Java example source code file (JPLISAgent.c)
The JPLISAgent.c Java example source code
/*
* Copyright (c) 2003, 2011, 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* 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.
*/
/*
* Copyright 2003 Wily Technology, Inc.
*/
#include <jni.h>
#include <jvmti.h>
#include <stdlib.h>
#include <string.h>
#include "JPLISAgent.h"
#include "JPLISAssert.h"
#include "Utilities.h"
#include "Reentrancy.h"
#include "JavaExceptions.h"
#include "EncodingSupport.h"
#include "FileSystemSupport.h" /* For MAXPATHLEN & uintptr_t */
#include "sun_instrument_InstrumentationImpl.h"
/*
* The JPLISAgent manages the initialization all of the Java programming language Agents.
* It also supports the native method bridge between the JPLIS and the JVMTI.
* It maintains a single JVMTI Env that all JPL agents share.
* It parses command line requests and creates individual Java agents.
*/
/*
* private prototypes
*/
/* Allocates an unformatted JPLIS agent data structure. Returns NULL if allocation fails. */
JPLISAgent *
allocateJPLISAgent(jvmtiEnv * jvmtiEnv);
/* Initializes an already-allocated JPLIS agent data structure. */
JPLISInitializationError
initializeJPLISAgent( JPLISAgent * agent,
JavaVM * vm,
jvmtiEnv * jvmtienv);
/* De-allocates a JPLIS agent data structure. Only used in partial-failure cases at startup;
* in normal usage the JPLIS agent lives forever
*/
void
deallocateJPLISAgent( jvmtiEnv * jvmtienv,
JPLISAgent * agent);
/* Does one-time work to interrogate the JVM about capabilities and cache the answers. */
void
checkCapabilities(JPLISAgent * agent);
/* Takes the elements of the command string (agent class name and options string) and
* create java strings for them.
* Returns true if a classname was found. Makes no promises beyond the textual; says nothing about whether
* the class exists or can be loaded.
* If return value is true, sets outputClassname to a non-NULL local JNI reference.
* If return value is true, sets outputOptionsString either to NULL or to a non-NULL local JNI reference.
* If return value is false, neither output parameter is set.
*/
jboolean
commandStringIntoJavaStrings( JNIEnv * jnienv,
const char * classname,
const char * optionsString,
jstring * outputClassname,
jstring * outputOptionsString);
/* Start one Java agent from the supplied parameters.
* Most of the logic lives in a helper function that lives over in Java code--
* we pass parameters out to Java and use our own Java helper to actually
* load the agent and call the premain.
* Returns true if the Java agent class is loaded and the premain/agentmain method completes
* with no exceptions, false otherwise.
*/
jboolean
invokeJavaAgentMainMethod( JNIEnv * jnienv,
jobject instrumentationImpl,
jmethodID agentMainMethod,
jstring className,
jstring optionsString);
/* Once we have loaded the Java agent and called the premain,
* we can release the copies we have been keeping of the command line
* data (agent class name and option strings).
*/
void
deallocateCommandLineData(JPLISAgent * agent);
/*
* Common support for various class list fetchers.
*/
typedef jvmtiError (*ClassListFetcher)
( jvmtiEnv * jvmtiEnv,
jobject classLoader,
jint * classCount,
jclass ** classes);
/* Fetcher that ignores the class loader parameter, and uses the JVMTI to get a list of all classes.
* Returns a jvmtiError according to the underlying JVMTI service.
*/
jvmtiError
getAllLoadedClassesClassListFetcher( jvmtiEnv * jvmtiEnv,
jobject classLoader,
jint * classCount,
jclass ** classes);
/* Fetcher that uses the class loader parameter, and uses the JVMTI to get a list of all classes
* for which the supplied loader is the initiating loader.
* Returns a jvmtiError according to the underlying JVMTI service.
*/
jvmtiError
getInitiatedClassesClassListFetcher( jvmtiEnv * jvmtiEnv,
jobject classLoader,
jint * classCount,
jclass ** classes);
/*
* Common guts for two native methods, which are the same except for the policy for fetching
* the list of classes.
* Either returns a local JNI reference to an array of references to java.lang.Class.
* Can throw, if it does will alter the JNIEnv with an outstanding exception.
*/
jobjectArray
commonGetClassList( JNIEnv * jnienv,
JPLISAgent * agent,
jobject classLoader,
ClassListFetcher fetcher);
/*
* Misc. utilities.
*/
/* Checked exception mapper used by the redefine classes implementation.
* Allows ClassNotFoundException or UnmodifiableClassException; maps others
* to InternalError. Can return NULL in an error case.
*/
jthrowable
redefineClassMapper( JNIEnv * jnienv,
jthrowable throwableToMap);
/* Turns a buffer of jclass * into a Java array whose elements are java.lang.Class.
* Can throw, if it does will alter the JNIEnv with an outstanding exception.
*/
jobjectArray
getObjectArrayFromClasses(JNIEnv* jnienv, jclass* classes, jint classCount);
JPLISEnvironment *
getJPLISEnvironment(jvmtiEnv * jvmtienv) {
JPLISEnvironment * environment = NULL;
jvmtiError jvmtierror = JVMTI_ERROR_NONE;
jvmtierror = (*jvmtienv)->GetEnvironmentLocalStorage(
jvmtienv,
(void**)&environment);
/* can be called from any phase */
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
if (jvmtierror == JVMTI_ERROR_NONE) {
jplis_assert(environment != NULL);
jplis_assert(environment->mJVMTIEnv == jvmtienv);
} else {
environment = NULL;
}
return environment;
}
/*
* OnLoad processing code.
*/
/*
* Creates a new JPLISAgent.
* Returns error if the agent cannot be created and initialized.
* The JPLISAgent* pointed to by agent_ptr is set to the new broker,
* or NULL if an error has occurred.
