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-rw-r--r--node_modules/base64-js/index.js150
1 files changed, 150 insertions, 0 deletions
diff --git a/node_modules/base64-js/index.js b/node_modules/base64-js/index.js
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+++ b/node_modules/base64-js/index.js
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+'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('')
+}