1 /*
   2  * Copyright (c) 2003, 2025, 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);
 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);
 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       size_t 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   JvmtiVTMSTransitionDisabler disabler(thread);
1354   ThreadsListHandle tlh(calling_thread);
1355 
1356   JavaThread* java_thread = nullptr;
1357   oop thread_oop = nullptr;
1358   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, calling_thread, &java_thread, &thread_oop);
1359   if (err != JVMTI_ERROR_NONE) {
1360     return err;
1361   }
1362 
1363   if (LockingMode == LM_LEGACY && java_thread == nullptr) {
1364     *owned_monitor_count_ptr = 0;
1365     return JVMTI_ERROR_NONE;
1366   }
1367 
1368   // growable array of jvmti monitors info on the C-heap
1369   GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list =
1370       new (mtServiceability) GrowableArray<jvmtiMonitorStackDepthInfo*>(1, mtServiceability);
1371 
1372   Handle thread_handle(calling_thread, thread_oop);
1373   EscapeBarrier eb(java_thread != nullptr, calling_thread, java_thread);
1374   if (!eb.deoptimize_objects(MaxJavaStackTraceDepth)) {
1375     delete owned_monitors_list;
1376     return JVMTI_ERROR_OUT_OF_MEMORY;
1377   }
1378   // get owned monitors info with handshake
1379   GetOwnedMonitorInfoClosure op(this, calling_thread, owned_monitors_list);
1380   JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1381   err = op.result();
1382 
1383   jint owned_monitor_count = owned_monitors_list->length();
1384   if (err == JVMTI_ERROR_NONE) {
1385     if ((err = allocate(owned_monitor_count * sizeof(jobject *),
1386                       (unsigned char**)owned_monitors_ptr)) == JVMTI_ERROR_NONE) {
1387       // copy into the returned array
1388       for (int i = 0; i < owned_monitor_count; i++) {
1389         (*owned_monitors_ptr)[i] =
1390           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->monitor;
1391       }
1392       *owned_monitor_count_ptr = owned_monitor_count;
1393     }
1394   }
1395   // clean up.
1396   for (int i = 0; i < owned_monitor_count; i++) {
1397     deallocate((unsigned char*)owned_monitors_list->at(i));
1398   }
1399   delete owned_monitors_list;
1400 
1401   return err;
1402 } /* end GetOwnedMonitorInfo */
1403 
1404 
1405 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1406 // monitor_info_count_ptr - pre-checked for null
1407 // monitor_info_ptr - pre-checked for null
1408 jvmtiError
1409 JvmtiEnv::GetOwnedMonitorStackDepthInfo(jthread thread, jint* monitor_info_count_ptr, jvmtiMonitorStackDepthInfo** monitor_info_ptr) {
1410   JavaThread* calling_thread = JavaThread::current();
1411   HandleMark hm(calling_thread);
1412 
1413   JvmtiVTMSTransitionDisabler disabler(thread);
1414   ThreadsListHandle tlh(calling_thread);
1415 
1416   JavaThread* java_thread = nullptr;
1417   oop thread_oop = nullptr;
1418   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, calling_thread, &java_thread, &thread_oop);
1419   if (err != JVMTI_ERROR_NONE) {
1420     return err;
1421   }
1422 
1423   if (LockingMode == LM_LEGACY && java_thread == nullptr) {
1424     *monitor_info_count_ptr = 0;
1425     return JVMTI_ERROR_NONE;
1426   }
1427 
1428   // growable array of jvmti monitors info on the C-heap
1429   GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list =
1430       new (mtServiceability) GrowableArray<jvmtiMonitorStackDepthInfo*>(1, mtServiceability);
1431 
1432   Handle thread_handle(calling_thread, thread_oop);
1433   EscapeBarrier eb(java_thread != nullptr, calling_thread, java_thread);
1434   if (!eb.deoptimize_objects(MaxJavaStackTraceDepth)) {
1435     delete owned_monitors_list;
1436     return JVMTI_ERROR_OUT_OF_MEMORY;
1437   }
1438   // get owned monitors info with handshake
1439   GetOwnedMonitorInfoClosure op(this, calling_thread, owned_monitors_list);
1440   JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1441   err = op.result();
1442 
1443   jint owned_monitor_count = owned_monitors_list->length();
1444   if (err == JVMTI_ERROR_NONE) {
1445     if ((err = allocate(owned_monitor_count * sizeof(jvmtiMonitorStackDepthInfo),
1446                         (unsigned char**)monitor_info_ptr)) == JVMTI_ERROR_NONE) {
1447       // copy to output array.
1448       for (int i = 0; i < owned_monitor_count; i++) {
1449         (*monitor_info_ptr)[i].monitor =
1450           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->monitor;
1451         (*monitor_info_ptr)[i].stack_depth =
1452           ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(i))->stack_depth;
1453       }
1454     }
1455     *monitor_info_count_ptr = owned_monitor_count;
1456   }
1457 
1458   // clean up.
1459   for (int i = 0; i < owned_monitor_count; i++) {
1460     deallocate((unsigned char*)owned_monitors_list->at(i));
1461   }
1462   delete owned_monitors_list;
1463 
1464   return err;
1465 } /* end GetOwnedMonitorStackDepthInfo */
1466 
1467 
1468 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1469 // monitor_ptr - pre-checked for null
1470 jvmtiError
1471 JvmtiEnv::GetCurrentContendedMonitor(jthread thread, jobject* monitor_ptr) {
1472   JavaThread* current = JavaThread::current();
1473 
1474   *monitor_ptr = nullptr;
1475 
1476   // get contended monitor information with handshake
1477   GetCurrentContendedMonitorClosure op(this, current, monitor_ptr);
1478   JvmtiHandshake::execute(&op, thread);
1479   return op.result();
1480 } /* end GetCurrentContendedMonitor */
1481 
1482 
1483 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1484 // proc - pre-checked for null
1485 // arg - null is a valid value, must be checked
1486 jvmtiError
1487 JvmtiEnv::RunAgentThread(jthread thread, jvmtiStartFunction proc, const void* arg, jint priority) {
1488   JavaThread* current_thread = JavaThread::current();
1489 
1490   JavaThread* java_thread = nullptr;
1491   oop thread_oop = nullptr;
1492   ThreadsListHandle tlh(current_thread);
1493   jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), thread, &java_thread, &thread_oop);
1494   if (err != JVMTI_ERROR_NONE) {
1495     // We got an error code so we don't have a JavaThread *, but
1496     // only return an error from here if we didn't get a valid
1497     // thread_oop.
1498     if (thread_oop == nullptr) {
1499       return err;
1500     }
1501     // We have a valid thread_oop.
1502   }
1503 
1504   if (thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
1505     // No support for virtual threads.
1506     return JVMTI_ERROR_UNSUPPORTED_OPERATION;
1507   }
1508   if (java_thread != nullptr) {
1509     // 'thread' refers to an existing JavaThread.
1510     return JVMTI_ERROR_INVALID_THREAD;
1511   }
1512 
1513   if (priority < JVMTI_THREAD_MIN_PRIORITY || priority > JVMTI_THREAD_MAX_PRIORITY) {
1514     return JVMTI_ERROR_INVALID_PRIORITY;
1515   }
1516 
1517   Handle thread_hndl(current_thread, thread_oop);
1518 
1519   JvmtiAgentThread* new_thread = new JvmtiAgentThread(this, proc, arg);
1520 
1521   // At this point it may be possible that no osthread was created for the
1522   // JavaThread due to lack of resources.
1523   if (new_thread->osthread() == nullptr) {
1524     // The new thread is not known to Thread-SMR yet so we can just delete.
1525     delete new_thread;
1526     return JVMTI_ERROR_OUT_OF_MEMORY;
1527   }
1528 
1529   JavaThread::start_internal_daemon(current_thread, new_thread, thread_hndl,
1530                                     (ThreadPriority)priority);
1531 
1532   return JVMTI_ERROR_NONE;
1533 } /* end RunAgentThread */
1534 
1535   //
1536   // Thread Group functions
1537   //
1538 
1539 // group_count_ptr - pre-checked for null
1540 // groups_ptr - pre-checked for null
1541 jvmtiError
1542 JvmtiEnv::GetTopThreadGroups(jint* group_count_ptr, jthreadGroup** groups_ptr) {
1543   JavaThread* current_thread = JavaThread::current();
1544 
1545   // Only one top level thread group now.
1546   *group_count_ptr = 1;
1547 
1548   // Allocate memory to store global-refs to the thread groups.
1549   // Assume this area is freed by caller.
1550   *groups_ptr = (jthreadGroup *) jvmtiMalloc((sizeof(jthreadGroup)) * (*group_count_ptr));
1551 
1552   NULL_CHECK(*groups_ptr, JVMTI_ERROR_OUT_OF_MEMORY);
1553 
1554   // Convert oop to Handle, then convert Handle to global-ref.
1555   {
1556     HandleMark hm(current_thread);
1557     Handle system_thread_group(current_thread, Universe::system_thread_group());
1558     *groups_ptr[0] = jni_reference(system_thread_group);
1559   }
1560 
1561   return JVMTI_ERROR_NONE;
1562 } /* end GetTopThreadGroups */
1563 
1564 
1565 // info_ptr - pre-checked for null
1566 jvmtiError
1567 JvmtiEnv::GetThreadGroupInfo(jthreadGroup group, jvmtiThreadGroupInfo* info_ptr) {
1568   Thread* current_thread = Thread::current();
1569   ResourceMark rm(current_thread);
1570   HandleMark hm(current_thread);
1571 
1572   Handle group_obj (current_thread, JNIHandles::resolve_external_guard(group));
1573   NULL_CHECK(group_obj(), JVMTI_ERROR_INVALID_THREAD_GROUP);
1574 
1575   const char* name;
1576   Handle parent_group;
1577   bool is_daemon;
1578   ThreadPriority max_priority;
1579 
1580   name         = java_lang_ThreadGroup::name(group_obj());
1581   parent_group = Handle(current_thread, java_lang_ThreadGroup::parent(group_obj()));
1582   is_daemon    = java_lang_ThreadGroup::is_daemon(group_obj());
1583   max_priority = java_lang_ThreadGroup::maxPriority(group_obj());
1584 
1585   info_ptr->is_daemon    = is_daemon;
1586   info_ptr->max_priority = max_priority;
1587   info_ptr->parent       = jni_reference(parent_group);
1588 
1589   if (name != nullptr) {
1590     info_ptr->name = (char*)jvmtiMalloc(strlen(name)+1);
1591     NULL_CHECK(info_ptr->name, JVMTI_ERROR_OUT_OF_MEMORY);
1592     strcpy(info_ptr->name, name);
1593   } else {
1594     info_ptr->name = nullptr;
1595   }
1596 
1597   return JVMTI_ERROR_NONE;
1598 } /* end GetThreadGroupInfo */
1599 
1600 // thread_count_ptr - pre-checked for null
1601 // threads_ptr - pre-checked for null
1602 // group_count_ptr - pre-checked for null
1603 // groups_ptr - pre-checked for null
1604 jvmtiError
1605 JvmtiEnv::GetThreadGroupChildren(jthreadGroup group, jint* thread_count_ptr, jthread** threads_ptr, jint* group_count_ptr, jthreadGroup** groups_ptr) {
1606   jvmtiError err;
1607   JavaThread* current_thread = JavaThread::current();
1608   oop group_obj = JNIHandles::resolve_external_guard(group);
1609   NULL_CHECK(group_obj, JVMTI_ERROR_INVALID_THREAD_GROUP);
1610 
1611   Handle *thread_objs = nullptr;
1612   objArrayHandle group_objs;
1613   jint nthreads = 0;
1614   jint ngroups = 0;
1615   int hidden_threads = 0;
1616 
1617   ResourceMark rm(current_thread);
1618   HandleMark hm(current_thread);
1619 
1620   Handle group_hdl(current_thread, group_obj);
1621 
1622   err = get_live_threads(current_thread, group_hdl, &nthreads, &thread_objs);
1623   if (err != JVMTI_ERROR_NONE) {
1624     return err;
1625   }
1626   err = get_subgroups(current_thread, group_hdl, &ngroups, &group_objs);
1627   if (err != JVMTI_ERROR_NONE) {
1628     return err;
1629   }
1630 
1631   *group_count_ptr  = ngroups;
1632   *thread_count_ptr = nthreads;
1633   *threads_ptr     = new_jthreadArray(nthreads, thread_objs);
1634   *groups_ptr      = new_jthreadGroupArray(ngroups, group_objs);
1635   if (nthreads > 0 && *threads_ptr == nullptr) {
1636     return JVMTI_ERROR_OUT_OF_MEMORY;
1637   }
1638   if (ngroups > 0 && *groups_ptr == nullptr) {
1639     return JVMTI_ERROR_OUT_OF_MEMORY;
1640   }
1641 
1642   return JVMTI_ERROR_NONE;
1643 } /* end GetThreadGroupChildren */
1644 
1645 
1646   //
1647   // Stack Frame functions
1648   //
1649 
1650 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1651 // max_frame_count - pre-checked to be greater than or equal to 0
1652 // frame_buffer - pre-checked for null
1653 // count_ptr - pre-checked for null
1654 jvmtiError
1655 JvmtiEnv::GetStackTrace(jthread thread, jint start_depth, jint max_frame_count, jvmtiFrameInfo* frame_buffer, jint* count_ptr) {
1656   GetStackTraceClosure op(this, start_depth, max_frame_count, frame_buffer, count_ptr);
1657   JvmtiHandshake::execute(&op, thread);
1658   return op.result();
1659 } /* end GetStackTrace */
1660 
1661 
1662 // max_frame_count - pre-checked to be greater than or equal to 0
1663 // stack_info_ptr - pre-checked for null
1664 // thread_count_ptr - pre-checked for null
1665 jvmtiError
1666 JvmtiEnv::GetAllStackTraces(jint max_frame_count, jvmtiStackInfo** stack_info_ptr, jint* thread_count_ptr) {
1667   jvmtiError err = JVMTI_ERROR_NONE;
1668   JavaThread* calling_thread = JavaThread::current();
1669 
1670   // JVMTI get stack traces at safepoint.
