slige/web/public/dist/bytes.esm.js

319 lines
7.6 KiB
JavaScript

// https://deno.land/std@0.185.0/bytes/bytes_list.ts
var BytesList = class {
#len = 0;
#chunks = [];
constructor() {
}
/**
* Total size of bytes
*/
size() {
return this.#len;
}
/**
* Push bytes with given offset infos
*/
add(value, start = 0, end = value.byteLength) {
if (value.byteLength === 0 || end - start === 0) {
return;
}
checkRange(start, end, value.byteLength);
this.#chunks.push({
value,
end,
start,
offset: this.#len
});
this.#len += end - start;
}
/**
* Drop head `n` bytes.
*/
shift(n) {
if (n === 0) {
return;
}
if (this.#len <= n) {
this.#chunks = [];
this.#len = 0;
return;
}
const idx = this.getChunkIndex(n);
this.#chunks.splice(0, idx);
const [chunk] = this.#chunks;
if (chunk) {
const diff = n - chunk.offset;
chunk.start += diff;
}
let offset = 0;
for (const chunk2 of this.#chunks) {
chunk2.offset = offset;
offset += chunk2.end - chunk2.start;
}
this.#len = offset;
}
/**
* Find chunk index in which `pos` locates by binary-search
* returns -1 if out of range
*/
getChunkIndex(pos) {
let max = this.#chunks.length;
let min = 0;
while (true) {
const i = min + Math.floor((max - min) / 2);
if (i < 0 || this.#chunks.length <= i) {
return -1;
}
const { offset, start, end } = this.#chunks[i];
const len = end - start;
if (offset <= pos && pos < offset + len) {
return i;
} else if (offset + len <= pos) {
min = i + 1;
} else {
max = i - 1;
}
}
}
/**
* Get indexed byte from chunks
*/
get(i) {
if (i < 0 || this.#len <= i) {
throw new Error("out of range");
}
const idx = this.getChunkIndex(i);
const { value, offset, start } = this.#chunks[idx];
return value[start + i - offset];
}
/**
* Iterator of bytes from given position
*/
*iterator(start = 0) {
const startIdx = this.getChunkIndex(start);
if (startIdx < 0)
return;
const first = this.#chunks[startIdx];
let firstOffset = start - first.offset;
for (let i = startIdx; i < this.#chunks.length; i++) {
const chunk = this.#chunks[i];
for (let j = chunk.start + firstOffset; j < chunk.end; j++) {
yield chunk.value[j];
}
firstOffset = 0;
}
}
/**
* Returns subset of bytes copied
*/
slice(start, end = this.#len) {
if (end === start) {
return new Uint8Array();
}
checkRange(start, end, this.#len);
const result = new Uint8Array(end - start);
const startIdx = this.getChunkIndex(start);
const endIdx = this.getChunkIndex(end - 1);
let written = 0;
for (let i = startIdx; i <= endIdx; i++) {
const {
value: chunkValue,
start: chunkStart,
end: chunkEnd,
offset: chunkOffset
} = this.#chunks[i];
const readStart = chunkStart + (i === startIdx ? start - chunkOffset : 0);
const readEnd = i === endIdx ? end - chunkOffset + chunkStart : chunkEnd;
const len = readEnd - readStart;
result.set(chunkValue.subarray(readStart, readEnd), written);
written += len;
}
return result;
}
/**
* Concatenate chunks into single Uint8Array copied.
