ART: Add method name support to TI

Add support for GetMethodName.

Bug: 31684812
Test: m test-art-host
Change-Id: I55e7b6dac7e7193c3d9979ebb289b0e2849ad030
diff --git a/runtime/openjdkjvmti/Android.bp b/runtime/openjdkjvmti/Android.bp
index de6683c..c8675a4 100644
--- a/runtime/openjdkjvmti/Android.bp
+++ b/runtime/openjdkjvmti/Android.bp
@@ -21,6 +21,7 @@
            "heap.cc",
            "object_tagging.cc",
            "OpenjdkJvmTi.cc",
+           "ti_method.cc",
            "transform.cc"],
     include_dirs: ["art/runtime"],
     shared_libs: [
diff --git a/runtime/openjdkjvmti/OpenjdkJvmTi.cc b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
index b91acb6..ed99009 100644
--- a/runtime/openjdkjvmti/OpenjdkJvmTi.cc
+++ b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
@@ -47,6 +47,7 @@
 #include "scoped_thread_state_change-inl.h"
 #include "thread_list.h"
 #include "thread-inl.h"
+#include "ti_method.h"
 #include "transform.h"
 
 // TODO Remove this at some point by annotating all the methods. It was put in to make the skeleton
@@ -635,7 +636,7 @@
                                   char** name_ptr,
                                   char** signature_ptr,
                                   char** generic_ptr) {
-    return ERR(NOT_IMPLEMENTED);
+    return MethodUtil::GetMethodName(env, method, name_ptr, signature_ptr, generic_ptr);
   }
 
   static jvmtiError GetMethodDeclaringClass(jvmtiEnv* env,
diff --git a/runtime/openjdkjvmti/art_jvmti.h b/runtime/openjdkjvmti/art_jvmti.h
index 66d0937..78cb9a0 100644
--- a/runtime/openjdkjvmti/art_jvmti.h
+++ b/runtime/openjdkjvmti/art_jvmti.h
@@ -37,6 +37,8 @@
 #include <jni.h>
 
 #include "base/casts.h"
+#include "base/logging.h"
+#include "base/macros.h"
 #include "events.h"
 #include "java_vm_ext.h"
 #include "jni_env_ext.h"
@@ -80,6 +82,32 @@
   return ret_value;
 }
 
+class JvmtiDeleter {
+ public:
+  JvmtiDeleter() : env_(nullptr) {}
+  explicit JvmtiDeleter(jvmtiEnv* env) : env_(env) {}
+
+  JvmtiDeleter(JvmtiDeleter&) = default;
+  JvmtiDeleter(JvmtiDeleter&&) = default;
+  JvmtiDeleter& operator=(const JvmtiDeleter&) = default;
+
+  void operator()(unsigned char* ptr) const {
+    CHECK(env_ != nullptr);
+    jvmtiError ret = env_->Deallocate(ptr);
+    CHECK(ret == ERR(NONE));
+  }
+
+ private:
+  mutable jvmtiEnv* env_;
+};
+
+using JvmtiUniquePtr = std::unique_ptr<unsigned char, JvmtiDeleter>;
+
+ALWAYS_INLINE
+static inline JvmtiUniquePtr MakeJvmtiUniquePtr(jvmtiEnv* env, unsigned char* mem) {
+  return JvmtiUniquePtr(mem, JvmtiDeleter(env));
+}
+
 }  // namespace openjdkjvmti
 
