sheetjs/bits/37_xlsbutils.js

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function readIEEE754(buf, idx, isLE, nl, ml) {
if(isLE === undefined) isLE = true;
if(!nl) nl = 8;
if(!ml && nl === 8) ml = 52;
var e, m, el = nl * 8 - ml - 1, eMax = (1 << el) - 1, eBias = eMax >> 1;
var bits = -7, d = isLE ? -1 : 1, i = isLE ? (nl - 1) : 0, s = buf[idx + i];
i += d;
e = s & ((1 << (-bits)) - 1); s >>>= (-bits); bits += el;
for (; bits > 0; e = e * 256 + buf[idx + i], i += d, bits -= 8);
m = e & ((1 << (-bits)) - 1); e >>>= (-bits); bits += ml;
for (; bits > 0; m = m * 256 + buf[idx + i], i += d, bits -= 8);
if (e === eMax) return m ? NaN : ((s ? -1 : 1) * Infinity);
else if (e === 0) e = 1 - eBias;
else { m = m + Math.pow(2, ml); e = e - eBias; }
return (s ? -1 : 1) * m * Math.pow(2, e - ml);
}
var __toBuffer;
if(typeof Buffer !== "undefined") {
Buffer.prototype.hexlify= function() { return this.toString('hex'); };
__toBuffer = function(bufs) { return Buffer.concat(bufs[0]); };
} else {
__toBuffer = function(bufs) {
var x = [];
for(var i = 0; i != bufs[0].length; ++i) { x = x.concat(bufs[0][i]); }
return x;
};
}
var __readUInt8 = function(b, idx) { return b.readUInt8 ? b.readUInt8(idx) : b[idx]; };
var __readUInt16LE = function(b, idx) { return b.readUInt16LE ? b.readUInt16LE(idx) : b[idx+1]*(1<<8)+b[idx]; };
var __readInt16LE = function(b, idx) { var u = __readUInt16LE(b,idx); if(!(u & 0x8000)) return u; return (0xffff - u + 1) * -1; };
var __readUInt32LE = function(b, idx) { return b.readUInt32LE ? b.readUInt32LE(idx) : b[idx+3]*(1<<24)+b[idx+2]*(1<<16)+b[idx+1]*(1<<8)+b[idx]; };
var __readInt32LE = function(b, idx) { if(b.readInt32LE) return b.readInt32LE(idx); var u = __readUInt32LE(b,idx); if(!(u & 0x80000000)) return u; return (0xffffffff - u + 1) * -1; };
var __readDoubleLE = function(b, idx) { return b.readDoubleLE ? b.readDoubleLE(idx) : readIEEE754(b, idx||0);};
function ReadShift(size, t) {
var o = "", oo = [], w, vv, i, loc; t = t || 'u';
if(size === 'ieee754') { size = 8; t = 'f'; }
switch(size) {
case 1: o = __readUInt8(this, this.l); break;
case 2: o=(t==='u' ? __readUInt16LE : __readInt16LE)(this, this.l); break;
case 4: o = __readUInt32LE(this, this.l); break;
case 8: if(t === 'f') { o = __readDoubleLE(this, this.l); break; }
/* falls through */
case 16: o = this.toString('hex', this.l,this.l+size); break;
case 'dbcs': size = 2*t; loc = this.l;
for(i = 0; i != t; ++i) {
oo.push(_getchar(__readUInt16LE(this, loc)));
loc+=2;
} o = oo.join(""); break;
case 'sbcs': size = t; o = ""; loc = this.l;
for(i = 0; i != t; ++i) {
o += _getchar(__readUInt8(this, loc));
loc+=1;
} break;
}
this.l+=size; return o;
}
function prep_blob(blob, pos) {
blob.read_shift = ReadShift.bind(blob);
blob.l = pos || 0;
var read = ReadShift.bind(blob);
return [read];
}
function parsenoop(blob, length) { blob.l += length; }