Native Library loading rework

ffi/build.gradle

@@ -19,15 +19,25 @@ compileJava {
 
 task buildFfiBridge(type: Exec) {
     workingDir projectDir
-    if (file("./ffi_build.sh").isFile()) { 
-      commandLine 'sh', '-c', './ffi_build.sh'
+    if (file("./ffi_build.sh").isFile()) {
+        commandLine 'sh', '-c', './ffi_build.sh'
     }
     else {
+        // Enter the swig directory and make the 'build' target
         commandLine 'make', '-C', 'swig', 'build'
     }
 }
 compileJava.dependsOn buildFfiBridge
 
+task cleanFfiBridge(type: Exec) {
+    workingDir projectDir
+    if (!file("./ffi_build.sh").isFile()) {
+        // Enter the swig directory and make the 'clean' target
+        commandLine 'make', '-C', 'swig', 'clean'
+    }
+}
+clean.dependsOn cleanFfiBridge
+
 jar {
     archiveClassifier = ''
     archiveAppendix = 'ffi'

ffi/src/main/java/com/antithesis/ffi/internal/CoverageHandler.java

@@ -0,0 +1,8 @@
+package com.antithesis.ffi.internal;
+
+public interface CoverageHandler {
+
+    public long initializeModuleCoverage(long edgeCount, String symbolFilePath);
+
+    public void notifyModuleEdge(long edgePlusModule);
+}

ffi/src/main/java/com/antithesis/ffi/internal/FfiHandler.java

@@ -1,20 +1,16 @@
 package com.antithesis.ffi.internal;
 
-import java.nio.charset.StandardCharsets;
 import java.util.Optional;
-import java.util.logging.Logger;
 
-public class FfiHandler implements OutputHandler {
+public class FfiHandler implements OutputHandler, CoverageHandler {
 
     private static long offset = -1;
 
     public static Optional<OutputHandler> get() {
-        try {
-            FfiWrapperJNI.loadLibrary();
+        if(FfiWrapperJNI.LOAD_LIBRARY_MARKER) {
             return Optional.of(new FfiHandler());
-        } catch (Throwable e) {
-            return Optional.empty();
         }
+        return Optional.empty();
     }
 
     @Override
@@ -39,15 +35,12 @@ public long initializeModuleCoverage(long edgeCount, String symbolFilePath) {
         }
         offset = FfiWrapperJNI.init_coverage_module(edgeCount, symbolFilePath);
         String msg = String.format("Initialized Java module at offset 0x%016x with %d edges; symbol file %s", offset, edgeCount, symbolFilePath);
-        // TODO: (@shomik) logger.info(msg); 
+        System.out.println(msg);
         return offset;
     }
 
     @Override
     public void notifyModuleEdge(long edgePlusModule) {
-        // Right now, the Java implementation defers completely to the native library. 
-        // See instrumentation.h to understand the logic here. The shim (i.e. StaticModule.java)
-        // is responsible for handling the return value.
         FfiWrapperJNI.notify_coverage(edgePlusModule);
     }
 

ffi/src/main/java/com/antithesis/ffi/internal/OutputHandler.java

@@ -4,9 +4,5 @@ public interface OutputHandler {
     void output(String value);
 
     long random();
-
-    long initializeModuleCoverage(long edgeCount, String symbolFilePath);
-
-    void notifyModuleEdge(long edgePlusModule);
 }
 

ffi/swig/FfiWrapper.i

@@ -30,17 +30,19 @@ import java.nio.file.StandardCopyOption;
 %}
 
 %pragma(java) jniclasscode=%{
-
-
     private static final String NATIVE_LIBRARY_PATH = "/usr/lib/libvoidstar.so";
 
     public static boolean hasNativeLibrary() {
        return Files.exists(Paths.get(NATIVE_LIBRARY_PATH));
     }
 
-    public static void loadLibrary() throws IOException {
-        try {
-            if (hasNativeLibrary()) {
+    // Static variables initialization is guaranteed to execute by the Java Language Spec
+    public static boolean LOAD_LIBRARY_MARKER = loadLibrary();
+
+    private static boolean loadLibrary() {
+        boolean nativeLibraryFound = hasNativeLibrary();
+        if (nativeLibraryFound) {
+            try {
                 System.load(NATIVE_LIBRARY_PATH);
                 File file = File.createTempFile("libFfiWrapper", ".so");
                 try (InputStream link = (Thread.currentThread().getContextClassLoader().getResourceAsStream("libFfiWrapper.so"))){
@@ -50,13 +52,18 @@ import java.nio.file.StandardCopyOption;
                         StandardCopyOption.REPLACE_EXISTING);
                     System.load(file.getAbsoluteFile().toString());
                 }
-            } else {
-                throw new RuntimeException("Native code library failed to load");
+            } catch (UnsatisfiedLinkError e) {
+                System.err.println("Failed to load a native library:" + e);
+                return false;
+            } catch (IOException e) {
+                System.err.println("Failed to load FFI wrapper from resources:" + e);
+                return false;
+            } catch (Exception e) {
+                System.err.println("Unexpected error: " + e);
+                return false;
             }
-        } catch (UnsatisfiedLinkError e) {
-            System.err.println("Native code library failed to load. \n" + e);
-            throw e;
         }
+        return nativeLibraryFound;
     }
 %}
 

ffi/swig/Makefile

@@ -1,4 +1,4 @@
-build: 
+build:
 	# Generate java and .c files needed for JNI
 	swig -java -package com.antithesis.ffi.internal FfiWrapper.i
 
