/*

 * Copyright (c) 2003, 2017, 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.

 */

#ifndef _JPLISAGENT_H_

#define _JPLISAGENT_H_

#include    <jni.h>

#include    <jvmti.h>

#ifdef __cplusplus

extern "C" {

#endif

/*

 *  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.

 */

/*

 *  Forward definitions

 */

struct  _JPLISAgent;

typedef struct _JPLISAgent        JPLISAgent;

typedef struct _JPLISEnvironment  JPLISEnvironment;

/* constants for class names and methods names and such

    these all must stay in sync with Java code & interfaces

*/

#define JPLIS_INSTRUMENTIMPL_CLASSNAME                      "sun/instrument/InstrumentationImpl"

#define JPLIS_INSTRUMENTIMPL_CONSTRUCTOR_METHODNAME         "<init>"

#define JPLIS_INSTRUMENTIMPL_CONSTRUCTOR_METHODSIGNATURE    "(JZZ)V"

#define JPLIS_INSTRUMENTIMPL_PREMAININVOKER_METHODNAME      "loadClassAndCallPremain"

#define JPLIS_INSTRUMENTIMPL_PREMAININVOKER_METHODSIGNATURE "(Ljava/lang/String;Ljava/lang/String;)V"

#define JPLIS_INSTRUMENTIMPL_AGENTMAININVOKER_METHODNAME      "loadClassAndCallAgentmain"

#define JPLIS_INSTRUMENTIMPL_AGENTMAININVOKER_METHODSIGNATURE "(Ljava/lang/String;Ljava/lang/String;)V"

#define JPLIS_INSTRUMENTIMPL_TRANSFORM_METHODNAME           "transform"

#define JPLIS_INSTRUMENTIMPL_TRANSFORM_METHODSIGNATURE      \

    "(Ljava/lang/Module;Ljava/lang/ClassLoader;Ljava/lang/String;Ljava/lang/Class;Ljava/security/ProtectionDomain;[BZ)[B"

/*

 *  Error messages

 */

#define JPLIS_ERRORMESSAGE_CANNOTSTART              "processing of -javaagent failed"

/*

 *  Our initialization errors

 */

typedef enum {

  JPLIS_INIT_ERROR_NONE,

  JPLIS_INIT_ERROR_CANNOT_CREATE_NATIVE_AGENT,

  JPLIS_INIT_ERROR_FAILURE,

  JPLIS_INIT_ERROR_ALLOCATION_FAILURE,

  JPLIS_INIT_ERROR_AGENT_CLASS_NOT_SPECIFIED

} JPLISInitializationError;

struct _JPLISEnvironment {

    jvmtiEnv *              mJVMTIEnv;              /* the JVM TI environment */

    JPLISAgent *            mAgent;                 /* corresponding agent */

    jboolean                mIsRetransformer;       /* indicates if special environment */

};

struct _JPLISAgent {

    JavaVM *                mJVM;                   /* handle to the JVM */

    JPLISEnvironment        mNormalEnvironment;     /* for every thing but retransform stuff */

    JPLISEnvironment        mRetransformEnvironment;/* for retransform stuff only */

    jobject                 mInstrumentationImpl;   /* handle to the Instrumentation instance */

    jmethodID               mPremainCaller;         /* method on the InstrumentationImpl that does the premain stuff (cached to save lots of lookups) */

    jmethodID               mAgentmainCaller;       /* method on the InstrumentationImpl for agents loaded via attach mechanism */

    jmethodID               mTransform;             /* method on the InstrumentationImpl that does the class file transform */

    jboolean                mRedefineAvailable;     /* cached answer to "does this agent support redefine" */

    jboolean                mRedefineAdded;         /* indicates if can_redefine_classes capability has been added */

    jboolean                mNativeMethodPrefixAvailable; /* cached answer to "does this agent support prefixing" */

    jboolean                mNativeMethodPrefixAdded;     /* indicates if can_set_native_method_prefix capability has been added */

    char const *            mAgentClassName;        /* agent class name */

    char const *            mOptionsString;         /* -javaagent options string */

    const char *            mJarfile;               /* agent jar file name */

};

/*

 * JVMTI event handlers

 */

/* VMInit event handler. Installed during OnLoad, then removed during VMInit. */

extern void JNICALL

eventHandlerVMInit( jvmtiEnv *      jvmtienv,

                    JNIEnv *        jnienv,

                    jthread         thread);

/*

 * ClassFileLoadHook event handler.

 * Enabled when the first transformer is added;

 * Disabled when the last transformer is removed.

 */

extern void JNICALL

eventHandlerClassFileLoadHook(  jvmtiEnv *              jvmtienv,

                                JNIEnv *                jnienv,

                                jclass                  class_being_redefined,

                                jobject                 loader,

                                const char*             name,

                                jobject                 protectionDomain,

                                jint                    class_data_len,

                                const unsigned char*    class_data,

                                jint*                   new_class_data_len,

                                unsigned char**         new_class_data);

/*

 * Main entry points for the JPLIS JVMTI agent code

 */

/* looks up the  environment instance. returns null if there isn't one */

extern JPLISEnvironment *

getJPLISEnvironment(jvmtiEnv * jvmtienv);

/*  Creates a new JPLIS agent.

 *  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.