1671   VM_GetAllStackTraces op(this, calling_thread, max_frame_count);
1672   VMThread::execute(&op);
1673   *thread_count_ptr = op.final_thread_count();
1674   *stack_info_ptr = op.stack_info();
1675   err = op.result();
1676   return err;
1677 } /* end GetAllStackTraces */
1678 
1679 
1680 // thread_count - pre-checked to be greater than or equal to 0
1681 // thread_list - pre-checked for null
1682 // max_frame_count - pre-checked to be greater than or equal to 0
1683 // stack_info_ptr - pre-checked for null
1684 jvmtiError
1685 JvmtiEnv::GetThreadListStackTraces(jint thread_count, const jthread* thread_list, jint max_frame_count, jvmtiStackInfo** stack_info_ptr) {
1686   jvmtiError err = JVMTI_ERROR_NONE;
1687 
1688   if (thread_count == 1) {
1689     // Use direct handshake if we need to get only one stack trace.
1690     JavaThread *current_thread = JavaThread::current();
1691 
1692     jthread thread = thread_list[0];
1693 
1694     GetSingleStackTraceClosure op(this, current_thread, thread, max_frame_count);
1695     JvmtiHandshake::execute(&op, thread);
1696     err = op.result();
1697     if (err == JVMTI_ERROR_NONE) {
1698       *stack_info_ptr = op.stack_info();
1699     }
1700   } else {
1701     JvmtiVTMSTransitionDisabler disabler;
1702 
1703     // JVMTI get stack traces at safepoint.
1704     VM_GetThreadListStackTraces op(this, thread_count, thread_list, max_frame_count);
1705     VMThread::execute(&op);
1706     err = op.result();
1707     if (err == JVMTI_ERROR_NONE) {
1708       *stack_info_ptr = op.stack_info();
1709     }
1710   }
1711   return err;
1712 } /* end GetThreadListStackTraces */
1713 
1714 
1715 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1716 // count_ptr - pre-checked for null
1717 jvmtiError
1718 JvmtiEnv::GetFrameCount(jthread thread, jint* count_ptr) {
1719   GetFrameCountClosure op(this, count_ptr);
1720   JvmtiHandshake::execute(&op, thread);
1721   return op.result();
1722 } /* end GetFrameCount */
1723 
1724 
1725 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1726 jvmtiError
1727 JvmtiEnv::PopFrame(jthread thread) {
1728   JavaThread* current_thread = JavaThread::current();
1729   HandleMark hm(current_thread);
1730 
1731   if (thread == nullptr) {
1732     return JVMTI_ERROR_INVALID_THREAD;
1733   }
1734   JvmtiVTMSTransitionDisabler disabler(thread);
1735   ThreadsListHandle tlh(current_thread);
1736 
1737   JavaThread* java_thread = nullptr;
1738   oop thread_obj = nullptr;
1739   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
1740   Handle thread_handle(current_thread, thread_obj);
1741 
1742   if (err != JVMTI_ERROR_NONE) {
1743     return err;
1744   }
1745   bool self = java_thread == current_thread;
1746 
1747   err = check_non_suspended_or_opaque_frame(java_thread, thread_obj, self);
1748   if (err != JVMTI_ERROR_NONE) {
1749     return err;
1750   }
1751 
1752   // retrieve or create the state
1753   JvmtiThreadState* state = JvmtiThreadState::state_for(java_thread);
1754   if (state == nullptr) {
1755     return JVMTI_ERROR_THREAD_NOT_ALIVE;
1756   }
1757 
1758   // Eagerly reallocate scalar replaced objects.
1759   EscapeBarrier eb(true, current_thread, java_thread);
1760   if (!eb.deoptimize_objects(1)) {
1761     // Reallocation of scalar replaced objects failed -> return with error
1762     return JVMTI_ERROR_OUT_OF_MEMORY;
1763   }
1764 
1765   MutexLocker mu(JvmtiThreadState_lock);
1766   UpdateForPopTopFrameClosure op(state);
1767   JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1768   return op.result();
1769 } /* end PopFrame */
1770 
1771 
1772 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1773 // depth - pre-checked as non-negative
1774 // method_ptr - pre-checked for null
1775 // location_ptr - pre-checked for null
1776 jvmtiError
1777 JvmtiEnv::GetFrameLocation(jthread thread, jint depth, jmethodID* method_ptr, jlocation* location_ptr) {
1778   GetFrameLocationClosure op(this, depth, method_ptr, location_ptr);
1779   JvmtiHandshake::execute(&op, thread);
1780   return op.result();
1781 } /* end GetFrameLocation */
1782 
1783 
1784 // Threads_lock NOT held, java_thread not protected by lock
1785 // depth - pre-checked as non-negative
1786 jvmtiError
1787 JvmtiEnv::NotifyFramePop(jthread thread, jint depth) {
1788   ResourceMark rm;
1789   JvmtiVTMSTransitionDisabler disabler(thread);
1790   JavaThread* current = JavaThread::current();
1791   ThreadsListHandle tlh(current);
1792 
1793   JavaThread* java_thread = nullptr;
1794   oop thread_obj = nullptr;
1795   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current, &java_thread, &thread_obj);
1796   if (err != JVMTI_ERROR_NONE) {
1797     return err;
1798   }
1799 
1800   HandleMark hm(current);
1801   Handle thread_handle(current, thread_obj);
1802   JvmtiThreadState *state = JvmtiThreadState::state_for(java_thread, thread_handle);
1803   if (state == nullptr) {
1804     return JVMTI_ERROR_THREAD_NOT_ALIVE;
1805   }
1806 
1807   SetOrClearFramePopClosure op(this, state, true /* set */, depth);
1808   MutexLocker mu(current, JvmtiThreadState_lock);
1809   JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1810   return op.result();
1811 } /* end NotifyFramePop */
1812 
1813 // Threads_lock NOT held, java_thread not protected by lock
1814 jvmtiError
1815 JvmtiEnv::ClearAllFramePops(jthread thread) {
1816   ResourceMark rm;
1817   JvmtiVTMSTransitionDisabler disabler(thread);
1818   JavaThread* current = JavaThread::current();
1819   ThreadsListHandle tlh(current);
1820 
1821   JavaThread* java_thread = nullptr;
1822   oop thread_obj = nullptr;
1823   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current, &java_thread, &thread_obj);
1824   if (err != JVMTI_ERROR_NONE) {
1825     return err;
1826   }
1827 
1828   HandleMark hm(current);
1829   Handle thread_handle(current, thread_obj);
1830   JvmtiThreadState *state = JvmtiThreadState::state_for(java_thread, thread_handle);
1831   if (state == nullptr) {
1832     return JVMTI_ERROR_THREAD_NOT_ALIVE;
1833   }
1834 
1835   SetOrClearFramePopClosure op(this, state, false /* clear all frame pops*/);
1836   MutexLocker mu(current, JvmtiThreadState_lock);
1837   JvmtiHandshake::execute(&op, &tlh, java_thread, thread_handle);
1838   return op.result();
1839 } /* end ClearAllFramePops */
1840 
1841   //
1842   // Force Early Return functions
1843   //
1844 
1845 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1846 jvmtiError
1847 JvmtiEnv::ForceEarlyReturnObject(jthread thread, jobject value) {
1848   jvalue val;
1849   val.l = value;
1850   return force_early_return(thread, val, atos);
1851 } /* end ForceEarlyReturnObject */
1852 
1853 
1854 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1855 jvmtiError
1856 JvmtiEnv::ForceEarlyReturnInt(jthread thread, jint value) {
1857   jvalue val;
1858   val.i = value;
1859   return force_early_return(thread, val, itos);
1860 } /* end ForceEarlyReturnInt */
1861 
1862 
1863 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1864 jvmtiError
1865 JvmtiEnv::ForceEarlyReturnLong(jthread thread, jlong value) {
1866   jvalue val;
1867   val.j = value;
1868   return force_early_return(thread, val, ltos);
1869 } /* end ForceEarlyReturnLong */
1870 
1871 
1872 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1873 jvmtiError
1874 JvmtiEnv::ForceEarlyReturnFloat(jthread thread, jfloat value) {
1875   jvalue val;
1876   val.f = value;
1877   return force_early_return(thread, val, ftos);
1878 } /* end ForceEarlyReturnFloat */
1879 
1880 
1881 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1882 jvmtiError
1883 JvmtiEnv::ForceEarlyReturnDouble(jthread thread, jdouble value) {
1884   jvalue val;
1885   val.d = value;
1886   return force_early_return(thread, val, dtos);
1887 } /* end ForceEarlyReturnDouble */
1888 
1889 
1890 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
1891 jvmtiError
1892 JvmtiEnv::ForceEarlyReturnVoid(jthread thread) {
1893   jvalue val;
1894   val.j = 0L;
1895   return force_early_return(thread, val, vtos);
1896 } /* end ForceEarlyReturnVoid */
1897 
1898 
1899   //
1900   // Heap functions
1901   //
1902 
1903 // klass - null is a valid value, must be checked
1904 // initial_object - null is a valid value, must be checked
1905 // callbacks - pre-checked for null
1906 // user_data - null is a valid value, must be checked
1907 jvmtiError
1908 JvmtiEnv::FollowReferences(jint heap_filter, jclass klass, jobject initial_object, const jvmtiHeapCallbacks* callbacks, const void* user_data) {
1909   // check klass if provided
1910   Klass* k = nullptr;
1911   if (klass != nullptr) {
1912     oop k_mirror = JNIHandles::resolve_external_guard(klass);
1913     if (k_mirror == nullptr) {
1914       return JVMTI_ERROR_INVALID_CLASS;
1915     }
1916     if (java_lang_Class::is_primitive(k_mirror)) {
1917       return JVMTI_ERROR_NONE;
1918     }
1919     k = java_lang_Class::as_Klass(k_mirror);
1920     if (klass == nullptr) {
1921       return JVMTI_ERROR_INVALID_CLASS;
1922     }
1923   }
1924 
1925   if (initial_object != nullptr) {
1926     oop init_obj = JNIHandles::resolve_external_guard(initial_object);
1927     if (init_obj == nullptr) {
1928       return JVMTI_ERROR_INVALID_OBJECT;
1929     }
1930   }
1931 
1932   Thread *thread = Thread::current();
1933   HandleMark hm(thread);
1934 
1935   TraceTime t("FollowReferences", TRACETIME_LOG(Debug, jvmti, objecttagging));
1936   JvmtiTagMap::tag_map_for(this)->follow_references(heap_filter, k, initial_object, callbacks, user_data);
1937   return JVMTI_ERROR_NONE;
1938 } /* end FollowReferences */
1939 
1940 
1941 // klass - null is a valid value, must be checked
1942 // callbacks - pre-checked for null
1943 // user_data - null is a valid value, must be checked
1944 jvmtiError
1945 JvmtiEnv::IterateThroughHeap(jint heap_filter, jclass klass, const jvmtiHeapCallbacks* callbacks, const void* user_data) {
1946   // check klass if provided
1947   Klass* k = nullptr;
1948   if (klass != nullptr) {
1949     oop k_mirror = JNIHandles::resolve_external_guard(klass);
1950     if (k_mirror == nullptr) {
1951       return JVMTI_ERROR_INVALID_CLASS;
1952     }
1953     if (java_lang_Class::is_primitive(k_mirror)) {
1954       return JVMTI_ERROR_NONE;
1955     }
1956     k = java_lang_Class::as_Klass(k_mirror);
1957     if (k == nullptr) {
1958       return JVMTI_ERROR_INVALID_CLASS;
1959     }
1960   }
1961 
1962   TraceTime t("IterateThroughHeap", TRACETIME_LOG(Debug, jvmti, objecttagging));
1963   JvmtiTagMap::tag_map_for(this)->iterate_through_heap(heap_filter, k, callbacks, user_data);
1964   return JVMTI_ERROR_NONE;
1965 } /* end IterateThroughHeap */
1966 
1967 
1968 // tag_ptr - pre-checked for null
1969 jvmtiError
1970 JvmtiEnv::GetTag(jobject object, jlong* tag_ptr) {
1971   oop o = JNIHandles::resolve_external_guard(object);
1972   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
1973   *tag_ptr = JvmtiTagMap::tag_map_for(this)->get_tag(object);
1974   return JVMTI_ERROR_NONE;
1975 } /* end GetTag */
1976 
1977 
1978 jvmtiError
1979 JvmtiEnv::SetTag(jobject object, jlong tag) {
1980   oop o = JNIHandles::resolve_external_guard(object);
1981   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
1982   JvmtiTagMap::tag_map_for(this)->set_tag(object, tag);
1983   return JVMTI_ERROR_NONE;
1984 } /* end SetTag */
1985 
1986 
1987 // tag_count - pre-checked to be greater than or equal to 0
1988 // tags - pre-checked for null
1989 // count_ptr - pre-checked for null
1990 // object_result_ptr - null is a valid value, must be checked
1991 // tag_result_ptr - null is a valid value, must be checked
1992 jvmtiError
1993 JvmtiEnv::GetObjectsWithTags(jint tag_count, const jlong* tags, jint* count_ptr, jobject** object_result_ptr, jlong** tag_result_ptr) {
1994   TraceTime t("GetObjectsWithTags", TRACETIME_LOG(Debug, jvmti, objecttagging));
