);
const { length } = u4s;
if (length % 2 == 1) {
+ // The length is such that an entire letter would be dropped during
+ // a forgiving decode.
throw new RangeError(
`Piscēs: Base16 string has invalid length: ${source}.`,
);
} else {
+ // Every letter contributes at least some bits to the result.
const dataView = new View(new Buffer(floor(length / 2)));
for (let index = 0; index < length - 1;) {
call(viewSetUint8, dataView, [
}
};
+/**
+ * Returns the result of decoding the provided base32 string into an
+ * ArrayBuffer.
+ *
+ * If the second argument is truthy, uses Crockford’s encoding rather
+ * than the RFC’s (see <https://www.crockford.com/base32.html>). This
+ * is more human‐friendly and tolerant. Check digits are not supported.
+ *
+ * ※ This function is not exposed.
+ */
+const decodeBase32 = (source, wrmg) => {
+ const u5s = map(
+ wrmg
+ ? stringReplace(source, /-/gu, "")
+ : source.length % 8 == 0
+ ? stringReplace(source, /(?:=|={3,4}|={6})$/u, "")
+ : source,
+ (ucsCharacter) => {
+ const code = getCodeUnit(ucsCharacter, 0);
+ const result = wrmg
+ ? code >= 0x30 && code <= 0x39
+ ? code - 48
+ : code >= 0x41 && code <= 0x48
+ ? code - 55
+ : code == 0x49
+ ? 1 // I
+ : code >= 0x4A && code <= 0x4B
+ ? code - 56
+ : code == 0x4C
+ ? 1 // L
+ : code >= 0x4D && code <= 0x4E
+ ? code - 57
+ : code == 0x4F
+ ? 0 // O
+ : code >= 0x50 && code <= 0x54
+ ? code - 58
+ // U is skipped
+ : code >= 0x56 && code <= 0x5A
+ ? code - 59
+ : code >= 0x61 && code <= 0x68
+ ? code - 87
+ : code == 0x69
+ ? 1 // i
+ : code >= 0x6A && code <= 0x6B
+ ? code - 88
+ : code == 0x6C
+ ? 1 // l
+ : code >= 0x6D && code <= 0x6E
+ ? code - 89
+ : code == 0x6F
+ ? 0 // o
+ : code >= 0x70 && code <= 0x74
+ ? code - 90
+ // u is skipped
+ : code >= 0x76 && code <= 0x7A
+ ? code - 91
+ : -1
+ : code >= 0x41 && code <= 0x5A
+ ? code - 65
+ : code >= 0x61 && code <= 0x7A
+ ? code - 97 // same result as above; case insensitive
+ : code >= 0x32 && code <= 0x37
+ ? code - 24 // digits 2–7 map to 26–31
+ : -1;
+ if (result < 0) {
+ throw new RangeError(
+ `Piscēs: Invalid character in Base32: ${ucsCharacter}.`,
+ );
+ } else {
+ return result;
+ }
+ },
+ );
+ const { length } = u5s;
+ const lengthMod8 = length % 8;
+ if (lengthMod8 == 1 || lengthMod8 == 3 || lengthMod8 == 6) {
+ // The length is such that an entire letter would be dropped during
+ // a forgiving decode.
+ throw new RangeError(
+ `Piscēs: Base32 string has invalid length: ${source}.`,
+ );
+ } else {
+ // Every letter contributes at least some bits to the result.
+ const dataView = new View(new Buffer(floor(length * 5 / 8)));
+ for (let index = 0; index < length - 1;) {
+ // The final index is not handled; if the string is not divisible
+ // by 8, some bits might be dropped. This matches the “forgiving
+ // decode” behaviour specified by WhatW·G for base64.
