46 lines
1.4 KiB
JavaScript
46 lines
1.4 KiB
JavaScript
export class ByteQueue {
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#array;
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#shiftPos;
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#pushPos;
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constructor(initialCap) {
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this.#array = new Uint8Array(new ArrayBuffer(initialCap));
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this.#shiftPos = 0;
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this.#pushPos = 0;
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}
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get length() {
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return this.#pushPos - this.#shiftPos;
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}
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data() {
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return this.#array.slice(this.#shiftPos, this.#pushPos);
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}
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push(chunk) {
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this.#ensurePush(chunk.byteLength);
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this.#array.set(chunk, this.#pushPos);
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this.#pushPos += chunk.byteLength;
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}
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#ensurePush(pushLength) {
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if (this.#pushPos + pushLength <= this.#array.byteLength) {
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return;
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}
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const filledLength = this.#pushPos - this.#shiftPos;
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if (filledLength + pushLength <= this.#array.byteLength &&
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2 * this.#pushPos >= this.#array.byteLength) {
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this.#array.copyWithin(0, this.#shiftPos, this.#pushPos);
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}
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else {
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let newCap = this.#array.byteLength;
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do {
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newCap *= 2;
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} while (filledLength + pushLength > newCap);
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const newArray = new Uint8Array(new ArrayBuffer(newCap));
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newArray.set(this.#array.slice(this.#shiftPos, this.#pushPos), 0);
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this.#array = newArray;
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}
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this.#pushPos = filledLength;
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this.#shiftPos = 0;
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}
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shift(length) {
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this.#shiftPos += length;
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}
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}
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