*/
JPLISInitializationError
createNewJPLISAgent(JavaVM * vm, JPLISAgent **agent_ptr) {
JPLISInitializationError initerror = JPLIS_INIT_ERROR_NONE;
jvmtiEnv * jvmtienv = NULL;
jint jnierror = JNI_OK;
*agent_ptr = NULL;
jnierror = (*vm)->GetEnv( vm,
(void **) &jvmtienv,
JVMTI_VERSION_1_1);
if ( jnierror != JNI_OK ) {
initerror = JPLIS_INIT_ERROR_CANNOT_CREATE_NATIVE_AGENT;
} else {
JPLISAgent * agent = allocateJPLISAgent(jvmtienv);
if ( agent == NULL ) {
initerror = JPLIS_INIT_ERROR_ALLOCATION_FAILURE;
} else {
initerror = initializeJPLISAgent( agent,
vm,
jvmtienv);
if ( initerror == JPLIS_INIT_ERROR_NONE ) {
*agent_ptr = agent;
} else {
deallocateJPLISAgent(jvmtienv, agent);
}
}
/* don't leak envs */
if ( initerror != JPLIS_INIT_ERROR_NONE ) {
jvmtiError jvmtierror = (*jvmtienv)->DisposeEnvironment(jvmtienv);
/* can be called from any phase */
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
}
return initerror;
}
/*
* Allocates a JPLISAgent. Returns NULL if it cannot be allocated
*/
JPLISAgent *
allocateJPLISAgent(jvmtiEnv * jvmtienv) {
return (JPLISAgent *) allocate( jvmtienv,
sizeof(JPLISAgent));
}
JPLISInitializationError
initializeJPLISAgent( JPLISAgent * agent,
JavaVM * vm,
jvmtiEnv * jvmtienv) {
jvmtiError jvmtierror = JVMTI_ERROR_NONE;
jvmtiPhase phase;
agent->mJVM = vm;
agent->mNormalEnvironment.mJVMTIEnv = jvmtienv;
agent->mNormalEnvironment.mAgent = agent;
agent->mNormalEnvironment.mIsRetransformer = JNI_FALSE;
agent->mRetransformEnvironment.mJVMTIEnv = NULL; /* NULL until needed */
agent->mRetransformEnvironment.mAgent = agent;
agent->mRetransformEnvironment.mIsRetransformer = JNI_FALSE; /* JNI_FALSE until mJVMTIEnv is set */
agent->mAgentmainCaller = NULL;
agent->mInstrumentationImpl = NULL;
agent->mPremainCaller = NULL;
agent->mTransform = NULL;
agent->mRedefineAvailable = JNI_FALSE; /* assume no for now */
agent->mRedefineAdded = JNI_FALSE;
agent->mNativeMethodPrefixAvailable = JNI_FALSE; /* assume no for now */
agent->mNativeMethodPrefixAdded = JNI_FALSE;
agent->mAgentClassName = NULL;
agent->mOptionsString = NULL;
/* make sure we can recover either handle in either direction.
* the agent has a ref to the jvmti; make it mutual
*/
jvmtierror = (*jvmtienv)->SetEnvironmentLocalStorage(
jvmtienv,
&(agent->mNormalEnvironment));
/* can be called from any phase */
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
/* check what capabilities are available */
checkCapabilities(agent);
/* check phase - if live phase then we don't need the VMInit event */
jvmtierror = (*jvmtienv)->GetPhase(jvmtienv, &phase);
/* can be called from any phase */
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
if (phase == JVMTI_PHASE_LIVE) {
return JPLIS_INIT_ERROR_NONE;
}
if (phase != JVMTI_PHASE_ONLOAD) {
/* called too early or called too late; either way bail out */
return JPLIS_INIT_ERROR_FAILURE;
}
/* now turn on the VMInit event */
if ( jvmtierror == JVMTI_ERROR_NONE ) {
jvmtiEventCallbacks callbacks;
memset(&callbacks, 0, sizeof(callbacks));
callbacks.VMInit = &eventHandlerVMInit;
jvmtierror = (*jvmtienv)->SetEventCallbacks( jvmtienv,
&callbacks,
sizeof(callbacks));
check_phase_ret_blob(jvmtierror, JPLIS_INIT_ERROR_FAILURE);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
if ( jvmtierror == JVMTI_ERROR_NONE ) {
jvmtierror = (*jvmtienv)->SetEventNotificationMode(
jvmtienv,
JVMTI_ENABLE,
JVMTI_EVENT_VM_INIT,
NULL /* all threads */);
check_phase_ret_blob(jvmtierror, JPLIS_INIT_ERROR_FAILURE);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
return (jvmtierror == JVMTI_ERROR_NONE)? JPLIS_INIT_ERROR_NONE : JPLIS_INIT_ERROR_FAILURE;
}
void
deallocateJPLISAgent(jvmtiEnv * jvmtienv, JPLISAgent * agent) {
deallocate(jvmtienv, agent);
}
JPLISInitializationError
recordCommandLineData( JPLISAgent * agent,
const char * agentClassName,
const char * optionsString ) {
JPLISInitializationError initerror = JPLIS_INIT_ERROR_NONE;
char * ourCopyOfAgentClassName = NULL;
char * ourCopyOfOptionsString = NULL;
/* if no actual params, bail out now */
if ((agentClassName == NULL) || (*agentClassName == 0)) {
initerror = JPLIS_INIT_ERROR_AGENT_CLASS_NOT_SPECIFIED;
} else {
ourCopyOfAgentClassName = allocate(jvmti(agent), strlen(agentClassName)+1);
if (ourCopyOfAgentClassName == NULL) {
initerror = JPLIS_INIT_ERROR_ALLOCATION_FAILURE;
} else {
if (optionsString != NULL) {
ourCopyOfOptionsString = allocate(jvmti(agent), strlen(optionsString)+1);
if (ourCopyOfOptionsString == NULL) {
deallocate(jvmti(agent), ourCopyOfAgentClassName);
initerror = JPLIS_INIT_ERROR_ALLOCATION_FAILURE;
}
}
}
}
if (initerror == JPLIS_INIT_ERROR_NONE) {
strcpy(ourCopyOfAgentClassName, agentClassName);
if (optionsString != NULL) {
strcpy(ourCopyOfOptionsString, optionsString);
}
agent->mAgentClassName = ourCopyOfAgentClassName;
agent->mOptionsString = ourCopyOfOptionsString;
}
return initerror;
}
/*
* VMInit processing code.
*/
/*
* If this call fails, the JVM launch will ultimately be aborted,
* so we don't have to be super-careful to clean up in partial failure
* cases.
*/
jboolean
processJavaStart( JPLISAgent * agent,
JNIEnv * jnienv) {
jboolean result;
/*
* OK, Java is up now. We can start everything that needs Java.