*/
concat() {
const result = new Uint8Array(this.#len);
let sum = 0;
for (const { value, start, end } of this.#chunks) {
result.set(value.subarray(start, end), sum);
sum += end - start;
}
return result;
}
};
function checkRange(start, end, len) {
if (start < 0 || len < start || end < 0 || len < end || end < start) {
throw new Error("invalid range");
}
}
// https://deno.land/std@0.185.0/bytes/concat.ts
function concat(...buf) {
let length = 0;
for (const b of buf) {
length += b.length;
}
const output = new Uint8Array(length);
let index = 0;
for (const b of buf) {
output.set(b, index);
index += b.length;
}
return output;
}
// https://deno.land/std@0.185.0/bytes/copy.ts
function copy(src, dst, off = 0) {
off = Math.max(0, Math.min(off, dst.byteLength));
const dstBytesAvailable = dst.byteLength - off;
if (src.byteLength > dstBytesAvailable) {
src = src.subarray(0, dstBytesAvailable);
}
dst.set(src, off);
return src.byteLength;
}
// https://deno.land/std@0.185.0/bytes/ends_with.ts
function endsWith(source, suffix) {
for (let srci = source.length - 1, sfxi = suffix.length - 1; sfxi >= 0; srci--, sfxi--) {
if (source[srci] !== suffix[sfxi])
return false;
}
return true;
}
// https://deno.land/std@0.185.0/bytes/equals.ts
function equalsNaive(a, b) {
for (let i = 0; i < b.length; i++) {
if (a[i] !== b[i])
return false;
}
return true;
}
function equals32Bit(a, b) {
const len = a.length;
const compressable = Math.floor(len / 4);
const compressedA = new Uint32Array(a.buffer, 0, compressable);
const compressedB = new Uint32Array(b.buffer, 0, compressable);
for (let i = compressable * 4; i < len; i++) {
if (a[i] !== b[i])
return false;
}
for (let i = 0; i < compressedA.length; i++) {
if (compressedA[i] !== compressedB[i])
return false;
}
return true;
}
function equals(a, b) {
if (a.length !== b.length) {
return false;
}
return a.length < 1e3 ? equalsNaive(a, b) : equals32Bit(a, b);
}
// https://deno.land/std@0.185.0/bytes/index_of_needle.ts
function indexOfNeedle(source, needle, start = 0) {
if (start >= source.length) {
return -1;
}
if (start < 0) {
start = Math.max(0, source.length + start);
}
const s = needle[0];
for (let i = start; i < source.length; i++) {
if (source[i] !== s)
continue;
const pin = i;
let matched = 1;
let j = i;
while (matched < needle.length) {
j++;
if (source[j] !== needle[j - pin]) {
break;
}
matched++;
}
if (matched === needle.length) {
return pin;
}
}
return -1;
}
// https://deno.land/std@0.185.0/bytes/includes_needle.ts
function includesNeedle(source, needle, start = 0) {
return indexOfNeedle(source, needle, start) !== -1;
}
// https://deno.land/std@0.185.0/bytes/last_index_of_needle.ts
function lastIndexOfNeedle(source, needle, start = source.length - 1) {
if (start < 0) {
return -1;
}
if (start >= source.length) {
start = source.length - 1;
}
const e = needle[needle.length - 1];
for (let i = start; i >= 0; i--) {
if (source[i] !== e)
continue;
const pin = i;
let matched = 1;
let j = i;
while (matched < needle.length) {
j--;
if (source[j] !== needle[needle.length - 1 - (pin - j)]) {
break;
}
matched++;
}
if (matched === needle.length) {
return pin - needle.length + 1;
}
}
return -1;
}
// https://deno.land/std@0.185.0/bytes/repeat.ts
function repeat(source, count) {
if (count === 0) {
return new Uint8Array();
}
if (count < 0) {
throw new RangeError("bytes: negative repeat count");
}
if (!Number.isInteger(count)) {
throw new Error("bytes: repeat count must be an integer");
}
const nb = new Uint8Array(source.length * count);
let bp = copy(source, nb);
for (; bp < nb.length; bp *= 2) {
copy(nb.slice(0, bp), nb, bp);
}
return nb;
}
// https://deno.land/std@0.185.0/bytes/starts_with.ts
function startsWith(source, prefix) {
for (let i = 0, max = prefix.length; i < max; i++) {
if (source[i] !== prefix[i])
return false;
}
return true;
}
export {
BytesList,
concat,
copy,
endsWith,
equals,
includesNeedle,
indexOfNeedle,
lastIndexOfNeedle,
repeat,
startsWith
};