1 /*
2 * Copyright (c) 2016, 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
28 #ifdef __cplusplus
29 extern "C" {
30 #endif
31
32 #ifndef JNI_ENV_ARG
33
34 #ifdef __cplusplus
35 #define JNI_ENV_ARG(x, y) y
36 #define JNI_ENV_PTR(x) x
37 #else
38 #define JNI_ENV_ARG(x,y) x, y
39 #define JNI_ENV_PTR(x) (*x)
40 #endif
41
42 #endif
43
44 #define TranslateError(err) "JVMTI error"
45
46 #define PASSED 0
47 #define FAILED 2
48
49 static const char *EXPECTED_SIGNATURE = "Ljava/util/Collections;";
50 static const char *EXC_CNAME = "java/lang/Exception";
51
52 static jvmtiEnv *jvmti = NULL;
53 static jint result = PASSED;
54 static jboolean printdump = JNI_FALSE;
55
56 static jboolean with_early_vm_start_capability = JNI_FALSE;
57
58 static jboolean class_in_class_load_events_vm_start = JNI_FALSE;
59 static jboolean class_in_class_load_events_vm_live = JNI_FALSE;
60 static jboolean class_in_class_prepare_events_vm_start = JNI_FALSE;
61 static jboolean class_in_class_prepare_events_vm_live = JNI_FALSE;
62
63 static int class_load_events_vm_start_count = 0;
64 static int class_prepare_events_vm_start_count = 0;
65
66 static jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved);
67
68 JNIEXPORT
69 jint JNICALL Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
70 return Agent_Initialize(jvm, options, reserved);
71 }
72
73 JNIEXPORT
74 jint JNICALL Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
75 return Agent_Initialize(jvm, options, reserved);
76 }
77
78 JNIEXPORT
79 jint JNICALL JNI_OnLoad(JavaVM *jvm, void *reserved) {
80 return JNI_VERSION_9;
81 }
82
83 static
84 jint throw_exc(JNIEnv *env, char *msg) {
85 jclass exc_class = JNI_ENV_PTR(env)->FindClass(JNI_ENV_ARG(env, EXC_CNAME));
86
87 if (exc_class == NULL) {
88 printf("throw_exc: Error in FindClass(env, %s)\n", EXC_CNAME);
89 return -1;
90 }
91 return JNI_ENV_PTR(env)->ThrowNew(JNI_ENV_ARG(env, exc_class), msg);
92 }
93
94 static void JNICALL
95 Callback_ClassFileLoad(jvmtiEnv *jvmti_env, JNIEnv *env, jthread thread, jclass klass) {
96 jvmtiPhase phase;
97 char *sig, *generic;
98 jvmtiError err;
99
100 err = (*jvmti)->GetPhase(jvmti_env,&phase);
101 if (err != JVMTI_ERROR_NONE) {
102 printf("ClassLoad event: GetPhase error: %s (%d)\n", TranslateError(err), err);
103 result = FAILED;
104 return;
105 }
106
107 if (phase == JVMTI_PHASE_START || phase == JVMTI_PHASE_LIVE) {
108
109 err = (*jvmti)->GetClassSignature(jvmti_env, klass, &sig, &generic);
110
111 if (err != JVMTI_ERROR_NONE) {
112 printf("ClassLoad event: GetClassSignature error: %s (%d)\n", TranslateError(err), err);
113 result = FAILED;
114 return;
115 }
116
117 if (phase == JVMTI_PHASE_START) {
118 class_load_events_vm_start_count++;
119 if(!strcmp(sig, EXPECTED_SIGNATURE)) {
120 class_in_class_load_events_vm_start = JNI_TRUE;
121 }
122 } else {
123 if(!strcmp(sig, EXPECTED_SIGNATURE)) {
124 class_in_class_load_events_vm_live = JNI_TRUE;
125 }
126 }
127
128 if (printdump == JNI_TRUE) {
129 printf(">>> ClassLoad event: phase(%d), class signature %s\n", phase, sig == NULL ? "null": sig);
130 }
131 } else {
132 printf("ClassLoad event: get event in unexpected phase(%d)\n", phase);
