xref: /aosp_15_r20/development/tools/winscope/src/parsers/legacy/parsing_utils.ts (revision 90c8c64db3049935a07c6143d7fd006e26f8ecca)
1/*
2 * Copyright (C) 2023 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17import {ArrayUtils} from 'common/array_utils';
18
19export class ParsingUtils {
20  static throwIfMagicNumberDoesNotMatch(
21    traceBuffer: Uint8Array,
22    magicNumber: number[] | undefined,
23  ) {
24    if (magicNumber !== undefined) {
25      const bufferContainsMagicNumber = ArrayUtils.equal(
26        magicNumber,
27        traceBuffer.slice(0, magicNumber.length),
28      );
29      if (!bufferContainsMagicNumber) {
30        throw new TypeError("buffer doesn't contain expected magic number");
31      }
32    }
33  }
34}
35