ART: Add GetClassSignature

Add support to retrieve the signature of a JNI class.

Add a test.

Bug: 31684578
Test: m test-art-host-run-test-912-classes
Change-Id: I1cf946996f9089cb5d41e93b4f1064193e9d6350
diff --git a/test/912-classes/build b/test/912-classes/build
new file mode 100755
index 0000000..898e2e5
--- /dev/null
+++ b/test/912-classes/build
@@ -0,0 +1,17 @@
+#!/bin/bash
+#
+# Copyright 2016 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+./default-build "$@" --experimental agents
diff --git a/test/912-classes/classes.cc b/test/912-classes/classes.cc
new file mode 100644
index 0000000..4bf329c
--- /dev/null
+++ b/test/912-classes/classes.cc
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "classes.h"
+
+#include <stdio.h>
+
+#include "base/macros.h"
+#include "jni.h"
+#include "openjdkjvmti/jvmti.h"
+#include "ScopedLocalRef.h"
+
+#include "ti-agent/common_load.h"
+
+namespace art {
+namespace Test912Classes {
+
+extern "C" JNIEXPORT jobjectArray JNICALL Java_Main_getClassSignature(
+    JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED, jclass klass) {
+  char* sig;
+  char* gen;
+  jvmtiError result = jvmti_env->GetClassSignature(klass, &sig, &gen);
+  if (result != JVMTI_ERROR_NONE) {
+    char* err;
+    jvmti_env->GetErrorName(result, &err);
+    printf("Failure running GetClassSignature: %s\n", err);
+    return nullptr;
+  }
+
+  ScopedLocalRef<jclass> obj_class(env, env->FindClass("java/lang/String"));
+  if (obj_class.get() == nullptr) {
+    return nullptr;
+  }
+
+  jobjectArray ret = env->NewObjectArray(2, obj_class.get(), nullptr);
+  if (ret == nullptr) {
+    return ret;
+  }
+
+  ScopedLocalRef<jstring> sig_str(env, sig == nullptr ? nullptr : env->NewStringUTF(sig));
+  ScopedLocalRef<jstring> gen_str(env, gen == nullptr ? nullptr : env->NewStringUTF(gen));
+
+  env->SetObjectArrayElement(ret, 0, sig_str.get());
+  env->SetObjectArrayElement(ret, 1, gen_str.get());
+
+  // Need to deallocate the strings.
+  if (sig != nullptr) {
+    jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(sig));
+  }
+  if (gen != nullptr) {
+    jvmti_env->Deallocate(reinterpret_cast<unsigned char*>(gen));
+  }
+
+  return ret;
+}
+
+// Don't do anything
+jint OnLoad(JavaVM* vm,
+            char* options ATTRIBUTE_UNUSED,
+            void* reserved ATTRIBUTE_UNUSED) {
+  if (vm->GetEnv(reinterpret_cast<void**>(&jvmti_env), JVMTI_VERSION_1_0)) {
+    printf("Unable to get jvmti env!\n");
+    return 1;
+  }
+  return 0;
+}
+
+}  // namespace Test912Classes
+}  // namespace art
diff --git a/test/912-classes/classes.h b/test/912-classes/classes.h
new file mode 100644
index 0000000..62fb203
--- /dev/null
+++ b/test/912-classes/classes.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_TEST_912_CLASSES_CLASSES_H_
+#define ART_TEST_912_CLASSES_CLASSES_H_
+
+#include <jni.h>
+
+namespace art {
+namespace Test912Classes {
+
+jint OnLoad(JavaVM* vm, char* options, void* reserved);
+
+}  // namespace Test912Classes
+}  // namespace art
+
+#endif  // ART_TEST_912_CLASSES_CLASSES_H_
diff --git a/test/912-classes/expected.txt b/test/912-classes/expected.txt
new file mode 100644
index 0000000..71b22f4
--- /dev/null
+++ b/test/912-classes/expected.txt
@@ -0,0 +1,7 @@
+[Ljava/lang/Object;, null]
+[Ljava/lang/String;, null]
+[Ljava/lang/Math;, null]
+[Ljava/util/List;, null]
+[L$Proxy0;, null]
+[I, null]
+[[D, null]
diff --git a/test/912-classes/info.txt b/test/912-classes/info.txt
