--- /dev/null
+
+// Export Node.js internal encodings.
+
+var utf16lebom = new Buffer([0xFF, 0xFE]);
+
+module.exports = {
+ // Encodings
+ utf8: { type: "_internal", enc: "utf8" },
+ cesu8: { type: "_internal", enc: "utf8" },
+ unicode11utf8: { type: "_internal", enc: "utf8" },
+ ucs2: { type: "_internal", enc: "ucs2", bom: utf16lebom },
+ utf16le:{ type: "_internal", enc: "ucs2", bom: utf16lebom },
+ binary: { type: "_internal", enc: "binary" },
+ base64: { type: "_internal", enc: "base64" },
+ hex: { type: "_internal", enc: "hex" },
+
+ // Codec.
+ _internal: function(options) {
+ if (!options || !options.enc)
+ throw new Error("Internal codec is called without encoding type.")
+
+ return {
+ encoder: options.enc == "base64" ? encoderBase64 : encoderInternal,
+ decoder: decoderInternal,
+
+ enc: options.enc,
+ bom: options.bom,
+ };
+ },
+};
+
+// We use node.js internal decoder. It's signature is the same as ours.
+var StringDecoder = require('string_decoder').StringDecoder;
+
+if (!StringDecoder.prototype.end) // Node v0.8 doesn't have this method.
+ StringDecoder.prototype.end = function() {};
+
+function decoderInternal() {
+ return new StringDecoder(this.enc);
+}
+
+// Encoder is mostly trivial
+
+function encoderInternal() {
+ return {
+ write: encodeInternal,
+ end: function() {},
+
+ enc: this.enc,
+ }
+}
+
+function encodeInternal(str) {
+ return new Buffer(str, this.enc);
+}
+
+
+// Except base64 encoder, which must keep its state.
+
+function encoderBase64() {
+ return {
+ write: encodeBase64Write,
+ end: encodeBase64End,
+
+ prevStr: '',
+ };
+}
+
+function encodeBase64Write(str) {
+ str = this.prevStr + str;
+ var completeQuads = str.length - (str.length % 4);
+ this.prevStr = str.slice(completeQuads);
+ str = str.slice(0, completeQuads);
+
+ return new Buffer(str, "base64");
+}
+
+function encodeBase64End() {
+ return new Buffer(this.prevStr, "base64");
+}
+