1 /*
   2  * Copyright (c) 2003, 2023, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classLoaderExt.hpp"
  27 #include "classfile/javaClasses.inline.hpp"
  28 #include "classfile/stringTable.hpp"
  29 #include "classfile/modules.hpp"
  30 #include "classfile/systemDictionary.hpp"
  31 #include "classfile/vmClasses.hpp"
  32 #include "classfile/vmSymbols.hpp"
  33 #include "gc/shared/collectedHeap.hpp"
  34 #include "interpreter/bytecodeStream.hpp"
  35 #include "interpreter/interpreter.hpp"
  36 #include "jfr/jfrEvents.hpp"
  37 #include "jvmtifiles/jvmtiEnv.hpp"
  38 #include "logging/log.hpp"
  39 #include "logging/logConfiguration.hpp"
  40 #include "memory/allocation.hpp"
  41 #include "memory/resourceArea.hpp"
  42 #include "memory/universe.hpp"
  43 #include "oops/instanceKlass.hpp"
  44 #include "oops/klass.inline.hpp"
  45 #include "oops/objArrayOop.inline.hpp"
  46 #include "oops/oop.inline.hpp"
  47 #include "prims/jniCheck.hpp"
  48 #include "prims/jvm_misc.hpp"
  49 #include "prims/jvmtiAgentThread.hpp"
  50 #include "prims/jvmtiClassFileReconstituter.hpp"
  51 #include "prims/jvmtiCodeBlobEvents.hpp"
  52 #include "prims/jvmtiExtensions.hpp"
  53 #include "prims/jvmtiGetLoadedClasses.hpp"
  54 #include "prims/jvmtiImpl.hpp"
  55 #include "prims/jvmtiManageCapabilities.hpp"
  56 #include "prims/jvmtiRawMonitor.hpp"
  57 #include "prims/jvmtiRedefineClasses.hpp"
  58 #include "prims/jvmtiTagMap.hpp"
  59 #include "prims/jvmtiThreadState.inline.hpp"
  60 #include "prims/jvmtiUtil.hpp"
  61 #include "runtime/arguments.hpp"
  62 #include "runtime/deoptimization.hpp"
  63 #include "runtime/fieldDescriptor.inline.hpp"
  64 #include "runtime/handles.inline.hpp"
  65 #include "runtime/interfaceSupport.inline.hpp"
  66 #include "runtime/javaCalls.hpp"
  67 #include "runtime/javaThread.inline.hpp"
  68 #include "runtime/jfieldIDWorkaround.hpp"
  69 #include "runtime/jniHandles.inline.hpp"
  70 #include "runtime/objectMonitor.inline.hpp"
  71 #include "runtime/os.hpp"
  72 #include "runtime/osThread.hpp"
  73 #include "runtime/reflectionUtils.hpp"
  74 #include "runtime/signature.hpp"
  75 #include "runtime/threadHeapSampler.hpp"
  76 #include "runtime/threads.hpp"
  77 #include "runtime/threadSMR.hpp"
  78 #include "runtime/timerTrace.hpp"
  79 #include "runtime/vframe.inline.hpp"
  80 #include "runtime/vmThread.hpp"
  81 #include "services/threadService.hpp"
  82 #include "utilities/exceptions.hpp"
  83 #include "utilities/preserveException.hpp"
  84 #include "utilities/utf8.hpp"
  85 
  86 
  87 #define FIXLATER 0 // REMOVE this when completed.
  88 
  89  // FIXLATER: hook into JvmtiTrace
  90 #define TraceJVMTICalls false
  91 
  92 JvmtiEnv::JvmtiEnv(jint version) : JvmtiEnvBase(version) {
  93 }
  94 
  95 JvmtiEnv::~JvmtiEnv() {
  96 }
  97 
  98 JvmtiEnv*
  99 JvmtiEnv::create_a_jvmti(jint version) {
 100   return new JvmtiEnv(version);
 101 }
 102 
 103 // VM operation class to copy jni function table at safepoint.
 104 // More than one java threads or jvmti agents may be reading/
 105 // modifying jni function tables. To reduce the risk of bad
 106 // interaction b/w these threads it is copied at safepoint.
 107 class VM_JNIFunctionTableCopier : public VM_Operation {
 108  private:
 109   const struct JNINativeInterface_ *_function_table;
 110  public:
 111   VM_JNIFunctionTableCopier(const struct JNINativeInterface_ *func_tbl) {
 112     _function_table = func_tbl;
 113   };
 114 
 115   VMOp_Type type() const { return VMOp_JNIFunctionTableCopier; }
 116   void doit() {
 117     copy_jni_function_table(_function_table);
 118   };
 119 };
 120 
 121 //
 122 // Do not change the "prefix" marker below, everything above it is copied
 123 // unchanged into the filled stub, everything below is controlled by the
 124 // stub filler (only method bodies are carried forward, and then only for
 125 // functionality still in the spec).
 126 //
 127 // end file prefix
 128 
 129   //
 130   // Memory Management functions
 131   //
 132 
 133 // mem_ptr - pre-checked for null
 134 jvmtiError
 135 JvmtiEnv::Allocate(jlong size, unsigned char** mem_ptr) {
 136   return allocate(size, mem_ptr);
 137 } /* end Allocate */
 138 
 139 
 140 // mem - null is a valid value, must be checked
 141 jvmtiError
 142 JvmtiEnv::Deallocate(unsigned char* mem) {
 143   return deallocate(mem);
 144 } /* end Deallocate */
 145 
 146 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
 147 // data - null is a valid value, must be checked
 148 jvmtiError
 149 JvmtiEnv::SetThreadLocalStorage(jthread thread, const void* data) {
 150   JavaThread* current = JavaThread::current();
 151   JvmtiThreadState* state = nullptr;
 152   JvmtiVTMSTransitionDisabler disabler(thread);
 153   ThreadsListHandle tlh(current);
 154 
 155   JavaThread* java_thread = nullptr;
 156   oop thread_obj = nullptr;
 157   if (thread == nullptr) {
 158     java_thread = current;
 159     state = java_thread->jvmti_thread_state();
 160   } else {
 161     jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
 162     if (err != JVMTI_ERROR_NONE) {
 163       return err;
 164     }
 165     state = java_lang_Thread::jvmti_thread_state(thread_obj);
 166   }
 167   if (state == nullptr) {
 168     if (data == nullptr) {
 169       // leaving state unset same as data set to null
 170       return JVMTI_ERROR_NONE;
 171     }
 172     // otherwise, create the state
 173     HandleMark hm(current);
 174     Handle thread_handle(current, thread_obj);
 175     state = JvmtiThreadState::state_for(java_thread, thread_handle);
 176     if (state == nullptr) {
 177       return JVMTI_ERROR_THREAD_NOT_ALIVE;
 178     }
 179   }
 180   state->env_thread_state(this)->set_agent_thread_local_storage_data((void*)data);
 181   return JVMTI_ERROR_NONE;
 182 } /* end SetThreadLocalStorage */
 183 
 184 
 185 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
 186 // data_ptr - pre-checked for null
 187 jvmtiError
 188 JvmtiEnv::GetThreadLocalStorage(jthread thread, void** data_ptr) {
 189   JavaThread* current_thread = JavaThread::current();
 190   if (thread == nullptr) {
 191     JvmtiThreadState* state = current_thread->jvmti_thread_state();
 192     *data_ptr = (state == nullptr) ? nullptr :
 193       state->env_thread_state(this)->get_agent_thread_local_storage_data();
 194   } else {
 195     // jvmti_GetThreadLocalStorage is "in native" and doesn't transition
 196     // the thread to _thread_in_vm. However, when the TLS for a thread
 197     // other than the current thread is required we need to transition
 198     // from native so as to resolve the jthread.
 199 
 200     MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, current_thread));
 201     ThreadInVMfromNative __tiv(current_thread);
 202     VM_ENTRY_BASE(jvmtiError, JvmtiEnv::GetThreadLocalStorage , current_thread)
 203     debug_only(VMNativeEntryWrapper __vew;)
 204 
 205     JvmtiVTMSTransitionDisabler disabler(thread);
 206     ThreadsListHandle tlh(current_thread);
 207 
 208     JavaThread* java_thread = nullptr;
 209     oop thread_obj = nullptr;
 210     jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
 211     if (err != JVMTI_ERROR_NONE) {
 212       return err;
 213     }
 214 
 215     HandleMark hm(current_thread);
 216     Handle thread_handle(current_thread, thread_obj);
 217     JvmtiThreadState* state = JvmtiThreadState::state_for(java_thread, thread_handle);
 218     *data_ptr = (state == nullptr) ? nullptr :
 219       state->env_thread_state(this)->get_agent_thread_local_storage_data();
 220   }
 221   return JVMTI_ERROR_NONE;
 222 } /* end GetThreadLocalStorage */
 223 
 224   //
 225   // Module functions
 226   //
 227 
 228 // module_count_ptr - pre-checked for null
 229 // modules_ptr - pre-checked for null
 230 jvmtiError
 231 JvmtiEnv::GetAllModules(jint* module_count_ptr, jobject** modules_ptr) {
 232     JvmtiModuleClosure jmc;
 233 
 234     return jmc.get_all_modules(this, module_count_ptr, modules_ptr);
 235 } /* end GetAllModules */
 236 
 237 
 238 // class_loader - null is a valid value, must be pre-checked
 239 // package_name - pre-checked for null
 240 // module_ptr - pre-checked for null
 241 jvmtiError
 242 JvmtiEnv::GetNamedModule(jobject class_loader, const char* package_name, jobject* module_ptr) {
 243   JavaThread* THREAD = JavaThread::current(); // For exception macros.
 244   ResourceMark rm(THREAD);
 245 
 246   Handle h_loader (THREAD, JNIHandles::resolve(class_loader));
 247   // Check that loader is a subclass of java.lang.ClassLoader.
 248   if (h_loader.not_null() && !java_lang_ClassLoader::is_subclass(h_loader->klass())) {
 249     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 250   }
 251   oop module = Modules::get_named_module(h_loader, package_name);
 252   *module_ptr = module != nullptr ? JNIHandles::make_local(THREAD, module) : nullptr;
 253   return JVMTI_ERROR_NONE;
 254 } /* end GetNamedModule */
 255 
 256 
 257 // module - pre-checked for null
 258 // to_module - pre-checked for null
 259 jvmtiError
 260 JvmtiEnv::AddModuleReads(jobject module, jobject to_module) {
 261   JavaThread* THREAD = JavaThread::current(); // For exception macros.
 262 
 263   // check module
 264   Handle h_module(THREAD, JNIHandles::resolve(module));
 265   if (!java_lang_Module::is_instance(h_module())) {
 266     return JVMTI_ERROR_INVALID_MODULE;
 267   }
 268   // check to_module
 269   Handle h_to_module(THREAD, JNIHandles::resolve(to_module));
 270   if (!java_lang_Module::is_instance(h_to_module())) {
 271     return JVMTI_ERROR_INVALID_MODULE;
 272   }
 273   return JvmtiExport::add_module_reads(h_module, h_to_module, THREAD);
 274 } /* end AddModuleReads */
 275 
 276 
 277 // module - pre-checked for null
 278 // pkg_name - pre-checked for null
 279 // to_module - pre-checked for null
 280 jvmtiError
 281 JvmtiEnv::AddModuleExports(jobject module, const char* pkg_name, jobject to_module) {
 282   JavaThread* THREAD = JavaThread::current(); // For exception macros.
 283   Handle h_pkg = java_lang_String::create_from_str(pkg_name, THREAD);
 284 
 285   // check module
 286   Handle h_module(THREAD, JNIHandles::resolve(module));
 287   if (!java_lang_Module::is_instance(h_module())) {
 288     return JVMTI_ERROR_INVALID_MODULE;
 289   }
 290   // check to_module
 291   Handle h_to_module(THREAD, JNIHandles::resolve(to_module));
 292   if (!java_lang_Module::is_instance(h_to_module())) {
 293     return JVMTI_ERROR_INVALID_MODULE;
 294   }
 295   return JvmtiExport::add_module_exports(h_module, h_pkg, h_to_module, THREAD);
 296 } /* end AddModuleExports */
 297 
 298 
 299 // module - pre-checked for null
 300 // pkg_name - pre-checked for null
 301 // to_module - pre-checked for null
 302 jvmtiError
 303 JvmtiEnv::AddModuleOpens(jobject module, const char* pkg_name, jobject to_module) {
 304   JavaThread* THREAD = JavaThread::current(); // For exception macros.
 305   Handle h_pkg = java_lang_String::create_from_str(pkg_name, THREAD);
 306 
 307   // check module
 308   Handle h_module(THREAD, JNIHandles::resolve(module));
 309   if (!java_lang_Module::is_instance(h_module())) {
 310     return JVMTI_ERROR_INVALID_MODULE;
 311   }
 312   // check to_module
 313   Handle h_to_module(THREAD, JNIHandles::resolve(to_module));
 314   if (!java_lang_Module::is_instance(h_to_module())) {
 315     return JVMTI_ERROR_INVALID_MODULE;
 316   }
 317   return JvmtiExport::add_module_opens(h_module, h_pkg, h_to_module, THREAD);
 318 } /* end AddModuleOpens */
 319 
 320 
 321 // module - pre-checked for null
 322 // service - pre-checked for null
 323 jvmtiError
 324 JvmtiEnv::AddModuleUses(jobject module, jclass service) {
 325   JavaThread* THREAD = JavaThread::current(); // For exception macros.
 326 
 327   // check module
 328   Handle h_module(THREAD, JNIHandles::resolve(module));
 329   if (!java_lang_Module::is_instance(h_module())) {
 330     return JVMTI_ERROR_INVALID_MODULE;
 331   }
 332   // check service
 333   Handle h_service(THREAD, JNIHandles::resolve_external_guard(service));
 334   if (!java_lang_Class::is_instance(h_service()) ||
 335       java_lang_Class::is_primitive(h_service())) {
 336     return JVMTI_ERROR_INVALID_CLASS;
 337   }
 338   return JvmtiExport::add_module_uses(h_module, h_service, THREAD);
 339 } /* end AddModuleUses */
 340 
 341 
 342 // module - pre-checked for null
 343 // service - pre-checked for null
 344 // impl_class - pre-checked for null
 345 jvmtiError
 346 JvmtiEnv::AddModuleProvides(jobject module, jclass service, jclass impl_class) {
 347   JavaThread* THREAD = JavaThread::current(); // For exception macros.
 348 
 349   // check module
 350   Handle h_module(THREAD, JNIHandles::resolve(module));
 351   if (!java_lang_Module::is_instance(h_module())) {
 352     return JVMTI_ERROR_INVALID_MODULE;
 353   }
 354   // check service
 355   Handle h_service(THREAD, JNIHandles::resolve_external_guard(service));
 356   if (!java_lang_Class::is_instance(h_service()) ||
 357       java_lang_Class::is_primitive(h_service())) {
 358     return JVMTI_ERROR_INVALID_CLASS;
 359   }
 360   // check impl_class
 361   Handle h_impl_class(THREAD, JNIHandles::resolve_external_guard(impl_class));
 362   if (!java_lang_Class::is_instance(h_impl_class()) ||
 363       java_lang_Class::is_primitive(h_impl_class())) {
 364     return JVMTI_ERROR_INVALID_CLASS;
 365   }
 366   return JvmtiExport::add_module_provides(h_module, h_service, h_impl_class, THREAD);
 367 } /* end AddModuleProvides */
 368 
 369 // module - pre-checked for null
 370 // is_modifiable_class_ptr - pre-checked for null
 371 jvmtiError
 372 JvmtiEnv::IsModifiableModule(jobject module, jboolean* is_modifiable_module_ptr) {
 373   JavaThread* current = JavaThread::current();
 374 
 375   // check module
 376   Handle h_module(current, JNIHandles::resolve(module));
 377   if (!java_lang_Module::is_instance(h_module())) {
 378     return JVMTI_ERROR_INVALID_MODULE;
 379   }
 380 
 381   *is_modifiable_module_ptr = JNI_TRUE;
 382   return JVMTI_ERROR_NONE;
 383 } /* end IsModifiableModule */
 384 
 385 
 386   //
 387   // Class functions
 388   //
 389 
 390 // class_count_ptr - pre-checked for null
 391 // classes_ptr - pre-checked for null
 392 jvmtiError
 393 JvmtiEnv::GetLoadedClasses(jint* class_count_ptr, jclass** classes_ptr) {
 394   return JvmtiGetLoadedClasses::getLoadedClasses(this, class_count_ptr, classes_ptr);
 395 } /* end GetLoadedClasses */
 396 
 397 
 398 // initiating_loader - null is a valid value, must be checked
 399 // class_count_ptr - pre-checked for null
 400 // classes_ptr - pre-checked for null
 401 jvmtiError
 402 JvmtiEnv::GetClassLoaderClasses(jobject initiating_loader, jint* class_count_ptr, jclass** classes_ptr) {
 403   return JvmtiGetLoadedClasses::getClassLoaderClasses(this, initiating_loader,
 404                                                   class_count_ptr, classes_ptr);
 405 } /* end GetClassLoaderClasses */
 406 
 407 // k_mirror - may be primitive, this must be checked
 408 // is_modifiable_class_ptr - pre-checked for null
 409 jvmtiError
 410 JvmtiEnv::IsModifiableClass(oop k_mirror, jboolean* is_modifiable_class_ptr) {
 411   *is_modifiable_class_ptr = VM_RedefineClasses::is_modifiable_class(k_mirror)?
 412                                                        JNI_TRUE : JNI_FALSE;
 413   return JVMTI_ERROR_NONE;
 414 } /* end IsModifiableClass */
 415 
 416 // class_count - pre-checked to be greater than or equal to 0
 417 // classes - pre-checked for null
 418 jvmtiError
 419 JvmtiEnv::RetransformClasses(jint class_count, const jclass* classes) {
 420 //TODO: add locking
 421 
 422   int index;
 423   JavaThread* current_thread = JavaThread::current();
 424   ResourceMark rm(current_thread);
 425 
 426   jvmtiClassDefinition* class_definitions =
 427                             NEW_RESOURCE_ARRAY(jvmtiClassDefinition, class_count);
 428   NULL_CHECK(class_definitions, JVMTI_ERROR_OUT_OF_MEMORY);
 429 
 430   for (index = 0; index < class_count; index++) {
 431     HandleMark hm(current_thread);
 432 
 433     jclass jcls = classes[index];
 434     oop k_mirror = JNIHandles::resolve_external_guard(jcls);
 435     if (k_mirror == nullptr) {
 436       return JVMTI_ERROR_INVALID_CLASS;
 437     }
 438     if (!k_mirror->is_a(vmClasses::Class_klass())) {
 439       return JVMTI_ERROR_INVALID_CLASS;
 440     }
 441 
 442     if (!VM_RedefineClasses::is_modifiable_class(k_mirror)) {
 443       return JVMTI_ERROR_UNMODIFIABLE_CLASS;
 444     }
 445 
 446     Klass* klass = java_lang_Class::as_Klass(k_mirror);
 447 
 448     jint status = klass->jvmti_class_status();
 449     if (status & (JVMTI_CLASS_STATUS_ERROR)) {
 450       return JVMTI_ERROR_INVALID_CLASS;
 451     }
 452 
 453     InstanceKlass* ik = InstanceKlass::cast(klass);
 454     if (ik->get_cached_class_file_bytes() == nullptr) {
 455       // Not cached, we need to reconstitute the class file from the
 456       // VM representation. We don't attach the reconstituted class
 457       // bytes to the InstanceKlass here because they have not been
 458       // validated and we're not at a safepoint.
 459       JvmtiClassFileReconstituter reconstituter(ik);
 460       if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
 461         return reconstituter.get_error();
 462       }
 463 
 464       class_definitions[index].class_byte_count = (jint)reconstituter.class_file_size();
 465       class_definitions[index].class_bytes      = (unsigned char*)
 466                                                        reconstituter.class_file_bytes();
 467     } else {
 468       // it is cached, get it from the cache
 469       class_definitions[index].class_byte_count = ik->get_cached_class_file_len();
 470       class_definitions[index].class_bytes      = ik->get_cached_class_file_bytes();
 471     }
 472     class_definitions[index].klass              = jcls;
 473   }
 474   EventRetransformClasses event;
 475   VM_RedefineClasses op(class_count, class_definitions, jvmti_class_load_kind_retransform);
 476   VMThread::execute(&op);
 477   jvmtiError error = op.check_error();
 478   if (error == JVMTI_ERROR_NONE) {
 479     event.set_classCount(class_count);
 480     event.set_redefinitionId(op.id());
 481     event.commit();
 482   }
 483   return error;
 484 } /* end RetransformClasses */
 485 
 486 
 487 // class_count - pre-checked to be greater than or equal to 0
 488 // class_definitions - pre-checked for null
 489 jvmtiError
 490 JvmtiEnv::RedefineClasses(jint class_count, const jvmtiClassDefinition* class_definitions) {
 491 //TODO: add locking
 492   EventRedefineClasses event;
 493   VM_RedefineClasses op(class_count, class_definitions, jvmti_class_load_kind_redefine);
 494   VMThread::execute(&op);
 495   jvmtiError error = op.check_error();
 496   if (error == JVMTI_ERROR_NONE) {
 497     event.set_classCount(class_count);
 498     event.set_redefinitionId(op.id());
 499     event.commit();
 500   }
 501   return error;
 502 } /* end RedefineClasses */
 503 
 504 
 505   //
 506   // Object functions
 507   //
 508 
 509 // size_ptr - pre-checked for null
 510 jvmtiError
 511 JvmtiEnv::GetObjectSize(jobject object, jlong* size_ptr) {
 512   oop mirror = JNIHandles::resolve_external_guard(object);
 513   NULL_CHECK(mirror, JVMTI_ERROR_INVALID_OBJECT);
 514   *size_ptr = (jlong)mirror->size() * wordSize;
 515   return JVMTI_ERROR_NONE;
 516 } /* end GetObjectSize */
 517 
 518   //
 519   // Method functions
 520   //
 521 
 522 // prefix - null is a valid value, must be checked
 523 jvmtiError
 524 JvmtiEnv::SetNativeMethodPrefix(const char* prefix) {
 525   return prefix == nullptr?
