/*

 * Copyright (c) 1998, 2010, 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.

 *

 */

// Forward declarations

class JvmtiEventControllerPrivate;

class JvmtiManageCapabilities;

class JvmtiEnv;

class JvmtiThreadState;

class AttachOperation;

#ifndef JVMTI_KERNEL

#define JVMTI_SUPPORT_FLAG(key)                                         \

  private:                                                              \

  static bool  _##key;                                                  \

  public:                                                               \

  inline static void set_##key(bool on)       { _##key = (on != 0); }   \

  inline static bool key()                    { return _##key; }

#else  // JVMTI_KERNEL

#define JVMTI_SUPPORT_FLAG(key)                                           \

  private:                                                                \

  const static bool _##key = false;                                       \

  public:                                                                 \

  inline static void set_##key(bool on)       { report_unsupported(on); } \

  inline static bool key()                    { return _##key; }

#endif // JVMTI_KERNEL

// This class contains the JVMTI interface for the rest of hotspot.

//

class JvmtiExport : public AllStatic {

 private:

  static int         _field_access_count;

  static int         _field_modification_count;

  static bool        _can_access_local_variables;

  static bool        _can_hotswap_or_post_breakpoint;

  static bool        _can_modify_any_class;

  static bool        _can_walk_any_space;

  JVMTI_SUPPORT_FLAG(can_get_source_debug_extension)

  JVMTI_SUPPORT_FLAG(can_maintain_original_method_order)

  JVMTI_SUPPORT_FLAG(can_post_interpreter_events)

  JVMTI_SUPPORT_FLAG(can_post_on_exceptions)

  JVMTI_SUPPORT_FLAG(can_post_breakpoint)

  JVMTI_SUPPORT_FLAG(can_post_field_access)

  JVMTI_SUPPORT_FLAG(can_post_field_modification)

  JVMTI_SUPPORT_FLAG(can_post_method_entry)

  JVMTI_SUPPORT_FLAG(can_post_method_exit)

  JVMTI_SUPPORT_FLAG(can_pop_frame)

  JVMTI_SUPPORT_FLAG(can_force_early_return)

  friend class JvmtiEventControllerPrivate;  // should only modify these flags

  JVMTI_SUPPORT_FLAG(should_post_single_step)

  JVMTI_SUPPORT_FLAG(should_post_field_access)

  JVMTI_SUPPORT_FLAG(should_post_field_modification)

  JVMTI_SUPPORT_FLAG(should_post_class_load)

  JVMTI_SUPPORT_FLAG(should_post_class_prepare)

  JVMTI_SUPPORT_FLAG(should_post_class_unload)

  JVMTI_SUPPORT_FLAG(should_post_native_method_bind)

  JVMTI_SUPPORT_FLAG(should_post_compiled_method_load)

  JVMTI_SUPPORT_FLAG(should_post_compiled_method_unload)

  JVMTI_SUPPORT_FLAG(should_post_dynamic_code_generated)

  JVMTI_SUPPORT_FLAG(should_post_monitor_contended_enter)

  JVMTI_SUPPORT_FLAG(should_post_monitor_contended_entered)

  JVMTI_SUPPORT_FLAG(should_post_monitor_wait)

  JVMTI_SUPPORT_FLAG(should_post_monitor_waited)

  JVMTI_SUPPORT_FLAG(should_post_data_dump)

  JVMTI_SUPPORT_FLAG(should_post_garbage_collection_start)

  JVMTI_SUPPORT_FLAG(should_post_garbage_collection_finish)

  JVMTI_SUPPORT_FLAG(should_post_on_exceptions)

  // ------ the below maybe don't have to be (but are for now)

  // fixed conditions here ------------

  // any events can be enabled

  JVMTI_SUPPORT_FLAG(should_post_thread_life)

  JVMTI_SUPPORT_FLAG(should_post_object_free)

  JVMTI_SUPPORT_FLAG(should_post_resource_exhausted)

  // we are holding objects on the heap - need to talk to GC - e.g.

