1 /*
   2  * Copyright (c) 2003, 2024, 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, current, &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, current_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     JavaThread* current = JavaThread::current();
 590     ThreadsListHandle tlh(current);
 591 
 592     JavaThread* java_thread = nullptr;
 593     oop thread_obj = nullptr;
 594     jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), event_thread, current, &java_thread, &thread_obj);
 595     if (err != JVMTI_ERROR_NONE) {
 596       return err;
 597     }
 598 
 599     // global events cannot be controlled at thread level.
 600     if (JvmtiEventController::is_global_event(event_type)) {
 601       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 602     }
 603 
 604     JvmtiEventController::set_user_enabled(this, java_thread, thread_obj, event_type, enabled);
 605   }
 606 
 607   return JVMTI_ERROR_NONE;
 608 } /* end SetEventNotificationMode */
 609 
 610   //
 611   // Capability functions
 612   //
 613 
 614 // capabilities_ptr - pre-checked for null
 615 jvmtiError
 616 JvmtiEnv::GetPotentialCapabilities(jvmtiCapabilities* capabilities_ptr) {
 617   JvmtiManageCapabilities::get_potential_capabilities(get_capabilities(),
 618                                                       get_prohibited_capabilities(),
 619                                                       capabilities_ptr);
 620   return JVMTI_ERROR_NONE;
 621 } /* end GetPotentialCapabilities */
 622 
 623 
 624 // capabilities_ptr - pre-checked for null
 625 jvmtiError
 626 JvmtiEnv::AddCapabilities(const jvmtiCapabilities* capabilities_ptr) {
 627   return JvmtiManageCapabilities::add_capabilities(get_capabilities(),
 628                                                    get_prohibited_capabilities(),
 629                                                    capabilities_ptr,
 630                                                    get_capabilities());
 631 } /* end AddCapabilities */
 632 
 633 
 634 // capabilities_ptr - pre-checked for null
 635 jvmtiError
 636 JvmtiEnv::RelinquishCapabilities(const jvmtiCapabilities* capabilities_ptr) {
 637   JvmtiManageCapabilities::relinquish_capabilities(get_capabilities(), capabilities_ptr, get_capabilities());
 638   return JVMTI_ERROR_NONE;
 639 } /* end RelinquishCapabilities */
 640 
 641 
 642 // capabilities_ptr - pre-checked for null
 643 jvmtiError
 644 JvmtiEnv::GetCapabilities(jvmtiCapabilities* capabilities_ptr) {
 645   JvmtiManageCapabilities::copy_capabilities(get_capabilities(), capabilities_ptr);
 646   return JVMTI_ERROR_NONE;
 647 } /* end GetCapabilities */
 648 
 649   //
 650   // Class Loader Search functions
 651   //
 652 
 653 // segment - pre-checked for null
 654 jvmtiError
 655 JvmtiEnv::AddToBootstrapClassLoaderSearch(const char* segment) {
 656   jvmtiPhase phase = get_phase();
 657   if (phase == JVMTI_PHASE_ONLOAD) {
 658     Arguments::append_sysclasspath(segment);
 659     return JVMTI_ERROR_NONE;
 660   } else if (use_version_1_0_semantics()) {
 661     // This JvmtiEnv requested version 1.0 semantics and this function
 662     // is only allowed in the ONLOAD phase in version 1.0 so we need to
 663     // return an error here.
 664     return JVMTI_ERROR_WRONG_PHASE;
 665   } else if (phase == JVMTI_PHASE_LIVE) {
 666     // The phase is checked by the wrapper that called this function,
 667     // but this thread could be racing with the thread that is
 668     // terminating the VM so we check one more time.
 669 
 670     // create the zip entry
 671     ClassPathZipEntry* zip_entry = ClassLoader::create_class_path_zip_entry(segment, true);
 672     if (zip_entry == nullptr) {
 673       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 674     }
 675 
 676     // add the jar file to the bootclasspath
 677     log_info(class, load)("opened: %s", zip_entry->name());
 678 #if INCLUDE_CDS
 679     ClassLoaderExt::append_boot_classpath(zip_entry);
 680 #else
 681     ClassLoader::add_to_boot_append_entries(zip_entry);
 682 #endif
 683     return JVMTI_ERROR_NONE;
 684   } else {
 685     return JVMTI_ERROR_WRONG_PHASE;
 686   }
 687 
 688 } /* end AddToBootstrapClassLoaderSearch */
 689 
 690 
 691 // segment - pre-checked for null
 692 jvmtiError
 693 JvmtiEnv::AddToSystemClassLoaderSearch(const char* segment) {
 694   jvmtiPhase phase = get_phase();
 695 
 696   if (phase == JVMTI_PHASE_ONLOAD) {
 697     for (SystemProperty* p = Arguments::system_properties(); p != nullptr; p = p->next()) {
 698       if (strcmp("java.class.path", p->key()) == 0) {
 699         p->append_value(segment);
 700         break;
 701       }
 702     }
 703     return JVMTI_ERROR_NONE;
 704   } else if (phase == JVMTI_PHASE_LIVE) {
 705     // The phase is checked by the wrapper that called this function,
 706     // but this thread could be racing with the thread that is
 707     // terminating the VM so we check one more time.
 708     JavaThread* THREAD = JavaThread::current(); // For exception macros.
 709     HandleMark hm(THREAD);
 710 
 711     // create the zip entry (which will open the zip file and hence
 712     // check that the segment is indeed a zip file).
 713     ClassPathZipEntry* zip_entry = ClassLoader::create_class_path_zip_entry(segment, false);
 714     if (zip_entry == nullptr) {
 715       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 716     }
 717     delete zip_entry;   // no longer needed
 718 
 719     Handle loader(THREAD, SystemDictionary::java_system_loader());
 720 
 721     // need the path as java.lang.String
 722     Handle path = java_lang_String::create_from_platform_dependent_str(segment, THREAD);
 723     if (HAS_PENDING_EXCEPTION) {
 724       CLEAR_PENDING_EXCEPTION;
 725       return JVMTI_ERROR_INTERNAL;
 726     }
 727 
 728     // Invoke the appendToClassPathForInstrumentation method - if the method
 729     // is not found it means the loader doesn't support adding to the class path
 730     // in the live phase.
 731     {
 732       JavaValue res(T_VOID);
 733       JavaCalls::call_special(&res,
 734                               loader,
 735                               loader->klass(),
 736                               vmSymbols::appendToClassPathForInstrumentation_name(),
 737                               vmSymbols::appendToClassPathForInstrumentation_signature(),
 738                               path,
 739                               THREAD);
 740       if (HAS_PENDING_EXCEPTION) {
 741         Symbol* ex_name = PENDING_EXCEPTION->klass()->name();
 742         CLEAR_PENDING_EXCEPTION;
 743 
 744         if (ex_name == vmSymbols::java_lang_NoSuchMethodError()) {
 745           return JVMTI_ERROR_CLASS_LOADER_UNSUPPORTED;
 746         } else {
 747           return JVMTI_ERROR_INTERNAL;
 748         }
 749       }
 750     }
 751 
 752     return JVMTI_ERROR_NONE;
 753   } else {
 754     return JVMTI_ERROR_WRONG_PHASE;
 755   }
 756 } /* end AddToSystemClassLoaderSearch */
 757 
 758   //
 759   // General functions
 760   //
 761 
 762 // phase_ptr - pre-checked for null
 763 jvmtiError
 764 JvmtiEnv::GetPhase(jvmtiPhase* phase_ptr) {
 765   *phase_ptr = phase();
 766   return JVMTI_ERROR_NONE;
 767 } /* end GetPhase */
 768 
 769 
 770 jvmtiError
 771 JvmtiEnv::DisposeEnvironment() {
 772   dispose();
 773   return JVMTI_ERROR_NONE;
 774 } /* end DisposeEnvironment */
 775 
 776 
 777 // data - null is a valid value, must be checked
 778 jvmtiError
 779 JvmtiEnv::SetEnvironmentLocalStorage(const void* data) {
 780   set_env_local_storage(data);
 781   return JVMTI_ERROR_NONE;
 782 } /* end SetEnvironmentLocalStorage */
 783 
 784 
 785 // data_ptr - pre-checked for null
 786 jvmtiError
 787 JvmtiEnv::GetEnvironmentLocalStorage(void** data_ptr) {
 788   *data_ptr = (void*)get_env_local_storage();
 789   return JVMTI_ERROR_NONE;
 790 } /* end GetEnvironmentLocalStorage */
 791 
 792 // version_ptr - pre-checked for null
 793 jvmtiError
 794 JvmtiEnv::GetVersionNumber(jint* version_ptr) {
 795   *version_ptr = JVMTI_VERSION;
 796   return JVMTI_ERROR_NONE;
 797 } /* end GetVersionNumber */
 798 
 799 
 800 // name_ptr - pre-checked for null
 801 jvmtiError
 802 JvmtiEnv::GetErrorName(jvmtiError error, char** name_ptr) {
 803   if (error < JVMTI_ERROR_NONE || error > JVMTI_ERROR_MAX) {
 804     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 805   }
 806   const char *name = JvmtiUtil::error_name(error);
 807   if (name == nullptr) {
 808     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 809   }
 810   size_t len = strlen(name) + 1;
 811   jvmtiError err = allocate(len, (unsigned char**)name_ptr);
 812   if (err == JVMTI_ERROR_NONE) {
 813     memcpy(*name_ptr, name, len);
 814   }
 815   return err;
 816 } /* end GetErrorName */
 817 
 818 
 819 jvmtiError
 820 JvmtiEnv::SetVerboseFlag(jvmtiVerboseFlag flag, jboolean value) {
 821   LogLevelType level = value == 0 ? LogLevel::Off : LogLevel::Info;
 822   switch (flag) {
 823   case JVMTI_VERBOSE_OTHER:
 824     // ignore
 825     break;
 826   case JVMTI_VERBOSE_CLASS:
 827     LogConfiguration::configure_stdout(level, false, LOG_TAGS(class, unload));
 828     LogConfiguration::configure_stdout(level, false, LOG_TAGS(class, load));
 829     break;
 830   case JVMTI_VERBOSE_GC:
 831     LogConfiguration::configure_stdout(level, true, LOG_TAGS(gc));
 832     break;
 833   case JVMTI_VERBOSE_JNI:
 834     level = value == 0 ? LogLevel::Off : LogLevel::Debug;
 835     LogConfiguration::configure_stdout(level, true, LOG_TAGS(jni, resolve));
 836     break;
 837   default:
 838     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 839   };
 840   return JVMTI_ERROR_NONE;
 841 } /* end SetVerboseFlag */
 842 
 843 
 844 // format_ptr - pre-checked for null
 845 jvmtiError
 846 JvmtiEnv::GetJLocationFormat(jvmtiJlocationFormat* format_ptr) {
 847   *format_ptr = JVMTI_JLOCATION_JVMBCI;
 848   return JVMTI_ERROR_NONE;
 849 } /* end GetJLocationFormat */
 850 
 851   //
 852   // Thread functions
 853   //
 854 
 855 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
 856 // thread_state_ptr - pre-checked for null
 857 jvmtiError
 858 JvmtiEnv::GetThreadState(jthread thread, jint* thread_state_ptr) {
 859   JavaThread* current_thread = JavaThread::current();
 860   JvmtiVTMSTransitionDisabler disabler(thread);
 861   ThreadsListHandle tlh(current_thread);
 862 
 863   JavaThread* java_thread = nullptr;
 864   oop thread_oop = nullptr;
 865   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_oop);
 866   if (err != JVMTI_ERROR_NONE && err != JVMTI_ERROR_THREAD_NOT_ALIVE) {
 867     // We got an error code so we don't have a JavaThread*, but only
 868     // return an error from here if the error is not because the thread
 869     // is a virtual thread.
 870     return err;
 871   }
 872   *thread_state_ptr = JvmtiEnvBase::get_thread_or_vthread_state(thread_oop, java_thread);
 873   return JVMTI_ERROR_NONE;
 874 } /* end GetThreadState */
 875 
 876 
 877 // thread_ptr - pre-checked for null
 878 jvmtiError
 879 JvmtiEnv::GetCurrentThread(jthread* thread_ptr) {
 880   JavaThread* cur_thread = JavaThread::current();
 881   oop thread_oop = get_vthread_or_thread_oop(cur_thread);
 882 
 883   *thread_ptr = (jthread)JNIHandles::make_local(cur_thread, thread_oop);
 884   return JVMTI_ERROR_NONE;
 885 } /* end GetCurrentThread */
 886 
 887 
 888 // threads_count_ptr - pre-checked for null
 889 // threads_ptr - pre-checked for null
 890 jvmtiError
 891 JvmtiEnv::GetAllThreads(jint* threads_count_ptr, jthread** threads_ptr) {
 892   int nthreads        = 0;
 893   Handle *thread_objs = nullptr;
 894   Thread* current_thread = Thread::current();
 895   ResourceMark rm(current_thread);
 896   HandleMark hm(current_thread);
 897 
 898   // enumerate threads (including agent threads)
 899   ThreadsListEnumerator tle(current_thread, true);
 900   nthreads = tle.num_threads();
 901   *threads_count_ptr = nthreads;
 902 
 903   if (nthreads == 0) {
 904     *threads_ptr = nullptr;
 905     return JVMTI_ERROR_NONE;
 906   }
 907 
 908   thread_objs = NEW_RESOURCE_ARRAY(Handle, nthreads);
 909   NULL_CHECK(thread_objs, JVMTI_ERROR_OUT_OF_MEMORY);
 910 
 911   for (int i = 0; i < nthreads; i++) {
 912     thread_objs[i] = Handle(tle.get_threadObj(i));
 913   }
 914 
 915   jthread *jthreads  = new_jthreadArray(nthreads, thread_objs);
 916   NULL_CHECK(jthreads, JVMTI_ERROR_OUT_OF_MEMORY);
 917 
 918   *threads_ptr = jthreads;
 919   return JVMTI_ERROR_NONE;
 920 } /* end GetAllThreads */
 921 
 922 
 923 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
 924 jvmtiError
 925 JvmtiEnv::SuspendThread(jthread thread) {
 926   JavaThread* current = JavaThread::current();
 927   HandleMark hm(current);
 928   Handle self_tobj;
 929 
 930   jvmtiError err;
 931   {
 932     JvmtiVTMSTransitionDisabler disabler(true);
 933     ThreadsListHandle tlh(current);
 934     JavaThread* java_thread = nullptr;
 935     oop thread_oop = nullptr;
 936 
 937     err = get_threadOop_and_JavaThread(tlh.list(), thread, current, &java_thread, &thread_oop);
 938     if (err != JVMTI_ERROR_NONE) {
 939       return err;
 940     }
 941 
 942     // Do not use JvmtiVTMSTransitionDisabler in context of self suspend to avoid deadlocks.
 943     if (java_thread != current) {
 944       err = suspend_thread(thread_oop, java_thread, /* single_suspend */ true, nullptr);
 945       return err;
 946     }
 947     // protect thread_oop as a safepoint can be reached in disabler destructor
 948     self_tobj = Handle(current, thread_oop);
 949   }
 950   // Do self suspend for current JavaThread.
 951   err = suspend_thread(self_tobj(), current, /* single_suspend */ true, nullptr);
 952   return err;
 953 } /* end SuspendThread */
 954 
 955 
 956 // request_count - pre-checked to be greater than or equal to 0
 957 // request_list - pre-checked for null
 958 // results - pre-checked for null
 959 jvmtiError
 960 JvmtiEnv::SuspendThreadList(jint request_count, const jthread* request_list, jvmtiError* results) {
 961   JavaThread* current = JavaThread::current();
 962   HandleMark hm(current);
 963   Handle self_tobj;
 964   int self_idx = -1;
 965 
 966   {
 967     JvmtiVTMSTransitionDisabler disabler(true);
 968     ThreadsListHandle tlh(current);
 969 
 970     for (int i = 0; i < request_count; i++) {
 971       JavaThread *java_thread = nullptr;
 972       oop thread_oop = nullptr;
 973       jthread thread = request_list[i];
 974       jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
 975 
 976       if (thread_oop != nullptr &&
 977           java_lang_VirtualThread::is_instance(thread_oop) &&
 978           !JvmtiEnvBase::is_vthread_alive(thread_oop)) {
 979         err = JVMTI_ERROR_THREAD_NOT_ALIVE;
 980       }
 981       if (err != JVMTI_ERROR_NONE) {
 982         if (thread_oop == nullptr || err != JVMTI_ERROR_INVALID_THREAD) {
 983           results[i] = err;
 984           continue;
 985         }
 986       }
 987       if (java_thread == current) {
 988         self_idx = i;
 989         self_tobj = Handle(current, thread_oop);
 990         continue; // self suspend after all other suspends
 991       }
 992       results[i] = suspend_thread(thread_oop, java_thread, /* single_suspend */ true, nullptr);
 993     }
 994   }
 995   // Self suspend after all other suspends if necessary.
 996   // Do not use JvmtiVTMSTransitionDisabler in context of self suspend to avoid deadlocks.