 526               SetNativeMethodPrefixes(0, nullptr) :
 527               SetNativeMethodPrefixes(1, (char**)&prefix);
 528 } /* end SetNativeMethodPrefix */
 529 
 530 
 531 // prefix_count - pre-checked to be greater than or equal to 0
 532 // prefixes - pre-checked for null
 533 jvmtiError
 534 JvmtiEnv::SetNativeMethodPrefixes(jint prefix_count, char** prefixes) {
 535   // Have to grab JVMTI thread state lock to be sure that some thread
 536   // isn't accessing the prefixes at the same time we are setting them.
 537   // No locks during VM bring-up.
 538   if (Threads::number_of_threads() == 0) {
 539     return set_native_method_prefixes(prefix_count, prefixes);
 540   } else {
 541     MutexLocker mu(JvmtiThreadState_lock);
 542     return set_native_method_prefixes(prefix_count, prefixes);
 543   }
 544 } /* end SetNativeMethodPrefixes */
 545 
 546   //
 547   // Event Management functions
 548   //
 549 
 550 // callbacks - null is a valid value, must be checked
 551 // size_of_callbacks - pre-checked to be greater than or equal to 0
 552 jvmtiError
 553 JvmtiEnv::SetEventCallbacks(const jvmtiEventCallbacks* callbacks, jint size_of_callbacks) {
 554   JvmtiVTMSTransitionDisabler disabler;
 555   JvmtiEventController::set_event_callbacks(this, callbacks, size_of_callbacks);
 556   return JVMTI_ERROR_NONE;
 557 } /* end SetEventCallbacks */
 558 
 559 
 560 // event_thread - null is a valid value, must be checked
 561 jvmtiError
 562 JvmtiEnv::SetEventNotificationMode(jvmtiEventMode mode, jvmtiEvent event_type, jthread event_thread,   ...) {
 563   bool enabled = (mode == JVMTI_ENABLE);
 564 
 565   // event_type must be valid
 566   if (!JvmtiEventController::is_valid_event_type(event_type)) {
 567     return JVMTI_ERROR_INVALID_EVENT_TYPE;
 568   }
 569 
 570   // assure that needed capabilities are present
 571   if (enabled && !JvmtiUtil::has_event_capability(event_type, get_capabilities())) {
 572     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
 573   }
 574 
 575   if (event_type == JVMTI_EVENT_CLASS_FILE_LOAD_HOOK && enabled) {
 576     record_class_file_load_hook_enabled();
 577   }
 578   JvmtiVTMSTransitionDisabler disabler;
 579 
 580   if (event_thread == nullptr) {
 581     // Can be called at Agent_OnLoad() time with event_thread == nullptr
 582     // when Thread::current() does not work yet so we cannot create a
 583     // ThreadsListHandle that is common to both thread-specific and
 584     // global code paths.
 585 
 586     JvmtiEventController::set_user_enabled(this, nullptr, (oop) nullptr, event_type, enabled);
 587   } else {
 588     // We have a specified event_thread.
 589     ThreadsListHandle tlh;
 590 
 591     JavaThread* java_thread = nullptr;
 592     oop thread_obj = nullptr;
 593     jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), event_thread, &java_thread, &thread_obj);
 594     if (err != JVMTI_ERROR_NONE) {
 595       return err;
 596     }
 597 
 598     // global events cannot be controlled at thread level.
 599     if (JvmtiEventController::is_global_event(event_type)) {
 600       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 601     }
 602 
 603     JvmtiEventController::set_user_enabled(this, java_thread, thread_obj, event_type, enabled);
 604   }
 605 
 606   return JVMTI_ERROR_NONE;
 607 } /* end SetEventNotificationMode */
 608 
 609   //
 610   // Capability functions
 611   //
 612 
 613 // capabilities_ptr - pre-checked for null
 614 jvmtiError
 615 JvmtiEnv::GetPotentialCapabilities(jvmtiCapabilities* capabilities_ptr) {
 616   JvmtiManageCapabilities::get_potential_capabilities(get_capabilities(),
 617                                                       get_prohibited_capabilities(),
 618                                                       capabilities_ptr);
 619   return JVMTI_ERROR_NONE;
 620 } /* end GetPotentialCapabilities */
 621 
 622 
 623 // capabilities_ptr - pre-checked for null
 624 jvmtiError
 625 JvmtiEnv::AddCapabilities(const jvmtiCapabilities* capabilities_ptr) {
 626   return JvmtiManageCapabilities::add_capabilities(get_capabilities(),
 627                                                    get_prohibited_capabilities(),
 628                                                    capabilities_ptr,
 629                                                    get_capabilities());
 630 } /* end AddCapabilities */
 631 
 632 
 633 // capabilities_ptr - pre-checked for null
 634 jvmtiError
 635 JvmtiEnv::RelinquishCapabilities(const jvmtiCapabilities* capabilities_ptr) {
 636   JvmtiManageCapabilities::relinquish_capabilities(get_capabilities(), capabilities_ptr, get_capabilities());
 637   return JVMTI_ERROR_NONE;
 638 } /* end RelinquishCapabilities */
 639 
 640 
 641 // capabilities_ptr - pre-checked for null
 642 jvmtiError
 643 JvmtiEnv::GetCapabilities(jvmtiCapabilities* capabilities_ptr) {
 644   JvmtiManageCapabilities::copy_capabilities(get_capabilities(), capabilities_ptr);
 645   return JVMTI_ERROR_NONE;
 646 } /* end GetCapabilities */
 647 
 648   //
 649   // Class Loader Search functions
 650   //
 651 
 652 // segment - pre-checked for null
 653 jvmtiError
 654 JvmtiEnv::AddToBootstrapClassLoaderSearch(const char* segment) {
 655   jvmtiPhase phase = get_phase();
 656   if (phase == JVMTI_PHASE_ONLOAD) {
 657     Arguments::append_sysclasspath(segment);
 658     return JVMTI_ERROR_NONE;
 659   } else if (use_version_1_0_semantics()) {
 660     // This JvmtiEnv requested version 1.0 semantics and this function
 661     // is only allowed in the ONLOAD phase in version 1.0 so we need to
 662     // return an error here.
 663     return JVMTI_ERROR_WRONG_PHASE;
 664   } else if (phase == JVMTI_PHASE_LIVE) {
 665     // The phase is checked by the wrapper that called this function,
 666     // but this thread could be racing with the thread that is
 667     // terminating the VM so we check one more time.
 668 
 669     // create the zip entry
 670     ClassPathZipEntry* zip_entry = ClassLoader::create_class_path_zip_entry(segment, true);
 671     if (zip_entry == nullptr) {
 672       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 673     }
 674 
 675     // add the jar file to the bootclasspath
 676     log_info(class, load)("opened: %s", zip_entry->name());
 677 #if INCLUDE_CDS
 678     ClassLoaderExt::append_boot_classpath(zip_entry);
 679 #else
 680     ClassLoader::add_to_boot_append_entries(zip_entry);
 681 #endif
 682     return JVMTI_ERROR_NONE;
 683   } else {
 684     return JVMTI_ERROR_WRONG_PHASE;
 685   }
 686 
 687 } /* end AddToBootstrapClassLoaderSearch */
 688 
 689 
 690 // segment - pre-checked for null
 691 jvmtiError
 692 JvmtiEnv::AddToSystemClassLoaderSearch(const char* segment) {
 693   jvmtiPhase phase = get_phase();
 694 
 695   if (phase == JVMTI_PHASE_ONLOAD) {
 696     for (SystemProperty* p = Arguments::system_properties(); p != nullptr; p = p->next()) {
 697       if (strcmp("java.class.path", p->key()) == 0) {
 698         p->append_value(segment);
 699         break;
 700       }
 701     }
 702     return JVMTI_ERROR_NONE;
 703   } else if (phase == JVMTI_PHASE_LIVE) {
 704     // The phase is checked by the wrapper that called this function,
 705     // but this thread could be racing with the thread that is
 706     // terminating the VM so we check one more time.
 707     JavaThread* THREAD = JavaThread::current(); // For exception macros.
 708     HandleMark hm(THREAD);
 709 
 710     // create the zip entry (which will open the zip file and hence
 711     // check that the segment is indeed a zip file).
 712     ClassPathZipEntry* zip_entry = ClassLoader::create_class_path_zip_entry(segment, false);
 713     if (zip_entry == nullptr) {
 714       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 715     }
 716     delete zip_entry;   // no longer needed
 717 
 718     Handle loader(THREAD, SystemDictionary::java_system_loader());
 719 
 720     // need the path as java.lang.String
 721     Handle path = java_lang_String::create_from_platform_dependent_str(segment, THREAD);
 722     if (HAS_PENDING_EXCEPTION) {
 723       CLEAR_PENDING_EXCEPTION;
 724       return JVMTI_ERROR_INTERNAL;
 725     }
 726 
 727     // Invoke the appendToClassPathForInstrumentation method - if the method
 728     // is not found it means the loader doesn't support adding to the class path
 729     // in the live phase.
 730     {
 731       JavaValue res(T_VOID);
 732       JavaCalls::call_special(&res,
 733                               loader,
 734                               loader->klass(),
 735                               vmSymbols::appendToClassPathForInstrumentation_name(),
 736                               vmSymbols::appendToClassPathForInstrumentation_signature(),
 737                               path,
 738                               THREAD);
 739       if (HAS_PENDING_EXCEPTION) {
 740         Symbol* ex_name = PENDING_EXCEPTION->klass()->name();
 741         CLEAR_PENDING_EXCEPTION;
 742 
 743         if (ex_name == vmSymbols::java_lang_NoSuchMethodError()) {
 744           return JVMTI_ERROR_CLASS_LOADER_UNSUPPORTED;
 745         } else {
 746           return JVMTI_ERROR_INTERNAL;
 747         }
 748       }
 749     }
 750 
 751     return JVMTI_ERROR_NONE;
 752   } else {
 753     return JVMTI_ERROR_WRONG_PHASE;
 754   }
 755 } /* end AddToSystemClassLoaderSearch */
 756 
 757   //
 758   // General functions
 759   //
 760 
 761 // phase_ptr - pre-checked for null
 762 jvmtiError
 763 JvmtiEnv::GetPhase(jvmtiPhase* phase_ptr) {
 764   *phase_ptr = phase();
 765   return JVMTI_ERROR_NONE;
 766 } /* end GetPhase */
 767 
 768 
 769 jvmtiError
 770 JvmtiEnv::DisposeEnvironment() {
 771   dispose();
 772   return JVMTI_ERROR_NONE;
 773 } /* end DisposeEnvironment */
 774 
 775 
 776 // data - null is a valid value, must be checked
 777 jvmtiError
 778 JvmtiEnv::SetEnvironmentLocalStorage(const void* data) {
 779   set_env_local_storage(data);
 780   return JVMTI_ERROR_NONE;
 781 } /* end SetEnvironmentLocalStorage */
 782 
 783 
 784 // data_ptr - pre-checked for null
 785 jvmtiError
 786 JvmtiEnv::GetEnvironmentLocalStorage(void** data_ptr) {
 787   *data_ptr = (void*)get_env_local_storage();
 788   return JVMTI_ERROR_NONE;
 789 } /* end GetEnvironmentLocalStorage */
 790 
 791 // version_ptr - pre-checked for null
 792 jvmtiError
 793 JvmtiEnv::GetVersionNumber(jint* version_ptr) {
 794   *version_ptr = JVMTI_VERSION;
 795   return JVMTI_ERROR_NONE;
 796 } /* end GetVersionNumber */
 797 
 798 
 799 // name_ptr - pre-checked for null
 800 jvmtiError
 801 JvmtiEnv::GetErrorName(jvmtiError error, char** name_ptr) {
 802   if (error < JVMTI_ERROR_NONE || error > JVMTI_ERROR_MAX) {
 803     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 804   }
 805   const char *name = JvmtiUtil::error_name(error);
 806   if (name == nullptr) {
 807     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 808   }
 809   size_t len = strlen(name) + 1;
 810   jvmtiError err = allocate(len, (unsigned char**)name_ptr);
 811   if (err == JVMTI_ERROR_NONE) {
 812     memcpy(*name_ptr, name, len);
 813   }
 814   return err;
 815 } /* end GetErrorName */
 816 
 817 
 818 jvmtiError
 819 JvmtiEnv::SetVerboseFlag(jvmtiVerboseFlag flag, jboolean value) {
 820   LogLevelType level = value == 0 ? LogLevel::Off : LogLevel::Info;
 821   switch (flag) {
 822   case JVMTI_VERBOSE_OTHER:
 823     // ignore
 824     break;
 825   case JVMTI_VERBOSE_CLASS:
 826     LogConfiguration::configure_stdout(level, false, LOG_TAGS(class, unload));
 827     LogConfiguration::configure_stdout(level, false, LOG_TAGS(class, load));
 828     break;
 829   case JVMTI_VERBOSE_GC:
 830     LogConfiguration::configure_stdout(level, true, LOG_TAGS(gc));
 831     break;
 832   case JVMTI_VERBOSE_JNI:
 833     level = value == 0 ? LogLevel::Off : LogLevel::Debug;
 834     LogConfiguration::configure_stdout(level, true, LOG_TAGS(jni, resolve));
 835     break;
 836   default:
 837     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 838   };
 839   return JVMTI_ERROR_NONE;
 840 } /* end SetVerboseFlag */
 841 
 842 
 843 // format_ptr - pre-checked for null
 844 jvmtiError
 845 JvmtiEnv::GetJLocationFormat(jvmtiJlocationFormat* format_ptr) {
 846   *format_ptr = JVMTI_JLOCATION_JVMBCI;
 847   return JVMTI_ERROR_NONE;
 848 } /* end GetJLocationFormat */
 849 
 850   //
 851   // Thread functions
 852   //
 853 
 854 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
 855 // thread_state_ptr - pre-checked for null
 856 jvmtiError
 857 JvmtiEnv::GetThreadState(jthread thread, jint* thread_state_ptr) {
 858   JavaThread* current_thread = JavaThread::current();
 859   JvmtiVTMSTransitionDisabler disabler(thread);
 860   ThreadsListHandle tlh(current_thread);
 861 
 862   JavaThread* java_thread = nullptr;
 863   oop thread_oop = nullptr;
 864   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
 865   if (err != JVMTI_ERROR_NONE && err != JVMTI_ERROR_THREAD_NOT_ALIVE) {
 866     // We got an error code so we don't have a JavaThread*, but only
 867     // return an error from here if the error is not because the thread
 868     // is a virtual thread.
 869     return err;
 870   }
 871 
 872   if (java_lang_VirtualThread::is_instance(thread_oop)) {
 873     *thread_state_ptr = JvmtiEnvBase::get_vthread_state(thread_oop, java_thread);
 874   } else {
 875     *thread_state_ptr = JvmtiEnvBase::get_thread_state(thread_oop, java_thread);
 876   }
 877   return JVMTI_ERROR_NONE;
 878 } /* end GetThreadState */
 879 
 880 
 881 // thread_ptr - pre-checked for null
 882 jvmtiError
 883 JvmtiEnv::GetCurrentThread(jthread* thread_ptr) {
 884   JavaThread* cur_thread = JavaThread::current();
 885   oop thread_oop = get_vthread_or_thread_oop(cur_thread);
 886 
 887   *thread_ptr = (jthread)JNIHandles::make_local(cur_thread, thread_oop);
 888   return JVMTI_ERROR_NONE;
 889 } /* end GetCurrentThread */
 890 
 891 
 892 // threads_count_ptr - pre-checked for null
 893 // threads_ptr - pre-checked for null
 894 jvmtiError
 895 JvmtiEnv::GetAllThreads(jint* threads_count_ptr, jthread** threads_ptr) {
 896   int nthreads        = 0;
 897   Handle *thread_objs = nullptr;
 898   Thread* current_thread = Thread::current();
 899   ResourceMark rm(current_thread);
 900   HandleMark hm(current_thread);
 901 
 902   // enumerate threads (including agent threads)
 903   ThreadsListEnumerator tle(current_thread, true);
 904   nthreads = tle.num_threads();
 905   *threads_count_ptr = nthreads;
 906 
 907   if (nthreads == 0) {
 908     *threads_ptr = nullptr;
 909     return JVMTI_ERROR_NONE;
 910   }
 911 
 912   thread_objs = NEW_RESOURCE_ARRAY(Handle, nthreads);
 913   NULL_CHECK(thread_objs, JVMTI_ERROR_OUT_OF_MEMORY);
 914 
 915   for (int i = 0; i < nthreads; i++) {
 916     thread_objs[i] = Handle(tle.get_threadObj(i));
 917   }
 918 
 919   jthread *jthreads  = new_jthreadArray(nthreads, thread_objs);
 920   NULL_CHECK(jthreads, JVMTI_ERROR_OUT_OF_MEMORY);
 921 
 922   *threads_ptr = jthreads;
 923   return JVMTI_ERROR_NONE;
 924 } /* end GetAllThreads */
 925 
 926 
 927 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
 928 jvmtiError
 929 JvmtiEnv::SuspendThread(jthread thread) {
 930   JavaThread* current = JavaThread::current();
 931   HandleMark hm(current);
 932   Handle self_tobj;
 933 
 934   jvmtiError err;
 935   {
 936     JvmtiVTMSTransitionDisabler disabler(true);
 937     ThreadsListHandle tlh(current);
 938     JavaThread* java_thread = nullptr;
 939     oop thread_oop = nullptr;
 940 
 941     err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
 942     if (err != JVMTI_ERROR_NONE) {
 943       return err;
 944     }
 945 
 946     // Do not use JvmtiVTMSTransitionDisabler in context of self suspend to avoid deadlocks.
 947     if (java_thread != current) {
 948       err = suspend_thread(thread_oop, java_thread, /* single_suspend */ true, nullptr);
 949       return err;
 950     }
 951     // protect thread_oop as a safepoint can be reached in disabler destructor
 952     self_tobj = Handle(current, thread_oop);
 953   }
 954   // Do self suspend for current JavaThread.
 955   err = suspend_thread(self_tobj(), current, /* single_suspend */ true, nullptr);
 956   return err;
 957 } /* end SuspendThread */
 958 
 959 
 960 // request_count - pre-checked to be greater than or equal to 0
 961 // request_list - pre-checked for null
 962 // results - pre-checked for null
 963 jvmtiError
 964 JvmtiEnv::SuspendThreadList(jint request_count, const jthread* request_list, jvmtiError* results) {
 965   JavaThread* current = JavaThread::current();
 966   HandleMark hm(current);
 967   Handle self_tobj;
 968   int self_idx = -1;
 969 
 970   {
 971     JvmtiVTMSTransitionDisabler disabler(true);
 972     ThreadsListHandle tlh(current);
 973 
 974     for (int i = 0; i < request_count; i++) {
 975       JavaThread *java_thread = nullptr;
 976       oop thread_oop = nullptr;
 977       jthread thread = request_list[i];
 978       jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
 979 
 980       if (thread_oop != nullptr &&
 981           java_lang_VirtualThread::is_instance(thread_oop) &&
 982           !JvmtiEnvBase::is_vthread_alive(thread_oop)) {
 983         err = JVMTI_ERROR_THREAD_NOT_ALIVE;
 984       }
 985       if (err != JVMTI_ERROR_NONE) {
 986         if (thread_oop == nullptr || err != JVMTI_ERROR_INVALID_THREAD) {
 987           results[i] = err;
 988           continue;
 989         }
 990       }
 991       if (java_thread == current) {
 992         self_idx = i;
 993         self_tobj = Handle(current, thread_oop);
 994         continue; // self suspend after all other suspends
 995       }
 996       results[i] = suspend_thread(thread_oop, java_thread, /* single_suspend */ true, nullptr);
 997     }
 998   }
 999   // Self suspend after all other suspends if necessary.
1000   // Do not use JvmtiVTMSTransitionDisabler in context of self suspend to avoid deadlocks.
