pluie-bin/lib/bin.js
2016-12-18 14:44:45 +01:00

97 lines
3.1 KiB
JavaScript
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

'use strict';
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
String.prototype.removeEndNullBytes = function() {
return this.replace(/\0+$/g, '');
}
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
String.prototype.removeStartNullBytes = function() {
return this.replace(/^\0+/g, '');
}
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
var bin =
{
enc : new TextEncoder("utf-8"),
dec : new TextDecoder("utf-8", {fatal: true}),
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
intFromBytes : function(bytes)
{
var value = null;
if (bytes!=null && bytes.length > 0) {
// Big Endian
for (var i = value = 0, lim = bytes.length; i < lim; i++) {
value = value * 256 + bytes[i];
}
}
return value;
},
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bytesFromInt : function(value, size)
{
var bytes = new Uint8Array(size);
while (value) {
bytes.set([value & 255], --size);
value >>= 8;
}
return bytes;
},
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pack : function(size, type, value)
{
var packed = null
if (type == 'n' || type == 'N') {
// js int max on 32 signed bits
if (value >= 0 && value <= 2147483647) {
packed = this.bytesFromInt(value, type == 'n' ? 2 : 4);
}
}
else if (type == 'a') {
packed = new Uint8Array(size);
packed.set(this.enc.encode(value), 0);
}
return packed;
},
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
unpack : function(size, type, bytes)
{
var unpacked = null
if (type == 'n' || type == 'N') {
var selByte = bytes.slice(0, size*(type == 'n' ? 2 : 4));
unpacked = this.intFromBytes(selByte);
}
else if (type == 'a') {
unpacked = this.dec.decode(bytes.slice(0, size)).removeEndNullBytes();
}
return unpacked;
},
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mergeBuffers : function(bufferArray)
{
var maxLength = 0;
for(var i=0, lim=bufferArray.length; i < lim; i++) {
if (bufferArray[i] != null) {
maxLength += bufferArray[i].byteLength;
}
}
var tmp = new Uint8Array(maxLength);
for(var i=0, pos = 0, lim=bufferArray.length; i < lim; i++) {
if (bufferArray[i] != null) {
tmp.set(new Uint8Array(bufferArray[i]), pos);
pos += bufferArray[i].byteLength;
}
}
return tmp;
},
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
getBuffer : function(array, size)
{
var buffer = new Uint8Array(!size ? array.length : size);
buffer.set(new Uint8Array(array), 0);
return buffer;
},
}
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
require('./file')(bin);
module.exports = bin;