 */

extern JPLISInitializationError

createNewJPLISAgent(JavaVM * vm, JPLISAgent **agent_ptr);

/* Adds can_redefine_classes capability */

extern void

addRedefineClassesCapability(JPLISAgent * agent);

/* Add the can_set_native_method_prefix capability */

extern void

addNativeMethodPrefixCapability(JPLISAgent * agent);

/* Add the can_maintain_original_method_order capability (for testing) */

extern void

addOriginalMethodOrderCapability(JPLISAgent * agent);

/* Our JPLIS agent is paralleled by a Java InstrumentationImpl instance.

 * This routine uses JNI to create and initialized the Java instance.

 * Returns true if it succeeds, false otherwise.

 */

extern jboolean

createInstrumentationImpl( JNIEnv *        jnienv,

                           JPLISAgent *    agent);

/* during OnLoad phase (command line parsing)

 *  record the parameters of -javaagent

 */

extern JPLISInitializationError

recordCommandLineData(  JPLISAgent *    agent,

                        const char *    agentClass,

                        const char *    optionsString );

/* Swaps the start phase event handlers out and the live phase event handlers in.

 * Also used in attach to enabled live phase event handlers.

 * Returns true if it succeeds, false otherwise.

 */

extern jboolean

setLivePhaseEventHandlers(  JPLISAgent * agent);

/* Loads the Java agent according to the already processed command line. For each,

 * loads the Java agent class, then calls the premain method.

 * Returns true if all Java agent classes are loaded and all premain methods complete with no exceptions,

 * false otherwise.

 */

extern jboolean

startJavaAgent( JPLISAgent *    agent,

                JNIEnv *        jnienv,

                const char *    classname,

                const char *    optionsString,

                jmethodID       agentMainMethod);

/* during VMInit processing

 *  this is how the invocation engine (callback wrapper) tells us to start up all the javaagents

 */

extern jboolean

processJavaStart(   JPLISAgent *    agent,

                    JNIEnv *        jnienv);

/* on an ongoing basis,

 *  this is how the invocation engine (callback wrapper) tells us to process a class file

 */

extern void

transformClassFile(             JPLISAgent *            agent,

                                JNIEnv *                jnienv,

                                jobject                 loader,

                                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);

/* on an ongoing basis,

 *  Return the environment with the retransformation capability.

 *  Create it if it doesn't exist.

 */

extern jvmtiEnv *

retransformableEnvironment(JPLISAgent * agent);

/* on an ongoing basis,

 *  these are implementations of the Instrumentation services.

 *  Most are simple covers for JVMTI access services. These are the guts of the InstrumentationImpl

 *  native methods.

 */

extern jboolean

isModifiableClass(JNIEnv * jnienv, JPLISAgent * agent, jclass clazz);

extern jboolean

isRetransformClassesSupported(JNIEnv * jnienv, JPLISAgent * agent);

extern void

setHasTransformers(JNIEnv * jnienv, JPLISAgent * agent, jboolean has);

extern void

setHasRetransformableTransformers(JNIEnv * jnienv, JPLISAgent * agent, jboolean has);

extern void

retransformClasses(JNIEnv * jnienv, JPLISAgent * agent, jobjectArray classes);

extern void

redefineClasses(JNIEnv * jnienv, JPLISAgent * agent, jobjectArray classDefinitions);

extern jobjectArray

getAllLoadedClasses(JNIEnv * jnienv, JPLISAgent * agent);

extern jobjectArray

getInitiatedClasses(JNIEnv * jnienv, JPLISAgent * agent, jobject classLoader);

extern jlong

getObjectSize(JNIEnv * jnienv, JPLISAgent * agent, jobject objectToSize);

extern void

appendToClassLoaderSearch(JNIEnv * jnienv, JPLISAgent * agent, jstring jarFile, jboolean isBootLoader);

extern void

setNativeMethodPrefixes(JNIEnv * jnienv, JPLISAgent * agent, jobjectArray prefixArray,

                        jboolean isRetransformable);

#define jvmti(a) a->mNormalEnvironment.mJVMTIEnv

/*

 * A set of macros for insulating the JLI method callers from

 * JVMTI_ERROR_WRONG_PHASE return codes.

 */

/* for a JLI method where "blob" is executed before simply returning */

#define check_phase_blob_ret(ret, blob)      \

    if ((ret) == JVMTI_ERROR_WRONG_PHASE) {  \

        blob;                                \

        return;                              \

    }

/* for a JLI method where simply returning is benign */

#define check_phase_ret(ret)                 \

    if ((ret) == JVMTI_ERROR_WRONG_PHASE) {  \

        return;                              \

    }

/* for a JLI method where returning zero (0) is benign */

#define check_phase_ret_0(ret)               \

    if ((ret) == JVMTI_ERROR_WRONG_PHASE) {  \

        return 0;                            \

    }

/* for a JLI method where returning one (1) is benign */

#define check_phase_ret_1(ret)               \

    if ((ret) == JVMTI_ERROR_WRONG_PHASE) {  \

        return 1;                            \

    }

/* for a case where a specific "blob" must be returned */

#define check_phase_ret_blob(ret, blob)      \

    if ((ret) == JVMTI_ERROR_WRONG_PHASE) {  \

        return (blob);                       \

    }

/* for a JLI method where returning false is benign */

#define check_phase_ret_false(ret)           \

    if ((ret) == JVMTI_ERROR_WRONG_PHASE) {  \

        return (jboolean) 0;                 \

    }

#ifdef __cplusplus

} /* extern "C" */

#endif /* __cplusplus */

#endif