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Editing: v8-isolate.h
// Copyright 2021 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef INCLUDE_V8_ISOLATE_H_ #define INCLUDE_V8_ISOLATE_H_ #include <stddef.h> #include <stdint.h> #include <memory> #include <utility> #include "cppgc/common.h" #include "v8-array-buffer.h" // NOLINT(build/include_directory) #include "v8-callbacks.h" // NOLINT(build/include_directory) #include "v8-data.h" // NOLINT(build/include_directory) #include "v8-debug.h" // NOLINT(build/include_directory) #include "v8-embedder-heap.h" // NOLINT(build/include_directory) #include "v8-function-callback.h" // NOLINT(build/include_directory) #include "v8-internal.h" // NOLINT(build/include_directory) #include "v8-local-handle.h" // NOLINT(build/include_directory) #include "v8-microtask.h" // NOLINT(build/include_directory) #include "v8-persistent-handle.h" // NOLINT(build/include_directory) #include "v8-primitive.h" // NOLINT(build/include_directory) #include "v8-statistics.h" // NOLINT(build/include_directory) #include "v8-unwinder.h" // NOLINT(build/include_directory) #include "v8config.h" // NOLINT(build/include_directory) namespace v8 { class CppHeap; class HeapProfiler; class MicrotaskQueue; class StartupData; class ScriptOrModule; class SharedArrayBuffer; namespace internal { class MicrotaskQueue; class ThreadLocalTop; } // namespace internal namespace metrics { class Recorder; } // namespace metrics /** * A set of constraints that specifies the limits of the runtime's memory use. * You must set the heap size before initializing the VM - the size cannot be * adjusted after the VM is initialized. * * If you are using threads then you should hold the V8::Locker lock while * setting the stack limit and you must set a non-default stack limit separately * for each thread. * * The arguments for set_max_semi_space_size, set_max_old_space_size, * set_max_executable_size, set_code_range_size specify limits in MB. * * The argument for set_max_semi_space_size_in_kb is in KB. */ class V8_EXPORT ResourceConstraints { public: /** * Configures the constraints with reasonable default values based on the * provided heap size limit. The heap size includes both the young and * the old generation. * * \param initial_heap_size_in_bytes The initial heap size or zero. * By default V8 starts with a small heap and dynamically grows it to * match the set of live objects. This may lead to ineffective * garbage collections at startup if the live set is large. * Setting the initial heap size avoids such garbage collections. * Note that this does not affect young generation garbage collections. * * \param maximum_heap_size_in_bytes The hard limit for the heap size. * When the heap size approaches this limit, V8 will perform series of * garbage collections and invoke the NearHeapLimitCallback. If the garbage * collections do not help and the callback does not increase the limit, * then V8 will crash with V8::FatalProcessOutOfMemory. */ void ConfigureDefaultsFromHeapSize(size_t initial_heap_size_in_bytes, size_t maximum_heap_size_in_bytes); /** * Configures the constraints with reasonable default values based on the * capabilities of the current device the VM is running on. * * \param physical_memory The total amount of physical memory on the current * device, in bytes. * \param virtual_memory_limit The amount of virtual memory on the current * device, in bytes, or zero, if there is no limit. */ void ConfigureDefaults(uint64_t physical_memory, uint64_t virtual_memory_limit); /** * The address beyond which the VM's stack may not grow. */ uint32_t* stack_limit() const { return stack_limit_; } void set_stack_limit(uint32_t* value) { stack_limit_ = value; } /** * The amount of virtual memory reserved for generated code. This is relevant * for 64-bit architectures that rely on code range for calls in code. * * When V8_COMPRESS_POINTERS_IN_SHARED_CAGE is defined, there is a shared * process-wide code range that is lazily initialized. This value is used to * configure that shared code range when the first Isolate is * created. Subsequent Isolates ignore this value. */ size_t code_range_size_in_bytes() const { return code_range_size_; } void set_code_range_size_in_bytes(size_t limit) { code_range_size_ = limit; } /** * The maximum size of the old generation. * When the old generation approaches this limit, V8 will perform