Buffer.byteLength = SlowBuffer.byteLength = function(str, encoding) { encoding = String(encoding || 'utf8').toLowerCase(); // Use native conversion when possible if (Buffer.isNativeEncoding(encoding)) return original.BufferByteLength.call(this, str, encoding); // Slow, I know, but we don't have a better way yet. return iconv.encode(str, encoding).length; }
SlowBuffer.prototype.toString = function(encoding, start, end) { encoding = String(encoding || 'utf8').toLowerCase(); // Use native conversion when possible if (Buffer.isNativeEncoding(encoding)) return original.SlowBufferToString.call(this, encoding, start, end); // Otherwise, use our decoding method. if (typeof start == 'undefined') start = 0; if (typeof end == 'undefined') end = this.length; return iconv.decode(this.slice(start, end), encoding); }
Buffer.prototype.write = function(string, offset, length, encoding) { var _offset = offset, _length = length, _encoding = encoding; // Support both (string, offset, length, encoding) // and the legacy (string, encoding, offset, length) if (isFinite(offset)) { if (!isFinite(length)) { encoding = length; length = undefined; } } else { // legacy var swap = encoding; encoding = offset; offset = length; length = swap; } encoding = String(encoding || 'utf8').toLowerCase(); // Use native conversion when possible if (Buffer.isNativeEncoding(encoding)) return original.BufferWrite.call(this, string, _offset, _length, _encoding); offset = +offset || 0; var remaining = this.length - offset; if (!length) { length = remaining; } else { length = +length; if (length > remaining) { length = remaining; } } if (string.length > 0 && (length < 0 || offset < 0)) throw new RangeError('attempt to write beyond buffer bounds'); // Otherwise, use our encoding method. var buf = iconv.encode(string, encoding); if (buf.length < length) length = buf.length; buf.copy(this, offset, 0, length); return length; // TODO: Set _charsWritten. }
Buffer.isEncoding = function(encoding) { return Buffer.isNativeEncoding(encoding) || iconv.encodingExists(encoding); }