/*

 * Copyright (c) 2003, 2019, 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.

 *

 */

#ifndef SHARE_PRIMS_JVMTIENVBASE_HPP

#define SHARE_PRIMS_JVMTIENVBASE_HPP

#include "classfile/classLoader.hpp"

#include "prims/jvmtiEnvThreadState.hpp"

#include "prims/jvmtiEventController.hpp"

#include "prims/jvmtiThreadState.hpp"

#include "oops/oopHandle.hpp"

#include "runtime/fieldDescriptor.hpp"

#include "runtime/frame.hpp"

#include "runtime/orderAccess.hpp"

#include "runtime/thread.hpp"

#include "runtime/vmOperations.hpp"

#include "utilities/growableArray.hpp"

#include "utilities/macros.hpp"

//

// Forward Declarations

//

class JvmtiEnv;

class JvmtiThreadState;

class JvmtiRawMonitor; // for jvmtiEnv.hpp

class JvmtiEventControllerPrivate;

class JvmtiTagMap;

// One JvmtiEnv object is created per jvmti attachment;

// done via JNI GetEnv() call. Multiple attachments are

// allowed in jvmti.

class JvmtiEnvBase : public CHeapObj<mtInternal> {

 private:

#if INCLUDE_JVMTI

  static JvmtiEnvBase*     _head_environment;  // head of environment list

#endif // INCLUDE_JVMTI

  static bool              _globally_initialized;

  static jvmtiPhase        _phase;

  static volatile int      _dying_thread_env_iteration_count;

 public:

  enum {

    JDK15_JVMTI_VERSION = JVMTI_VERSION_1_0 +  33,  /* version: 1.0.33  */

    JDK16_JVMTI_VERSION = JVMTI_VERSION_1_1 + 102,  /* version: 1.1.102 */

    JDK17_JVMTI_VERSION = JVMTI_VERSION_1_2 +   2   /* version: 1.2.2   */

  };

  static jvmtiPhase  get_phase()                    { return _phase; }

  static jvmtiPhase  get_phase(jvmtiEnv* env)       { return ((JvmtiEnvBase*)JvmtiEnv_from_jvmti_env(env))->phase(); }

  static void  set_phase(jvmtiPhase phase)          { _phase = phase; }

  static bool is_vm_live()                          { return _phase == JVMTI_PHASE_LIVE; }

  static void entering_dying_thread_env_iteration() { ++_dying_thread_env_iteration_count; }

  static void leaving_dying_thread_env_iteration()  { --_dying_thread_env_iteration_count; }

  static bool is_inside_dying_thread_env_iteration(){ return _dying_thread_env_iteration_count > 0; }

 private:

  enum {

      JVMTI_MAGIC    = 0x71EE,

      DISPOSED_MAGIC = 0xDEFC,

      BAD_MAGIC      = 0xDEAD

  };

  jvmtiEnv _jvmti_external;

  jint _magic;

  jint _version;  // version value passed to JNI GetEnv()

  JvmtiEnvBase* _next;

  bool _is_retransformable;

  const void *_env_local_storage;     // per env agent allocated data.

  jvmtiEventCallbacks _event_callbacks;

  jvmtiExtEventCallbacks _ext_event_callbacks;

  JvmtiTagMap* volatile _tag_map;

  JvmtiEnvEventEnable _env_event_enable;

  jvmtiCapabilities _current_capabilities;

  jvmtiCapabilities _prohibited_capabilities;

  volatile bool _class_file_load_hook_ever_enabled;

  static volatile bool _needs_clean_up;

  char** _native_method_prefixes;

  int    _native_method_prefix_count;

 protected:

  JvmtiEnvBase(jint version);

  ~JvmtiEnvBase();

  void dispose();

  void env_dispose();

  void set_env_local_storage(const void* data)     { _env_local_storage = data; }

  const void* get_env_local_storage()              { return _env_local_storage; }

  void record_class_file_load_hook_enabled();

  void record_first_time_class_file_load_hook_enabled();

  char** get_native_method_prefixes()              { return _native_method_prefixes; }

  int    get_native_method_prefix_count()          { return _native_method_prefix_count; }

  jvmtiError set_native_method_prefixes(jint prefix_count, char** prefixes);

 private:

  friend class JvmtiEventControllerPrivate;

  void initialize();

  void set_event_callbacks(const jvmtiEventCallbacks* callbacks, jint size_of_callbacks);

  static void globally_initialize();

  static void periodic_clean_up();

  friend class JvmtiEnvIterator;