series of * garbage collections and invoke the NearHeapLimitCallback. * If the garbage collections do not help and the callback does not * increase the limit, then V8 will crash with V8::FatalProcessOutOfMemory. */ size_t max_old_generation_size_in_bytes() const { return max_old_generation_size_; } void set_max_old_generation_size_in_bytes(size_t limit) { max_old_generation_size_ = limit; } /** * The maximum size of the young generation, which consists of two semi-spaces * and a large object space. This affects frequency of Scavenge garbage * collections and should be typically much smaller that the old generation. */ size_t max_young_generation_size_in_bytes() const { return max_young_generation_size_; } void set_max_young_generation_size_in_bytes(size_t limit) { max_young_generation_size_ = limit; } size_t initial_old_generation_size_in_bytes() const { return initial_old_generation_size_; } void set_initial_old_generation_size_in_bytes(size_t initial_size) { initial_old_generation_size_ = initial_size; } size_t initial_young_generation_size_in_bytes() const { return initial_young_generation_size_; } void set_initial_young_generation_size_in_bytes(size_t initial_size) { initial_young_generation_size_ = initial_size; } private: static constexpr size_t kMB = 1048576u; size_t code_range_size_ = 0; size_t max_old_generation_size_ = 0; size_t max_young_generation_size_ = 0; size_t initial_old_generation_size_ = 0; size_t initial_young_generation_size_ = 0; uint32_t* stack_limit_ = nullptr; }; /** * Option flags passed to the SetRAILMode function. * See documentation https://developers.google.com/web/tools/chrome-devtools/ * profile/evaluate-performance/rail */ enum RAILMode : unsigned { // Response performance mode: In this mode very low virtual machine latency // is provided. V8 will try to avoid JavaScript execution interruptions. // Throughput may be throttled. PERFORMANCE_RESPONSE, // Animation performance mode: In this mode low virtual machine latency is // provided. V8 will try to avoid as many JavaScript execution interruptions // as possible. Throughput may be throttled. This is the default mode. PERFORMANCE_ANIMATION, // Idle performance mode: The embedder is idle. V8 can complete deferred work // in this mode. PERFORMANCE_IDLE, // Load performance mode: In this mode high throughput is provided. V8 may // turn off latency optimizations. PERFORMANCE_LOAD }; /** * Memory pressure level for the MemoryPressureNotification. * kNone hints V8 that there is no memory pressure. * kModerate hints V8 to speed up incremental garbage collection at the cost of * of higher latency due to garbage collection pauses. * kCritical hints V8 to free memory as soon as possible. Garbage collection * pauses at this level will be large. */ enum class MemoryPressureLevel { kNone, kModerate, kCritical }; /** * Isolate represents an isolated instance of the V8 engine. V8 isolates have * completely separate states. Objects from one isolate must not be used in * other isolates. The embedder can create multiple isolates and use them in * parallel in multiple threads. An isolate can be entered by at most one * thread at any given time. The Locker/Unlocker API must be used to * synchronize. */ class V8_EXPORT Isolate { public: /** * Initial configuration parameters for a new Isolate. */ struct V8_EXPORT CreateParams { CreateParams(); ~CreateParams(); /** * Allows the host application to provide the address of a function that is * notified each time code is added, moved or removed. */ JitCodeEventHandler code_event_handler = nullptr; /** * ResourceConstraints to use for the new Isolate. */ ResourceConstraints constraints; /** * Explicitly specify a startup snapshot blob. The embedder owns the blob. * The embedder *must* ensure that the snapshot is from a trusted source. */ StartupData* snapshot_blob = nullptr; /** * Enables the host application to provide a mechanism for recording * statistics counters. */ CounterLookupCallback counter_lookup_callback = nullptr; /** * Enables the host application to provide a mechanism for recording * histograms. The CreateHistogram function returns a * histogram which will later be passed to the AddHistogramSample * function. */ CreateHistogramCallback create_histogram_callback = nullptr; AddHistogramSampleCallback add_histogram_sample_callback = nullptr; /** * The ArrayBuffer::Allocator to use for allocating