1 /*
2 * Copyright (c) 2007, 2019, 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 #include <stdio.h>
24 #include <stdlib.h>
25 #include <jvmti.h>
26 #include "agent_common.h"
27 #include <jni.h>
28 #include <string.h>
29 #include "jvmti_tools.h"
30 #include "jni_tools.h"
31 #include "JVMTITools.h"
32 /*
33 hs203T003:
34 1. Set FieldAccessWatch, FieldModificatoinWatch for a field.
35 2. Upon access/modification of the field within a method, redefine
36 a class with the changed field version, and pop a currently executed
37 frame within FieldAccess/FieldModification callback.
38
39 */
40 extern "C" {
41 #define DIR_NAME "newclass"
42 #define PATH_FORMAT "%s%02d/%s"
43
44 #define FILE_NAME "nsk/jvmti/scenarios/hotswap/HS203/hs203t003/MyThread"
45 #define CLASS_NAME "Lnsk/jvmti/scenarios/hotswap/HS203/hs203t003/MyThread;"
46 #define SEARCH_NAME "nsk/jvmti/scenarios/hotswap/HS203/hs203t003/MyThread"
47 #define FIELDNAME "threadState"
48 #define TYPE "I"
49
50 static jint redefineNumber;
51 static jvmtiEnv * jvmti;
52 static int redefineCnt=0;
53
54 JNIEXPORT void JNICALL callbackClassPrepare(jvmtiEnv *jvmti_env,
55 JNIEnv* jni,
56 jthread thread,
57 jclass klass) {
58 char * className;
59 char * generic;
60 redefineNumber=0;
61 className=NULL;
62 generic=NULL;
63 if (!NSK_JVMTI_VERIFY(jvmti_env->GetClassSignature(klass, &className, &generic))) {
64 nsk_printf("#error Agent :: while getting classname Signature.\n");
65 nsk_jvmti_agentFailed();
66 } else {
67 if (strcmp(className,CLASS_NAME) == 0) {
68 jfieldID field;
69 /* get the field id and set watch on that .*/
70 if (!NSK_JNI_VERIFY(jni, (field = jni->GetFieldID(klass, FIELDNAME, TYPE)) != NULL)) {
71 nsk_printf(" Agent :: (*JNI)->GetFieldID(jni, ...) returns `null`.\n");
72 nsk_jvmti_agentFailed();
73 } else if (!NSK_JVMTI_VERIFY(jvmti_env->SetFieldAccessWatch(klass, field))) {
74 nsk_printf("#error Agent :: occured while jvmti->SetFieldAccessWatch(...) .\n");
75 nsk_jvmti_agentFailed();
76 }
77 }
78 }
79 }
80
81 JNIEXPORT void JNICALL callbackFieldAccess(jvmtiEnv *jvmti_env,
82 JNIEnv* jni,
83 jthread thread,
84 jmethodID method,
85 jlocation location,
86 jclass field_klass,
87 jobject object,
88 jfieldID field) {
89 jclass clas;
90 char fileName[512];
91 if (redefineCnt < 10) {
92 redefineCnt++;
93 return;
94 }
95 redefineNumber=0;
96 if (!NSK_JNI_VERIFY(jni, (clas = jni->FindClass(SEARCH_NAME)) != NULL)) {
97 nsk_printf(" Agent :: (*JNI)->FindClass(jni, %s) returns `null`.\n",SEARCH_NAME);
98 nsk_jvmti_agentFailed();
99 } else {
100 nsk_jvmti_getFileName(redefineNumber, FILE_NAME, fileName,
101 sizeof(fileName)/sizeof(char));
102 if (nsk_jvmti_redefineClass(jvmti_env, clas, fileName) != NSK_TRUE) {
103 nsk_printf(" Agent :: Failed to redefine.\n");
104 nsk_jvmti_agentFailed();
105 } else {
106 nsk_printf(" Agent :: Redefined.\n");
107 nsk_printf(" Agent :: Suspendeding thread.\n");
108 /* pop the current working frame. */
109 if (!NSK_JVMTI_VERIFY(jvmti_env->SuspendThread(thread))) {
110 nsk_printf("#error Agent :: occured suspending Thread.\n");
111 nsk_jvmti_agentFailed();
112 } else {
113 nsk_printf(" Agent :: Succeded in suspending.\n");
114 }
115 }
116 }
117 }
118
119 #ifdef STATIC_BUILD
120 JNIEXPORT jint JNICALL Agent_OnLoad_hs203t003(JavaVM *jvm, char *options, void *reserved) {
121 return Agent_Initialize(jvm, options, reserved);
122 }
123 JNIEXPORT jint JNICALL Agent_OnAttach_hs203t003(JavaVM *jvm, char *options, void *reserved) {
124 return Agent_Initialize(jvm, options, reserved);
125 }
126 JNIEXPORT jint JNI_OnLoad_hs203t003(JavaVM *jvm, char *options, void *reserved) {
127 return JNI_VERSION_1_8;
128 }
129 #endif
