Make engine more resilient against init crashes

base/src/main/kotlin/de/staropensource/engine/base/Engine.kt

@@ -20,6 +20,7 @@
 
 package de.staropensource.engine.base
 
+import de.staropensource.engine.base.exception.EngineInitializationFailureException
 import de.staropensource.engine.base.utility.Environment
 import de.staropensource.engine.base.utility.FileAccess
 import de.staropensource.engine.logging.Logger
@@ -78,31 +79,38 @@ class Engine private constructor() {
          * and generally performs actions which
          * should only be executed once.
          *
+         * @return `true` if bootstrapping was performed successfully, `false` if failed
          * @throws Throwable on initialization error
          * @since v1-alpha10
          */
         @JvmStatic
         @Throws(Throwable::class)
-        private fun bootstrap() {
+        private fun bootstrap(): Boolean {
             if (state != State.UNINITIALIZED || bootstrapping != null)
-                return
+                return true
 
+            try {
                 bootstrapping = true
                 logger.info("Bootstrapping")
 
                 // Run bootstrapping code
 
                 bootstrapping = false
+                return true
+            } catch (exception: Exception) {
+                logger.crash("Engine failed to bootstrap", throwable = exception, fatal = true)
+                return false
+            }
         }
 
         /**
          * Initializes the engine.
          *
-         * @throws Throwable on initialization error
+         * @throws EngineInitializationFailureException on initialization error
          * @since v1-alpha10
          */
         @JvmStatic
-        @Throws(Throwable::class)
+        @Throws(EngineInitializationFailureException::class)
         fun initialize() {
             // Abort if initializing, shutting down
             // or the engine has crashed
@@ -114,8 +122,10 @@ class Engine private constructor() {
             ) return
 
             // Bootstrap if not already done so
-            bootstrap()
+            if (!bootstrap())
+                return
 
+            try {
                 state = State.INITIALIZING
                 logger.info("Initializing")
 
@@ -124,6 +134,10 @@ class Engine private constructor() {
                 FileAccess.updateDefaultPaths()
 
                 state = State.INITIALIZED
+            } catch (exception: Exception) {
+                logger.crash("Engine failed to initialize", throwable = exception, fatal = true)
+                throw EngineInitializationFailureException(exception)
+            }
         }
 
         /**

base/src/main/kotlin/de/staropensource/engine/base/exception/EngineInitializationFailureException.kt

@@ -0,0 +1,32 @@
+/*
+ * STAROPENSOURCE ENGINE SOURCE FILE
+ * Copyright (c) 2024 The StarOpenSource Engine Authors
+ * Licensed under the GNU Affero General Public License v3
+ * with an exception allowing classpath linking.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.engine.base.exception
+
+/**
+ * Thrown when the engine fails to
+ * initialize or bootstrap itself.
+ *
+ * After this occurs, it will no longer
+ * be possible to initialize the engine.
+ *
+ * @since v1-alpha10
+ */
+class EngineInitializationFailureException(val throwable: Throwable) : RuntimeException("The StarOpenSource Engine failed to initialize", throwable)