133 result = FAILED;
134 }
135 }
136
137 static void JNICALL
138 Callback_ClassFilePrepare(jvmtiEnv *jvmti_env, JNIEnv *env, jthread thread, jclass klass) {
139 jvmtiPhase phase;
140 char *sig, *generic;
141 jvmtiError err;
142
143 err = (*jvmti)->GetPhase(jvmti_env,&phase);
144 if (err != JVMTI_ERROR_NONE) {
145 printf("ClassPrepare event: GetPhase error: %s (%d)\n", TranslateError(err), err);
146 result = FAILED;
147 return;
148 }
149
150 if (phase == JVMTI_PHASE_START || phase == JVMTI_PHASE_LIVE) {
151
152 err = (*jvmti)->GetClassSignature(jvmti_env, klass, &sig, &generic);
153
154 if (err != JVMTI_ERROR_NONE) {
155 printf("ClassPrepare event: GetClassSignature error: %s (%d)\n", TranslateError(err), err);
156 result = FAILED;
157 return;
158 }
159
160 if (phase == JVMTI_PHASE_START) {
161 class_prepare_events_vm_start_count++;
162 if(!strcmp(sig, EXPECTED_SIGNATURE)) {
163 class_in_class_prepare_events_vm_start = JNI_TRUE;
164 }
165 } else {
166 if(!strcmp(sig, EXPECTED_SIGNATURE)) {
167 class_in_class_prepare_events_vm_live = JNI_TRUE;
168 }
169 }
170
171 if (printdump == JNI_TRUE) {
172 printf(">>> ClassPrepare event: phase(%d), class signature %s\n", phase, sig == NULL ? "null": sig);
173 }
174 } else {
175 printf("ClassPrepare event: get event in unexpected phase(%d)\n", phase);
176 result = FAILED;
177 }
178 }
179
180 static
181 jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
182 jint res, size;
183 jvmtiCapabilities caps;
184 jvmtiEventCallbacks callbacks;
185 jvmtiError err;
186
187 if (options != NULL) {
188 if (strstr(options, "with_early_vmstart") != NULL) {
189 with_early_vm_start_capability = JNI_TRUE;
190 }
191 if (strstr(options, "printdump") != NULL) {
192 printdump = JNI_TRUE;
193 }
194 }
195
196 res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti),
197 JVMTI_VERSION_9);
198 if (res != JNI_OK || jvmti == NULL) {
199 printf(" Error: wrong result of a valid call to GetEnv!\n");
200 return JNI_ERR;
201 }
202
203 if (with_early_vm_start_capability == JNI_TRUE) {
204 printf("Enabling following capability: can_generate_early_vmstart\n");
205 memset(&caps, 0, sizeof(caps));
206 caps.can_generate_early_vmstart = 1;
207
208 err = (*jvmti)->AddCapabilities(jvmti, &caps);
209 if (err != JVMTI_ERROR_NONE) {
210 printf(" Error in AddCapabilites: %s (%d)\n", TranslateError(err), err);
211 return JNI_ERR;
212 }
213 }
214
215 size = (jint)sizeof(callbacks);
216
217 memset(&callbacks, 0, sizeof(callbacks));
218 callbacks.ClassLoad = Callback_ClassFileLoad;
219 callbacks.ClassPrepare = Callback_ClassFilePrepare;
220
221 err = (*jvmti)->SetEventCallbacks(jvmti, &callbacks, size);
222 if (err != JVMTI_ERROR_NONE) {
223 printf(" Error in SetEventCallbacks: %s (%d)\n", TranslateError(err), err);
224 return JNI_ERR;
225 }
226
227 err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE, JVMTI_EVENT_CLASS_LOAD, NULL);
228 if (err != JVMTI_ERROR_NONE) {
229 printf(" Error in SetEventNotificationMode: %s (%d)\n", TranslateError(err), err);
230 return JNI_ERR;
231 }
232
233 err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE, JVMTI_EVENT_CLASS_PREPARE, NULL);
