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lnked/base64.js

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Created January 5, 2023 17:27
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  1. @enepomnyaschih enepomnyaschih revised this gist Jun 1, 2020. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion base64.js
    View file
    Original file line number Diff line number Diff line change
    @@ -71,7 +71,7 @@ const base64codes = [
    ];

    function getBase64Code(charCode) {
    if (charCode > base64codes.length) {
    if (charCode >= base64codes.length) {
    throw new Error("Unable to parse base64 string.");
    }
    const code = base64codes[charCode];
  2. @enepomnyaschih enepomnyaschih revised this gist Apr 12, 2020. 1 changed file with 77 additions and 37 deletions.
    114 changes: 77 additions & 37 deletions base64.js
    View file
    Original file line number Diff line number Diff line change
    @@ -1,33 +1,74 @@
    const base64abc = (() => {
    const abc = [],
    A = "A".charCodeAt(0),
    a = "a".charCodeAt(0),
    n = "0".charCodeAt(0);
    for (let i = 0; i < 26; ++i) {
    abc.push(String.fromCharCode(A + i));
    }
    for (let i = 0; i < 26; ++i) {
    abc.push(String.fromCharCode(a + i));
    }
    for (let i = 0; i < 10; ++i) {
    abc.push(String.fromCharCode(n + i));
    }
    abc.push("+");
    abc.push("/");
    return abc;
    })();
    /*
    MIT License
    const base64codes = (() => {
    const l = 256, codes = new Uint8Array(l);
    for (let i = 0; i < l; ++i) {
    codes[i] = 255; // invalid character
    }
    base64abc.forEach((char, index) => {
    codes[char.charCodeAt(0)] = index;
    });
    codes["=".charCodeAt(0)] = 0; // ignored anyway, so we just need to prevent an error
    return codes;
    })();
    Copyright (c) 2020 Egor Nepomnyaschih
    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.
    */

    /*
    // This constant can also be computed with the following algorithm:
    const base64abc = [],
    A = "A".charCodeAt(0),
    a = "a".charCodeAt(0),
    n = "0".charCodeAt(0);
    for (let i = 0; i < 26; ++i) {
    base64abc.push(String.fromCharCode(A + i));
    }
    for (let i = 0; i < 26; ++i) {
    base64abc.push(String.fromCharCode(a + i));
    }
    for (let i = 0; i < 10; ++i) {
    base64abc.push(String.fromCharCode(n + i));
    }
    base64abc.push("+");
    base64abc.push("/");
    */
    const base64abc = [
    "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M",
    "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z",
    "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
    "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z",
    "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "+", "/"
    ];

    /*
    // This constant can also be computed with the following algorithm:
    const l = 256, base64codes = new Uint8Array(l);
    for (let i = 0; i < l; ++i) {
    base64codes[i] = 255; // invalid character
    }
    base64abc.forEach((char, index) => {
    base64codes[char.charCodeAt(0)] = index;
    });
    base64codes["=".charCodeAt(0)] = 0; // ignored anyway, so we just need to prevent an error
    */
    const base64codes = [
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 62, 255, 255, 255, 63,
    52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 255, 255, 255, 0, 255, 255,
    255, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
    15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 255, 255, 255, 255, 255,
    255, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
    41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51
    ];

    function getBase64Code(charCode) {
    if (charCode > base64codes.length) {
    @@ -66,6 +107,10 @@ export function base64ToBytes(str) {
    if (str.length % 4 !== 0) {
    throw new Error("Unable to parse base64 string.");
    }
    const index = str.indexOf("=");
    if (index !== -1 && index < str.length - 2) {
    throw new Error("Unable to parse base64 string.");
    }
    let missingOctets = str.endsWith("==") ? 2 : str.endsWith("=") ? 1 : 0,
    n = str.length,
    result = new Uint8Array(3 * (n / 4)),
    @@ -83,15 +128,10 @@ export function base64ToBytes(str) {
    return result.subarray(0, result.length - missingOctets);
    }

    const utf8encoder = new TextEncoder(),
    utf8decoder = new TextDecoder();

    // All solutions at MDN only provide a way to encode a native JS string to UTF-16 base64 string.
    // Here, you can apply any encoding supported by TextEncoder.
    export function base64encode(str, encoder = utf8encoder) {
    export function base64encode(str, encoder = new TextEncoder()) {
    return bytesToBase64(encoder.encode(str));
    }

    export function base64decode(str, decoder = utf8decoder) {
    export function base64decode(str, decoder = new TextDecoder()) {
    return decoder.decode(base64ToBytes(str));
    }
    }
  3. @enepomnyaschih enepomnyaschih revised this gist Apr 12, 2020. No changes.
  4. @enepomnyaschih enepomnyaschih revised this gist Apr 12, 2020. 1 changed file with 56 additions and 7 deletions.
    63 changes: 56 additions & 7 deletions base64.js
    View file
    Original file line number Diff line number Diff line change
    @@ -1,5 +1,5 @@
    const base64abc = (() => {
    let abc = [],
    const abc = [],
    A = "A".charCodeAt(0),
    a = "a".charCodeAt(0),
    n = "0".charCodeAt(0);
    @@ -17,20 +17,43 @@ const base64abc = (() => {
    return abc;
    })();

    function bytesToBase64(bytes) {
    const base64codes = (() => {
    const l = 256, codes = new Uint8Array(l);
    for (let i = 0; i < l; ++i) {
    codes[i] = 255; // invalid character
    }
    base64abc.forEach((char, index) => {
    codes[char.charCodeAt(0)] = index;
    });
    codes["=".charCodeAt(0)] = 0; // ignored anyway, so we just need to prevent an error
    return codes;
    })();

