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-rw-r--r--node_modules/source-map/lib/base64.js67
1 files changed, 67 insertions, 0 deletions
diff --git a/node_modules/source-map/lib/base64.js b/node_modules/source-map/lib/base64.js
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+++ b/node_modules/source-map/lib/base64.js
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+/* -*- Mode: js; js-indent-level: 2; -*- */
+/*
+ * Copyright 2011 Mozilla Foundation and contributors
+ * Licensed under the New BSD license. See LICENSE or:
+ * http://opensource.org/licenses/BSD-3-Clause
+ */
+
+var intToCharMap = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'.split('');
+
+/**
+ * Encode an integer in the range of 0 to 63 to a single base 64 digit.
+ */
+exports.encode = function (number) {
+ if (0 <= number && number < intToCharMap.length) {
+ return intToCharMap[number];
+ }
+ throw new TypeError("Must be between 0 and 63: " + number);
+};
+
+/**
+ * Decode a single base 64 character code digit to an integer. Returns -1 on
+ * failure.
+ */
+exports.decode = function (charCode) {
+ var bigA = 65; // 'A'
+ var bigZ = 90; // 'Z'
+
+ var littleA = 97; // 'a'
+ var littleZ = 122; // 'z'
+
+ var zero = 48; // '0'
+ var nine = 57; // '9'
+
+ var plus = 43; // '+'
+ var slash = 47; // '/'
+
+ var littleOffset = 26;
+ var numberOffset = 52;
+
+ // 0 - 25: ABCDEFGHIJKLMNOPQRSTUVWXYZ
+ if (bigA <= charCode && charCode <= bigZ) {
+ return (charCode - bigA);
+ }
+
+ // 26 - 51: abcdefghijklmnopqrstuvwxyz
+ if (littleA <= charCode && charCode <= littleZ) {
+ return (charCode - littleA + littleOffset);
+ }
+
+ // 52 - 61: 0123456789
+ if (zero <= charCode && charCode <= nine) {
+ return (charCode - zero + numberOffset);
+ }
+
+ // 62: +
+ if (charCode == plus) {
+ return 62;
+ }
+
+ // 63: /
+ if (charCode == slash) {
+ return 63;
+ }
+
+ // Invalid base64 digit.
+ return -1;
+};