1001   if (self_tobj() != nullptr) {
1002     // there should not be any error for current java_thread
1003     results[self_idx] = suspend_thread(self_tobj(), current, /* single_suspend */ true, nullptr);
1004   }
1005   // per-thread suspend results returned via results parameter
1006   return JVMTI_ERROR_NONE;
1007 } /* end SuspendThreadList */
1008 
1009 
1010 jvmtiError
1011 JvmtiEnv::SuspendAllVirtualThreads(jint except_count, const jthread* except_list) {
1012   if (!JvmtiExport::can_support_virtual_threads()) {
1013     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
1014   }
1015   JavaThread* current = JavaThread::current();
1016   HandleMark hm(current);
1017   Handle self_tobj;
1018 
1019   {
1020     ResourceMark rm(current);
1021     JvmtiVTMSTransitionDisabler disabler(true);
1022     ThreadsListHandle tlh(current);
1023     GrowableArray<jthread>* elist = new GrowableArray<jthread>(except_count);
1024 
1025     jvmtiError err = JvmtiEnvBase::check_thread_list(except_count, except_list);
1026     if (err != JVMTI_ERROR_NONE) {
1027       return err;
1028     }
1029 
1030     // Collect threads from except_list for which resumed status must be restored (only for VirtualThread case)
1031     for (int idx = 0; idx < except_count; idx++) {
1032       jthread thread = except_list[idx];
1033       oop thread_oop = JNIHandles::resolve_external_guard(thread);
1034       if (java_lang_VirtualThread::is_instance(thread_oop) && !JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1035           // is not suspended, so its resumed status must be restored
1036           elist->append(except_list[idx]);
1037       }
1038     }
1039 
1040     for (JavaThreadIteratorWithHandle jtiwh; JavaThread *java_thread = jtiwh.next(); ) {
1041       oop vt_oop = java_thread->jvmti_vthread();
1042       if (!java_thread->is_exiting() &&
1043           !java_thread->is_jvmti_agent_thread() &&
1044           !java_thread->is_hidden_from_external_view() &&
1045           vt_oop != nullptr &&
1046           ((java_lang_VirtualThread::is_instance(vt_oop) &&
1047             JvmtiEnvBase::is_vthread_alive(vt_oop) &&
1048             !JvmtiVTSuspender::is_vthread_suspended(vt_oop)) ||
1049             (vt_oop->is_a(vmClasses::BoundVirtualThread_klass()) && !java_thread->is_suspended())) &&
1050           !is_in_thread_list(except_count, except_list, vt_oop)
1051          ) {
1052         if (java_thread == current) {
1053           self_tobj = Handle(current, vt_oop);
1054           continue; // self suspend after all other suspends
1055         }
1056         suspend_thread(vt_oop, java_thread, /* single_suspend */ false, nullptr);
1057       }
1058     }
1059     JvmtiVTSuspender::register_all_vthreads_suspend();
1060 
1061     // Restore resumed state for threads from except list that were not suspended before.
1062     for (int idx = 0; idx < elist->length(); idx++) {
1063       jthread thread = elist->at(idx);
1064       oop thread_oop = JNIHandles::resolve_external_guard(thread);
1065       if (JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1066         JvmtiVTSuspender::register_vthread_resume(thread_oop);
1067       }
1068     }
1069   }
1070   // Self suspend after all other suspends if necessary.
1071   // Do not use JvmtiVTMSTransitionDisabler in context of self suspend to avoid deadlocks.
1072   if (self_tobj() != nullptr) {
1073     suspend_thread(self_tobj(), current, /* single_suspend */ false, nullptr);
1074   }
1075   return JVMTI_ERROR_NONE;
1076 } /* end SuspendAllVirtualThreads */
1077 
1078 
1079 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1080 jvmtiError
1081 JvmtiEnv::ResumeThread(jthread thread) {
1082   JvmtiVTMSTransitionDisabler disabler(true);
1083   ThreadsListHandle tlh;
1084 
1085   JavaThread* java_thread = nullptr;
1086   oop thread_oop = nullptr;
1087   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1088   if (err != JVMTI_ERROR_NONE) {
1089     return err;
1090   }
1091   err = resume_thread(thread_oop, java_thread, /* single_resume */ true);
1092   return err;
1093 } /* end ResumeThread */
1094 
1095 
1096 // request_count - pre-checked to be greater than or equal to 0
1097 // request_list - pre-checked for null
1098 // results - pre-checked for null
1099 jvmtiError
1100 JvmtiEnv::ResumeThreadList(jint request_count, const jthread* request_list, jvmtiError* results) {
1101   oop thread_oop = nullptr;
1102   JavaThread* java_thread = nullptr;
1103   JvmtiVTMSTransitionDisabler disabler(true);
1104   ThreadsListHandle tlh;
1105 
1106   for (int i = 0; i < request_count; i++) {
1107     jthread thread = request_list[i];
1108     jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1109 
1110     if (thread_oop != nullptr &&
1111         java_lang_VirtualThread::is_instance(thread_oop) &&
1112         !JvmtiEnvBase::is_vthread_alive(thread_oop)) {
1113       err = JVMTI_ERROR_THREAD_NOT_ALIVE;
1114     }
1115     if (err != JVMTI_ERROR_NONE) {
1116       if (thread_oop == nullptr || err != JVMTI_ERROR_INVALID_THREAD) {
1117         results[i] = err;
1118         continue;
1119       }
1120     }
1121     results[i] = resume_thread(thread_oop, java_thread, /* single_resume */ true);
1122   }
1123   // per-thread resume results returned via results parameter
1124   return JVMTI_ERROR_NONE;
1125 } /* end ResumeThreadList */
1126 
1127 
1128 jvmtiError
1129 JvmtiEnv::ResumeAllVirtualThreads(jint except_count, const jthread* except_list) {
1130   if (!JvmtiExport::can_support_virtual_threads()) {
1131     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
1132   }
1133   jvmtiError err = JvmtiEnvBase::check_thread_list(except_count, except_list);
1134   if (err != JVMTI_ERROR_NONE) {
1135     return err;
1136   }
1137   ResourceMark rm;
1138   JvmtiVTMSTransitionDisabler disabler(true);
1139   GrowableArray<jthread>* elist = new GrowableArray<jthread>(except_count);
1140 
1141   // Collect threads from except_list for which suspended status must be restored (only for VirtualThread case)
1142   for (int idx = 0; idx < except_count; idx++) {
1143     jthread thread = except_list[idx];
1144     oop thread_oop = JNIHandles::resolve_external_guard(thread);
1145     if (java_lang_VirtualThread::is_instance(thread_oop) && JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1146       // is suspended, so its suspended status must be restored
1147       elist->append(except_list[idx]);
1148     }
1149   }
1150 
1151   for (JavaThreadIteratorWithHandle jtiwh; JavaThread *java_thread = jtiwh.next(); ) {
1152     oop vt_oop = java_thread->jvmti_vthread();
1153     if (!java_thread->is_exiting() &&
1154         !java_thread->is_jvmti_agent_thread() &&
1155         !java_thread->is_hidden_from_external_view() &&
1156         vt_oop != nullptr &&
1157         ((java_lang_VirtualThread::is_instance(vt_oop) &&
1158           JvmtiEnvBase::is_vthread_alive(vt_oop) &&
1159           JvmtiVTSuspender::is_vthread_suspended(vt_oop)) ||
1160           (vt_oop->is_a(vmClasses::BoundVirtualThread_klass()) && java_thread->is_suspended())) &&
1161         !is_in_thread_list(except_count, except_list, vt_oop)
1162     ) {
1163       resume_thread(vt_oop, java_thread, /* single_resume */ false);
1164     }
1165   }
1166   JvmtiVTSuspender::register_all_vthreads_resume();
1167 
1168   // Restore suspended state for threads from except list that were suspended before.
1169   for (int idx = 0; idx < elist->length(); idx++) {
1170     jthread thread = elist->at(idx);
1171     oop thread_oop = JNIHandles::resolve_external_guard(thread);
1172     if (!JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1173       JvmtiVTSuspender::register_vthread_suspend(thread_oop);
1174     }
1175   }
1176   return JVMTI_ERROR_NONE;
1177 } /* end ResumeAllVirtualThreads */
1178 
1179 
1180 jvmtiError
1181 JvmtiEnv::StopThread(jthread thread, jobject exception) {
1182   JavaThread* current_thread = JavaThread::current();
1183 
1184   JvmtiVTMSTransitionDisabler disabler(thread);
1185   ThreadsListHandle tlh(current_thread);
1186   JavaThread* java_thread = nullptr;
1187   oop thread_oop = nullptr;
1188 
1189   NULL_CHECK(thread, JVMTI_ERROR_INVALID_THREAD);
1190 
1191   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1192 
1193   bool is_virtual = thread_oop != nullptr && thread_oop->is_a(vmClasses::BaseVirtualThread_klass());
1194 
1195   if (is_virtual && !is_JavaThread_current(java_thread, thread_oop)) {
1196     if (!is_vthread_suspended(thread_oop, java_thread)) {
1197       return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
1198     }
1199     if (java_thread == nullptr) { // unmounted virtual thread
1200       return JVMTI_ERROR_OPAQUE_FRAME;
1201     }
1202   }
1203   if (err != JVMTI_ERROR_NONE) {
1204     return err;
1205   }
1206   oop e = JNIHandles::resolve_external_guard(exception);
1207   NULL_CHECK(e, JVMTI_ERROR_NULL_POINTER);
1208 
1209   JavaThread::send_async_exception(java_thread, e);
1210 
1211   return JVMTI_ERROR_NONE;
1212 
1213 } /* end StopThread */
1214 
1215 
1216 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1217 jvmtiError
1218 JvmtiEnv::InterruptThread(jthread thread) {
1219   JavaThread* current_thread  = JavaThread::current();
1220   HandleMark hm(current_thread);
1221 
1222   JvmtiVTMSTransitionDisabler disabler(thread);
1223   ThreadsListHandle tlh(current_thread);
1224 
1225   JavaThread* java_thread = nullptr;
1226   oop thread_obj = nullptr;
1227   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
1228   if (err != JVMTI_ERROR_NONE) {
1229     return err;
1230   }
1231 
1232   if (java_lang_VirtualThread::is_instance(thread_obj)) {
1233     // For virtual threads we have to call into Java to interrupt:
1234     Handle obj(current_thread, thread_obj);
1235     JavaValue result(T_VOID);
1236     JavaCalls::call_virtual(&result,
1237                             obj,
1238                             vmClasses::Thread_klass(),
1239                             vmSymbols::interrupt_method_name(),
1240                             vmSymbols::void_method_signature(),
1241                             current_thread);
1242 
1243     return JVMTI_ERROR_NONE;
1244   }
1245 
1246   // Really this should be a Java call to Thread.interrupt to ensure the same
1247   // semantics, however historically this has not been done for some reason.
1248   // So we continue with that (which means we don't interact with any Java-level
1249   // Interruptible object) but we must set the Java-level interrupted state.
1250   java_lang_Thread::set_interrupted(thread_obj, true);
1251   java_thread->interrupt();
1252 
1253   return JVMTI_ERROR_NONE;
1254 } /* end InterruptThread */
1255 
1256 
1257 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1258 // info_ptr - pre-checked for null
1259 jvmtiError
1260 JvmtiEnv::GetThreadInfo(jthread thread, jvmtiThreadInfo* info_ptr) {
1261   JavaThread* current_thread = JavaThread::current();
1262   ResourceMark rm(current_thread);
1263   HandleMark hm(current_thread);
1264   JavaThread* java_thread = nullptr;
1265   oop thread_oop = nullptr;
1266 
1267   JvmtiVTMSTransitionDisabler disabler(thread);
1268   ThreadsListHandle tlh(current_thread);
1269 
1270   // if thread is null the current thread is used
1271   if (thread == nullptr) {
1272     java_thread = JavaThread::current();
1273     thread_oop = get_vthread_or_thread_oop(java_thread);
1274     if (thread_oop == nullptr || !thread_oop->is_a(vmClasses::Thread_klass())) {
1275       return JVMTI_ERROR_INVALID_THREAD;
1276     }
1277   } else {
1278     jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1279     if (err != JVMTI_ERROR_NONE) {
1280       // We got an error code so we don't have a JavaThread *, but
1281       // only return an error from here if we didn't get a valid
1282       // thread_oop.
1283       // In the virtual thread case the cv_external_thread_to_JavaThread is expected to correctly set
1284       // the thread_oop and return JVMTI_ERROR_INVALID_THREAD which we ignore here.
1285       if (thread_oop == nullptr) {
1286         return err;
1287       }
1288     }
1289   }
1290   // We have a valid thread_oop so we can return some thread info.
1291 
1292   Handle thread_obj(current_thread, thread_oop);
1293   Handle name;
1294   ThreadPriority priority;
1295   Handle     thread_group;
1296   Handle context_class_loader;
1297   bool          is_daemon;
1298 
1299   name = Handle(current_thread, java_lang_Thread::name(thread_obj()));
1300 
1301   if (java_lang_VirtualThread::is_instance(thread_obj())) {
1302     priority = (ThreadPriority)JVMTI_THREAD_NORM_PRIORITY;
1303     is_daemon = true;
1304     if (java_lang_VirtualThread::state(thread_obj()) == java_lang_VirtualThread::TERMINATED) {
1305       thread_group = Handle(current_thread, nullptr);
1306     } else {
1307       thread_group = Handle(current_thread, java_lang_Thread_Constants::get_VTHREAD_GROUP());
1308     }
1309   } else {
1310     priority = java_lang_Thread::priority(thread_obj());
1311     is_daemon = java_lang_Thread::is_daemon(thread_obj());
1312     if (java_lang_Thread::get_thread_status(thread_obj()) == JavaThreadStatus::TERMINATED) {
1313       thread_group = Handle(current_thread, nullptr);
1314     } else {
1315       thread_group = Handle(current_thread, java_lang_Thread::threadGroup(thread_obj()));
1316     }
1317   }
1318 
1319   oop loader = java_lang_Thread::context_class_loader(thread_obj());
1320   context_class_loader = Handle(current_thread, loader);
1321 
1322   { const char *n;
1323 
1324     if (name() != nullptr) {
1325       n = java_lang_String::as_utf8_string(name());
1326     } else {
1327       int utf8_length = 0;
1328       n = UNICODE::as_utf8((jchar*) nullptr, utf8_length);
1329     }
1330 
1331     info_ptr->name = (char *) jvmtiMalloc(strlen(n)+1);
1332     if (info_ptr->name == nullptr)
1333       return JVMTI_ERROR_OUT_OF_MEMORY;
1334 
1335     strcpy(info_ptr->name, n);
1336   }
1337   info_ptr->is_daemon = is_daemon;
1338   info_ptr->priority  = priority;
1339 
1340   info_ptr->context_class_loader = (context_class_loader.is_null()) ? nullptr :
1341                                     jni_reference(context_class_loader);
1342   info_ptr->thread_group = jni_reference(thread_group);
1343 
1344   return JVMTI_ERROR_NONE;
1345 } /* end GetThreadInfo */
1346 
1347 
1348 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1349 // owned_monitor_count_ptr - pre-checked for null
1350 // owned_monitors_ptr - pre-checked for null
1351 jvmtiError
1352 JvmtiEnv::GetOwnedMonitorInfo(jthread thread, jint* owned_monitor_count_ptr, jobject** owned_monitors_ptr) {
1353   JavaThread* calling_thread = JavaThread::current();
1354   HandleMark hm(calling_thread);
1355 
1356   // growable array of jvmti monitors info on the C-heap
1357   GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list =
1358       new (mtServiceability) GrowableArray<jvmtiMonitorStackDepthInfo*>(1, mtServiceability);
1359 
1360   JvmtiVTMSTransitionDisabler disabler(thread);
1361   ThreadsListHandle tlh(calling_thread);
1362 
1363   JavaThread* java_thread = nullptr;
1364   oop thread_oop = nullptr;
1365   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1366   if (err != JVMTI_ERROR_NONE) {
1367     delete owned_monitors_list;
1368     return err;
1369   }
1370 
1371   if (java_lang_VirtualThread::is_instance(thread_oop)) {
1372     // There is no monitor info to collect if target virtual thread is unmounted.
1373     if (java_thread != nullptr) {
1374       VirtualThreadGetOwnedMonitorInfoClosure op(this,
1375                                                  Handle(calling_thread, thread_oop),
1376                                                  owned_monitors_list);
1377       Handshake::execute(&op, java_thread);
1378       err = op.result();
1379     }
1380   } else {
1381     EscapeBarrier eb(true, calling_thread, java_thread);
1382     if (!eb.deoptimize_objects(MaxJavaStackTraceDepth)) {
1383       delete owned_monitors_list;
1384       return JVMTI_ERROR_OUT_OF_MEMORY;
1385     }
1386 
1387     if (java_thread == calling_thread) {
1388       // It is only safe to make a direct call on the current thread.
1389       // All other usage needs to use a direct handshake for safety.
1390       err = get_owned_monitors(calling_thread, java_thread, owned_monitors_list);
1391     } else {
1392       // get owned monitors info with handshake
1393       GetOwnedMonitorInfoClosure op(calling_thread, this, owned_monitors_list);
1394       Handshake::execute(&op, java_thread);
1395       err = op.result();
1396     }
1397   }
1398 
1399   jint owned_monitor_count = owned_monitors_list->length();
1400   if (err == JVMTI_ERROR_NONE) {
1401     if ((err = allocate(owned_monitor_count * sizeof(jobject *),
1402                       (unsigned char**)owned_monitors_ptr)) == JVMTI_ERROR_NONE) {
1403       // copy into the returned array
1404       for (int i = 0; i < owned_monitor_count; i++) {
1405         (*owned_monitors_ptr)[i] =
1406           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->monitor;
1407       }
1408       *owned_monitor_count_ptr = owned_monitor_count;
1409     }
1410   }
1411   // clean up.
1412   for (int i = 0; i < owned_monitor_count; i++) {
1413     deallocate((unsigned char*)owned_monitors_list->at(i));
1414   }
1415   delete owned_monitors_list;
1416 
1417   return err;
1418 } /* end GetOwnedMonitorInfo */
1419 
1420 
1421 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1422 // monitor_info_count_ptr - pre-checked for null
1423 // monitor_info_ptr - pre-checked for null
1424 jvmtiError
1425 JvmtiEnv::GetOwnedMonitorStackDepthInfo(jthread thread, jint* monitor_info_count_ptr, jvmtiMonitorStackDepthInfo** monitor_info_ptr) {
1426   JavaThread* calling_thread = JavaThread::current();
1427   HandleMark hm(calling_thread);
1428 
1429   // growable array of jvmti monitors info on the C-heap
1430   GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list =
1431          new (mtServiceability) GrowableArray<jvmtiMonitorStackDepthInfo*>(1, mtServiceability);
1432 
1433   JvmtiVTMSTransitionDisabler disabler(thread);
1434   ThreadsListHandle tlh(calling_thread);
1435 
1436   JavaThread* java_thread = nullptr;
1437   oop thread_oop = nullptr;
1438   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1439   if (err != JVMTI_ERROR_NONE) {
1440     delete owned_monitors_list;
1441     return err;
1442   }
1443 
1444   if (java_lang_VirtualThread::is_instance(thread_oop)) {
1445     // There is no monitor info to collect if target virtual thread is unmounted.
1446     if (java_thread != nullptr) {
1447       VirtualThreadGetOwnedMonitorInfoClosure op(this,
1448                                                  Handle(calling_thread, thread_oop),
1449                                                  owned_monitors_list);
1450       Handshake::execute(&op, java_thread);
1451       err = op.result();
1452     }
1453   } else {
1454     EscapeBarrier eb(true, calling_thread, java_thread);
1455     if (!eb.deoptimize_objects(MaxJavaStackTraceDepth)) {
1456       delete owned_monitors_list;
1457       return JVMTI_ERROR_OUT_OF_MEMORY;
1458     }
1459 
1460     if (java_thread == calling_thread) {
1461       // It is only safe to make a direct call on the current thread.
1462       // All other usage needs to use a direct handshake for safety.
1463       err = get_owned_monitors(calling_thread, java_thread, owned_monitors_list);
1464     } else {
1465       // get owned monitors info with handshake
1466       GetOwnedMonitorInfoClosure op(calling_thread, this, owned_monitors_list);
1467       Handshake::execute(&op, java_thread);
1468       err = op.result();
1469     }
1470   }
1471   jint owned_monitor_count = owned_monitors_list->length();
1472   if (err == JVMTI_ERROR_NONE) {
1473     if ((err = allocate(owned_monitor_count * sizeof(jvmtiMonitorStackDepthInfo),
1474                         (unsigned char**)monitor_info_ptr)) == JVMTI_ERROR_NONE) {
1475       // copy to output array.
1476       for (int i = 0; i < owned_monitor_count; i++) {
1477         (*monitor_info_ptr)[i].monitor =
1478           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->monitor;
1479         (*monitor_info_ptr)[i].stack_depth =
1480           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->stack_depth;
1481       }
1482     }
1483     *monitor_info_count_ptr = owned_monitor_count;
1484   }
1485 
1486   // clean up.
