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 "jni/java_vm_ext.h"
39 #include "jni/jni_env_ext.h"
40 #include "runtime.h"
41 #include "thread-current-inl.h"
42
43 namespace openjdkjvmti {
44
SetJNIFunctionTable(jvmtiEnv * env ATTRIBUTE_UNUSED,const jniNativeInterface * function_table)45 jvmtiError 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
GetJNIFunctionTable(jvmtiEnv * env,jniNativeInterface ** function_table)56 jvmtiError 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