  // breakpoint info

  JVMTI_SUPPORT_FLAG(should_clean_up_heap_objects)

  JVMTI_SUPPORT_FLAG(should_post_vm_object_alloc)

  // If flag cannot be implemented, give an error if on=true

  static void report_unsupported(bool on);

  // these should only be called by the friend class

  friend class JvmtiManageCapabilities;

  inline static void set_can_modify_any_class(bool on)                 { _can_modify_any_class = (on != 0); }

  inline static void set_can_access_local_variables(bool on)           { _can_access_local_variables = (on != 0); }

  inline static void set_can_hotswap_or_post_breakpoint(bool on)       { _can_hotswap_or_post_breakpoint = (on != 0); }

  inline static void set_can_walk_any_space(bool on)                   { _can_walk_any_space = (on != 0); }

  enum {

    JVMTI_VERSION_MASK   = 0x70000000,

    JVMTI_VERSION_VALUE  = 0x30000000,

    JVMDI_VERSION_VALUE  = 0x20000000

  };

  static void post_field_modification(JavaThread *thread, methodOop method, address location,

                                      KlassHandle field_klass, Handle object, jfieldID field,

                                      char sig_type, jvalue *value);

 private:

  // CompiledMethodUnload events are reported from the VM thread so they

  // are collected in lists (of jmethodID/addresses) and the events are posted later

  // from threads posting CompieldMethodLoad or DynamicCodeGenerated events.

  static bool _have_pending_compiled_method_unload_events;

  static GrowableArray<jmethodID>* _pending_compiled_method_unload_method_ids;

  static GrowableArray<const void *>* _pending_compiled_method_unload_code_begins;

  static JavaThread* _current_poster;

  // tests if there are CompiledMethodUnload events pending

  inline static bool have_pending_compiled_method_unload_events() {

    return _have_pending_compiled_method_unload_events;

  }

  // posts any pending CompiledMethodUnload events.

  static void post_pending_compiled_method_unload_events();

  // Perform the actual notification to interested JvmtiEnvs.

  static void post_compiled_method_unload_internal(JavaThread* self, jmethodID mid, const void* code_begin);

  // posts a DynamicCodeGenerated event (internal/private implementation).

  // The public post_dynamic_code_generated* functions make use of the

  // internal implementation.

  static void post_dynamic_code_generated_internal(const char *name, const void *code_begin, const void *code_end) KERNEL_RETURN;

  // GenerateEvents support to allow posting of CompiledMethodLoad and

  // DynamicCodeGenerated events for a given environment.

  friend class JvmtiCodeBlobEvents;

  static void post_compiled_method_load(JvmtiEnv* env, const jmethodID method, const jint length,

                                        const void *code_begin, const jint map_length,

                                        const jvmtiAddrLocationMap* map) KERNEL_RETURN;

  static void post_dynamic_code_generated(JvmtiEnv* env, const char *name, const void *code_begin,

                                          const void *code_end) KERNEL_RETURN;

  // The RedefineClasses() API breaks some invariants in the "regular"

  // system. For example, there are sanity checks when GC'ing nmethods

  // that require the containing class to be unloading. However, when a

  // method is redefined, the old method and nmethod can become GC'able

  // without the containing class unloading. The state of becoming

  // GC'able can be asynchronous to the RedefineClasses() call since

  // the old method may still be running and cannot be GC'ed until

  // after all old invocations have finished. Additionally, a method

  // that has not been redefined may have an nmethod that depends on

  // the redefined method. The dependent nmethod will get deopted in

  // this case and may also be GC'able without the containing class

  // being unloaded.

  //

  // This flag indicates whether RedefineClasses() has ever redefined

  // one or more classes during the lifetime of the VM. The flag should

  // only be set by the friend class and can be queried by other sub

  // systems as needed to relax invariant checks.

  static bool _has_redefined_a_class;

  friend class VM_RedefineClasses;

  inline static void set_has_redefined_a_class() {

    _has_redefined_a_class = true;

  }

  // Flag to indicate if the compiler has recorded all dependencies. When the

  // can_redefine_classes capability is enabled in the OnLoad phase then the compiler

  // records all dependencies from startup. However if the capability is first

  // enabled some time later then the dependencies recorded by the compiler

  // are incomplete. This flag is used by RedefineClasses to know if the

  // dependency information is complete or not.

  static bool _all_dependencies_are_recorded;

 public:

  inline static bool has_redefined_a_class() {

    return _has_redefined_a_class;

  }

  inline static bool all_dependencies_are_recorded() {

    return _all_dependencies_are_recorded;

  }

  inline static void set_all_dependencies_are_recorded(bool on) {

    _all_dependencies_are_recorded = (on != 0);

  }

  // let JVMTI know that the JVM_OnLoad code is running

  static void enter_onload_phase();

  // let JVMTI know that the VM isn't up yet (and JVM_OnLoad code isn't running)

  static void enter_primordial_phase();

