1 /*
2  * Copyright 2024 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 
17 package androidx.tracing.driver
18 
19 import kotlin.coroutines.AbstractCoroutineContextElement
20 import kotlin.coroutines.CoroutineContext
21 import kotlin.coroutines.coroutineContext
22 
23 /** An [AbstractCoroutineContextElement] that can hold to the [List] of current `flowId`s.. */
24 internal class FlowContextElement(internal val flowIds: List<Long>) :
25     AbstractCoroutineContextElement(KEY) {
26 
27     internal companion object {
28         internal val KEY: CoroutineContext.Key<FlowContextElement> =
29             object : CoroutineContext.Key<FlowContextElement> {}
30     }
31 }
32 
33 /** Useful in the context of structured concurrency to keep track of flows. */
obtainFlowContextnull34 internal suspend fun obtainFlowContext(): FlowContextElement? {
35     return coroutineContext[FlowContextElement.KEY]
36 }
37