*/
/*
* First make our emergency fallback InternalError throwable.
*/
result = initializeFallbackError(jnienv);
jplis_assert(result);
/*
* Now make the InstrumentationImpl instance.
*/
if ( result ) {
result = createInstrumentationImpl(jnienv, agent);
jplis_assert(result);
}
/*
* Then turn off the VMInit handler and turn on the ClassFileLoadHook.
* This way it is on before anyone registers a transformer.
*/
if ( result ) {
result = setLivePhaseEventHandlers(agent);
jplis_assert(result);
}
/*
* Load the Java agent, and call the premain.
*/
if ( result ) {
result = startJavaAgent(agent, jnienv,
agent->mAgentClassName, agent->mOptionsString,
agent->mPremainCaller);
}
/*
* Finally surrender all of the tracking data that we don't need any more.
* If something is wrong, skip it, we will be aborting the JVM anyway.
*/
if ( result ) {
deallocateCommandLineData(agent);
}
return result;
}
jboolean
startJavaAgent( JPLISAgent * agent,
JNIEnv * jnienv,
const char * classname,
const char * optionsString,
jmethodID agentMainMethod) {
jboolean success = JNI_FALSE;
jstring classNameObject = NULL;
jstring optionsStringObject = NULL;
success = commandStringIntoJavaStrings( jnienv,
classname,
optionsString,
&classNameObject,
&optionsStringObject);
if (success) {
success = invokeJavaAgentMainMethod( jnienv,
agent->mInstrumentationImpl,
agentMainMethod,
classNameObject,
optionsStringObject);
}
return success;
}
void
deallocateCommandLineData( JPLISAgent * agent) {
deallocate(jvmti(agent), (void*)agent->mAgentClassName);
deallocate(jvmti(agent), (void*)agent->mOptionsString);
/* zero things out so it is easier to see what is going on */
agent->mAgentClassName = NULL;
agent->mOptionsString = NULL;
}
/*
* Create the java.lang.instrument.Instrumentation instance
* and access information for it (method IDs, etc)
*/
jboolean
createInstrumentationImpl( JNIEnv * jnienv,
JPLISAgent * agent) {
jclass implClass = NULL;
jboolean errorOutstanding = JNI_FALSE;
jobject resultImpl = NULL;
jmethodID premainCallerMethodID = NULL;
jmethodID agentmainCallerMethodID = NULL;
jmethodID transformMethodID = NULL;
jmethodID constructorID = NULL;
jobject localReference = NULL;
/* First find the class of our implementation */
implClass = (*jnienv)->FindClass( jnienv,
JPLIS_INSTRUMENTIMPL_CLASSNAME);
errorOutstanding = checkForAndClearThrowable(jnienv);
errorOutstanding = errorOutstanding || (implClass == NULL);
jplis_assert_msg(!errorOutstanding, "find class on InstrumentationImpl failed");
if ( !errorOutstanding ) {
constructorID = (*jnienv)->GetMethodID( jnienv,
implClass,
JPLIS_INSTRUMENTIMPL_CONSTRUCTOR_METHODNAME,
JPLIS_INSTRUMENTIMPL_CONSTRUCTOR_METHODSIGNATURE);
errorOutstanding = checkForAndClearThrowable(jnienv);
errorOutstanding = errorOutstanding || (constructorID == NULL);
jplis_assert_msg(!errorOutstanding, "find constructor on InstrumentationImpl failed");
}
if ( !errorOutstanding ) {
jlong peerReferenceAsScalar = (jlong)(intptr_t) agent;
localReference = (*jnienv)->NewObject( jnienv,
implClass,
constructorID,
peerReferenceAsScalar,
agent->mRedefineAdded,
agent->mNativeMethodPrefixAdded);
errorOutstanding = checkForAndClearThrowable(jnienv);
errorOutstanding = errorOutstanding || (localReference == NULL);
jplis_assert_msg(!errorOutstanding, "call constructor on InstrumentationImpl failed");
}
if ( !errorOutstanding ) {
resultImpl = (*jnienv)->NewGlobalRef(jnienv, localReference);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "copy local ref to global ref");
}
/* Now look up the method ID for the pre-main caller (we will need this more than once) */
if ( !errorOutstanding ) {
premainCallerMethodID = (*jnienv)->GetMethodID( jnienv,
implClass,
JPLIS_INSTRUMENTIMPL_PREMAININVOKER_METHODNAME,
JPLIS_INSTRUMENTIMPL_PREMAININVOKER_METHODSIGNATURE);
errorOutstanding = checkForAndClearThrowable(jnienv);
errorOutstanding = errorOutstanding || (premainCallerMethodID == NULL);
jplis_assert_msg(!errorOutstanding, "can't find premain invoker methodID");
}
/* Now look up the method ID for the agent-main caller */
if ( !errorOutstanding ) {
agentmainCallerMethodID = (*jnienv)->GetMethodID( jnienv,
implClass,
JPLIS_INSTRUMENTIMPL_AGENTMAININVOKER_METHODNAME,
JPLIS_INSTRUMENTIMPL_AGENTMAININVOKER_METHODSIGNATURE);
errorOutstanding = checkForAndClearThrowable(jnienv);
errorOutstanding = errorOutstanding || (agentmainCallerMethodID == NULL);
jplis_assert_msg(!errorOutstanding, "can't find agentmain invoker methodID");
}
/* Now look up the method ID for the transform method (we will need this constantly) */
if ( !errorOutstanding ) {
transformMethodID = (*jnienv)->GetMethodID( jnienv,
implClass,
JPLIS_INSTRUMENTIMPL_TRANSFORM_METHODNAME,
JPLIS_INSTRUMENTIMPL_TRANSFORM_METHODSIGNATURE);
errorOutstanding = checkForAndClearThrowable(jnienv);
errorOutstanding = errorOutstanding || (transformMethodID == NULL);
jplis_assert_msg(!errorOutstanding, "can't find transform methodID");
}
if ( !errorOutstanding ) {
agent->mInstrumentationImpl = resultImpl;
agent->mPremainCaller = premainCallerMethodID;
agent->mAgentmainCaller = agentmainCallerMethodID;
agent->mTransform = transformMethodID;
}
return !errorOutstanding;
}
jboolean
commandStringIntoJavaStrings( JNIEnv * jnienv,
const char * classname,
const char * optionsString,
jstring * outputClassname,
jstring * outputOptionsString) {
jstring classnameJavaString = NULL;
