xref: /aosp_15_r20/external/perfetto/ui/src/base/hash.ts (revision 6dbdd20afdafa5e3ca9b8809fa73465d530080dc)
1*6dbdd20aSAndroid Build Coastguard Worker// Copyright (C) 2023 The Android Open Source Project
2*6dbdd20aSAndroid Build Coastguard Worker//
3*6dbdd20aSAndroid Build Coastguard Worker// Licensed under the Apache License, Version 2.0 (the "License");
4*6dbdd20aSAndroid Build Coastguard Worker// you may not use this file except in compliance with the License.
5*6dbdd20aSAndroid Build Coastguard Worker// You may obtain a copy of the License at
6*6dbdd20aSAndroid Build Coastguard Worker//
7*6dbdd20aSAndroid Build Coastguard Worker//      http://www.apache.org/licenses/LICENSE-2.0
8*6dbdd20aSAndroid Build Coastguard Worker//
9*6dbdd20aSAndroid Build Coastguard Worker// Unless required by applicable law or agreed to in writing, software
10*6dbdd20aSAndroid Build Coastguard Worker// distributed under the License is distributed on an "AS IS" BASIS,
11*6dbdd20aSAndroid Build Coastguard Worker// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12*6dbdd20aSAndroid Build Coastguard Worker// See the License for the specific language governing permissions and
13*6dbdd20aSAndroid Build Coastguard Worker// limitations under the License.
14*6dbdd20aSAndroid Build Coastguard Worker
15*6dbdd20aSAndroid Build Coastguard Workerexport function hash(s: string, max: number): number {
16*6dbdd20aSAndroid Build Coastguard Worker  let hash = 0x811c9dc5 & 0xfffffff;
17*6dbdd20aSAndroid Build Coastguard Worker  for (let i = 0; i < s.length; i++) {
18*6dbdd20aSAndroid Build Coastguard Worker    hash ^= s.charCodeAt(i);
19*6dbdd20aSAndroid Build Coastguard Worker    hash = (hash * 16777619) & 0xffffffff;
20*6dbdd20aSAndroid Build Coastguard Worker  }
21*6dbdd20aSAndroid Build Coastguard Worker  return Math.abs(hash) % max;
22*6dbdd20aSAndroid Build Coastguard Worker}
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