Trace JNI accesses

Author: DSouzaM

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jni/access/JNIAccessibleMethodDescriptor.java

@@ -98,10 +98,19 @@ public boolean isClassInitializer() {
         return WRAPPED_CSTRING_EQUIVALENCE.equals(name, INITIALIZER_NAME);
     }
 
+    /**
+     * Returns the method name as a String. Can be used if the descriptor is known to be a String
+     * (i.e., it does not come from a JNI call); otherwise, use {@link #getNameConvertToString()}.
+     */
     public String getName() {
         return (String) name;
     }
 
+    /**
+     * Returns the method signature as a String. Can be used if the descriptor is known to be a
+     * String (i.e., it does not come from a JNI call); otherwise, use
+     * {@link #getSignatureConvertToString()}.
+     */
     public String getSignature() {
         return (String) signature;
     }
@@ -113,6 +122,13 @@ public String getNameConvertToString() {
         return name.toString();
     }
 
+    /**
+     * Performs a potentially costly conversion to string, only for slow paths.
+     */
+    public String getSignatureConvertToString() {
+        return signature.toString();
+    }
+
     public String getSignatureWithoutReturnType() {
         String signatureString = signature.toString();
         int parametersEnd = signatureString.lastIndexOf(')');

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jni/access/JNIReflectionDictionary.java

@@ -41,6 +41,8 @@
 import org.graalvm.nativeimage.Platforms;
 import org.graalvm.word.Pointer;
 
+import com.oracle.svm.configure.config.ConfigurationMemberInfo;
+import com.oracle.svm.configure.config.ConfigurationType;
 import com.oracle.svm.core.SubstrateOptions;
 import com.oracle.svm.core.Uninterruptible;
 import com.oracle.svm.core.heap.Heap;
@@ -52,6 +54,7 @@
 import com.oracle.svm.core.layeredimagesingleton.MultiLayeredImageSingleton;
 import com.oracle.svm.core.layeredimagesingleton.UnsavedSingleton;
 import com.oracle.svm.core.log.Log;
+import com.oracle.svm.core.metadata.MetadataTracer;
 import com.oracle.svm.core.snippets.KnownIntrinsics;
 import com.oracle.svm.core.util.ImageHeapMap;
 import com.oracle.svm.core.util.Utf8.WrappedAsciiCString;
@@ -185,6 +188,9 @@ public Iterable<JNIAccessibleClass> getClasses() {
     public static Class<?> getClassObjectByName(CharSequence name) {
         for (var dictionary : layeredSingletons()) {
             JNIAccessibleClass clazz = dictionary.classesByName.get(name);
+            if (MetadataTracer.Options.MetadataTracingSupport.getValue() && clazz != null && MetadataTracer.singleton().enabled()) {
+                MetadataTracer.singleton().traceJNIType(convertFindClassNameToBinaryName(name.toString()));
+            }
             clazz = checkClass(clazz, name);
             if (clazz != null) {
                 return clazz.getClassObject();
@@ -194,6 +200,16 @@ public static Class<?> getClassObjectByName(CharSequence name) {
         return null;
     }
 
+    /**
+     * FindClass's argument is either an internal class name (e.g., {@code pkg/sub/Class}) or an
+     * array type signature (e.g., {@code [Lpkg/sub/Class;}). Converts the argument to a regular
+     * binary name (e.g., {@code pkg.sub.Class}.
+     */
+    private static String convertFindClassNameToBinaryName(String name) {
+        String internalName = (name.charAt(0) != '[') ? ('L' + name + ';') : name;
+        return MetaUtil.internalNameToJava(internalName, true, true);
+    }
+
     private static JNIAccessibleClass checkClass(JNIAccessibleClass clazz, CharSequence name) {
         if (throwMissingRegistrationErrors() && clazz == null) {
             MissingJNIRegistrationUtils.forClass(name.toString());
@@ -277,6 +293,10 @@ private static JNIAccessibleMethod getDeclaredMethod(Class<?> classObject, JNIAc
                 foundClass = true;
                 JNIAccessibleMethod method = clazz.getMethod(descriptor);
                 if (method != null) {
+                    if (MetadataTracer.Options.MetadataTracingSupport.getValue() && MetadataTracer.singleton().enabled()) {
+                        ConfigurationType clazzType = MetadataTracer.singleton().traceJNIType(classObject.getName());
+                        clazzType.addMethod(descriptor.getNameConvertToString(), descriptor.getSignatureConvertToString(), ConfigurationMemberInfo.ConfigurationMemberDeclaration.DECLARED);
+                    }
                     return method;
                 }
             }
@@ -332,6 +352,10 @@ private static JNIAccessibleField getDeclaredField(Class<?> classObject, CharSeq
                 foundClass = true;
                 JNIAccessibleField field = clazz.getField(name);
                 if (field != null && (field.isStatic() == isStatic || field.isNegative())) {
+                    if (MetadataTracer.Options.MetadataTracingSupport.getValue() && MetadataTracer.singleton().enabled()) {
+                        ConfigurationType clazzType = MetadataTracer.singleton().traceJNIType(classObject.getName());
+                        clazzType.addField(name.toString(), ConfigurationMemberInfo.ConfigurationMemberDeclaration.DECLARED, false);
+                    }
                     return field;
                 }
             }

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/metadata/MetadataTracer.java

@@ -36,6 +36,7 @@
 import org.graalvm.nativeimage.impl.UnresolvedConfigurationCondition;
 
 import com.oracle.svm.configure.config.ConfigurationSet;
+import com.oracle.svm.configure.config.ConfigurationType;
 import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
 import com.oracle.svm.core.feature.InternalFeature;
 import com.oracle.svm.core.jdk.RuntimeSupport;
@@ -79,6 +80,11 @@ public boolean enabled() {
         return config != null;
     }
 
+    public ConfigurationType traceJNIType(String className) {
+        assert enabled();
+        return config.getJniConfiguration().getOrCreateType(UnresolvedConfigurationCondition.alwaysTrue(), className);
+    }
+
     public void traceResource(String resourceName, String moduleName) {
         assert enabled();
         config.getResourceConfiguration().addGlobPattern(UnresolvedConfigurationCondition.alwaysTrue(), resourceName, moduleName);