1995   return JvmtiTagMap::tag_map_for(this)->get_objects_with_tags((jlong*)tags, tag_count, count_ptr, object_result_ptr, tag_result_ptr);
1996 } /* end GetObjectsWithTags */
1997 
1998 
1999 jvmtiError
2000 JvmtiEnv::ForceGarbageCollection() {
2001   Universe::heap()->collect(GCCause::_jvmti_force_gc);
2002   return JVMTI_ERROR_NONE;
2003 } /* end ForceGarbageCollection */
2004 
2005 
2006   //
2007   // Heap (1.0) functions
2008   //
2009 
2010 // object_reference_callback - pre-checked for null
2011 // user_data - null is a valid value, must be checked
2012 jvmtiError
2013 JvmtiEnv::IterateOverObjectsReachableFromObject(jobject object, jvmtiObjectReferenceCallback object_reference_callback, const void* user_data) {
2014   oop o = JNIHandles::resolve_external_guard(object);
2015   NULL_CHECK(o, JVMTI_ERROR_INVALID_OBJECT);
2016   JvmtiTagMap::tag_map_for(this)->iterate_over_objects_reachable_from_object(object, object_reference_callback, user_data);
2017   return JVMTI_ERROR_NONE;
2018 } /* end IterateOverObjectsReachableFromObject */
2019 
2020 
2021 // heap_root_callback - null is a valid value, must be checked
2022 // stack_ref_callback - null is a valid value, must be checked
2023 // object_ref_callback - null is a valid value, must be checked
2024 // user_data - null is a valid value, must be checked
2025 jvmtiError
2026 JvmtiEnv::IterateOverReachableObjects(jvmtiHeapRootCallback heap_root_callback, jvmtiStackReferenceCallback stack_ref_callback, jvmtiObjectReferenceCallback object_ref_callback, const void* user_data) {
2027   TraceTime t("IterateOverReachableObjects", TRACETIME_LOG(Debug, jvmti, objecttagging));
2028   JvmtiTagMap::tag_map_for(this)->iterate_over_reachable_objects(heap_root_callback, stack_ref_callback, object_ref_callback, user_data);
2029   return JVMTI_ERROR_NONE;
2030 } /* end IterateOverReachableObjects */
2031 
2032 
2033 // heap_object_callback - pre-checked for null
2034 // user_data - null is a valid value, must be checked
2035 jvmtiError
2036 JvmtiEnv::IterateOverHeap(jvmtiHeapObjectFilter object_filter, jvmtiHeapObjectCallback heap_object_callback, const void* user_data) {
2037   TraceTime t("IterateOverHeap", TRACETIME_LOG(Debug, jvmti, objecttagging));
2038   Thread *thread = Thread::current();
2039   HandleMark hm(thread);
2040   JvmtiTagMap::tag_map_for(this)->iterate_over_heap(object_filter, nullptr, heap_object_callback, user_data);
2041   return JVMTI_ERROR_NONE;
2042 } /* end IterateOverHeap */
2043 
2044 
2045 // k_mirror - may be primitive, this must be checked
2046 // heap_object_callback - pre-checked for null
2047 // user_data - null is a valid value, must be checked
2048 jvmtiError
2049 JvmtiEnv::IterateOverInstancesOfClass(oop k_mirror, jvmtiHeapObjectFilter object_filter, jvmtiHeapObjectCallback heap_object_callback, const void* user_data) {
2050   if (java_lang_Class::is_primitive(k_mirror)) {
2051     // DO PRIMITIVE CLASS PROCESSING
2052     return JVMTI_ERROR_NONE;
2053   }
2054   Klass* klass = java_lang_Class::as_Klass(k_mirror);
2055   if (klass == nullptr) {
2056     return JVMTI_ERROR_INVALID_CLASS;
2057   }
2058   TraceTime t("IterateOverInstancesOfClass", TRACETIME_LOG(Debug, jvmti, objecttagging));
2059   JvmtiTagMap::tag_map_for(this)->iterate_over_heap(object_filter, klass, heap_object_callback, user_data);
2060   return JVMTI_ERROR_NONE;
2061 } /* end IterateOverInstancesOfClass */
2062 
2063 
2064   //
2065   // Local Variable functions
2066   //
2067 
2068 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2069 // depth - pre-checked as non-negative
2070 // value_ptr - pre-checked for null
2071 jvmtiError
2072 JvmtiEnv::GetLocalObject(jthread thread, jint depth, jint slot, jobject* value_ptr) {
2073   JavaThread* current_thread = JavaThread::current();
2074   // rm object is created to clean up the javaVFrame created in
2075   // doit_prologue(), but after doit() is finished with it.
2076   ResourceMark rm(current_thread);
2077   HandleMark hm(current_thread);
2078   JvmtiVTMSTransitionDisabler disabler(thread);
2079   ThreadsListHandle tlh(current_thread);
2080 
2081   JavaThread* java_thread = nullptr;
2082   oop thread_obj = nullptr;
2083   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2084   if (err != JVMTI_ERROR_NONE) {
2085     return err;
2086   }
2087   bool self = is_JavaThread_current(java_thread, thread_obj);
2088 
2089   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2090     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2091                                      current_thread, depth, slot, self);
2092     VMThread::execute(&op);
2093     err = op.result();
2094     if (err == JVMTI_ERROR_NONE) {
2095       *value_ptr = op.value().l;
2096     }
2097   } else {
2098     // Support for ordinary threads
2099     VM_GetOrSetLocal op(java_thread, current_thread, depth, slot, self);
2100     VMThread::execute(&op);
2101     err = op.result();
2102     if (err == JVMTI_ERROR_NONE) {
2103       *value_ptr = op.value().l;
2104     }
2105   }
2106   return err;
2107 } /* end GetLocalObject */
2108 
2109 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2110 // depth - pre-checked as non-negative
2111 // value - pre-checked for null
2112 jvmtiError
2113 JvmtiEnv::GetLocalInstance(jthread thread, jint depth, jobject* value_ptr){
2114   JavaThread* current_thread = JavaThread::current();
2115   // rm object is created to clean up the javaVFrame created in
2116   // doit_prologue(), but after doit() is finished with it.
2117   ResourceMark rm(current_thread);
2118   HandleMark hm(current_thread);
2119   JvmtiVTMSTransitionDisabler disabler(thread);
2120   ThreadsListHandle tlh(current_thread);
2121 
2122   JavaThread* java_thread = nullptr;
2123   oop thread_obj = nullptr;
2124   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2125   if (err != JVMTI_ERROR_NONE) {
2126     return err;
2127   }
2128   bool self = is_JavaThread_current(java_thread, thread_obj);
2129 
2130   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2131     VM_VirtualThreadGetReceiver op(this, Handle(current_thread, thread_obj),
2132                                    current_thread, depth, self);
2133     VMThread::execute(&op);
2134     err = op.result();
2135     if (err == JVMTI_ERROR_NONE) {
2136       *value_ptr = op.value().l;
2137     }
2138   } else {
2139     // Support for ordinary threads
2140     VM_GetReceiver op(java_thread, current_thread, depth, self);
2141     VMThread::execute(&op);
2142     err = op.result();
2143     if (err == JVMTI_ERROR_NONE) {
2144       *value_ptr = op.value().l;
2145     }
2146   }
2147   return err;
2148 } /* end GetLocalInstance */
2149 
2150 
2151 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2152 // depth - pre-checked as non-negative
2153 // value_ptr - pre-checked for null
2154 jvmtiError
2155 JvmtiEnv::GetLocalInt(jthread thread, jint depth, jint slot, jint* value_ptr) {
2156   JavaThread* current_thread = JavaThread::current();
2157   // rm object is created to clean up the javaVFrame created in
2158   // doit_prologue(), but after doit() is finished with it.
2159   ResourceMark rm(current_thread);
2160   HandleMark hm(current_thread);
2161   JvmtiVTMSTransitionDisabler disabler(thread);
2162   ThreadsListHandle tlh(current_thread);
2163 
2164   JavaThread* java_thread = nullptr;
2165   oop thread_obj = nullptr;
2166   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2167   if (err != JVMTI_ERROR_NONE) {
2168     return err;
2169   }
2170   bool self = is_JavaThread_current(java_thread, thread_obj);
2171 
2172   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2173     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2174                                      depth, slot, T_INT, self);
2175     VMThread::execute(&op);
2176     err = op.result();
2177     if (err == JVMTI_ERROR_NONE) {
2178       *value_ptr = op.value().i;
2179     }
2180   } else {
2181     // Support for ordinary threads
2182     VM_GetOrSetLocal op(java_thread, depth, slot, T_INT, self);
2183     VMThread::execute(&op);
2184     err = op.result();
2185     if (err == JVMTI_ERROR_NONE) {
2186       *value_ptr = op.value().i;
2187     }
2188   }
2189   return err;
2190 } /* end GetLocalInt */
2191 
2192 
2193 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2194 // depth - pre-checked as non-negative
2195 // value_ptr - pre-checked for null
2196 jvmtiError
2197 JvmtiEnv::GetLocalLong(jthread thread, jint depth, jint slot, jlong* value_ptr) {
2198   JavaThread* current_thread = JavaThread::current();
2199   // rm object is created to clean up the javaVFrame created in
2200   // doit_prologue(), but after doit() is finished with it.
2201   ResourceMark rm(current_thread);
2202   HandleMark hm(current_thread);
2203   JvmtiVTMSTransitionDisabler disabler(thread);
2204   ThreadsListHandle tlh(current_thread);
2205 
2206   JavaThread* java_thread = nullptr;
2207   oop thread_obj = nullptr;
2208   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2209   if (err != JVMTI_ERROR_NONE) {
2210     return err;
2211   }
2212   bool self = is_JavaThread_current(java_thread, thread_obj);
2213 
2214   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2215     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2216                                      depth, slot, T_LONG, self);
2217     VMThread::execute(&op);
2218     err = op.result();
2219     if (err == JVMTI_ERROR_NONE) {
2220       *value_ptr = op.value().j;
2221     }
2222   } else {
2223     // Support for ordinary threads
2224     VM_GetOrSetLocal op(java_thread, depth, slot, T_LONG, self);
2225     VMThread::execute(&op);
2226     err = op.result();
2227     if (err == JVMTI_ERROR_NONE) {
2228       *value_ptr = op.value().j;
2229     }
2230   }
2231   return err;
2232 } /* end GetLocalLong */
2233 
2234 
2235 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2236 // depth - pre-checked as non-negative
2237 // value_ptr - pre-checked for null
2238 jvmtiError
2239 JvmtiEnv::GetLocalFloat(jthread thread, jint depth, jint slot, jfloat* value_ptr) {
2240   JavaThread* current_thread = JavaThread::current();
2241   // rm object is created to clean up the javaVFrame created in
2242   // doit_prologue(), but after doit() is finished with it.
2243   ResourceMark rm(current_thread);
2244   HandleMark hm(current_thread);
2245   JvmtiVTMSTransitionDisabler disabler(thread);
2246   ThreadsListHandle tlh(current_thread);
2247 
2248   JavaThread* java_thread = nullptr;
2249   oop thread_obj = nullptr;
2250   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2251   if (err != JVMTI_ERROR_NONE) {
2252     return err;
2253   }
2254   bool self = is_JavaThread_current(java_thread, thread_obj);
2255 
2256   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2257     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2258                                      depth, slot, T_FLOAT, self);
2259     VMThread::execute(&op);
2260     err = op.result();
2261     if (err == JVMTI_ERROR_NONE) {
2262       *value_ptr = op.value().f;
2263     }
2264   } else {
2265     // Support for ordinary threads
2266     VM_GetOrSetLocal op(java_thread, depth, slot, T_FLOAT, self);
2267     VMThread::execute(&op);
2268     err = op.result();
2269     if (err == JVMTI_ERROR_NONE) {
2270       *value_ptr = op.value().f;
2271     }
2272   }
2273   return err;
2274 } /* end GetLocalFloat */
2275 
2276 
2277 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2278 // depth - pre-checked as non-negative
2279 // value_ptr - pre-checked for null
2280 jvmtiError
2281 JvmtiEnv::GetLocalDouble(jthread thread, jint depth, jint slot, jdouble* value_ptr) {
2282   JavaThread* current_thread = JavaThread::current();
2283   // rm object is created to clean up the javaVFrame created in
2284   // doit_prologue(), but after doit() is finished with it.