and freeing the backing * store of ArrayBuffers. * * If the shared_ptr version is used, the Isolate instance and every * |BackingStore| allocated using this allocator hold a std::shared_ptr * to the allocator, in order to facilitate lifetime * management for the allocator instance. */ ArrayBuffer::Allocator* array_buffer_allocator = nullptr; std::shared_ptr<ArrayBuffer::Allocator> array_buffer_allocator_shared; /** * Specifies an optional nullptr-terminated array of raw addresses in the * embedder that V8 can match against during serialization and use for * deserialization. This array and its content must stay valid for the * entire lifetime of the isolate. */ const intptr_t* external_references = nullptr; /** * Whether calling Atomics.wait (a function that may block) is allowed in * this isolate. This can also be configured via SetAllowAtomicsWait. */ bool allow_atomics_wait = true; /** * Termination is postponed when there is no active SafeForTerminationScope. */ bool only_terminate_in_safe_scope = false; /** * The following parameters describe the offsets for addressing type info * for wrapped API objects and are used by the fast C API * (for details see v8-fast-api-calls.h). */ int embedder_wrapper_type_index = -1; int embedder_wrapper_object_index = -1; /** * Callbacks to invoke in case of fatal or OOM errors. */ FatalErrorCallback fatal_error_callback = nullptr; OOMErrorCallback oom_error_callback = nullptr; /** * The following parameter is experimental and may change significantly. * This is currently for internal testing. */ Isolate* experimental_attach_to_shared_isolate = nullptr; }; /** * Stack-allocated class which sets the isolate for all operations * executed within a local scope. */ class V8_EXPORT V8_NODISCARD Scope { public: explicit Scope(Isolate* isolate) : isolate_(isolate) { isolate->Enter(); } ~Scope() { isolate_->Exit(); } // Prevent copying of Scope objects. Scope(const Scope&) = delete; Scope& operator=(const Scope&) = delete; private: Isolate* const isolate_; }; /** * Assert that no Javascript code is invoked. */ class V8_EXPORT V8_NODISCARD DisallowJavascriptExecutionScope { public: enum OnFailure { CRASH_ON_FAILURE, THROW_ON_FAILURE, DUMP_ON_FAILURE }; DisallowJavascriptExecutionScope(Isolate* isolate, OnFailure on_failure); ~DisallowJavascriptExecutionScope(); // Prevent copying of Scope objects. DisallowJavascriptExecutionScope(const DisallowJavascriptExecutionScope&) = delete; DisallowJavascriptExecutionScope& operator=( const DisallowJavascriptExecutionScope&) = delete; private: OnFailure on_failure_; Isolate* isolate_; bool was_execution_allowed_assert_; bool was_execution_allowed_throws_; bool was_execution_allowed_dump_; }; /** * Introduce exception to DisallowJavascriptExecutionScope. */ class V8_EXPORT V8_NODISCARD AllowJavascriptExecutionScope { public: explicit AllowJavascriptExecutionScope(Isolate* isolate); ~AllowJavascriptExecutionScope(); // Prevent copying of Scope objects. AllowJavascriptExecutionScope(const AllowJavascriptExecutionScope&) = delete; AllowJavascriptExecutionScope& operator=( const AllowJavascriptExecutionScope&) = delete; private: Isolate* isolate_; bool was_execution_allowed_assert_; bool was_execution_allowed_throws_; bool was_execution_allowed_dump_; }; /** * Do not run microtasks while this scope is active, even if microtasks are * automatically executed otherwise. */ class V8_EXPORT V8_NODISCARD SuppressMicrotaskExecutionScope { public: explicit SuppressMicrotaskExecutionScope( Isolate* isolate, MicrotaskQueue* microtask_queue = nullptr); ~SuppressMicrotaskExecutionScope(); // Prevent copying of Scope objects. SuppressMicrotaskExecutionScope(const SuppressMicrotaskExecutionScope&) = delete; SuppressMicrotaskExecutionScope& operator=( const SuppressMicrotaskExecutionScope&) = delete; private: internal::Isolate* const isolate_; internal::MicrotaskQueue* const microtask_queue_; internal::Address previous_stack_height_; friend class internal::ThreadLocalTop; }; /** * This scope allows terminations inside direct V8 API calls and forbid them * inside any recursive API calls without explicit SafeForTerminationScope. */ class V8_EXPORT V8_NODISCARD SafeForTerminationScope { public: explicit SafeForTerminationScope(v8::Isolate* isolate); ~SafeForTerminationScope(); // Prevent copying of Scope objects. SafeForTerminationScope(const