jstring optionsJavaString = NULL;
jboolean errorOutstanding = JNI_TRUE;
classnameJavaString = (*jnienv)->NewStringUTF(jnienv, classname);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "can't create class name java string");
if ( !errorOutstanding ) {
if ( optionsString != NULL) {
optionsJavaString = (*jnienv)->NewStringUTF(jnienv, optionsString);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "can't create options java string");
}
if ( !errorOutstanding ) {
*outputClassname = classnameJavaString;
*outputOptionsString = optionsJavaString;
}
}
return !errorOutstanding;
}
jboolean
invokeJavaAgentMainMethod( JNIEnv * jnienv,
jobject instrumentationImpl,
jmethodID mainCallingMethod,
jstring className,
jstring optionsString) {
jboolean errorOutstanding = JNI_FALSE;
jplis_assert(mainCallingMethod != NULL);
if ( mainCallingMethod != NULL ) {
(*jnienv)->CallVoidMethod( jnienv,
instrumentationImpl,
mainCallingMethod,
className,
optionsString);
errorOutstanding = checkForThrowable(jnienv);
if ( errorOutstanding ) {
logThrowable(jnienv);
}
checkForAndClearThrowable(jnienv);
}
return !errorOutstanding;
}
jboolean
setLivePhaseEventHandlers( JPLISAgent * agent) {
jvmtiEventCallbacks callbacks;
jvmtiEnv * jvmtienv = jvmti(agent);
jvmtiError jvmtierror;
/* first swap out the handlers (switch from the VMInit handler, which we do not need,
* to the ClassFileLoadHook handler, which is what the agents need from now on)
*/
memset(&callbacks, 0, sizeof(callbacks));
callbacks.ClassFileLoadHook = &eventHandlerClassFileLoadHook;
jvmtierror = (*jvmtienv)->SetEventCallbacks( jvmtienv,
&callbacks,
sizeof(callbacks));
check_phase_ret_false(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
if ( jvmtierror == JVMTI_ERROR_NONE ) {
/* turn off VMInit */
jvmtierror = (*jvmtienv)->SetEventNotificationMode(
jvmtienv,
JVMTI_DISABLE,
JVMTI_EVENT_VM_INIT,
NULL /* all threads */);
check_phase_ret_false(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
if ( jvmtierror == JVMTI_ERROR_NONE ) {
/* turn on ClassFileLoadHook */
jvmtierror = (*jvmtienv)->SetEventNotificationMode(
jvmtienv,
JVMTI_ENABLE,
JVMTI_EVENT_CLASS_FILE_LOAD_HOOK,
NULL /* all threads */);
check_phase_ret_false(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
return (jvmtierror == JVMTI_ERROR_NONE);
}
/**
* Check if the can_redefine_classes capability is available.
*/
void
checkCapabilities(JPLISAgent * agent) {
jvmtiEnv * jvmtienv = jvmti(agent);
jvmtiCapabilities potentialCapabilities;
jvmtiError jvmtierror;
memset(&potentialCapabilities, 0, sizeof(potentialCapabilities));
jvmtierror = (*jvmtienv)->GetPotentialCapabilities(jvmtienv, &potentialCapabilities);
check_phase_ret(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
if ( jvmtierror == JVMTI_ERROR_NONE ) {
if ( potentialCapabilities.can_redefine_classes == 1 ) {
agent->mRedefineAvailable = JNI_TRUE;
}
if ( potentialCapabilities.can_set_native_method_prefix == 1 ) {
agent->mNativeMethodPrefixAvailable = JNI_TRUE;
}
}
}
/**
* Enable native method prefix in one JVM TI environment
*/
void
enableNativeMethodPrefixCapability(jvmtiEnv * jvmtienv) {
jvmtiCapabilities desiredCapabilities;
jvmtiError jvmtierror;
jvmtierror = (*jvmtienv)->GetCapabilities(jvmtienv, &desiredCapabilities);
/* can be called from any phase */
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
desiredCapabilities.can_set_native_method_prefix = 1;
jvmtierror = (*jvmtienv)->AddCapabilities(jvmtienv, &desiredCapabilities);
check_phase_ret(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
/**
* Add the can_set_native_method_prefix capability
*/
void
addNativeMethodPrefixCapability(JPLISAgent * agent) {
if (agent->mNativeMethodPrefixAvailable && !agent->mNativeMethodPrefixAdded) {
jvmtiEnv * jvmtienv = agent->mNormalEnvironment.mJVMTIEnv;
enableNativeMethodPrefixCapability(jvmtienv);
jvmtienv = agent->mRetransformEnvironment.mJVMTIEnv;
if (jvmtienv != NULL) {
enableNativeMethodPrefixCapability(jvmtienv);
}
agent->mNativeMethodPrefixAdded = JNI_TRUE;
}
}
/**
* Add the can_maintain_original_method_order capability (for testing)
*/
void
addOriginalMethodOrderCapability(JPLISAgent * agent) {
jvmtiEnv * jvmtienv = jvmti(agent);
jvmtiCapabilities desiredCapabilities;
jvmtiError jvmtierror;
jvmtierror = (*jvmtienv)->GetCapabilities(jvmtienv, &desiredCapabilities);
/* can be called from any phase */
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
desiredCapabilities.can_maintain_original_method_order = 1;
jvmtierror = (*jvmtienv)->AddCapabilities(jvmtienv, &desiredCapabilities);
check_phase_ret(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
/**
* Add the can_redefine_classes capability
*/
void
addRedefineClassesCapability(JPLISAgent * agent) {
jvmtiEnv * jvmtienv = jvmti(agent);
jvmtiCapabilities desiredCapabilities;
jvmtiError jvmtierror;
if (agent->mRedefineAvailable && !agent->mRedefineAdded) {
jvmtierror = (*jvmtienv)->GetCapabilities(jvmtienv, &desiredCapabilities);
/* can be called from any phase */
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
desiredCapabilities.can_redefine_classes = 1;
jvmtierror = (*jvmtienv)->AddCapabilities(jvmtienv, &desiredCapabilities);
check_phase_ret(jvmtierror);
/*
* With mixed premain/agentmain agents then it's possible that the
* capability was potentially available in the onload phase but
* subsequently unavailable in the live phase.
