Critical section for coroutines

critical_section_for_coroutines.kt

import java.util.concurrent.ConcurrentHashMap
import kotlin.coroutines.Continuation
import kotlin.coroutines.resume
import kotlin.coroutines.suspendCoroutine

class KCriticalSection {
    private val suspendedJobs = ConcurrentHashMap<Int, Continuation<Boolean>>()
    private var id = AtomicInteger(1000)
    @Volatile private var isInsideCriticalSection = false

    suspend fun <T> synchronized(block: suspend () -> T): T {
        val thisJobId = id.getAndIncrement()
        while (isInsideCriticalSection) {
            suspendCoroutine { cont -> // <-- suspending call
                suspendedJobs[thisJobId] = cont
            }
            suspendedJobs.remove(thisJobId)
        }
        isInsideCriticalSection = true

        val result = block() // <-- suspending call

        isInsideCriticalSection = false
        suspendedJobs.forEach { (id, cont) ->
            cont.resume(true)
        }

        return result
    }
}