2285   ResourceMark rm(current_thread);
2286   HandleMark hm(current_thread);
2287   JvmtiVTMSTransitionDisabler disabler(thread);
2288   ThreadsListHandle tlh(current_thread);
2289 
2290   JavaThread* java_thread = nullptr;
2291   oop thread_obj = nullptr;
2292   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2293   if (err != JVMTI_ERROR_NONE) {
2294     return err;
2295   }
2296   bool self = is_JavaThread_current(java_thread, thread_obj);
2297 
2298   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2299     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2300                                      depth, slot, T_DOUBLE, self);
2301     VMThread::execute(&op);
2302     err = op.result();
2303     if (err == JVMTI_ERROR_NONE) {
2304       *value_ptr = op.value().d;
2305     }
2306   } else {
2307     // Support for ordinary threads
2308     VM_GetOrSetLocal op(java_thread, depth, slot, T_DOUBLE, self);
2309     VMThread::execute(&op);
2310     err = op.result();
2311     if (err == JVMTI_ERROR_NONE) {
2312       *value_ptr = op.value().d;
2313     }
2314   }
2315   return err;
2316 } /* end GetLocalDouble */
2317 
2318 
2319 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2320 // depth - pre-checked as non-negative
2321 jvmtiError
2322 JvmtiEnv::SetLocalObject(jthread thread, jint depth, jint slot, jobject value) {
2323   JavaThread* current_thread = JavaThread::current();
2324   // rm object is created to clean up the javaVFrame created in
2325   // doit_prologue(), but after doit() is finished with it.
2326   ResourceMark rm(current_thread);
2327   HandleMark hm(current_thread);
2328   JvmtiVTMSTransitionDisabler disabler(thread);
2329   ThreadsListHandle tlh(current_thread);
2330 
2331   JavaThread* java_thread = nullptr;
2332   oop thread_obj = nullptr;
2333   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2334   if (err != JVMTI_ERROR_NONE) {
2335     return err;
2336   }
2337   bool self = is_JavaThread_current(java_thread, thread_obj);
2338   jvalue val;
2339   val.l = value;
2340 
2341   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2342     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2343                                      depth, slot, T_OBJECT, val, self);
2344     VMThread::execute(&op);
2345     err = op.result();
2346   } else {
2347     // Support for ordinary threads
2348     VM_GetOrSetLocal op(java_thread, depth, slot, T_OBJECT, val, self);
2349     VMThread::execute(&op);
2350     err = op.result();
2351   }
2352   return err;
2353 } /* end SetLocalObject */
2354 
2355 
2356 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2357 // depth - pre-checked as non-negative
2358 jvmtiError
2359 JvmtiEnv::SetLocalInt(jthread thread, jint depth, jint slot, jint value) {
2360   JavaThread* current_thread = JavaThread::current();
2361   // rm object is created to clean up the javaVFrame created in
2362   // doit_prologue(), but after doit() is finished with it.
2363   ResourceMark rm(current_thread);
2364   HandleMark hm(current_thread);
2365   JvmtiVTMSTransitionDisabler disabler(thread);
2366   ThreadsListHandle tlh(current_thread);
2367 
2368   JavaThread* java_thread = nullptr;
2369   oop thread_obj = nullptr;
2370   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2371   if (err != JVMTI_ERROR_NONE) {
2372     return err;
2373   }
2374   bool self = is_JavaThread_current(java_thread, thread_obj);
2375   jvalue val;
2376   val.i = value;
2377 
2378   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2379     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2380                                      depth, slot, T_INT, val, self);
2381     VMThread::execute(&op);
2382     err = op.result();
2383   } else {
2384     // Support for ordinary threads
2385     VM_GetOrSetLocal op(java_thread, depth, slot, T_INT, val, self);
2386     VMThread::execute(&op);
2387     err = op.result();
2388   }
2389   return err;
2390 } /* end SetLocalInt */
2391 
2392 
2393 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2394 // depth - pre-checked as non-negative
2395 jvmtiError
2396 JvmtiEnv::SetLocalLong(jthread thread, jint depth, jint slot, jlong value) {
2397   JavaThread* current_thread = JavaThread::current();
2398   // rm object is created to clean up the javaVFrame created in
2399   // doit_prologue(), but after doit() is finished with it.
2400   ResourceMark rm(current_thread);
2401   HandleMark hm(current_thread);
2402   JvmtiVTMSTransitionDisabler disabler(thread);
2403   ThreadsListHandle tlh(current_thread);
2404 
2405   JavaThread* java_thread = nullptr;
2406   oop thread_obj = nullptr;
2407   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2408   if (err != JVMTI_ERROR_NONE) {
2409     return err;
2410   }
2411   bool self = is_JavaThread_current(java_thread, thread_obj);
2412   jvalue val;
2413   val.j = value;
2414 
2415   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2416     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2417                                      depth, slot, T_LONG, val, self);
2418     VMThread::execute(&op);
2419     err = op.result();
2420   } else {
2421     // Support for ordinary threads
2422     VM_GetOrSetLocal op(java_thread, depth, slot, T_LONG, val, self);
2423     VMThread::execute(&op);
2424     err = op.result();
2425   }
2426   return err;
2427 } /* end SetLocalLong */
2428 
2429 
2430 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2431 // depth - pre-checked as non-negative
2432 jvmtiError
2433 JvmtiEnv::SetLocalFloat(jthread thread, jint depth, jint slot, jfloat value) {
2434   JavaThread* current_thread = JavaThread::current();
2435   // rm object is created to clean up the javaVFrame created in
2436   // doit_prologue(), but after doit() is finished with it.
2437   ResourceMark rm(current_thread);
2438   HandleMark hm(current_thread);
2439   JvmtiVTMSTransitionDisabler disabler(thread);
2440   ThreadsListHandle tlh(current_thread);
2441 
2442   JavaThread* java_thread = nullptr;
2443   oop thread_obj = nullptr;
2444   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2445   if (err != JVMTI_ERROR_NONE) {
2446     return err;
2447   }
2448   bool self = is_JavaThread_current(java_thread, thread_obj);
2449   jvalue val;
2450   val.f = value;
2451 
2452   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2453     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2454                                      depth, slot, T_FLOAT, val, self);
2455     VMThread::execute(&op);
2456     err = op.result();
2457   } else {
2458     // Support for ordinary threads
2459     VM_GetOrSetLocal op(java_thread, depth, slot, T_FLOAT, val, self);
2460     VMThread::execute(&op);
2461     err = op.result();
2462   }
2463   return err;
2464 } /* end SetLocalFloat */
2465 
2466 
2467 // thread - NOT protected by ThreadsListHandle and NOT pre-checked
2468 // depth - pre-checked as non-negative
2469 jvmtiError
2470 JvmtiEnv::SetLocalDouble(jthread thread, jint depth, jint slot, jdouble value) {
2471   JavaThread* current_thread = JavaThread::current();
2472   // rm object is created to clean up the javaVFrame created in
2473   // doit_prologue(), but after doit() is finished with it.
2474   ResourceMark rm(current_thread);
2475   HandleMark hm(current_thread);
2476   JvmtiVTMSTransitionDisabler disabler(thread);
2477   ThreadsListHandle tlh(current_thread);
2478 
2479   JavaThread* java_thread = nullptr;
2480   oop thread_obj = nullptr;
2481   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_obj);
2482   if (err != JVMTI_ERROR_NONE) {
2483     return err;
2484   }
2485   bool self = is_JavaThread_current(java_thread, thread_obj);
2486   jvalue val;
2487   val.d = value;
2488 
2489   if (java_lang_VirtualThread::is_instance(thread_obj)) {
2490     VM_VirtualThreadGetOrSetLocal op(this, Handle(current_thread, thread_obj),
2491                                      depth, slot, T_DOUBLE, val, self);
2492     VMThread::execute(&op);
2493     err = op.result();
2494   } else {
2495     // Support for ordinary threads
2496     VM_GetOrSetLocal op(java_thread, depth, slot, T_DOUBLE, val, self);
2497     VMThread::execute(&op);
2498     err = op.result();
2499   }
2500   return err;
2501 } /* end SetLocalDouble */
2502 
2503 
2504   //
2505   // Breakpoint functions
2506   //
2507 
2508 // method - pre-checked for validity, but may be null meaning obsolete method
2509 jvmtiError
2510 JvmtiEnv::SetBreakpoint(Method* method, jlocation location) {
2511   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
2512   if (location < 0) {   // simple invalid location check first
2513     return JVMTI_ERROR_INVALID_LOCATION;
2514   }
2515   // verify that the breakpoint is not past the end of the method
2516   if (location >= (jlocation) method->code_size()) {
2517     return JVMTI_ERROR_INVALID_LOCATION;
2518   }
2519 
2520   ResourceMark rm;
2521   JvmtiBreakpoint bp(method, location);
2522   JvmtiBreakpoints& jvmti_breakpoints = JvmtiCurrentBreakpoints::get_jvmti_breakpoints();
2523   if (jvmti_breakpoints.set(bp) == JVMTI_ERROR_DUPLICATE)
2524     return JVMTI_ERROR_DUPLICATE;
2525 
2526   if (TraceJVMTICalls) {
2527     jvmti_breakpoints.print();
2528   }
2529 
2530   return JVMTI_ERROR_NONE;
2531 } /* end SetBreakpoint */
2532 
2533 
2534 // method - pre-checked for validity, but may be null meaning obsolete method
2535 jvmtiError
2536 JvmtiEnv::ClearBreakpoint(Method* method, jlocation location) {
2537   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
2538 
2539   if (location < 0) {   // simple invalid location check first
2540     return JVMTI_ERROR_INVALID_LOCATION;
2541   }
2542 
2543   // verify that the breakpoint is not past the end of the method
2544   if (location >= (jlocation) method->code_size()) {
2545     return JVMTI_ERROR_INVALID_LOCATION;
2546   }
2547 
2548   JvmtiBreakpoint bp(method, location);
2549 
2550   JvmtiBreakpoints& jvmti_breakpoints = JvmtiCurrentBreakpoints::get_jvmti_breakpoints();
2551   if (jvmti_breakpoints.clear(bp) == JVMTI_ERROR_NOT_FOUND)
2552     return JVMTI_ERROR_NOT_FOUND;
2553 
2554   if (TraceJVMTICalls) {
2555     jvmti_breakpoints.print();
2556   }
2557 
2558   return JVMTI_ERROR_NONE;
2559 } /* end ClearBreakpoint */
2560 
2561 
2562   //
2563   // Watched Field functions
2564   //
2565 
2566 jvmtiError
2567 JvmtiEnv::SetFieldAccessWatch(fieldDescriptor* fdesc_ptr) {
2568   JvmtiVTMSTransitionDisabler disabler;
2569   // make sure we haven't set this watch before
2570   if (fdesc_ptr->is_field_access_watched()) return JVMTI_ERROR_DUPLICATE;
2571   fdesc_ptr->set_is_field_access_watched(true);
2572 
2573   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_ACCESS, true);
2574 
2575   return JVMTI_ERROR_NONE;
2576 } /* end SetFieldAccessWatch */
2577 
2578 
2579 jvmtiError
2580 JvmtiEnv::ClearFieldAccessWatch(fieldDescriptor* fdesc_ptr) {
2581   JvmtiVTMSTransitionDisabler disabler;
2582   // make sure we have a watch to clear
2583   if (!fdesc_ptr->is_field_access_watched()) return JVMTI_ERROR_NOT_FOUND;
2584   fdesc_ptr->set_is_field_access_watched(false);
2585 
2586   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_ACCESS, false);
2587 
2588   return JVMTI_ERROR_NONE;
2589 } /* end ClearFieldAccessWatch */
2590 
2591 
2592 jvmtiError
2593 JvmtiEnv::SetFieldModificationWatch(fieldDescriptor* fdesc_ptr) {
2594   JvmtiVTMSTransitionDisabler disabler;
2595   // make sure we haven't set this watch before
2596   if (fdesc_ptr->is_field_modification_watched()) return JVMTI_ERROR_DUPLICATE;
2597   fdesc_ptr->set_is_field_modification_watched(true);
2598 
2599   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_MODIFICATION, true);
2600 
2601   return JVMTI_ERROR_NONE;
2602 } /* end SetFieldModificationWatch */
2603 
2604 
2605 jvmtiError
2606 JvmtiEnv::ClearFieldModificationWatch(fieldDescriptor* fdesc_ptr) {
2607   JvmtiVTMSTransitionDisabler disabler;
2608    // make sure we have a watch to clear
2609   if (!fdesc_ptr->is_field_modification_watched()) return JVMTI_ERROR_NOT_FOUND;
2610   fdesc_ptr->set_is_field_modification_watched(false);
2611 
2612   JvmtiEventController::change_field_watch(JVMTI_EVENT_FIELD_MODIFICATION, false);
2613 
2614   return JVMTI_ERROR_NONE;
2615 } /* end ClearFieldModificationWatch */
2616 
2617   //
2618   // Class functions
2619   //
2620 
2621 
2622 // k_mirror - may be primitive, this must be checked
2623 // signature_ptr - null is a valid value, must be checked
2624 // generic_ptr - null is a valid value, must be checked
2625 jvmtiError
2626 JvmtiEnv::GetClassSignature(oop k_mirror, char** signature_ptr, char** generic_ptr) {
2627   ResourceMark rm;
2628   bool isPrimitive = java_lang_Class::is_primitive(k_mirror);
2629   Klass* k = nullptr;
2630   if (!isPrimitive) {
2631     k = java_lang_Class::as_Klass(k_mirror);
2632     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2633   }
2634   if (signature_ptr != nullptr) {
2635     char* result = nullptr;
2636     if (isPrimitive) {
2637       char tchar = type2char(java_lang_Class::primitive_type(k_mirror));
2638       result = (char*) jvmtiMalloc(2);
2639       result[0] = tchar;
2640       result[1] = '\0';
2641     } else {
2642       const char* class_sig = k->signature_name();
2643       result = (char *) jvmtiMalloc(strlen(class_sig)+1);
2644       strcpy(result, class_sig);
2645     }
2646     *signature_ptr = result;
2647   }
2648   if (generic_ptr != nullptr) {
2649     *generic_ptr = nullptr;
2650     if (!isPrimitive && k->is_instance_klass()) {
2651       Symbol* soo = InstanceKlass::cast(k)->generic_signature();
2652       if (soo != nullptr) {
2653         const char *gen_sig = soo->as_C_string();
2654         if (gen_sig != nullptr) {
2655           char* gen_result;
2656           jvmtiError err = allocate(strlen(gen_sig) + 1,
2657                                     (unsigned char **)&gen_result);
2658           if (err != JVMTI_ERROR_NONE) {
2659             return err;
2660           }
2661           strcpy(gen_result, gen_sig);
2662           *generic_ptr = gen_result;
2663         }
2664       }
2665     }
2666   }
2667   return JVMTI_ERROR_NONE;
2668 } /* end GetClassSignature */
2669 
2670 
2671 // k_mirror - may be primitive, this must be checked
2672 // status_ptr - pre-checked for null
2673 jvmtiError
2674 JvmtiEnv::GetClassStatus(oop k_mirror, jint* status_ptr) {
2675   jint result = 0;
2676   if (java_lang_Class::is_primitive(k_mirror)) {
2677     result |= JVMTI_CLASS_STATUS_PRIMITIVE;
2678   } else {
2679     Klass* k = java_lang_Class::as_Klass(k_mirror);
2680     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2681     result = k->jvmti_class_status();
2682   }
2683   *status_ptr = result;
2684 
2685   return JVMTI_ERROR_NONE;
2686 } /* end GetClassStatus */
2687 
2688 
2689 // k_mirror - may be primitive, this must be checked
2690 // source_name_ptr - pre-checked for null
2691 jvmtiError
2692 JvmtiEnv::GetSourceFileName(oop k_mirror, char** source_name_ptr) {
2693   if (java_lang_Class::is_primitive(k_mirror)) {
2694      return JVMTI_ERROR_ABSENT_INFORMATION;
2695   }
2696   Klass* k_klass = java_lang_Class::as_Klass(k_mirror);
2697   NULL_CHECK(k_klass, JVMTI_ERROR_INVALID_CLASS);
2698 
2699   if (!k_klass->is_instance_klass()) {
2700     return JVMTI_ERROR_ABSENT_INFORMATION;
2701   }
2702 
2703   Symbol* sfnOop = InstanceKlass::cast(k_klass)->source_file_name();
2704   NULL_CHECK(sfnOop, JVMTI_ERROR_ABSENT_INFORMATION);
2705   {
2706     JavaThread* current_thread  = JavaThread::current();
2707     ResourceMark rm(current_thread);
2708     const char* sfncp = (const char*) sfnOop->as_C_string();
2709     *source_name_ptr = (char *) jvmtiMalloc(strlen(sfncp)+1);
2710     strcpy(*source_name_ptr, sfncp);
2711   }
2712 
2713   return JVMTI_ERROR_NONE;
2714 } /* end GetSourceFileName */
2715 
2716 
2717 // k_mirror - may be primitive, this must be checked
2718 // modifiers_ptr - pre-checked for null
2719 jvmtiError
2720 JvmtiEnv::GetClassModifiers(oop k_mirror, jint* modifiers_ptr) {
2721   JavaThread* current_thread  = JavaThread::current();
2722   jint result = 0;
2723   if (!java_lang_Class::is_primitive(k_mirror)) {
2724     Klass* k = java_lang_Class::as_Klass(k_mirror);
2725     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2726     result = k->modifier_flags();
2727 
2728     // Reset the deleted  ACC_SUPER bit (deleted in compute_modifier_flags()).
