1 /*
2 * Copyright (c) 2004, 2024, 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 <string.h>
25 #include "jvmti.h"
26 #include "agent_common.hpp"
27 #include "ExceptionCheckingJniEnv.hpp"
28 #include "jni_tools.hpp"
29 #include "jvmti_tools.hpp"
30
31 extern "C" {
32
33 /* scaffold objects */
34 static jlong timeout = 0;
35
36 #define PATH_TO_NEW_BYTECODE "pathToNewByteCode"
37 #define TESTED_CLASS_NAME "java/lang/Object"
38
39 static jint newClassSize;
40 static unsigned char* newClassBytes;
41
42 static jvmtiClassDefinition classDef;
43
44 /* ============================================================================= */
45
46 int readNewBytecode(jvmtiEnv* jvmti) {
47
48 char filename[256];
49 FILE *bytecode;
50 const char *pathToByteCode = nsk_jvmti_findOptionValue(PATH_TO_NEW_BYTECODE);
51 jint read_bytes;
52
53 if (pathToByteCode)
54 snprintf(filename, sizeof(filename), "%s/%s/%s.class",
55 pathToByteCode, "newclass02", TESTED_CLASS_NAME);
56 else
57 snprintf(filename, sizeof(filename), "%s/%s.class",
58 "newclass02", TESTED_CLASS_NAME);
59
60 NSK_DISPLAY1("Reading new bytecode for java.lang.Object\n\tfile name: %s\n",
61 filename);
62
63 bytecode = fopen(filename, "rb");
64 if (bytecode == nullptr) {
65 NSK_COMPLAIN0("error opening file\n");
66 return NSK_FALSE;
67 }
68
69 fseek(bytecode, 0, SEEK_END);
70 classDef.class_byte_count = ftell(bytecode);
71 rewind(bytecode);
72
73 if (!NSK_JVMTI_VERIFY(jvmti->Allocate(classDef.class_byte_count, &newClassBytes))) {
74 NSK_COMPLAIN0("buffer couldn't be allocated\n");
75 return NSK_FALSE;
76 }
77 classDef.class_bytes = newClassBytes;
78 read_bytes = (jint) fread(newClassBytes, 1,
79 classDef.class_byte_count, bytecode);
80 fclose(bytecode);
81 if (read_bytes != classDef.class_byte_count) {
82 NSK_COMPLAIN0("error reading file\n");
83 return NSK_FALSE;
84 }
85
86 return NSK_TRUE;
87 }
88
89 /* ============================================================================= */
90
91 /** Agent algorithm. */
92 static void JNICALL
93 agentProc(jvmtiEnv* jvmti, JNIEnv* jni, void* arg) {
94
95 ExceptionCheckingJniEnvPtr ec_jni(jni);
96 /*Wait for debuggee to set classes to be redefined nsk_jvmti_waitForSync#4*/
97 NSK_DISPLAY0("Wait for debuggee to set classes to be redefined nsk_jvmti_waitForSync#4\n");
98 if (!nsk_jvmti_waitForSync(timeout))
99 return;
100
101 NSK_DISPLAY1("Find class: %s\n", TESTED_CLASS_NAME);
102 classDef.klass = ec_jni->FindClass(TESTED_CLASS_NAME, TRACE_JNI_CALL);
103 classDef.klass = (jclass) ec_jni->NewGlobalRef(classDef.klass, TRACE_JNI_CALL);
104
105 NSK_DISPLAY0("Redfine class with new byte code\n");
106 NSK_DISPLAY3("class definition:\n\t0x%p, 0x%p:%d\n",
107 classDef.klass,
108 classDef.class_bytes,
109 classDef.class_byte_count);
110 if (nsk_getVerboseMode()) {
111 nsk_printHexBytes(" ", 16, classDef.class_byte_count,
112 classDef.class_bytes);
113 }
114 if (!NSK_JVMTI_VERIFY(jvmti->RedefineClasses(1, &classDef))) {
115 nsk_jvmti_setFailStatus();
116 return;
117 }
118
119 ec_jni->DeleteGlobalRef(classDef.klass, TRACE_JNI_CALL);
120
121 if (!nsk_jvmti_resumeSync())
122 return;
123 }
124
125 /* ============================================================================= */
126
127 /** Agent library initialization. */
128 #ifdef STATIC_BUILD
129 JNIEXPORT jint JNICALL Agent_OnLoad_bi04t002(JavaVM *jvm, char *options, void *reserved) {
130 return Agent_Initialize(jvm, options, reserved);
131 }
132 JNIEXPORT jint JNICALL Agent_OnAttach_bi04t002(JavaVM *jvm, char *options, void *reserved) {
133 return Agent_Initialize(jvm, options, reserved);
134 }
135 JNIEXPORT jint JNI_OnLoad_bi04t002(JavaVM *jvm, char *options, void *reserved) {
136 return JNI_VERSION_1_8;
137 }
138 #endif
139 jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
140 jvmtiEnv *jvmti = nullptr;
141
142 if (!NSK_VERIFY(nsk_jvmti_parseOptions(options)))
143 return JNI_ERR;
144
145 timeout = nsk_jvmti_getWaitTime() * 60 * 1000;
146
147 jvmti = nsk_jvmti_createJVMTIEnv(jvm, reserved);
148 if (!NSK_VERIFY(jvmti != nullptr))
149 return JNI_ERR;
150
151 {
152 jvmtiCapabilities caps;
153 memset(&caps, 0, sizeof(caps));
154
155 caps.can_redefine_classes = 1;
156 caps.can_redefine_any_class = 1;
157 if (!NSK_JVMTI_VERIFY(jvmti->AddCapabilities(&caps)))
158 return JNI_ERR;
159 }
160
161 if (!NSK_VERIFY(readNewBytecode(jvmti)))
162 return JNI_ERR;
163
164 if (!NSK_VERIFY(nsk_jvmti_setAgentProc(agentProc, nullptr)))
165 return JNI_ERR;
166
167 return JNI_OK;
168 }
169
170 /* ============================================================================= */
171
172
173 }