SafeForTerminationScope&) = delete; SafeForTerminationScope& operator=(const SafeForTerminationScope&) = delete; private: internal::Isolate* isolate_; bool prev_value_; }; /** * Types of garbage collections that can be requested via * RequestGarbageCollectionForTesting. */ enum GarbageCollectionType { kFullGarbageCollection, kMinorGarbageCollection }; /** * Features reported via the SetUseCounterCallback callback. Do not change * assigned numbers of existing items; add new features to the end of this * list. */ enum UseCounterFeature { kUseAsm = 0, kBreakIterator = 1, kLegacyConst = 2, kMarkDequeOverflow = 3, kStoreBufferOverflow = 4, kSlotsBufferOverflow = 5, kObjectObserve = 6, kForcedGC = 7, kSloppyMode = 8, kStrictMode = 9, kStrongMode = 10, kRegExpPrototypeStickyGetter = 11, kRegExpPrototypeToString = 12, kRegExpPrototypeUnicodeGetter = 13, kIntlV8Parse = 14, kIntlPattern = 15, kIntlResolved = 16, kPromiseChain = 17, kPromiseAccept = 18, kPromiseDefer = 19, kHtmlCommentInExternalScript = 20, kHtmlComment = 21, kSloppyModeBlockScopedFunctionRedefinition = 22, kForInInitializer = 23, kArrayProtectorDirtied = 24, kArraySpeciesModified = 25, kArrayPrototypeConstructorModified = 26, kArrayInstanceProtoModified = 27, kArrayInstanceConstructorModified = 28, kLegacyFunctionDeclaration = 29, kRegExpPrototypeSourceGetter = 30, // Unused. kRegExpPrototypeOldFlagGetter = 31, // Unused. kDecimalWithLeadingZeroInStrictMode = 32, kLegacyDateParser = 33, kDefineGetterOrSetterWouldThrow = 34, kFunctionConstructorReturnedUndefined = 35, kAssigmentExpressionLHSIsCallInSloppy = 36, kAssigmentExpressionLHSIsCallInStrict = 37, kPromiseConstructorReturnedUndefined = 38, kConstructorNonUndefinedPrimitiveReturn = 39, kLabeledExpressionStatement = 40, kLineOrParagraphSeparatorAsLineTerminator = 41, kIndexAccessor = 42, kErrorCaptureStackTrace = 43, kErrorPrepareStackTrace = 44, kErrorStackTraceLimit = 45, kWebAssemblyInstantiation = 46, kDeoptimizerDisableSpeculation = 47, kArrayPrototypeSortJSArrayModifiedPrototype = 48, kFunctionTokenOffsetTooLongForToString = 49, kWasmSharedMemory = 50, kWasmThreadOpcodes = 51, kAtomicsNotify = 52, // Unused. kAtomicsWake = 53, // Unused. kCollator = 54, kNumberFormat = 55, kDateTimeFormat = 56, kPluralRules = 57, kRelativeTimeFormat = 58, kLocale = 59, kListFormat = 60, kSegmenter = 61, kStringLocaleCompare = 62, kStringToLocaleUpperCase = 63, kStringToLocaleLowerCase = 64, kNumberToLocaleString = 65, kDateToLocaleString = 66, kDateToLocaleDateString = 67, kDateToLocaleTimeString = 68, kAttemptOverrideReadOnlyOnPrototypeSloppy = 69, kAttemptOverrideReadOnlyOnPrototypeStrict = 70, kOptimizedFunctionWithOneShotBytecode = 71, // Unused. kRegExpMatchIsTrueishOnNonJSRegExp = 72, kRegExpMatchIsFalseishOnJSRegExp = 73, kDateGetTimezoneOffset = 74, // Unused. kStringNormalize = 75, kCallSiteAPIGetFunctionSloppyCall = 76, kCallSiteAPIGetThisSloppyCall = 77, kRegExpMatchAllWithNonGlobalRegExp = 78, kRegExpExecCalledOnSlowRegExp = 79, kRegExpReplaceCalledOnSlowRegExp = 80, kDisplayNames = 81, kSharedArrayBufferConstructed = 82, kArrayPrototypeHasElements = 83, kObjectPrototypeHasElements = 84, kNumberFormatStyleUnit = 85, kDateTimeFormatRange = 86, kDateTimeFormatDateTimeStyle = 87, kBreakIteratorTypeWord = 88, kBreakIteratorTypeLine = 89, kInvalidatedArrayBufferDetachingProtector = 90, kInvalidatedArrayConstructorProtector = 91, kInvalidatedArrayIteratorLookupChainProtector = 92, kInvalidatedArraySpeciesLookupChainProtector = 93, kInvalidatedIsConcatSpreadableLookupChainProtector = 94, kInvalidatedMapIteratorLookupChainProtector = 95, kInvalidatedNoElementsProtector = 96, kInvalidatedPromiseHookProtector = 97, kInvalidatedPromiseResolveLookupChainProtector = 98, kInvalidatedPromiseSpeciesLookupChainProtector = 99, kInvalidatedPromiseThenLookupChainProtector = 100, kInvalidatedRegExpSpeciesLookupChainProtector = 101, kInvalidatedSetIteratorLookupChainProtector = 102, kInvalidatedStringIteratorLookupChainProtector = 103, kInvalidatedStringLengthOverflowLookupChainProtector = 104, kInvalidatedTypedArraySpeciesLookupChainProtector = 105, kWasmSimdOpcodes = 106, kVarRedeclaredCatchBinding = 107, kWasmRefTypes = 108, kWasmBulkMemory = 109, // Unused. kWasmMultiValue = 110, kWasmExceptionHandling = 111, kInvalidatedMegaDOMProtector = 112, kFunctionPrototypeArguments = 113, kFunctionPrototypeCaller = 114, // If you add new values here, you'll also