diff options
Diffstat (limited to 'comm/chat/protocols/matrix/lib/base-x')
| -rw-r--r-- | comm/chat/protocols/matrix/lib/base-x/LICENSE.md | 22 | ||||
| -rw-r--r-- | comm/chat/protocols/matrix/lib/base-x/index.js | 119 |
2 files changed, 141 insertions, 0 deletions
diff --git a/comm/chat/protocols/matrix/lib/base-x/LICENSE.md b/comm/chat/protocols/matrix/lib/base-x/LICENSE.md new file mode 100644 index 0000000000..c5dca45542 --- /dev/null +++ b/comm/chat/protocols/matrix/lib/base-x/LICENSE.md @@ -0,0 +1,22 @@ +The MIT License (MIT) + +Copyright (c) 2018 base-x contributors +Copyright (c) 2014-2018 The Bitcoin Core developers + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. diff --git a/comm/chat/protocols/matrix/lib/base-x/index.js b/comm/chat/protocols/matrix/lib/base-x/index.js new file mode 100644 index 0000000000..5b695f1a4c --- /dev/null +++ b/comm/chat/protocols/matrix/lib/base-x/index.js @@ -0,0 +1,119 @@ +'use strict' +// base-x encoding / decoding +// Copyright (c) 2018 base-x contributors +// Copyright (c) 2014-2018 The Bitcoin Core developers (base58.cpp) +// Distributed under the MIT software license, see the accompanying +// file LICENSE or http://www.opensource.org/licenses/mit-license.php. +// @ts-ignore +var _Buffer = require('safe-buffer').Buffer +function base (ALPHABET) { + if (ALPHABET.length >= 255) { throw new TypeError('Alphabet too long') } + var BASE_MAP = new Uint8Array(256) + for (var j = 0; j < BASE_MAP.length; j++) { + BASE_MAP[j] = 255 + } + for (var i = 0; i < ALPHABET.length; i++) { + var x = ALPHABET.charAt(i) + var xc = x.charCodeAt(0) + if (BASE_MAP[xc] !== 255) { throw new TypeError(x + ' is ambiguous') } + BASE_MAP[xc] = i + } + var BASE = ALPHABET.length + var LEADER = ALPHABET.charAt(0) + var FACTOR = Math.log(BASE) / Math.log(256) // log(BASE) / log(256), rounded up + var iFACTOR = Math.log(256) / Math.log(BASE) // log(256) / log(BASE), rounded up + function encode (source) { + if (Array.isArray(source) || source instanceof Uint8Array) { source = _Buffer.from(source) } + if (!_Buffer.isBuffer(source)) { throw new TypeError('Expected Buffer') } + if (source.length === 0) { return '' } + // Skip & count leading zeroes. + var zeroes = 0 + var length = 0 + var pbegin = 0 + var pend = source.length + while (pbegin !== pend && source[pbegin] === 0) { + pbegin++ + zeroes++ + } + // Allocate enough space in big-endian base58 representation. + var size = ((pend - pbegin) * iFACTOR + 1) >>> 0 + var b58 = new Uint8Array(size) + // Process the bytes. + while (pbegin !== pend) { + var carry = source[pbegin] + // Apply "b58 = b58 * 256 + ch". + var i = 0 + for (var it1 = size - 1; (carry !== 0 || i < length) && (it1 !== -1); it1--, i++) { + carry += (256 * b58[it1]) >>> 0 + b58[it1] = (carry % BASE) >>> 0 + carry = (carry / BASE) >>> 0 + } + if (carry !== 0) { throw new Error('Non-zero carry') } + length = i + pbegin++ + } + // Skip leading zeroes in base58 result. + var it2 = size - length + while (it2 !== size && b58[it2] === 0) { + it2++ + } + // Translate the result into a string. + var str = LEADER.repeat(zeroes) + for (; it2 < size; ++it2) { str += ALPHABET.charAt(b58[it2]) } + return str + } + function decodeUnsafe (source) { + if (typeof source !== 'string') { throw new TypeError('Expected String') } + if (source.length === 0) { return _Buffer.alloc(0) } + var psz = 0 + // Skip and count leading '1's. + var zeroes = 0 + var length = 0 + while (source[psz] === LEADER) { + zeroes++ + psz++ + } + // Allocate enough space in big-endian base256 representation. + var size = (((source.length - psz) * FACTOR) + 1) >>> 0 // log(58) / log(256), rounded up. + var b256 = new Uint8Array(size) + // Process the characters. + while (source[psz]) { + // Decode character + var carry = BASE_MAP[source.charCodeAt(psz)] + // Invalid character + if (carry === 255) { return } + var i = 0 + for (var it3 = size - 1; (carry !== 0 || i < length) && (it3 !== -1); it3--, i++) { + carry += (BASE * b256[it3]) >>> 0 + b256[it3] = (carry % 256) >>> 0 + carry = (carry / 256) >>> 0 + } + if (carry !== 0) { throw new Error('Non-zero carry') } + length = i + psz++ + } + // Skip leading zeroes in b256. + var it4 = size - length + while (it4 !== size && b256[it4] === 0) { + it4++ + } + var vch = _Buffer.allocUnsafe(zeroes + (size - it4)) + vch.fill(0x00, 0, zeroes) + var j = zeroes + while (it4 !== size) { + vch[j++] = b256[it4++] + } + return vch + } + function decode (string) { + var buffer = decodeUnsafe(string) + if (buffer) { return buffer } + throw new Error('Non-base' + BASE + ' character') + } + return { + encode: encode, + decodeUnsafe: decodeUnsafe, + decode: decode + } +} +module.exports = base |