simulator: Make hypervisors generic for the resource type

This change moves the hypervisor implementations to the
opendc-simulator-resources module and makes them generic to the resource
type that is being used (e.g., CPU, disk or networking).

2 files changed, 24 insertions, 16 deletions

diff --git a/simulator/opendc-utils/src/main/kotlin/org/opendc/utils/TimerScheduler.kt b/simulator/opendc-utils/src/main/kotlin/org/opendc/utils/TimerScheduler.kt
index 9f40f26a..49964938 100644
--- a/simulator/opendc-utils/src/main/kotlin/org/opendc/utils/TimerScheduler.kt
+++ b/simulator/opendc-utils/src/main/kotlin/org/opendc/utils/TimerScheduler.kt
@@ -22,24 +22,28 @@
 
 package org.opendc.utils
 
-import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.*
 import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.channels.sendBlocking
-import kotlinx.coroutines.launch
 import kotlinx.coroutines.selects.select
 import java.time.Clock
 import java.util.*
+import kotlin.coroutines.CoroutineContext
 import kotlin.math.max
 
 /**
  * A TimerScheduler facilitates scheduled execution of future tasks.
  *
- * @property coroutineScope The [CoroutineScope] to run the tasks in.
+ * @property context The [CoroutineContext] to run the tasks with.
  * @property clock The clock to keep track of the time.
  */
 @OptIn(ExperimentalCoroutinesApi::class)
-public class TimerScheduler<T>(private val coroutineScope: CoroutineScope, private val clock: Clock) : AutoCloseable {
+public class TimerScheduler<T>(context: CoroutineContext, private val clock: Clock) : AutoCloseable {
+    /**
+     * The scope in which the scheduler runs.
+     */
+    private val scope = CoroutineScope(context + Job())
+
     /**
      * A priority queue containing the tasks to be scheduled in the future.
      */
@@ -58,7 +62,7 @@ public class TimerScheduler<T>(private val coroutineScope: CoroutineScope, priva
     /**
      * The scheduling job.
      */
-    private val job = coroutineScope.launch {
+    private val job = scope.launch {
         val timers = timers
         val queue = queue
         val clock = clock
@@ -71,7 +75,7 @@ public class TimerScheduler<T>(private val coroutineScope: CoroutineScope, priva
                 val delay = next?.let { max(0L, it - clock.millis()) } ?: return@select
 
                 onTimeout(delay) {
-                    while (queue.isNotEmpty()) {
+                    while (queue.isNotEmpty() && isActive) {
                         val timer = queue.peek()
                         val timestamp = clock.millis()
 
@@ -86,7 +90,11 @@ public class TimerScheduler<T>(private val coroutineScope: CoroutineScope, priva
 
                         if (!timer.isCancelled) {
                             timers.remove(timer.key)
-                            timer()
+                            try {
+                                timer()
+                            } catch (e: Throwable) {
+                                Thread.getDefaultUncaughtExceptionHandler().uncaughtException(Thread.currentThread(), e)
+                            }
                         }
                     }
 
@@ -101,7 +109,7 @@ public class TimerScheduler<T>(private val coroutineScope: CoroutineScope, priva
      */
     override fun close() {
         cancelAll()
-        job.cancel()
+        scope.cancel()
     }
 
     /**
diff --git a/simulator/opendc-utils/src/test/kotlin/org/opendc/utils/TimerSchedulerTest.kt b/simulator/opendc-utils/src/test/kotlin/org/opendc/utils/TimerSchedulerTest.kt
index 3a4acc90..1fcb5d38 100644
--- a/simulator/opendc-utils/src/test/kotlin/org/opendc/utils/TimerSchedulerTest.kt
+++ b/simulator/opendc-utils/src/test/kotlin/org/opendc/utils/TimerSchedulerTest.kt
@@ -38,7 +38,7 @@ internal class TimerSchedulerTest {
     fun testBasicTimer() {
         runBlockingTest {
             val clock = DelayControllerClockAdapter(this)
-            val scheduler = TimerScheduler<Int>(this, clock)
+            val scheduler = TimerScheduler<Int>(coroutineContext, clock)
 
             scheduler.startSingleTimer(0, 1000) {
                 scheduler.close()
@@ -51,7 +51,7 @@ internal class TimerSchedulerTest {
     fun testCancelNonExisting() {
         runBlockingTest {
             val clock = DelayControllerClockAdapter(this)
-            val scheduler = TimerScheduler<Int>(this, clock)
+            val scheduler = TimerScheduler<Int>(coroutineContext, clock)
 
             scheduler.cancel(1)
             scheduler.close()
@@ -62,7 +62,7 @@ internal class TimerSchedulerTest {
     fun testCancelExisting() {
         runBlockingTest {
             val clock = DelayControllerClockAdapter(this)
-            val scheduler = TimerScheduler<Int>(this, clock)
+            val scheduler = TimerScheduler<Int>(coroutineContext, clock)
 
             scheduler.startSingleTimer(0, 1000) {
                 assertFalse(false)
@@ -81,7 +81,7 @@ internal class TimerSchedulerTest {
     fun testCancelAll() {
         runBlockingTest {
             val clock = DelayControllerClockAdapter(this)
-            val scheduler = TimerScheduler<Int>(this, clock)
+            val scheduler = TimerScheduler<Int>(coroutineContext, clock)
 
             scheduler.startSingleTimer(0, 1000) {
                 assertFalse(false)
@@ -99,7 +99,7 @@ internal class TimerSchedulerTest {
     fun testOverride() {
         runBlockingTest {
             val clock = DelayControllerClockAdapter(this)
-            val scheduler = TimerScheduler<Int>(this, clock)
+            val scheduler = TimerScheduler<Int>(coroutineContext, clock)
 
             scheduler.startSingleTimer(0, 1000) {
                 assertFalse(false)
@@ -117,7 +117,7 @@ internal class TimerSchedulerTest {
     fun testStopped() {
         runBlockingTest {
             val clock = DelayControllerClockAdapter(this)
-            val scheduler = TimerScheduler<Int>(this, clock)
+            val scheduler = TimerScheduler<Int>(coroutineContext, clock)
 
             scheduler.close()
 
@@ -133,7 +133,7 @@ internal class TimerSchedulerTest {
     fun testNegativeDelay() {
         runBlockingTest {
             val clock = DelayControllerClockAdapter(this)
-            val scheduler = TimerScheduler<Int>(this, clock)
+            val scheduler = TimerScheduler<Int>(coroutineContext, clock)
 
             assertThrows<IllegalArgumentException> {
                 scheduler.startSingleTimer(1, -1) {