need to update Chromium's: // web_feature.mojom, use_counter_callback.cc, and enums.xml. V8 changes to // this list need to be landed first, then changes on the Chromium side. kUseCounterFeatureCount // This enum value must be last. }; enum MessageErrorLevel { kMessageLog = (1 << 0), kMessageDebug = (1 << 1), kMessageInfo = (1 << 2), kMessageError = (1 << 3), kMessageWarning = (1 << 4), kMessageAll = kMessageLog | kMessageDebug | kMessageInfo | kMessageError | kMessageWarning, }; using UseCounterCallback = void (*)(Isolate* isolate, UseCounterFeature feature); /** * Allocates a new isolate but does not initialize it. Does not change the * currently entered isolate. * * Only Isolate::GetData() and Isolate::SetData(), which access the * embedder-controlled parts of the isolate, are allowed to be called on the * uninitialized isolate. To initialize the isolate, call * Isolate::Initialize(). * * When an isolate is no longer used its resources should be freed * by calling Dispose(). Using the delete operator is not allowed. * * V8::Initialize() must have run prior to this. */ static Isolate* Allocate(); /** * Initialize an Isolate previously allocated by Isolate::Allocate(). */ static void Initialize(Isolate* isolate, const CreateParams& params); /** * Creates a new isolate. Does not change the currently entered * isolate. * * When an isolate is no longer used its resources should be freed * by calling Dispose(). Using the delete operator is not allowed. * * V8::Initialize() must have run prior to this. */ static Isolate* New(const CreateParams& params); /** * Returns the entered isolate for the current thread or NULL in * case there is no current isolate. * * This method must not be invoked before V8::Initialize() was invoked. */ static Isolate* GetCurrent(); /** * Returns the entered isolate for the current thread or NULL in * case there is no current isolate. * * No checks are performed by this method. */ static Isolate* TryGetCurrent(); /** * Return true if this isolate is currently active. **/ bool IsCurrent() const; /** * Clears the set of objects held strongly by the heap. This set of * objects are originally built when a WeakRef is created or * successfully dereferenced. * * This is invoked automatically after microtasks are run. See * MicrotasksPolicy for when microtasks are run. * * This needs to be manually invoked only if the embedder is manually running * microtasks via a custom MicrotaskQueue class's PerformCheckpoint. In that * case, it is the embedder's responsibility to make this call at a time which * does not interrupt synchronous ECMAScript code execution. */ void ClearKeptObjects(); /** * Custom callback used by embedders to help V8 determine if it should abort * when it throws and no internal handler is predicted to catch the * exception. If --abort-on-uncaught-exception is used on the command line, * then V8 will abort if either: * - no custom callback is set. * - the custom callback set returns true. * Otherwise, the custom callback will not be called and V8 will not abort. */ using AbortOnUncaughtExceptionCallback = bool (*)(Isolate*); void SetAbortOnUncaughtExceptionCallback( AbortOnUncaughtExceptionCallback callback); /** * This specifies the callback called by the upcoming dynamic * import() language feature to load modules. */ V8_DEPRECATED("Use HostImportModuleDynamicallyCallback") void SetHostImportModuleDynamicallyCallback( HostImportModuleDynamicallyWithImportAssertionsCallback callback); void SetHostImportModuleDynamicallyCallback( HostImportModuleDynamicallyCallback callback); /** * This specifies the callback called by the upcoming import.meta * language feature to retrieve host-defined meta data for a module. */ void SetHostInitializeImportMetaObjectCallback( HostInitializeImportMetaObjectCallback callback); /** * This specifies the callback called by the upcoming ShadowRealm * construction language feature to retrieve host created globals. */ void SetHostCreateShadowRealmContextCallback( HostCreateShadowRealmContextCallback callback); /** * This specifies the callback called when the stack property of Error * is accessed. */ void SetPrepareStackTraceCallback(PrepareStackTraceCallback callback); /** * Optional notification that the system is running low on memory. * V8 uses these notifications to guide heuristics. * It is allowed to call this function from another thread while * the