SheetJS
e1c9c5e5cd
- normalized crc iteration logic - added browser demo - added command line tool crc32 - fixed unicode baseline script (node 6 changed default array printing) - fixed performance tests (benchmark module changed behavior) - updated travis versions for test - miscellaneous adjustments to tooling
68 lines
2.2 KiB
JavaScript
68 lines
2.2 KiB
JavaScript
/*# charCodeAt is the best approach for binary strings */
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/*global Buffer */
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var use_buffer = typeof Buffer !== 'undefined';
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function crc32_bstr(bstr/*:string*/)/*:CRC32Type*/ {
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if(bstr.length > 32768) if(use_buffer) return crc32_buf_8(new Buffer(bstr));
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var C = -1, L = bstr.length - 1;
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for(var i = 0; i < L;) {
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C = (C>>>8) ^ T[(C^bstr.charCodeAt(i++))&0xFF];
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C = (C>>>8) ^ T[(C^bstr.charCodeAt(i++))&0xFF];
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}
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if(i === L) C = (C>>>8) ^ T[(C ^ bstr.charCodeAt(i))&0xFF];
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return C ^ -1;
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}
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function crc32_buf(buf/*:ABuf*/)/*:CRC32Type*/ {
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if(buf.length > 10000) return crc32_buf_8(buf);
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var C = -1, L = buf.length - 3;
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for(var i = 0; i < L;) {
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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}
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while(i < L+3) C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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return C ^ -1;
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}
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function crc32_buf_8(buf/*:ABuf*/)/*:CRC32Type*/ {
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var C = -1, L = buf.length - 7;
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for(var i = 0; i < L;) {
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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}
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while(i < L+7) C = (C>>>8) ^ T[(C^buf[i++])&0xFF];
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return C ^ -1;
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}
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/*# much much faster to intertwine utf8 and C */
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function crc32_str(str/*:string*/)/*:CRC32Type*/ {
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var C = -1;
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for(var i = 0, L=str.length, c, d; i < L;) {
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c = str.charCodeAt(i++);
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if(c < 0x80) {
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C = (C>>>8) ^ T[(C ^ c)&0xFF];
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} else if(c < 0x800) {
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C = (C>>>8) ^ T[(C ^ (192|((c>>6)&31)))&0xFF];
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C = (C>>>8) ^ T[(C ^ (128|(c&63)))&0xFF];
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} else if(c >= 0xD800 && c < 0xE000) {
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c = (c&1023)+64; d = str.charCodeAt(i++)&1023;
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C = (C>>>8) ^ T[(C ^ (240|((c>>8)&7)))&0xFF];
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C = (C>>>8) ^ T[(C ^ (128|((c>>2)&63)))&0xFF];
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C = (C>>>8) ^ T[(C ^ (128|((d>>6)&15)|((c&3)<<4)))&0xFF];
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C = (C>>>8) ^ T[(C ^ (128|(d&63)))&0xFF];
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} else {
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C = (C>>>8) ^ T[(C ^ (224|((c>>12)&15)))&0xFF];
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C = (C>>>8) ^ T[(C ^ (128|((c>>6)&63)))&0xFF];
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C = (C>>>8) ^ T[(C ^ (128|(c&63)))&0xFF];
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}
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}
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return C ^ -1;
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}
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