 #endif  // ART_RUNTIME_OPENJDKJVMTI_ART_JVMTI_H_
diff --git a/runtime/openjdkjvmti/ti_method.cc b/runtime/openjdkjvmti/ti_method.cc
new file mode 100644
index 0000000..8d943d9
--- /dev/null
+++ b/runtime/openjdkjvmti/ti_method.cc
@@ -0,0 +1,100 @@
+/* Copyright (C) 2016 The Android Open Source Project
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This file implements interfaces from the file jvmti.h. This implementation
+ * is licensed under the same terms as the file jvmti.h.  The
+ * copyright and license information for the file jvmti.h follows.
+ *
+ * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "ti_method.h"
+
+#include "art_jvmti.h"
+#include "art_method-inl.h"
+#include "base/enums.h"
+#include "scoped_thread_state_change-inl.h"
+
+namespace openjdkjvmti {
+
+static jvmtiError CopyString(jvmtiEnv* env, const char* src, unsigned char** copy) {
+  size_t len = strlen(src) + 1;
+  unsigned char* buf;
+  jvmtiError ret = env->Allocate(len, &buf);
+  if (ret != ERR(NONE)) {
+    return ret;
+  }
+  strcpy(reinterpret_cast<char*>(buf), src);
+  *copy = buf;
+  return ret;
+}
+
+jvmtiError MethodUtil::GetMethodName(jvmtiEnv* env,
+                                     jmethodID method,
+                                     char** name_ptr,
+                                     char** signature_ptr,
+                                     char** generic_ptr) {
+  art::ScopedObjectAccess soa(art::Thread::Current());
+  art::ArtMethod* art_method = soa.DecodeMethod(method);
+  art_method = art_method->GetInterfaceMethodIfProxy(art::kRuntimePointerSize);
+
+  JvmtiUniquePtr name_copy;
+  if (name_ptr != nullptr) {
+    const char* method_name = art_method->GetName();
+    if (method_name == nullptr) {
+      method_name = "<error>";
+    }
+    unsigned char* tmp;
+    jvmtiError ret = CopyString(env, method_name, &tmp);
+    if (ret != ERR(NONE)) {
+      return ret;
+    }
+    name_copy = MakeJvmtiUniquePtr(env, tmp);
+    *name_ptr = reinterpret_cast<char*>(tmp);
+  }
+
+  JvmtiUniquePtr signature_copy;
+  if (signature_ptr != nullptr) {
+    const art::Signature sig = art_method->GetSignature();
+    std::string str = sig.ToString();
+    unsigned char* tmp;
+    jvmtiError ret = CopyString(env, str.c_str(), &tmp);
+    if (ret != ERR(NONE)) {
+      return ret;
+    }
+    signature_copy = MakeJvmtiUniquePtr(env, tmp);
+    *signature_ptr = reinterpret_cast<char*>(tmp);
+  }
+
+  // TODO: Support generic signature.
+  *generic_ptr = nullptr;
+
+  // Everything is fine, release the buffers.
+  name_copy.release();
+  signature_copy.release();
+
+  return ERR(NONE);
+}
+
+}  // namespace openjdkjvmti
diff --git a/runtime/openjdkjvmti/ti_method.h b/runtime/openjdkjvmti/ti_method.h
new file mode 100644
index 0000000..17a3728
--- /dev/null
+++ b/runtime/openjdkjvmti/ti_method.h
@@ -0,0 +1,51 @@
+/* Copyright (C) 2016 The Android Open Source Project
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This file implements interfaces from the file jvmti.h. This implementation
+ * is licensed under the same terms as the file jvmti.h.  The
+ * copyright and license information for the file jvmti.h follows.
+ *
+ * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#ifndef ART_RUNTIME_OPENJDKJVMTI_TI_METHOD_H_
+#define ART_RUNTIME_OPENJDKJVMTI_TI_METHOD_H_
+
+#include "jni.h"
+#include "jvmti.h"
+
+namespace openjdkjvmti {
+
+class MethodUtil {
+ public:
+  static jvmtiError GetMethodName(jvmtiEnv* env,
+                                  jmethodID method,
+                                  char** name_ptr,
+                                  char** signature_ptr,
+                                  char** generic_ptr);
+};
+
+}  // namespace openjdkjvmti
+
+#endif  // ART_RUNTIME_OPENJDKJVMTI_TI_METHOD_H_