 997   if (self_tobj() != nullptr) {
 998     // there should not be any error for current java_thread
 999     results[self_idx] = suspend_thread(self_tobj(), current, /* single_suspend */ true, nullptr);
1000   }
1001   // per-thread suspend results returned via results parameter
1002   return JVMTI_ERROR_NONE;
1003 } /* end SuspendThreadList */
1004 
1005 
1006 jvmtiError
1007 JvmtiEnv::SuspendAllVirtualThreads(jint except_count, const jthread* except_list) {
1008   if (get_capabilities()->can_support_virtual_threads == 0) {
1009     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
1010   }
1011   JavaThread* current = JavaThread::current();
1012   HandleMark hm(current);
1013   Handle self_tobj;
1014 
1015   {
1016     ResourceMark rm(current);
1017     JvmtiVTMSTransitionDisabler disabler(true);
1018     ThreadsListHandle tlh(current);
1019     GrowableArray<jthread>* elist = new GrowableArray<jthread>(except_count);
1020 
1021     jvmtiError err = JvmtiEnvBase::check_thread_list(except_count, except_list);
1022     if (err != JVMTI_ERROR_NONE) {
1023       return err;
1024     }
1025 
1026     // Collect threads from except_list for which resumed status must be restored (only for VirtualThread case)
1027     for (int idx = 0; idx < except_count; idx++) {
1028       jthread thread = except_list[idx];
1029       oop thread_oop = JNIHandles::resolve_external_guard(thread);
1030       if (java_lang_VirtualThread::is_instance(thread_oop) && !JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1031           // is not suspended, so its resumed status must be restored
1032           elist->append(except_list[idx]);
1033       }
1034     }
1035 
1036     for (JavaThreadIteratorWithHandle jtiwh; JavaThread *java_thread = jtiwh.next(); ) {
1037       oop vt_oop = java_thread->jvmti_vthread();
1038       if (!java_thread->is_exiting() &&
1039           !java_thread->is_jvmti_agent_thread() &&
1040           !java_thread->is_hidden_from_external_view() &&
1041           vt_oop != nullptr &&
1042           ((java_lang_VirtualThread::is_instance(vt_oop) &&
1043             JvmtiEnvBase::is_vthread_alive(vt_oop) &&
1044             !JvmtiVTSuspender::is_vthread_suspended(vt_oop)) ||
1045             (vt_oop->is_a(vmClasses::BoundVirtualThread_klass()) && !java_thread->is_suspended())) &&
1046           !is_in_thread_list(except_count, except_list, vt_oop)
1047          ) {
1048         if (java_thread == current) {
1049           self_tobj = Handle(current, vt_oop);
1050           continue; // self suspend after all other suspends
1051         }
1052         suspend_thread(vt_oop, java_thread, /* single_suspend */ false, nullptr);
1053       }
1054     }
1055     JvmtiVTSuspender::register_all_vthreads_suspend();
1056 
1057     // Restore resumed state for threads from except list that were not suspended before.
1058     for (int idx = 0; idx < elist->length(); idx++) {
1059       jthread thread = elist->at(idx);
1060       oop thread_oop = JNIHandles::resolve_external_guard(thread);
1061       if (JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1062         JvmtiVTSuspender::register_vthread_resume(thread_oop);
1063       }
1064     }
1065   }
1066   // Self suspend after all other suspends if necessary.
1067   // Do not use JvmtiVTMSTransitionDisabler in context of self suspend to avoid deadlocks.
1068   if (self_tobj() != nullptr) {
1069     suspend_thread(self_tobj(), current, /* single_suspend */ false, nullptr);
1070   }
1071   return JVMTI_ERROR_NONE;
1072 } /* end SuspendAllVirtualThreads */
1073 
1074 
1075 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1076 jvmtiError
1077 JvmtiEnv::ResumeThread(jthread thread) {
1078   JvmtiVTMSTransitionDisabler disabler(true);
1079   JavaThread* current = JavaThread::current();
1080   ThreadsListHandle tlh(current);
1081 
1082   JavaThread* java_thread = nullptr;
1083   oop thread_oop = nullptr;
1084   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current, &java_thread, &thread_oop);
1085   if (err != JVMTI_ERROR_NONE) {
1086     return err;
1087   }
1088   err = resume_thread(thread_oop, java_thread, /* single_resume */ true);
1089   return err;
1090 } /* end ResumeThread */
1091 
1092 
1093 // request_count - pre-checked to be greater than or equal to 0
1094 // request_list - pre-checked for null
1095 // results - pre-checked for null
1096 jvmtiError
1097 JvmtiEnv::ResumeThreadList(jint request_count, const jthread* request_list, jvmtiError* results) {
1098   oop thread_oop = nullptr;
1099   JavaThread* java_thread = nullptr;
1100   JvmtiVTMSTransitionDisabler disabler(true);
1101   ThreadsListHandle tlh;
1102 
1103   for (int i = 0; i < request_count; i++) {
1104     jthread thread = request_list[i];
1105     jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1106 
1107     if (thread_oop != nullptr &&
1108         java_lang_VirtualThread::is_instance(thread_oop) &&
1109         !JvmtiEnvBase::is_vthread_alive(thread_oop)) {
1110       err = JVMTI_ERROR_THREAD_NOT_ALIVE;
1111     }
1112     if (err != JVMTI_ERROR_NONE) {
1113       if (thread_oop == nullptr || err != JVMTI_ERROR_INVALID_THREAD) {
1114         results[i] = err;
1115         continue;
1116       }
1117     }
1118     results[i] = resume_thread(thread_oop, java_thread, /* single_resume */ true);
1119   }
1120   // per-thread resume results returned via results parameter
1121   return JVMTI_ERROR_NONE;
1122 } /* end ResumeThreadList */
1123 
1124 
1125 jvmtiError
1126 JvmtiEnv::ResumeAllVirtualThreads(jint except_count, const jthread* except_list) {
1127   if (get_capabilities()->can_support_virtual_threads == 0) {
1128     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
1129   }
1130   jvmtiError err = JvmtiEnvBase::check_thread_list(except_count, except_list);
1131   if (err != JVMTI_ERROR_NONE) {
1132     return err;
1133   }
1134   ResourceMark rm;
1135   JvmtiVTMSTransitionDisabler disabler(true);
1136   GrowableArray<jthread>* elist = new GrowableArray<jthread>(except_count);
1137 
1138   // Collect threads from except_list for which suspended status must be restored (only for VirtualThread case)
1139   for (int idx = 0; idx < except_count; idx++) {
1140     jthread thread = except_list[idx];
1141     oop thread_oop = JNIHandles::resolve_external_guard(thread);
1142     if (java_lang_VirtualThread::is_instance(thread_oop) && JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1143       // is suspended, so its suspended status must be restored
1144       elist->append(except_list[idx]);
1145     }
1146   }
1147 
1148   for (JavaThreadIteratorWithHandle jtiwh; JavaThread *java_thread = jtiwh.next(); ) {
1149     oop vt_oop = java_thread->jvmti_vthread();
1150     if (!java_thread->is_exiting() &&
1151         !java_thread->is_jvmti_agent_thread() &&
1152         !java_thread->is_hidden_from_external_view() &&
1153         vt_oop != nullptr &&
1154         ((java_lang_VirtualThread::is_instance(vt_oop) &&
1155           JvmtiEnvBase::is_vthread_alive(vt_oop) &&
1156           JvmtiVTSuspender::is_vthread_suspended(vt_oop)) ||
1157           (vt_oop->is_a(vmClasses::BoundVirtualThread_klass()) && java_thread->is_suspended())) &&
1158         !is_in_thread_list(except_count, except_list, vt_oop)
1159     ) {
1160       resume_thread(vt_oop, java_thread, /* single_resume */ false);
1161     }
1162   }
1163   JvmtiVTSuspender::register_all_vthreads_resume();
1164 
1165   // Restore suspended state for threads from except list that were suspended before.
1166   for (int idx = 0; idx < elist->length(); idx++) {
1167     jthread thread = elist->at(idx);
1168     oop thread_oop = JNIHandles::resolve_external_guard(thread);
1169     if (!JvmtiVTSuspender::is_vthread_suspended(thread_oop)) {
1170       JvmtiVTSuspender::register_vthread_suspend(thread_oop);
1171     }
1172   }
1173   return JVMTI_ERROR_NONE;
1174 } /* end ResumeAllVirtualThreads */
1175 
1176 
1177 jvmtiError
1178 JvmtiEnv::StopThread(jthread thread, jobject exception) {
1179   JavaThread* current_thread = JavaThread::current();
1180 
1181   JvmtiVTMSTransitionDisabler disabler(thread);
1182   ThreadsListHandle tlh(current_thread);
1183   JavaThread* java_thread = nullptr;
1184   oop thread_oop = nullptr;
1185 
1186   NULL_CHECK(thread, JVMTI_ERROR_INVALID_THREAD);
1187 
1188   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_oop);
1189 
1190   bool is_virtual = thread_oop != nullptr && thread_oop->is_a(vmClasses::BaseVirtualThread_klass());
1191 
1192   if (is_virtual && !is_JavaThread_current(java_thread, thread_oop)) {
1193     if (!is_vthread_suspended(thread_oop, java_thread)) {
1194       return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
1195     }
1196     if (java_thread == nullptr) { // unmounted virtual thread
1197       return JVMTI_ERROR_OPAQUE_FRAME;
1198     }
1199   }
1200   if (err != JVMTI_ERROR_NONE) {
1201     return err;
1202   }
1203   oop e = JNIHandles::resolve_external_guard(exception);
1204   NULL_CHECK(e, JVMTI_ERROR_NULL_POINTER);
1205 
1206   JavaThread::send_async_exception(java_thread, e);
1207 
1208   return JVMTI_ERROR_NONE;
1209 
1210 } /* end StopThread */
1211 
1212 
1213 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1214 jvmtiError
1215 JvmtiEnv::InterruptThread(jthread thread) {
1216   JavaThread* current_thread  = JavaThread::current();
1217   HandleMark hm(current_thread);
1218 
1219   JvmtiVTMSTransitionDisabler disabler(thread);
1220   ThreadsListHandle tlh(current_thread);
1221 
1222   JavaThread* java_thread = nullptr;
1223   oop thread_obj = nullptr;
1224   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
1225   if (err != JVMTI_ERROR_NONE) {
1226     return err;
1227   }
1228 
1229   if (java_lang_VirtualThread::is_instance(thread_obj)) {
1230     // For virtual threads we have to call into Java to interrupt:
1231     Handle obj(current_thread, thread_obj);
1232     JavaValue result(T_VOID);
1233     JavaCalls::call_virtual(&result,
1234                             obj,
1235                             vmClasses::Thread_klass(),
1236                             vmSymbols::interrupt_method_name(),
1237                             vmSymbols::void_method_signature(),
1238                             current_thread);
1239 
1240     return JVMTI_ERROR_NONE;
1241   }
1242 
1243   // Really this should be a Java call to Thread.interrupt to ensure the same
1244   // semantics, however historically this has not been done for some reason.
1245   // So we continue with that (which means we don't interact with any Java-level
1246   // Interruptible object) but we must set the Java-level interrupted state.
1247   java_lang_Thread::set_interrupted(thread_obj, true);
1248   java_thread->interrupt();
1249 
1250   return JVMTI_ERROR_NONE;
1251 } /* end InterruptThread */
1252 
1253 
1254 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1255 // info_ptr - pre-checked for null
1256 jvmtiError
1257 JvmtiEnv::GetThreadInfo(jthread thread, jvmtiThreadInfo* info_ptr) {
1258   JavaThread* current_thread = JavaThread::current();
1259   ResourceMark rm(current_thread);
1260   HandleMark hm(current_thread);
1261   JavaThread* java_thread = nullptr;
1262   oop thread_oop = nullptr;
1263 
1264   JvmtiVTMSTransitionDisabler disabler(thread);
1265   ThreadsListHandle tlh(current_thread);
1266 
1267   // if thread is null the current thread is used
1268   if (thread == nullptr) {
1269     java_thread = JavaThread::current();
1270     thread_oop = get_vthread_or_thread_oop(java_thread);
1271     if (thread_oop == nullptr || !thread_oop->is_a(vmClasses::Thread_klass())) {
1272       return JVMTI_ERROR_INVALID_THREAD;
1273     }
1274   } else {
1275     jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1276     if (err != JVMTI_ERROR_NONE) {
1277       // We got an error code so we don't have a JavaThread *, but
1278       // only return an error from here if we didn't get a valid
1279       // thread_oop.
1280       // In the virtual thread case the cv_external_thread_to_JavaThread is expected to correctly set
1281       // the thread_oop and return JVMTI_ERROR_INVALID_THREAD which we ignore here.
1282       if (thread_oop == nullptr) {
1283         return err;
1284       }
1285     }
1286   }
1287   // We have a valid thread_oop so we can return some thread info.
1288 
1289   Handle thread_obj(current_thread, thread_oop);
1290   Handle name;
1291   ThreadPriority priority;
1292   Handle     thread_group;
1293   Handle context_class_loader;
1294   bool          is_daemon;
1295 
1296   name = Handle(current_thread, java_lang_Thread::name(thread_obj()));
1297 
1298   if (java_lang_VirtualThread::is_instance(thread_obj())) {
1299     priority = (ThreadPriority)JVMTI_THREAD_NORM_PRIORITY;
1300     is_daemon = true;
1301     if (java_lang_VirtualThread::state(thread_obj()) == java_lang_VirtualThread::TERMINATED) {
1302       thread_group = Handle(current_thread, nullptr);
1303     } else {
1304       thread_group = Handle(current_thread, java_lang_Thread_Constants::get_VTHREAD_GROUP());
1305     }
1306   } else {
1307     priority = java_lang_Thread::priority(thread_obj());
1308     is_daemon = java_lang_Thread::is_daemon(thread_obj());
1309     if (java_lang_Thread::get_thread_status(thread_obj()) == JavaThreadStatus::TERMINATED) {
1310       thread_group = Handle(current_thread, nullptr);
1311     } else {
1312       thread_group = Handle(current_thread, java_lang_Thread::threadGroup(thread_obj()));
1313     }
1314   }
1315 
1316   oop loader = java_lang_Thread::context_class_loader(thread_obj());
1317   context_class_loader = Handle(current_thread, loader);
1318 
1319   { const char *n;
1320 
1321     if (name() != nullptr) {
1322       n = java_lang_String::as_utf8_string(name());
1323     } else {
1324       int utf8_length = 0;
1325       n = UNICODE::as_utf8((jchar*) nullptr, utf8_length);
1326     }
1327 
1328     info_ptr->name = (char *) jvmtiMalloc(strlen(n)+1);
1329     if (info_ptr->name == nullptr)
1330       return JVMTI_ERROR_OUT_OF_MEMORY;
1331 
1332     strcpy(info_ptr->name, n);
1333   }
1334   info_ptr->is_daemon = is_daemon;
1335   info_ptr->priority  = priority;
1336 
1337   info_ptr->context_class_loader = (context_class_loader.is_null()) ? nullptr :
1338                                     jni_reference(context_class_loader);
1339   info_ptr->thread_group = jni_reference(thread_group);
1340 
1341   return JVMTI_ERROR_NONE;
1342 } /* end GetThreadInfo */
1343 
1344 
1345 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1346 // owned_monitor_count_ptr - pre-checked for null
1347 // owned_monitors_ptr - pre-checked for null
1348 jvmtiError
1349 JvmtiEnv::GetOwnedMonitorInfo(jthread thread, jint* owned_monitor_count_ptr, jobject** owned_monitors_ptr) {
1350   JavaThread* calling_thread = JavaThread::current();
1351   HandleMark hm(calling_thread);
1352 
1353   // growable array of jvmti monitors info on the C-heap
1354   GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list =
1355       new (mtServiceability) GrowableArray<jvmtiMonitorStackDepthInfo*>(1, mtServiceability);
1356 
1357   JvmtiVTMSTransitionDisabler disabler(thread);
1358   ThreadsListHandle tlh(calling_thread);
1359 
1360   JavaThread* java_thread = nullptr;
1361   oop thread_oop = nullptr;
1362   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, calling_thread, &java_thread, &thread_oop);
1363   if (err != JVMTI_ERROR_NONE) {
1364     delete owned_monitors_list;
1365     return err;
1366   }
1367 
1368   if (java_thread != nullptr) {
1369     Handle thread_handle(calling_thread, thread_oop);
1370     EscapeBarrier eb(true, calling_thread, java_thread);
1371     if (!eb.deoptimize_objects(MaxJavaStackTraceDepth)) {
1372       delete owned_monitors_list;
1373       return JVMTI_ERROR_OUT_OF_MEMORY;
1374     }
1375     // get owned monitors info with handshake
1376     GetOwnedMonitorInfoClosure op(this, calling_thread, owned_monitors_list);
1377     JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1378     err = op.result();
1379   }
1380 
1381   jint owned_monitor_count = owned_monitors_list->length();
1382   if (err == JVMTI_ERROR_NONE) {
1383     if ((err = allocate(owned_monitor_count * sizeof(jobject *),
1384                       (unsigned char**)owned_monitors_ptr)) == JVMTI_ERROR_NONE) {
1385       // copy into the returned array
1386       for (int i = 0; i < owned_monitor_count; i++) {
1387         (*owned_monitors_ptr)[i] =
1388           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->monitor;
1389       }
1390       *owned_monitor_count_ptr = owned_monitor_count;
1391     }
1392   }
1393   // clean up.
