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Commit Description:
temporary for logo voting
Commit Description:
temporary for logo voting
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node_modules/base64-js/index.js
| 152 lines
| 3.9 KiB
| application/javascript
| JavascriptLexer
|
r789 | 'use strict' | |||
exports.byteLength = byteLength | ||||
exports.toByteArray = toByteArray | ||||
exports.fromByteArray = fromByteArray | ||||
var lookup = [] | ||||
var revLookup = [] | ||||
var Arr = typeof Uint8Array !== 'undefined' ? Uint8Array : Array | ||||
var code = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/' | ||||
for (var i = 0, len = code.length; i < len; ++i) { | ||||
lookup[i] = code[i] | ||||
revLookup[code.charCodeAt(i)] = i | ||||
} | ||||
// Support decoding URL-safe base64 strings, as Node.js does. | ||||
// See: https://en.wikipedia.org/wiki/Base64#URL_applications | ||||
revLookup['-'.charCodeAt(0)] = 62 | ||||
revLookup['_'.charCodeAt(0)] = 63 | ||||
function getLens (b64) { | ||||
var len = b64.length | ||||
if (len % 4 > 0) { | ||||
throw new Error('Invalid string. Length must be a multiple of 4') | ||||
} | ||||
// Trim off extra bytes after placeholder bytes are found | ||||
// See: https://github.com/beatgammit/base64-js/issues/42 | ||||
var validLen = b64.indexOf('=') | ||||
if (validLen === -1) validLen = len | ||||
var placeHoldersLen = validLen === len | ||||
? 0 | ||||
: 4 - (validLen % 4) | ||||
return [validLen, placeHoldersLen] | ||||
} | ||||
// base64 is 4/3 + up to two characters of the original data | ||||
function byteLength (b64) { | ||||
var lens = getLens(b64) | ||||
var validLen = lens[0] | ||||
var placeHoldersLen = lens[1] | ||||
return ((validLen + placeHoldersLen) * 3 / 4) - placeHoldersLen | ||||
} | ||||
function _byteLength (b64, validLen, placeHoldersLen) { | ||||
return ((validLen + placeHoldersLen) * 3 / 4) - placeHoldersLen | ||||
} | ||||
function toByteArray (b64) { | ||||
var tmp | ||||
var lens = getLens(b64) | ||||
var validLen = lens[0] | ||||
var placeHoldersLen = lens[1] | ||||
var arr = new Arr(_byteLength(b64, validLen, placeHoldersLen)) | ||||
var curByte = 0 | ||||
// if there are placeholders, only get up to the last complete 4 chars | ||||
var len = placeHoldersLen > 0 | ||||
? validLen - 4 | ||||
: validLen | ||||
var i | ||||
for (i = 0; i < len; i += 4) { | ||||
tmp = | ||||
(revLookup[b64.charCodeAt(i)] << 18) | | ||||
(revLookup[b64.charCodeAt(i + 1)] << 12) | | ||||
(revLookup[b64.charCodeAt(i + 2)] << 6) | | ||||
revLookup[b64.charCodeAt(i + 3)] | ||||
arr[curByte++] = (tmp >> 16) & 0xFF | ||||
arr[curByte++] = (tmp >> 8) & 0xFF | ||||
arr[curByte++] = tmp & 0xFF | ||||
} | ||||
if (placeHoldersLen === 2) { | ||||
tmp = | ||||
(revLookup[b64.charCodeAt(i)] << 2) | | ||||
(revLookup[b64.charCodeAt(i + 1)] >> 4) | ||||
arr[curByte++] = tmp & 0xFF | ||||
} | ||||
if (placeHoldersLen === 1) { | ||||
tmp = | ||||
(revLookup[b64.charCodeAt(i)] << 10) | | ||||
(revLookup[b64.charCodeAt(i + 1)] << 4) | | ||||
(revLookup[b64.charCodeAt(i + 2)] >> 2) | ||||
arr[curByte++] = (tmp >> 8) & 0xFF | ||||
arr[curByte++] = tmp & 0xFF | ||||
} | ||||
return arr | ||||
} | ||||
function tripletToBase64 (num) { | ||||
return lookup[num >> 18 & 0x3F] + | ||||
lookup[num >> 12 & 0x3F] + | ||||
lookup[num >> 6 & 0x3F] + | ||||
lookup[num & 0x3F] | ||||
} | ||||
function encodeChunk (uint8, start, end) { | ||||
var tmp | ||||
var output = [] | ||||
for (var i = start; i < end; i += 3) { | ||||
tmp = | ||||
((uint8[i] << 16) & 0xFF0000) + | ||||
((uint8[i + 1] << 8) & 0xFF00) + | ||||
(uint8[i + 2] & 0xFF) | ||||
output.push(tripletToBase64(tmp)) | ||||
} | ||||
return output.join('') | ||||
} | ||||
function fromByteArray (uint8) { | ||||
var tmp | ||||
var len = uint8.length | ||||
var extraBytes = len % 3 // if we have 1 byte left, pad 2 bytes | ||||
var parts = [] | ||||
var maxChunkLength = 16383 // must be multiple of 3 | ||||
// go through the array every three bytes, we'll deal with trailing stuff later | ||||
for (var i = 0, len2 = len - extraBytes; i < len2; i += maxChunkLength) { | ||||
parts.push(encodeChunk( | ||||
uint8, i, (i + maxChunkLength) > len2 ? len2 : (i + maxChunkLength) | ||||
)) | ||||
} | ||||
// pad the end with zeros, but make sure to not forget the extra bytes | ||||
if (extraBytes === 1) { | ||||
tmp = uint8[len - 1] | ||||
parts.push( | ||||
lookup[tmp >> 2] + | ||||
lookup[(tmp << 4) & 0x3F] + | ||||
'==' | ||||
) | ||||
} else if (extraBytes === 2) { | ||||
tmp = (uint8[len - 2] << 8) + uint8[len - 1] | ||||
parts.push( | ||||
lookup[tmp >> 10] + | ||||
lookup[(tmp >> 4) & 0x3F] + | ||||
lookup[(tmp << 2) & 0x3F] + | ||||
'=' | ||||
) | ||||
} | ||||
return parts.join('') | ||||
} | ||||