*/
jplis_assert(jvmtierror == JVMTI_ERROR_NONE ||
jvmtierror == JVMTI_ERROR_NOT_AVAILABLE);
if (jvmtierror == JVMTI_ERROR_NONE) {
agent->mRedefineAdded = JNI_TRUE;
}
}
}
/*
* Support for the JVMTI callbacks
*/
void
transformClassFile( JPLISAgent * agent,
JNIEnv * jnienv,
jobject loaderObject,
const char* name,
jclass classBeingRedefined,
jobject protectionDomain,
jint class_data_len,
const unsigned char* class_data,
jint* new_class_data_len,
unsigned char** new_class_data,
jboolean is_retransformer) {
jboolean errorOutstanding = JNI_FALSE;
jstring classNameStringObject = NULL;
jarray classFileBufferObject = NULL;
jarray transformedBufferObject = NULL;
jsize transformedBufferSize = 0;
unsigned char * resultBuffer = NULL;
jboolean shouldRun = JNI_FALSE;
/* only do this if we aren't already in the middle of processing a class on this thread */
shouldRun = tryToAcquireReentrancyToken(
jvmti(agent),
NULL); /* this thread */
if ( shouldRun ) {
/* first marshall all the parameters */
classNameStringObject = (*jnienv)->NewStringUTF(jnienv,
name);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "can't create name string");
if ( !errorOutstanding ) {
classFileBufferObject = (*jnienv)->NewByteArray(jnienv,
class_data_len);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "can't create byte arrau");
}
if ( !errorOutstanding ) {
jbyte * typedBuffer = (jbyte *) class_data; /* nasty cast, dumb JNI interface, const missing */
/* The sign cast is safe. The const cast is dumb. */
(*jnienv)->SetByteArrayRegion( jnienv,
classFileBufferObject,
0,
class_data_len,
typedBuffer);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "can't set byte array region");
}
/* now call the JPL agents to do the transforming */
/* potential future optimization: may want to skip this if there are none */
if ( !errorOutstanding ) {
jplis_assert(agent->mInstrumentationImpl != NULL);
jplis_assert(agent->mTransform != NULL);
transformedBufferObject = (*jnienv)->CallObjectMethod(
jnienv,
agent->mInstrumentationImpl,
agent->mTransform,
loaderObject,
classNameStringObject,
classBeingRedefined,
protectionDomain,
classFileBufferObject,
is_retransformer);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "transform method call failed");
}
/* Finally, unmarshall the parameters (if someone touched the buffer, tell the JVM) */
if ( !errorOutstanding ) {
if ( transformedBufferObject != NULL ) {
transformedBufferSize = (*jnienv)->GetArrayLength( jnienv,
transformedBufferObject);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "can't get array length");
if ( !errorOutstanding ) {
/* allocate the response buffer with the JVMTI allocate call.
* This is what the JVMTI spec says to do for Class File Load hook responses
*/
jvmtiError allocError = (*(jvmti(agent)))->Allocate(jvmti(agent),
transformedBufferSize,
&resultBuffer);
errorOutstanding = (allocError != JVMTI_ERROR_NONE);
jplis_assert_msg(!errorOutstanding, "can't allocate result buffer");
}
if ( !errorOutstanding ) {
(*jnienv)->GetByteArrayRegion( jnienv,
transformedBufferObject,
0,
transformedBufferSize,
(jbyte *) resultBuffer);
errorOutstanding = checkForAndClearThrowable(jnienv);
jplis_assert_msg(!errorOutstanding, "can't get byte array region");
/* in this case, we will not return the buffer to the JVMTI,
* so we need to deallocate it ourselves
*/
if ( errorOutstanding ) {
deallocate( jvmti(agent),
(void*)resultBuffer);
}
}
if ( !errorOutstanding ) {
*new_class_data_len = (transformedBufferSize);
*new_class_data = resultBuffer;
}
}
}
/* release the token */
releaseReentrancyToken( jvmti(agent),
NULL); /* this thread */
}
return;
}
/*
* Misc. internal utilities.
*/
/*
* The only checked exceptions we can throw are ClassNotFoundException and
* UnmodifiableClassException. All others map to InternalError.
*/
jthrowable
redefineClassMapper( JNIEnv * jnienv,
jthrowable throwableToMap) {
jthrowable mappedThrowable = NULL;
jplis_assert(isSafeForJNICalls(jnienv));
jplis_assert(!isUnchecked(jnienv, throwableToMap));
if ( isInstanceofClassName( jnienv,
throwableToMap,
"java/lang/ClassNotFoundException") ) {
mappedThrowable = throwableToMap;
} else {
if ( isInstanceofClassName( jnienv,
throwableToMap,
"java/lang/instrument/UnmodifiableClassException")) {
mappedThrowable = throwableToMap;
} else {
jstring message = NULL;
message = getMessageFromThrowable(jnienv, throwableToMap);
mappedThrowable = createInternalError(jnienv, message);
}
}
jplis_assert(isSafeForJNICalls(jnienv));
return mappedThrowable;
}
jobjectArray
getObjectArrayFromClasses(JNIEnv* jnienv, jclass* classes, jint classCount) {
jclass classArrayClass = NULL;
jobjectArray localArray = NULL;
jint classIndex = 0;
jboolean errorOccurred = JNI_FALSE;
/* get the class array class */
classArrayClass = (*jnienv)->FindClass(jnienv, "java/lang/Class");
errorOccurred = checkForThrowable(jnienv);
if (!errorOccurred) {
jplis_assert_msg(classArrayClass != NULL, "FindClass returned null class");
/* create the array for the classes */
localArray = (*jnienv)->NewObjectArray(jnienv, classCount, classArrayClass, NULL);
errorOccurred = checkForThrowable(jnienv);
if (!errorOccurred) {
jplis_assert_msg(localArray != NULL, "NewObjectArray returned null array");
/* now copy refs to all the classes and put them into the array */
for (classIndex = 0; classIndex < classCount; classIndex++) {
/* put class into array */
(*jnienv)->SetObjectArrayElement(jnienv, localArray, classIndex, classes[classIndex]);
errorOccurred = checkForThrowable(jnienv);
if (errorOccurred) {
localArray = NULL;
break;
}
}
}
}
return localArray;
}
/* Return the environment with the retransformation capability.
