| /* |
| * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include "jvmti.h" |
| #include "jni.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| |
| static jvmtiEnv *jvmti = NULL; |
| |
| // valid while a test is executed |
| static jobject testResultObject = NULL; |
| static jclass testResultClass = NULL; |
| |
| |
| static void reportError(const char *msg, int err) { |
| printf("%s, error: %d\n", msg, err); |
| } |
| |
| |
| // logs the notification and updates currentTestResult |
| static void handleNotification(JNIEnv *jni_env, |
| jmethodID method, |
| jfieldID field, |
| jclass field_klass, |
| int modified, |
| jlocation location) |
| { |
| jvmtiError err; |
| char *name = NULL; |
| char *mname = NULL; |
| char *mgensig = NULL; |
| jclass methodClass = NULL; |
| char *csig = NULL; |
| |
| if (testResultObject == NULL) { |
| // we are out of test |
| return; |
| } |
| |
| err = (*jvmti)->GetFieldName(jvmti, field_klass, field, &name, NULL, NULL); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("GetFieldName failed", err); |
| return; |
| } |
| |
| err = (*jvmti)->GetMethodName(jvmti, method, &mname, NULL, &mgensig); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("GetMethodName failed", err); |
| return; |
| } |
| |
| err = (*jvmti)->GetMethodDeclaringClass(jvmti, method, &methodClass); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("GetMethodDeclaringClass failed", err); |
| return; |
| } |
| |
| err = (*jvmti)->GetClassSignature(jvmti, methodClass, &csig, NULL); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("GetClassSignature failed", err); |
| return; |
| } |
| |
| printf("\"class: %s method: %s%s\" %s field: \"%s\", location: %d\n", |
| csig, mname, mgensig, modified ? "modified" : "accessed", name, (int)location); |
| |
| // set TestResult |
| if (testResultObject != NULL && testResultClass != NULL) { |
| jfieldID fieldID; |
| // field names in TestResult are "<field_name>_access"/"<field_name>_modify" |
| char *fieldName = (char *)malloc(strlen(name) + 16); |
| strcpy(fieldName, name); |
| strcat(fieldName, modified ? "_modify" : "_access"); |
| |
| fieldID = (*jni_env)->GetFieldID(jni_env, testResultClass, fieldName, "Z"); |
| if (fieldID != NULL) { |
| (*jni_env)->SetBooleanField(jni_env, testResultObject, fieldID, JNI_TRUE); |
| } else { |
| // the field is not interesting for the test |
| } |
| // clear any possible exception |
| (*jni_env)->ExceptionClear(jni_env); |
| |
| free(fieldName); |
| } |
| |
| (*jvmti)->Deallocate(jvmti, (unsigned char*)csig); |
| (*jvmti)->Deallocate(jvmti, (unsigned char*)mname); |
| (*jvmti)->Deallocate(jvmti, (unsigned char*)mgensig); |
| (*jvmti)->Deallocate(jvmti, (unsigned char*)name); |
| } |
| |
| // recursively sets access and modification watchers for all |
| // fields of the object specified. |
| void setWatchers(JNIEnv *jni_env, const jobject obj) |
| { |
| jclass klass; |
| |
| if (obj == NULL) { |
| return; |
| } |
| |
| klass = (*jni_env)->GetObjectClass(jni_env, obj); |
| do { |
| jfieldID* klassFields = NULL; |
| jint fieldCount = 0; |
| int i; |
| jvmtiError err = (*jvmti)->GetClassFields(jvmti, klass, &fieldCount, &klassFields); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("Failed to get class fields", err); |
| return; |
| } |
| |
| for (i = 0; i < fieldCount; ++i) { |
| char *sig = NULL; |
| err = (*jvmti)->SetFieldModificationWatch(jvmti, klass, klassFields[i]); |
| if (err != JVMTI_ERROR_NONE && err != JVMTI_ERROR_DUPLICATE) { |
| reportError("Failed to set field modification", err); |
| return; |
| } |
| |
| err = (*jvmti)->SetFieldAccessWatch(jvmti, klass, klassFields[i]); |
| if (err != JVMTI_ERROR_NONE && err != JVMTI_ERROR_DUPLICATE) { |
| reportError("Failed to set field access", err); |
| return; |
| } |
| |
| err = (*jvmti)->GetFieldName(jvmti, klass, klassFields[i], NULL, &sig, NULL); |
| if (sig) { |
| if (sig[0] == 'L') { |
| jobject fieldVal = (*jni_env)->GetObjectField(jni_env, obj, klassFields[i]); |
