deb-spice-html5/spicedataview.js
Jeremy White f8f622157c initial
2012-06-04 17:22:01 +03:00

97 lines
2.8 KiB
JavaScript

"use strict";
/*
Copyright (C) 2012 by Jeremy P. White <jwhite@codeweavers.com>
This file is part of spice-html5.
spice-html5 is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
spice-html5 is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with spice-html5. If not, see <http://www.gnu.org/licenses/>.
*/
/*----------------------------------------------------------------------------
** SpiceDataView
** FIXME FIXME
** This is used because Firefox does not have DataView yet.
** We should use DataView if we have it, because it *has* to
** be faster than this code
**--------------------------------------------------------------------------*/
function SpiceDataView(buffer, byteOffset, byteLength)
{
if (byteOffset !== undefined)
{
if (byteLength !== undefined)
this.u8 = new Uint8Array(buffer, byteOffset, byteLength);
else
this.u8 = new Uint8Array(buffer, byteOffset);
}
else
this.u8 = new Uint8Array(buffer);
};
SpiceDataView.prototype = {
getUint8: function(byteOffset)
{
return this.u8[byteOffset];
},
getUint16: function(byteOffset, littleEndian)
{
var low = 1, high = 0;
if (littleEndian)
{
low = 0;
high = 1;
}
return (this.u8[byteOffset + high] << 8) | this.u8[byteOffset + low];
},
getUint32: function(byteOffset, littleEndian)
{
var low = 2, high = 0;
if (littleEndian)
{
low = 0;
high = 2;
}
return (this.getUint16(byteOffset + high, littleEndian) << 16) |
this.getUint16(byteOffset + low, littleEndian);
},
setUint8: function(byteOffset, b)
{
this.u8[byteOffset] = (b & 0xff);
},
setUint16: function(byteOffset, i, littleEndian)
{
var low = 1, high = 0;
if (littleEndian)
{
low = 0;
high = 1;
}
this.u8[byteOffset + high] = (i & 0xffff) >> 8;
this.u8[byteOffset + low] = (i & 0x00ff);
},
setUint32: function(byteOffset, w, littleEndian)
{
var low = 2, high = 0;
if (littleEndian)
{
low = 0;
high = 2;
}
this.setUint16(byteOffset + high, (w & 0xffffffff) >> 16, littleEndian);
this.setUint16(byteOffset + low, (w & 0x0000ffff), littleEndian);
},
}