130 jint Agent_Initialize(JavaVM *vm, char *options, void *reserved) {
131 if (!NSK_VERIFY(JNI_OK == vm->GetEnv((void **)&jvmti, JVMTI_VERSION_1_1))) {
132 nsk_printf(" Agent :: Could not load JVMTI interface.\n");
133 return JNI_ERR;
134 } else {
135 jvmtiCapabilities caps;
136 jvmtiEventCallbacks eventCallbacks;
137 if (!nsk_jvmti_parseOptions(options)) {
138 nsk_printf("#error Agent :: Failed to parse options.\n");
139 return JNI_ERR;
140 }
141 memset(&caps, 0, sizeof(caps));
142 caps.can_redefine_classes = 1;
143 caps.can_suspend=1;
144 caps.can_pop_frame=1;
145 caps.can_generate_all_class_hook_events=1;
146 caps.can_generate_field_access_events=1;
147 if (!NSK_JVMTI_VERIFY(jvmti->AddCapabilities(&caps))) {
148 nsk_printf("#error Agent :: while adding capabilities.\n");
149 return JNI_ERR;
150 }
151 memset(&eventCallbacks, 0, sizeof(eventCallbacks));
152 eventCallbacks.ClassPrepare =callbackClassPrepare;
153 eventCallbacks.FieldAccess= callbackFieldAccess;
154 if (!NSK_JVMTI_VERIFY(jvmti->SetEventCallbacks(&eventCallbacks, sizeof(eventCallbacks)))) {
155 nsk_printf("#error Agent :: while setting event callbacks.\n");
156 return JNI_ERR;
157 }
158 if ((nsk_jvmti_enableNotification(jvmti,JVMTI_EVENT_CLASS_PREPARE, NULL) == NSK_TRUE) &&
159 (nsk_jvmti_enableNotification(jvmti,JVMTI_EVENT_FIELD_ACCESS, NULL) == NSK_TRUE)) {
160 nsk_printf(" Agent :: Notifications are enabled.\n");
161 } else {
162 nsk_printf("#error Agent :: Eanableing Notifications.\n");
163 return JNI_ERR;
164 }
165 }
166 return JNI_OK;
167 }
168
169 JNIEXPORT jboolean JNICALL
170 Java_nsk_jvmti_scenarios_hotswap_HS203_hs203t003_hs203t003_isSuspended(JNIEnv * jni,
171 jclass clas,
172 jthread thread) {
173 jboolean retvalue;
174 jint state;
175 retvalue = JNI_FALSE;
176 if (!NSK_JVMTI_VERIFY(jvmti->GetThreadState(thread, &state))) {
177 nsk_printf(" Agent :: Error while getting thread state.\n");
178 nsk_jvmti_agentFailed();
179 } else {
180 if (state & JVMTI_THREAD_STATE_SUSPENDED) {
181 retvalue = JNI_TRUE;
182 }
183 }
184 return retvalue;
185 }
186
187 JNIEXPORT jboolean JNICALL
188 Java_nsk_jvmti_scenarios_hotswap_HS203_hs203t003_hs203t003_popThreadFrame(JNIEnv * jni,
189 jclass clas,
190 jthread thread) {
191 jboolean retvalue;
192 jint state;
193 retvalue = JNI_FALSE;
194 if (!NSK_JVMTI_VERIFY(jvmti->GetThreadState(thread, &state))) {
195 nsk_printf(" Agent :: Error while getting thread state.\n");
196 nsk_jvmti_agentFailed();
197 } else {
198 if (state & JVMTI_THREAD_STATE_SUSPENDED) {
199 if (!NSK_JVMTI_VERIFY(jvmti->PopFrame(thread))) {
200 nsk_printf("#error Agent :: while poping thread's frame.\n");
201 nsk_jvmti_agentFailed();
202 } else {
203 nsk_printf(" Agent :: poped thread frame.\n");
204 if (!NSK_JVMTI_VERIFY(
205 jvmti->SetEventNotificationMode(JVMTI_DISABLE, JVMTI_EVENT_FIELD_ACCESS, NULL))) {
206 nsk_printf("#error Agent :: failed to disable notification JVMTI_EVENT_FIELD ACCESS.\n");
207 nsk_jvmti_agentFailed();
208 } else {
209 nsk_printf(" Agent :: Disabled notification JVMTI_EVENT_FIELD ACCESS. \n");
210 retvalue = JNI_TRUE;
211 }
212 }
213 } else {
214 nsk_printf("#error Agent :: Thread was not suspened.");
215 nsk_jvmti_agentFailed();
216 }
217 }
218 return retvalue;
219 }
220
221 JNIEXPORT jboolean JNICALL
222 Java_nsk_jvmti_scenarios_hotswap_HS203_hs203t003_hs203t003_resumeThread(JNIEnv * jni,
223 jclass clas,
224 jthread thread) {
225 jboolean retvalue;
226 retvalue = JNI_FALSE;
227 if (!NSK_JVMTI_VERIFY(jvmti->ResumeThread(thread))) {
228 nsk_printf("#error Agent :: while resuming thread.\n");
229 nsk_jvmti_agentFailed();
230 } else {
231 nsk_printf(" Agent :: Thread resumed.\n");
232 retvalue= JNI_TRUE;
233 }
234 return retvalue;
235 }
236
237 }