compound-ex4
Version:
Compound-ex4 - MVC framework for NodeJS (ExpressJs 4 version), fork compoundjs(https://github.com/1602/compound)
120 lines (88 loc) • 3.44 kB
JavaScript
// Export Node.js internal encodings.
module.exports = {
// Encodings
utf8: { type: "_internal", bomAware: true},
cesu8: { type: "_internal", bomAware: true},
unicode11utf8: "utf8",
ucs2: { type: "_internal", bomAware: true},
utf16le: "ucs2",
binary: { type: "_internal" },
base64: { type: "_internal" },
hex: { type: "_internal" },
// Codec.
_internal: InternalCodec,
};
//------------------------------------------------------------------------------
function InternalCodec(codecOptions) {
this.enc = codecOptions.encodingName;
this.bomAware = codecOptions.bomAware;
if (this.enc === "base64")
this.encoder = InternalEncoderBase64;
else if (this.enc === "cesu8") {
this.enc = "utf8"; // Use utf8 for decoding.
this.encoder = InternalEncoderCesu8;
}
}
InternalCodec.prototype.encoder = InternalEncoder;
InternalCodec.prototype.decoder = InternalDecoder;
//------------------------------------------------------------------------------
// 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 InternalDecoder(options, codec) {
StringDecoder.call(this, codec.enc);
}
InternalDecoder.prototype = StringDecoder.prototype;
//------------------------------------------------------------------------------
// Encoder is mostly trivial
function InternalEncoder(options, codec) {
this.enc = codec.enc;
}
InternalEncoder.prototype.write = function(str) {
return new Buffer(str, this.enc);
}
InternalEncoder.prototype.end = function() {
}
//------------------------------------------------------------------------------
// Except base64 encoder, which must keep its state.
function InternalEncoderBase64(options, codec) {
this.prevStr = '';
}
InternalEncoderBase64.prototype.write = function(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");
}
InternalEncoderBase64.prototype.end = function() {
return new Buffer(this.prevStr, "base64");
}
//------------------------------------------------------------------------------
// CESU-8 encoder is also special.
function InternalEncoderCesu8(options, codec) {
}
InternalEncoderCesu8.prototype.write = function(str) {
var buf = new Buffer(str.length * 3), bufIdx = 0;
for (var i = 0; i < str.length; i++) {
var charCode = str.charCodeAt(i);
// Naive implementation, but it works because CESU-8 is especially easy
// to convert from UTF-16 (which all JS strings are encoded in).
if (charCode < 0x80)
buf[bufIdx++] = charCode;
else if (charCode < 0x800) {
buf[bufIdx++] = 0xC0 + (charCode >>> 6);
buf[bufIdx++] = 0x80 + (charCode & 0x3f);
}
else { // charCode will always be < 0x10000 in javascript.
buf[bufIdx++] = 0xE0 + (charCode >>> 12);
buf[bufIdx++] = 0x80 + ((charCode >>> 6) & 0x3f);
buf[bufIdx++] = 0x80 + (charCode & 0x3f);
}
}
return buf.slice(0, bufIdx);
}
InternalEncoderCesu8.prototype.end = function() {
}