1394   for (int i = 0; i < owned_monitor_count; i++) {
1395     deallocate((unsigned char*)owned_monitors_list->at(i));
1396   }
1397   delete owned_monitors_list;
1398 
1399   return err;
1400 } /* end GetOwnedMonitorInfo */
1401 
1402 
1403 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1404 // monitor_info_count_ptr - pre-checked for null
1405 // monitor_info_ptr - pre-checked for null
1406 jvmtiError
1407 JvmtiEnv::GetOwnedMonitorStackDepthInfo(jthread thread, jint* monitor_info_count_ptr, jvmtiMonitorStackDepthInfo** monitor_info_ptr) {
1408   JavaThread* calling_thread = JavaThread::current();
1409   HandleMark hm(calling_thread);
1410 
1411   // growable array of jvmti monitors info on the C-heap
1412   GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list =
1413          new (mtServiceability) GrowableArray<jvmtiMonitorStackDepthInfo*>(1, mtServiceability);
1414 
1415   JvmtiVTMSTransitionDisabler disabler(thread);
1416   ThreadsListHandle tlh(calling_thread);
1417 
1418   JavaThread* java_thread = nullptr;
1419   oop thread_oop = nullptr;
1420   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, calling_thread, &java_thread, &thread_oop);
1421   if (err != JVMTI_ERROR_NONE) {
1422     delete owned_monitors_list;
1423     return err;
1424   }
1425 
1426   if (java_thread != nullptr) {
1427     Handle thread_handle(calling_thread, thread_oop);
1428     EscapeBarrier eb(true, calling_thread, java_thread);
1429     if (!eb.deoptimize_objects(MaxJavaStackTraceDepth)) {
1430       delete owned_monitors_list;
1431       return JVMTI_ERROR_OUT_OF_MEMORY;
1432     }
1433     // get owned monitors info with handshake
1434     GetOwnedMonitorInfoClosure op(this, calling_thread, owned_monitors_list);
1435     JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1436     err = op.result();
1437   }
1438 
1439   jint owned_monitor_count = owned_monitors_list->length();
1440   if (err == JVMTI_ERROR_NONE) {
1441     if ((err = allocate(owned_monitor_count * sizeof(jvmtiMonitorStackDepthInfo),
1442                         (unsigned char**)monitor_info_ptr)) == JVMTI_ERROR_NONE) {
1443       // copy to output array.
1444       for (int i = 0; i < owned_monitor_count; i++) {
1445         (*monitor_info_ptr)[i].monitor =
1446           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->monitor;
1447         (*monitor_info_ptr)[i].stack_depth =
1448           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->stack_depth;
1449       }
1450     }
1451     *monitor_info_count_ptr = owned_monitor_count;
1452   }
1453 
1454   // clean up.
1455   for (int i = 0; i < owned_monitor_count; i++) {
1456     deallocate((unsigned char*)owned_monitors_list->at(i));
1457   }
1458   delete owned_monitors_list;
1459 
1460   return err;
1461 } /* end GetOwnedMonitorStackDepthInfo */
1462 
1463 
1464 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1465 // monitor_ptr - pre-checked for null
1466 jvmtiError
1467 JvmtiEnv::GetCurrentContendedMonitor(jthread thread, jobject* monitor_ptr) {
1468   JavaThread* current = JavaThread::current();
1469 
1470   *monitor_ptr = nullptr;
1471 
1472   // get contended monitor information with handshake
1473   GetCurrentContendedMonitorClosure op(this, current, monitor_ptr);
1474   JvmtiHandshake::execute(&op, thread);
1475   return op.result();
1476 } /* end GetCurrentContendedMonitor */
1477 
1478 
1479 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1480 // proc - pre-checked for null
1481 // arg - null is a valid value, must be checked
1482 jvmtiError
1483 JvmtiEnv::RunAgentThread(jthread thread, jvmtiStartFunction proc, const void* arg, jint priority) {
1484   JavaThread* current_thread = JavaThread::current();
1485 
1486   JavaThread* java_thread = nullptr;
1487   oop thread_oop = nullptr;
1488   ThreadsListHandle tlh(current_thread);
1489   jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1490   if (err != JVMTI_ERROR_NONE) {
1491     // We got an error code so we don't have a JavaThread *, but
1492     // only return an error from here if we didn't get a valid
1493     // thread_oop.
1494     if (thread_oop == nullptr) {
1495       return err;
1496     }
1497     // We have a valid thread_oop.
1498   }
1499 
1500   if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
1501     // No support for virtual threads.
1502     return JVMTI_ERROR_UNSUPPORTED_OPERATION;
1503   }
1504   if (java_thread != nullptr) {
1505     // 'thread' refers to an existing JavaThread.
1506     return JVMTI_ERROR_INVALID_THREAD;
1507   }
1508 
1509   if (priority < JVMTI_THREAD_MIN_PRIORITY || priority > JVMTI_THREAD_MAX_PRIORITY) {
1510     return JVMTI_ERROR_INVALID_PRIORITY;
1511   }
1512 
1513   Handle thread_hndl(current_thread, thread_oop);
1514 
1515   JvmtiAgentThread* new_thread = new JvmtiAgentThread(this, proc, arg);
1516 
1517   // At this point it may be possible that no osthread was created for the
1518   // JavaThread due to lack of resources.
1519   if (new_thread->osthread() == nullptr) {
1520     // The new thread is not known to Thread-SMR yet so we can just delete.
1521     delete new_thread;
1522     return JVMTI_ERROR_OUT_OF_MEMORY;
1523   }
1524 
1525   JavaThread::start_internal_daemon(current_thread, new_thread, thread_hndl,
1526                                     (ThreadPriority)priority);
1527 
1528   return JVMTI_ERROR_NONE;
1529 } /* end RunAgentThread */
1530 
1531   //
1532   // Thread Group functions
1533   //
1534 
1535 // group_count_ptr - pre-checked for null
1536 // groups_ptr - pre-checked for null
1537 jvmtiError
1538 JvmtiEnv::GetTopThreadGroups(jint* group_count_ptr, jthreadGroup** groups_ptr) {
1539   JavaThread* current_thread = JavaThread::current();
1540 
1541   // Only one top level thread group now.
1542   *group_count_ptr = 1;
1543 
1544   // Allocate memory to store global-refs to the thread groups.
1545   // Assume this area is freed by caller.
1546   *groups_ptr = (jthreadGroup *) jvmtiMalloc((sizeof(jthreadGroup)) * (*group_count_ptr));
1547 
1548   NULL_CHECK(*groups_ptr, JVMTI_ERROR_OUT_OF_MEMORY);
1549 
1550   // Convert oop to Handle, then convert Handle to global-ref.
1551   {
1552     HandleMark hm(current_thread);
1553     Handle system_thread_group(current_thread, Universe::system_thread_group());
1554     *groups_ptr[0] = jni_reference(system_thread_group);
1555   }
1556 
1557   return JVMTI_ERROR_NONE;
1558 } /* end GetTopThreadGroups */
1559 
1560 
1561 // info_ptr - pre-checked for null
1562 jvmtiError
1563 JvmtiEnv::GetThreadGroupInfo(jthreadGroup group, jvmtiThreadGroupInfo* info_ptr) {
1564   Thread* current_thread = Thread::current();
1565   ResourceMark rm(current_thread);
1566   HandleMark hm(current_thread);
1567 
1568   Handle group_obj (current_thread, JNIHandles::resolve_external_guard(group));
1569   NULL_CHECK(group_obj(), JVMTI_ERROR_INVALID_THREAD_GROUP);
1570 
1571   const char* name;
1572   Handle parent_group;
1573   bool is_daemon;
1574   ThreadPriority max_priority;
1575 
1576   name         = java_lang_ThreadGroup::name(group_obj());
1577   parent_group = Handle(current_thread, java_lang_ThreadGroup::parent(group_obj()));
1578   is_daemon    = java_lang_ThreadGroup::is_daemon(group_obj());
1579   max_priority = java_lang_ThreadGroup::maxPriority(group_obj());
1580 
1581   info_ptr->is_daemon    = is_daemon;
1582   info_ptr->max_priority = max_priority;
1583   info_ptr->parent       = jni_reference(parent_group);
1584 
1585   if (name != nullptr) {
1586     info_ptr->name = (char*)jvmtiMalloc(strlen(name)+1);
1587     NULL_CHECK(info_ptr->name, JVMTI_ERROR_OUT_OF_MEMORY);
1588     strcpy(info_ptr->name, name);
1589   } else {
1590     info_ptr->name = nullptr;
1591   }
1592 
1593   return JVMTI_ERROR_NONE;
1594 } /* end GetThreadGroupInfo */
1595 
1596 // thread_count_ptr - pre-checked for null
1597 // threads_ptr - pre-checked for null
1598 // group_count_ptr - pre-checked for null
1599 // groups_ptr - pre-checked for null
1600 jvmtiError
1601 JvmtiEnv::GetThreadGroupChildren(jthreadGroup group, jint* thread_count_ptr, jthread** threads_ptr, jint* group_count_ptr, jthreadGroup** groups_ptr) {
1602   jvmtiError err;
1603   JavaThread* current_thread = JavaThread::current();
1604   oop group_obj = JNIHandles::resolve_external_guard(group);
1605   NULL_CHECK(group_obj, JVMTI_ERROR_INVALID_THREAD_GROUP);
1606 
1607   Handle *thread_objs = nullptr;
1608   objArrayHandle group_objs;
1609   jint nthreads = 0;
1610   jint ngroups = 0;
1611   int hidden_threads = 0;
1612 
1613   ResourceMark rm(current_thread);
1614   HandleMark hm(current_thread);
1615 
1616   Handle group_hdl(current_thread, group_obj);
1617 
1618   err = get_live_threads(current_thread, group_hdl, &nthreads, &thread_objs);
1619   if (err != JVMTI_ERROR_NONE) {
1620     return err;
1621   }
1622   err = get_subgroups(current_thread, group_hdl, &ngroups, &group_objs);
1623   if (err != JVMTI_ERROR_NONE) {
1624     return err;
1625   }
1626 
1627   *group_count_ptr  = ngroups;
1628   *thread_count_ptr = nthreads;
1629   *threads_ptr     = new_jthreadArray(nthreads, thread_objs);
1630   *groups_ptr      = new_jthreadGroupArray(ngroups, group_objs);
1631   if (nthreads > 0 && *threads_ptr == nullptr) {
1632     return JVMTI_ERROR_OUT_OF_MEMORY;
1633   }
1634   if (ngroups > 0 && *groups_ptr == nullptr) {
1635     return JVMTI_ERROR_OUT_OF_MEMORY;
1636   }
1637 
1638   return JVMTI_ERROR_NONE;
1639 } /* end GetThreadGroupChildren */
1640 
1641 
1642   //
1643   // Stack Frame functions
1644   //
1645 
1646 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1647 // max_frame_count - pre-checked to be greater than or equal to 0
1648 // frame_buffer - pre-checked for null
1649 // count_ptr - pre-checked for null
1650 jvmtiError
1651 JvmtiEnv::GetStackTrace(jthread thread, jint start_depth, jint max_frame_count, jvmtiFrameInfo* frame_buffer, jint* count_ptr) {
1652   GetStackTraceClosure op(this, start_depth, max_frame_count, frame_buffer, count_ptr);
1653   JvmtiHandshake::execute(&op, thread);
1654   return op.result();
1655 } /* end GetStackTrace */
1656 
1657 
1658 // max_frame_count - pre-checked to be greater than or equal to 0
1659 // stack_info_ptr - pre-checked for null
1660 // thread_count_ptr - pre-checked for null
1661 jvmtiError
1662 JvmtiEnv::GetAllStackTraces(jint max_frame_count, jvmtiStackInfo** stack_info_ptr, jint* thread_count_ptr) {
1663   jvmtiError err = JVMTI_ERROR_NONE;
1664   JavaThread* calling_thread = JavaThread::current();
1665 
1666   // JVMTI get stack traces at safepoint.
1667   VM_GetAllStackTraces op(this, calling_thread, max_frame_count);
1668   VMThread::execute(&op);
1669   *thread_count_ptr = op.final_thread_count();
1670   *stack_info_ptr = op.stack_info();
1671   err = op.result();
1672   return err;
1673 } /* end GetAllStackTraces */
1674 
1675 
1676 // thread_count - pre-checked to be greater than or equal to 0
1677 // thread_list - pre-checked for null
1678 // max_frame_count - pre-checked to be greater than or equal to 0
1679 // stack_info_ptr - pre-checked for null
1680 jvmtiError
1681 JvmtiEnv::GetThreadListStackTraces(jint thread_count, const jthread* thread_list, jint max_frame_count, jvmtiStackInfo** stack_info_ptr) {
1682   jvmtiError err = JVMTI_ERROR_NONE;
1683 
1684   if (thread_count == 1) {
1685     // Use direct handshake if we need to get only one stack trace.
1686     JavaThread *current_thread = JavaThread::current();
1687 
1688     jthread thread = thread_list[0];
1689 
1690     GetSingleStackTraceClosure op(this, current_thread, thread, max_frame_count);
1691     JvmtiHandshake::execute(&op, thread);
1692     err = op.result();
1693     if (err == JVMTI_ERROR_NONE) {
1694       *stack_info_ptr = op.stack_info();
1695     }
1696   } else {
1697     JvmtiVTMSTransitionDisabler disabler;
1698 
1699     // JVMTI get stack traces at safepoint.
1700     VM_GetThreadListStackTraces op(this, thread_count, thread_list, max_frame_count);
1701     VMThread::execute(&op);
1702     err = op.result();
1703     if (err == JVMTI_ERROR_NONE) {
1704       *stack_info_ptr = op.stack_info();
1705     }
1706   }
1707   return err;
1708 } /* end GetThreadListStackTraces */
1709 
1710 
1711 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1712 // count_ptr - pre-checked for null
1713 jvmtiError
1714 JvmtiEnv::GetFrameCount(jthread thread, jint* count_ptr) {
1715   GetFrameCountClosure op(this, count_ptr);
1716   JvmtiHandshake::execute(&op, thread);
1717   return op.result();
1718 } /* end GetFrameCount */
1719 
1720 
1721 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1722 jvmtiError
1723 JvmtiEnv::PopFrame(jthread thread) {
1724   JavaThread* current_thread = JavaThread::current();
1725   HandleMark hm(current_thread);
1726 
1727   if (thread == nullptr) {
1728     return JVMTI_ERROR_INVALID_THREAD;
1729   }
1730   JvmtiVTMSTransitionDisabler disabler(thread);
1731   ThreadsListHandle tlh(current_thread);
1732 
1733   JavaThread* java_thread = nullptr;
1734   oop thread_obj = nullptr;
1735   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
1736   Handle thread_handle(current_thread, thread_obj);
1737 
1738   if (err != JVMTI_ERROR_NONE) {
1739     return err;
1740   }
1741   bool self = java_thread == current_thread;
1742 
1743   err = check_non_suspended_or_opaque_frame(java_thread, thread_obj, self);
1744   if (err != JVMTI_ERROR_NONE) {
1745     return err;
1746   }
1747 
1748   // retrieve or create the state
1749   JvmtiThreadState* state = JvmtiThreadState::state_for(java_thread);
1750   if (state == nullptr) {
1751     return JVMTI_ERROR_THREAD_NOT_ALIVE;
1752   }
1753 
1754   // Eagerly reallocate scalar replaced objects.