1487   for (int i = 0; i < owned_monitor_count; i++) {
1488     deallocate((unsigned char*)owned_monitors_list->at(i));
1489   }
1490   delete owned_monitors_list;
1491 
1492   return err;
1493 } /* end GetOwnedMonitorStackDepthInfo */
1494 
1495 
1496 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1497 // monitor_ptr - pre-checked for null
1498 jvmtiError
1499 JvmtiEnv::GetCurrentContendedMonitor(jthread thread, jobject* monitor_ptr) {
1500   JavaThread* calling_thread = JavaThread::current();
1501   HandleMark hm(calling_thread);
1502 
1503   JvmtiVTMSTransitionDisabler disabler(thread);
1504   ThreadsListHandle tlh(calling_thread);
1505 
1506   JavaThread* java_thread = nullptr;
1507   oop thread_oop = nullptr;
1508   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1509   if (err != JVMTI_ERROR_NONE) {
1510     return err;
1511   }
1512 
1513   if (java_lang_VirtualThread::is_instance(thread_oop)) {
1514     // There is no monitor info to collect if target virtual thread is unmounted.
1515     if (java_thread != nullptr) {
1516       GetCurrentContendedMonitorClosure op(calling_thread, this, monitor_ptr, /* is_virtual */ true);
1517       Handshake::execute(&op, java_thread);
1518       err = op.result();
1519     } else {
1520       *monitor_ptr = nullptr;
1521       if (!JvmtiEnvBase::is_vthread_alive(thread_oop)) {
1522         err = JVMTI_ERROR_THREAD_NOT_ALIVE;
1523       }
1524     }
1525     return err;
1526   }
1527   if (java_thread == calling_thread) {
1528     // It is only safe to make a direct call on the current thread.
1529     // All other usage needs to use a direct handshake for safety.
1530     err = get_current_contended_monitor(calling_thread, java_thread, monitor_ptr, /* is_virtual */ false);
1531   } else {
1532     // get contended monitor information with handshake
1533     GetCurrentContendedMonitorClosure op(calling_thread, this, monitor_ptr, /* is_virtual */ false);
1534     Handshake::execute(&op, java_thread);
1535     err = op.result();
1536   }
1537   return err;
1538 } /* end GetCurrentContendedMonitor */
1539 
1540 
1541 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1542 // proc - pre-checked for null
1543 // arg - null is a valid value, must be checked
1544 jvmtiError
1545 JvmtiEnv::RunAgentThread(jthread thread, jvmtiStartFunction proc, const void* arg, jint priority) {
1546   JavaThread* current_thread = JavaThread::current();
1547 
1548   JavaThread* java_thread = nullptr;
1549   oop thread_oop = nullptr;
1550   ThreadsListHandle tlh(current_thread);
1551   jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1552   if (err != JVMTI_ERROR_NONE) {
1553     // We got an error code so we don't have a JavaThread *, but
1554     // only return an error from here if we didn't get a valid
1555     // thread_oop.
1556     if (thread_oop == nullptr) {
1557       return err;
1558     }
1559     // We have a valid thread_oop.
1560   }
1561 
1562   if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
1563     // No support for virtual threads.
1564     return JVMTI_ERROR_UNSUPPORTED_OPERATION;
1565   }
1566   if (java_thread != nullptr) {
1567     // 'thread' refers to an existing JavaThread.
1568     return JVMTI_ERROR_INVALID_THREAD;
1569   }
1570 
1571   if (priority < JVMTI_THREAD_MIN_PRIORITY || priority > JVMTI_THREAD_MAX_PRIORITY) {
1572     return JVMTI_ERROR_INVALID_PRIORITY;
1573   }
1574 
1575   Handle thread_hndl(current_thread, thread_oop);
1576 
1577   JvmtiAgentThread* new_thread = new JvmtiAgentThread(this, proc, arg);
1578 
1579   // At this point it may be possible that no osthread was created for the
1580   // JavaThread due to lack of resources.
1581   if (new_thread->osthread() == nullptr) {
1582     // The new thread is not known to Thread-SMR yet so we can just delete.
1583     delete new_thread;
1584     return JVMTI_ERROR_OUT_OF_MEMORY;
1585   }
1586 
1587   JavaThread::start_internal_daemon(current_thread, new_thread, thread_hndl,
1588                                     (ThreadPriority)priority);
1589 
1590   return JVMTI_ERROR_NONE;
1591 } /* end RunAgentThread */
1592 
1593   //
1594   // Thread Group functions
1595   //
1596 
1597 // group_count_ptr - pre-checked for null
1598 // groups_ptr - pre-checked for null
1599 jvmtiError
1600 JvmtiEnv::GetTopThreadGroups(jint* group_count_ptr, jthreadGroup** groups_ptr) {
1601   JavaThread* current_thread = JavaThread::current();
1602 
1603   // Only one top level thread group now.
1604   *group_count_ptr = 1;
1605 
1606   // Allocate memory to store global-refs to the thread groups.
1607   // Assume this area is freed by caller.
1608   *groups_ptr = (jthreadGroup *) jvmtiMalloc((sizeof(jthreadGroup)) * (*group_count_ptr));
1609 
1610   NULL_CHECK(*groups_ptr, JVMTI_ERROR_OUT_OF_MEMORY);
1611 
1612   // Convert oop to Handle, then convert Handle to global-ref.
1613   {
1614     HandleMark hm(current_thread);
1615     Handle system_thread_group(current_thread, Universe::system_thread_group());
1616     *groups_ptr[0] = jni_reference(system_thread_group);
1617   }
1618 
1619   return JVMTI_ERROR_NONE;
1620 } /* end GetTopThreadGroups */
1621 
1622 
1623 // info_ptr - pre-checked for null
1624 jvmtiError
1625 JvmtiEnv::GetThreadGroupInfo(jthreadGroup group, jvmtiThreadGroupInfo* info_ptr) {
1626   Thread* current_thread = Thread::current();
1627   ResourceMark rm(current_thread);
1628   HandleMark hm(current_thread);
1629 
1630   Handle group_obj (current_thread, JNIHandles::resolve_external_guard(group));
1631   NULL_CHECK(group_obj(), JVMTI_ERROR_INVALID_THREAD_GROUP);
1632 
1633   const char* name;
1634   Handle parent_group;
1635   bool is_daemon;
1636   ThreadPriority max_priority;
1637 
1638   name         = java_lang_ThreadGroup::name(group_obj());
1639   parent_group = Handle(current_thread, java_lang_ThreadGroup::parent(group_obj()));
1640   is_daemon    = java_lang_ThreadGroup::is_daemon(group_obj());
1641   max_priority = java_lang_ThreadGroup::maxPriority(group_obj());
1642 
1643   info_ptr->is_daemon    = is_daemon;
1644   info_ptr->max_priority = max_priority;
1645   info_ptr->parent       = jni_reference(parent_group);
1646 
1647   if (name != nullptr) {
1648     info_ptr->name = (char*)jvmtiMalloc(strlen(name)+1);
1649     NULL_CHECK(info_ptr->name, JVMTI_ERROR_OUT_OF_MEMORY);
1650     strcpy(info_ptr->name, name);
1651   } else {
1652     info_ptr->name = nullptr;
1653   }
1654 
1655   return JVMTI_ERROR_NONE;
1656 } /* end GetThreadGroupInfo */
1657 
1658 // thread_count_ptr - pre-checked for null
1659 // threads_ptr - pre-checked for null
1660 // group_count_ptr - pre-checked for null
1661 // groups_ptr - pre-checked for null
1662 jvmtiError
1663 JvmtiEnv::GetThreadGroupChildren(jthreadGroup group, jint* thread_count_ptr, jthread** threads_ptr, jint* group_count_ptr, jthreadGroup** groups_ptr) {
1664   jvmtiError err;
1665   JavaThread* current_thread = JavaThread::current();
1666   oop group_obj = JNIHandles::resolve_external_guard(group);
1667   NULL_CHECK(group_obj, JVMTI_ERROR_INVALID_THREAD_GROUP);
1668 
1669   Handle *thread_objs = nullptr;
1670   objArrayHandle group_objs;
1671   jint nthreads = 0;
1672   jint ngroups = 0;
1673   int hidden_threads = 0;
1674 
1675   ResourceMark rm(current_thread);
1676   HandleMark hm(current_thread);
1677 
1678   Handle group_hdl(current_thread, group_obj);
1679 
1680   err = get_live_threads(current_thread, group_hdl, &nthreads, &thread_objs);
1681   if (err != JVMTI_ERROR_NONE) {
1682     return err;
1683   }
1684   err = get_subgroups(current_thread, group_hdl, &ngroups, &group_objs);
1685   if (err != JVMTI_ERROR_NONE) {
1686     return err;
1687   }
1688 
1689   *group_count_ptr  = ngroups;
1690   *thread_count_ptr = nthreads;
1691   *threads_ptr     = new_jthreadArray(nthreads, thread_objs);
1692   *groups_ptr      = new_jthreadGroupArray(ngroups, group_objs);
1693   if (nthreads > 0 && *threads_ptr == nullptr) {
1694     return JVMTI_ERROR_OUT_OF_MEMORY;
1695   }
1696   if (ngroups > 0 && *groups_ptr == nullptr) {
1697     return JVMTI_ERROR_OUT_OF_MEMORY;
1698   }
1699 
1700   return JVMTI_ERROR_NONE;
1701 } /* end GetThreadGroupChildren */
1702 
1703 
1704   //
1705   // Stack Frame functions
1706   //
1707 
1708 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1709 // max_frame_count - pre-checked to be greater than or equal to 0
1710 // frame_buffer - pre-checked for null
1711 // count_ptr - pre-checked for null
1712 jvmtiError
1713 JvmtiEnv::GetStackTrace(jthread thread, jint start_depth, jint max_frame_count, jvmtiFrameInfo* frame_buffer, jint* count_ptr) {
1714   JavaThread* current_thread = JavaThread::current();
1715   HandleMark hm(current_thread);
1716 
1717   JvmtiVTMSTransitionDisabler disabler(thread);
1718   ThreadsListHandle tlh(current_thread);
1719 
1720   JavaThread* java_thread = nullptr;
1721   oop thread_obj = nullptr;
1722   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
1723   if (err != JVMTI_ERROR_NONE) {
1724     return err;
1725   }
1726 
1727   if (java_lang_VirtualThread::is_instance(thread_obj)) {
1728     if (java_thread == nullptr) {  // Target virtual thread is unmounted.
1729       ResourceMark rm(current_thread);
1730 
1731       VM_VirtualThreadGetStackTrace op(this, Handle(current_thread, thread_obj),
1732                                        start_depth, max_frame_count,
1733                                        frame_buffer, count_ptr);
1734       VMThread::execute(&op);
1735       return op.result();
1736     }
1737     VirtualThreadGetStackTraceClosure op(this, Handle(current_thread, thread_obj),
1738                                          start_depth, max_frame_count, frame_buffer, count_ptr);
1739     Handshake::execute(&op, java_thread);
1740     return op.result();
1741   }
1742 
1743   // It is only safe to perform the direct operation on the current
1744   // thread. All other usage needs to use a direct handshake for safety.
1745   if (java_thread == JavaThread::current()) {
1746     err = get_stack_trace(java_thread, start_depth, max_frame_count, frame_buffer, count_ptr);
1747   } else {
1748     // Get stack trace with handshake.
1749     GetStackTraceClosure op(this, start_depth, max_frame_count, frame_buffer, count_ptr);
1750     Handshake::execute(&op, java_thread);
1751     err = op.result();
1752   }
1753 
1754   return err;
1755 } /* end GetStackTrace */
1756 
1757 
1758 // max_frame_count - pre-checked to be greater than or equal to 0
1759 // stack_info_ptr - pre-checked for null
1760 // thread_count_ptr - pre-checked for null
1761 jvmtiError
1762 JvmtiEnv::GetAllStackTraces(jint max_frame_count, jvmtiStackInfo** stack_info_ptr, jint* thread_count_ptr) {
1763   jvmtiError err = JVMTI_ERROR_NONE;
1764   JavaThread* calling_thread = JavaThread::current();
1765 
1766   // JVMTI get stack traces at safepoint.
1767   VM_GetAllStackTraces op(this, calling_thread, max_frame_count);
1768   VMThread::execute(&op);
1769   *thread_count_ptr = op.final_thread_count();
1770   *stack_info_ptr = op.stack_info();
1771   err = op.result();
1772   return err;
1773 } /* end GetAllStackTraces */
1774 
1775 
1776 // thread_count - pre-checked to be greater than or equal to 0
1777 // thread_list - pre-checked for null
1778 // max_frame_count - pre-checked to be greater than or equal to 0
1779 // stack_info_ptr - pre-checked for null
1780 jvmtiError
1781 JvmtiEnv::GetThreadListStackTraces(jint thread_count, const jthread* thread_list, jint max_frame_count, jvmtiStackInfo** stack_info_ptr) {
1782   jvmtiError err = JVMTI_ERROR_NONE;
1783   JvmtiVTMSTransitionDisabler disabler;
1784 
1785   if (thread_count == 1) {
1786 
1787     // Use direct handshake if we need to get only one stack trace.
1788     JavaThread *current_thread = JavaThread::current();
1789     ThreadsListHandle tlh(current_thread);
1790 
1791     jthread thread = thread_list[0];
1792     JavaThread *java_thread;
1793     oop thread_obj = nullptr;
1794     err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
1795     if (err != JVMTI_ERROR_NONE) {
1796       return err;
1797     }
1798 
1799     if (java_lang_VirtualThread::is_instance(thread_obj) && java_thread == nullptr) {
1800       // Target virtual thread is unmounted.
1801       ResourceMark rm(current_thread);
1802       MultipleStackTracesCollector collector(this, max_frame_count);
1803       collector.fill_frames(thread, java_thread, thread_obj);
1804       collector.allocate_and_fill_stacks(/* thread_count */ 1);
1805       *stack_info_ptr = collector.stack_info();
1806       return collector.result();
1807     }
1808 
1809     GetSingleStackTraceClosure op(this, current_thread, thread, max_frame_count);
1810     Handshake::execute(&op, &tlh, java_thread);
1811     err = op.result();
1812     if (err == JVMTI_ERROR_NONE) {
1813       *stack_info_ptr = op.stack_info();
1814     }
1815   } else {
1816     // JVMTI get stack traces at safepoint.
1817     VM_GetThreadListStackTraces op(this, thread_count, thread_list, max_frame_count);
1818     VMThread::execute(&op);
1819     err = op.result();
1820     if (err == JVMTI_ERROR_NONE) {
1821       *stack_info_ptr = op.stack_info();
1822     }
1823   }
1824   return err;
1825 } /* end GetThreadListStackTraces */
1826 
1827 
1828 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1829 // count_ptr - pre-checked for null
1830 jvmtiError
1831 JvmtiEnv::GetFrameCount(jthread thread, jint* count_ptr) {
1832   JavaThread* current_thread = JavaThread::current();
1833   HandleMark hm(current_thread);
1834 
1835   JvmtiVTMSTransitionDisabler disabler(thread);
1836   ThreadsListHandle tlh(current_thread);
1837 
1838   JavaThread* java_thread = nullptr;
1839   oop thread_obj = nullptr;
1840   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
1841   if (err != JVMTI_ERROR_NONE) {
1842     return err;
1843   }
1844 
1845   if (java_lang_VirtualThread::is_instance(thread_obj)) {
1846     if (java_thread == nullptr) {  // Target virtual thread is unmounted.
1847       VM_VirtualThreadGetFrameCount op(this, Handle(current_thread, thread_obj),  count_ptr);
1848       VMThread::execute(&op);
1849       return op.result();
1850     }
1851     VirtualThreadGetFrameCountClosure op(this, Handle(current_thread, thread_obj), count_ptr);
1852     Handshake::execute(&op, java_thread);
1853     return op.result();
1854   }
1855 
1856   // It is only safe to perform the direct operation on the current
1857   // thread. All other usage needs to use a direct handshake for safety.
1858   if (java_thread == JavaThread::current()) {
1859     err = get_frame_count(java_thread, count_ptr);
1860   } else {
1861     // get java stack frame count with handshake.
1862     GetFrameCountClosure op(this, count_ptr);
1863     Handshake::execute(&op, java_thread);
1864     err = op.result();
1865   }
1866   return err;
1867 } /* end GetFrameCount */
1868 
1869 
1870 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1871 jvmtiError
1872 JvmtiEnv::PopFrame(jthread thread) {
1873   JavaThread* current_thread = JavaThread::current();
1874   HandleMark hm(current_thread);
1875 
1876   if (thread == nullptr) {
1877     return JVMTI_ERROR_INVALID_THREAD;
1878   }
1879   JvmtiVTMSTransitionDisabler disabler(thread);
1880   ThreadsListHandle tlh(current_thread);
1881 
1882   JavaThread* java_thread = nullptr;
1883   oop thread_obj = nullptr;
1884   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
1885 
1886   if (err != JVMTI_ERROR_NONE) {
1887     return err;
1888   }
1889   bool self = java_thread == current_thread;
1890 
1891   err = check_non_suspended_or_opaque_frame(java_thread, thread_obj, self);
1892   if (err != JVMTI_ERROR_NONE) {
1893     return err;
1894   }
1895 
1896   // retrieve or create the state
1897   JvmtiThreadState* state = JvmtiThreadState::state_for(java_thread);
1898   if (state == nullptr) {
1899     return JVMTI_ERROR_THREAD_NOT_ALIVE;
1900   }
1901 
1902   // Eagerly reallocate scalar replaced objects.
1903   EscapeBarrier eb(true, current_thread, java_thread);
1904   if (!eb.deoptimize_objects(1)) {
1905     // Reallocation of scalar replaced objects failed -> return with error
1906     return JVMTI_ERROR_OUT_OF_MEMORY;
1907   }
1908 
1909   MutexLocker mu(JvmtiThreadState_lock);
1910   UpdateForPopTopFrameClosure op(state);
1911   if (self) {
1912     op.doit(java_thread, self);
1913   } else {
1914     Handshake::execute(&op, java_thread);
1915   }
1916   return op.result();
1917 } /* end PopFrame */
1918 
1919 
1920 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1921 // depth - pre-checked as non-negative
1922 // method_ptr - pre-checked for null
1923 // location_ptr - pre-checked for null
1924 jvmtiError
1925 JvmtiEnv::GetFrameLocation(jthread thread, jint depth, jmethodID* method_ptr, jlocation* location_ptr) {
1926   JavaThread* current_thread = JavaThread::current();
1927   HandleMark hm(current_thread);
1928 
1929   JvmtiVTMSTransitionDisabler disabler(thread);
1930   ThreadsListHandle tlh(current_thread);
1931 
1932   JavaThread* java_thread = nullptr;
1933   oop thread_obj = nullptr;
1934   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
1935   if (err != JVMTI_ERROR_NONE) {
1936     return err;
1937   }
1938 
1939   if (java_lang_VirtualThread::is_instance(thread_obj)) {
1940     if (java_thread == nullptr) {  // Target virtual thread is unmounted.
1941       err = get_frame_location(thread_obj, depth, method_ptr, location_ptr);
1942       return err;
1943     }
1944     VirtualThreadGetFrameLocationClosure op(this, Handle(current_thread, thread_obj),
1945                                             depth, method_ptr, location_ptr);
1946     Handshake::execute(&op, java_thread);
1947     return op.result();
1948   }
1949 
1950   // It is only safe to perform the direct operation on the current
1951   // thread. All other usage needs to use a direct handshake for safety.
1952   if (java_thread == JavaThread::current()) {
1953     err = get_frame_location(java_thread, depth, method_ptr, location_ptr);
1954   } else {
1955     // JVMTI get java stack frame location via direct handshake.
1956     GetFrameLocationClosure op(this, depth, method_ptr, location_ptr);
1957     Handshake::execute(&op, java_thread);
1958     err = op.result();
1959   }
1960   return err;
1961 } /* end GetFrameLocation */
1962 
1963 
1964 // Threads_lock NOT held, java_thread not protected by lock
1965 // depth - pre-checked as non-negative
1966 jvmtiError
1967 JvmtiEnv::NotifyFramePop(jthread thread, jint depth) {
1968   ResourceMark rm;
1969   JvmtiVTMSTransitionDisabler disabler(thread);
1970   ThreadsListHandle tlh;
1971 
1972   JavaThread* java_thread = nullptr;
1973   oop thread_obj = nullptr;
1974   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
1975   if (err != JVMTI_ERROR_NONE) {
1976     return err;
1977   }
1978 
1979   JavaThread* current = JavaThread::current();
1980   HandleMark hm(current);
1981   Handle thread_handle(current, thread_obj);
1982   JvmtiThreadState *state = JvmtiThreadState::state_for(java_thread, thread_handle);
1983   if (state == nullptr) {
1984     return JVMTI_ERROR_THREAD_NOT_ALIVE;
1985   }
1986 
1987   if (java_lang_VirtualThread::is_instance(thread_handle())) {
1988     VirtualThreadSetFramePopClosure op(this, thread_handle, state, depth);
1989     MutexLocker mu(current, JvmtiThreadState_lock);
1990     if (java_thread == nullptr || java_thread == current) {
1991       // Target virtual thread is unmounted or current.
