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adler32.mjs
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adler32.mjs
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/* adler32.js (C) 2014-present SheetJS -- http://sheetjs.com */
/* vim: set ts=2: */
/*exported ADLER32 */
/*:: declare var DO_NOT_EXPORT_ADLER:?boolean; */
/*:: declare function define(cb:()=>any):void; */
var ADLER32/*:ADLER32Module*/;
(function (factory/*:(a:any)=>void*/)/*:void*/ {
/*jshint ignore:start */
/*eslint-disable */
if(typeof DO_NOT_EXPORT_ADLER === 'undefined') {
if('object' === typeof exports) {
factory(exports);
} else if ('function' === typeof define && /*::(*/define/*:: :any)*/.amd) {
define(function () {
var module/*:ADLER32Module*/ = /*::(*/{}/*:: :any)*/;
factory(module);
return module;
});
} else {
factory(ADLER32 = /*::(*/{}/*:: :any)*/);
}
} else {
factory(ADLER32 = /*::(*/{}/*:: :any)*/);
}
/*eslint-enable */
/*jshint ignore:end */
}(function(ADLER32/*:ADLER32Module*/) {
ADLER32.version = '1.3.0';
/*::
type ADLER32Type = number;
type ABuf = Array<number> | Buffer | Uint8Array;
*/
/*# consult README.md for the magic number */
/*# charCodeAt is the best approach for binary strings */
function adler32_bstr(bstr/*:string*/, seed/*:?ADLER32Type*/)/*:ADLER32Type*/ {
var a = 1, b = 0, L = bstr.length, M = 0;
if(typeof seed === 'number') { a = seed & 0xFFFF; b = seed >>> 16; }
for(var i = 0; i < L;) {
M = Math.min(L-i, 2654)+i;
for(;i<M;i++) {
a += bstr.charCodeAt(i)&0xFF;
b += a;
}
a = (15*(a>>>16)+(a&65535));
b = (15*(b>>>16)+(b&65535));
}
return ((b%65521) << 16) | (a%65521);
}
function adler32_buf(buf/*:ABuf*/, seed/*:?ADLER32Type*/)/*:ADLER32Type*/ {
var a = 1, b = 0, L = buf.length, M = 0;
if(typeof seed === 'number') { a = seed & 0xFFFF; b = (seed >>> 16) & 0xFFFF; }
for(var i = 0; i < L;) {
M = Math.min(L-i, 2654)+i;
for(;i<M;i++) {
a += buf[i]&0xFF;
b += a;
}
a = (15*(a>>>16)+(a&65535));
b = (15*(b>>>16)+(b&65535));
}
return ((b%65521) << 16) | (a%65521);
}
/*# much much faster to intertwine utf8 and adler */
function adler32_str(str/*:string*/, seed/*:?ADLER32Type*/)/*:ADLER32Type*/ {
var a = 1, b = 0, L = str.length, M = 0, c = 0, d = 0;
if(typeof seed === 'number') { a = seed & 0xFFFF; b = seed >>> 16; }
for(var i = 0; i < L;) {
M = Math.min(L-i, 2918);
while(M>0) {
c = str.charCodeAt(i++);
if(c < 0x80) { a += c; }
else if(c < 0x800) {
a += 192|((c>>6)&31); b += a; --M;
a += 128|(c&63);
} else if(c >= 0xD800 && c < 0xE000) {
c = (c&1023)+64; d = str.charCodeAt(i++) & 1023;
a += 240|((c>>8)&7); b += a; --M;
a += 128|((c>>2)&63); b += a; --M;
a += 128|((d>>6)&15)|((c&3)<<4); b += a; --M;
a += 128|(d&63);
} else {
a += 224|((c>>12)&15); b += a; --M;
a += 128|((c>>6)&63); b += a; --M;
a += 128|(c&63);
}
b += a; --M;
}
a = (15*(a>>>16)+(a&65535));
b = (15*(b>>>16)+(b&65535));
}
return ((b%65521) << 16) | (a%65521);
}
// $FlowIgnore
ADLER32.bstr = adler32_bstr;
// $FlowIgnore
ADLER32.buf = adler32_buf;
// $FlowIgnore
ADLER32.str = adler32_str;
}));