1755   EscapeBarrier eb(true, current_thread, java_thread);
1756   if (!eb.deoptimize_objects(1)) {
1757     // Reallocation of scalar replaced objects failed -> return with error
1758     return JVMTI_ERROR_OUT_OF_MEMORY;
1759   }
1760 
1761   MutexLocker mu(JvmtiThreadState_lock);
1762   UpdateForPopTopFrameClosure op(state);
1763   JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1764   return op.result();
1765 } /* end PopFrame */
1766 
1767 
1768 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1769 // depth - pre-checked as non-negative
1770 // method_ptr - pre-checked for null
1771 // location_ptr - pre-checked for null
1772 jvmtiError
1773 JvmtiEnv::GetFrameLocation(jthread thread, jint depth, jmethodID* method_ptr, jlocation* location_ptr) {
1774   GetFrameLocationClosure op(this, depth, method_ptr, location_ptr);
1775   JvmtiHandshake::execute(&op, thread);
1776   return op.result();
1777 } /* end GetFrameLocation */
1778 
1779 
1780 // Threads_lock NOT held, java_thread not protected by lock
1781 // depth - pre-checked as non-negative
1782 jvmtiError
1783 JvmtiEnv::NotifyFramePop(jthread thread, jint depth) {
1784   ResourceMark rm;
1785   JvmtiVTMSTransitionDisabler disabler(thread);
1786   JavaThread* current = JavaThread::current();
1787   ThreadsListHandle tlh(current);
1788 
1789   JavaThread* java_thread = nullptr;
1790   oop thread_obj = nullptr;
1791   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current, &java_thread, &thread_obj);
1792   if (err != JVMTI_ERROR_NONE) {
1793     return err;
1794   }
1795 
1796   HandleMark hm(current);
1797   Handle thread_handle(current, thread_obj);
1798   JvmtiThreadState *state = JvmtiThreadState::state_for(java_thread, thread_handle);
1799   if (state == nullptr) {
1800     return JVMTI_ERROR_THREAD_NOT_ALIVE;
1801   }
1802 
1803   SetFramePopClosure op(this, state, depth);
1804   MutexLocker mu(current, JvmtiThreadState_lock);
1805   JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1806   return op.result();
1807 } /* end NotifyFramePop */
1808 
1809 
1810   //
1811   // Force Early Return functions
1812   //
1813 
1814 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1815 jvmtiError
1816 JvmtiEnv::ForceEarlyReturnObject(jthread thread, jobject value) {
1817   jvalue val;
1818   val.l = value;
1819   return force_early_return(thread, val, atos);
1820 } /* end ForceEarlyReturnObject */
1821 
1822 
1823 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1824 jvmtiError
1825 JvmtiEnv::ForceEarlyReturnInt(jthread thread, jint value) {
1826   jvalue val;
1827   val.i = value;
1828   return force_early_return(thread, val, itos);
1829 } /* end ForceEarlyReturnInt */
1830 
1831 
1832 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1833 jvmtiError
1834 JvmtiEnv::ForceEarlyReturnLong(jthread thread, jlong value) {
1835   jvalue val;
1836   val.j = value;
1837   return force_early_return(thread, val, ltos);
1838 } /* end ForceEarlyReturnLong */
1839 
1840 
1841 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1842 jvmtiError
1843 JvmtiEnv::ForceEarlyReturnFloat(jthread thread, jfloat value) {
1844   jvalue val;
1845   val.f = value;
1846   return force_early_return(thread, val, ftos);
1847 } /* end ForceEarlyReturnFloat */
1848 
1849 
1850 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1851 jvmtiError
1852 JvmtiEnv::ForceEarlyReturnDouble(jthread thread, jdouble value) {
1853   jvalue val;
1854   val.d = value;
1855   return force_early_return(thread, val, dtos);
1856 } /* end ForceEarlyReturnDouble */
1857 
1858 
1859 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1860 jvmtiError
1861 JvmtiEnv::ForceEarlyReturnVoid(jthread thread) {
1862   jvalue val;
1863   val.j = 0L;
1864   return force_early_return(thread, val, vtos);
1865 } /* end ForceEarlyReturnVoid */
1866 
1867 
1868   //
1869   // Heap functions
1870   //
1871 
1872 // klass - null is a valid value, must be checked
1873 // initial_object - null is a valid value, must be checked
1874 // callbacks - pre-checked for null
1875 // user_data - null is a valid value, must be checked
1876 jvmtiError
1877 JvmtiEnv::FollowReferences(jint heap_filter, jclass klass, jobject initial_object, const jvmtiHeapCallbacks* callbacks, const void* user_data) {
1878   // check klass if provided
1879   Klass* k = nullptr;
1880   if (klass != nullptr) {
1881     oop k_mirror = JNIHandles::resolve_external_guard(klass);
1882     if (k_mirror == nullptr) {
1883       return JVMTI_ERROR_INVALID_CLASS;
1884     }
1885     if (java_lang_Class::is_primitive(k_mirror)) {
1886       return JVMTI_ERROR_NONE;
1887     }
1888     k = java_lang_Class::as_Klass(k_mirror);
1889     if (klass == nullptr) {
1890       return JVMTI_ERROR_INVALID_CLASS;
1891     }
1892   }
1893 
1894   if (initial_object != nullptr) {
1895     oop init_obj = JNIHandles::resolve_external_guard(initial_object);
1896     if (init_obj == nullptr) {
1897       return JVMTI_ERROR_INVALID_OBJECT;
1898     }
1899   }
1900 
1901   Thread *thread = Thread::current();
1902   HandleMark hm(thread);
1903 
1904   TraceTime t("FollowReferences", TRACETIME_LOG(Debug, jvmti, objecttagging));
1905   JvmtiTagMap::tag_map_for(this)->follow_references(heap_filter, k, initial_object, callbacks, user_data);
1906   return JVMTI_ERROR_NONE;
1907 } /* end FollowReferences */
1908 
1909 
1910 // klass - null is a valid value, must be checked
1911 // callbacks - pre-checked for null
1912 // user_data - null is a valid value, must be checked
1913 jvmtiError
1914 JvmtiEnv::IterateThroughHeap(jint heap_filter, jclass klass, const jvmtiHeapCallbacks* callbacks, const void* user_data) {
1915   // check klass if provided
1916   Klass* k = nullptr;
1917   if (klass != nullptr) {
1918     oop k_mirror = JNIHandles::resolve_external_guard(klass);
1919     if (k_mirror == nullptr) {
1920       return JVMTI_ERROR_INVALID_CLASS;
1921     }
1922     if (java_lang_Class::is_primitive(k_mirror)) {
1923       return JVMTI_ERROR_NONE;
1924     }
1925     k = java_lang_Class::as_Klass(k_mirror);
1926     if (k == nullptr) {
1927       return JVMTI_ERROR_INVALID_CLASS;
1928     }
1929   }
1930 
1931   TraceTime t("IterateThroughHeap", TRACETIME_LOG(Debug, jvmti, objecttagging));
1932   JvmtiTagMap::tag_map_for(this)->iterate_through_heap(heap_filter, k, callbacks, user_data);
1933   return JVMTI_ERROR_NONE;
1934 } /* end IterateThroughHeap */
1935 
1936 
1937 // tag_ptr - pre-checked for null
1938 jvmtiError
1939 JvmtiEnv::GetTag(jobject object, jlong* tag_ptr) {
1940   oop o = JNIHandles::resolve_external_guard(object);
1941   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
1942   *tag_ptr = JvmtiTagMap::tag_map_for(this)->get_tag(object);
1943   return JVMTI_ERROR_NONE;
1944 } /* end GetTag */
1945 
1946 
1947 jvmtiError
1948 JvmtiEnv::SetTag(jobject object, jlong tag) {
1949   oop o = JNIHandles::resolve_external_guard(object);
1950   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
1951   JvmtiTagMap::tag_map_for(this)->set_tag(object, tag);
1952   return JVMTI_ERROR_NONE;
1953 } /* end SetTag */
1954 
1955 
1956 // tag_count - pre-checked to be greater than or equal to 0
1957 // tags - pre-checked for null
1958 // count_ptr - pre-checked for null
1959 // object_result_ptr - null is a valid value, must be checked
1960 // tag_result_ptr - null is a valid value, must be checked
1961 jvmtiError
1962 JvmtiEnv::GetObjectsWithTags(jint tag_count, const jlong* tags, jint* count_ptr, jobject** object_result_ptr, jlong** tag_result_ptr) {
1963   TraceTime t("GetObjectsWithTags", TRACETIME_LOG(Debug, jvmti, objecttagging));
1964   return JvmtiTagMap::tag_map_for(this)->get_objects_with_tags((jlong*)tags, tag_count, count_ptr, object_result_ptr, tag_result_ptr);
1965 } /* end GetObjectsWithTags */
1966 
1967 
1968 jvmtiError
1969 JvmtiEnv::ForceGarbageCollection() {
1970   Universe::heap()->collect(GCCause::_jvmti_force_gc);
1971   return JVMTI_ERROR_NONE;
1972 } /* end ForceGarbageCollection */
1973 
1974 
1975   //
1976   // Heap (1.0) functions
1977   //
1978 
1979 // object_reference_callback - pre-checked for null
1980 // user_data - null is a valid value, must be checked
1981 jvmtiError
1982 JvmtiEnv::IterateOverObjectsReachableFromObject(jobject object, jvmtiObjectReferenceCallback object_reference_callback, const void* user_data) {
1983   oop o = JNIHandles::resolve_external_guard(object);
1984   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
1985   JvmtiTagMap::tag_map_for(this)->iterate_over_objects_reachable_from_object(object, object_reference_callback, user_data);
1986   return JVMTI_ERROR_NONE;
1987 } /* end IterateOverObjectsReachableFromObject */
1988 
1989 
1990 // heap_root_callback - null is a valid value, must be checked
1991 // stack_ref_callback - null is a valid value, must be checked
1992 // object_ref_callback - null is a valid value, must be checked
1993 // user_data - null is a valid value, must be checked
1994 jvmtiError
1995 JvmtiEnv::IterateOverReachableObjects(jvmtiHeapRootCallback heap_root_callback, jvmtiStackReferenceCallback stack_ref_callback, jvmtiObjectReferenceCallback object_ref_callback, const void* user_data) {
1996   TraceTime t("IterateOverReachableObjects", TRACETIME_LOG(Debug, jvmti, objecttagging));
1997   JvmtiTagMap::tag_map_for(this)->iterate_over_reachable_objects(heap_root_callback, stack_ref_callback, object_ref_callback, user_data);
1998   return JVMTI_ERROR_NONE;
1999 } /* end IterateOverReachableObjects */
2000 
2001 
2002 // heap_object_callback - pre-checked for null
2003 // user_data - null is a valid value, must be checked
2004 jvmtiError
2005 JvmtiEnv::IterateOverHeap(jvmtiHeapObjectFilter object_filter, jvmtiHeapObjectCallback heap_object_callback, const void* user_data) {
2006   TraceTime t("IterateOverHeap", TRACETIME_LOG(Debug, jvmti, objecttagging));
2007   Thread *thread = Thread::current();
2008   HandleMark hm(thread);
2009   JvmtiTagMap::tag_map_for(this)->iterate_over_heap(object_filter, nullptr, heap_object_callback, user_data);
2010   return JVMTI_ERROR_NONE;
2011 } /* end IterateOverHeap */
2012 
2013 
2014 // k_mirror - may be primitive, this must be checked
2015 // heap_object_callback - pre-checked for null
2016 // user_data - null is a valid value, must be checked
2017 jvmtiError
2018 JvmtiEnv::IterateOverInstancesOfClass(oop k_mirror, jvmtiHeapObjectFilter object_filter, jvmtiHeapObjectCallback heap_object_callback, const void* user_data) {
2019   if (java_lang_Class::is_primitive(k_mirror)) {
2020     // DO PRIMITIVE CLASS PROCESSING
2021     return JVMTI_ERROR_NONE;
2022   }
2023   Klass* klass = java_lang_Class::as_Klass(k_mirror);
2024   if (klass == nullptr) {
2025     return JVMTI_ERROR_INVALID_CLASS;
2026   }
2027   TraceTime t("IterateOverInstancesOfClass", TRACETIME_LOG(Debug, jvmti, objecttagging));
2028   JvmtiTagMap::tag_map_for(this)->iterate_over_heap(object_filter, klass, heap_object_callback, user_data);
2029   return JVMTI_ERROR_NONE;
2030 } /* end IterateOverInstancesOfClass */
2031 
2032 
2033   //
2034   // Local Variable functions
2035   //
2036 
2037 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2038 // depth - pre-checked as non-negative
2039 // value_ptr - pre-checked for null
2040 jvmtiError
2041 JvmtiEnv::GetLocalObject(jthread thread, jint depth, jint slot, jobject* value_ptr) {
2042   JavaThread* current_thread = JavaThread::current();
2043   // rm object is created to clean up the javaVFrame created in
2044   // doit_prologue(), but after doit() is finished with it.
2045   ResourceMark rm(current_thread);
2046   HandleMark hm(current_thread);
2047   JvmtiVTMSTransitionDisabler disabler(thread);
2048   ThreadsListHandle tlh(current_thread);
2049 
2050   JavaThread* java_thread = nullptr;
2051   oop thread_obj = nullptr;
2052   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2053   if (err != JVMTI_ERROR_NONE) {
2054     return err;
2055   }
2056   bool self = is_JavaThread_current(java_thread, thread_obj);
2057 
2058   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2059     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2060                                      current_thread, depth, slot, self);
2061     VMThread::execute(&op);
2062     err = op.result();
2063     if (err == JVMTI_ERROR_NONE) {
2064       *value_ptr = op.value().l;
2065     }
2066   } else {
2067     // Support for ordinary threads
2068     VM_GetOrSetLocal op(java_thread, current_thread, depth, slot, self);
2069     VMThread::execute(&op);
2070     err = op.result();
2071     if (err == JVMTI_ERROR_NONE) {
2072       *value_ptr = op.value().l;
2073     }
2074   }
2075   return err;
2076 } /* end GetLocalObject */
2077 
2078 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2079 // depth - pre-checked as non-negative
2080 // value - pre-checked for null
2081 jvmtiError
2082 JvmtiEnv::GetLocalInstance(jthread thread, jint depth, jobject* value_ptr){
2083   JavaThread* current_thread = JavaThread::current();
2084   // rm object is created to clean up the javaVFrame created in
2085   // doit_prologue(), but after doit() is finished with it.
2086   ResourceMark rm(current_thread);
2087   HandleMark hm(current_thread);
2088   JvmtiVTMSTransitionDisabler disabler(thread);
2089   ThreadsListHandle tlh(current_thread);
2090 
2091   JavaThread* java_thread = nullptr;
2092   oop thread_obj = nullptr;
2093   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2094   if (err != JVMTI_ERROR_NONE) {
2095     return err;
2096   }
2097   bool self = is_JavaThread_current(java_thread, thread_obj);
2098 
2099   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2100     VM_VirtualThreadGetReceiver op(this, Handle(current_thread, thread_obj),
2101                                    current_thread, depth, self);
2102     VMThread::execute(&op);
2103     err = op.result();
2104     if (err == JVMTI_ERROR_NONE) {
2105       *value_ptr = op.value().l;
2106     }
2107   } else {
2108     // Support for ordinary threads
2109     VM_GetReceiver op(java_thread, current_thread, depth, self);
2110     VMThread::execute(&op);
2111     err = op.result();
2112     if (err == JVMTI_ERROR_NONE) {
2113       *value_ptr = op.value().l;
2114     }
2115   }
2116   return err;
2117 } /* end GetLocalInstance */
2118 
2119 
2120 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2121 // depth - pre-checked as non-negative
2122 // value_ptr - pre-checked for null
2123 jvmtiError
2124 JvmtiEnv::GetLocalInt(jthread thread, jint depth, jint slot, jint* value_ptr) {
2125   JavaThread* current_thread = JavaThread::current();
2126   // rm object is created to clean up the javaVFrame created in
2127   // doit_prologue(), but after doit() is finished with it.
2128   ResourceMark rm(current_thread);
2129   HandleMark hm(current_thread);
2130   JvmtiVTMSTransitionDisabler disabler(thread);
2131   ThreadsListHandle tlh(current_thread);
2132 
2133   JavaThread* java_thread = nullptr;
2134   oop thread_obj = nullptr;
2135   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2136   if (err != JVMTI_ERROR_NONE) {
2137     return err;
2138   }
2139   bool self = is_JavaThread_current(java_thread, thread_obj);
2140 
2141   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2142     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2143                                      depth, slot, T_INT, self);
2144     VMThread::execute(&op);
2145     err = op.result();
2146     if (err == JVMTI_ERROR_NONE) {
2147       *value_ptr = op.value().i;
2148     }
2149   } else {
2150     // Support for ordinary threads
2151     VM_GetOrSetLocal op(java_thread, depth, slot, T_INT, self);
2152     VMThread::execute(&op);
2153     err = op.result();
2154     if (err == JVMTI_ERROR_NONE) {
2155       *value_ptr = op.value().i;
2156     }
2157   }
2158   return err;
2159 } /* end GetLocalInt */
2160 
2161 
2162 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2163 // depth - pre-checked as non-negative
2164 // value_ptr - pre-checked for null
2165 jvmtiError
2166 JvmtiEnv::GetLocalLong(jthread thread, jint depth, jint slot, jlong* value_ptr) {
2167   JavaThread* current_thread = JavaThread::current();
2168   // rm object is created to clean up the javaVFrame created in
2169   // doit_prologue(), but after doit() is finished with it.
2170   ResourceMark rm(current_thread);
2171   HandleMark hm(current_thread);
2172   JvmtiVTMSTransitionDisabler disabler(thread);
2173   ThreadsListHandle tlh(current_thread);
2174 
2175   JavaThread* java_thread = nullptr;
2176   oop thread_obj = nullptr;
2177   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2178   if (err != JVMTI_ERROR_NONE) {
2179     return err;
2180   }
2181   bool self = is_JavaThread_current(java_thread, thread_obj);
2182 
2183   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2184     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2185                                      depth, slot, T_LONG, self);
2186     VMThread::execute(&op);
2187     err = op.result();
2188     if (err == JVMTI_ERROR_NONE) {
2189       *value_ptr = op.value().j;
2190     }
2191   } else {
2192     // Support for ordinary threads
2193     VM_GetOrSetLocal op(java_thread, depth, slot, T_LONG, self);
2194     VMThread::execute(&op);
2195     err = op.result();
2196     if (err == JVMTI_ERROR_NONE) {
2197       *value_ptr = op.value().j;
2198     }
2199   }
2200   return err;
2201 } /* end GetLocalLong */
2202 
2203 
2204 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2205 // depth - pre-checked as non-negative
2206 // value_ptr - pre-checked for null
2207 jvmtiError
2208 JvmtiEnv::GetLocalFloat(jthread thread, jint depth, jint slot, jfloat* value_ptr) {
2209   JavaThread* current_thread = JavaThread::current();
2210   // rm object is created to clean up the javaVFrame created in
2211   // doit_prologue(), but after doit() is finished with it.