1992       op.doit(java_thread, true /* self */);
1993     } else {
1994       Handshake::execute(&op, java_thread);
1995     }
1996     return op.result();
1997   }
1998 
1999   SetFramePopClosure op(this, state, depth);
2000   MutexLocker mu(current, JvmtiThreadState_lock);
2001   if (java_thread == current) {
2002     op.doit(java_thread, true /* self */);
2003   } else {
2004     Handshake::execute(&op, java_thread);
2005   }
2006   return op.result();
2007 } /* end NotifyFramePop */
2008 
2009 
2010   //
2011   // Force Early Return functions
2012   //
2013 
2014 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2015 jvmtiError
2016 JvmtiEnv::ForceEarlyReturnObject(jthread thread, jobject value) {
2017   jvalue val;
2018   val.l = value;
2019   return force_early_return(thread, val, atos);
2020 } /* end ForceEarlyReturnObject */
2021 
2022 
2023 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2024 jvmtiError
2025 JvmtiEnv::ForceEarlyReturnInt(jthread thread, jint value) {
2026   jvalue val;
2027   val.i = value;
2028   return force_early_return(thread, val, itos);
2029 } /* end ForceEarlyReturnInt */
2030 
2031 
2032 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2033 jvmtiError
2034 JvmtiEnv::ForceEarlyReturnLong(jthread thread, jlong value) {
2035   jvalue val;
2036   val.j = value;
2037   return force_early_return(thread, val, ltos);
2038 } /* end ForceEarlyReturnLong */
2039 
2040 
2041 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2042 jvmtiError
2043 JvmtiEnv::ForceEarlyReturnFloat(jthread thread, jfloat value) {
2044   jvalue val;
2045   val.f = value;
2046   return force_early_return(thread, val, ftos);
2047 } /* end ForceEarlyReturnFloat */
2048 
2049 
2050 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2051 jvmtiError
2052 JvmtiEnv::ForceEarlyReturnDouble(jthread thread, jdouble value) {
2053   jvalue val;
2054   val.d = value;
2055   return force_early_return(thread, val, dtos);
2056 } /* end ForceEarlyReturnDouble */
2057 
2058 
2059 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2060 jvmtiError
2061 JvmtiEnv::ForceEarlyReturnVoid(jthread thread) {
2062   jvalue val;
2063   val.j = 0L;
2064   return force_early_return(thread, val, vtos);
2065 } /* end ForceEarlyReturnVoid */
2066 
2067 
2068   //
2069   // Heap functions
2070   //
2071 
2072 // klass - null is a valid value, must be checked
2073 // initial_object - null is a valid value, must be checked
2074 // callbacks - pre-checked for null
2075 // user_data - null is a valid value, must be checked
2076 jvmtiError
2077 JvmtiEnv::FollowReferences(jint heap_filter, jclass klass, jobject initial_object, const jvmtiHeapCallbacks* callbacks, const void* user_data) {
2078   // check klass if provided
2079   Klass* k = nullptr;
2080   if (klass != nullptr) {
2081     oop k_mirror = JNIHandles::resolve_external_guard(klass);
2082     if (k_mirror == nullptr) {
2083       return JVMTI_ERROR_INVALID_CLASS;
2084     }
2085     if (java_lang_Class::is_primitive(k_mirror)) {
2086       return JVMTI_ERROR_NONE;
2087     }
2088     k = java_lang_Class::as_Klass(k_mirror);
2089     if (klass == nullptr) {
2090       return JVMTI_ERROR_INVALID_CLASS;
2091     }
2092   }
2093 
2094   if (initial_object != nullptr) {
2095     oop init_obj = JNIHandles::resolve_external_guard(initial_object);
2096     if (init_obj == nullptr) {
2097       return JVMTI_ERROR_INVALID_OBJECT;
2098     }
2099   }
2100 
2101   Thread *thread = Thread::current();
2102   HandleMark hm(thread);
2103 
2104   TraceTime t("FollowReferences", TRACETIME_LOG(Debug, jvmti, objecttagging));
2105   JvmtiTagMap::tag_map_for(this)->follow_references(heap_filter, k, initial_object, callbacks, user_data);
2106   return JVMTI_ERROR_NONE;
2107 } /* end FollowReferences */
2108 
2109 
2110 // klass - null is a valid value, must be checked
2111 // callbacks - pre-checked for null
2112 // user_data - null is a valid value, must be checked
2113 jvmtiError
2114 JvmtiEnv::IterateThroughHeap(jint heap_filter, jclass klass, const jvmtiHeapCallbacks* callbacks, const void* user_data) {
2115   // check klass if provided
2116   Klass* k = nullptr;
2117   if (klass != nullptr) {
2118     oop k_mirror = JNIHandles::resolve_external_guard(klass);
2119     if (k_mirror == nullptr) {
2120       return JVMTI_ERROR_INVALID_CLASS;
2121     }
2122     if (java_lang_Class::is_primitive(k_mirror)) {
2123       return JVMTI_ERROR_NONE;
2124     }
2125     k = java_lang_Class::as_Klass(k_mirror);
2126     if (k == nullptr) {
2127       return JVMTI_ERROR_INVALID_CLASS;
2128     }
2129   }
2130 
2131   TraceTime t("IterateThroughHeap", TRACETIME_LOG(Debug, jvmti, objecttagging));
2132   JvmtiTagMap::tag_map_for(this)->iterate_through_heap(heap_filter, k, callbacks, user_data);
2133   return JVMTI_ERROR_NONE;
2134 } /* end IterateThroughHeap */
2135 
2136 
2137 // tag_ptr - pre-checked for null
2138 jvmtiError
2139 JvmtiEnv::GetTag(jobject object, jlong* tag_ptr) {
2140   oop o = JNIHandles::resolve_external_guard(object);
2141   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
2142   *tag_ptr = JvmtiTagMap::tag_map_for(this)->get_tag(object);
2143   return JVMTI_ERROR_NONE;
2144 } /* end GetTag */
2145 
2146 
2147 jvmtiError
2148 JvmtiEnv::SetTag(jobject object, jlong tag) {
2149   oop o = JNIHandles::resolve_external_guard(object);
2150   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
2151   JvmtiTagMap::tag_map_for(this)->set_tag(object, tag);
2152   return JVMTI_ERROR_NONE;
2153 } /* end SetTag */
2154 
2155 
2156 // tag_count - pre-checked to be greater than or equal to 0
2157 // tags - pre-checked for null
2158 // count_ptr - pre-checked for null
2159 // object_result_ptr - null is a valid value, must be checked
2160 // tag_result_ptr - null is a valid value, must be checked
2161 jvmtiError
2162 JvmtiEnv::GetObjectsWithTags(jint tag_count, const jlong* tags, jint* count_ptr, jobject** object_result_ptr, jlong** tag_result_ptr) {
2163   TraceTime t("GetObjectsWithTags", TRACETIME_LOG(Debug, jvmti, objecttagging));
2164   return JvmtiTagMap::tag_map_for(this)->get_objects_with_tags((jlong*)tags, tag_count, count_ptr, object_result_ptr, tag_result_ptr);
2165 } /* end GetObjectsWithTags */
2166 
2167 
2168 jvmtiError
2169 JvmtiEnv::ForceGarbageCollection() {
2170   Universe::heap()->collect(GCCause::_jvmti_force_gc);
2171   return JVMTI_ERROR_NONE;
2172 } /* end ForceGarbageCollection */
2173 
2174 
2175   //
2176   // Heap (1.0) functions
2177   //
2178 
2179 // object_reference_callback - pre-checked for null
2180 // user_data - null is a valid value, must be checked
2181 jvmtiError
2182 JvmtiEnv::IterateOverObjectsReachableFromObject(jobject object, jvmtiObjectReferenceCallback object_reference_callback, const void* user_data) {
2183   oop o = JNIHandles::resolve_external_guard(object);
2184   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
2185   JvmtiTagMap::tag_map_for(this)->iterate_over_objects_reachable_from_object(object, object_reference_callback, user_data);
2186   return JVMTI_ERROR_NONE;
2187 } /* end IterateOverObjectsReachableFromObject */
2188 
2189 
2190 // heap_root_callback - null is a valid value, must be checked
2191 // stack_ref_callback - null is a valid value, must be checked
2192 // object_ref_callback - null is a valid value, must be checked
2193 // user_data - null is a valid value, must be checked
2194 jvmtiError
2195 JvmtiEnv::IterateOverReachableObjects(jvmtiHeapRootCallback heap_root_callback, jvmtiStackReferenceCallback stack_ref_callback, jvmtiObjectReferenceCallback object_ref_callback, const void* user_data) {
2196   TraceTime t("IterateOverReachableObjects", TRACETIME_LOG(Debug, jvmti, objecttagging));
2197   JvmtiTagMap::tag_map_for(this)->iterate_over_reachable_objects(heap_root_callback, stack_ref_callback, object_ref_callback, user_data);
2198   return JVMTI_ERROR_NONE;
2199 } /* end IterateOverReachableObjects */
2200 
2201 
2202 // heap_object_callback - pre-checked for null
2203 // user_data - null is a valid value, must be checked
2204 jvmtiError
2205 JvmtiEnv::IterateOverHeap(jvmtiHeapObjectFilter object_filter, jvmtiHeapObjectCallback heap_object_callback, const void* user_data) {
2206   TraceTime t("IterateOverHeap", TRACETIME_LOG(Debug, jvmti, objecttagging));
2207   Thread *thread = Thread::current();
2208   HandleMark hm(thread);
2209   JvmtiTagMap::tag_map_for(this)->iterate_over_heap(object_filter, nullptr, heap_object_callback, user_data);
2210   return JVMTI_ERROR_NONE;
2211 } /* end IterateOverHeap */
2212 
2213 
2214 // k_mirror - may be primitive, this must be checked
2215 // heap_object_callback - pre-checked for null
2216 // user_data - null is a valid value, must be checked
2217 jvmtiError
2218 JvmtiEnv::IterateOverInstancesOfClass(oop k_mirror, jvmtiHeapObjectFilter object_filter, jvmtiHeapObjectCallback heap_object_callback, const void* user_data) {
2219   if (java_lang_Class::is_primitive(k_mirror)) {
2220     // DO PRIMITIVE CLASS PROCESSING
2221     return JVMTI_ERROR_NONE;
2222   }
2223   Klass* klass = java_lang_Class::as_Klass(k_mirror);
2224   if (klass == nullptr) {
2225     return JVMTI_ERROR_INVALID_CLASS;
2226   }
2227   TraceTime t("IterateOverInstancesOfClass", TRACETIME_LOG(Debug, jvmti, objecttagging));
2228   JvmtiTagMap::tag_map_for(this)->iterate_over_heap(object_filter, klass, heap_object_callback, user_data);
2229   return JVMTI_ERROR_NONE;
2230 } /* end IterateOverInstancesOfClass */
2231 
2232 
2233   //
2234   // Local Variable functions
2235   //
2236 
2237 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2238 // depth - pre-checked as non-negative
2239 // value_ptr - pre-checked for null
2240 jvmtiError
2241 JvmtiEnv::GetLocalObject(jthread thread, jint depth, jint slot, jobject* value_ptr) {
2242   JavaThread* current_thread = JavaThread::current();
2243   // rm object is created to clean up the javaVFrame created in
2244   // doit_prologue(), but after doit() is finished with it.
2245   ResourceMark rm(current_thread);
2246   HandleMark hm(current_thread);
2247   JvmtiVTMSTransitionDisabler disabler(thread);
2248   ThreadsListHandle tlh(current_thread);
2249 
2250   JavaThread* java_thread = nullptr;
2251   oop thread_obj = nullptr;
2252   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2253   if (err != JVMTI_ERROR_NONE) {
2254     return err;
2255   }
2256   bool self = is_JavaThread_current(java_thread, thread_obj);
2257 
2258   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2259     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2260                                      current_thread, depth, slot, self);
2261     VMThread::execute(&op);
2262     err = op.result();
2263     if (err == JVMTI_ERROR_NONE) {
2264       *value_ptr = op.value().l;
2265     }
2266   } else {
2267     // Support for ordinary threads
2268     VM_GetOrSetLocal op(java_thread, current_thread, depth, slot, self);
2269     VMThread::execute(&op);
2270     err = op.result();
2271     if (err == JVMTI_ERROR_NONE) {
2272       *value_ptr = op.value().l;
2273     }
2274   }
2275   return err;
2276 } /* end GetLocalObject */
2277 
2278 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2279 // depth - pre-checked as non-negative
2280 // value - pre-checked for null
2281 jvmtiError
2282 JvmtiEnv::GetLocalInstance(jthread thread, jint depth, jobject* value_ptr){
2283   JavaThread* current_thread = JavaThread::current();
2284   // rm object is created to clean up the javaVFrame created in
2285   // doit_prologue(), but after doit() is finished with it.
2286   ResourceMark rm(current_thread);
2287   HandleMark hm(current_thread);
2288   JvmtiVTMSTransitionDisabler disabler(thread);
2289   ThreadsListHandle tlh(current_thread);
2290 
2291   JavaThread* java_thread = nullptr;
2292   oop thread_obj = nullptr;
2293   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2294   if (err != JVMTI_ERROR_NONE) {
2295     return err;
2296   }
2297   bool self = is_JavaThread_current(java_thread, thread_obj);
2298 
2299   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2300     VM_VirtualThreadGetReceiver op(this, Handle(current_thread, thread_obj),
2301                                    current_thread, depth, self);
2302     VMThread::execute(&op);
2303     err = op.result();
2304     if (err == JVMTI_ERROR_NONE) {
2305       *value_ptr = op.value().l;
2306     }
2307   } else {
2308     // Support for ordinary threads
2309     VM_GetReceiver op(java_thread, current_thread, depth, self);
2310     VMThread::execute(&op);
2311     err = op.result();
2312     if (err == JVMTI_ERROR_NONE) {
2313       *value_ptr = op.value().l;
2314     }
2315   }
2316   return err;
2317 } /* end GetLocalInstance */
2318 
2319 
2320 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2321 // depth - pre-checked as non-negative
2322 // value_ptr - pre-checked for null
2323 jvmtiError
2324 JvmtiEnv::GetLocalInt(jthread thread, jint depth, jint slot, jint* value_ptr) {
2325   JavaThread* current_thread = JavaThread::current();
2326   // rm object is created to clean up the javaVFrame created in
2327   // doit_prologue(), but after doit() is finished with it.
2328   ResourceMark rm(current_thread);
2329   HandleMark hm(current_thread);
2330   JvmtiVTMSTransitionDisabler disabler(thread);
2331   ThreadsListHandle tlh(current_thread);
2332 
2333   JavaThread* java_thread = nullptr;
2334   oop thread_obj = nullptr;
2335   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2336   if (err != JVMTI_ERROR_NONE) {
2337     return err;
2338   }
2339   bool self = is_JavaThread_current(java_thread, thread_obj);
2340 
2341   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2342     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2343                                      depth, slot, T_INT, self);
2344     VMThread::execute(&op);
2345     err = op.result();
2346     if (err == JVMTI_ERROR_NONE) {
2347       *value_ptr = op.value().i;
2348     }
2349   } else {
2350     // Support for ordinary threads
2351     VM_GetOrSetLocal op(java_thread, depth, slot, T_INT, self);
2352     VMThread::execute(&op);
2353     err = op.result();
2354     if (err == JVMTI_ERROR_NONE) {
2355       *value_ptr = op.value().i;
2356     }
2357   }
2358   return err;
2359 } /* end GetLocalInt */
2360 
2361 
2362 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2363 // depth - pre-checked as non-negative
2364 // value_ptr - pre-checked for null
2365 jvmtiError
2366 JvmtiEnv::GetLocalLong(jthread thread, jint depth, jint slot, jlong* value_ptr) {
2367   JavaThread* current_thread = JavaThread::current();
2368   // rm object is created to clean up the javaVFrame created in
2369   // doit_prologue(), but after doit() is finished with it.
2370   ResourceMark rm(current_thread);
2371   HandleMark hm(current_thread);
2372   JvmtiVTMSTransitionDisabler disabler(thread);
2373   ThreadsListHandle tlh(current_thread);
2374 
2375   JavaThread* java_thread = nullptr;
2376   oop thread_obj = nullptr;
2377   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2378   if (err != JVMTI_ERROR_NONE) {
2379     return err;
2380   }
2381   bool self = is_JavaThread_current(java_thread, thread_obj);
2382 
2383   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2384     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2385                                      depth, slot, T_LONG, self);
2386     VMThread::execute(&op);
2387     err = op.result();
2388     if (err == JVMTI_ERROR_NONE) {
2389       *value_ptr = op.value().j;
2390     }
2391   } else {
2392     // Support for ordinary threads
2393     VM_GetOrSetLocal op(java_thread, depth, slot, T_LONG, self);
2394     VMThread::execute(&op);
2395     err = op.result();
2396     if (err == JVMTI_ERROR_NONE) {
2397       *value_ptr = op.value().j;
2398     }
2399   }
2400   return err;
2401 } /* end GetLocalLong */
2402 
2403 
2404 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2405 // depth - pre-checked as non-negative
2406 // value_ptr - pre-checked for null
2407 jvmtiError
2408 JvmtiEnv::GetLocalFloat(jthread thread, jint depth, jint slot, jfloat* value_ptr) {
2409   JavaThread* current_thread = JavaThread::current();
2410   // rm object is created to clean up the javaVFrame created in
2411   // doit_prologue(), but after doit() is finished with it.
2412   ResourceMark rm(current_thread);
2413   HandleMark hm(current_thread);
2414   JvmtiVTMSTransitionDisabler disabler(thread);
2415   ThreadsListHandle tlh(current_thread);
2416 
2417   JavaThread* java_thread = nullptr;
2418   oop thread_obj = nullptr;
2419   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2420   if (err != JVMTI_ERROR_NONE) {
2421     return err;
2422   }
2423   bool self = is_JavaThread_current(java_thread, thread_obj);
2424 
2425   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2426     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2427                                      depth, slot, T_FLOAT, self);
2428     VMThread::execute(&op);
2429     err = op.result();
2430     if (err == JVMTI_ERROR_NONE) {
2431       *value_ptr = op.value().f;
2432     }
2433   } else {
2434     // Support for ordinary threads
2435     VM_GetOrSetLocal op(java_thread, depth, slot, T_FLOAT, self);
2436     VMThread::execute(&op);
2437     err = op.result();
2438     if (err == JVMTI_ERROR_NONE) {
2439       *value_ptr = op.value().f;
2440     }
2441   }
2442   return err;
2443 } /* end GetLocalFloat */
2444 
2445 
2446 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2447 // depth - pre-checked as non-negative
2448 // value_ptr - pre-checked for null
2449 jvmtiError
2450 JvmtiEnv::GetLocalDouble(jthread thread, jint depth, jint slot, jdouble* value_ptr) {
2451   JavaThread* current_thread = JavaThread::current();
2452   // rm object is created to clean up the javaVFrame created in
2453   // doit_prologue(), but after doit() is finished with it.
2454   ResourceMark rm(current_thread);
2455   HandleMark hm(current_thread);
2456   JvmtiVTMSTransitionDisabler disabler(thread);
2457   ThreadsListHandle tlh(current_thread);
2458 
2459   JavaThread* java_thread = nullptr;
2460   oop thread_obj = nullptr;
2461   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2462   if (err != JVMTI_ERROR_NONE) {
2463     return err;
2464   }
2465   bool self = is_JavaThread_current(java_thread, thread_obj);
2466 
2467   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2468     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2469                                      depth, slot, T_DOUBLE, self);
2470     VMThread::execute(&op);
2471     err = op.result();
2472     if (err == JVMTI_ERROR_NONE) {
2473       *value_ptr = op.value().d;
2474     }
2475   } else {
2476     // Support for ordinary threads
2477     VM_GetOrSetLocal op(java_thread, depth, slot, T_DOUBLE, self);
2478     VMThread::execute(&op);
2479     err = op.result();
2480     if (err == JVMTI_ERROR_NONE) {
2481       *value_ptr = op.value().d;
2482     }
2483   }
2484   return err;
2485 } /* end GetLocalDouble */
2486 
2487 
2488 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2489 // depth - pre-checked as non-negative
2490 jvmtiError
2491 JvmtiEnv::SetLocalObject(jthread thread, jint depth, jint slot, jobject value) {
2492   JavaThread* current_thread = JavaThread::current();
2493   // rm object is created to clean up the javaVFrame created in
2494   // doit_prologue(), but after doit() is finished with it.
2495   ResourceMark rm(current_thread);
2496   HandleMark hm(current_thread);
2497   JvmtiVTMSTransitionDisabler disabler(thread);
2498   ThreadsListHandle tlh(current_thread);
2499 
2500   JavaThread* java_thread = nullptr;
2501   oop thread_obj = nullptr;
2502   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2503   if (err != JVMTI_ERROR_NONE) {
2504     return err;
2505   }
2506   bool self = is_JavaThread_current(java_thread, thread_obj);
2507   jvalue val;
2508   val.l = value;
2509 
2510   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2511     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2512                                      depth, slot, T_OBJECT, val, self);
2513     VMThread::execute(&op);
2514     err = op.result();
2515   } else {
2516     // Support for ordinary threads
2517     VM_GetOrSetLocal op(java_thread, depth, slot, T_OBJECT, val, self);
2518     VMThread::execute(&op);
2519     err = op.result();
2520   }
2521   return err;
2522 } /* end SetLocalObject */
2523 
2524 
2525 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2526 // depth - pre-checked as non-negative
2527 jvmtiError
2528 JvmtiEnv::SetLocalInt(jthread thread, jint depth, jint slot, jint value) {
2529   JavaThread* current_thread = JavaThread::current();
2530   // rm object is created to clean up the javaVFrame created in
2531   // doit_prologue(), but after doit() is finished with it.