@@ -12,7 +12,7 @@ build:
 	# ldd will fail to resolve this outside of the Antithesis runtime environment
 	# libFfiWrapper is only loaded if libvoidstar is successfully
 	# loaded first.
-	patchelf --add-needed libvoidstar.so ./libFfiWrapper.so
+	patchelf --add-needed /usr/lib/libvoidstar.so ./libFfiWrapper.so
 
 	# Move the wrapper into a folder so it can be added into the target jar
 	mkdir -p ../src/main/resources

sdk/build.gradle

@@ -12,7 +12,7 @@ dependencies {
     if (file("libs/antithesis-ffi-${project.version}.jar").isFile()) {
         implementation(files("libs/antithesis-ffi-${project.version}.jar"))
     } else {
-     implementation(project(":ffi"))
+        implementation(project(":ffi"))
     }
 
     // Use JUnit Jupiter for testing.

sdk/src/main/java/com/antithesis/sdk/internal/HandlerFactory.java

@@ -62,14 +62,6 @@ public long random() {
             return new Random().nextLong();
         }
 
-        @Override
-        public long initializeModuleCoverage(long edgeCount, String symbolFilePath) {
-            return edgeCount;
-        }
-
-        @Override
-        public void notifyModuleEdge(long edgePlusModule) {
-        }
     }
 
     private static class LocalHandler implements OutputHandler {
@@ -102,7 +94,6 @@ public void output(final String value) {
                 writer.write("\n");
                 writer.flush();
             } catch (IOException ignored) {
-                // TODO (@shomik) logging
             }
         }
 
@@ -111,14 +102,6 @@ public long random() {
             return new Random().nextLong();
         }
 
-        @Override
-        public long initializeModuleCoverage(long edgeCount, String symbolFilePath) {
-            return 0;
-        }
-
-        @Override
-        public void notifyModuleEdge(long edgePlusModule) {
-        }
     }
 
 }

sdk/src/main/java/com/antithesis/sdk/internal/Internal.java

@@ -21,11 +21,4 @@ public static void dispatchOutput(final ObjectNode s) {
         }
     }
 
-    public static long dispatchInitializeModuleCoverage(long edgeCount, String symbolFilePath) {
-        return HandlerFactory.get().initializeModuleCoverage(edgeCount, symbolFilePath);
-    }
-
-    public static void dispatchNotifyModuleEdge(long edgePlusModule) {
-        HandlerFactory.get().notifyModuleEdge(edgePlusModule);
-    }
 }

sdk/src/test/java/com/antithesis/sdk/internal/InstrumentationTest.java

@@ -1,39 +1,29 @@
 package com.antithesis.sdk.internal;
 
-import org.junit.jupiter.api.Test;
-import static org.junit.jupiter.api.Assertions.fail;
-import static org.junit.jupiter.api.Assumptions.assumeTrue;
+import com.antithesis.ffi.internal.FfiWrapperJNI;
+import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ObjectNode;
-import com.fasterxml.jackson.core.JsonProcessingException;
+import org.junit.jupiter.api.Test;
 
-import com.antithesis.ffi.internal.FfiWrapperJNI;
+import static org.junit.jupiter.api.Assertions.fail;
+import static org.junit.jupiter.api.Assumptions.assumeTrue;
 
 public class InstrumentationTest {
     @Test
     void testRandom() {
-        assumeTrue(FfiWrapperJNI.hasNativeLibrary());
-        try {
-             FfiWrapperJNI.loadLibrary();
-        } catch (Throwable e) {
-            fail("Unable to load native library");
-        }
+        assumeTrue(FfiWrapperJNI.LOAD_LIBRARY_MARKER);
         FfiWrapperJNI.fuzz_get_random();
     }
 
     @Test
     void testJsonData() {
-        assumeTrue(FfiWrapperJNI.hasNativeLibrary());
+        assumeTrue(FfiWrapperJNI.LOAD_LIBRARY_MARKER);
 
         ObjectMapper mapper = new ObjectMapper();
         ObjectNode jsonNode = mapper.createObjectNode();
         jsonNode.put("hello", "world");
 
-        try {
-             FfiWrapperJNI.loadLibrary();
-        } catch (Throwable e) {
-            fail("Unable to load native library");
-        } 
         String theString = "";
         try {
             theString = mapper.writeValueAsString(jsonNode);
@@ -45,12 +35,7 @@ void testJsonData() {
 
     @Test
     void testFlush() {
-        assumeTrue(FfiWrapperJNI.hasNativeLibrary());
-        try {
-             FfiWrapperJNI.loadLibrary();
-        } catch (Throwable e) {
-            fail("Unable to load native library");
-        } 
+        assumeTrue(FfiWrapperJNI.LOAD_LIBRARY_MARKER);
         FfiWrapperJNI.fuzz_flush();
     }
 }