2212   ResourceMark rm(current_thread);
2213   HandleMark hm(current_thread);
2214   JvmtiVTMSTransitionDisabler disabler(thread);
2215   ThreadsListHandle tlh(current_thread);
2216 
2217   JavaThread* java_thread = nullptr;
2218   oop thread_obj = nullptr;
2219   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2220   if (err != JVMTI_ERROR_NONE) {
2221     return err;
2222   }
2223   bool self = is_JavaThread_current(java_thread, thread_obj);
2224 
2225   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2226     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2227                                      depth, slot, T_FLOAT, self);
2228     VMThread::execute(&op);
2229     err = op.result();
2230     if (err == JVMTI_ERROR_NONE) {
2231       *value_ptr = op.value().f;
2232     }
2233   } else {
2234     // Support for ordinary threads
2235     VM_GetOrSetLocal op(java_thread, depth, slot, T_FLOAT, self);
2236     VMThread::execute(&op);
2237     err = op.result();
2238     if (err == JVMTI_ERROR_NONE) {
2239       *value_ptr = op.value().f;
2240     }
2241   }
2242   return err;
2243 } /* end GetLocalFloat */
2244 
2245 
2246 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2247 // depth - pre-checked as non-negative
2248 // value_ptr - pre-checked for null
2249 jvmtiError
2250 JvmtiEnv::GetLocalDouble(jthread thread, jint depth, jint slot, jdouble* value_ptr) {
2251   JavaThread* current_thread = JavaThread::current();
2252   // rm object is created to clean up the javaVFrame created in
2253   // doit_prologue(), but after doit() is finished with it.
2254   ResourceMark rm(current_thread);
2255   HandleMark hm(current_thread);
2256   JvmtiVTMSTransitionDisabler disabler(thread);
2257   ThreadsListHandle tlh(current_thread);
2258 
2259   JavaThread* java_thread = nullptr;
2260   oop thread_obj = nullptr;
2261   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2262   if (err != JVMTI_ERROR_NONE) {
2263     return err;
2264   }
2265   bool self = is_JavaThread_current(java_thread, thread_obj);
2266 
2267   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2268     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2269                                      depth, slot, T_DOUBLE, self);
2270     VMThread::execute(&op);
2271     err = op.result();
2272     if (err == JVMTI_ERROR_NONE) {
2273       *value_ptr = op.value().d;
2274     }
2275   } else {
2276     // Support for ordinary threads
2277     VM_GetOrSetLocal op(java_thread, depth, slot, T_DOUBLE, self);
2278     VMThread::execute(&op);
2279     err = op.result();
2280     if (err == JVMTI_ERROR_NONE) {
2281       *value_ptr = op.value().d;
2282     }
2283   }
2284   return err;
2285 } /* end GetLocalDouble */
2286 
2287 
2288 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2289 // depth - pre-checked as non-negative
2290 jvmtiError
2291 JvmtiEnv::SetLocalObject(jthread thread, jint depth, jint slot, jobject value) {
2292   JavaThread* current_thread = JavaThread::current();
2293   // rm object is created to clean up the javaVFrame created in
2294   // doit_prologue(), but after doit() is finished with it.
2295   ResourceMark rm(current_thread);
2296   HandleMark hm(current_thread);
2297   JvmtiVTMSTransitionDisabler disabler(thread);
2298   ThreadsListHandle tlh(current_thread);
2299 
2300   JavaThread* java_thread = nullptr;
2301   oop thread_obj = nullptr;
2302   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2303   if (err != JVMTI_ERROR_NONE) {
2304     return err;
2305   }
2306   bool self = is_JavaThread_current(java_thread, thread_obj);
2307   jvalue val;
2308   val.l = value;
2309 
2310   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2311     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2312                                      depth, slot, T_OBJECT, val, self);
2313     VMThread::execute(&op);
2314     err = op.result();
2315   } else {
2316     // Support for ordinary threads
2317     VM_GetOrSetLocal op(java_thread, depth, slot, T_OBJECT, val, self);
2318     VMThread::execute(&op);
2319     err = op.result();
2320   }
2321   return err;
2322 } /* end SetLocalObject */
2323 
2324 
2325 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2326 // depth - pre-checked as non-negative
2327 jvmtiError
2328 JvmtiEnv::SetLocalInt(jthread thread, jint depth, jint slot, jint value) {
2329   JavaThread* current_thread = JavaThread::current();
2330   // rm object is created to clean up the javaVFrame created in
2331   // doit_prologue(), but after doit() is finished with it.
2332   ResourceMark rm(current_thread);
2333   HandleMark hm(current_thread);
2334   JvmtiVTMSTransitionDisabler disabler(thread);
2335   ThreadsListHandle tlh(current_thread);
2336 
2337   JavaThread* java_thread = nullptr;
2338   oop thread_obj = nullptr;
2339   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2340   if (err != JVMTI_ERROR_NONE) {
2341     return err;
2342   }
2343   bool self = is_JavaThread_current(java_thread, thread_obj);
2344   jvalue val;
2345   val.i = value;
2346 
2347   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2348     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2349                                      depth, slot, T_INT, val, self);
2350     VMThread::execute(&op);
2351     err = op.result();
2352   } else {
2353     // Support for ordinary threads
2354     VM_GetOrSetLocal op(java_thread, depth, slot, T_INT, val, self);
2355     VMThread::execute(&op);
2356     err = op.result();
2357   }
2358   return err;
2359 } /* end SetLocalInt */
2360 
2361 
2362 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2363 // depth - pre-checked as non-negative
2364 jvmtiError
2365 JvmtiEnv::SetLocalLong(jthread thread, jint depth, jint slot, jlong value) {
2366   JavaThread* current_thread = JavaThread::current();
2367   // rm object is created to clean up the javaVFrame created in
2368   // doit_prologue(), but after doit() is finished with it.
2369   ResourceMark rm(current_thread);
2370   HandleMark hm(current_thread);
2371   JvmtiVTMSTransitionDisabler disabler(thread);
2372   ThreadsListHandle tlh(current_thread);
2373 
2374   JavaThread* java_thread = nullptr;
2375   oop thread_obj = nullptr;
2376   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2377   if (err != JVMTI_ERROR_NONE) {
2378     return err;
2379   }
2380   bool self = is_JavaThread_current(java_thread, thread_obj);
2381   jvalue val;
2382   val.j = value;
2383 
2384   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2385     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2386                                      depth, slot, T_LONG, val, self);
2387     VMThread::execute(&op);
2388     err = op.result();
2389   } else {
2390     // Support for ordinary threads
2391     VM_GetOrSetLocal op(java_thread, depth, slot, T_LONG, val, self);
2392     VMThread::execute(&op);
2393     err = op.result();
2394   }
2395   return err;
2396 } /* end SetLocalLong */
2397 
2398 
2399 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2400 // depth - pre-checked as non-negative
2401 jvmtiError
2402 JvmtiEnv::SetLocalFloat(jthread thread, jint depth, jint slot, jfloat value) {
2403   JavaThread* current_thread = JavaThread::current();
2404   // rm object is created to clean up the javaVFrame created in
2405   // doit_prologue(), but after doit() is finished with it.
2406   ResourceMark rm(current_thread);
2407   HandleMark hm(current_thread);
2408   JvmtiVTMSTransitionDisabler disabler(thread);
2409   ThreadsListHandle tlh(current_thread);
2410 
2411   JavaThread* java_thread = nullptr;
2412   oop thread_obj = nullptr;
2413   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2414   if (err != JVMTI_ERROR_NONE) {
2415     return err;
2416   }
2417   bool self = is_JavaThread_current(java_thread, thread_obj);
2418   jvalue val;
2419   val.f = value;
2420 
2421   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2422     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2423                                      depth, slot, T_FLOAT, val, self);
2424     VMThread::execute(&op);
2425     err = op.result();
2426   } else {
2427     // Support for ordinary threads
2428     VM_GetOrSetLocal op(java_thread, depth, slot, T_FLOAT, val, self);
2429     VMThread::execute(&op);
2430     err = op.result();
2431   }
2432   return err;
2433 } /* end SetLocalFloat */
2434 
2435 
2436 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2437 // depth - pre-checked as non-negative
2438 jvmtiError
2439 JvmtiEnv::SetLocalDouble(jthread thread, jint depth, jint slot, jdouble value) {
2440   JavaThread* current_thread = JavaThread::current();
2441   // rm object is created to clean up the javaVFrame created in
2442   // doit_prologue(), but after doit() is finished with it.
2443   ResourceMark rm(current_thread);
2444   HandleMark hm(current_thread);
2445   JvmtiVTMSTransitionDisabler disabler(thread);
2446   ThreadsListHandle tlh(current_thread);
2447 
2448   JavaThread* java_thread = nullptr;
2449   oop thread_obj = nullptr;
2450   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2451   if (err != JVMTI_ERROR_NONE) {
2452     return err;
2453   }
2454   bool self = is_JavaThread_current(java_thread, thread_obj);
2455   jvalue val;
2456   val.d = value;
2457 
2458   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2459     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2460                                      depth, slot, T_DOUBLE, val, self);
2461     VMThread::execute(&op);
2462     err = op.result();
2463   } else {
2464     // Support for ordinary threads
2465     VM_GetOrSetLocal op(java_thread, depth, slot, T_DOUBLE, val, self);
2466     VMThread::execute(&op);
2467     err = op.result();
2468   }
2469   return err;
2470 } /* end SetLocalDouble */
2471 
2472 
2473   //
2474   // Breakpoint functions
2475   //
2476 
2477 // method - pre-checked for validity, but may be null meaning obsolete method
2478 jvmtiError
2479 JvmtiEnv::SetBreakpoint(Method* method, jlocation location) {
2480   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
2481   if (location < 0) {   // simple invalid location check first
2482     return JVMTI_ERROR_INVALID_LOCATION;
2483   }
2484   // verify that the breakpoint is not past the end of the method
2485   if (location >= (jlocation) method->code_size()) {
2486     return JVMTI_ERROR_INVALID_LOCATION;
2487   }
2488 
2489   ResourceMark rm;
2490   JvmtiBreakpoint bp(method, location);
2491   JvmtiBreakpoints& jvmti_breakpoints = JvmtiCurrentBreakpoints::get_jvmti_breakpoints();
2492   if (jvmti_breakpoints.set(bp) == JVMTI_ERROR_DUPLICATE)
2493     return JVMTI_ERROR_DUPLICATE;
2494 
2495   if (TraceJVMTICalls) {
2496     jvmti_breakpoints.print();
2497   }
2498 
2499   return JVMTI_ERROR_NONE;
2500 } /* end SetBreakpoint */
2501 
2502 
2503 // method - pre-checked for validity, but may be null meaning obsolete method
2504 jvmtiError
2505 JvmtiEnv::ClearBreakpoint(Method* method, jlocation location) {
2506   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
2507 
2508   if (location < 0) {   // simple invalid location check first
2509     return JVMTI_ERROR_INVALID_LOCATION;
2510   }
2511 
2512   // verify that the breakpoint is not past the end of the method
2513   if (location >= (jlocation) method->code_size()) {
2514     return JVMTI_ERROR_INVALID_LOCATION;
2515   }
2516 
2517   JvmtiBreakpoint bp(method, location);
2518 
2519   JvmtiBreakpoints& jvmti_breakpoints = JvmtiCurrentBreakpoints::get_jvmti_breakpoints();
2520   if (jvmti_breakpoints.clear(bp) == JVMTI_ERROR_NOT_FOUND)
2521     return JVMTI_ERROR_NOT_FOUND;
2522 
2523   if (TraceJVMTICalls) {
2524     jvmti_breakpoints.print();
2525   }
2526 
2527   return JVMTI_ERROR_NONE;
2528 } /* end ClearBreakpoint */
2529 
2530 
2531   //
2532   // Watched Field functions
2533   //
2534 
2535 jvmtiError
2536 JvmtiEnv::SetFieldAccessWatch(fieldDescriptor* fdesc_ptr) {
2537   // make sure we haven't set this watch before
2538   if (fdesc_ptr->is_field_access_watched()) return JVMTI_ERROR_DUPLICATE;
2539   fdesc_ptr->set_is_field_access_watched(true);
2540 
2541   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_ACCESS, true);
2542 
2543   return JVMTI_ERROR_NONE;
2544 } /* end SetFieldAccessWatch */
2545 
2546 
2547 jvmtiError
2548 JvmtiEnv::ClearFieldAccessWatch(fieldDescriptor* fdesc_ptr) {
2549   // make sure we have a watch to clear
2550   if (!fdesc_ptr->is_field_access_watched()) return JVMTI_ERROR_NOT_FOUND;
2551   fdesc_ptr->set_is_field_access_watched(false);
2552 
2553   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_ACCESS, false);
2554 
2555   return JVMTI_ERROR_NONE;
2556 } /* end ClearFieldAccessWatch */
2557 
2558 
2559 jvmtiError
2560 JvmtiEnv::SetFieldModificationWatch(fieldDescriptor* fdesc_ptr) {
2561   // make sure we haven't set this watch before
2562   if (fdesc_ptr->is_field_modification_watched()) return JVMTI_ERROR_DUPLICATE;
2563   fdesc_ptr->set_is_field_modification_watched(true);
2564 
2565   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_MODIFICATION, true);
2566 
2567   return JVMTI_ERROR_NONE;
2568 } /* end SetFieldModificationWatch */
2569 
2570 
2571 jvmtiError
2572 JvmtiEnv::ClearFieldModificationWatch(fieldDescriptor* fdesc_ptr) {
2573    // make sure we have a watch to clear
2574   if (!fdesc_ptr->is_field_modification_watched()) return JVMTI_ERROR_NOT_FOUND;
2575   fdesc_ptr->set_is_field_modification_watched(false);
2576 
2577   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_MODIFICATION, false);
2578 
2579   return JVMTI_ERROR_NONE;
2580 } /* end ClearFieldModificationWatch */
2581 
2582   //
2583   // Class functions
2584   //
2585 
2586 
2587 // k_mirror - may be primitive, this must be checked
2588 // signature_ptr - null is a valid value, must be checked
2589 // generic_ptr - null is a valid value, must be checked
2590 jvmtiError
2591 JvmtiEnv::GetClassSignature(oop k_mirror, char** signature_ptr, char** generic_ptr) {
2592   ResourceMark rm;
2593   bool isPrimitive = java_lang_Class::is_primitive(k_mirror);
2594   Klass* k = nullptr;
2595   if (!isPrimitive) {
2596     k = java_lang_Class::as_Klass(k_mirror);
2597     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2598   }
2599   if (signature_ptr != nullptr) {
2600     char* result = nullptr;
2601     if (isPrimitive) {
2602       char tchar = type2char(java_lang_Class::primitive_type(k_mirror));
2603       result = (char*) jvmtiMalloc(2);
2604       result[0] = tchar;
2605       result[1] = '\0';
2606     } else {
2607       const char* class_sig = k->signature_name();
2608       result = (char *) jvmtiMalloc(strlen(class_sig)+1);
2609       strcpy(result, class_sig);
2610     }
2611     *signature_ptr = result;
2612   }
2613   if (generic_ptr != nullptr) {
2614     *generic_ptr = nullptr;
2615     if (!isPrimitive && k->is_instance_klass()) {
2616       Symbol* soo = InstanceKlass::cast(k)->generic_signature();
2617       if (soo != nullptr) {
2618         const char *gen_sig = soo->as_C_string();
2619         if (gen_sig != nullptr) {
2620           char* gen_result;
2621           jvmtiError err = allocate(strlen(gen_sig) + 1,
2622                                     (unsigned char **)&gen_result);
2623           if (err != JVMTI_ERROR_NONE) {
2624             return err;
2625           }
2626           strcpy(gen_result, gen_sig);
2627           *generic_ptr = gen_result;
2628         }
2629       }
2630     }
2631   }
2632   return JVMTI_ERROR_NONE;
2633 } /* end GetClassSignature */
2634 
2635 
2636 // k_mirror - may be primitive, this must be checked
2637 // status_ptr - pre-checked for null
2638 jvmtiError
2639 JvmtiEnv::GetClassStatus(oop k_mirror, jint* status_ptr) {
2640   jint result = 0;
2641   if (java_lang_Class::is_primitive(k_mirror)) {
2642     result |= JVMTI_CLASS_STATUS_PRIMITIVE;
2643   } else {
2644     Klass* k = java_lang_Class::as_Klass(k_mirror);
2645     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2646     result = k->jvmti_class_status();
2647   }
2648   *status_ptr = result;
2649 
2650   return JVMTI_ERROR_NONE;
2651 } /* end GetClassStatus */
2652 
2653 
2654 // k_mirror - may be primitive, this must be checked
2655 // source_name_ptr - pre-checked for null
2656 jvmtiError
2657 JvmtiEnv::GetSourceFileName(oop k_mirror, char** source_name_ptr) {
2658   if (java_lang_Class::is_primitive(k_mirror)) {
2659      return JVMTI_ERROR_ABSENT_INFORMATION;
2660   }
2661   Klass* k_klass = java_lang_Class::as_Klass(k_mirror);
2662   NULL_CHECK(k_klass, JVMTI_ERROR_INVALID_CLASS);
2663 
2664   if (!k_klass->is_instance_klass()) {
2665     return JVMTI_ERROR_ABSENT_INFORMATION;
2666   }
2667 
2668   Symbol* sfnOop = InstanceKlass::cast(k_klass)->source_file_name();
2669   NULL_CHECK(sfnOop, JVMTI_ERROR_ABSENT_INFORMATION);
2670   {
2671     JavaThread* current_thread  = JavaThread::current();
2672     ResourceMark rm(current_thread);
2673     const char* sfncp = (const char*) sfnOop->as_C_string();
2674     *source_name_ptr = (char *) jvmtiMalloc(strlen(sfncp)+1);
2675     strcpy(*source_name_ptr, sfncp);
2676   }
2677 
2678   return JVMTI_ERROR_NONE;
2679 } /* end GetSourceFileName */
2680 
2681 
2682 // k_mirror - may be primitive, this must be checked
2683 // modifiers_ptr - pre-checked for null
2684 jvmtiError
2685 JvmtiEnv::GetClassModifiers(oop k_mirror, jint* modifiers_ptr) {
2686   JavaThread* current_thread  = JavaThread::current();
2687   jint result = 0;
2688   if (!java_lang_Class::is_primitive(k_mirror)) {
2689     Klass* k = java_lang_Class::as_Klass(k_mirror);
2690     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2691     result = k->compute_modifier_flags();
2692 
2693     // Reset the deleted  ACC_SUPER bit (deleted in compute_modifier_flags()).