+ const dataIndex = ceil(index * 5 / 8);
+ const remainder = index % 8;
+ if (remainder == 0) {
+ call(viewSetUint8, dataView, [
+ dataIndex,
+ u5s[index] << 3 | u5s[++index] >> 2,
+ ]);
+ } else if (remainder == 1) {
+ call(viewSetUint8, dataView, [
+ dataIndex,
+ u5s[index] << 6 | u5s[++index] << 1 | u5s[++index] >> 4,
+ ]);
+ } else if (remainder == 3) {
+ call(viewSetUint8, dataView, [
+ dataIndex,
+ u5s[index] << 4 | u5s[++index] >> 1,
+ ]);
+ } else if (remainder == 4) {
+ call(viewSetUint8, dataView, [
+ dataIndex,
+ u5s[index] << 7 | u5s[++index] << 2 | u5s[++index] >> 3,
+ ]);
+ } else { // remainder == 6
+ call(viewSetUint8, dataView, [
+ dataIndex,
+ u5s[index] << 5 | u5s[++index, index++],
+ ]);
+ }
+ }
+ return call(getViewBuffer, dataView, []);
+ }
+};
+
/**
* Returns the result of decoding the provided base64 string into an
* ArrayBuffer.
);
const { length } = u6s;
if (length % 4 == 1) {
+ // The length is such that an entire letter would be dropped during
+ // a forgiving decode.
throw new RangeError(
`Piscēs: Base64 string has invalid length: ${source}.`,
);
} else {
+ // Every letter contributes at least some bits to the result.
const dataView = new View(new Buffer(floor(length * 3 / 4)));
for (let index = 0; index < length - 1;) {
// The final index is not handled; if the string is not divisible
return stringFromCodeUnits(...resultingCodeUnits);
};
+/**
+ * Returns the result of encoding the provided ArrayBuffer into a
+ * base32 string.
+ *
+ * ※ This function is not exposed.
+ */
+const encodeBase32 = (buffer, wrmg = false) => {
+ const dataView = new View(buffer);
+ const byteLength = call(getBufferByteLength, buffer, []);
+ const minimumLengthOfResults = ceil(byteLength * 8 / 5);
+ const fillByte = wrmg ? 0x2D : 0x3D;
+ const resultingCodeUnits = fill(
+ objectCreate(
+ binaryCodeUnitIterablePrototype,
+ {
+ length: {
+ value: minimumLengthOfResults +
+ (8 - (minimumLengthOfResults % 8)) % 8,
+ },
+ },
+ ),
+ fillByte,
+ );
+ for (let index = 0; index < byteLength;) {
+ const codeUnitIndex = ceil(index * 8 / 5);
+ const currentIndex = codeUnitIndex + +(
+ 0b01011 & 1 << index % 5 &&
+ resultingCodeUnits[codeUnitIndex] != fillByte
+ ); // bytes 0, 1 & 3 handle two letters; this is for the second
+ const remainder = currentIndex % 8;
+ const currentByte = call(viewGetUint8, dataView, [index]);
+ const nextByte =
+ 0b01011010 & 1 << remainder && ++index < byteLength
+ // digits 1, 3, 4 & 6 span multiple bytes
+ ? call(viewGetUint8, dataView, [index])
+ : 0;
+ const u5 = remainder == 0
+ ? currentByte >> 3
+ : remainder == 1
+ ? (currentByte & 0b00000111) << 2 | nextByte >> 6
+ : remainder == 2
+ ? (currentByte & 0b00111111) >> 1
+ : remainder == 3
+ ? (currentByte & 0b00000001) << 4 | nextByte >> 4
+ : remainder == 4
+ ? (currentByte & 0b00001111) << 1 | nextByte >> 7
+ : remainder == 5
+ ? (currentByte & 0b01111111) >> 2
+ : remainder == 6
+ ? (currentByte & 0b00000011) << 3 | nextByte >> 5
+ : (++index, currentByte & 0b00011111); // remainder == 7
+ const result = wrmg
+ ? u5 < 10 ? u5 + 48 : u5 < 18
+ ? u5 + 55
+ // skip I
+ : u5 < 20
+ ? u5 + 56
+ // skip L
+ : u5 < 22
+ ? u5 + 57
+ // skip O
+ : u5 < 27
+ ? u5 + 58
+ // skip U
+ : u5 < 32
+ ? u5 + 59
+ : -1
+ : u5 < 26
+ ? u5 + 65
+ : u5 < 32
+ ? u5 + 24
+ : -1;
+ if (result < 0) {
+ throw new RangeError(`Piscēs: Unexpected Base32 value: ${u5}.`);
+ } else {
+ resultingCodeUnits[currentIndex] = result;
+ }
+ }
+ const answer = stringFromCodeUnits(...resultingCodeUnits);
+ return wrmg ? answer.replace(/-+$/u, "") : answer;
+};
+
/**
* Returns the result of encoding the provided ArrayBuffer into a
* base64 string.
