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