2694     // if (k->is_super()) {
2695     //   result |= JVM_ACC_SUPER;
2696     // }
2697   } else {
2698     result = (JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC);
2699   }
2700   *modifiers_ptr = result;
2701 
2702   return JVMTI_ERROR_NONE;
2703 } /* end GetClassModifiers */
2704 
2705 
2706 // k_mirror - may be primitive, this must be checked
2707 // method_count_ptr - pre-checked for null
2708 // methods_ptr - pre-checked for null
2709 jvmtiError
2710 JvmtiEnv::GetClassMethods(oop k_mirror, jint* method_count_ptr, jmethodID** methods_ptr) {
2711   JavaThread* current_thread  = JavaThread::current();
2712   HandleMark hm(current_thread);
2713 
2714   if (java_lang_Class::is_primitive(k_mirror)) {
2715     *method_count_ptr = 0;
2716     *methods_ptr = (jmethodID*) jvmtiMalloc(0 * sizeof(jmethodID));
2717     return JVMTI_ERROR_NONE;
2718   }
2719   Klass* k = java_lang_Class::as_Klass(k_mirror);
2720   NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2721 
2722   // Return CLASS_NOT_PREPARED error as per JVMTI spec.
2723   if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) )) {
2724     return JVMTI_ERROR_CLASS_NOT_PREPARED;
2725   }
2726 
2727   if (!k->is_instance_klass()) {
2728     *method_count_ptr = 0;
2729     *methods_ptr = (jmethodID*) jvmtiMalloc(0 * sizeof(jmethodID));
2730     return JVMTI_ERROR_NONE;
2731   }
2732   InstanceKlass* ik = InstanceKlass::cast(k);
2733   // Allocate the result and fill it in
2734   int result_length = ik->methods()->length();
2735   jmethodID* result_list = (jmethodID*)jvmtiMalloc(result_length * sizeof(jmethodID));
2736   int index;
2737   bool jmethodids_found = true;
2738   int skipped = 0;  // skip overpass methods
2739 
2740   for (index = 0; index < result_length; index++) {
2741     Method* m = ik->methods()->at(index);
2742     // Depending on can_maintain_original_method_order capability use the original
2743     // method ordering indices stored in the class, so we can emit jmethodIDs in
2744     // the order they appeared in the class file or just copy in current order.
2745     int result_index = JvmtiExport::can_maintain_original_method_order() ? ik->method_ordering()->at(index) : index;
2746     assert(result_index >= 0 && result_index < result_length, "invalid original method index");
2747     if (m->is_overpass()) {
2748       result_list[result_index] = nullptr;
2749       skipped++;
2750       continue;
2751     }
2752     jmethodID id;
2753     if (jmethodids_found) {
2754       id = m->find_jmethod_id_or_null();
2755       if (id == nullptr) {
2756         // If we find an uninitialized value, make sure there is
2757         // enough space for all the uninitialized values we might
2758         // find.
2759         ik->ensure_space_for_methodids(index);
2760         jmethodids_found = false;
2761         id = m->jmethod_id();
2762       }
2763     } else {
2764       id = m->jmethod_id();
2765     }
2766     result_list[result_index] = id;
2767   }
2768 
2769   // Fill in return value.
2770   if (skipped > 0) {
2771     // copy results skipping null methodIDs
2772     *methods_ptr = (jmethodID*)jvmtiMalloc((result_length - skipped) * sizeof(jmethodID));
2773     *method_count_ptr = result_length - skipped;
2774     for (index = 0, skipped = 0; index < result_length; index++) {
2775       if (result_list[index] == nullptr) {
2776         skipped++;
2777       } else {
2778         (*methods_ptr)[index - skipped] = result_list[index];
2779       }
2780     }
2781     deallocate((unsigned char *)result_list);
2782   } else {
2783     *method_count_ptr = result_length;
2784     *methods_ptr = result_list;
2785   }
2786 
2787   return JVMTI_ERROR_NONE;
2788 } /* end GetClassMethods */
2789 
2790 
2791 // k_mirror - may be primitive, this must be checked
2792 // field_count_ptr - pre-checked for null
2793 // fields_ptr - pre-checked for null
2794 jvmtiError
2795 JvmtiEnv::GetClassFields(oop k_mirror, jint* field_count_ptr, jfieldID** fields_ptr) {
2796   if (java_lang_Class::is_primitive(k_mirror)) {
2797     *field_count_ptr = 0;
2798     *fields_ptr = (jfieldID*) jvmtiMalloc(0 * sizeof(jfieldID));
2799     return JVMTI_ERROR_NONE;
2800   }
2801   JavaThread* current_thread = JavaThread::current();
2802   HandleMark hm(current_thread);
2803   Klass* k = java_lang_Class::as_Klass(k_mirror);
2804   NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2805 
2806   // Return CLASS_NOT_PREPARED error as per JVMTI spec.
2807   if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) )) {
2808     return JVMTI_ERROR_CLASS_NOT_PREPARED;
2809   }
2810 
2811   if (!k->is_instance_klass()) {
2812     *field_count_ptr = 0;
2813     *fields_ptr = (jfieldID*) jvmtiMalloc(0 * sizeof(jfieldID));
2814     return JVMTI_ERROR_NONE;
2815   }
2816 
2817   InstanceKlass* ik = InstanceKlass::cast(k);
2818 
2819   FilteredJavaFieldStream flds(ik);
2820 
2821   int result_count = flds.field_count();
2822 
2823   // Allocate the result and fill it in.
2824   jfieldID* result_list = (jfieldID*)jvmtiMalloc(result_count * sizeof(jfieldID));
2825   for (int i = 0; i < result_count; i++, flds.next()) {
2826     result_list[i] = jfieldIDWorkaround::to_jfieldID(ik, flds.offset(),
2827                                                      flds.access_flags().is_static(),
2828                                                      flds.field_descriptor().is_flat());
2829   }
2830   assert(flds.done(), "just checking");
2831 
2832   // Fill in the results
2833   *field_count_ptr = result_count;
2834   *fields_ptr = result_list;
2835 
2836   return JVMTI_ERROR_NONE;
2837 } /* end GetClassFields */
2838 
2839 
2840 // k_mirror - may be primitive, this must be checked
2841 // interface_count_ptr - pre-checked for null
2842 // interfaces_ptr - pre-checked for null
2843 jvmtiError
2844 JvmtiEnv::GetImplementedInterfaces(oop k_mirror, jint* interface_count_ptr, jclass** interfaces_ptr) {
2845   {
2846     if (java_lang_Class::is_primitive(k_mirror)) {
2847       *interface_count_ptr = 0;
2848       *interfaces_ptr = (jclass*) jvmtiMalloc(0 * sizeof(jclass));
2849       return JVMTI_ERROR_NONE;
2850     }
2851     JavaThread* current_thread = JavaThread::current();
2852     HandleMark hm(current_thread);
2853     Klass* k = java_lang_Class::as_Klass(k_mirror);
2854     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2855 
2856     // Return CLASS_NOT_PREPARED error as per JVMTI spec.
2857     if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) ))
2858       return JVMTI_ERROR_CLASS_NOT_PREPARED;
2859 
2860     if (!k->is_instance_klass()) {
2861       *interface_count_ptr = 0;
2862       *interfaces_ptr = (jclass*) jvmtiMalloc(0 * sizeof(jclass));
2863       return JVMTI_ERROR_NONE;
2864     }
2865 
2866     InstanceKlass* ik = InstanceKlass::cast(k);
2867     Array<InstanceKlass*>* interface_list = ik->local_interfaces();
2868     int result_length = (interface_list == nullptr ? 0 : interface_list->length());
2869     jclass* result_list = (jclass*) jvmtiMalloc(result_length * sizeof(jclass));
2870     for (int i_index = 0; i_index < result_length; i_index += 1) {
2871       InstanceKlass* klass_at = interface_list->at(i_index);
2872       assert(klass_at->is_klass(), "interfaces must be Klass*s");
2873       assert(klass_at->is_interface(), "interfaces must be interfaces");
2874       oop mirror_at = klass_at->java_mirror();
2875       Handle handle_at = Handle(current_thread, mirror_at);
2876       result_list[i_index] = (jclass) jni_reference(handle_at);
2877     }
2878     *interface_count_ptr = result_length;
2879     *interfaces_ptr = result_list;
2880   }
2881 
2882   return JVMTI_ERROR_NONE;
2883 } /* end GetImplementedInterfaces */
2884 
2885 
2886 // k_mirror - may be primitive, this must be checked
2887 // minor_version_ptr - pre-checked for null
2888 // major_version_ptr - pre-checked for null
2889 jvmtiError
2890 JvmtiEnv::GetClassVersionNumbers(oop k_mirror, jint* minor_version_ptr, jint* major_version_ptr) {
2891   if (java_lang_Class::is_primitive(k_mirror)) {
2892     return JVMTI_ERROR_ABSENT_INFORMATION;
2893   }
2894   Klass* klass = java_lang_Class::as_Klass(k_mirror);
2895 
2896   jint status = klass->jvmti_class_status();
2897   if (status & (JVMTI_CLASS_STATUS_ERROR)) {
2898     return JVMTI_ERROR_INVALID_CLASS;
2899   }
2900   if (status & (JVMTI_CLASS_STATUS_ARRAY)) {
2901     return JVMTI_ERROR_ABSENT_INFORMATION;
2902   }
2903 
2904   InstanceKlass* ik = InstanceKlass::cast(klass);
2905   *minor_version_ptr = ik->minor_version();
2906   *major_version_ptr = ik->major_version();
2907 
2908   return JVMTI_ERROR_NONE;
2909 } /* end GetClassVersionNumbers */
2910 
2911 
2912 // k_mirror - may be primitive, this must be checked
2913 // constant_pool_count_ptr - pre-checked for null
2914 // constant_pool_byte_count_ptr - pre-checked for null
2915 // constant_pool_bytes_ptr - pre-checked for null
2916 jvmtiError
2917 JvmtiEnv::GetConstantPool(oop k_mirror, jint* constant_pool_count_ptr, jint* constant_pool_byte_count_ptr, unsigned char** constant_pool_bytes_ptr) {
2918   if (java_lang_Class::is_primitive(k_mirror)) {
2919     return JVMTI_ERROR_ABSENT_INFORMATION;
2920   }
2921 
2922   Klass* klass = java_lang_Class::as_Klass(k_mirror);
2923   Thread *thread = Thread::current();
2924   ResourceMark rm(thread);
2925 
2926   jint status = klass->jvmti_class_status();
2927   if (status & (JVMTI_CLASS_STATUS_ERROR)) {
2928     return JVMTI_ERROR_INVALID_CLASS;
2929   }
2930   if (status & (JVMTI_CLASS_STATUS_ARRAY)) {
2931     return JVMTI_ERROR_ABSENT_INFORMATION;
2932   }
2933 
2934   InstanceKlass* ik = InstanceKlass::cast(klass);
2935   JvmtiConstantPoolReconstituter reconstituter(ik);
2936   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
2937     return reconstituter.get_error();
2938   }
2939 
2940   unsigned char *cpool_bytes;
2941   int cpool_size = reconstituter.cpool_size();
2942   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
2943     return reconstituter.get_error();
2944   }
2945   jvmtiError res = allocate(cpool_size, &cpool_bytes);
2946   if (res != JVMTI_ERROR_NONE) {
2947     return res;
2948   }
2949   reconstituter.copy_cpool_bytes(cpool_bytes);
2950   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
2951     return reconstituter.get_error();
2952   }
2953 
2954   constantPoolHandle  constants(thread, ik->constants());
2955   *constant_pool_count_ptr      = constants->length();
2956   *constant_pool_byte_count_ptr = cpool_size;
2957   *constant_pool_bytes_ptr      = cpool_bytes;
2958 
2959   return JVMTI_ERROR_NONE;
2960 } /* end GetConstantPool */
2961 
2962 
2963 // k_mirror - may be primitive, this must be checked
2964 // is_interface_ptr - pre-checked for null
2965 jvmtiError
2966 JvmtiEnv::IsInterface(oop k_mirror, jboolean* is_interface_ptr) {
2967   {
2968     bool result = false;
2969     if (!java_lang_Class::is_primitive(k_mirror)) {
2970       Klass* k = java_lang_Class::as_Klass(k_mirror);
2971       if (k != nullptr && k->is_interface()) {
2972         result = true;
2973       }
2974     }
2975     *is_interface_ptr = result;
2976   }
2977 
2978   return JVMTI_ERROR_NONE;
2979 } /* end IsInterface */
2980 
2981 
2982 // k_mirror - may be primitive, this must be checked
2983 // is_array_class_ptr - pre-checked for null
2984 jvmtiError
2985 JvmtiEnv::IsArrayClass(oop k_mirror, jboolean* is_array_class_ptr) {
2986   {
2987     bool result = false;
2988     if (!java_lang_Class::is_primitive(k_mirror)) {
2989       Klass* k = java_lang_Class::as_Klass(k_mirror);
2990       if (k != nullptr && k->is_array_klass()) {
2991         result = true;
2992       }
2993     }
2994     *is_array_class_ptr = result;
2995   }
2996 
2997   return JVMTI_ERROR_NONE;
2998 } /* end IsArrayClass */
2999 
3000 
3001 // k_mirror - may be primitive, this must be checked
3002 // classloader_ptr - pre-checked for null
3003 jvmtiError
3004 JvmtiEnv::GetClassLoader(oop k_mirror, jobject* classloader_ptr) {
3005   {
3006     if (java_lang_Class::is_primitive(k_mirror)) {
3007       *classloader_ptr = (jclass) jni_reference(Handle());
3008       return JVMTI_ERROR_NONE;
3009     }
3010     JavaThread* current_thread = JavaThread::current();
3011     HandleMark hm(current_thread);
3012     Klass* k = java_lang_Class::as_Klass(k_mirror);
3013     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3014 
3015     oop result_oop = k->class_loader();
3016     if (result_oop == nullptr) {
3017       *classloader_ptr = (jclass) jni_reference(Handle());
3018       return JVMTI_ERROR_NONE;
3019     }
3020     Handle result_handle = Handle(current_thread, result_oop);
3021     jclass result_jnihandle = (jclass) jni_reference(result_handle);
3022     *classloader_ptr = result_jnihandle;
3023   }
3024   return JVMTI_ERROR_NONE;
3025 } /* end GetClassLoader */
3026 
3027 
3028 // k_mirror - may be primitive, this must be checked
3029 // source_debug_extension_ptr - pre-checked for null
3030 jvmtiError
3031 JvmtiEnv::GetSourceDebugExtension(oop k_mirror, char** source_debug_extension_ptr) {
3032   {
3033     if (java_lang_Class::is_primitive(k_mirror)) {
3034       return JVMTI_ERROR_ABSENT_INFORMATION;
3035     }
3036     Klass* k = java_lang_Class::as_Klass(k_mirror);
3037     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3038     if (!k->is_instance_klass()) {
3039       return JVMTI_ERROR_ABSENT_INFORMATION;
3040     }
3041     const char* sde = InstanceKlass::cast(k)->source_debug_extension();
3042     NULL_CHECK(sde, JVMTI_ERROR_ABSENT_INFORMATION);
3043 
3044     {
3045       *source_debug_extension_ptr = (char *) jvmtiMalloc(strlen(sde)+1);
3046       strcpy(*source_debug_extension_ptr, sde);
3047     }
3048   }
3049 
3050   return JVMTI_ERROR_NONE;
3051 } /* end GetSourceDebugExtension */
3052 
3053   //
3054   // Object functions
3055   //
3056 
3057 // hash_code_ptr - pre-checked for null
3058 jvmtiError
3059 JvmtiEnv::GetObjectHashCode(jobject object, jint* hash_code_ptr) {
3060   oop mirror = JNIHandles::resolve_external_guard(object);
3061   NULL_CHECK(mirror, JVMTI_ERROR_INVALID_OBJECT);
3062   NULL_CHECK(hash_code_ptr, JVMTI_ERROR_NULL_POINTER);
3063 
3064   {
3065     jint result = (jint) mirror->identity_hash();
3066     *hash_code_ptr = result;
3067   }
3068   return JVMTI_ERROR_NONE;
3069 } /* end GetObjectHashCode */
3070 
3071 
3072 // info_ptr - pre-checked for null
3073 jvmtiError
3074 JvmtiEnv::GetObjectMonitorUsage(jobject object, jvmtiMonitorUsage* info_ptr) {
3075   // This needs to be performed at a safepoint to gather stable data
3076   // because monitor owner / waiters might not be suspended.