* Create it if it doesn't exist.
* Return NULL if it can't be created.
*/
jvmtiEnv *
retransformableEnvironment(JPLISAgent * agent) {
jvmtiEnv * retransformerEnv = NULL;
jint jnierror = JNI_OK;
jvmtiCapabilities desiredCapabilities;
jvmtiEventCallbacks callbacks;
jvmtiError jvmtierror;
if (agent->mRetransformEnvironment.mJVMTIEnv != NULL) {
return agent->mRetransformEnvironment.mJVMTIEnv;
}
jnierror = (*agent->mJVM)->GetEnv( agent->mJVM,
(void **) &retransformerEnv,
JVMTI_VERSION_1_1);
if ( jnierror != JNI_OK ) {
return NULL;
}
jvmtierror = (*retransformerEnv)->GetCapabilities(retransformerEnv, &desiredCapabilities);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
desiredCapabilities.can_retransform_classes = 1;
if (agent->mNativeMethodPrefixAdded) {
desiredCapabilities.can_set_native_method_prefix = 1;
}
jvmtierror = (*retransformerEnv)->AddCapabilities(retransformerEnv, &desiredCapabilities);
if (jvmtierror != JVMTI_ERROR_NONE) {
/* cannot get the capability, dispose of the retransforming environment */
jvmtierror = (*retransformerEnv)->DisposeEnvironment(retransformerEnv);
jplis_assert(jvmtierror == JVMTI_ERROR_NOT_AVAILABLE);
return NULL;
}
memset(&callbacks, 0, sizeof(callbacks));
callbacks.ClassFileLoadHook = &eventHandlerClassFileLoadHook;
jvmtierror = (*retransformerEnv)->SetEventCallbacks(retransformerEnv,
&callbacks,
sizeof(callbacks));
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
if (jvmtierror == JVMTI_ERROR_NONE) {
// install the retransforming environment
agent->mRetransformEnvironment.mJVMTIEnv = retransformerEnv;
agent->mRetransformEnvironment.mIsRetransformer = JNI_TRUE;
// Make it for ClassFileLoadHook handling
jvmtierror = (*retransformerEnv)->SetEnvironmentLocalStorage(
retransformerEnv,
&(agent->mRetransformEnvironment));
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
if (jvmtierror == JVMTI_ERROR_NONE) {
return retransformerEnv;
}
}
return NULL;
}
/*
* Underpinnings for native methods
*/
jboolean
isModifiableClass(JNIEnv * jnienv, JPLISAgent * agent, jclass clazz) {
jvmtiEnv * jvmtienv = jvmti(agent);
jvmtiError jvmtierror;
jboolean is_modifiable = JNI_FALSE;
jvmtierror = (*jvmtienv)->IsModifiableClass( jvmtienv,
clazz,
&is_modifiable);
check_phase_ret_false(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
return is_modifiable;
}
jboolean
isRetransformClassesSupported(JNIEnv * jnienv, JPLISAgent * agent) {
return agent->mRetransformEnvironment.mIsRetransformer;
}
void
setHasRetransformableTransformers(JNIEnv * jnienv, JPLISAgent * agent, jboolean has) {
jvmtiEnv * retransformerEnv = retransformableEnvironment(agent);
jvmtiError jvmtierror;
jplis_assert(retransformerEnv != NULL);
jvmtierror = (*retransformerEnv)->SetEventNotificationMode(
retransformerEnv,
has? JVMTI_ENABLE : JVMTI_DISABLE,
JVMTI_EVENT_CLASS_FILE_LOAD_HOOK,
NULL /* all threads */);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
}
void
retransformClasses(JNIEnv * jnienv, JPLISAgent * agent, jobjectArray classes) {
jvmtiEnv * retransformerEnv = retransformableEnvironment(agent);
jboolean errorOccurred = JNI_FALSE;
jvmtiError errorCode = JVMTI_ERROR_NONE;
jsize numClasses = 0;
jclass * classArray = NULL;
/* This is supposed to be checked by caller, but just to be sure */
if (retransformerEnv == NULL) {
jplis_assert(retransformerEnv != NULL);
errorOccurred = JNI_TRUE;
errorCode = JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
}
/* This was supposed to be checked by caller too */
if (!errorOccurred && classes == NULL) {
jplis_assert(classes != NULL);
errorOccurred = JNI_TRUE;
errorCode = JVMTI_ERROR_NULL_POINTER;
}
if (!errorOccurred) {
numClasses = (*jnienv)->GetArrayLength(jnienv, classes);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (!errorOccurred && numClasses == 0) {
jplis_assert(numClasses != 0);
errorOccurred = JNI_TRUE;
errorCode = JVMTI_ERROR_NULL_POINTER;
}
}
if (!errorOccurred) {
classArray = (jclass *) allocate(retransformerEnv,
numClasses * sizeof(jclass));
errorOccurred = (classArray == NULL);
jplis_assert(!errorOccurred);
if (errorOccurred) {
errorCode = JVMTI_ERROR_OUT_OF_MEMORY;
}
}
if (!errorOccurred) {
jint index;
for (index = 0; index < numClasses; index++) {
classArray[index] = (*jnienv)->GetObjectArrayElement(jnienv, classes, index);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
if (classArray[index] == NULL) {
jplis_assert(classArray[index] != NULL);
errorOccurred = JNI_TRUE;
errorCode = JVMTI_ERROR_NULL_POINTER;
break;
}
}
}
if (!errorOccurred) {
errorCode = (*retransformerEnv)->RetransformClasses(retransformerEnv,
numClasses, classArray);
errorOccurred = (errorCode != JVMTI_ERROR_NONE);
}
/* Give back the buffer if we allocated it. Throw any exceptions after.
*/
if (classArray != NULL) {
deallocate(retransformerEnv, (void*)classArray);
}
if (errorCode != JVMTI_ERROR_NONE) {
createAndThrowThrowableFromJVMTIErrorCode(jnienv, errorCode);
}
mapThrownThrowableIfNecessary(jnienv, redefineClassMapper);
}
/*
* Java code must not call this with a null list or a zero-length list.