2532   ResourceMark rm(current_thread);
2533   HandleMark hm(current_thread);
2534   JvmtiVTMSTransitionDisabler disabler(thread);
2535   ThreadsListHandle tlh(current_thread);
2536 
2537   JavaThread* java_thread = nullptr;
2538   oop thread_obj = nullptr;
2539   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2540   if (err != JVMTI_ERROR_NONE) {
2541     return err;
2542   }
2543   bool self = is_JavaThread_current(java_thread, thread_obj);
2544   jvalue val;
2545   val.i = value;
2546 
2547   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2548     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2549                                      depth, slot, T_INT, val, self);
2550     VMThread::execute(&op);
2551     err = op.result();
2552   } else {
2553     // Support for ordinary threads
2554     VM_GetOrSetLocal op(java_thread, depth, slot, T_INT, val, self);
2555     VMThread::execute(&op);
2556     err = op.result();
2557   }
2558   return err;
2559 } /* end SetLocalInt */
2560 
2561 
2562 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2563 // depth - pre-checked as non-negative
2564 jvmtiError
2565 JvmtiEnv::SetLocalLong(jthread thread, jint depth, jint slot, jlong value) {
2566   JavaThread* current_thread = JavaThread::current();
2567   // rm object is created to clean up the javaVFrame created in
2568   // doit_prologue(), but after doit() is finished with it.
2569   ResourceMark rm(current_thread);
2570   HandleMark hm(current_thread);
2571   JvmtiVTMSTransitionDisabler disabler(thread);
2572   ThreadsListHandle tlh(current_thread);
2573 
2574   JavaThread* java_thread = nullptr;
2575   oop thread_obj = nullptr;
2576   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2577   if (err != JVMTI_ERROR_NONE) {
2578     return err;
2579   }
2580   bool self = is_JavaThread_current(java_thread, thread_obj);
2581   jvalue val;
2582   val.j = value;
2583 
2584   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2585     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2586                                      depth, slot, T_LONG, val, self);
2587     VMThread::execute(&op);
2588     err = op.result();
2589   } else {
2590     // Support for ordinary threads
2591     VM_GetOrSetLocal op(java_thread, depth, slot, T_LONG, val, self);
2592     VMThread::execute(&op);
2593     err = op.result();
2594   }
2595   return err;
2596 } /* end SetLocalLong */
2597 
2598 
2599 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2600 // depth - pre-checked as non-negative
2601 jvmtiError
2602 JvmtiEnv::SetLocalFloat(jthread thread, jint depth, jint slot, jfloat value) {
2603   JavaThread* current_thread = JavaThread::current();
2604   // rm object is created to clean up the javaVFrame created in
2605   // doit_prologue(), but after doit() is finished with it.
2606   ResourceMark rm(current_thread);
2607   HandleMark hm(current_thread);
2608   JvmtiVTMSTransitionDisabler disabler(thread);
2609   ThreadsListHandle tlh(current_thread);
2610 
2611   JavaThread* java_thread = nullptr;
2612   oop thread_obj = nullptr;
2613   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2614   if (err != JVMTI_ERROR_NONE) {
2615     return err;
2616   }
2617   bool self = is_JavaThread_current(java_thread, thread_obj);
2618   jvalue val;
2619   val.f = value;
2620 
2621   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2622     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2623                                      depth, slot, T_FLOAT, val, self);
2624     VMThread::execute(&op);
2625     err = op.result();
2626   } else {
2627     // Support for ordinary threads
2628     VM_GetOrSetLocal op(java_thread, depth, slot, T_FLOAT, val, self);
2629     VMThread::execute(&op);
2630     err = op.result();
2631   }
2632   return err;
2633 } /* end SetLocalFloat */
2634 
2635 
2636 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2637 // depth - pre-checked as non-negative
2638 jvmtiError
2639 JvmtiEnv::SetLocalDouble(jthread thread, jint depth, jint slot, jdouble value) {
2640   JavaThread* current_thread = JavaThread::current();
2641   // rm object is created to clean up the javaVFrame created in
2642   // doit_prologue(), but after doit() is finished with it.
2643   ResourceMark rm(current_thread);
2644   HandleMark hm(current_thread);
2645   JvmtiVTMSTransitionDisabler disabler(thread);
2646   ThreadsListHandle tlh(current_thread);
2647 
2648   JavaThread* java_thread = nullptr;
2649   oop thread_obj = nullptr;
2650   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_obj);
2651   if (err != JVMTI_ERROR_NONE) {
2652     return err;
2653   }
2654   bool self = is_JavaThread_current(java_thread, thread_obj);
2655   jvalue val;
2656   val.d = value;
2657 
2658   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2659     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2660                                      depth, slot, T_DOUBLE, val, self);
2661     VMThread::execute(&op);
2662     err = op.result();
2663   } else {
2664     // Support for ordinary threads
2665     VM_GetOrSetLocal op(java_thread, depth, slot, T_DOUBLE, val, self);
2666     VMThread::execute(&op);
2667     err = op.result();
2668   }
2669   return err;
2670 } /* end SetLocalDouble */
2671 
2672 
2673   //
2674   // Breakpoint functions
2675   //
2676 
2677 // method - pre-checked for validity, but may be null meaning obsolete method
2678 jvmtiError
2679 JvmtiEnv::SetBreakpoint(Method* method, jlocation location) {
2680   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
2681   if (location < 0) {   // simple invalid location check first
2682     return JVMTI_ERROR_INVALID_LOCATION;
2683   }
2684   // verify that the breakpoint is not past the end of the method
2685   if (location >= (jlocation) method->code_size()) {
2686     return JVMTI_ERROR_INVALID_LOCATION;
2687   }
2688 
2689   ResourceMark rm;
2690   JvmtiBreakpoint bp(method, location);
2691   JvmtiBreakpoints& jvmti_breakpoints = JvmtiCurrentBreakpoints::get_jvmti_breakpoints();
2692   if (jvmti_breakpoints.set(bp) == JVMTI_ERROR_DUPLICATE)
2693     return JVMTI_ERROR_DUPLICATE;
2694 
2695   if (TraceJVMTICalls) {
2696     jvmti_breakpoints.print();
2697   }
2698 
2699   return JVMTI_ERROR_NONE;
2700 } /* end SetBreakpoint */
2701 
2702 
2703 // method - pre-checked for validity, but may be null meaning obsolete method
2704 jvmtiError
2705 JvmtiEnv::ClearBreakpoint(Method* method, jlocation location) {
2706   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
2707 
2708   if (location < 0) {   // simple invalid location check first
2709     return JVMTI_ERROR_INVALID_LOCATION;
2710   }
2711 
2712   // verify that the breakpoint is not past the end of the method
2713   if (location >= (jlocation) method->code_size()) {
2714     return JVMTI_ERROR_INVALID_LOCATION;
2715   }
2716 
2717   JvmtiBreakpoint bp(method, location);
2718 
2719   JvmtiBreakpoints& jvmti_breakpoints = JvmtiCurrentBreakpoints::get_jvmti_breakpoints();
2720   if (jvmti_breakpoints.clear(bp) == JVMTI_ERROR_NOT_FOUND)
2721     return JVMTI_ERROR_NOT_FOUND;
2722 
2723   if (TraceJVMTICalls) {
2724     jvmti_breakpoints.print();
2725   }
2726 
2727   return JVMTI_ERROR_NONE;
2728 } /* end ClearBreakpoint */
2729 
2730 
2731   //
2732   // Watched Field functions
2733   //
2734 
2735 jvmtiError
2736 JvmtiEnv::SetFieldAccessWatch(fieldDescriptor* fdesc_ptr) {
2737   // make sure we haven't set this watch before
2738   if (fdesc_ptr->is_field_access_watched()) return JVMTI_ERROR_DUPLICATE;
2739   fdesc_ptr->set_is_field_access_watched(true);
2740 
2741   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_ACCESS, true);
2742 
2743   return JVMTI_ERROR_NONE;
2744 } /* end SetFieldAccessWatch */
2745 
2746 
2747 jvmtiError
2748 JvmtiEnv::ClearFieldAccessWatch(fieldDescriptor* fdesc_ptr) {
2749   // make sure we have a watch to clear
2750   if (!fdesc_ptr->is_field_access_watched()) return JVMTI_ERROR_NOT_FOUND;
2751   fdesc_ptr->set_is_field_access_watched(false);
2752 
2753   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_ACCESS, false);
2754 
2755   return JVMTI_ERROR_NONE;
2756 } /* end ClearFieldAccessWatch */
2757 
2758 
2759 jvmtiError
2760 JvmtiEnv::SetFieldModificationWatch(fieldDescriptor* fdesc_ptr) {
2761   // make sure we haven't set this watch before
2762   if (fdesc_ptr->is_field_modification_watched()) return JVMTI_ERROR_DUPLICATE;
2763   fdesc_ptr->set_is_field_modification_watched(true);
2764 
2765   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_MODIFICATION, true);
2766 
2767   return JVMTI_ERROR_NONE;
2768 } /* end SetFieldModificationWatch */
2769 
2770 
2771 jvmtiError
2772 JvmtiEnv::ClearFieldModificationWatch(fieldDescriptor* fdesc_ptr) {
2773    // make sure we have a watch to clear
2774   if (!fdesc_ptr->is_field_modification_watched()) return JVMTI_ERROR_NOT_FOUND;
2775   fdesc_ptr->set_is_field_modification_watched(false);
2776 
2777   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_MODIFICATION, false);
2778 
2779   return JVMTI_ERROR_NONE;
2780 } /* end ClearFieldModificationWatch */
2781 
2782   //
2783   // Class functions
2784   //
2785 
2786 
2787 // k_mirror - may be primitive, this must be checked
2788 // signature_ptr - null is a valid value, must be checked
2789 // generic_ptr - null is a valid value, must be checked
2790 jvmtiError
2791 JvmtiEnv::GetClassSignature(oop k_mirror, char** signature_ptr, char** generic_ptr) {
2792   ResourceMark rm;
2793   bool isPrimitive = java_lang_Class::is_primitive(k_mirror);
2794   Klass* k = nullptr;
2795   if (!isPrimitive) {
2796     k = java_lang_Class::as_Klass(k_mirror);
2797     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2798   }
2799   if (signature_ptr != nullptr) {
2800     char* result = nullptr;
2801     if (isPrimitive) {
2802       char tchar = type2char(java_lang_Class::primitive_type(k_mirror));
2803       result = (char*) jvmtiMalloc(2);
2804       result[0] = tchar;
2805       result[1] = '\0';
2806     } else {
2807       const char* class_sig = k->signature_name();
2808       result = (char *) jvmtiMalloc(strlen(class_sig)+1);
2809       strcpy(result, class_sig);
2810     }
2811     *signature_ptr = result;
2812   }
2813   if (generic_ptr != nullptr) {
2814     *generic_ptr = nullptr;
2815     if (!isPrimitive && k->is_instance_klass()) {
2816       Symbol* soo = InstanceKlass::cast(k)->generic_signature();
2817       if (soo != nullptr) {
2818         const char *gen_sig = soo->as_C_string();
2819         if (gen_sig != nullptr) {
2820           char* gen_result;
2821           jvmtiError err = allocate(strlen(gen_sig) + 1,
2822                                     (unsigned char **)&gen_result);
2823           if (err != JVMTI_ERROR_NONE) {
2824             return err;
2825           }
2826           strcpy(gen_result, gen_sig);
2827           *generic_ptr = gen_result;
2828         }
2829       }
2830     }
2831   }
2832   return JVMTI_ERROR_NONE;
2833 } /* end GetClassSignature */
2834 
2835 
2836 // k_mirror - may be primitive, this must be checked
2837 // status_ptr - pre-checked for null
2838 jvmtiError
2839 JvmtiEnv::GetClassStatus(oop k_mirror, jint* status_ptr) {
2840   jint result = 0;
2841   if (java_lang_Class::is_primitive(k_mirror)) {
2842     result |= JVMTI_CLASS_STATUS_PRIMITIVE;
2843   } else {
2844     Klass* k = java_lang_Class::as_Klass(k_mirror);
2845     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2846     result = k->jvmti_class_status();
2847   }
2848   *status_ptr = result;
2849 
2850   return JVMTI_ERROR_NONE;
2851 } /* end GetClassStatus */
2852 
2853 
2854 // k_mirror - may be primitive, this must be checked
2855 // source_name_ptr - pre-checked for null
2856 jvmtiError
2857 JvmtiEnv::GetSourceFileName(oop k_mirror, char** source_name_ptr) {
2858   if (java_lang_Class::is_primitive(k_mirror)) {
2859      return JVMTI_ERROR_ABSENT_INFORMATION;
2860   }
2861   Klass* k_klass = java_lang_Class::as_Klass(k_mirror);
2862   NULL_CHECK(k_klass, JVMTI_ERROR_INVALID_CLASS);
2863 
2864   if (!k_klass->is_instance_klass()) {
2865     return JVMTI_ERROR_ABSENT_INFORMATION;
2866   }
2867 
2868   Symbol* sfnOop = InstanceKlass::cast(k_klass)->source_file_name();
2869   NULL_CHECK(sfnOop, JVMTI_ERROR_ABSENT_INFORMATION);
2870   {
2871     JavaThread* current_thread  = JavaThread::current();
2872     ResourceMark rm(current_thread);
2873     const char* sfncp = (const char*) sfnOop->as_C_string();
2874     *source_name_ptr = (char *) jvmtiMalloc(strlen(sfncp)+1);
2875     strcpy(*source_name_ptr, sfncp);
2876   }
2877 
2878   return JVMTI_ERROR_NONE;
2879 } /* end GetSourceFileName */
2880 
2881 
2882 // k_mirror - may be primitive, this must be checked
2883 // modifiers_ptr - pre-checked for null
2884 jvmtiError
2885 JvmtiEnv::GetClassModifiers(oop k_mirror, jint* modifiers_ptr) {
2886   JavaThread* current_thread  = JavaThread::current();
2887   jint result = 0;
2888   if (!java_lang_Class::is_primitive(k_mirror)) {
2889     Klass* k = java_lang_Class::as_Klass(k_mirror);
2890     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2891     result = k->compute_modifier_flags();
2892 
2893     // Reset the deleted  ACC_SUPER bit (deleted in compute_modifier_flags()).
2894     // if (k->is_super()) {
2895     //   result |= JVM_ACC_SUPER;
2896     // }
2897   } else {
2898     result = (JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC);
2899   }
2900   *modifiers_ptr = result;
2901 
2902   return JVMTI_ERROR_NONE;
2903 } /* end GetClassModifiers */
2904 
2905 
2906 // k_mirror - may be primitive, this must be checked
2907 // method_count_ptr - pre-checked for null
2908 // methods_ptr - pre-checked for null
2909 jvmtiError
2910 JvmtiEnv::GetClassMethods(oop k_mirror, jint* method_count_ptr, jmethodID** methods_ptr) {
2911   JavaThread* current_thread  = JavaThread::current();
2912   HandleMark hm(current_thread);
2913 
2914   if (java_lang_Class::is_primitive(k_mirror)) {
2915     *method_count_ptr = 0;
2916     *methods_ptr = (jmethodID*) jvmtiMalloc(0 * sizeof(jmethodID));
2917     return JVMTI_ERROR_NONE;
2918   }
2919   Klass* k = java_lang_Class::as_Klass(k_mirror);
2920   NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2921 
2922   // Return CLASS_NOT_PREPARED error as per JVMTI spec.
2923   if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) )) {
2924     return JVMTI_ERROR_CLASS_NOT_PREPARED;
2925   }
2926 
2927   if (!k->is_instance_klass()) {
2928     *method_count_ptr = 0;
2929     *methods_ptr = (jmethodID*) jvmtiMalloc(0 * sizeof(jmethodID));
2930     return JVMTI_ERROR_NONE;
2931   }
2932   InstanceKlass* ik = InstanceKlass::cast(k);
2933   // Allocate the result and fill it in
2934   int result_length = ik->methods()->length();
2935   jmethodID* result_list = (jmethodID*)jvmtiMalloc(result_length * sizeof(jmethodID));
2936   int index;
2937   bool jmethodids_found = true;
2938   int skipped = 0;  // skip overpass methods
2939 
2940   for (index = 0; index < result_length; index++) {
2941     Method* m = ik->methods()->at(index);
2942     // Depending on can_maintain_original_method_order capability use the original
2943     // method ordering indices stored in the class, so we can emit jmethodIDs in
2944     // the order they appeared in the class file or just copy in current order.
2945     int result_index = JvmtiExport::can_maintain_original_method_order() ? ik->method_ordering()->at(index) : index;
2946     assert(result_index >= 0 && result_index < result_length, "invalid original method index");
2947     if (m->is_overpass()) {
2948       result_list[result_index] = nullptr;
2949       skipped++;
2950       continue;
2951     }
2952     jmethodID id;
2953     if (jmethodids_found) {
2954       id = m->find_jmethod_id_or_null();
2955       if (id == nullptr) {
2956         // If we find an uninitialized value, make sure there is
2957         // enough space for all the uninitialized values we might
2958         // find.
2959         ik->ensure_space_for_methodids(index);
2960         jmethodids_found = false;
2961         id = m->jmethod_id();
2962       }
2963     } else {
2964       id = m->jmethod_id();
2965     }
2966     result_list[result_index] = id;
2967   }
2968 
2969   // Fill in return value.
2970   if (skipped > 0) {
2971     // copy results skipping null methodIDs
2972     *methods_ptr = (jmethodID*)jvmtiMalloc((result_length - skipped) * sizeof(jmethodID));
2973     *method_count_ptr = result_length - skipped;
2974     for (index = 0, skipped = 0; index < result_length; index++) {
2975       if (result_list[index] == nullptr) {
2976         skipped++;
2977       } else {
2978         (*methods_ptr)[index - skipped] = result_list[index];
2979       }
2980     }
2981     deallocate((unsigned char *)result_list);
2982   } else {
2983     *method_count_ptr = result_length;
2984     *methods_ptr = result_list;
2985   }
2986 
2987   return JVMTI_ERROR_NONE;
2988 } /* end GetClassMethods */
2989 
2990 
2991 // k_mirror - may be primitive, this must be checked
2992 // field_count_ptr - pre-checked for null
2993 // fields_ptr - pre-checked for null
2994 jvmtiError
2995 JvmtiEnv::GetClassFields(oop k_mirror, jint* field_count_ptr, jfieldID** fields_ptr) {
2996   if (java_lang_Class::is_primitive(k_mirror)) {
2997     *field_count_ptr = 0;
2998     *fields_ptr = (jfieldID*) jvmtiMalloc(0 * sizeof(jfieldID));
2999     return JVMTI_ERROR_NONE;
3000   }
3001   JavaThread* current_thread = JavaThread::current();
3002   HandleMark hm(current_thread);
3003   Klass* k = java_lang_Class::as_Klass(k_mirror);
3004   NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3005 
3006   // Return CLASS_NOT_PREPARED error as per JVMTI spec.
3007   if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) )) {
3008     return JVMTI_ERROR_CLASS_NOT_PREPARED;
3009   }
3010 
3011   if (!k->is_instance_klass()) {
3012     *field_count_ptr = 0;
3013     *fields_ptr = (jfieldID*) jvmtiMalloc(0 * sizeof(jfieldID));
3014     return JVMTI_ERROR_NONE;
3015   }
3016 
3017 
3018   InstanceKlass* ik = InstanceKlass::cast(k);
3019 
3020   int result_count = 0;
3021   // First, count the fields.
3022   FilteredFieldStream flds(ik, true, true);
3023   result_count = flds.field_count();
3024 
3025   // Allocate the result and fill it in
3026   jfieldID* result_list = (jfieldID*) jvmtiMalloc(result_count * sizeof(jfieldID));
3027   // The JVMTI spec requires fields in the order they occur in the class file,
3028   // this is the reverse order of what FieldStream hands out.
3029   int id_index = (result_count - 1);
3030 
3031   for (FilteredFieldStream src_st(ik, true, true); !src_st.eos(); src_st.next()) {
3032     result_list[id_index--] = jfieldIDWorkaround::to_jfieldID(
3033                                             ik, src_st.offset(),
3034                                             src_st.access_flags().is_static(),
3035                                             src_st.field_descriptor().is_flat());
3036   }
3037   assert(id_index == -1, "just checking");
3038   // Fill in the results
3039   *field_count_ptr = result_count;
3040   *fields_ptr = result_list;
3041 
3042   return JVMTI_ERROR_NONE;
3043 } /* end GetClassFields */
3044 
3045 
3046 // k_mirror - may be primitive, this must be checked
3047 // interface_count_ptr - pre-checked for null
3048 // interfaces_ptr - pre-checked for null
3049 jvmtiError
3050 JvmtiEnv::GetImplementedInterfaces(oop k_mirror, jint* interface_count_ptr, jclass** interfaces_ptr) {
3051   {
3052     if (java_lang_Class::is_primitive(k_mirror)) {
3053       *interface_count_ptr = 0;
3054       *interfaces_ptr = (jclass*) jvmtiMalloc(0 * sizeof(jclass));
3055       return JVMTI_ERROR_NONE;
3056     }
3057     JavaThread* current_thread = JavaThread::current();
3058     HandleMark hm(current_thread);
3059     Klass* k = java_lang_Class::as_Klass(k_mirror);
3060     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3061 
3062     // Return CLASS_NOT_PREPARED error as per JVMTI spec.