3077   VM_GetObjectMonitorUsage op(this, JavaThread::current(), object, info_ptr);
3078   VMThread::execute(&op);
3079   return op.result();
3080 } /* end GetObjectMonitorUsage */
3081 
3082 
3083   //
3084   // Field functions
3085   //
3086 
3087 // name_ptr - null is a valid value, must be checked
3088 // signature_ptr - null is a valid value, must be checked
3089 // generic_ptr - null is a valid value, must be checked
3090 jvmtiError
3091 JvmtiEnv::GetFieldName(fieldDescriptor* fdesc_ptr, char** name_ptr, char** signature_ptr, char** generic_ptr) {
3092   JavaThread* current_thread  = JavaThread::current();
3093   ResourceMark rm(current_thread);
3094   if (name_ptr == nullptr) {
3095     // just don't return the name
3096   } else {
3097     const char* fieldName = fdesc_ptr->name()->as_C_string();
3098     *name_ptr =  (char*) jvmtiMalloc(strlen(fieldName) + 1);
3099     if (*name_ptr == nullptr)
3100       return JVMTI_ERROR_OUT_OF_MEMORY;
3101     strcpy(*name_ptr, fieldName);
3102   }
3103   if (signature_ptr== nullptr) {
3104     // just don't return the signature
3105   } else {
3106     const char* fieldSignature = fdesc_ptr->signature()->as_C_string();
3107     *signature_ptr = (char*) jvmtiMalloc(strlen(fieldSignature) + 1);
3108     if (*signature_ptr == nullptr)
3109       return JVMTI_ERROR_OUT_OF_MEMORY;
3110     strcpy(*signature_ptr, fieldSignature);
3111   }
3112   if (generic_ptr != nullptr) {
3113     *generic_ptr = nullptr;
3114     Symbol* soop = fdesc_ptr->generic_signature();
3115     if (soop != nullptr) {
3116       const char* gen_sig = soop->as_C_string();
3117       if (gen_sig != nullptr) {
3118         jvmtiError err = allocate(strlen(gen_sig) + 1, (unsigned char **)generic_ptr);
3119         if (err != JVMTI_ERROR_NONE) {
3120           return err;
3121         }
3122         strcpy(*generic_ptr, gen_sig);
3123       }
3124     }
3125   }
3126   return JVMTI_ERROR_NONE;
3127 } /* end GetFieldName */
3128 
3129 
3130 // declaring_class_ptr - pre-checked for null
3131 jvmtiError
3132 JvmtiEnv::GetFieldDeclaringClass(fieldDescriptor* fdesc_ptr, jclass* declaring_class_ptr) {
3133 
3134   *declaring_class_ptr = get_jni_class_non_null(fdesc_ptr->field_holder());
3135   return JVMTI_ERROR_NONE;
3136 } /* end GetFieldDeclaringClass */
3137 
3138 
3139 // modifiers_ptr - pre-checked for null
3140 jvmtiError
3141 JvmtiEnv::GetFieldModifiers(fieldDescriptor* fdesc_ptr, jint* modifiers_ptr) {
3142 
3143   AccessFlags resultFlags = fdesc_ptr->access_flags();
3144   jint result = resultFlags.as_int();
3145   *modifiers_ptr = result;
3146 
3147   return JVMTI_ERROR_NONE;
3148 } /* end GetFieldModifiers */
3149 
3150 
3151 // is_synthetic_ptr - pre-checked for null
3152 jvmtiError
3153 JvmtiEnv::IsFieldSynthetic(fieldDescriptor* fdesc_ptr, jboolean* is_synthetic_ptr) {
3154   *is_synthetic_ptr = fdesc_ptr->is_synthetic();
3155   return JVMTI_ERROR_NONE;
3156 } /* end IsFieldSynthetic */
3157 
3158 
3159   //
3160   // Method functions
3161   //
3162 
3163 // method - pre-checked for validity, but may be null meaning obsolete method
3164 // name_ptr - null is a valid value, must be checked
3165 // signature_ptr - null is a valid value, must be checked
3166 // generic_ptr - null is a valid value, must be checked
3167 jvmtiError
3168 JvmtiEnv::GetMethodName(Method* method, char** name_ptr, char** signature_ptr, char** generic_ptr) {
3169   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3170   JavaThread* current_thread  = JavaThread::current();
3171 
3172   ResourceMark rm(current_thread); // get the utf8 name and signature
3173   if (name_ptr == nullptr) {
3174     // just don't return the name
3175   } else {
3176     const char* utf8_name = (const char *) method->name()->as_utf8();
3177     *name_ptr = (char *) jvmtiMalloc(strlen(utf8_name)+1);
3178     strcpy(*name_ptr, utf8_name);
3179   }
3180   if (signature_ptr == nullptr) {
3181     // just don't return the signature
3182   } else {
3183     const char* utf8_signature = (const char *) method->signature()->as_utf8();
3184     *signature_ptr = (char *) jvmtiMalloc(strlen(utf8_signature) + 1);
3185     strcpy(*signature_ptr, utf8_signature);
3186   }
3187 
3188   if (generic_ptr != nullptr) {
3189     *generic_ptr = nullptr;
3190     Symbol* soop = method->generic_signature();
3191     if (soop != nullptr) {
3192       const char* gen_sig = soop->as_C_string();
3193       if (gen_sig != nullptr) {
3194         jvmtiError err = allocate(strlen(gen_sig) + 1, (unsigned char **)generic_ptr);
3195         if (err != JVMTI_ERROR_NONE) {
3196           return err;
3197         }
3198         strcpy(*generic_ptr, gen_sig);
3199       }
3200     }
3201   }
3202   return JVMTI_ERROR_NONE;
3203 } /* end GetMethodName */
3204 
3205 
3206 // method - pre-checked for validity, but may be null meaning obsolete method
3207 // declaring_class_ptr - pre-checked for null
3208 jvmtiError
3209 JvmtiEnv::GetMethodDeclaringClass(Method* method, jclass* declaring_class_ptr) {
3210   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3211   (*declaring_class_ptr) = get_jni_class_non_null(method->method_holder());
3212   return JVMTI_ERROR_NONE;
3213 } /* end GetMethodDeclaringClass */
3214 
3215 
3216 // method - pre-checked for validity, but may be null meaning obsolete method
3217 // modifiers_ptr - pre-checked for null
3218 jvmtiError
3219 JvmtiEnv::GetMethodModifiers(Method* method, jint* modifiers_ptr) {
3220   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3221   (*modifiers_ptr) = method->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS;
3222   return JVMTI_ERROR_NONE;
3223 } /* end GetMethodModifiers */
3224 
3225 
3226 // method - pre-checked for validity, but may be null meaning obsolete method
3227 // max_ptr - pre-checked for null
3228 jvmtiError
3229 JvmtiEnv::GetMaxLocals(Method* method, jint* max_ptr) {
3230   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3231   // get max stack
3232   (*max_ptr) = method->max_locals();
3233   return JVMTI_ERROR_NONE;
3234 } /* end GetMaxLocals */
3235 
3236 
3237 // method - pre-checked for validity, but may be null meaning obsolete method
3238 // size_ptr - pre-checked for null
3239 jvmtiError
3240 JvmtiEnv::GetArgumentsSize(Method* method, jint* size_ptr) {
3241   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3242   // get size of arguments
3243 
3244   (*size_ptr) = method->size_of_parameters();
3245   return JVMTI_ERROR_NONE;
3246 } /* end GetArgumentsSize */
3247 
3248 
3249 // method - pre-checked for validity, but may be null meaning obsolete method
3250 // entry_count_ptr - pre-checked for null
3251 // table_ptr - pre-checked for null
3252 jvmtiError
3253 JvmtiEnv::GetLineNumberTable(Method* method, jint* entry_count_ptr, jvmtiLineNumberEntry** table_ptr) {
3254   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3255   if (!method->has_linenumber_table()) {
3256     return (JVMTI_ERROR_ABSENT_INFORMATION);
3257   }
3258 
3259   // The line number table is compressed so we don't know how big it is until decompressed.
3260   // Decompression is really fast so we just do it twice.
3261 
3262   // Compute size of table
3263   jint num_entries = 0;
3264   CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
3265   while (stream.read_pair()) {
3266     num_entries++;
3267   }
3268   jvmtiLineNumberEntry *jvmti_table =
3269             (jvmtiLineNumberEntry *)jvmtiMalloc(num_entries * (sizeof(jvmtiLineNumberEntry)));
3270 
3271   // Fill jvmti table
3272   if (num_entries > 0) {
3273     int index = 0;
3274     CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
3275     while (stream.read_pair()) {
3276       jvmti_table[index].start_location = (jlocation) stream.bci();
3277       jvmti_table[index].line_number = (jint) stream.line();
3278       index++;
3279     }
3280     assert(index == num_entries, "sanity check");
3281   }
3282 
3283   // Set up results
3284   (*entry_count_ptr) = num_entries;
3285   (*table_ptr) = jvmti_table;
3286 
3287   return JVMTI_ERROR_NONE;
3288 } /* end GetLineNumberTable */
3289 
3290 
3291 // method - pre-checked for validity, but may be null meaning obsolete method
3292 // start_location_ptr - pre-checked for null
3293 // end_location_ptr - pre-checked for null
3294 jvmtiError
3295 JvmtiEnv::GetMethodLocation(Method* method, jlocation* start_location_ptr, jlocation* end_location_ptr) {
3296 
3297   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3298   // get start and end location
3299   (*end_location_ptr) = (jlocation) (method->code_size() - 1);
3300   if (method->code_size() == 0) {
3301     // there is no code so there is no start location
3302     (*start_location_ptr) = (jlocation)(-1);
3303   } else {
3304     (*start_location_ptr) = (jlocation)(0);
3305   }
3306 
3307   return JVMTI_ERROR_NONE;
3308 } /* end GetMethodLocation */
3309 
3310 
3311 // method - pre-checked for validity, but may be null meaning obsolete method
3312 // entry_count_ptr - pre-checked for null
3313 // table_ptr - pre-checked for null
3314 jvmtiError
3315 JvmtiEnv::GetLocalVariableTable(Method* method, jint* entry_count_ptr, jvmtiLocalVariableEntry** table_ptr) {
3316 
3317   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3318   JavaThread* current_thread  = JavaThread::current();
3319 
3320   // does the klass have any local variable information?
3321   InstanceKlass* ik = method->method_holder();
3322   if (!ik->has_localvariable_table()) {
3323     return (JVMTI_ERROR_ABSENT_INFORMATION);
3324   }
3325 
3326   ConstantPool* constants = method->constants();
3327   NULL_CHECK(constants, JVMTI_ERROR_ABSENT_INFORMATION);
3328 
3329   // in the vm localvariable table representation, 6 consecutive elements in the table
3330   // represent a 6-tuple of shorts
3331   // [start_pc, length, name_index, descriptor_index, signature_index, index]
3332   jint num_entries = method->localvariable_table_length();
3333   jvmtiLocalVariableEntry *jvmti_table = (jvmtiLocalVariableEntry *)
3334                 jvmtiMalloc(num_entries * (sizeof(jvmtiLocalVariableEntry)));
3335 
3336   if (num_entries > 0) {
3337     LocalVariableTableElement* table = method->localvariable_table_start();
3338     for (int i = 0; i < num_entries; i++) {
3339       // get the 5 tuple information from the vm table
3340       jlocation start_location = (jlocation) table[i].start_bci;
3341       jint length = (jint) table[i].length;
3342       int name_index = (int) table[i].name_cp_index;
3343       int signature_index = (int) table[i].descriptor_cp_index;
3344       int generic_signature_index = (int) table[i].signature_cp_index;
3345       jint slot = (jint) table[i].slot;
3346 
3347       // get utf8 name and signature
3348       char *name_buf = nullptr;
3349       char *sig_buf = nullptr;
3350       char *gen_sig_buf = nullptr;
3351       {
3352         ResourceMark rm(current_thread);
3353 
3354         const char *utf8_name = (const char *) constants->symbol_at(name_index)->as_utf8();
3355         name_buf = (char *) jvmtiMalloc(strlen(utf8_name)+1);
3356         strcpy(name_buf, utf8_name);
3357 
3358         const char *utf8_signature = (const char *) constants->symbol_at(signature_index)->as_utf8();
3359         sig_buf = (char *) jvmtiMalloc(strlen(utf8_signature)+1);
3360         strcpy(sig_buf, utf8_signature);
3361 
3362         if (generic_signature_index > 0) {
3363           const char *utf8_gen_sign = (const char *)
3364                                        constants->symbol_at(generic_signature_index)->as_utf8();
3365           gen_sig_buf = (char *) jvmtiMalloc(strlen(utf8_gen_sign)+1);
3366           strcpy(gen_sig_buf, utf8_gen_sign);
3367         }
3368       }
3369 
3370       // fill in the jvmti local variable table
3371       jvmti_table[i].start_location = start_location;
3372       jvmti_table[i].length = length;
3373       jvmti_table[i].name = name_buf;
3374       jvmti_table[i].signature = sig_buf;
3375       jvmti_table[i].generic_signature = gen_sig_buf;
3376       jvmti_table[i].slot = slot;
3377     }
3378   }
3379 
3380   // set results
3381   (*entry_count_ptr) = num_entries;
3382   (*table_ptr) = jvmti_table;
3383 
3384   return JVMTI_ERROR_NONE;
3385 } /* end GetLocalVariableTable */
3386 
3387 
3388 // method - pre-checked for validity, but may be null meaning obsolete method
3389 // bytecode_count_ptr - pre-checked for null
3390 // bytecodes_ptr - pre-checked for null
3391 jvmtiError
3392 JvmtiEnv::GetBytecodes(Method* method, jint* bytecode_count_ptr, unsigned char** bytecodes_ptr) {
3393   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3394 
3395   methodHandle mh(Thread::current(), method);
3396   jint size = (jint)mh->code_size();
3397   jvmtiError err = allocate(size, bytecodes_ptr);
3398   if (err != JVMTI_ERROR_NONE) {
3399     return err;
3400   }
3401 
3402   (*bytecode_count_ptr) = size;
3403   // get byte codes
3404   JvmtiClassFileReconstituter::copy_bytecodes(mh, *bytecodes_ptr);
3405 
3406   return JVMTI_ERROR_NONE;
3407 } /* end GetBytecodes */
3408 
3409 
3410 // method - pre-checked for validity, but may be null meaning obsolete method
3411 // is_native_ptr - pre-checked for null
3412 jvmtiError
3413 JvmtiEnv::IsMethodNative(Method* method, jboolean* is_native_ptr) {
3414   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3415   (*is_native_ptr) = method->is_native();
3416   return JVMTI_ERROR_NONE;
3417 } /* end IsMethodNative */
3418 
3419 
3420 // method - pre-checked for validity, but may be null meaning obsolete method
3421 // is_synthetic_ptr - pre-checked for null
3422 jvmtiError
3423 JvmtiEnv::IsMethodSynthetic(Method* method, jboolean* is_synthetic_ptr) {
3424   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3425   (*is_synthetic_ptr) = method->is_synthetic();
3426   return JVMTI_ERROR_NONE;
3427 } /* end IsMethodSynthetic */
3428 
3429 
3430 // method - pre-checked for validity, but may be null meaning obsolete method
3431 // is_obsolete_ptr - pre-checked for null
3432 jvmtiError
3433 JvmtiEnv::IsMethodObsolete(Method* method, jboolean* is_obsolete_ptr) {
3434   if (use_version_1_0_semantics() &&
3435       get_capabilities()->can_redefine_classes == 0) {
3436     // This JvmtiEnv requested version 1.0 semantics and this function
3437     // requires the can_redefine_classes capability in version 1.0 so
3438     // we need to return an error here.