isolate is executing long running JavaScript code. */ void MemoryPressureNotification(MemoryPressureLevel level); /** * Drop non-essential caches. Should only be called from testing code. * The method can potentially block for a long time and does not necessarily * trigger GC. */ void ClearCachesForTesting(); /** * Methods below this point require holding a lock (using Locker) in * a multi-threaded environment. */ /** * Sets this isolate as the entered one for the current thread. * Saves the previously entered one (if any), so that it can be * restored when exiting. Re-entering an isolate is allowed. */ void Enter(); /** * Exits this isolate by restoring the previously entered one in the * current thread. The isolate may still stay the same, if it was * entered more than once. * * Requires: this == Isolate::GetCurrent(). */ void Exit(); /** * Disposes the isolate. The isolate must not be entered by any * thread to be disposable. */ void Dispose(); /** * Dumps activated low-level V8 internal stats. This can be used instead * of performing a full isolate disposal. */ void DumpAndResetStats(); /** * Discards all V8 thread-specific data for the Isolate. Should be used * if a thread is terminating and it has used an Isolate that will outlive * the thread -- all thread-specific data for an Isolate is discarded when * an Isolate is disposed so this call is pointless if an Isolate is about * to be Disposed. */ void DiscardThreadSpecificMetadata(); /** * Associate embedder-specific data with the isolate. |slot| has to be * between 0 and GetNumberOfDataSlots() - 1. */ V8_INLINE void SetData(uint32_t slot, void* data); /** * Retrieve embedder-specific data from the isolate. * Returns NULL if SetData has never been called for the given |slot|. */ V8_INLINE void* GetData(uint32_t slot); /** * Returns the maximum number of available embedder data slots. Valid slots * are in the range of 0 - GetNumberOfDataSlots() - 1. */ V8_INLINE static uint32_t GetNumberOfDataSlots(); /** * Return data that was previously attached to the isolate snapshot via * SnapshotCreator, and removes the reference to it. * Repeated call with the same index returns an empty MaybeLocal. */ template <class T> V8_INLINE MaybeLocal<T> GetDataFromSnapshotOnce(size_t index); /** * Get statistics about the heap memory usage. */ void GetHeapStatistics(HeapStatistics* heap_statistics); /** * Returns the number of spaces in the heap. */ size_t NumberOfHeapSpaces(); /** * Get the memory usage of a space in the heap. * * \param space_statistics The HeapSpaceStatistics object to fill in * statistics. * \param index The index of the space to get statistics from, which ranges * from 0 to NumberOfHeapSpaces() - 1. * \returns true on success. */ bool GetHeapSpaceStatistics(HeapSpaceStatistics* space_statistics, size_t index); /** * Returns the number of types of objects tracked in the heap at GC. */ size_t NumberOfTrackedHeapObjectTypes(); /** * Get statistics about objects in the heap. * * \param object_statistics The HeapObjectStatistics object to fill in * statistics of objects of given type, which were live in the previous GC. * \param type_index The index of the type of object to fill details about, * which ranges from 0 to NumberOfTrackedHeapObjectTypes() - 1. * \returns true on success. */ bool GetHeapObjectStatisticsAtLastGC(HeapObjectStatistics* object_statistics, size_t type_index); /** * Get statistics about code and its metadata in the heap. * * \param object_statistics The HeapCodeStatistics object to fill in * statistics of code, bytecode and their metadata. * \returns true on success. */ bool GetHeapCodeAndMetadataStatistics(HeapCodeStatistics* object_statistics); /** * This API is experimental and may change significantly. * * Enqueues a memory measurement request and invokes the delegate with the * results. * * \param delegate the delegate that defines which contexts to measure and * reports the results. * * \param execution promptness executing the memory measurement. * The kEager value is expected to be used only in tests. */ bool MeasureMemory( std::unique_ptr<MeasureMemoryDelegate> delegate, MeasureMemoryExecution execution = MeasureMemoryExecution::kDefault); /** * Get a call stack sample from the isolate. * \param state Execution state. * \param frames Caller allocated buffer to store stack frames. * \param frames_limit Maximum number of frames to