[GR-68493] Web-image support for running espresso in web-image

Author: simongruenbacher

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/Target_java_lang_Thread.java

@@ -367,6 +367,7 @@ private static void yield0() {
         PlatformThreads.singleton().yieldCurrent();
     }
 
+    @Platforms(InternalPlatform.NATIVE_ONLY.class)
     @Substitute
     private static void sleepNanos0(long nanos) throws InterruptedException {
         // Virtual threads are handled in sleep()

web-image/src/com.oracle.svm.webimage/src/com/oracle/svm/webimage/substitute/system/WebImageJavaLangSubstitutions.java

@@ -59,6 +59,7 @@
 import com.oracle.svm.webimage.platform.WebImageJSPlatform;
 import com.oracle.svm.webimage.platform.WebImagePlatform;
 import com.oracle.svm.webimage.platform.WebImageWasmGCPlatform;
+import org.graalvm.nativeimage.ProcessProperties;
 
 /*
  * Checkstyle: stop method name check
@@ -232,7 +233,11 @@ private static void yield() {
     }
 
     @Substitute
-    private static void sleep(long millis) throws InterruptedException {
+    private static void sleep(long millis) {
+    }
+
+    @Substitute
+    private static void sleepNanos0(long nanos) {
     }
 
     @Substitute
@@ -257,6 +262,16 @@ public static Map<Thread, StackTraceElement[]> getAllStackTraces() {
     }
 }
 
+@TargetClass(className = "java.lang.VirtualThread")
+@SuppressWarnings("unused")
+final class Target_java_lang_VirtualThread_Web {
+    @Substitute
+    @SuppressWarnings("static-method")
+    private void runContinuation() {
+        throw new UnsupportedOperationException("VirtualThread.runContinuation");
+    }
+}
+
 @TargetClass(java.lang.System.class)
 @SuppressWarnings("unused")
 final class Target_java_lang_System_Web {
@@ -879,6 +894,29 @@ public static Logger getLogger(String name) {
     }
 }
 
+@TargetClass(className = "java.lang.ProcessHandleImpl")
+@SuppressWarnings("unused")
+final class Target_java_lang_ProcessHandleImpl_Web {
+
+    @Substitute
+    private static void initNative() {
+        // Do nothing. Native code only gathers some information about the underlying system.
+    }
+
+    @Substitute
+    private static long getCurrentPid0() {
+        return ProcessProperties.getProcessID();
+    }
+
+    @Substitute
+    private static long isAlive0(long pid) {
+        if (pid == ProcessProperties.getProcessID()) {
+            return 0L;
+        }
+        return -1L;
+    }
+}
+
 class IsLinux implements BooleanSupplier {
     @Override
     public boolean getAsBoolean() {

web-image/src/com.oracle.svm.webimage/src/com/oracle/svm/webimage/substitute/system/WebImageSunMiscSubstitutions.java

@@ -107,7 +107,8 @@ private static int findSignal0(String sigName) {
     }
 
     @Substitute
-    public static synchronized Signal.Handler handle(Signal sig, Signal.Handler handler) throws IllegalArgumentException {
+    @SuppressWarnings("unused")
+    public static Signal.Handler handle(Signal sig, Signal.Handler handler) throws IllegalArgumentException {
         throw new IllegalArgumentException("cannot register signal handles in webimage.");
     }
 }