3439     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
3440   }
3441 
3442   if (method == nullptr || method->is_obsolete()) {
3443     *is_obsolete_ptr = true;
3444   } else {
3445     *is_obsolete_ptr = false;
3446   }
3447   return JVMTI_ERROR_NONE;
3448 } /* end IsMethodObsolete */
3449 
3450   //
3451   // Raw Monitor functions
3452   //
3453 
3454 // name - pre-checked for null
3455 // monitor_ptr - pre-checked for null
3456 jvmtiError
3457 JvmtiEnv::CreateRawMonitor(const char* name, jrawMonitorID* monitor_ptr) {
3458   JvmtiRawMonitor* rmonitor = new (std::nothrow) JvmtiRawMonitor(name);
3459   NULL_CHECK(rmonitor, JVMTI_ERROR_OUT_OF_MEMORY);
3460 
3461   *monitor_ptr = (jrawMonitorID)rmonitor;
3462 
3463   return JVMTI_ERROR_NONE;
3464 } /* end CreateRawMonitor */
3465 
3466 
3467 // rmonitor - pre-checked for validity
3468 jvmtiError
3469 JvmtiEnv::DestroyRawMonitor(JvmtiRawMonitor * rmonitor) {
3470   if (Threads::number_of_threads() == 0) {
3471     // Remove this monitor from pending raw monitors list
3472     // if it has entered in onload or start phase.
3473     JvmtiPendingMonitors::destroy(rmonitor);
3474   } else {
3475     Thread* thread  = Thread::current();
3476     if (rmonitor->owner() == thread) {
3477       // The caller owns this monitor which we are about to destroy.
3478       // We exit the underlying synchronization object so that the
3479       // "delete monitor" call below can work without an assertion
3480       // failure on systems that don't like destroying synchronization
3481       // objects that are locked.
3482       int r;
3483       int recursion = rmonitor->recursions();
3484       for (int i = 0; i <= recursion; i++) {
3485         r = rmonitor->raw_exit(thread);
3486         assert(r == JvmtiRawMonitor::M_OK, "raw_exit should have worked");
3487         if (r != JvmtiRawMonitor::M_OK) {  // robustness
3488           return JVMTI_ERROR_INTERNAL;
3489         }
3490       }
3491     }
3492     if (rmonitor->owner() != nullptr) {
3493       // The caller is trying to destroy a monitor that is locked by
3494       // someone else. While this is not forbidden by the JVMTI
3495       // spec, it will cause an assertion failure on systems that don't
3496       // like destroying synchronization objects that are locked.
3497       // We indicate a problem with the error return (and leak the
3498       // monitor's memory).
3499       return JVMTI_ERROR_NOT_MONITOR_OWNER;
3500     }
3501   }
3502 
3503   delete rmonitor;
3504 
3505   return JVMTI_ERROR_NONE;
3506 } /* end DestroyRawMonitor */
3507 
3508 
3509 // rmonitor - pre-checked for validity
3510 jvmtiError
3511 JvmtiEnv::RawMonitorEnter(JvmtiRawMonitor * rmonitor) {
3512   if (Threads::number_of_threads() == 0) {
3513     // No JavaThreads exist so JvmtiRawMonitor enter cannot be
3514     // used, add this raw monitor to the pending list.
3515     // The pending monitors will be actually entered when
3516     // the VM is setup.
3517     // See transition_pending_raw_monitors in create_vm()
3518     // in thread.cpp.
3519     JvmtiPendingMonitors::enter(rmonitor);
3520   } else {
3521     Thread* thread = Thread::current();
3522     // 8266889: raw_enter changes Java thread state, needs WXWrite
3523     MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
3524     rmonitor->raw_enter(thread);
3525   }
3526   return JVMTI_ERROR_NONE;
3527 } /* end RawMonitorEnter */
3528 
3529 
3530 // rmonitor - pre-checked for validity
3531 jvmtiError
3532 JvmtiEnv::RawMonitorExit(JvmtiRawMonitor * rmonitor) {
3533   jvmtiError err = JVMTI_ERROR_NONE;
3534 
3535   if (Threads::number_of_threads() == 0) {
3536     // No JavaThreads exist so just remove this monitor from the pending list.
3537     // Bool value from exit is false if rmonitor is not in the list.
3538     if (!JvmtiPendingMonitors::exit(rmonitor)) {
3539       err = JVMTI_ERROR_NOT_MONITOR_OWNER;
3540     }
3541   } else {
3542     Thread* thread = Thread::current();
3543     int r = rmonitor->raw_exit(thread);
3544     if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3545       err = JVMTI_ERROR_NOT_MONITOR_OWNER;
3546     }
3547   }
3548   return err;
3549 } /* end RawMonitorExit */
3550 
3551 
3552 // rmonitor - pre-checked for validity
3553 jvmtiError
3554 JvmtiEnv::RawMonitorWait(JvmtiRawMonitor * rmonitor, jlong millis) {
3555   Thread* thread = Thread::current();
3556   // 8266889: raw_wait changes Java thread state, needs WXWrite
3557   MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
3558   int r = rmonitor->raw_wait(millis, thread);
3559 
3560   switch (r) {
3561   case JvmtiRawMonitor::M_INTERRUPTED:
3562     return JVMTI_ERROR_INTERRUPT;
3563   case JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE:
3564     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3565   default:
3566     return JVMTI_ERROR_NONE;
3567   }
3568 } /* end RawMonitorWait */
3569 
3570 
3571 // rmonitor - pre-checked for validity
3572 jvmtiError
3573 JvmtiEnv::RawMonitorNotify(JvmtiRawMonitor * rmonitor) {
3574   Thread* thread = Thread::current();
3575   int r = rmonitor->raw_notify(thread);
3576 
3577   if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3578     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3579   }
3580   return JVMTI_ERROR_NONE;
3581 } /* end RawMonitorNotify */
3582 
3583 
3584 // rmonitor - pre-checked for validity
3585 jvmtiError
3586 JvmtiEnv::RawMonitorNotifyAll(JvmtiRawMonitor * rmonitor) {
3587   Thread* thread = Thread::current();
3588   int r = rmonitor->raw_notifyAll(thread);
3589 
3590   if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3591     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3592   }
3593   return JVMTI_ERROR_NONE;
3594 } /* end RawMonitorNotifyAll */
3595 
3596 
3597   //
3598   // JNI Function Interception functions
3599   //
3600 
3601 
3602 // function_table - pre-checked for null
3603 jvmtiError
3604 JvmtiEnv::SetJNIFunctionTable(const jniNativeInterface* function_table) {
3605   // Copy jni function table at safepoint.
3606   VM_JNIFunctionTableCopier copier(function_table);
3607   VMThread::execute(&copier);
3608 
3609   return JVMTI_ERROR_NONE;
3610 } /* end SetJNIFunctionTable */
3611 
3612 
3613 // function_table - pre-checked for null
3614 jvmtiError
3615 JvmtiEnv::GetJNIFunctionTable(jniNativeInterface** function_table) {
3616   *function_table=(jniNativeInterface*)jvmtiMalloc(sizeof(jniNativeInterface));
3617   if (*function_table == nullptr)
3618     return JVMTI_ERROR_OUT_OF_MEMORY;
3619   memcpy(*function_table,(JavaThread::current())->get_jni_functions(),sizeof(jniNativeInterface));
3620   return JVMTI_ERROR_NONE;
3621 } /* end GetJNIFunctionTable */
3622 
3623 
3624   //
3625   // Event Management functions
3626   //
3627 
3628 jvmtiError
3629 JvmtiEnv::GenerateEvents(jvmtiEvent event_type) {
3630   // can only generate two event types
3631   if (event_type != JVMTI_EVENT_COMPILED_METHOD_LOAD &&
3632       event_type != JVMTI_EVENT_DYNAMIC_CODE_GENERATED) {
3633     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
3634   }
3635 
3636   // for compiled_method_load events we must check that the environment
3637   // has the can_generate_compiled_method_load_events capability.
3638   if (event_type == JVMTI_EVENT_COMPILED_METHOD_LOAD) {
3639     if (get_capabilities()->can_generate_compiled_method_load_events == 0) {
3640       return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
3641     }
3642     return JvmtiCodeBlobEvents::generate_compiled_method_load_events(this);
3643   } else {
3644     return JvmtiCodeBlobEvents::generate_dynamic_code_events(this);
3645   }
3646 
3647 } /* end GenerateEvents */
3648 
3649 
3650   //
3651   // Extension Mechanism functions
3652   //
3653 
3654 // extension_count_ptr - pre-checked for null
3655 // extensions - pre-checked for null
3656 jvmtiError
3657 JvmtiEnv::GetExtensionFunctions(jint* extension_count_ptr, jvmtiExtensionFunctionInfo** extensions) {
3658   return JvmtiExtensions::get_functions(this, extension_count_ptr, extensions);
3659 } /* end GetExtensionFunctions */
3660 
3661 
3662 // extension_count_ptr - pre-checked for null
3663 // extensions - pre-checked for null
3664 jvmtiError
3665 JvmtiEnv::GetExtensionEvents(jint* extension_count_ptr, jvmtiExtensionEventInfo** extensions) {
3666   return JvmtiExtensions::get_events(this, extension_count_ptr, extensions);
3667 } /* end GetExtensionEvents */
3668 
3669 
3670 // callback - null is a valid value, must be checked
3671 jvmtiError
3672 JvmtiEnv::SetExtensionEventCallback(jint extension_event_index, jvmtiExtensionEvent callback) {
3673   return JvmtiExtensions::set_event_callback(this, extension_event_index, callback);
3674 } /* end SetExtensionEventCallback */
3675 
3676   //
3677   // Timers functions
3678   //
3679 
3680 // info_ptr - pre-checked for null
3681 jvmtiError
3682 JvmtiEnv::GetCurrentThreadCpuTimerInfo(jvmtiTimerInfo* info_ptr) {
3683   os::current_thread_cpu_time_info(info_ptr);
3684   return JVMTI_ERROR_NONE;
3685 } /* end GetCurrentThreadCpuTimerInfo */
3686 
3687 
3688 // nanos_ptr - pre-checked for null
3689 jvmtiError
3690 JvmtiEnv::GetCurrentThreadCpuTime(jlong* nanos_ptr) {
3691   Thread* thread = Thread::current();
3692 
3693   // Surprisingly the GetCurrentThreadCpuTime is used by non-JavaThread's.
3694   if (thread->is_Java_thread()) {
3695     if (JavaThread::cast(thread)->is_vthread_mounted()) {
3696       // No support for a VirtualThread (yet).
3697       return JVMTI_ERROR_UNSUPPORTED_OPERATION;
3698     }
3699   }
3700   *nanos_ptr = os::current_thread_cpu_time();
3701   return JVMTI_ERROR_NONE;
3702 } /* end GetCurrentThreadCpuTime */
3703 
3704 
3705 // info_ptr - pre-checked for null
3706 jvmtiError
3707 JvmtiEnv::GetThreadCpuTimerInfo(jvmtiTimerInfo* info_ptr) {
3708   os::thread_cpu_time_info(info_ptr);
3709   return JVMTI_ERROR_NONE;
3710 } /* end GetThreadCpuTimerInfo */
3711 
3712 
3713 // nanos_ptr - pre-checked for null
3714 jvmtiError
3715 JvmtiEnv::GetThreadCpuTime(jthread thread, jlong* nanos_ptr) {
3716   JavaThread* current_thread = JavaThread::current();
3717   ThreadsListHandle tlh(current_thread);
3718   JavaThread* java_thread = nullptr;
3719   oop thread_oop = nullptr;
3720 
3721   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_oop);
3722 
3723   if (thread_oop != nullptr && thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
3724     // No support for virtual threads (yet).
3725     return JVMTI_ERROR_UNSUPPORTED_OPERATION;
3726   }
3727   if (err != JVMTI_ERROR_NONE) {
3728     return err;
3729   }
3730   NULL_CHECK(nanos_ptr, JVMTI_ERROR_NULL_POINTER);
3731 
3732   *nanos_ptr = os::thread_cpu_time(java_thread);
3733   return JVMTI_ERROR_NONE;
3734 } /* end GetThreadCpuTime */
3735 
3736 
3737 // info_ptr - pre-checked for null
3738 jvmtiError
3739 JvmtiEnv::GetTimerInfo(jvmtiTimerInfo* info_ptr) {
3740   os::javaTimeNanos_info(info_ptr);
3741   return JVMTI_ERROR_NONE;
3742 } /* end GetTimerInfo */
3743 
3744 
3745 // nanos_ptr - pre-checked for null
3746 jvmtiError
3747 JvmtiEnv::GetTime(jlong* nanos_ptr) {
3748   *nanos_ptr = os::javaTimeNanos();
3749   return JVMTI_ERROR_NONE;
3750 } /* end GetTime */
3751 
3752 
3753 // processor_count_ptr - pre-checked for null
3754 jvmtiError
3755 JvmtiEnv::GetAvailableProcessors(jint* processor_count_ptr) {
3756   *processor_count_ptr = os::active_processor_count();
3757   return JVMTI_ERROR_NONE;
3758 } /* end GetAvailableProcessors */
3759 
3760 jvmtiError
3761 JvmtiEnv::SetHeapSamplingInterval(jint sampling_interval) {
3762   if (sampling_interval < 0) {
3763     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
3764   }
3765   ThreadHeapSampler::set_sampling_interval(sampling_interval);
3766   return JVMTI_ERROR_NONE;
3767 } /* end SetHeapSamplingInterval */
3768 
3769   //
3770   // System Properties functions
3771   //
3772 
3773 // count_ptr - pre-checked for null
3774 // property_ptr - pre-checked for null
3775 jvmtiError
3776 JvmtiEnv::GetSystemProperties(jint* count_ptr, char*** property_ptr) {
3777   jvmtiError err = JVMTI_ERROR_NONE;
3778 
3779   // Get the number of readable properties.
3780   *count_ptr = Arguments::PropertyList_readable_count(Arguments::system_properties());
3781 
3782   // Allocate memory to hold the exact number of readable properties.
3783   err = allocate(*count_ptr * sizeof(char *), (unsigned char **)property_ptr);
3784   if (err != JVMTI_ERROR_NONE) {
3785     return err;
3786   }
3787   int readable_count = 0;
3788   // Loop through the system properties until all the readable properties are found.
3789   for (SystemProperty* p = Arguments::system_properties(); p != nullptr && readable_count < *count_ptr; p = p->next()) {
3790     if (p->readable()) {
3791       const char *key = p->key();
3792       char **tmp_value = *property_ptr+readable_count;
3793       readable_count++;
3794       err = allocate((strlen(key)+1) * sizeof(char), (unsigned char**)tmp_value);
3795       if (err == JVMTI_ERROR_NONE) {
3796         strcpy(*tmp_value, key);
3797       } else {
3798         // clean up previously allocated memory.
3799         for (int j = 0; j < readable_count; j++) {
3800           Deallocate((unsigned char*)*property_ptr+j);
3801         }
3802         Deallocate((unsigned char*)property_ptr);
3803         break;
3804       }
3805     }
3806   }
3807   assert(err != JVMTI_ERROR_NONE || readable_count == *count_ptr, "Bad readable property count");
3808   return err;
3809 } /* end GetSystemProperties */
3810 
3811 
3812 // property - pre-checked for null
3813 // value_ptr - pre-checked for null
3814 jvmtiError
3815 JvmtiEnv::GetSystemProperty(const char* property, char** value_ptr) {
3816   jvmtiError err = JVMTI_ERROR_NONE;
3817   const char *value;
3818 
3819   // Return JVMTI_ERROR_NOT_AVAILABLE if property is not readable or doesn't exist.
3820   value = Arguments::PropertyList_get_readable_value(Arguments::system_properties(), property);
3821   if (value == nullptr) {
3822     err =  JVMTI_ERROR_NOT_AVAILABLE;
3823   } else {
3824     err = allocate((strlen(value)+1) * sizeof(char), (unsigned char **)value_ptr);
3825     if (err == JVMTI_ERROR_NONE) {
3826       strcpy(*value_ptr, value);
3827     }
3828   }
3829   return err;
3830 } /* end GetSystemProperty */
3831 
3832 
3833 // property - pre-checked for null
3834 // value - null is a valid value, must be checked
3835 jvmtiError
3836 JvmtiEnv::SetSystemProperty(const char* property, const char* value_ptr) {
3837   for (SystemProperty* p = Arguments::system_properties(); p != nullptr; p = p->next()) {
3838     if (strcmp(property, p->key()) == 0) {
3839       if (p->writeable()) {
3840         if (p->set_value(value_ptr, AllocFailStrategy::RETURN_NULL)) {
3841           return JVMTI_ERROR_NONE;
3842         } else {
3843           return JVMTI_ERROR_OUT_OF_MEMORY;
3844         }
3845       } else {
3846         // We found a property, but it's not writeable
3847         return JVMTI_ERROR_NOT_AVAILABLE;
3848       }
3849     }
3850   }
3851 
3852   // We cannot find a property of the given name
3853   return JVMTI_ERROR_NOT_AVAILABLE;
3854 } /* end SetSystemProperty */