2729     if (k->is_super()) {
2730       result |= JVM_ACC_SUPER;
2731     }
2732   } else {
2733     result = (JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC);
2734   }
2735   *modifiers_ptr = result;
2736 
2737   return JVMTI_ERROR_NONE;
2738 } /* end GetClassModifiers */
2739 
2740 
2741 // k_mirror - may be primitive, this must be checked
2742 // method_count_ptr - pre-checked for null
2743 // methods_ptr - pre-checked for null
2744 jvmtiError
2745 JvmtiEnv::GetClassMethods(oop k_mirror, jint* method_count_ptr, jmethodID** methods_ptr) {
2746   JavaThread* current_thread  = JavaThread::current();
2747   HandleMark hm(current_thread);
2748 
2749   if (java_lang_Class::is_primitive(k_mirror)) {
2750     *method_count_ptr = 0;
2751     *methods_ptr = (jmethodID*) jvmtiMalloc(0 * sizeof(jmethodID));
2752     return JVMTI_ERROR_NONE;
2753   }
2754   Klass* k = java_lang_Class::as_Klass(k_mirror);
2755   NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2756 
2757   // Return CLASS_NOT_PREPARED error as per JVMTI spec.
2758   if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) )) {
2759     return JVMTI_ERROR_CLASS_NOT_PREPARED;
2760   }
2761 
2762   if (!k->is_instance_klass()) {
2763     *method_count_ptr = 0;
2764     *methods_ptr = (jmethodID*) jvmtiMalloc(0 * sizeof(jmethodID));
2765     return JVMTI_ERROR_NONE;
2766   }
2767   InstanceKlass* ik = InstanceKlass::cast(k);
2768   // Allocate the result and fill it in
2769   int result_length = ik->methods()->length();
2770   jmethodID* result_list = (jmethodID*)jvmtiMalloc(result_length * sizeof(jmethodID));
2771   int index;
2772   bool jmethodids_found = true;
2773   int skipped = 0;  // skip overpass methods
2774 
2775   for (index = 0; index < result_length; index++) {
2776     Method* m = ik->methods()->at(index);
2777     // Depending on can_maintain_original_method_order capability use the original
2778     // method ordering indices stored in the class, so we can emit jmethodIDs in
2779     // the order they appeared in the class file or just copy in current order.
2780     int result_index = JvmtiExport::can_maintain_original_method_order() ? ik->method_ordering()->at(index) : index;
2781     assert(result_index >= 0 && result_index < result_length, "invalid original method index");
2782     if (m->is_overpass()) {
2783       result_list[result_index] = nullptr;
2784       skipped++;
2785       continue;
2786     }
2787     jmethodID id;
2788     if (jmethodids_found) {
2789       id = m->find_jmethod_id_or_null();
2790       if (id == nullptr) {
2791         // If we find an uninitialized value, make sure there is
2792         // enough space for all the uninitialized values we might
2793         // find.
2794         ik->ensure_space_for_methodids(index);
2795         jmethodids_found = false;
2796         id = m->jmethod_id();
2797       }
2798     } else {
2799       id = m->jmethod_id();
2800     }
2801     result_list[result_index] = id;
2802   }
2803 
2804   // Fill in return value.
2805   if (skipped > 0) {
2806     // copy results skipping null methodIDs
2807     *methods_ptr = (jmethodID*)jvmtiMalloc((result_length - skipped) * sizeof(jmethodID));
2808     *method_count_ptr = result_length - skipped;
2809     for (index = 0, skipped = 0; index < result_length; index++) {
2810       if (result_list[index] == nullptr) {
2811         skipped++;
2812       } else {
2813         (*methods_ptr)[index - skipped] = result_list[index];
2814       }
2815     }
2816     deallocate((unsigned char *)result_list);
2817   } else {
2818     *method_count_ptr = result_length;
2819     *methods_ptr = result_list;
2820   }
2821 
2822   return JVMTI_ERROR_NONE;
2823 } /* end GetClassMethods */
2824 
2825 
2826 // k_mirror - may be primitive, this must be checked
2827 // field_count_ptr - pre-checked for null
2828 // fields_ptr - pre-checked for null
2829 jvmtiError
2830 JvmtiEnv::GetClassFields(oop k_mirror, jint* field_count_ptr, jfieldID** fields_ptr) {
2831   if (java_lang_Class::is_primitive(k_mirror)) {
2832     *field_count_ptr = 0;
2833     *fields_ptr = (jfieldID*) jvmtiMalloc(0 * sizeof(jfieldID));
2834     return JVMTI_ERROR_NONE;
2835   }
2836   JavaThread* current_thread = JavaThread::current();
2837   HandleMark hm(current_thread);
2838   Klass* k = java_lang_Class::as_Klass(k_mirror);
2839   NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2840 
2841   // Return CLASS_NOT_PREPARED error as per JVMTI spec.
2842   if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) )) {
2843     return JVMTI_ERROR_CLASS_NOT_PREPARED;
2844   }
2845 
2846   if (!k->is_instance_klass()) {
2847     *field_count_ptr = 0;
2848     *fields_ptr = (jfieldID*) jvmtiMalloc(0 * sizeof(jfieldID));
2849     return JVMTI_ERROR_NONE;
2850   }
2851 
2852   InstanceKlass* ik = InstanceKlass::cast(k);
2853 
2854   FilteredJavaFieldStream flds(ik);
2855 
2856   int result_count = flds.field_count();
2857 
2858   // Allocate the result and fill it in.
2859   jfieldID* result_list = (jfieldID*)jvmtiMalloc(result_count * sizeof(jfieldID));
2860   for (int i = 0; i < result_count; i++, flds.next()) {
2861     result_list[i] = jfieldIDWorkaround::to_jfieldID(ik, flds.offset(),
2862                                                      flds.access_flags().is_static());
2863   }
2864   assert(flds.done(), "just checking");
2865 
2866   // Fill in the results
2867   *field_count_ptr = result_count;
2868   *fields_ptr = result_list;
2869 
2870   return JVMTI_ERROR_NONE;
2871 } /* end GetClassFields */
2872 
2873 
2874 // k_mirror - may be primitive, this must be checked
2875 // interface_count_ptr - pre-checked for null
2876 // interfaces_ptr - pre-checked for null
2877 jvmtiError
2878 JvmtiEnv::GetImplementedInterfaces(oop k_mirror, jint* interface_count_ptr, jclass** interfaces_ptr) {
2879   {
2880     if (java_lang_Class::is_primitive(k_mirror)) {
2881       *interface_count_ptr = 0;
2882       *interfaces_ptr = (jclass*) jvmtiMalloc(0 * sizeof(jclass));
2883       return JVMTI_ERROR_NONE;
2884     }
2885     JavaThread* current_thread = JavaThread::current();
2886     HandleMark hm(current_thread);
2887     Klass* k = java_lang_Class::as_Klass(k_mirror);
2888     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
2889 
2890     // Return CLASS_NOT_PREPARED error as per JVMTI spec.