  JvmtiEnv* next_environment()                     { return (JvmtiEnv*)_next; }

  void set_next_environment(JvmtiEnvBase* env)     { _next = env; }

  static JvmtiEnv* head_environment()              {

    JVMTI_ONLY(return (JvmtiEnv*)_head_environment);

    NOT_JVMTI(return NULL);

  }

 public:

  jvmtiPhase  phase();

  bool is_valid();

  bool use_version_1_0_semantics();  // agent asked for version 1.0

  bool use_version_1_1_semantics();  // agent asked for version 1.1

  bool use_version_1_2_semantics();  // agent asked for version 1.2

  bool is_retransformable()                        { return _is_retransformable; }

  static ByteSize jvmti_external_offset() {

    return byte_offset_of(JvmtiEnvBase, _jvmti_external);

  };

  static JvmtiEnv* JvmtiEnv_from_jvmti_env(jvmtiEnv *env) {

    return (JvmtiEnv*)((intptr_t)env - in_bytes(jvmti_external_offset()));

  };

  jvmtiCapabilities *get_capabilities()             { return &_current_capabilities; }

  jvmtiCapabilities *get_prohibited_capabilities()  { return &_prohibited_capabilities; }

  bool early_class_hook_env() {

    return get_capabilities()->can_generate_early_class_hook_events != 0

        && get_capabilities()->can_generate_all_class_hook_events != 0;

  }

  bool early_vmstart_env() {

    return get_capabilities()->can_generate_early_vmstart != 0;

  }

  static char** get_all_native_method_prefixes(int* count_ptr);

  // This test will answer true when all environments have been disposed and some have

  // not yet been deallocated.  As a result, this test should only be used as an

  // optimization for the no environment case.

  static bool environments_might_exist() {

    return head_environment() != NULL;

  }

  static void check_for_periodic_clean_up();

  JvmtiEnvEventEnable *env_event_enable() {

    return &_env_event_enable;

  }

  jvmtiError allocate(jlong size, unsigned char** mem_ptr) {

    if (size < 0) {

      return JVMTI_ERROR_ILLEGAL_ARGUMENT;

    }

    if (size == 0) {

      *mem_ptr = NULL;

    } else {

      *mem_ptr = (unsigned char *)os::malloc((size_t)size, mtInternal);

      if (*mem_ptr == NULL) {

        return JVMTI_ERROR_OUT_OF_MEMORY;

      }

    }

    return JVMTI_ERROR_NONE;

  }

  jvmtiError deallocate(unsigned char* mem) {

    if (mem != NULL) {

      os::free(mem);

    }

    return JVMTI_ERROR_NONE;

  }

  // Memory functions

  unsigned char* jvmtiMalloc(jlong size);  // don't use this - call allocate

  // method to create a local handle

  jobject jni_reference(Handle hndl);

  // method to create a local handle.

  // This function allows caller to specify which

  // threads local handle table to use.

  jobject jni_reference(JavaThread *thread, Handle hndl);

  // method to destroy a local handle

  void destroy_jni_reference(jobject jobj);

  // method to destroy a local handle.

  // This function allows caller to specify which

  // threads local handle table to use.

  void destroy_jni_reference(JavaThread *thread, jobject jobj);

  jvmtiEnv* jvmti_external() { return &_jvmti_external; };

// Event Dispatch

  bool has_callback(jvmtiEvent event_type) {

    assert(event_type >= JVMTI_MIN_EVENT_TYPE_VAL &&

           event_type <= JVMTI_MAX_EVENT_TYPE_VAL, "checking");

    return ((void**)&_event_callbacks)[event_type-JVMTI_MIN_EVENT_TYPE_VAL] != NULL;

  }

  jvmtiEventCallbacks* callbacks() {

    return &_event_callbacks;

  }

  jvmtiExtEventCallbacks* ext_callbacks() {

    return &_ext_event_callbacks;

  }

  void set_tag_map(JvmtiTagMap* tag_map) {

    _tag_map = tag_map;

  }

  JvmtiTagMap* tag_map() {

    return _tag_map;

  }

  JvmtiTagMap* tag_map_acquire() {

  }

  void release_set_tag_map(JvmtiTagMap* tag_map) {

  }

  // return true if event is enabled globally or for any thread

  // True only if there is a callback for it.

  bool is_enabled(jvmtiEvent event_type) {

    return _env_event_enable.is_enabled(event_type);

  }

// Random Utilities

 protected:

  // helper methods for creating arrays of global JNI Handles from local Handles

  // allocated into environment specific storage

  jobject * new_jobjectArray(int length, Handle *handles);

  jthread * new_jthreadArray(int length, Handle *handles);

  jthreadGroup * new_jthreadGroupArray(int length, Handle *handles);

