• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1/*
2 * Copyright (c) 2022-2025 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16import { int32 } from "@koalaui/common"
17
18export type ResourceId = int32
19
20interface ResourceInfo {
21    resource: object
22    holdersCount: int32
23}
24
25export class ResourceHolder {
26    private static nextResourceId: ResourceId = 100
27    private resources: Map<ResourceId, ResourceInfo> = new Map<ResourceId, ResourceInfo>()
28    private static _instance: ResourceHolder|undefined = undefined
29    static instance(): ResourceHolder {
30        if (ResourceHolder._instance == undefined) {
31            ResourceHolder._instance = new ResourceHolder()
32        }
33        return ResourceHolder._instance!
34    }
35
36    public hold(resourceId: ResourceId) {
37        if (!this.resources.has(resourceId))
38            throw new Error(`Resource ${resourceId} does not exists, can not hold`)
39        this.resources.get(resourceId)!.holdersCount++
40    }
41
42    public release(resourceId: ResourceId) {
43        if (!this.resources.has(resourceId))
44            throw new Error(`Resource ${resourceId} does not exists, can not release`)
45        const resource = this.resources.get(resourceId)!
46        resource.holdersCount--
47        if (resource.holdersCount <= 0)
48            this.resources.delete(resourceId)
49    }
50
51    public registerAndHold(resource: object): ResourceId {
52        const resourceId = ResourceHolder.nextResourceId++
53        this.resources.set(resourceId, {
54            resource: resource,
55            holdersCount: 1,
56        })
57        return resourceId
58    }
59
60    public get(resourceId: ResourceId): object {
61        if (!this.resources.has(resourceId))
62            throw new Error(`Resource ${resourceId} does not exists`)
63        return this.resources.get(resourceId)!.resource
64    }
65
66    public has(resourceId: ResourceId): boolean {
67        return this.resources.has(resourceId)
68    }
69}
70