  // let JVMTI know that the VM isn't up yet but JNI is live

  static void enter_start_phase();

  // let JVMTI know that the VM is fully up and running now

  static void enter_live_phase();

  // ------ can_* conditions (below) are set at OnLoad and never changed ------------

  inline static bool can_modify_any_class()                       { return _can_modify_any_class; }

  inline static bool can_access_local_variables()                 { return _can_access_local_variables; }

  inline static bool can_hotswap_or_post_breakpoint()             { return _can_hotswap_or_post_breakpoint; }

  inline static bool can_walk_any_space()                         { return _can_walk_any_space; }

  // field access management

  static address  get_field_access_count_addr();

  // field modification management

  static address  get_field_modification_count_addr();

  // -----------------

  static bool is_jvmti_version(jint version)                      { return (version & JVMTI_VERSION_MASK) == JVMTI_VERSION_VALUE; }

  static bool is_jvmdi_version(jint version)                      { return (version & JVMTI_VERSION_MASK) == JVMDI_VERSION_VALUE; }

  static jint get_jvmti_interface(JavaVM *jvm, void **penv, jint version);

  static void decode_version_values(jint version, int * major, int * minor,

                                    int * micro);

  // single stepping management methods

  static void at_single_stepping_point(JavaThread *thread, methodOop method, address location) KERNEL_RETURN;

  static void expose_single_stepping(JavaThread *thread) KERNEL_RETURN;

  static bool hide_single_stepping(JavaThread *thread) KERNEL_RETURN_(return false;);

  // Methods that notify the debugger that something interesting has happened in the VM.

  static void post_vm_start              ();

  static void post_vm_initialized        ();

  static void post_vm_death              ();

  static void post_single_step           (JavaThread *thread, methodOop method, address location) KERNEL_RETURN;

  static void post_raw_breakpoint        (JavaThread *thread, methodOop method, address location) KERNEL_RETURN;

  static void post_exception_throw       (JavaThread *thread, methodOop method, address location, oop exception) KERNEL_RETURN;

  static void notice_unwind_due_to_exception (JavaThread *thread, methodOop method, address location, oop exception, bool in_handler_frame) KERNEL_RETURN;

  static oop jni_GetField_probe          (JavaThread *thread, jobject jobj,

    oop obj, klassOop klass, jfieldID fieldID, bool is_static)

    KERNEL_RETURN_(return NULL;);

  static oop jni_GetField_probe_nh       (JavaThread *thread, jobject jobj,

    oop obj, klassOop klass, jfieldID fieldID, bool is_static)

    KERNEL_RETURN_(return NULL;);

  static void post_field_access_by_jni   (JavaThread *thread, oop obj,

    klassOop klass, jfieldID fieldID, bool is_static) KERNEL_RETURN;

  static void post_field_access          (JavaThread *thread, methodOop method,

    address location, KlassHandle field_klass, Handle object, jfieldID field) KERNEL_RETURN;

  static oop jni_SetField_probe          (JavaThread *thread, jobject jobj,

    oop obj, klassOop klass, jfieldID fieldID, bool is_static, char sig_type,

    jvalue *value) KERNEL_RETURN_(return NULL;);

  static oop jni_SetField_probe_nh       (JavaThread *thread, jobject jobj,

    oop obj, klassOop klass, jfieldID fieldID, bool is_static, char sig_type,

    jvalue *value) KERNEL_RETURN_(return NULL;);

  static void post_field_modification_by_jni(JavaThread *thread, oop obj,

    klassOop klass, jfieldID fieldID, bool is_static, char sig_type,

    jvalue *value);

  static void post_raw_field_modification(JavaThread *thread, methodOop method,

    address location, KlassHandle field_klass, Handle object, jfieldID field,

    char sig_type, jvalue *value) KERNEL_RETURN;

  static void post_method_entry          (JavaThread *thread, methodOop method, frame current_frame) KERNEL_RETURN;

  static void post_method_exit           (JavaThread *thread, methodOop method, frame current_frame) KERNEL_RETURN;

  static void post_class_load            (JavaThread *thread, klassOop klass) KERNEL_RETURN;

  static void post_class_unload          (klassOop klass) KERNEL_RETURN;

  static void post_class_prepare         (JavaThread *thread, klassOop klass) KERNEL_RETURN;

  static void post_thread_start          (JavaThread *thread) KERNEL_RETURN;

  static void post_thread_end            (JavaThread *thread) KERNEL_RETURN;

  // Support for java.lang.instrument agent loading.

