[GR-36191] Add option to explicitly make jvm shim DLL.

PullRequest: graal/13651

Author: pejovica

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/jdk/JNIRegistrationSupport.java

@@ -52,18 +52,20 @@
 import org.graalvm.compiler.nodes.graphbuilderconf.GraphBuilderContext;
 import org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugin.RequiredInvocationPlugin;
 import org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugins.Registration;
+import org.graalvm.compiler.options.Option;
 import org.graalvm.compiler.phases.util.Providers;
 import org.graalvm.nativeimage.ImageSingletons;
 import org.graalvm.nativeimage.Platforms;
 import org.graalvm.nativeimage.impl.InternalPlatform;
 
 import com.oracle.svm.core.BuildArtifacts;
 import com.oracle.svm.core.ParsingReason;
+import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
 import com.oracle.svm.core.feature.InternalFeature;
 import com.oracle.svm.core.jdk.JNIRegistrationUtil;
 import com.oracle.svm.core.jdk.NativeLibrarySupport;
 import com.oracle.svm.core.meta.SubstrateObjectConstant;
-import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
+import com.oracle.svm.core.option.HostedOptionKey;
 import com.oracle.svm.core.util.InterruptImageBuilding;
 import com.oracle.svm.core.util.VMError;
 import com.oracle.svm.hosted.FeatureImpl.AfterImageWriteAccessImpl;
@@ -80,6 +82,11 @@
 @AutomaticallyRegisteredFeature
 public final class JNIRegistrationSupport extends JNIRegistrationUtil implements InternalFeature {
 
+    public static class Options {
+        @Option(help = "Create a `jvm` shim for native libraries that link against that library.")//
+        public static final HostedOptionKey<Boolean> CreateJvmShim = new HostedOptionKey<>(false);
+    }
+
     private final ConcurrentMap<String, Boolean> registeredLibraries = new ConcurrentHashMap<>();
     private NativeLibraries nativeLibraries = null;
     private boolean isSunMSCAPIProviderReachable = false;
@@ -159,6 +166,11 @@ private void addShimExports(String shimName, String... exports) {
 
     @Override
     public void beforeImageWrite(BeforeImageWriteAccess access) {
+        if (shimExports.containsKey("jvm") || Options.CreateJvmShim.getValue()) {
+            /* When making a `jvm` shim, also re-export the JNI functions that VM exports. */
+            addJvmShimExports("JNI_CreateJavaVM", "JNI_GetCreatedJavaVMs", "JNI_GetDefaultJavaVMInitArgs");
+        }
+
         if (isWindows()) {
             ((BeforeImageWriteAccessImpl) access).registerLinkerInvocationTransformer(linkerInvocation -> {
                 /* Make sure the native image exports all the symbols necessary for shim DLLs. */