234
235 if (err != JVMTI_ERROR_NONE) {
236 printf(" Error in SetEventNotificationMode: %s (%d)\n", TranslateError(err), err);
237 return JNI_ERR;
238 }
239
240 return JNI_OK;
241 }
242
243 JNIEXPORT jint JNICALL
244 Java_MAAClassLoadPrepare_check(JNIEnv *env, jclass cls) {
245 jobject loader = NULL;
246
247 if (jvmti == NULL) {
248 throw_exc(env, "JVMTI client was not properly loaded!\n");
249 return FAILED;
250 }
251
252 if (with_early_vm_start_capability == JNI_TRUE) {
253 /*
254 * Expecting that "java/util/Collections" class from java.base module is present in the
255 * ClassLoad and ClassPrepare events during VM Start phase when can_generate_early_vmstart
256 * capability is enabled
257 * Expecting that ClassLoad and ClassPrepare events are sent in th
258 * VM Start phase when can_generate_early_vmstart is enabled(JDK-8165681)
259 */
260 if (class_load_events_vm_start_count == 0) {
261 throw_exc(env, "Didn't get ClassLoad events in start phase!\n");
262 return FAILED;
263 }
264
265 printf("Expecting to find '%s' class in ClassLoad events during VM start phase.\n", EXPECTED_SIGNATURE);
266 if (class_in_class_load_events_vm_start == JNI_FALSE) {
267 throw_exc(env, "Unable to find expected class in ClassLoad events during start phase!\n");
268 return FAILED;
269 }
270
271 if (class_prepare_events_vm_start_count == 0) {
272 throw_exc(env, "Didn't get ClassPrepare events in start phase!\n");
273 return FAILED;
274 }
275
276 printf("Expecting to find '%s' class in ClassPrepare events during VM start phase.\n", EXPECTED_SIGNATURE);
277 if (class_in_class_prepare_events_vm_start == JNI_FALSE) {
278 throw_exc(env, "Unable to find expected class in ClassPrepare events during start phase!\n");
279 return FAILED;
280 }
281 } else {
282 /*
283 * Expecting that "java/util/Collections" class from java.base module is not present in the
284 * ClassLoad and ClassPrepare events during VM Start phase when can_generate_early_vmstart
285 * capability is disabled
286 */
287 printf("Expecting that '%s' class is absent in ClassLoad events.\n", EXPECTED_SIGNATURE);
288 if (class_in_class_prepare_events_vm_start == JNI_TRUE) {
289 throw_exc(env, "Class is found in ClassLoad events during VM Start phase!\n");
290 return FAILED;
291 }
292
293 printf("Expecting that '%s' class is absent in ClassPrepare events.\n", EXPECTED_SIGNATURE);
294 if (class_in_class_prepare_events_vm_start == JNI_TRUE) {
295 throw_exc(env, "Class is found in ClassPrepare events during VM Start phase!\n");
296 return FAILED;
297 }
298 }
299
300 /*
301 * In any case, we not expect to see "java/util/Collections" class from java.base module
302 * in the ClassLoad and ClassPrepare events during VM Live phase
303 */
304 if (class_in_class_prepare_events_vm_live == JNI_TRUE) {
305 throw_exc(env, "Class is found in ClassLoad events during VM Live phase!\n");
306 return FAILED;
307 }
308
309 if (class_in_class_prepare_events_vm_live == JNI_TRUE) {
310 throw_exc(env, "Class is found in ClassPrepare events during VM Live phase!\n");
311 return FAILED;
312 }
313
314 return result;
315 }
316
317 #ifdef __cplusplus
318 }
319 #endif