| setWatchers(jni_env, fieldVal); |
| } |
| (*jvmti)->Deallocate(jvmti, (unsigned char*)sig); |
| } |
| } |
| |
| (*jvmti)->Deallocate(jvmti, (unsigned char*)klassFields); |
| |
| klass = (*jni_env)->GetSuperclass(jni_env, klass); |
| } while (klass != NULL); |
| } |
| |
| |
| static void JNICALL |
| onFieldAccess(jvmtiEnv *jvmti_env, |
| JNIEnv* jni_env, |
| jthread thread, |
| jmethodID method, |
| jlocation location, |
| jclass field_klass, |
| jobject object, |
| jfieldID field) |
| { |
| handleNotification(jni_env, method, field, field_klass, 0, location); |
| } |
| |
| |
| static void JNICALL |
| onFieldModification(jvmtiEnv *jvmti_env, |
| JNIEnv* jni_env, |
| jthread thread, |
| jmethodID method, |
| jlocation location, |
| jclass field_klass, |
| jobject object, |
| jfieldID field, |
| char signature_type, |
| jvalue new_value) |
| { |
| handleNotification(jni_env, method, field, field_klass, 1, location); |
| |
| if (signature_type == 'L') { |
| jobject newObject = new_value.l; |
| setWatchers(jni_env, newObject); |
| } |
| } |
| |
| |
| JNIEXPORT jint JNICALL |
| Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) |
| { |
| jvmtiError err; |
| jvmtiCapabilities caps = {0}; |
| jvmtiEventCallbacks callbacks = {0}; |
| jint res = (*jvm)->GetEnv(jvm, (void **) &jvmti, JVMTI_VERSION_1_1); |
| if (res != JNI_OK || jvmti == NULL) { |
| reportError("GetEnv failed", res); |
| return JNI_ERR; |
| } |
| |
| caps.can_generate_field_modification_events = 1; |
| caps.can_generate_field_access_events = 1; |
| caps.can_tag_objects = 1; |
| err = (*jvmti)->AddCapabilities(jvmti, &caps); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("Failed to set capabilities", err); |
| return JNI_ERR; |
| } |
| |
| callbacks.FieldModification = &onFieldModification; |
| callbacks.FieldAccess = &onFieldAccess; |
| |
| err = (*jvmti)->SetEventCallbacks(jvmti, &callbacks, sizeof(callbacks)); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("Failed to set event callbacks", err); |
| return JNI_ERR; |
| } |
| |
| err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE, JVMTI_EVENT_FIELD_ACCESS, NULL); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("Failed to set access notifications", err); |
| return JNI_ERR; |
| } |
| |
| err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE, JVMTI_EVENT_FIELD_MODIFICATION, NULL); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("Failed to set modification notifications", err); |
| return JNI_ERR; |
| } |
| setbuf(stdout, NULL); |
| return JNI_OK; |
| } |
| |
| |
| JNIEXPORT jboolean JNICALL |
| Java_FieldAccessWatch_initWatchers(JNIEnv *env, jclass thisClass, jclass cls, jobject field) |
| { |
| jfieldID fieldId; |
| jvmtiError err; |
| |
| if (jvmti == NULL) { |
| reportError("jvmti is NULL", 0); |
| return JNI_FALSE; |
| } |
| |
| fieldId = (*env)->FromReflectedField(env, field); |
| |
| err = (*jvmti)->SetFieldModificationWatch(jvmti, cls, fieldId); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("SetFieldModificationWatch failed", err); |
| return JNI_FALSE; |
| } |
| |
| err = (*jvmti)->SetFieldAccessWatch(jvmti, cls, fieldId); |
| if (err != JVMTI_ERROR_NONE) { |
| reportError("SetFieldAccessWatch failed", err); |
| return JNI_FALSE; |
| } |
| |
| return JNI_TRUE; |
| } |
| |
| |
| JNIEXPORT jboolean JNICALL |
| Java_FieldAccessWatch_startTest(JNIEnv *env, jclass thisClass, jobject testResults) |
| { |
| testResultObject = (*env)->NewGlobalRef(env, testResults); |
| testResultClass = (jclass)(*env)->NewGlobalRef(env, (*env)->GetObjectClass(env, testResultObject)); |
| |
| return JNI_TRUE; |
| } |
| |
| JNIEXPORT void JNICALL |
| Java_FieldAccessWatch_stopTest(JNIEnv *env, jclass thisClass) |
| { |
| if (testResultObject != NULL) { |
| (*env)->DeleteGlobalRef(env, testResultObject); |
| testResultObject = NULL; |
| } |
| if (testResultClass != NULL) { |
| (*env)->DeleteGlobalRef(env, testResultClass); |
| testResultClass = NULL; |
| } |
| } |
| |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |