1 /*
 2  * Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 4  *
 5  * This code is free software; you can redistribute it and/or modify it
 6  * under the terms of the GNU General Public License version 2 only, as
 7  * published by the Free Software Foundation.
 8  *
 9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 
24 #include <stdio.h>
25 #include <string.h>
26 #include "jvmti.h"
27 #include "jni.h"
28 #include "jvmti_common.hpp"
29 
30 #ifdef __cplusplus
31 extern "C" {
32 #endif
33 
34 static jvmtiEnv *jvmti = nullptr;
35 
36 JNIEXPORT jint JNICALL
37 Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
38   jint res = jvm->GetEnv((void **) &jvmti, JVMTI_VERSION_1_1);
39   if (res != JNI_OK || jvmti == nullptr) {
40     LOG("GetEnv failed, res = %d", (int)res);
41     return JNI_ERR;
42   }
43 
44   jvmtiCapabilities caps;
45   memset(&caps, 0, sizeof(caps));
46   caps.can_access_local_variables = 1;
47   jvmtiError err = jvmti->AddCapabilities(&caps);
48   if (err != JVMTI_ERROR_NONE) {
49     LOG("AddCapabilities failed: %s (%d)\n", TranslateError(err), err);
50     return JNI_ERR;
51   }
52 
53   return JNI_OK;
54 }
55 
56 JNIEXPORT void JNICALL
57 Java_ValueGetSetLocal_testLocals(JNIEnv *jni, jclass thisClass, jthread thread, jboolean testSetLocal) {
58   const jint depth = 1;
59 
60   LOG("\ntestLocals\n");
61   jobject obj0 = get_local_object(jvmti, jni, thread, depth, 0);
62   jobject obj1 = get_local_object(jvmti, jni, thread, depth, 1);
63   jobject obj2 = get_local_object(jvmti, jni, thread, depth, 2);
64   jobject obj3 = get_local_object(jvmti, jni, thread, depth, 3);
65   jobject obj_this = get_local_instance(jvmti, jni, thread, depth);
66 
67   // obj0 is expected to be equal "this"
68   if (!jni->IsSameObject(obj0, obj_this)) {
69     fatal(jni, "Failed: obj0 != obj_this\n");
70   }
71   // obj3 is expected to be equal obj2
72   if (!jni->IsSameObject(obj3, obj2)) {
73     fatal(jni, "Failed: obj3 != obj2\n");
74   }
75 
76   if (testSetLocal) {
77     // set obj3 = obj1
78     set_local_object(jvmti, thread, depth, 3, obj1);
79     obj3 = get_local_object(jvmti, jni, thread, depth, 3);
80     if (!jni->IsSameObject(obj3, obj1)) {
81       fatal(jni, "Failed: obj3 != obj1\n");
82     }
83   }
84 }
85 
86 #ifdef __cplusplus
87 }
88 #endif
89