3063     if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) ))
3064       return JVMTI_ERROR_CLASS_NOT_PREPARED;
3065 
3066     if (!k->is_instance_klass()) {
3067       *interface_count_ptr = 0;
3068       *interfaces_ptr = (jclass*) jvmtiMalloc(0 * sizeof(jclass));
3069       return JVMTI_ERROR_NONE;
3070     }
3071 
3072     InstanceKlass* ik = InstanceKlass::cast(k);
3073     Array<InstanceKlass*>* interface_list = ik->local_interfaces();
3074     int result_length = (interface_list == nullptr ? 0 : interface_list->length());
3075     jclass* result_list = (jclass*) jvmtiMalloc(result_length * sizeof(jclass));
3076     for (int i_index = 0; i_index < result_length; i_index += 1) {
3077       InstanceKlass* klass_at = interface_list->at(i_index);
3078       assert(klass_at->is_klass(), "interfaces must be Klass*s");
3079       assert(klass_at->is_interface(), "interfaces must be interfaces");
3080       oop mirror_at = klass_at->java_mirror();
3081       Handle handle_at = Handle(current_thread, mirror_at);
3082       result_list[i_index] = (jclass) jni_reference(handle_at);
3083     }
3084     *interface_count_ptr = result_length;
3085     *interfaces_ptr = result_list;
3086   }
3087 
3088   return JVMTI_ERROR_NONE;
3089 } /* end GetImplementedInterfaces */
3090 
3091 
3092 // k_mirror - may be primitive, this must be checked
3093 // minor_version_ptr - pre-checked for null
3094 // major_version_ptr - pre-checked for null
3095 jvmtiError
3096 JvmtiEnv::GetClassVersionNumbers(oop k_mirror, jint* minor_version_ptr, jint* major_version_ptr) {
3097   if (java_lang_Class::is_primitive(k_mirror)) {
3098     return JVMTI_ERROR_ABSENT_INFORMATION;
3099   }
3100   Klass* klass = java_lang_Class::as_Klass(k_mirror);
3101 
3102   jint status = klass->jvmti_class_status();
3103   if (status & (JVMTI_CLASS_STATUS_ERROR)) {
3104     return JVMTI_ERROR_INVALID_CLASS;
3105   }
3106   if (status & (JVMTI_CLASS_STATUS_ARRAY)) {
3107     return JVMTI_ERROR_ABSENT_INFORMATION;
3108   }
3109 
3110   InstanceKlass* ik = InstanceKlass::cast(klass);
3111   *minor_version_ptr = ik->minor_version();
3112   *major_version_ptr = ik->major_version();
3113 
3114   return JVMTI_ERROR_NONE;
3115 } /* end GetClassVersionNumbers */
3116 
3117 
3118 // k_mirror - may be primitive, this must be checked
3119 // constant_pool_count_ptr - pre-checked for null
3120 // constant_pool_byte_count_ptr - pre-checked for null
3121 // constant_pool_bytes_ptr - pre-checked for null
3122 jvmtiError
3123 JvmtiEnv::GetConstantPool(oop k_mirror, jint* constant_pool_count_ptr, jint* constant_pool_byte_count_ptr, unsigned char** constant_pool_bytes_ptr) {
3124   if (java_lang_Class::is_primitive(k_mirror)) {
3125     return JVMTI_ERROR_ABSENT_INFORMATION;
3126   }
3127 
3128   Klass* klass = java_lang_Class::as_Klass(k_mirror);
3129   Thread *thread = Thread::current();
3130   ResourceMark rm(thread);
3131 
3132   jint status = klass->jvmti_class_status();
3133   if (status & (JVMTI_CLASS_STATUS_ERROR)) {
3134     return JVMTI_ERROR_INVALID_CLASS;
3135   }
3136   if (status & (JVMTI_CLASS_STATUS_ARRAY)) {
3137     return JVMTI_ERROR_ABSENT_INFORMATION;
3138   }
3139 
3140   InstanceKlass* ik = InstanceKlass::cast(klass);
3141   JvmtiConstantPoolReconstituter reconstituter(ik);
3142   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
3143     return reconstituter.get_error();
3144   }
3145 
3146   unsigned char *cpool_bytes;
3147   int cpool_size = reconstituter.cpool_size();
3148   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
3149     return reconstituter.get_error();
3150   }
3151   jvmtiError res = allocate(cpool_size, &cpool_bytes);
3152   if (res != JVMTI_ERROR_NONE) {
3153     return res;
3154   }
3155   reconstituter.copy_cpool_bytes(cpool_bytes);
3156   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
3157     return reconstituter.get_error();
3158   }
3159 
3160   constantPoolHandle  constants(thread, ik->constants());
3161   *constant_pool_count_ptr      = constants->length();
3162   *constant_pool_byte_count_ptr = cpool_size;
3163   *constant_pool_bytes_ptr      = cpool_bytes;
3164 
3165   return JVMTI_ERROR_NONE;
3166 } /* end GetConstantPool */
3167 
3168 
3169 // k_mirror - may be primitive, this must be checked
3170 // is_interface_ptr - pre-checked for null
3171 jvmtiError
3172 JvmtiEnv::IsInterface(oop k_mirror, jboolean* is_interface_ptr) {
3173   {
3174     bool result = false;
3175     if (!java_lang_Class::is_primitive(k_mirror)) {
3176       Klass* k = java_lang_Class::as_Klass(k_mirror);
3177       if (k != nullptr && k->is_interface()) {
3178         result = true;
3179       }
3180     }
3181     *is_interface_ptr = result;
3182   }
3183 
3184   return JVMTI_ERROR_NONE;
3185 } /* end IsInterface */
3186 
3187 
3188 // k_mirror - may be primitive, this must be checked
3189 // is_array_class_ptr - pre-checked for null
3190 jvmtiError
3191 JvmtiEnv::IsArrayClass(oop k_mirror, jboolean* is_array_class_ptr) {
3192   {
3193     bool result = false;
3194     if (!java_lang_Class::is_primitive(k_mirror)) {
3195       Klass* k = java_lang_Class::as_Klass(k_mirror);
3196       if (k != nullptr && k->is_array_klass()) {
3197         result = true;
3198       }
3199     }
3200     *is_array_class_ptr = result;
3201   }
3202 
3203   return JVMTI_ERROR_NONE;
3204 } /* end IsArrayClass */
3205 
3206 
3207 // k_mirror - may be primitive, this must be checked
3208 // classloader_ptr - pre-checked for null
3209 jvmtiError
3210 JvmtiEnv::GetClassLoader(oop k_mirror, jobject* classloader_ptr) {
3211   {
3212     if (java_lang_Class::is_primitive(k_mirror)) {
3213       *classloader_ptr = (jclass) jni_reference(Handle());
3214       return JVMTI_ERROR_NONE;
3215     }
3216     JavaThread* current_thread = JavaThread::current();
3217     HandleMark hm(current_thread);
3218     Klass* k = java_lang_Class::as_Klass(k_mirror);
3219     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3220 
3221     oop result_oop = k->class_loader();
3222     if (result_oop == nullptr) {
3223       *classloader_ptr = (jclass) jni_reference(Handle());
3224       return JVMTI_ERROR_NONE;
3225     }
3226     Handle result_handle = Handle(current_thread, result_oop);
3227     jclass result_jnihandle = (jclass) jni_reference(result_handle);
3228     *classloader_ptr = result_jnihandle;
3229   }
3230   return JVMTI_ERROR_NONE;
3231 } /* end GetClassLoader */
3232 
3233 
3234 // k_mirror - may be primitive, this must be checked
3235 // source_debug_extension_ptr - pre-checked for null
3236 jvmtiError
3237 JvmtiEnv::GetSourceDebugExtension(oop k_mirror, char** source_debug_extension_ptr) {
3238   {
3239     if (java_lang_Class::is_primitive(k_mirror)) {
3240       return JVMTI_ERROR_ABSENT_INFORMATION;
3241     }
3242     Klass* k = java_lang_Class::as_Klass(k_mirror);
3243     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3244     if (!k->is_instance_klass()) {
3245       return JVMTI_ERROR_ABSENT_INFORMATION;
3246     }
3247     const char* sde = InstanceKlass::cast(k)->source_debug_extension();
3248     NULL_CHECK(sde, JVMTI_ERROR_ABSENT_INFORMATION);
3249 
3250     {
3251       *source_debug_extension_ptr = (char *) jvmtiMalloc(strlen(sde)+1);
3252       strcpy(*source_debug_extension_ptr, sde);
3253     }
3254   }
3255 
3256   return JVMTI_ERROR_NONE;
3257 } /* end GetSourceDebugExtension */
3258 
3259   //
3260   // Object functions
3261   //
3262 
3263 // hash_code_ptr - pre-checked for null
3264 jvmtiError
3265 JvmtiEnv::GetObjectHashCode(jobject object, jint* hash_code_ptr) {
3266   oop mirror = JNIHandles::resolve_external_guard(object);
3267   NULL_CHECK(mirror, JVMTI_ERROR_INVALID_OBJECT);
3268   NULL_CHECK(hash_code_ptr, JVMTI_ERROR_NULL_POINTER);
3269 
3270   {
3271     jint result = (jint) mirror->identity_hash();
3272     *hash_code_ptr = result;
3273   }
3274   return JVMTI_ERROR_NONE;
3275 } /* end GetObjectHashCode */
3276 
3277 
3278 // info_ptr - pre-checked for null
3279 jvmtiError
3280 JvmtiEnv::GetObjectMonitorUsage(jobject object, jvmtiMonitorUsage* info_ptr) {
3281   // This needs to be performed at a safepoint to gather stable data
3282   // because monitor owner / waiters might not be suspended.
3283   VM_GetObjectMonitorUsage op(this, JavaThread::current(), object, info_ptr);
3284   VMThread::execute(&op);
3285   return op.result();
3286 } /* end GetObjectMonitorUsage */
3287 
3288 
3289   //
3290   // Field functions
3291   //
3292 
3293 // name_ptr - null is a valid value, must be checked
3294 // signature_ptr - null is a valid value, must be checked
3295 // generic_ptr - null is a valid value, must be checked
3296 jvmtiError
3297 JvmtiEnv::GetFieldName(fieldDescriptor* fdesc_ptr, char** name_ptr, char** signature_ptr, char** generic_ptr) {
3298   JavaThread* current_thread  = JavaThread::current();
3299   ResourceMark rm(current_thread);
3300   if (name_ptr == nullptr) {
3301     // just don't return the name
3302   } else {
3303     const char* fieldName = fdesc_ptr->name()->as_C_string();
3304     *name_ptr =  (char*) jvmtiMalloc(strlen(fieldName) + 1);
3305     if (*name_ptr == nullptr)
3306       return JVMTI_ERROR_OUT_OF_MEMORY;
3307     strcpy(*name_ptr, fieldName);
3308   }
3309   if (signature_ptr== nullptr) {
3310     // just don't return the signature
3311   } else {
3312     const char* fieldSignature = fdesc_ptr->signature()->as_C_string();
3313     *signature_ptr = (char*) jvmtiMalloc(strlen(fieldSignature) + 1);
3314     if (*signature_ptr == nullptr)
3315       return JVMTI_ERROR_OUT_OF_MEMORY;
3316     strcpy(*signature_ptr, fieldSignature);
3317   }
3318   if (generic_ptr != nullptr) {
3319     *generic_ptr = nullptr;
3320     Symbol* soop = fdesc_ptr->generic_signature();
3321     if (soop != nullptr) {
3322       const char* gen_sig = soop->as_C_string();
3323       if (gen_sig != nullptr) {
3324         jvmtiError err = allocate(strlen(gen_sig) + 1, (unsigned char **)generic_ptr);
3325         if (err != JVMTI_ERROR_NONE) {
3326           return err;
3327         }
3328         strcpy(*generic_ptr, gen_sig);
3329       }
3330     }
3331   }
3332   return JVMTI_ERROR_NONE;
3333 } /* end GetFieldName */
3334 
3335 
3336 // declaring_class_ptr - pre-checked for null
3337 jvmtiError
3338 JvmtiEnv::GetFieldDeclaringClass(fieldDescriptor* fdesc_ptr, jclass* declaring_class_ptr) {
3339 
3340   *declaring_class_ptr = get_jni_class_non_null(fdesc_ptr->field_holder());
3341   return JVMTI_ERROR_NONE;
3342 } /* end GetFieldDeclaringClass */
3343 
3344 
3345 // modifiers_ptr - pre-checked for null
3346 jvmtiError
3347 JvmtiEnv::GetFieldModifiers(fieldDescriptor* fdesc_ptr, jint* modifiers_ptr) {
3348 
3349   AccessFlags resultFlags = fdesc_ptr->access_flags();
3350   jint result = resultFlags.as_int();
3351   *modifiers_ptr = result;
3352 
3353   return JVMTI_ERROR_NONE;
3354 } /* end GetFieldModifiers */
3355 
3356 
3357 // is_synthetic_ptr - pre-checked for null
3358 jvmtiError
3359 JvmtiEnv::IsFieldSynthetic(fieldDescriptor* fdesc_ptr, jboolean* is_synthetic_ptr) {
3360   *is_synthetic_ptr = fdesc_ptr->is_synthetic();
3361   return JVMTI_ERROR_NONE;
3362 } /* end IsFieldSynthetic */
3363 
3364 
3365   //
3366   // Method functions
3367   //
3368 
3369 // method - pre-checked for validity, but may be null meaning obsolete method
3370 // name_ptr - null is a valid value, must be checked
3371 // signature_ptr - null is a valid value, must be checked
3372 // generic_ptr - null is a valid value, must be checked
3373 jvmtiError
3374 JvmtiEnv::GetMethodName(Method* method, char** name_ptr, char** signature_ptr, char** generic_ptr) {
3375   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3376   JavaThread* current_thread  = JavaThread::current();
3377 
3378   ResourceMark rm(current_thread); // get the utf8 name and signature
3379   if (name_ptr == nullptr) {
3380     // just don't return the name
3381   } else {
3382     const char* utf8_name = (const char *) method->name()->as_utf8();
3383     *name_ptr = (char *) jvmtiMalloc(strlen(utf8_name)+1);
3384     strcpy(*name_ptr, utf8_name);
3385   }
3386   if (signature_ptr == nullptr) {
3387     // just don't return the signature
3388   } else {
3389     const char* utf8_signature = (const char *) method->signature()->as_utf8();
3390     *signature_ptr = (char *) jvmtiMalloc(strlen(utf8_signature) + 1);
3391     strcpy(*signature_ptr, utf8_signature);
3392   }
3393 
3394   if (generic_ptr != nullptr) {
3395     *generic_ptr = nullptr;
3396     Symbol* soop = method->generic_signature();
3397     if (soop != nullptr) {
3398       const char* gen_sig = soop->as_C_string();
3399       if (gen_sig != nullptr) {
3400         jvmtiError err = allocate(strlen(gen_sig) + 1, (unsigned char **)generic_ptr);
3401         if (err != JVMTI_ERROR_NONE) {
3402           return err;
3403         }
3404         strcpy(*generic_ptr, gen_sig);
3405       }
3406     }
3407   }
3408   return JVMTI_ERROR_NONE;
3409 } /* end GetMethodName */
3410 
3411 
3412 // method - pre-checked for validity, but may be null meaning obsolete method
3413 // declaring_class_ptr - pre-checked for null
3414 jvmtiError
3415 JvmtiEnv::GetMethodDeclaringClass(Method* method, jclass* declaring_class_ptr) {
3416   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3417   (*declaring_class_ptr) = get_jni_class_non_null(method->method_holder());
3418   return JVMTI_ERROR_NONE;
3419 } /* end GetMethodDeclaringClass */
3420 
3421 
3422 // method - pre-checked for validity, but may be null meaning obsolete method
3423 // modifiers_ptr - pre-checked for null
3424 jvmtiError
3425 JvmtiEnv::GetMethodModifiers(Method* method, jint* modifiers_ptr) {
3426   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3427   (*modifiers_ptr) = method->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS;
3428   return JVMTI_ERROR_NONE;
3429 } /* end GetMethodModifiers */
3430 
3431 
3432 // method - pre-checked for validity, but may be null meaning obsolete method
3433 // max_ptr - pre-checked for null
3434 jvmtiError
3435 JvmtiEnv::GetMaxLocals(Method* method, jint* max_ptr) {
3436   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3437   // get max stack
3438   (*max_ptr) = method->max_locals();
3439   return JVMTI_ERROR_NONE;
3440 } /* end GetMaxLocals */
3441 
3442 
3443 // method - pre-checked for validity, but may be null meaning obsolete method
3444 // size_ptr - pre-checked for null
3445 jvmtiError
3446 JvmtiEnv::GetArgumentsSize(Method* method, jint* size_ptr) {
3447   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3448   // get size of arguments
3449 
3450   (*size_ptr) = method->size_of_parameters();
3451   return JVMTI_ERROR_NONE;
3452 } /* end GetArgumentsSize */
3453 
3454 
3455 // method - pre-checked for validity, but may be null meaning obsolete method
3456 // entry_count_ptr - pre-checked for null
3457 // table_ptr - pre-checked for null
3458 jvmtiError
3459 JvmtiEnv::GetLineNumberTable(Method* method, jint* entry_count_ptr, jvmtiLineNumberEntry** table_ptr) {
3460   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3461   if (!method->has_linenumber_table()) {
3462     return (JVMTI_ERROR_ABSENT_INFORMATION);
3463   }
3464 
3465   // The line number table is compressed so we don't know how big it is until decompressed.
3466   // Decompression is really fast so we just do it twice.
3467 
3468   // Compute size of table
3469   jint num_entries = 0;
3470   CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
3471   while (stream.read_pair()) {
3472     num_entries++;
3473   }
3474   jvmtiLineNumberEntry *jvmti_table =
3475             (jvmtiLineNumberEntry *)jvmtiMalloc(num_entries * (sizeof(jvmtiLineNumberEntry)));
3476 
3477   // Fill jvmti table
3478   if (num_entries > 0) {
3479     int index = 0;
3480     CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
3481     while (stream.read_pair()) {
3482       jvmti_table[index].start_location = (jlocation) stream.bci();
3483       jvmti_table[index].line_number = (jint) stream.line();
3484       index++;
3485     }
3486     assert(index == num_entries, "sanity check");
3487   }
3488 
3489   // Set up results
3490   (*entry_count_ptr) = num_entries;
3491   (*table_ptr) = jvmti_table;
3492 
3493   return JVMTI_ERROR_NONE;
3494 } /* end GetLineNumberTable */
3495 
3496 
3497 // method - pre-checked for validity, but may be null meaning obsolete method
3498 // start_location_ptr - pre-checked for null
3499 // end_location_ptr - pre-checked for null
3500 jvmtiError
3501 JvmtiEnv::GetMethodLocation(Method* method, jlocation* start_location_ptr, jlocation* end_location_ptr) {
3502 
3503   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3504   // get start and end location
3505   (*end_location_ptr) = (jlocation) (method->code_size() - 1);
3506   if (method->code_size() == 0) {
3507     // there is no code so there is no start location
3508     (*start_location_ptr) = (jlocation)(-1);
3509   } else {
3510     (*start_location_ptr) = (jlocation)(0);
3511   }
3512 
3513   return JVMTI_ERROR_NONE;
3514 } /* end GetMethodLocation */
3515 
3516 
3517 // method - pre-checked for validity, but may be null meaning obsolete method
3518 // entry_count_ptr - pre-checked for null
3519 // table_ptr - pre-checked for null
3520 jvmtiError
3521 JvmtiEnv::GetLocalVariableTable(Method* method, jint* entry_count_ptr, jvmtiLocalVariableEntry** table_ptr) {
3522 
3523   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3524   JavaThread* current_thread  = JavaThread::current();
3525 
3526   // does the klass have any local variable information?