  static bool _should_post_class_file_load_hook;

  inline static void set_should_post_class_file_load_hook(bool on)     { _should_post_class_file_load_hook = on;  }

  inline static bool should_post_class_file_load_hook()           { return _should_post_class_file_load_hook; }

  static void post_class_file_load_hook(symbolHandle h_name, Handle class_loader,

                                        Handle h_protection_domain,

                                        unsigned char **data_ptr, unsigned char **end_ptr,

                                        unsigned char **cached_data_ptr,

                                        jint *cached_length_ptr);

  static void post_native_method_bind(methodOop method, address* function_ptr) KERNEL_RETURN;

  static void post_compiled_method_load(nmethod *nm) KERNEL_RETURN;

  static void post_dynamic_code_generated(const char *name, const void *code_begin, const void *code_end) KERNEL_RETURN;

  // used to post a CompiledMethodUnload event

  static void post_compiled_method_unload(jmethodID mid, const void *code_begin) KERNEL_RETURN;

  // similiar to post_dynamic_code_generated except that it can be used to

  // post a DynamicCodeGenerated event while holding locks in the VM. Any event

  // posted using this function is recorded by the enclosing event collector

  // -- JvmtiDynamicCodeEventCollector.

  static void post_dynamic_code_generated_while_holding_locks(const char* name, address code_begin, address code_end) KERNEL_RETURN;

  static void post_garbage_collection_finish() KERNEL_RETURN;

  static void post_garbage_collection_start() KERNEL_RETURN;

  static void post_data_dump() KERNEL_RETURN;

  static void post_monitor_contended_enter(JavaThread *thread, ObjectMonitor *obj_mntr) KERNEL_RETURN;

  static void post_monitor_contended_entered(JavaThread *thread, ObjectMonitor *obj_mntr) KERNEL_RETURN;

  static void post_monitor_wait(JavaThread *thread, oop obj, jlong timeout) KERNEL_RETURN;

  static void post_monitor_waited(JavaThread *thread, ObjectMonitor *obj_mntr, jboolean timed_out) KERNEL_RETURN;

  static void post_object_free(JvmtiEnv* env, jlong tag) KERNEL_RETURN;

  static void post_resource_exhausted(jint resource_exhausted_flags, const char* detail) KERNEL_RETURN;

  static void record_vm_internal_object_allocation(oop object) KERNEL_RETURN;

  // Post objects collected by vm_object_alloc_event_collector.

  static void post_vm_object_alloc(JavaThread *thread, oop object) KERNEL_RETURN;

  // Collects vm internal objects for later event posting.

  inline static void vm_object_alloc_event_collector(oop object) {

    if (should_post_vm_object_alloc()) {

      record_vm_internal_object_allocation(object);

    }

  }

  static void cleanup_thread             (JavaThread* thread) KERNEL_RETURN;

  static void oops_do(OopClosure* f) KERNEL_RETURN;

  static void transition_pending_onload_raw_monitors() KERNEL_RETURN;

#ifndef SERVICES_KERNEL

  // attach support

  static jint load_agent_library(AttachOperation* op, outputStream* out);

#endif // SERVICES_KERNEL

  // SetNativeMethodPrefix support

  static char** get_all_native_method_prefixes(int* count_ptr);

  // call after CMS has completed referencing processing

  static void cms_ref_processing_epilogue() KERNEL_RETURN;

};

// Support class used by JvmtiDynamicCodeEventCollector and others. It

// describes a single code blob by name and address range.

class JvmtiCodeBlobDesc : public CHeapObj {

 private:

  char _name[64];

  address _code_begin;

  address _code_end;

 public:

  JvmtiCodeBlobDesc(const char *name, address code_begin, address code_end) {

    assert(name != NULL, "all code blobs must be named");

    strncpy(_name, name, sizeof(_name));

    _name[sizeof(_name)-1] = '\0';

    _code_begin = code_begin;

    _code_end = code_end;

  }

  char* name()                  { return _name; }

  address code_begin()          { return _code_begin; }

  address code_end()            { return _code_end; }

};

// JvmtiEventCollector is a helper class to setup thread for

// event collection.

class JvmtiEventCollector : public StackObj {

 private:

  JvmtiEventCollector* _prev;  // Save previous one to support nested event collector.

 public:

  void setup_jvmti_thread_state(); // Set this collector in current thread.

  void unset_jvmti_thread_state(); // Reset previous collector in current thread.

  virtual bool is_dynamic_code_event()   { return false; }

  virtual bool is_vm_object_alloc_event(){ return false; }

  JvmtiEventCollector *get_prev()        { return _prev; }

};

// A JvmtiDynamicCodeEventCollector is a helper class for the JvmtiExport

// interface. It collects "dynamic code generated" events that are posted

// while holding locks. When the event collector goes out of scope the

// events will be posted.

