Firmware/Marlin/configurator/js/binarystring.js

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JavaScript
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function BinaryString(source) {
this._source = null;
this._bytes = [];
this._pos = 0;
this._length = 0;
this._init = function(source) {
this._source = source;
this._bytes = this._stringToBytes(this._source);
this._length = this._bytes.length;
}
this.current = function() {return this._pos;}
this.rewind = function() {return this.jump(0);}
this.end = function() {return this.jump(this.length() - 1);}
this.next = function() {return this.jump(this.current() + 1);}
this.prev = function() {return this.jump(this.current() - 1);}
this.jump = function(pos) {
if (pos < 0 || pos >= this.length()) return false;
this._pos = pos;
return true;
}
this.readByte = function(pos) {
pos = (typeof pos == 'number') ? pos : this.current();
return this.readBytes(1, pos)[0];
}
this.readBytes = function(length, pos) {
length = length || 1;
pos = (typeof pos == 'number') ? pos : this.current();
if (pos > this.length() ||
pos < 0 ||
length <= 0 ||
pos + length > this.length() ||
pos + length < 0
) {
return false;
}
var bytes = [];
for (var i = pos; i < pos + length; i++) {
bytes.push(this._bytes[i]);
}
return bytes;
}
this.length = function() {return this._length;}
this.toString = function() {
var string = '',
length = this.length();
for (var i = 0; i < length; i++) {
string += String.fromCharCode(this.readByte(i));
}
return string;
}
this.toUtf8 = function() {
var inc = 0,
string = '',
length = this.length();
// determine if first 3 characters are the BOM
// then skip them in output if so
if (length >= 3 &&
this.readByte(0) === 0xEF &&
this.readByte(1) === 0xBB &&
this.readByte(2) === 0xBF
) {
inc = 3;
}
for (; inc < length; inc++) {
var byte1 = this.readByte(inc),
byte2 = 0,
byte3 = 0,
byte4 = 0,
code1 = 0,
code2 = 0,
point = 0;
switch (true) {
// single byte character; same as ascii
case (byte1 < 0x80):
code1 = byte1;
break;
// 2 byte character
case (byte1 >= 0xC2 && byte1 < 0xE0):
byte2 = this.readByte(++inc);
code1 = ((byte1 & 0x1F) << 6) +
(byte2 & 0x3F);
break;
// 3 byte character
case (byte1 >= 0xE0 && byte1 < 0xF0):
byte2 = this.readByte(++inc);
byte3 = this.readByte(++inc);
code1 = ((byte1 & 0xFF) << 12) +
((byte2 & 0x3F) << 6) +
(byte3 & 0x3F);
break;
// 4 byte character
case (byte1 >= 0xF0 && byte1 < 0xF5):
byte2 = this.readByte(++inc);
byte3 = this.readByte(++inc);
byte4 = this.readByte(++inc);
point = ((byte1 & 0x07) << 18) +
((byte2 & 0x3F) << 12) +
((byte3 & 0x3F) << 6) +
(byte4 & 0x3F)
point -= 0x10000;
code1 = (point >> 10) + 0xD800;
code2 = (point & 0x3FF) + 0xDC00;
break;
default:
throw 'Invalid byte ' + this._byteToString(byte1) + ' whilst converting to UTF-8';
break;
}
string += (code2) ? String.fromCharCode(code1, code2)
: String.fromCharCode(code1);
}
return string;
}
this.toArray = function() {return this.readBytes(this.length() - 1, 0);}
this._stringToBytes = function(str) {
var bytes = [],
chr = 0;
for (var i = 0; i < str.length; i++) {
chr = str.charCodeAt(i);
bytes.push(chr & 0xFF);
}
return bytes;
}
this._byteToString = function(byte) {
var asString = byte.toString(16).toUpperCase();
while (asString.length < 2) {
asString = '0' + asString;
}
return '0x' + asString;
}
this._init(source);
}