1/* Copyright (C) 2017 The Android Open Source Project
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This file implements interfaces from the file jvmti.h. This implementation
5 * is licensed under the same terms as the file jvmti.h.  The
6 * copyright and license information for the file jvmti.h follows.
7 *
8 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
9 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
10 *
11 * This code is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License version 2 only, as
13 * published by the Free Software Foundation.  Oracle designates this
14 * particular file as subject to the "Classpath" exception as provided
15 * by Oracle in the LICENSE file that accompanied this code.
16 *
17 * This code is distributed in the hope that it will be useful, but WITHOUT
18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
20 * version 2 for more details (a copy is included in the LICENSE file that
21 * accompanied this code).
22 *
23 * You should have received a copy of the GNU General Public License version
24 * 2 along with this work; if not, write to the Free Software Foundation,
25 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
26 *
27 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
28 * or visit www.oracle.com if you need additional information or have any
29 * questions.
30 */
31
32#include "ti_jni.h"
33
34#include "jni.h"
35
36#include "art_jvmti.h"
37#include "base/mutex.h"
38#include "java_vm_ext.h"
39#include "jni_env_ext.h"
40#include "runtime.h"
41#include "thread-inl.h"
42
43namespace openjdkjvmti {
44
45jvmtiError JNIUtil::SetJNIFunctionTable(jvmtiEnv* env ATTRIBUTE_UNUSED,
46                                        const jniNativeInterface* function_table) {
47  // While we supporting setting null (which will reset the table), the spec says no.
48  if (function_table == nullptr) {
49    return ERR(NULL_POINTER);
50  }
51
52  art::JNIEnvExt::SetTableOverride(function_table);
53  return ERR(NONE);
54}
55
56jvmtiError JNIUtil::GetJNIFunctionTable(jvmtiEnv* env, jniNativeInterface** function_table) {
57  if (function_table == nullptr) {
58    return ERR(NULL_POINTER);
59  }
60
61  // We use the generic JNIEnvExt::GetFunctionTable instead of querying a specific JNIEnv, as
62  // this has to work in the start phase.
63
64  // Figure out which table is current. Conservatively assume check-jni is off.
65  bool check_jni = false;
66  art::Runtime* runtime = art::Runtime::Current();
67  if (runtime != nullptr && runtime->GetJavaVM() != nullptr) {
68    check_jni = runtime->GetJavaVM()->IsCheckJniEnabled();
69  }
70
71  // Get that table.
72  const JNINativeInterface* current_table;
73  {
74    art::MutexLock mu(art::Thread::Current(), *art::Locks::jni_function_table_lock_);
75    current_table = art::JNIEnvExt::GetFunctionTable(check_jni);
76  }
77
78  // Allocate memory and copy the table.
79  unsigned char* data;
80  jvmtiError data_result = env->Allocate(sizeof(JNINativeInterface), &data);
81  if (data_result != ERR(NONE)) {
82    return data_result;
83  }
84  memcpy(data, current_table, sizeof(JNINativeInterface));
85
86  *function_table = reinterpret_cast<JNINativeInterface*>(data);
87
88  return ERR(NONE);
89}
90
91}  // namespace openjdkjvmti
92