2891     if (!(k->jvmti_class_status() & (JVMTI_CLASS_STATUS_PREPARED|JVMTI_CLASS_STATUS_ARRAY) ))
2892       return JVMTI_ERROR_CLASS_NOT_PREPARED;
2893 
2894     if (!k->is_instance_klass()) {
2895       *interface_count_ptr = 0;
2896       *interfaces_ptr = (jclass*) jvmtiMalloc(0 * sizeof(jclass));
2897       return JVMTI_ERROR_NONE;
2898     }
2899 
2900     Array<InstanceKlass*>* interface_list = InstanceKlass::cast(k)->local_interfaces();
2901     const int result_length = (interface_list == nullptr ? 0 : interface_list->length());
2902     jclass* result_list = (jclass*) jvmtiMalloc(result_length * sizeof(jclass));
2903     for (int i_index = 0; i_index < result_length; i_index += 1) {
2904       InstanceKlass* klass_at = interface_list->at(i_index);
2905       assert(klass_at->is_klass(), "interfaces must be Klass*s");
2906       assert(klass_at->is_interface(), "interfaces must be interfaces");
2907       oop mirror_at = klass_at->java_mirror();
2908       Handle handle_at = Handle(current_thread, mirror_at);
2909       result_list[i_index] = (jclass) jni_reference(handle_at);
2910     }
2911     *interface_count_ptr = result_length;
2912     *interfaces_ptr = result_list;
2913   }
2914 
2915   return JVMTI_ERROR_NONE;
2916 } /* end GetImplementedInterfaces */
2917 
2918 
2919 // k_mirror - may be primitive, this must be checked
2920 // minor_version_ptr - pre-checked for null
2921 // major_version_ptr - pre-checked for null
2922 jvmtiError
2923 JvmtiEnv::GetClassVersionNumbers(oop k_mirror, jint* minor_version_ptr, jint* major_version_ptr) {
2924   if (java_lang_Class::is_primitive(k_mirror)) {
2925     return JVMTI_ERROR_ABSENT_INFORMATION;
2926   }
2927   Klass* klass = java_lang_Class::as_Klass(k_mirror);
2928 
2929   jint status = klass->jvmti_class_status();
2930   if (status & (JVMTI_CLASS_STATUS_ERROR)) {
2931     return JVMTI_ERROR_INVALID_CLASS;
2932   }
2933   if (status & (JVMTI_CLASS_STATUS_ARRAY)) {
2934     return JVMTI_ERROR_ABSENT_INFORMATION;
2935   }
2936 
2937   InstanceKlass* ik = InstanceKlass::cast(klass);
2938   *minor_version_ptr = ik->minor_version();
2939   *major_version_ptr = ik->major_version();
2940 
2941   return JVMTI_ERROR_NONE;
2942 } /* end GetClassVersionNumbers */
2943 
2944 
2945 // k_mirror - may be primitive, this must be checked
2946 // constant_pool_count_ptr - pre-checked for null
2947 // constant_pool_byte_count_ptr - pre-checked for null
2948 // constant_pool_bytes_ptr - pre-checked for null
2949 jvmtiError
2950 JvmtiEnv::GetConstantPool(oop k_mirror, jint* constant_pool_count_ptr, jint* constant_pool_byte_count_ptr, unsigned char** constant_pool_bytes_ptr) {
2951   if (java_lang_Class::is_primitive(k_mirror)) {
2952     return JVMTI_ERROR_ABSENT_INFORMATION;
2953   }
2954 
2955   Klass* klass = java_lang_Class::as_Klass(k_mirror);
2956   Thread *thread = Thread::current();
2957   ResourceMark rm(thread);
2958 
2959   jint status = klass->jvmti_class_status();
2960   if (status & (JVMTI_CLASS_STATUS_ERROR)) {
2961     return JVMTI_ERROR_INVALID_CLASS;
2962   }
2963   if (status & (JVMTI_CLASS_STATUS_ARRAY)) {
2964     return JVMTI_ERROR_ABSENT_INFORMATION;
2965   }
2966 
2967   InstanceKlass* ik = InstanceKlass::cast(klass);
2968   JvmtiConstantPoolReconstituter reconstituter(ik);
2969   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
2970     return reconstituter.get_error();
2971   }
2972 
2973   unsigned char *cpool_bytes;
2974   int cpool_size = reconstituter.cpool_size();
2975   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
2976     return reconstituter.get_error();
2977   }
2978   jvmtiError res = allocate(cpool_size, &cpool_bytes);
2979   if (res != JVMTI_ERROR_NONE) {
2980     return res;
2981   }
2982   reconstituter.copy_cpool_bytes(cpool_bytes);
2983   if (reconstituter.get_error() != JVMTI_ERROR_NONE) {
2984     return reconstituter.get_error();
2985   }
2986 
2987   constantPoolHandle  constants(thread, ik->constants());
2988   *constant_pool_count_ptr      = constants->length();
2989   *constant_pool_byte_count_ptr = cpool_size;
2990   *constant_pool_bytes_ptr      = cpool_bytes;
2991 
2992   return JVMTI_ERROR_NONE;
2993 } /* end GetConstantPool */
2994 
2995 
2996 // k_mirror - may be primitive, this must be checked
2997 // is_interface_ptr - pre-checked for null
2998 jvmtiError
2999 JvmtiEnv::IsInterface(oop k_mirror, jboolean* is_interface_ptr) {
3000   {
3001     bool result = false;
3002     if (!java_lang_Class::is_primitive(k_mirror)) {
3003       Klass* k = java_lang_Class::as_Klass(k_mirror);
3004       if (k != nullptr && k->is_interface()) {
3005         result = true;
3006       }
3007     }
3008     *is_interface_ptr = result;
3009   }
3010 
3011   return JVMTI_ERROR_NONE;
3012 } /* end IsInterface */
3013 
3014 
3015 // k_mirror - may be primitive, this must be checked
3016 // is_array_class_ptr - pre-checked for null
3017 jvmtiError
3018 JvmtiEnv::IsArrayClass(oop k_mirror, jboolean* is_array_class_ptr) {
3019   {
3020     bool result = false;
3021     if (!java_lang_Class::is_primitive(k_mirror)) {
3022       Klass* k = java_lang_Class::as_Klass(k_mirror);
3023       if (k != nullptr && k->is_array_klass()) {
3024         result = true;
3025       }
3026     }
3027     *is_array_class_ptr = result;
3028   }
3029 
3030   return JVMTI_ERROR_NONE;
3031 } /* end IsArrayClass */
3032 
3033 
3034 // k_mirror - may be primitive, this must be checked
3035 // classloader_ptr - pre-checked for null
3036 jvmtiError
3037 JvmtiEnv::GetClassLoader(oop k_mirror, jobject* classloader_ptr) {
3038   {
3039     if (java_lang_Class::is_primitive(k_mirror)) {
3040       *classloader_ptr = (jclass) jni_reference(Handle());
3041       return JVMTI_ERROR_NONE;
3042     }
3043     JavaThread* current_thread = JavaThread::current();
3044     HandleMark hm(current_thread);
3045     Klass* k = java_lang_Class::as_Klass(k_mirror);
3046     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3047 
3048     oop result_oop = k->class_loader();
3049     if (result_oop == nullptr) {
3050       *classloader_ptr = (jclass) jni_reference(Handle());
3051       return JVMTI_ERROR_NONE;
3052     }
3053     Handle result_handle = Handle(current_thread, result_oop);
3054     jclass result_jnihandle = (jclass) jni_reference(result_handle);
3055     *classloader_ptr = result_jnihandle;
3056   }
3057   return JVMTI_ERROR_NONE;
3058 } /* end GetClassLoader */
3059 
3060 
3061 // k_mirror - may be primitive, this must be checked
3062 // source_debug_extension_ptr - pre-checked for null
3063 jvmtiError
3064 JvmtiEnv::GetSourceDebugExtension(oop k_mirror, char** source_debug_extension_ptr) {
3065   {
3066     if (java_lang_Class::is_primitive(k_mirror)) {
3067       return JVMTI_ERROR_ABSENT_INFORMATION;
3068     }
3069     Klass* k = java_lang_Class::as_Klass(k_mirror);
3070     NULL_CHECK(k, JVMTI_ERROR_INVALID_CLASS);
3071     if (!k->is_instance_klass()) {
3072       return JVMTI_ERROR_ABSENT_INFORMATION;
3073     }
3074     const char* sde = InstanceKlass::cast(k)->source_debug_extension();
3075     NULL_CHECK(sde, JVMTI_ERROR_ABSENT_INFORMATION);
3076 
3077     {
3078       *source_debug_extension_ptr = (char *) jvmtiMalloc(strlen(sde)+1);
3079       strcpy(*source_debug_extension_ptr, sde);
3080     }
3081   }
3082 
3083   return JVMTI_ERROR_NONE;
3084 } /* end GetSourceDebugExtension */
3085 
3086   //
3087   // Object functions
3088   //
3089 
3090 // hash_code_ptr - pre-checked for null
3091 jvmtiError
3092 JvmtiEnv::GetObjectHashCode(jobject object, jint* hash_code_ptr) {
3093   oop mirror = JNIHandles::resolve_external_guard(object);
3094   NULL_CHECK(mirror, JVMTI_ERROR_INVALID_OBJECT);
3095   NULL_CHECK(hash_code_ptr, JVMTI_ERROR_NULL_POINTER);
3096 
3097   {
3098     jint result = (jint) mirror->identity_hash();
3099     *hash_code_ptr = result;
3100   }
3101   return JVMTI_ERROR_NONE;
3102 } /* end GetObjectHashCode */
3103 
3104 
3105 // info_ptr - pre-checked for null
3106 jvmtiError
3107 JvmtiEnv::GetObjectMonitorUsage(jobject object, jvmtiMonitorUsage* info_ptr) {
3108   // This needs to be performed at a safepoint to gather stable data
3109   // because monitor owner / waiters might not be suspended.
3110   VM_GetObjectMonitorUsage op(this, JavaThread::current(), object, info_ptr);
3111   VMThread::execute(&op);
3112   return op.result();
3113 } /* end GetObjectMonitorUsage */
3114 
3115 
3116   //
3117   // Field functions
3118   //
3119 
3120 // name_ptr - null is a valid value, must be checked
3121 // signature_ptr - null is a valid value, must be checked
3122 // generic_ptr - null is a valid value, must be checked
3123 jvmtiError
3124 JvmtiEnv::GetFieldName(fieldDescriptor* fdesc_ptr, char** name_ptr, char** signature_ptr, char** generic_ptr) {
3125   JavaThread* current_thread  = JavaThread::current();
3126   ResourceMark rm(current_thread);
3127   if (name_ptr == nullptr) {
3128     // just don't return the name
3129   } else {
3130     const char* fieldName = fdesc_ptr->name()->as_C_string();
3131     *name_ptr =  (char*) jvmtiMalloc(strlen(fieldName) + 1);
3132     if (*name_ptr == nullptr)
3133       return JVMTI_ERROR_OUT_OF_MEMORY;
3134     strcpy(*name_ptr, fieldName);
3135   }
3136   if (signature_ptr== nullptr) {
3137     // just don't return the signature
3138   } else {
3139     const char* fieldSignature = fdesc_ptr->signature()->as_C_string();
3140     *signature_ptr = (char*) jvmtiMalloc(strlen(fieldSignature) + 1);
3141     if (*signature_ptr == nullptr)
3142       return JVMTI_ERROR_OUT_OF_MEMORY;
3143     strcpy(*signature_ptr, fieldSignature);
3144   }
3145   if (generic_ptr != nullptr) {
3146     *generic_ptr = nullptr;
3147     Symbol* soop = fdesc_ptr->generic_signature();
3148     if (soop != nullptr) {
3149       const char* gen_sig = soop->as_C_string();
3150       if (gen_sig != nullptr) {
3151         jvmtiError err = allocate(strlen(gen_sig) + 1, (unsigned char **)generic_ptr);
3152         if (err != JVMTI_ERROR_NONE) {
3153           return err;
3154         }
3155         strcpy(*generic_ptr, gen_sig);
3156       }
3157     }
3158   }
3159   return JVMTI_ERROR_NONE;
3160 } /* end GetFieldName */
3161 
3162 
3163 // declaring_class_ptr - pre-checked for null
3164 jvmtiError
3165 JvmtiEnv::GetFieldDeclaringClass(fieldDescriptor* fdesc_ptr, jclass* declaring_class_ptr) {
3166   // As for the GetFieldDeclaringClass method, the XSL generated C++ code that calls it has
3167   // a jclass of the relevant class or a subclass of it, which is fine in terms of ensuring
3168   // the holder is kept alive.
3169   *declaring_class_ptr = get_jni_class_non_null(fdesc_ptr->field_holder());
3170   return JVMTI_ERROR_NONE;
3171 } /* end GetFieldDeclaringClass */
3172 
3173 
3174 // modifiers_ptr - pre-checked for null
3175 jvmtiError
3176 JvmtiEnv::GetFieldModifiers(fieldDescriptor* fdesc_ptr, jint* modifiers_ptr) {
3177 
3178   AccessFlags resultFlags = fdesc_ptr->access_flags();
3179   jint result = resultFlags.as_field_flags();
3180   *modifiers_ptr = result;
3181 
3182   return JVMTI_ERROR_NONE;
3183 } /* end GetFieldModifiers */
3184 
3185 
3186 // is_synthetic_ptr - pre-checked for null
3187 jvmtiError
3188 JvmtiEnv::IsFieldSynthetic(fieldDescriptor* fdesc_ptr, jboolean* is_synthetic_ptr) {
3189   *is_synthetic_ptr = fdesc_ptr->is_synthetic();
3190   return JVMTI_ERROR_NONE;
3191 } /* end IsFieldSynthetic */
3192 
3193 
3194   //
3195   // Method functions
3196   //
3197 
3198 // method - pre-checked for validity, but may be null meaning obsolete method
3199 // name_ptr - null is a valid value, must be checked
3200 // signature_ptr - null is a valid value, must be checked
3201 // generic_ptr - null is a valid value, must be checked
3202 jvmtiError
3203 JvmtiEnv::GetMethodName(Method* method, char** name_ptr, char** signature_ptr, char** generic_ptr) {
3204   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3205   JavaThread* current_thread  = JavaThread::current();
3206 
3207   ResourceMark rm(current_thread); // get the utf8 name and signature
3208   if (name_ptr == nullptr) {
3209     // just don't return the name
3210   } else {
3211     const char* utf8_name = (const char *) method->name()->as_utf8();
3212     *name_ptr = (char *) jvmtiMalloc(strlen(utf8_name)+1);
3213     strcpy(*name_ptr, utf8_name);
3214   }
3215   if (signature_ptr == nullptr) {
3216     // just don't return the signature
3217   } else {
3218     const char* utf8_signature = (const char *) method->signature()->as_utf8();
3219     *signature_ptr = (char *) jvmtiMalloc(strlen(utf8_signature) + 1);
3220     strcpy(*signature_ptr, utf8_signature);
3221   }
3222 
3223   if (generic_ptr != nullptr) {
3224     *generic_ptr = nullptr;
3225     Symbol* soop = method->generic_signature();
3226     if (soop != nullptr) {
3227       const char* gen_sig = soop->as_C_string();
3228       if (gen_sig != nullptr) {
3229         jvmtiError err = allocate(strlen(gen_sig) + 1, (unsigned char **)generic_ptr);
3230         if (err != JVMTI_ERROR_NONE) {
3231           return err;
3232         }
3233         strcpy(*generic_ptr, gen_sig);
3234       }
3235     }
3236   }
3237   return JVMTI_ERROR_NONE;
3238 } /* end GetMethodName */
3239 
3240 
3241 // method - pre-checked for validity, but may be null meaning obsolete method
3242 // declaring_class_ptr - pre-checked for null
3243 jvmtiError
3244 JvmtiEnv::GetMethodDeclaringClass(Method* method, jclass* declaring_class_ptr) {
3245   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3246   Klass* k = method->method_holder();
3247   Handle holder(Thread::current(), k->klass_holder()); // keep the klass alive
3248   (*declaring_class_ptr) = get_jni_class_non_null(k);
3249   return JVMTI_ERROR_NONE;
3250 } /* end GetMethodDeclaringClass */
3251 
3252 
3253 // method - pre-checked for validity, but may be null meaning obsolete method
3254 // modifiers_ptr - pre-checked for null
3255 jvmtiError
3256 JvmtiEnv::GetMethodModifiers(Method* method, jint* modifiers_ptr) {
3257   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3258   (*modifiers_ptr) = method->access_flags().as_method_flags();
3259   return JVMTI_ERROR_NONE;
3260 } /* end GetMethodModifiers */
3261 
3262 
3263 // method - pre-checked for validity, but may be null meaning obsolete method
3264 // max_ptr - pre-checked for null
3265 jvmtiError
3266 JvmtiEnv::GetMaxLocals(Method* method, jint* max_ptr) {
3267   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3268   // get max stack
3269   (*max_ptr) = method->max_locals();
3270   return JVMTI_ERROR_NONE;
3271 } /* end GetMaxLocals */
3272 
3273 
3274 // method - pre-checked for validity, but may be null meaning obsolete method
3275 // size_ptr - pre-checked for null
3276 jvmtiError
3277 JvmtiEnv::GetArgumentsSize(Method* method, jint* size_ptr) {
3278   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3279   // get size of arguments
3280 
3281   (*size_ptr) = method->size_of_parameters();
3282   return JVMTI_ERROR_NONE;
3283 } /* end GetArgumentsSize */
3284 
3285 
3286 // method - pre-checked for validity, but may be null meaning obsolete method
3287 // entry_count_ptr - pre-checked for null
3288 // table_ptr - pre-checked for null
3289 jvmtiError
3290 JvmtiEnv::GetLineNumberTable(Method* method, jint* entry_count_ptr, jvmtiLineNumberEntry** table_ptr) {
3291   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3292   if (!method->has_linenumber_table()) {
3293     return (JVMTI_ERROR_ABSENT_INFORMATION);
3294   }
3295 
3296   // The line number table is compressed so we don't know how big it is until decompressed.
