/node_modules/stringstream/stringstream.js @@ -0,0 +1,102 @@ +var util = require('util') +var Stream = require('stream') +var StringDecoder = require('string_decoder').StringDecoder + +module.exports = StringStream +module.exports.AlignedStringDecoder = AlignedStringDecoder + +function StringStream(from, to) { + if (!(this instanceof StringStream)) return new StringStream(from, to) + + Stream.call(this) + + if (from == null) from = 'utf8' + + this.readable = this.writable = true + this.paused = false + this.toEncoding = (to == null ? from : to) + this.fromEncoding = (to == null ? '' : from) + this.decoder = new AlignedStringDecoder(this.toEncoding) +} +util.inherits(StringStream, Stream) + +StringStream.prototype.write = function(data) { + if (!this.writable) { + var err = new Error('stream not writable') + err.code = 'EPIPE' + this.emit('error', err) + return false + } + if (this.fromEncoding) { + if (Buffer.isBuffer(data)) data = data.toString() + data = new Buffer(data, this.fromEncoding) + } + var string = this.decoder.write(data) + if (string.length) this.emit('data', string) + return !this.paused +} + +StringStream.prototype.flush = function() { + if (this.decoder.flush) { + var string = this.decoder.flush() + if (string.length) this.emit('data', string) + } +} + +StringStream.prototype.end = function() { + if (!this.writable && !this.readable) return + this.flush() + this.emit('end') + this.writable = this.readable = false + this.destroy() +} + +StringStream.prototype.destroy = function() { + this.decoder = null + this.writable = this.readable = false + this.emit('close') +} + +StringStream.prototype.pause = function() { + this.paused = true +} + +StringStream.prototype.resume = function () { + if (this.paused) this.emit('drain') + this.paused = false +} + +function AlignedStringDecoder(encoding) { + StringDecoder.call(this, encoding) + + switch (this.encoding) { + case 'base64': + this.write = alignedWrite + this.alignedBuffer = new Buffer(3) + this.alignedBytes = 0 + break + } +} +util.inherits(AlignedStringDecoder, StringDecoder) + +AlignedStringDecoder.prototype.flush = function() { + if (!this.alignedBuffer || !this.alignedBytes) return '' + var leftover = this.alignedBuffer.toString(this.encoding, 0, this.alignedBytes) + this.alignedBytes = 0 + return leftover +} + +function alignedWrite(buffer) { + var rem = (this.alignedBytes + buffer.length) % this.alignedBuffer.length + if (!rem && !this.alignedBytes) return buffer.toString(this.encoding) + + var returnBuffer = new Buffer(this.alignedBytes + buffer.length - rem) + + this.alignedBuffer.copy(returnBuffer, 0, 0, this.alignedBytes) + buffer.copy(returnBuffer, this.alignedBytes, 0, buffer.length - rem) + + buffer.copy(this.alignedBuffer, 0, buffer.length - rem, buffer.length) + this.alignedBytes = rem + + return returnBuffer.toString(this.encoding) +} |