3624f9eac7
Given that the `bytesToString(BaseStream.getBytes(...))` pattern is somewhat common throughout the `src/core/` code, it cannot hurt to add a new `BaseStream`-method which handles that case internally.
111 lines
2.5 KiB
JavaScript
111 lines
2.5 KiB
JavaScript
/* Copyright 2021 Mozilla Foundation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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import { bytesToString, shadow, unreachable } from "../shared/util.js";
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class BaseStream {
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constructor() {
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if (this.constructor === BaseStream) {
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unreachable("Cannot initialize BaseStream.");
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}
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}
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// eslint-disable-next-line getter-return
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get length() {
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unreachable("Abstract getter `length` accessed");
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}
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// eslint-disable-next-line getter-return
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get isEmpty() {
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unreachable("Abstract getter `isEmpty` accessed");
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}
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get isDataLoaded() {
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return shadow(this, "isDataLoaded", true);
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}
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getByte() {
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unreachable("Abstract method `getByte` called");
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}
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getBytes(length, forceClamped = false) {
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unreachable("Abstract method `getBytes` called");
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}
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peekByte() {
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const peekedByte = this.getByte();
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if (peekedByte !== -1) {
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this.pos--;
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}
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return peekedByte;
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}
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peekBytes(length, forceClamped = false) {
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const bytes = this.getBytes(length, forceClamped);
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this.pos -= bytes.length;
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return bytes;
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}
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getUint16() {
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const b0 = this.getByte();
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const b1 = this.getByte();
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if (b0 === -1 || b1 === -1) {
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return -1;
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}
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return (b0 << 8) + b1;
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}
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getInt32() {
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const b0 = this.getByte();
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const b1 = this.getByte();
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const b2 = this.getByte();
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const b3 = this.getByte();
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return (b0 << 24) + (b1 << 16) + (b2 << 8) + b3;
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}
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getByteRange(begin, end) {
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unreachable("Abstract method `getByteRange` called");
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}
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getString(length) {
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return bytesToString(this.getBytes(length, /* forceClamped = */ false));
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}
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skip(n) {
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this.pos += n || 1;
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}
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reset() {
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unreachable("Abstract method `reset` called");
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}
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moveStart() {
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unreachable("Abstract method `moveStart` called");
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}
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makeSubStream(start, length, dict = null) {
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unreachable("Abstract method `makeSubStream` called");
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}
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/**
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* @returns {Array | null}
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*/
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getBaseStreams() {
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return null;
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}
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}
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export { BaseStream };
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