43 lines
1.3 KiB
JavaScript
43 lines
1.3 KiB
JavaScript
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"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.isUtf8 = void 0;
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const isUtf8 = (buf, from, length) => {
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const to = from + length;
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while (from < to) {
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const c = buf[from];
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if (c <= 0x7f) {
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from++;
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continue;
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}
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if (c >= 0xc2 && c <= 0xdf) {
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if (buf[from + 1] >> 6 === 2) {
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from += 2;
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continue;
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}
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else
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return false;
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}
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const c1 = buf[from + 1];
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if (((c === 0xe0 && c1 >= 0xa0 && c1 <= 0xbf) || (c === 0xed && c1 >= 0x80 && c1 <= 0x9f)) &&
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buf[from + 2] >> 6 === 2) {
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from += 3;
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continue;
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}
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if (((c >= 0xe1 && c <= 0xec) || (c >= 0xee && c <= 0xef)) && c1 >> 6 === 2 && buf[from + 2] >> 6 === 2) {
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from += 3;
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continue;
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}
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if (((c === 0xf0 && c1 >= 0x90 && c1 <= 0xbf) ||
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(c >= 0xf1 && c <= 0xf3 && c1 >> 6 === 2) ||
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(c === 0xf4 && c1 >= 0x80 && c1 <= 0x8f)) &&
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buf[from + 2] >> 6 === 2 &&
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buf[from + 3] >> 6 === 2) {
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from += 4;
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continue;
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}
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return false;
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}
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return true;
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};
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exports.isUtf8 = isUtf8;
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//# sourceMappingURL=isUtf8.js.map
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