3297   // Decompression is really fast so we just do it twice.
3298 
3299   // Compute size of table
3300   jint num_entries = 0;
3301   CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
3302   while (stream.read_pair()) {
3303     num_entries++;
3304   }
3305   jvmtiLineNumberEntry *jvmti_table =
3306             (jvmtiLineNumberEntry *)jvmtiMalloc(num_entries * (sizeof(jvmtiLineNumberEntry)));
3307 
3308   // Fill jvmti table
3309   if (num_entries > 0) {
3310     int index = 0;
3311     CompressedLineNumberReadStream stream(method->compressed_linenumber_table());
3312     while (stream.read_pair()) {
3313       jvmti_table[index].start_location = (jlocation) stream.bci();
3314       jvmti_table[index].line_number = (jint) stream.line();
3315       index++;
3316     }
3317     assert(index == num_entries, "sanity check");
3318   }
3319 
3320   // Set up results
3321   (*entry_count_ptr) = num_entries;
3322   (*table_ptr) = jvmti_table;
3323 
3324   return JVMTI_ERROR_NONE;
3325 } /* end GetLineNumberTable */
3326 
3327 
3328 // method - pre-checked for validity, but may be null meaning obsolete method
3329 // start_location_ptr - pre-checked for null
3330 // end_location_ptr - pre-checked for null
3331 jvmtiError
3332 JvmtiEnv::GetMethodLocation(Method* method, jlocation* start_location_ptr, jlocation* end_location_ptr) {
3333 
3334   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3335   // get start and end location
3336   (*end_location_ptr) = (jlocation) (method->code_size() - 1);
3337   if (method->code_size() == 0) {
3338     // there is no code so there is no start location
3339     (*start_location_ptr) = (jlocation)(-1);
3340   } else {
3341     (*start_location_ptr) = (jlocation)(0);
3342   }
3343 
3344   return JVMTI_ERROR_NONE;
3345 } /* end GetMethodLocation */
3346 
3347 
3348 // method - pre-checked for validity, but may be null meaning obsolete method
3349 // entry_count_ptr - pre-checked for null
3350 // table_ptr - pre-checked for null
3351 jvmtiError
3352 JvmtiEnv::GetLocalVariableTable(Method* method, jint* entry_count_ptr, jvmtiLocalVariableEntry** table_ptr) {
3353 
3354   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3355   JavaThread* current_thread  = JavaThread::current();
3356 
3357   // does the klass have any local variable information?
3358   InstanceKlass* ik = method->method_holder();
3359   if (!ik->has_localvariable_table()) {
3360     return (JVMTI_ERROR_ABSENT_INFORMATION);
3361   }
3362 
3363   ConstantPool* constants = method->constants();
3364   NULL_CHECK(constants, JVMTI_ERROR_ABSENT_INFORMATION);
3365 
3366   // in the vm localvariable table representation, 6 consecutive elements in the table
3367   // represent a 6-tuple of shorts
3368   // [start_pc, length, name_index, descriptor_index, signature_index, index]
3369   jint num_entries = method->localvariable_table_length();
3370   jvmtiLocalVariableEntry *jvmti_table = (jvmtiLocalVariableEntry *)
3371                 jvmtiMalloc(num_entries * (sizeof(jvmtiLocalVariableEntry)));
3372 
3373   if (num_entries > 0) {
3374     LocalVariableTableElement* table = method->localvariable_table_start();
3375     for (int i = 0; i < num_entries; i++) {
3376       // get the 5 tuple information from the vm table
3377       jlocation start_location = (jlocation) table[i].start_bci;
3378       jint length = (jint) table[i].length;
3379       int name_index = (int) table[i].name_cp_index;
3380       int signature_index = (int) table[i].descriptor_cp_index;
3381       int generic_signature_index = (int) table[i].signature_cp_index;
3382       jint slot = (jint) table[i].slot;
3383 
3384       // get utf8 name and signature
3385       char *name_buf = nullptr;
3386       char *sig_buf = nullptr;
3387       char *gen_sig_buf = nullptr;
3388       {
3389         ResourceMark rm(current_thread);
3390 
3391         const char *utf8_name = (const char *) constants->symbol_at(name_index)->as_utf8();
3392         name_buf = (char *) jvmtiMalloc(strlen(utf8_name)+1);
3393         strcpy(name_buf, utf8_name);
3394 
3395         const char *utf8_signature = (const char *) constants->symbol_at(signature_index)->as_utf8();
3396         sig_buf = (char *) jvmtiMalloc(strlen(utf8_signature)+1);
3397         strcpy(sig_buf, utf8_signature);
3398 
3399         if (generic_signature_index > 0) {
3400           const char *utf8_gen_sign = (const char *)
3401                                        constants->symbol_at(generic_signature_index)->as_utf8();
3402           gen_sig_buf = (char *) jvmtiMalloc(strlen(utf8_gen_sign)+1);
3403           strcpy(gen_sig_buf, utf8_gen_sign);
3404         }
3405       }
3406 
3407       // fill in the jvmti local variable table
3408       jvmti_table[i].start_location = start_location;
3409       jvmti_table[i].length = length;
3410       jvmti_table[i].name = name_buf;
3411       jvmti_table[i].signature = sig_buf;
3412       jvmti_table[i].generic_signature = gen_sig_buf;
3413       jvmti_table[i].slot = slot;
3414     }
3415   }
3416 
3417   // set results
3418   (*entry_count_ptr) = num_entries;
3419   (*table_ptr) = jvmti_table;
3420 
3421   return JVMTI_ERROR_NONE;
3422 } /* end GetLocalVariableTable */
3423 
3424 
3425 // method - pre-checked for validity, but may be null meaning obsolete method
3426 // bytecode_count_ptr - pre-checked for null
3427 // bytecodes_ptr - pre-checked for null
3428 jvmtiError
3429 JvmtiEnv::GetBytecodes(Method* method, jint* bytecode_count_ptr, unsigned char** bytecodes_ptr) {
3430   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3431 
3432   methodHandle mh(Thread::current(), method);
3433   jint size = (jint)mh->code_size();
3434   jvmtiError err = allocate(size, bytecodes_ptr);
3435   if (err != JVMTI_ERROR_NONE) {
3436     return err;
3437   }
3438 
3439   (*bytecode_count_ptr) = size;
3440   // get byte codes
3441   JvmtiClassFileReconstituter::copy_bytecodes(mh, *bytecodes_ptr);
3442 
3443   return JVMTI_ERROR_NONE;
3444 } /* end GetBytecodes */
3445 
3446 
3447 // method - pre-checked for validity, but may be null meaning obsolete method
3448 // is_native_ptr - pre-checked for null
3449 jvmtiError
3450 JvmtiEnv::IsMethodNative(Method* method, jboolean* is_native_ptr) {
3451   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3452   (*is_native_ptr) = method->is_native();
3453   return JVMTI_ERROR_NONE;
3454 } /* end IsMethodNative */
3455 
3456 
3457 // method - pre-checked for validity, but may be null meaning obsolete method
3458 // is_synthetic_ptr - pre-checked for null
3459 jvmtiError
3460 JvmtiEnv::IsMethodSynthetic(Method* method, jboolean* is_synthetic_ptr) {
3461   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
3462   (*is_synthetic_ptr) = method->is_synthetic();
3463   return JVMTI_ERROR_NONE;
3464 } /* end IsMethodSynthetic */
3465 
3466 
3467 // method - pre-checked for validity, but may be null meaning obsolete method
3468 // is_obsolete_ptr - pre-checked for null
3469 jvmtiError
3470 JvmtiEnv::IsMethodObsolete(Method* method, jboolean* is_obsolete_ptr) {
3471   if (use_version_1_0_semantics() &&
3472       get_capabilities()->can_redefine_classes == 0) {
3473     // This JvmtiEnv requested version 1.0 semantics and this function
3474     // requires the can_redefine_classes capability in version 1.0 so
3475     // we need to return an error here.
3476     return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
3477   }
3478 
3479   if (method == nullptr || method->is_obsolete()) {
3480     *is_obsolete_ptr = true;
3481   } else {
3482     *is_obsolete_ptr = false;
3483   }
3484   return JVMTI_ERROR_NONE;
3485 } /* end IsMethodObsolete */
3486 
3487   //
3488   // Raw Monitor functions
3489   //
3490 
3491 // name - pre-checked for null
3492 // monitor_ptr - pre-checked for null
3493 jvmtiError
3494 JvmtiEnv::CreateRawMonitor(const char* name, jrawMonitorID* monitor_ptr) {
3495   JvmtiRawMonitor* rmonitor = new (std::nothrow) JvmtiRawMonitor(name);
3496   NULL_CHECK(rmonitor, JVMTI_ERROR_OUT_OF_MEMORY);
3497 
3498   *monitor_ptr = (jrawMonitorID)rmonitor;
3499 
3500   return JVMTI_ERROR_NONE;
3501 } /* end CreateRawMonitor */
3502 
3503 
3504 // rmonitor - pre-checked for validity
3505 jvmtiError
3506 JvmtiEnv::DestroyRawMonitor(JvmtiRawMonitor * rmonitor) {
3507   if (Threads::number_of_threads() == 0) {
3508     // Remove this monitor from pending raw monitors list
3509     // if it has entered in onload or start phase.
3510     JvmtiPendingMonitors::destroy(rmonitor);
3511   } else {
3512     Thread* thread  = Thread::current();
3513     if (rmonitor->owner() == thread) {
3514       // The caller owns this monitor which we are about to destroy.
3515       // We exit the underlying synchronization object so that the
3516       // "delete monitor" call below can work without an assertion
3517       // failure on systems that don't like destroying synchronization
3518       // objects that are locked.
3519       int r;
3520       int recursion = rmonitor->recursions();
3521       for (int i = 0; i <= recursion; i++) {
3522         r = rmonitor->raw_exit(thread);
3523         assert(r == JvmtiRawMonitor::M_OK, "raw_exit should have worked");
3524         if (r != JvmtiRawMonitor::M_OK) {  // robustness
3525           return JVMTI_ERROR_INTERNAL;
3526         }
3527       }
3528     }
3529     if (rmonitor->owner() != nullptr) {
3530       // The caller is trying to destroy a monitor that is locked by
3531       // someone else. While this is not forbidden by the JVMTI
3532       // spec, it will cause an assertion failure on systems that don't
3533       // like destroying synchronization objects that are locked.
3534       // We indicate a problem with the error return (and leak the
3535       // monitor's memory).
3536       return JVMTI_ERROR_NOT_MONITOR_OWNER;
3537     }
3538   }
3539 
3540   delete rmonitor;
3541 
3542   return JVMTI_ERROR_NONE;
3543 } /* end DestroyRawMonitor */
3544 
3545 
3546 // rmonitor - pre-checked for validity
3547 jvmtiError
3548 JvmtiEnv::RawMonitorEnter(JvmtiRawMonitor * rmonitor) {
3549   if (Threads::number_of_threads() == 0) {
3550     // No JavaThreads exist so JvmtiRawMonitor enter cannot be
3551     // used, add this raw monitor to the pending list.
3552     // The pending monitors will be actually entered when
3553     // the VM is setup.
3554     // See transition_pending_raw_monitors in create_vm()
3555     // in thread.cpp.
3556     JvmtiPendingMonitors::enter(rmonitor);
3557   } else {
3558     Thread* thread = Thread::current();
3559     // 8266889: raw_enter changes Java thread state, needs WXWrite
3560     MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
3561     rmonitor->raw_enter(thread);
3562   }
3563   return JVMTI_ERROR_NONE;
3564 } /* end RawMonitorEnter */
3565 
3566 
3567 // rmonitor - pre-checked for validity
3568 jvmtiError
3569 JvmtiEnv::RawMonitorExit(JvmtiRawMonitor * rmonitor) {
3570   jvmtiError err = JVMTI_ERROR_NONE;
3571 
3572   if (Threads::number_of_threads() == 0) {
3573     // No JavaThreads exist so just remove this monitor from the pending list.
3574     // Bool value from exit is false if rmonitor is not in the list.