*/
void
redefineClasses(JNIEnv * jnienv, JPLISAgent * agent, jobjectArray classDefinitions) {
jvmtiEnv* jvmtienv = jvmti(agent);
jboolean errorOccurred = JNI_FALSE;
jclass classDefClass = NULL;
jmethodID getDefinitionClassMethodID = NULL;
jmethodID getDefinitionClassFileMethodID = NULL;
jvmtiClassDefinition* classDefs = NULL;
jbyteArray* targetFiles = NULL;
jsize numDefs = 0;
jplis_assert(classDefinitions != NULL);
numDefs = (*jnienv)->GetArrayLength(jnienv, classDefinitions);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (!errorOccurred) {
jplis_assert(numDefs > 0);
/* get method IDs for methods to call on class definitions */
classDefClass = (*jnienv)->FindClass(jnienv, "java/lang/instrument/ClassDefinition");
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
}
if (!errorOccurred) {
getDefinitionClassMethodID = (*jnienv)->GetMethodID( jnienv,
classDefClass,
"getDefinitionClass",
"()Ljava/lang/Class;");
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
}
if (!errorOccurred) {
getDefinitionClassFileMethodID = (*jnienv)->GetMethodID( jnienv,
classDefClass,
"getDefinitionClassFile",
"()[B");
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
}
if (!errorOccurred) {
classDefs = (jvmtiClassDefinition *) allocate(
jvmtienv,
numDefs * sizeof(jvmtiClassDefinition));
errorOccurred = (classDefs == NULL);
jplis_assert(!errorOccurred);
if ( errorOccurred ) {
createAndThrowThrowableFromJVMTIErrorCode(jnienv, JVMTI_ERROR_OUT_OF_MEMORY);
}
else {
/*
* We have to save the targetFile values that we compute so
* that we can release the class_bytes arrays that are
* returned by GetByteArrayElements(). In case of a JNI
* error, we can't (easily) recompute the targetFile values
* and we still want to free any memory we allocated.
*/
targetFiles = (jbyteArray *) allocate(jvmtienv,
numDefs * sizeof(jbyteArray));
errorOccurred = (targetFiles == NULL);
jplis_assert(!errorOccurred);
if ( errorOccurred ) {
deallocate(jvmtienv, (void*)classDefs);
createAndThrowThrowableFromJVMTIErrorCode(jnienv,
JVMTI_ERROR_OUT_OF_MEMORY);
}
else {
jint i, j;
// clear classDefs so we can correctly free memory during errors
memset(classDefs, 0, numDefs * sizeof(jvmtiClassDefinition));
for (i = 0; i < numDefs; i++) {
jclass classDef = NULL;
classDef = (*jnienv)->GetObjectArrayElement(jnienv, classDefinitions, i);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
classDefs[i].klass = (*jnienv)->CallObjectMethod(jnienv, classDef, getDefinitionClassMethodID);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
targetFiles[i] = (*jnienv)->CallObjectMethod(jnienv, classDef, getDefinitionClassFileMethodID);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
classDefs[i].class_byte_count = (*jnienv)->GetArrayLength(jnienv, targetFiles[i]);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
/*
* Allocate class_bytes last so we don't have to free
* memory on a partial row error.
*/
classDefs[i].class_bytes = (unsigned char*)(*jnienv)->GetByteArrayElements(jnienv, targetFiles[i], NULL);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
}
if (!errorOccurred) {
jvmtiError errorCode = JVMTI_ERROR_NONE;
errorCode = (*jvmtienv)->RedefineClasses(jvmtienv, numDefs, classDefs);
if (errorCode == JVMTI_ERROR_WRONG_PHASE) {
/* insulate caller from the wrong phase error */
errorCode = JVMTI_ERROR_NONE;
} else {
errorOccurred = (errorCode != JVMTI_ERROR_NONE);
if ( errorOccurred ) {
createAndThrowThrowableFromJVMTIErrorCode(jnienv, errorCode);
}
}
}
/*
* Cleanup memory that we allocated above. If we had a
* JNI error, a JVM/TI error or no errors, index 'i'
* tracks how far we got in processing the classDefs
* array. Note: ReleaseByteArrayElements() is safe to
* call with a JNI exception pending.
*/
for (j = 0; j < i; j++) {
if ((jbyte *)classDefs[j].class_bytes != NULL) {
(*jnienv)->ReleaseByteArrayElements(jnienv,
targetFiles[j], (jbyte *)classDefs[j].class_bytes,
0 /* copy back and free */);
/*
* Only check for error if we didn't already have one
* so we don't overwrite errorOccurred.
*/
if (!errorOccurred) {
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
}
}
}
deallocate(jvmtienv, (void*)targetFiles);
deallocate(jvmtienv, (void*)classDefs);
}
}
}
mapThrownThrowableIfNecessary(jnienv, redefineClassMapper);
}
/* Cheesy sharing. ClassLoader may be null. */
jobjectArray
commonGetClassList( JNIEnv * jnienv,
JPLISAgent * agent,
jobject classLoader,
ClassListFetcher fetcher) {
jvmtiEnv * jvmtienv = jvmti(agent);
jboolean errorOccurred = JNI_FALSE;
jvmtiError jvmtierror = JVMTI_ERROR_NONE;
jint classCount = 0;
jclass * classes = NULL;
jobjectArray localArray = NULL;
/* retrieve the classes from the JVMTI agent */
jvmtierror = (*fetcher)( jvmtienv,
classLoader,
&classCount,
&classes);
check_phase_ret_blob(jvmtierror, localArray);
errorOccurred = (jvmtierror != JVMTI_ERROR_NONE);
jplis_assert(!errorOccurred);
if ( errorOccurred ) {
createAndThrowThrowableFromJVMTIErrorCode(jnienv, jvmtierror);
} else {
localArray = getObjectArrayFromClasses( jnienv,
classes,
classCount);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
/* do this whether or not we saw a problem */
deallocate(jvmtienv, (void*)classes);
}
mapThrownThrowableIfNecessary(jnienv, mapAllCheckedToInternalErrorMapper);
return localArray;
}
jvmtiError
