Trace.kt
/*
* Copyright 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.compose.runtime
internal expect object Trace {
/**
* Writes a trace message to indicate that a given section of code has begun.
* This call must be followed by a corresponding call to [endSection] on the same thread.
*
* @return An arbitrary token which will be supplied to the corresponding call
* to [endSection]. May be null.
*/
fun beginSection(name: String): Any?
/**
* Writes a trace message to indicate that a given section of code has ended.
* This call must be preceded by a corresponding call to [beginSection].
* Calling this method will mark the end of the most recently begun section of code, so care
* must be taken to ensure that `beginSection` / `endSection` pairs are properly nested and
* called from the same thread.
*
* @param token The instance returned from the corresponding call to [beginSection].
*/
fun endSection(token: Any?)
}
/**
* Wrap the specified [block] in calls to [Trace.beginSection] (with the supplied [sectionName])
* and [Trace.endSection].
*/
internal inline fun <T> trace(sectionName: String, block: () -> T): T {
val token = Trace.beginSection(sectionName)
try {
return block()
} finally {
Trace.endSection(token)
}
}