    function getBase64Code(charCode) {
    if (charCode > base64codes.length) {
    throw new Error("Unable to parse base64 string.");
    }
    const code = base64codes[charCode];
    if (code === 255) {
    throw new Error("Unable to parse base64 string.");
    }
    return code;
    }

    export function bytesToBase64(bytes) {
    let result = '', i, l = bytes.length;
    for (i = 2; i < l; i += 3) {
    result += base64abc[bytes[i - 2] >> 2];
    result += base64abc[((bytes[i - 2] & 0x03) << 4) | (bytes[i - 1] >> 4)];
    result += base64abc[((bytes[i - 1] & 0x0F) << 2) | (bytes[i] >> 6)];
    result += base64abc[bytes[i] & 0x3F];
    }
    if (i === l + 1) { // 1 octet missing
    if (i === l + 1) { // 1 octet yet to write
    result += base64abc[bytes[i - 2] >> 2];
    result += base64abc[(bytes[i - 2] & 0x03) << 4];
    result += "==";
    }
    if (i === l) { // 2 octets missing
    if (i === l) { // 2 octets yet to write
    result += base64abc[bytes[i - 2] >> 2];
    result += base64abc[((bytes[i - 2] & 0x03) << 4) | (bytes[i - 1] >> 4)];
    result += base64abc[(bytes[i - 1] & 0x0F) << 2];
    @@ -39,10 +62,36 @@ function bytesToBase64(bytes) {
    return result;
    }

    const utf8encoder = new TextEncoder();
    export function base64ToBytes(str) {
    if (str.length % 4 !== 0) {
    throw new Error("Unable to parse base64 string.");
    }
    let missingOctets = str.endsWith("==") ? 2 : str.endsWith("=") ? 1 : 0,
    n = str.length,
    result = new Uint8Array(3 * (n / 4)),
    buffer;
    for (let i = 0, j = 0; i < n; i += 4, j += 3) {
    buffer =
    getBase64Code(str.charCodeAt(i)) << 18 |
    getBase64Code(str.charCodeAt(i + 1)) << 12 |
    getBase64Code(str.charCodeAt(i + 2)) << 6 |
    getBase64Code(str.charCodeAt(i + 3));
    result[j] = buffer >> 16;
    result[j + 1] = (buffer >> 8) & 0xFF;
    result[j + 2] = buffer & 0xFF;
    }
    return result.subarray(0, result.length - missingOctets);
    }

    const utf8encoder = new TextEncoder(),
    utf8decoder = new TextDecoder();

    // All solutions at MDN only provide a way to encode a native JS string to UTF-16 base64 string.
    // Here, you can apply any encoding supported by TextEncoder.
    function base64utf8encode(str) {
    return bytesToBase64(utf8encoder.encode(str));
    export function base64encode(str, encoder = utf8encoder) {
    return bytesToBase64(encoder.encode(str));
    }

    export function base64decode(str, decoder = utf8decoder) {
    return decoder.decode(base64ToBytes(str));
    }
  5. @enepomnyaschih enepomnyaschih renamed this gist Jul 19, 2019. 1 changed file with 0 additions and 0 deletions.
    0 gistfile1.txt → base64.js
    View file
    File renamed without changes.
  6. @enepomnyaschih enepomnyaschih revised this gist Jul 19, 2019. 1 changed file with 8 additions and 0 deletions.
    8 changes: 8 additions & 0 deletions gistfile1.txt
    View file
    Original file line number Diff line number Diff line change
    @@ -38,3 +38,11 @@ function bytesToBase64(bytes) {
    }
    return result;
    }

    const utf8encoder = new TextEncoder();

    // All solutions at MDN only provide a way to encode a native JS string to UTF-16 base64 string.
    // Here, you can apply any encoding supported by TextEncoder.
    function base64utf8encode(str) {
    return bytesToBase64(utf8encoder.encode(str));
    }
  7. @enepomnyaschih enepomnyaschih created this gist Jul 19, 2019.
    40 changes: 40 additions & 0 deletions gistfile1.txt
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,40 @@
    const base64abc = (() => {
    let abc = [],
    A = "A".charCodeAt(0),
    a = "a".charCodeAt(0),
    n = "0".charCodeAt(0);
    for (let i = 0; i < 26; ++i) {
    abc.push(String.fromCharCode(A + i));
    }
    for (let i = 0; i < 26; ++i) {
    abc.push(String.fromCharCode(a + i));
    }
    for (let i = 0; i < 10; ++i) {
    abc.push(String.fromCharCode(n + i));
    }
    abc.push("+");
    abc.push("/");
    return abc;
    })();

    function bytesToBase64(bytes) {
    let result = '', i, l = bytes.length;
    for (i = 2; i < l; i += 3) {
    result += base64abc[bytes[i - 2] >> 2];
    result += base64abc[((bytes[i - 2] & 0x03) << 4) | (bytes[i - 1] >> 4)];
    result += base64abc[((bytes[i - 1] & 0x0F) << 2) | (bytes[i] >> 6)];
    result += base64abc[bytes[i] & 0x3F];
    }
    if (i === l + 1) { // 1 octet missing
    result += base64abc[bytes[i - 2] >> 2];
    result += base64abc[(bytes[i - 2] & 0x03) << 4];
    result += "==";
    }
    if (i === l) { // 2 octets missing
    result += base64abc[bytes[i - 2] >> 2];
    result += base64abc[((bytes[i - 2] & 0x03) << 4) | (bytes[i - 1] >> 4)];
    result += base64abc[(bytes[i - 1] & 0x0F) << 2];
    result += "=";
    }
    return result;
    }