new file mode 100644
index 0000000..875a5f6
--- /dev/null
+++ b/test/912-classes/info.txt
@@ -0,0 +1 @@
+Tests basic functions in the jvmti plugin.
diff --git a/test/912-classes/run b/test/912-classes/run
new file mode 100755
index 0000000..64bbb98
--- /dev/null
+++ b/test/912-classes/run
@@ -0,0 +1,43 @@
+#!/bin/bash
+#
+# Copyright 2016 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+plugin=libopenjdkjvmtid.so
+agent=libtiagentd.so
+lib=tiagentd
+if  [[ "$@" == *"-O"* ]]; then
+  agent=libtiagent.so
+  plugin=libopenjdkjvmti.so
+  lib=tiagent
+fi
+
+if [[ "$@" == *"--jvm"* ]]; then
+  arg="jvm"
+else
+  arg="art"
+fi
+
+if [[ "$@" != *"--debuggable"* ]]; then
+  other_args=" -Xcompiler-option --debuggable "
+else
+  other_args=""
+fi
+
+./default-run "$@" --experimental agents \
+                   --experimental runtime-plugins \
+                   --runtime-option -agentpath:${agent}=912-classes,${arg} \
+                   --android-runtime-option -Xplugin:${plugin} \
+                   ${other_args} \
+                   --args ${lib}
diff --git a/test/912-classes/src/Main.java b/test/912-classes/src/Main.java
new file mode 100644
index 0000000..025584e
--- /dev/null
+++ b/test/912-classes/src/Main.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.lang.reflect.Proxy;
+import java.util.Arrays;
+
+public class Main {
+  public static void main(String[] args) throws Exception {
+    System.loadLibrary(args[1]);
+
+    doTest();
+  }
+
+  public static void doTest() throws Exception {
+    testClass("java.lang.Object");
+    testClass("java.lang.String");
+    testClass("java.lang.Math");
+    testClass("java.util.List");
+
+    testClass(getProxyClass());
+
+    testClass(int.class);
+    testClass(double[].class);
+  }
+
+  private static Class<?> proxyClass = null;
+
+  private static Class<?> getProxyClass() throws Exception {
+    if (proxyClass != null) {
+      return proxyClass;
+    }
+
+    proxyClass = Proxy.getProxyClass(Main.class.getClassLoader(), new Class[] { Runnable.class });
+    return proxyClass;
+  }
+
+  private static void testClass(String className) throws Exception {
+    Class<?> base = Class.forName(className);
+    testClass(base);
+  }
+
+  private static void testClass(Class<?> base) throws Exception {
+    String[] result = getClassSignature(base);
+    System.out.println(Arrays.toString(result));
+  }
+
+  private static native String[] getClassSignature(Class<?> c);
+}
diff --git a/test/Android.bp b/test/Android.bp
index 37e1fc0..af70486 100644
--- a/test/Android.bp
+++ b/test/Android.bp
@@ -255,6 +255,7 @@
         "909-attach-agent/attach.cc",
         "910-methods/methods.cc",
         "911-get-stack-trace/stack_trace.cc",
+        "912-classes/classes.cc",
     ],
     shared_libs: [
         "libbase",
diff --git a/test/ti-agent/common_load.cc b/test/ti-agent/common_load.cc
index 7faf700..4db953c 100644
--- a/test/ti-agent/common_load.cc
+++ b/test/ti-agent/common_load.cc
@@ -35,6 +35,7 @@
 #include "909-attach-agent/attach.h"
 #include "910-methods/methods.h"
 #include "911-get-stack-trace/stack_trace.h"
+#include "912-classes/classes.h"
 
 namespace art {
 
@@ -62,6 +63,7 @@
   { "909-attach-agent", nullptr, Test909AttachAgent::OnAttach },
   { "910-methods", Test910Methods::OnLoad, nullptr },
   { "911-get-stack-trace", Test911GetStackTrace::OnLoad, nullptr },
+  { "912-classes", Test912Classes::OnLoad, nullptr },
 };
 
 static AgentLib* FindAgent(char* name) {