//

// Usage :-

//

// {

//   JvmtiDynamicCodeEventCollector event_collector;

//   :

//   { MutexLocker ml(...)

//     :

//     JvmtiExport::post_dynamic_code_generated_while_holding_locks(...)

//   }

//   // event collector goes out of scope => post events to profiler.

// }

class JvmtiDynamicCodeEventCollector : public JvmtiEventCollector {

 private:

  GrowableArray<JvmtiCodeBlobDesc*>* _code_blobs;           // collected code blob events

  friend class JvmtiExport;

  void register_stub(const char* name, address start, address end);

 public:

  JvmtiDynamicCodeEventCollector()  KERNEL_RETURN;

  ~JvmtiDynamicCodeEventCollector() KERNEL_RETURN;

  bool is_dynamic_code_event()   { return true; }

};

// Used to record vm internally allocated object oops and post

// vm object alloc event for objects visible to java world.

// Constructor enables JvmtiThreadState flag and all vm allocated

// objects are recorded in a growable array. When destructor is

// called the vm object alloc event is posted for each objects

// visible to java world.

// See jvm.cpp file for its usage.

//

class JvmtiVMObjectAllocEventCollector : public JvmtiEventCollector {

 private:

  GrowableArray<oop>* _allocated; // field to record vm internally allocated object oop.

  bool _enable;                   // This flag is enabled in constructor and disabled

                                  // in destructor before posting event. To avoid

                                  // collection of objects allocated while running java code inside

                                  // agent post_vm_object_alloc() event handler.

  //GC support

  void oops_do(OopClosure* f);

  friend class JvmtiExport;

  // Record vm allocated object oop.

  inline void record_allocation(oop obj);

  //GC support

  static void oops_do_for_all_threads(OopClosure* f);

 public:

  JvmtiVMObjectAllocEventCollector()  KERNEL_RETURN;

  ~JvmtiVMObjectAllocEventCollector() KERNEL_RETURN;

  bool is_vm_object_alloc_event()   { return true; }

  bool is_enabled()                 { return _enable; }

  void set_enabled(bool on)         { _enable = on; }

};

// Marker class to disable the posting of VMObjectAlloc events

// within its scope.

//

// Usage :-

//

// {

//   NoJvmtiVMObjectAllocMark njm;

//   :

//   // VMObjAlloc event will not be posted

//   JvmtiExport::vm_object_alloc_event_collector(obj);

//   :

// }

class NoJvmtiVMObjectAllocMark : public StackObj {

 private:

  // enclosing collector if enabled, NULL otherwise

  JvmtiVMObjectAllocEventCollector *_collector;

  bool was_enabled()    { return _collector != NULL; }

 public:

  NoJvmtiVMObjectAllocMark() KERNEL_RETURN;

  ~NoJvmtiVMObjectAllocMark() KERNEL_RETURN;

};

// Base class for reporting GC events to JVMTI.

class JvmtiGCMarker : public StackObj {

 private:

  bool _full;                           // marks a "full" GC

  unsigned int _invocation_count;       // GC invocation count

 protected:

  JvmtiGCMarker(bool full) KERNEL_RETURN;       // protected

  ~JvmtiGCMarker() KERNEL_RETURN;               // protected

};

// Support class used to report GC events to JVMTI. The class is stack

// allocated and should be placed in the doit() implementation of all

// vm operations that do a stop-the-world GC for failed allocation.

//

// Usage :-

//

// void VM_GenCollectForAllocation::doit() {

//   JvmtiGCForAllocationMarker jgcm;

//   :

// }

//

// If jvmti is not enabled the constructor and destructor is essentially

// a no-op (no overhead).

//

class JvmtiGCForAllocationMarker : public JvmtiGCMarker {

 public:

  JvmtiGCForAllocationMarker() : JvmtiGCMarker(false) {

  }

};

// Support class used to report GC events to JVMTI. The class is stack

// allocated and should be placed in the doit() implementation of all

// vm operations that do a "full" stop-the-world GC. This class differs

// from JvmtiGCForAllocationMarker in that this class assumes that a

// "full" GC will happen.