  // convert to a jni jclass from a non-null Klass*

  jclass get_jni_class_non_null(Klass* k);

  jint count_locked_objects(JavaThread *java_thread, Handle hobj);

  jvmtiError get_locked_objects_in_frame(JavaThread *calling_thread,

                                   JavaThread* java_thread,

                                   javaVFrame *jvf,

                                   GrowableArray<jvmtiMonitorStackDepthInfo*>* owned_monitors_list,

                                   jint depth);

  vframe* vframeFor(JavaThread* java_thread, jint depth);

 public:

  // get a field descriptor for the specified class and field

  static bool get_field_descriptor(Klass* k, jfieldID field, fieldDescriptor* fd);

  // JVMTI API helper functions which are called at safepoint or thread is suspended.

  jvmtiError get_frame_count(JvmtiThreadState *state, jint *count_ptr);

  jvmtiError get_frame_location(JavaThread* java_thread, jint depth,

                                              jmethodID* method_ptr, jlocation* location_ptr);

  jvmtiError get_object_monitor_usage(JavaThread *calling_thread,

                                                    jobject object, jvmtiMonitorUsage* info_ptr);

  jvmtiError get_stack_trace(JavaThread *java_thread,

                                           jint stack_depth, jint max_count,

                                           jvmtiFrameInfo* frame_buffer, jint* count_ptr);

  jvmtiError get_current_contended_monitor(JavaThread *calling_thread,

                                                         JavaThread *java_thread,

                                                         jobject *monitor_ptr);

  jvmtiError get_owned_monitors(JavaThread *calling_thread, JavaThread* java_thread,

                          GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list);

  jvmtiError check_top_frame(JavaThread* current_thread, JavaThread* java_thread,

                             jvalue value, TosState tos, Handle* ret_ob_h);

  jvmtiError force_early_return(JavaThread* java_thread, jvalue value, TosState tos);

};

// This class is the only safe means of iterating through environments.

// Note that this iteratation includes invalid environments pending

// deallocation -- in fact, some uses depend on this behavior.

class JvmtiEnvIterator : public StackObj {

 private:

  bool _entry_was_marked;

 public:

  JvmtiEnvIterator() {

    if (Threads::number_of_threads() == 0) {

      _entry_was_marked = false; // we are single-threaded, no need

    } else {

      Thread::current()->entering_jvmti_env_iteration();

      _entry_was_marked = true;

    }

  }

  ~JvmtiEnvIterator() {

    if (_entry_was_marked) {

      Thread::current()->leaving_jvmti_env_iteration();

    }

  }

  JvmtiEnv* first()                 { return JvmtiEnvBase::head_environment(); }

  JvmtiEnv* next(JvmtiEnvBase* env) { return env->next_environment(); }

};

// VM operation to update for pop top frame.

class VM_UpdateForPopTopFrame : public VM_Operation {

private:

  JvmtiThreadState* _state;

  jvmtiError _result;

public:

  VM_UpdateForPopTopFrame(JvmtiThreadState* state) {

    _state = state;

    _result = JVMTI_ERROR_NONE;

  }

  VMOp_Type type() const { return VMOp_UpdateForPopTopFrame; }

  jvmtiError result() { return _result; }

  void doit();

};

// VM operation to set frame pop.

class VM_SetFramePop : public VM_Operation {

private:

  JvmtiEnv *_env;

  JvmtiThreadState* _state;

  jint _depth;

  jvmtiError _result;

public:

  VM_SetFramePop(JvmtiEnv *env, JvmtiThreadState* state, jint depth) {

    _env = env;

    _state = state;

    _depth = depth;

    _result = JVMTI_ERROR_NONE;

  }

  // Nested operation must be allowed for the VM_EnterInterpOnlyMode that is

  // called from the JvmtiEventControllerPrivate::recompute_thread_enabled.

  bool allow_nested_vm_operations() const { return true; }

  VMOp_Type type() const { return VMOp_SetFramePop; }

  jvmtiError result() { return _result; }

  void doit();

};

// VM operation to get monitor information with stack depth.

class VM_GetOwnedMonitorInfo : public VM_Operation {

private:

  JvmtiEnv *_env;

  JavaThread* _calling_thread;

  JavaThread *_java_thread;

  jvmtiError _result;

  GrowableArray<jvmtiMonitorStackDepthInfo*> *_owned_monitors_list;

public:

  VM_GetOwnedMonitorInfo(JvmtiEnv* env, JavaThread* calling_thread,

                                   JavaThread* java_thread,

                                   GrowableArray<jvmtiMonitorStackDepthInfo*>* owned_monitor_list) {

    _env = env;

    _calling_thread = calling_thread;

    _java_thread = java_thread;

    _owned_monitors_list = owned_monitor_list;

    _result = JVMTI_ERROR_NONE;

  }

  VMOp_Type type() const { return VMOp_GetOwnedMonitorInfo; }

  void doit();

  jvmtiError result() { return _result; }

};

// VM operation to get object monitor usage.

class VM_GetObjectMonitorUsage : public VM_Operation {

private:

  JvmtiEnv *_env;

  jobject _object;

  JavaThread* _calling_thread;

  jvmtiMonitorUsage* _info_ptr;

  jvmtiError _result;

public:

  VM_GetObjectMonitorUsage(JvmtiEnv *env, JavaThread* calling_thread, jobject object, jvmtiMonitorUsage* info_ptr) {

    _env = env;

    _object = object;

    _calling_thread = calling_thread;

    _info_ptr = info_ptr;

  }

  VMOp_Type type() const { return VMOp_GetObjectMonitorUsage; }

  jvmtiError result() { return _result; }

  void doit() {

    _result = ((JvmtiEnvBase*) _env)->get_object_monitor_usage(_calling_thread, _object, _info_ptr);

  }

};

// VM operation to get current contended monitor.

class VM_GetCurrentContendedMonitor : public VM_Operation {

private:

  JvmtiEnv *_env;

  JavaThread *_calling_thread;

  JavaThread *_java_thread;

  jobject *_owned_monitor_ptr;

  jvmtiError _result;

public:

  VM_GetCurrentContendedMonitor(JvmtiEnv *env, JavaThread *calling_thread, JavaThread *java_thread, jobject *mon_ptr) {

    _env = env;

    _calling_thread = calling_thread;

    _java_thread = java_thread;

    _owned_monitor_ptr = mon_ptr;

  }

  VMOp_Type type() const { return VMOp_GetCurrentContendedMonitor; }

  jvmtiError result() { return _result; }

  void doit();

};

// VM operation to get stack trace at safepoint.

class VM_GetStackTrace : public VM_Operation {

private:

  JvmtiEnv *_env;

  JavaThread *_java_thread;

  jint _start_depth;

  jint _max_count;

  jvmtiFrameInfo *_frame_buffer;

  jint *_count_ptr;

  jvmtiError _result;

public:

  VM_GetStackTrace(JvmtiEnv *env, JavaThread *java_thread,

                   jint start_depth, jint max_count,

                   jvmtiFrameInfo* frame_buffer, jint* count_ptr) {

    _env = env;

    _java_thread = java_thread;

    _start_depth = start_depth;

    _max_count = max_count;

    _frame_buffer = frame_buffer;

    _count_ptr = count_ptr;

  }

  jvmtiError result() { return _result; }

  VMOp_Type type() const { return VMOp_GetStackTrace; }

  void doit();

};

// forward declaration

struct StackInfoNode;

// VM operation to get stack trace at safepoint.

class VM_GetMultipleStackTraces : public VM_Operation {

private:

  JvmtiEnv *_env;

  jint _max_frame_count;

  jvmtiStackInfo *_stack_info;

  jvmtiError _result;

  int _frame_count_total;

  struct StackInfoNode *_head;

  JvmtiEnvBase *env()                 { return (JvmtiEnvBase *)_env; }

  jint max_frame_count()              { return _max_frame_count; }

  struct StackInfoNode *head()        { return _head; }

  void set_head(StackInfoNode *head)  { _head = head; }

protected:

  void set_result(jvmtiError result)  { _result = result; }

  void fill_frames(jthread jt, JavaThread *thr, oop thread_oop);

  void allocate_and_fill_stacks(jint thread_count);

public:

  VM_GetMultipleStackTraces(JvmtiEnv *env, jint max_frame_count) {

    _env = env;

    _max_frame_count = max_frame_count;

    _frame_count_total = 0;

    _head = NULL;

    _result = JVMTI_ERROR_NONE;

  }

  VMOp_Type type() const             { return VMOp_GetMultipleStackTraces; }

  jvmtiStackInfo *stack_info()       { return _stack_info; }

  jvmtiError result()                { return _result; }

};

// VM operation to get stack trace at safepoint.

class VM_GetAllStackTraces : public VM_GetMultipleStackTraces {

private:

  JavaThread *_calling_thread;