getAllLoadedClassesClassListFetcher( jvmtiEnv * jvmtienv,
jobject classLoader,
jint * classCount,
jclass ** classes) {
return (*jvmtienv)->GetLoadedClasses(jvmtienv, classCount, classes);
}
jobjectArray
getAllLoadedClasses(JNIEnv * jnienv, JPLISAgent * agent) {
return commonGetClassList( jnienv,
agent,
NULL,
getAllLoadedClassesClassListFetcher);
}
jvmtiError
getInitiatedClassesClassListFetcher( jvmtiEnv * jvmtienv,
jobject classLoader,
jint * classCount,
jclass ** classes) {
return (*jvmtienv)->GetClassLoaderClasses(jvmtienv, classLoader, classCount, classes);
}
jobjectArray
getInitiatedClasses(JNIEnv * jnienv, JPLISAgent * agent, jobject classLoader) {
return commonGetClassList( jnienv,
agent,
classLoader,
getInitiatedClassesClassListFetcher);
}
jlong
getObjectSize(JNIEnv * jnienv, JPLISAgent * agent, jobject objectToSize) {
jvmtiEnv * jvmtienv = jvmti(agent);
jlong objectSize = -1;
jvmtiError jvmtierror = JVMTI_ERROR_NONE;
jvmtierror = (*jvmtienv)->GetObjectSize(jvmtienv, objectToSize, &objectSize);
check_phase_ret_0(jvmtierror);
jplis_assert(jvmtierror == JVMTI_ERROR_NONE);
if ( jvmtierror != JVMTI_ERROR_NONE ) {
createAndThrowThrowableFromJVMTIErrorCode(jnienv, jvmtierror);
}
mapThrownThrowableIfNecessary(jnienv, mapAllCheckedToInternalErrorMapper);
return objectSize;
}
void
appendToClassLoaderSearch(JNIEnv * jnienv, JPLISAgent * agent, jstring jarFile, jboolean isBootLoader)
{
jvmtiEnv * jvmtienv = jvmti(agent);
jboolean errorOutstanding;
jvmtiError jvmtierror;
const char* utf8Chars;
jsize utf8Len;
jboolean isCopy;
char platformChars[MAXPATHLEN];
int platformLen;
utf8Len = (*jnienv)->GetStringUTFLength(jnienv, jarFile);
errorOutstanding = checkForAndClearThrowable(jnienv);
if (!errorOutstanding) {
utf8Chars = (*jnienv)->GetStringUTFChars(jnienv, jarFile, &isCopy);
errorOutstanding = checkForAndClearThrowable(jnienv);
if (!errorOutstanding && utf8Chars != NULL) {
/*
* JVMTI spec'ed to use modified UTF8. At this time this is not implemented
* the platform encoding is used.
*/
platformLen = convertUft8ToPlatformString((char*)utf8Chars, utf8Len, platformChars, MAXPATHLEN);
if (platformLen < 0) {
createAndThrowInternalError(jnienv);
return;
}
(*jnienv)->ReleaseStringUTFChars(jnienv, jarFile, utf8Chars);
errorOutstanding = checkForAndClearThrowable(jnienv);
if (!errorOutstanding) {
if (isBootLoader) {
jvmtierror = (*jvmtienv)->AddToBootstrapClassLoaderSearch(jvmtienv, platformChars);
} else {
jvmtierror = (*jvmtienv)->AddToSystemClassLoaderSearch(jvmtienv, platformChars);
}
check_phase_ret(jvmtierror);
if ( jvmtierror != JVMTI_ERROR_NONE ) {
createAndThrowThrowableFromJVMTIErrorCode(jnienv, jvmtierror);
}
}
}
}
mapThrownThrowableIfNecessary(jnienv, mapAllCheckedToInternalErrorMapper);
}
/*
* Set the prefixes used to wrap native methods (so they can be instrumented).
* Each transform can set a prefix, any that have been set come in as prefixArray.
* Convert them in native strings in a native array then call JVM TI.
* One a given call, this function handles either the prefixes for retransformable
* transforms or for normal transforms.
*/
void
setNativeMethodPrefixes(JNIEnv * jnienv, JPLISAgent * agent, jobjectArray prefixArray,
jboolean isRetransformable) {
jvmtiEnv* jvmtienv;
jvmtiError err = JVMTI_ERROR_NONE;
jsize arraySize;
jboolean errorOccurred = JNI_FALSE;
jplis_assert(prefixArray != NULL);
if (isRetransformable) {
jvmtienv = agent->mRetransformEnvironment.mJVMTIEnv;
} else {
jvmtienv = agent->mNormalEnvironment.mJVMTIEnv;
}
arraySize = (*jnienv)->GetArrayLength(jnienv, prefixArray);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (!errorOccurred) {
/* allocate the native to hold the native prefixes */
const char** prefixes = (const char**) allocate(jvmtienv,
arraySize * sizeof(char*));
/* since JNI ReleaseStringUTFChars needs the jstring from which the native
* string was allocated, we store them in a parallel array */
jstring* originForRelease = (jstring*) allocate(jvmtienv,
arraySize * sizeof(jstring));
errorOccurred = (prefixes == NULL || originForRelease == NULL);
jplis_assert(!errorOccurred);
if ( errorOccurred ) {
createAndThrowThrowableFromJVMTIErrorCode(jnienv, JVMTI_ERROR_OUT_OF_MEMORY);
}
else {
jint inx = 0;
jint i;
for (i = 0; i < arraySize; i++) {
jstring prefixStr = NULL;
const char* prefix;
jsize prefixLen;
jboolean isCopy;
prefixStr = (jstring) ((*jnienv)->GetObjectArrayElement(jnienv,
prefixArray, i));
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
if (prefixStr == NULL) {
continue;
}
prefixLen = (*jnienv)->GetStringUTFLength(jnienv, prefixStr);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (errorOccurred) {
break;
}
if (prefixLen > 0) {
prefix = (*jnienv)->GetStringUTFChars(jnienv, prefixStr, &isCopy);
errorOccurred = checkForThrowable(jnienv);
jplis_assert(!errorOccurred);
if (!errorOccurred && prefix != NULL) {
prefixes[inx] = prefix;
originForRelease[inx] = prefixStr;
++inx;
}
}
}
err = (*jvmtienv)->SetNativeMethodPrefixes(jvmtienv, inx, (char**)prefixes);
/* can be called from any phase */
jplis_assert(err == JVMTI_ERROR_NONE);
for (i = 0; i < inx; i++) {
(*jnienv)->ReleaseStringUTFChars(jnienv, originForRelease[i], prefixes[i]);
}
}
deallocate(jvmtienv, (void*)prefixes);
deallocate(jvmtienv, (void*)originForRelease);
}
}
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