3527   InstanceKlass* ik = method->method_holder();
3528   if (!ik->has_localvariable_table()) {
3529     return (JVMTI_ERROR_ABSENT_INFORMATION);
3530   }
3531 
3532   ConstantPool* constants = method->constants();
3533   NULL_CHECK(constants, JVMTI_ERROR_ABSENT_INFORMATION);
3534 
3535   // in the vm localvariable table representation, 6 consecutive elements in the table
3536   // represent a 6-tuple of shorts
3537   // [start_pc, length, name_index, descriptor_index, signature_index, index]
3538   jint num_entries = method->localvariable_table_length();
3539   jvmtiLocalVariableEntry *jvmti_table = (jvmtiLocalVariableEntry *)
3540                 jvmtiMalloc(num_entries * (sizeof(jvmtiLocalVariableEntry)));
3541 
3542   if (num_entries > 0) {
3543     LocalVariableTableElement* table = method->localvariable_table_start();
3544     for (int i = 0; i < num_entries; i++) {
3545       // get the 5 tuple information from the vm table
3546       jlocation start_location = (jlocation) table[i].start_bci;
3547       jint length = (jint) table[i].length;
3548       int name_index = (int) table[i].name_cp_index;
3549       int signature_index = (int) table[i].descriptor_cp_index;
3550       int generic_signature_index = (int) table[i].signature_cp_index;
3551       jint slot = (jint) table[i].slot;
3552 
3553       // get utf8 name and signature
3554       char *name_buf = nullptr;
3555       char *sig_buf = nullptr;
3556       char *gen_sig_buf = nullptr;
3557       {
3558         ResourceMark rm(current_thread);
3559 
3560         const char *utf8_name = (const char *) constants->symbol_at(name_index)->as_utf8();
3561         name_buf = (char *) jvmtiMalloc(strlen(utf8_name)+1);
3562         strcpy(name_buf, utf8_name);
3563 
3564         const char *utf8_signature = (const char *) constants->symbol_at(signature_index)->as_utf8();
3565         sig_buf = (char *) jvmtiMalloc(strlen(utf8_signature)+1);
3566         strcpy(sig_buf, utf8_signature);
3567 
3568         if (generic_signature_index > 0) {
3569           const char *utf8_gen_sign = (const char *)
3570                                        constants->symbol_at(generic_signature_index)->as_utf8();
3571           gen_sig_buf = (char *) jvmtiMalloc(strlen(utf8_gen_sign)+1);
3572           strcpy(gen_sig_buf, utf8_gen_sign);
3573         }
3574       }
3575 
3576       // fill in the jvmti local variable table
3577       jvmti_table[i].start_location = start_location;
3578       jvmti_table[i].length = length;
3579       jvmti_table[i].name = name_buf;
3580       jvmti_table[i].signature = sig_buf;
3581       jvmti_table[i].generic_signature = gen_sig_buf;
3582       jvmti_table[i].slot = slot;
3583     }
3584   }
3585 
3586   // set results
3587   (*entry_count_ptr) = num_entries;
3588   (*table_ptr) = jvmti_table;
3589 
3590   return JVMTI_ERROR_NONE;
3591 } /* end GetLocalVariableTable */
3592 
3593 
3594 // method - pre-checked for validity, but may be null meaning obsolete method
3595 // bytecode_count_ptr - pre-checked for null
3596 // bytecodes_ptr - pre-checked for null
3597 jvmtiError
3598 JvmtiEnv::GetBytecodes(Method* method, jint* bytecode_count_ptr, unsigned char** bytecodes_ptr) {
3599   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3600 
3601   methodHandle mh(Thread::current(), method);
3602   jint size = (jint)mh->code_size();
3603   jvmtiError err = allocate(size, bytecodes_ptr);
3604   if (err != JVMTI_ERROR_NONE) {
3605     return err;
3606   }
3607 
3608   (*bytecode_count_ptr) = size;
3609   // get byte codes
3610   JvmtiClassFileReconstituter::copy_bytecodes(mh, *bytecodes_ptr);
3611 
3612   return JVMTI_ERROR_NONE;
3613 } /* end GetBytecodes */
3614 
3615 
3616 // method - pre-checked for validity, but may be null meaning obsolete method
3617 // is_native_ptr - pre-checked for null
3618 jvmtiError
3619 JvmtiEnv::IsMethodNative(Method* method, jboolean* is_native_ptr) {
3620   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3621   (*is_native_ptr) = method->is_native();
3622   return JVMTI_ERROR_NONE;
3623 } /* end IsMethodNative */
3624 
3625 
3626 // method - pre-checked for validity, but may be null meaning obsolete method
3627 // is_synthetic_ptr - pre-checked for null
3628 jvmtiError
3629 JvmtiEnv::IsMethodSynthetic(Method* method, jboolean* is_synthetic_ptr) {
3630   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3631   (*is_synthetic_ptr) = method->is_synthetic();
3632   return JVMTI_ERROR_NONE;
3633 } /* end IsMethodSynthetic */
3634 
3635 
3636 // method - pre-checked for validity, but may be null meaning obsolete method
3637 // is_obsolete_ptr - pre-checked for null
3638 jvmtiError
3639 JvmtiEnv::IsMethodObsolete(Method* method, jboolean* is_obsolete_ptr) {
3640   if (use_version_1_0_semantics() &&
3641       get_capabilities()->can_redefine_classes == 0) {
3642     // This JvmtiEnv requested version 1.0 semantics and this function
3643     // requires the can_redefine_classes capability in version 1.0 so
3644     // we need to return an error here.
3645     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
3646   }
3647 
3648   if (method == nullptr || method->is_obsolete()) {
3649     *is_obsolete_ptr = true;
3650   } else {
3651     *is_obsolete_ptr = false;
3652   }
3653   return JVMTI_ERROR_NONE;
3654 } /* end IsMethodObsolete */
3655 
3656   //
3657   // Raw Monitor functions
3658   //
3659 
3660 // name - pre-checked for null
3661 // monitor_ptr - pre-checked for null
3662 jvmtiError
3663 JvmtiEnv::CreateRawMonitor(const char* name, jrawMonitorID* monitor_ptr) {
3664   JvmtiRawMonitor* rmonitor = new (std::nothrow) JvmtiRawMonitor(name);
3665   NULL_CHECK(rmonitor, JVMTI_ERROR_OUT_OF_MEMORY);
3666 
3667   *monitor_ptr = (jrawMonitorID)rmonitor;
3668 
3669   return JVMTI_ERROR_NONE;
3670 } /* end CreateRawMonitor */
3671 
3672 
3673 // rmonitor - pre-checked for validity
3674 jvmtiError
3675 JvmtiEnv::DestroyRawMonitor(JvmtiRawMonitor * rmonitor) {
3676   if (Threads::number_of_threads() == 0) {
3677     // Remove this monitor from pending raw monitors list
3678     // if it has entered in onload or start phase.
3679     JvmtiPendingMonitors::destroy(rmonitor);
3680   } else {
3681     Thread* thread  = Thread::current();
3682     if (rmonitor->owner() == thread) {
3683       // The caller owns this monitor which we are about to destroy.
3684       // We exit the underlying synchronization object so that the
3685       // "delete monitor" call below can work without an assertion
3686       // failure on systems that don't like destroying synchronization
3687       // objects that are locked.
3688       int r;
3689       int recursion = rmonitor->recursions();
3690       for (int i = 0; i <= recursion; i++) {
3691         r = rmonitor->raw_exit(thread);
3692         assert(r == JvmtiRawMonitor::M_OK, "raw_exit should have worked");
3693         if (r != JvmtiRawMonitor::M_OK) {  // robustness
3694           return JVMTI_ERROR_INTERNAL;
3695         }
3696       }
3697     }
3698     if (rmonitor->owner() != nullptr) {
3699       // The caller is trying to destroy a monitor that is locked by
3700       // someone else. While this is not forbidden by the JVMTI
3701       // spec, it will cause an assertion failure on systems that don't
3702       // like destroying synchronization objects that are locked.
3703       // We indicate a problem with the error return (and leak the
3704       // monitor's memory).
3705       return JVMTI_ERROR_NOT_MONITOR_OWNER;
3706     }
3707   }
3708 
3709   delete rmonitor;
3710 
3711   return JVMTI_ERROR_NONE;
3712 } /* end DestroyRawMonitor */
3713 
3714 
3715 // rmonitor - pre-checked for validity
3716 jvmtiError
3717 JvmtiEnv::RawMonitorEnter(JvmtiRawMonitor * rmonitor) {
3718   if (Threads::number_of_threads() == 0) {
3719     // No JavaThreads exist so JvmtiRawMonitor enter cannot be
3720     // used, add this raw monitor to the pending list.
3721     // The pending monitors will be actually entered when
3722     // the VM is setup.
3723     // See transition_pending_raw_monitors in create_vm()
3724     // in thread.cpp.
3725     JvmtiPendingMonitors::enter(rmonitor);
3726   } else {
3727     Thread* thread = Thread::current();
3728     // 8266889: raw_enter changes Java thread state, needs WXWrite
3729     MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
3730     rmonitor->raw_enter(thread);
3731   }
3732   return JVMTI_ERROR_NONE;
3733 } /* end RawMonitorEnter */
3734 
3735 
3736 // rmonitor - pre-checked for validity
3737 jvmtiError
3738 JvmtiEnv::RawMonitorExit(JvmtiRawMonitor * rmonitor) {
3739   jvmtiError err = JVMTI_ERROR_NONE;
3740 
3741   if (Threads::number_of_threads() == 0) {
3742     // No JavaThreads exist so just remove this monitor from the pending list.
3743     // Bool value from exit is false if rmonitor is not in the list.
3744     if (!JvmtiPendingMonitors::exit(rmonitor)) {
3745       err = JVMTI_ERROR_NOT_MONITOR_OWNER;
3746     }
3747   } else {
3748     Thread* thread = Thread::current();
3749     int r = rmonitor->raw_exit(thread);
3750     if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3751       err = JVMTI_ERROR_NOT_MONITOR_OWNER;
3752     }
3753   }
3754   return err;
3755 } /* end RawMonitorExit */
3756 
3757 
3758 // rmonitor - pre-checked for validity
3759 jvmtiError
3760 JvmtiEnv::RawMonitorWait(JvmtiRawMonitor * rmonitor, jlong millis) {
3761   Thread* thread = Thread::current();
3762   // 8266889: raw_wait changes Java thread state, needs WXWrite
3763   MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
3764   int r = rmonitor->raw_wait(millis, thread);
3765 
3766   switch (r) {
3767   case JvmtiRawMonitor::M_INTERRUPTED:
3768     return JVMTI_ERROR_INTERRUPT;
3769   case JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE:
3770     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3771   default:
3772     return JVMTI_ERROR_NONE;
3773   }
3774 } /* end RawMonitorWait */
3775 
3776 
3777 // rmonitor - pre-checked for validity
3778 jvmtiError
3779 JvmtiEnv::RawMonitorNotify(JvmtiRawMonitor * rmonitor) {
3780   Thread* thread = Thread::current();
3781   int r = rmonitor->raw_notify(thread);
3782 
3783   if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3784     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3785   }
3786   return JVMTI_ERROR_NONE;
3787 } /* end RawMonitorNotify */
3788 
3789 
3790 // rmonitor - pre-checked for validity
3791 jvmtiError
3792 JvmtiEnv::RawMonitorNotifyAll(JvmtiRawMonitor * rmonitor) {
3793   Thread* thread = Thread::current();
3794   int r = rmonitor->raw_notifyAll(thread);
3795 
3796   if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3797     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3798   }
3799   return JVMTI_ERROR_NONE;
3800 } /* end RawMonitorNotifyAll */
3801 
3802 
3803   //
3804   // JNI Function Interception functions
3805   //
3806 
3807 
3808 // function_table - pre-checked for null
3809 jvmtiError
3810 JvmtiEnv::SetJNIFunctionTable(const jniNativeInterface* function_table) {
3811   // Copy jni function table at safepoint.
3812   VM_JNIFunctionTableCopier copier(function_table);
3813   VMThread::execute(&copier);
3814 
3815   return JVMTI_ERROR_NONE;
3816 } /* end SetJNIFunctionTable */
3817 
3818 
3819 // function_table - pre-checked for null
3820 jvmtiError
3821 JvmtiEnv::GetJNIFunctionTable(jniNativeInterface** function_table) {
3822   *function_table=(jniNativeInterface*)jvmtiMalloc(sizeof(jniNativeInterface));
3823   if (*function_table == nullptr)
3824     return JVMTI_ERROR_OUT_OF_MEMORY;
3825   memcpy(*function_table,(JavaThread::current())->get_jni_functions(),sizeof(jniNativeInterface));
3826   return JVMTI_ERROR_NONE;
3827 } /* end GetJNIFunctionTable */
3828 
3829 
3830   //
3831   // Event Management functions
3832   //
3833 
3834 jvmtiError
3835 JvmtiEnv::GenerateEvents(jvmtiEvent event_type) {
3836   // can only generate two event types
3837   if (event_type != JVMTI_EVENT_COMPILED_METHOD_LOAD &&
3838       event_type != JVMTI_EVENT_DYNAMIC_CODE_GENERATED) {
3839     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
3840   }
3841 
3842   // for compiled_method_load events we must check that the environment
3843   // has the can_generate_compiled_method_load_events capability.
3844   if (event_type == JVMTI_EVENT_COMPILED_METHOD_LOAD) {
3845     if (get_capabilities()->can_generate_compiled_method_load_events == 0) {
3846       return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
3847     }
3848     return JvmtiCodeBlobEvents::generate_compiled_method_load_events(this);
3849   } else {
3850     return JvmtiCodeBlobEvents::generate_dynamic_code_events(this);
3851   }
3852 
3853 } /* end GenerateEvents */
3854 
3855 
3856   //
3857   // Extension Mechanism functions
3858   //
3859 
3860 // extension_count_ptr - pre-checked for null
3861 // extensions - pre-checked for null
3862 jvmtiError
3863 JvmtiEnv::GetExtensionFunctions(jint* extension_count_ptr, jvmtiExtensionFunctionInfo** extensions) {
3864   return JvmtiExtensions::get_functions(this, extension_count_ptr, extensions);
3865 } /* end GetExtensionFunctions */
3866 
3867 
3868 // extension_count_ptr - pre-checked for null
3869 // extensions - pre-checked for null
3870 jvmtiError
3871 JvmtiEnv::GetExtensionEvents(jint* extension_count_ptr, jvmtiExtensionEventInfo** extensions) {
3872   return JvmtiExtensions::get_events(this, extension_count_ptr, extensions);
3873 } /* end GetExtensionEvents */
3874 
3875 
3876 // callback - null is a valid value, must be checked
3877 jvmtiError
3878 JvmtiEnv::SetExtensionEventCallback(jint extension_event_index, jvmtiExtensionEvent callback) {
3879   return JvmtiExtensions::set_event_callback(this, extension_event_index, callback);
3880 } /* end SetExtensionEventCallback */
3881 
3882   //
3883   // Timers functions
3884   //
3885 
3886 // info_ptr - pre-checked for null
3887 jvmtiError
3888 JvmtiEnv::GetCurrentThreadCpuTimerInfo(jvmtiTimerInfo* info_ptr) {
3889   os::current_thread_cpu_time_info(info_ptr);
3890   return JVMTI_ERROR_NONE;
3891 } /* end GetCurrentThreadCpuTimerInfo */
3892 
3893 
3894 // nanos_ptr - pre-checked for null
3895 jvmtiError
3896 JvmtiEnv::GetCurrentThreadCpuTime(jlong* nanos_ptr) {
3897   Thread* thread = Thread::current();
3898 
3899   // Surprisingly the GetCurrentThreadCpuTime is used by non-JavaThread's.
3900   if (thread->is_Java_thread()) {
3901     if (JavaThread::cast(thread)->is_vthread_mounted()) {
3902       // No support for a VirtualThread (yet).
3903       return JVMTI_ERROR_UNSUPPORTED_OPERATION;
3904     }
3905   }
3906   *nanos_ptr = os::current_thread_cpu_time();
3907   return JVMTI_ERROR_NONE;
3908 } /* end GetCurrentThreadCpuTime */
3909 
3910 
3911 // info_ptr - pre-checked for null
3912 jvmtiError
3913 JvmtiEnv::GetThreadCpuTimerInfo(jvmtiTimerInfo* info_ptr) {
3914   os::thread_cpu_time_info(info_ptr);
3915   return JVMTI_ERROR_NONE;
3916 } /* end GetThreadCpuTimerInfo */
3917 
3918 
3919 // nanos_ptr - pre-checked for null
3920 jvmtiError
3921 JvmtiEnv::GetThreadCpuTime(jthread thread, jlong* nanos_ptr) {
3922   JavaThread* current_thread = JavaThread::current();
3923   ThreadsListHandle tlh(current_thread);
3924   JavaThread* java_thread = nullptr;
3925   oop thread_oop = nullptr;
3926 
3927   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
3928 
3929   if (thread_oop != nullptr && thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
3930     // No support for virtual threads (yet).
3931     return JVMTI_ERROR_UNSUPPORTED_OPERATION;
3932   }
3933   if (err != JVMTI_ERROR_NONE) {
3934     return err;
3935   }
3936   NULL_CHECK(nanos_ptr, JVMTI_ERROR_NULL_POINTER);
3937 
3938   *nanos_ptr = os::thread_cpu_time(java_thread);
3939   return JVMTI_ERROR_NONE;
3940 } /* end GetThreadCpuTime */
3941 
3942 
3943 // info_ptr - pre-checked for null
3944 jvmtiError
3945 JvmtiEnv::GetTimerInfo(jvmtiTimerInfo* info_ptr) {
3946   os::javaTimeNanos_info(info_ptr);
3947   return JVMTI_ERROR_NONE;
3948 } /* end GetTimerInfo */
3949 
3950 
3951 // nanos_ptr - pre-checked for null
3952 jvmtiError
3953 JvmtiEnv::GetTime(jlong* nanos_ptr) {
3954   *nanos_ptr = os::javaTimeNanos();
3955   return JVMTI_ERROR_NONE;
3956 } /* end GetTime */
3957 
3958 
3959 // processor_count_ptr - pre-checked for null
3960 jvmtiError
3961 JvmtiEnv::GetAvailableProcessors(jint* processor_count_ptr) {
3962   *processor_count_ptr = os::active_processor_count();
3963   return JVMTI_ERROR_NONE;
3964 } /* end GetAvailableProcessors */
3965 
3966 jvmtiError
3967 JvmtiEnv::SetHeapSamplingInterval(jint sampling_interval) {
3968   if (sampling_interval < 0) {
3969     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
3970   }
3971   ThreadHeapSampler::set_sampling_interval(sampling_interval);
3972   return JVMTI_ERROR_NONE;
3973 } /* end SetHeapSamplingInterval */
3974 
3975   //
3976   // System Properties functions
3977   //
3978 
3979 // count_ptr - pre-checked for null
3980 // property_ptr - pre-checked for null
3981 jvmtiError
3982 JvmtiEnv::GetSystemProperties(jint* count_ptr, char*** property_ptr) {
3983   jvmtiError err = JVMTI_ERROR_NONE;
3984 
3985   // Get the number of readable properties.
3986   *count_ptr = Arguments::PropertyList_readable_count(Arguments::system_properties());
3987 
3988   // Allocate memory to hold the exact number of readable properties.
3989   err = allocate(*count_ptr * sizeof(char *), (unsigned char **)property_ptr);
3990   if (err != JVMTI_ERROR_NONE) {
3991     return err;
3992   }
3993   int readable_count = 0;
3994   // Loop through the system properties until all the readable properties are found.
3995   for (SystemProperty* p = Arguments::system_properties(); p != nullptr && readable_count < *count_ptr; p = p->next()) {
3996     if (p->readable()) {
3997       const char *key = p->key();
3998       char **tmp_value = *property_ptr+readable_count;
3999       readable_count++;
4000       err = allocate((strlen(key)+1) * sizeof(char), (unsigned char**)tmp_value);
4001       if (err == JVMTI_ERROR_NONE) {
4002         strcpy(*tmp_value, key);
4003       } else {
4004         // clean up previously allocated memory.
4005         for (int j = 0; j < readable_count; j++) {
4006           Deallocate((unsigned char*)*property_ptr+j);
4007         }
4008         Deallocate((unsigned char*)property_ptr);
4009         break;
4010       }
4011     }
4012   }
4013   assert(err != JVMTI_ERROR_NONE || readable_count == *count_ptr, "Bad readable property count");
4014   return err;
4015 } /* end GetSystemProperties */
4016 
4017 
4018 // property - pre-checked for null
4019 // value_ptr - pre-checked for null
4020 jvmtiError
4021 JvmtiEnv::GetSystemProperty(const char* property, char** value_ptr) {
4022   jvmtiError err = JVMTI_ERROR_NONE;
4023   const char *value;
4024 
4025   // Return JVMTI_ERROR_NOT_AVAILABLE if property is not readable or doesn't exist.
4026   value = Arguments::PropertyList_get_readable_value(Arguments::system_properties(), property);
4027   if (value == nullptr) {
4028     err =  JVMTI_ERROR_NOT_AVAILABLE;
4029   } else {
4030     err = allocate((strlen(value)+1) * sizeof(char), (unsigned char **)value_ptr);
4031     if (err == JVMTI_ERROR_NONE) {
4032       strcpy(*value_ptr, value);
4033     }
4034   }
4035   return err;
4036 } /* end GetSystemProperty */
4037 
4038 
4039 // property - pre-checked for null
4040 // value - null is a valid value, must be checked
4041 jvmtiError
4042 JvmtiEnv::SetSystemProperty(const char* property, const char* value_ptr) {
4043   for (SystemProperty* p = Arguments::system_properties(); p != nullptr; p = p->next()) {
4044     if (strcmp(property, p->key()) == 0) {
4045       if (p->writeable()) {
4046         if (p->set_value(value_ptr, AllocFailStrategy::RETURN_NULL)) {
4047           return JVMTI_ERROR_NONE;
4048         } else {
4049           return JVMTI_ERROR_OUT_OF_MEMORY;
4050         }
4051       } else {
4052         // We found a property, but it's not writeable
4053         return JVMTI_ERROR_NOT_AVAILABLE;
4054       }
4055     }
4056   }
4057 
4058   // We cannot find a property of the given name
4059   return JVMTI_ERROR_NOT_AVAILABLE;
4060 } /* end SetSystemProperty */