3575     if (!JvmtiPendingMonitors::exit(rmonitor)) {
3576       err = JVMTI_ERROR_NOT_MONITOR_OWNER;
3577     }
3578   } else {
3579     Thread* thread = Thread::current();
3580     int r = rmonitor->raw_exit(thread);
3581     if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3582       err = JVMTI_ERROR_NOT_MONITOR_OWNER;
3583     }
3584   }
3585   return err;
3586 } /* end RawMonitorExit */
3587 
3588 
3589 // rmonitor - pre-checked for validity
3590 jvmtiError
3591 JvmtiEnv::RawMonitorWait(JvmtiRawMonitor * rmonitor, jlong millis) {
3592   Thread* thread = Thread::current();
3593   // 8266889: raw_wait changes Java thread state, needs WXWrite
3594   MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, thread));
3595   int r = rmonitor->raw_wait(millis, thread);
3596 
3597   switch (r) {
3598   case JvmtiRawMonitor::M_INTERRUPTED:
3599     return JVMTI_ERROR_INTERRUPT;
3600   case JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE:
3601     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3602   default:
3603     return JVMTI_ERROR_NONE;
3604   }
3605 } /* end RawMonitorWait */
3606 
3607 
3608 // rmonitor - pre-checked for validity
3609 jvmtiError
3610 JvmtiEnv::RawMonitorNotify(JvmtiRawMonitor * rmonitor) {
3611   Thread* thread = Thread::current();
3612   int r = rmonitor->raw_notify(thread);
3613 
3614   if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3615     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3616   }
3617   return JVMTI_ERROR_NONE;
3618 } /* end RawMonitorNotify */
3619 
3620 
3621 // rmonitor - pre-checked for validity
3622 jvmtiError
3623 JvmtiEnv::RawMonitorNotifyAll(JvmtiRawMonitor * rmonitor) {
3624   Thread* thread = Thread::current();
3625   int r = rmonitor->raw_notifyAll(thread);
3626 
3627   if (r == JvmtiRawMonitor::M_ILLEGAL_MONITOR_STATE) {
3628     return JVMTI_ERROR_NOT_MONITOR_OWNER;
3629   }
3630   return JVMTI_ERROR_NONE;
3631 } /* end RawMonitorNotifyAll */
3632 
3633 
3634   //
3635   // JNI Function Interception functions
3636   //
3637 
3638 
3639 // function_table - pre-checked for null
3640 jvmtiError
3641 JvmtiEnv::SetJNIFunctionTable(const jniNativeInterface* function_table) {
3642   // Copy jni function table at safepoint.
3643   VM_JNIFunctionTableCopier copier(function_table);
3644   VMThread::execute(&copier);
3645 
3646   return JVMTI_ERROR_NONE;
3647 } /* end SetJNIFunctionTable */
3648 
3649 
3650 // function_table - pre-checked for null
3651 jvmtiError
3652 JvmtiEnv::GetJNIFunctionTable(jniNativeInterface** function_table) {
3653   *function_table=(jniNativeInterface*)jvmtiMalloc(sizeof(jniNativeInterface));
3654   if (*function_table == nullptr)
3655     return JVMTI_ERROR_OUT_OF_MEMORY;
3656   memcpy(*function_table,(JavaThread::current())->get_jni_functions(),sizeof(jniNativeInterface));
3657   return JVMTI_ERROR_NONE;
3658 } /* end GetJNIFunctionTable */
3659 
3660 
3661   //
3662   // Event Management functions
3663   //
3664 
3665 jvmtiError
3666 JvmtiEnv::GenerateEvents(jvmtiEvent event_type) {
3667   // can only generate two event types
3668   if (event_type != JVMTI_EVENT_COMPILED_METHOD_LOAD &&
3669       event_type != JVMTI_EVENT_DYNAMIC_CODE_GENERATED) {
3670     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
3671   }
3672 
3673   // for compiled_method_load events we must check that the environment
3674   // has the can_generate_compiled_method_load_events capability.
3675   if (event_type == JVMTI_EVENT_COMPILED_METHOD_LOAD) {
3676     if (get_capabilities()->can_generate_compiled_method_load_events == 0) {
3677       return JVMTI_ERROR_MUST_POSSESS_CAPABILITY;
3678     }
3679     return JvmtiCodeBlobEvents::generate_compiled_method_load_events(this);
3680   } else {
3681     return JvmtiCodeBlobEvents::generate_dynamic_code_events(this);
3682   }
3683 
3684 } /* end GenerateEvents */
3685 
3686 
3687   //
3688   // Extension Mechanism functions
3689   //
3690 
3691 // extension_count_ptr - pre-checked for null
3692 // extensions - pre-checked for null
3693 jvmtiError
3694 JvmtiEnv::GetExtensionFunctions(jint* extension_count_ptr, jvmtiExtensionFunctionInfo** extensions) {
3695   return JvmtiExtensions::get_functions(this, extension_count_ptr, extensions);
3696 } /* end GetExtensionFunctions */
3697 
3698 
3699 // extension_count_ptr - pre-checked for null
3700 // extensions - pre-checked for null
3701 jvmtiError
3702 JvmtiEnv::GetExtensionEvents(jint* extension_count_ptr, jvmtiExtensionEventInfo** extensions) {
3703   return JvmtiExtensions::get_events(this, extension_count_ptr, extensions);
3704 } /* end GetExtensionEvents */
3705 
3706 
3707 // callback - null is a valid value, must be checked
3708 jvmtiError
3709 JvmtiEnv::SetExtensionEventCallback(jint extension_event_index, jvmtiExtensionEvent callback) {
3710   return JvmtiExtensions::set_event_callback(this, extension_event_index, callback);
3711 } /* end SetExtensionEventCallback */
3712 
3713   //
3714   // Timers functions
3715   //
3716 
3717 // info_ptr - pre-checked for null
3718 jvmtiError
3719 JvmtiEnv::GetCurrentThreadCpuTimerInfo(jvmtiTimerInfo* info_ptr) {
3720   os::current_thread_cpu_time_info(info_ptr);
3721   return JVMTI_ERROR_NONE;
3722 } /* end GetCurrentThreadCpuTimerInfo */
3723 
3724 
3725 // nanos_ptr - pre-checked for null
3726 jvmtiError
3727 JvmtiEnv::GetCurrentThreadCpuTime(jlong* nanos_ptr) {
3728   Thread* thread = Thread::current();
3729 
3730   // Surprisingly the GetCurrentThreadCpuTime is used by non-JavaThread's.
3731   if (thread->is_Java_thread()) {
3732     if (JavaThread::cast(thread)->is_vthread_mounted()) {
3733       // No support for a VirtualThread (yet).
3734       return JVMTI_ERROR_UNSUPPORTED_OPERATION;
3735     }
3736   }
3737   *nanos_ptr = os::current_thread_cpu_time();
3738   return JVMTI_ERROR_NONE;
3739 } /* end GetCurrentThreadCpuTime */
3740 
3741 
3742 // info_ptr - pre-checked for null
3743 jvmtiError
3744 JvmtiEnv::GetThreadCpuTimerInfo(jvmtiTimerInfo* info_ptr) {
3745   os::thread_cpu_time_info(info_ptr);
3746   return JVMTI_ERROR_NONE;
3747 } /* end GetThreadCpuTimerInfo */
3748 
3749 
3750 // nanos_ptr - pre-checked for null
3751 jvmtiError
3752 JvmtiEnv::GetThreadCpuTime(jthread thread, jlong* nanos_ptr) {
3753   JavaThread* current_thread = JavaThread::current();
3754   ThreadsListHandle tlh(current_thread);
3755   JavaThread* java_thread = nullptr;
3756   oop thread_oop = nullptr;
3757 
3758   jvmtiError err = get_threadOop_and_JavaThread(tlh.list(), thread, current_thread, &java_thread, &thread_oop);
3759 
3760   if (thread_oop != nullptr && thread_oop->is_a(vmClasses::BaseVirtualThread_klass())) {
3761     // No support for virtual threads (yet).
3762     return JVMTI_ERROR_UNSUPPORTED_OPERATION;
3763   }
3764   if (err != JVMTI_ERROR_NONE) {
3765     return err;
3766   }
3767   NULL_CHECK(nanos_ptr, JVMTI_ERROR_NULL_POINTER);
3768 
3769   *nanos_ptr = os::thread_cpu_time(java_thread);
3770   return JVMTI_ERROR_NONE;
3771 } /* end GetThreadCpuTime */
3772 
3773 
3774 // info_ptr - pre-checked for null
3775 jvmtiError
3776 JvmtiEnv::GetTimerInfo(jvmtiTimerInfo* info_ptr) {
3777   os::javaTimeNanos_info(info_ptr);
3778   return JVMTI_ERROR_NONE;
3779 } /* end GetTimerInfo */
3780 
3781 
3782 // nanos_ptr - pre-checked for null
3783 jvmtiError
3784 JvmtiEnv::GetTime(jlong* nanos_ptr) {
3785   *nanos_ptr = os::javaTimeNanos();
3786   return JVMTI_ERROR_NONE;
3787 } /* end GetTime */
3788 
3789 
3790 // processor_count_ptr - pre-checked for null
3791 jvmtiError
3792 JvmtiEnv::GetAvailableProcessors(jint* processor_count_ptr) {
3793   *processor_count_ptr = os::active_processor_count();
3794   return JVMTI_ERROR_NONE;
3795 } /* end GetAvailableProcessors */
3796 
3797 jvmtiError
3798 JvmtiEnv::SetHeapSamplingInterval(jint sampling_interval) {
3799   if (sampling_interval < 0) {
3800     return JVMTI_ERROR_ILLEGAL_ARGUMENT;
3801   }
3802   ThreadHeapSampler::set_sampling_interval(sampling_interval);
3803   return JVMTI_ERROR_NONE;
3804 } /* end SetHeapSamplingInterval */
3805 
3806   //
3807   // System Properties functions
3808   //
3809 
3810 // count_ptr - pre-checked for null
3811 // property_ptr - pre-checked for null
3812 jvmtiError
3813 JvmtiEnv::GetSystemProperties(jint* count_ptr, char*** property_ptr) {
3814   jvmtiError err = JVMTI_ERROR_NONE;
3815 
3816   // Get the number of readable properties.
3817   *count_ptr = Arguments::PropertyList_readable_count(Arguments::system_properties());
3818 
3819   // Allocate memory to hold the exact number of readable properties.
3820   err = allocate(*count_ptr * sizeof(char *), (unsigned char **)property_ptr);
3821   if (err != JVMTI_ERROR_NONE) {
3822     return err;
3823   }
3824   int readable_count = 0;
3825   // Loop through the system properties until all the readable properties are found.
3826   for (SystemProperty* p = Arguments::system_properties(); p != nullptr && readable_count < *count_ptr; p = p->next()) {
3827     if (p->readable()) {
3828       const char *key = p->key();
3829       char **tmp_value = *property_ptr+readable_count;
3830       readable_count++;
3831       err = allocate((strlen(key)+1) * sizeof(char), (unsigned char**)tmp_value);
3832       if (err == JVMTI_ERROR_NONE) {
3833         strcpy(*tmp_value, key);
3834       } else {
3835         // clean up previously allocated memory.
3836         for (int j = 0; j < readable_count; j++) {
3837           Deallocate((unsigned char*)*property_ptr+j);
3838         }
3839         Deallocate((unsigned char*)property_ptr);
3840         break;
3841       }
3842     }
3843   }
3844   assert(err != JVMTI_ERROR_NONE || readable_count == *count_ptr, "Bad readable property count");
3845   return err;
3846 } /* end GetSystemProperties */
3847 
3848 
3849 // property - pre-checked for null
3850 // value_ptr - pre-checked for null
3851 jvmtiError
3852 JvmtiEnv::GetSystemProperty(const char* property, char** value_ptr) {
3853   jvmtiError err = JVMTI_ERROR_NONE;
3854   const char *value;
3855 
3856   // Return JVMTI_ERROR_NOT_AVAILABLE if property is not readable or doesn't exist.
3857   value = Arguments::PropertyList_get_readable_value(Arguments::system_properties(), property);
3858   if (value == nullptr) {
3859     err =  JVMTI_ERROR_NOT_AVAILABLE;
3860   } else {
3861     err = allocate((strlen(value)+1) * sizeof(char), (unsigned char **)value_ptr);
3862     if (err == JVMTI_ERROR_NONE) {
3863       strcpy(*value_ptr, value);
3864     }
3865   }
3866   return err;
3867 } /* end GetSystemProperty */
3868 
3869 
3870 // property - pre-checked for null
3871 // value - null is a valid value, must be checked
3872 jvmtiError
3873 JvmtiEnv::SetSystemProperty(const char* property, const char* value_ptr) {
3874   for (SystemProperty* p = Arguments::system_properties(); p != nullptr; p = p->next()) {
3875     if (strcmp(property, p->key()) == 0) {
3876       if (p->writeable()) {
3877         if (p->set_value(value_ptr, AllocFailStrategy::RETURN_NULL)) {
3878           return JVMTI_ERROR_NONE;
3879         } else {
3880           return JVMTI_ERROR_OUT_OF_MEMORY;
3881         }
3882       } else {
3883         // We found a property, but it's not writeable
3884         return JVMTI_ERROR_NOT_AVAILABLE;
3885       }
3886     }
3887   }
3888 
3889   // We cannot find a property of the given name
3890   return JVMTI_ERROR_NOT_AVAILABLE;
3891 } /* end SetSystemProperty */