export const base16String = ($, ...$s) =>
encodeBase16(bufferFromArgs($, $s));
+/**
+ * Returns an ArrayBuffer generated from the provided base32 string.
+ *
+ * This function can also be used as a tag for a template literal. The
+ * literal will be interpreted akin to `String.raw`.
+ *
+ * ☡ This function throws if the provided string is not a valid base32
+ * string.
+ */
+export const base32Binary = ($, ...$s) =>
+ decodeBase32(sourceFromArgs($, $s));
+
+/**
+ * Returns a (big‐endian) base32 string created from the provided typed
+ * array, buffer, or (16‐bit) string.
+ *
+ * This function can also be used as a tag for a template literal. The
+ * literal will be interpreted akin to `String.raw`.
+ */
+export const base32String = ($, ...$s) =>
+ encodeBase32(bufferFromArgs($, $s));
+
/**
* Returns an ArrayBuffer generated from the provided base64 string.
*
}
};
+/**
+ * Returns whether the provided value is a base32 string.
+ *
+ * ※ This function returns false if the provided value is not a string
+ * primitive.
+ */
+export const isBase32 = ($) => {
+ if (typeof $ !== "string") {
+ return false;
+ } else {
+ const source = stringReplace($, /[\t\n\f\r ]+/gu, "");
+ const trimmed = source.length % 8 == 0
+ ? stringReplace(source, /(?:=|={3,4}|={6})$/u, "")
+ : source;
+ return trimmed.length % 8 != 1 &&
+ call(reExec, /[^2-7A-Z/]/iu, [trimmed]) == null;
+ }
+};
+
/**
* Returns whether the provided value is a Base64 string.
*
call(reExec, /[^0-9A-Za-z_-]/u, [trimmed]) == null;
}
};
+
+/**
+ * Returns whether the provided value is a W·R·M·G (Crockford) base32
+ * string. Check digits are not supported.
+ *
+ * ※ This function returns false if the provided value is not a string
+ * primitive.
+ */
+export const isWRMGBase32 = ($) => {
+ if (typeof $ !== "string") {
+ return false;
+ } else {
+ const source = stringReplace($, /[\t\n\f\r ]+/gu, "");
+ const trimmed = stringReplace(source, /-/gu, "");
+ return trimmed.length % 8 != 1 &&
+ call(reExec, /[^0-9A-TV-Z]/iu, [trimmed]) == null;
+ }
+};
+
+/**
+ * Returns an ArrayBuffer generated from the provided W·R·M·G
+ * (Crockford) base32 string.
+ *
+ * This function can also be used as a tag for a template literal. The
+ * literal will be interpreted akin to `String.raw`.
+ *
+ * ☡ This function throws if the provided string is not a valid W·R·M·G
+ * base32 string.
+ */
+export const wrmgBase32Binary = ($, ...$s) =>
+ decodeBase32(sourceFromArgs($, $s), true);
+
+/**
+ * Returns a (big‐endian) W·R·M·G (Crockford) base32 string created
+ * from the provided typed array, buffer, or (16‐bit) string.
+ *
+ * This function can also be used as a tag for a template literal. The
+ * literal will be interpreted akin to `String.raw`.
+ */
+export const wrmgBase32String = ($, ...$s) =>
+ encodeBase32(bufferFromArgs($, $s), true);
Lady’s Gitweb / Pisces / blobdiff