capture. The buffer must * be large enough to hold the number of frames. * \param sample_info The sample info is filled up by the function * provides number of actual captured stack frames and * the current VM state. * \note GetStackSample should only be called when the JS thread is paused or * interrupted. Otherwise the behavior is undefined. */ void GetStackSample(const RegisterState& state, void** frames, size_t frames_limit, SampleInfo* sample_info); /** * Adjusts the amount of registered external memory. Used to give V8 an * indication of the amount of externally allocated memory that is kept alive * by JavaScript objects. V8 uses this to decide when to perform global * garbage collections. Registering externally allocated memory will trigger * global garbage collections more often than it would otherwise in an attempt * to garbage collect the JavaScript objects that keep the externally * allocated memory alive. * * \param change_in_bytes the change in externally allocated memory that is * kept alive by JavaScript objects. * \returns the adjusted value. */ int64_t AdjustAmountOfExternalAllocatedMemory(int64_t change_in_bytes); /** * Returns the number of phantom handles without callbacks that were reset * by the garbage collector since the last call to this function. */ size_t NumberOfPhantomHandleResetsSinceLastCall(); /** * Returns heap profiler for this isolate. Will return NULL until the isolate * is initialized. */ HeapProfiler* GetHeapProfiler(); /** * Tells the VM whether the embedder is idle or not. */ void SetIdle(bool is_idle); /** Returns the ArrayBuffer::Allocator used in this isolate. */ ArrayBuffer::Allocator* GetArrayBufferAllocator(); /** Returns true if this isolate has a current context. */ bool InContext(); /** * Returns the context of the currently running JavaScript, or the context * on the top of the stack if no JavaScript is running. */ Local<Context> GetCurrentContext(); /** * Returns either the last context entered through V8's C++ API, or the * context of the currently running microtask while processing microtasks. * If a context is entered while executing a microtask, that context is * returned. */ Local<Context> GetEnteredOrMicrotaskContext(); /** * Returns the Context that corresponds to the Incumbent realm in HTML spec. * https://html.spec.whatwg.org/multipage/webappapis.html#incumbent */ Local<Context> GetIncumbentContext(); /** * Schedules a v8::Exception::Error with the given message. * See ThrowException for more details. Templatized to provide compile-time * errors in case of too long strings (see v8::String::NewFromUtf8Literal). */ template <int N> Local<Value> ThrowError(const char (&message)[N]) { return ThrowError(String::NewFromUtf8Literal(this, message)); } Local<Value> ThrowError(Local<String> message); /** * Schedules an exception to be thrown when returning to JavaScript. When an * exception has been scheduled it is illegal to invoke any JavaScript * operation; the caller must return immediately and only after the exception * has been handled does it become legal to invoke JavaScript operations. */ Local<Value> ThrowException(Local<Value> exception); using GCCallback = void (*)(Isolate* isolate, GCType type, GCCallbackFlags flags); using GCCallbackWithData = void (*)(Isolate* isolate, GCType type, GCCallbackFlags flags, void* data); /** * Enables the host application to receive a notification before a * garbage collection. Allocations are allowed in the callback function, * but the callback is not re-entrant: if the allocation inside it will * trigger the garbage collection, the callback won't be called again. * It is possible to specify the GCType filter for your callback. But it is * not possible to register the same callback function two times with * different GCType filters. */ void AddGCPrologueCallback(GCCallbackWithData callback, void* data = nullptr, GCType gc_type_filter = kGCTypeAll); void AddGCPrologueCallback(GCCallback callback, GCType gc_type_filter = kGCTypeAll); /** * This function removes callback which was installed by * AddGCPrologueCallback function. */ void RemoveGCPrologueCallback(GCCallbackWithData, void* data = nullptr); void RemoveGCPrologueCallback(GCCallback callback); /** * Sets the embedder heap tracer for the isolate. * SetEmbedderHeapTracer cannot be used simultaneously with AttachCppHeap. */ void SetEmbedderHeapTracer(EmbedderHeapTracer* tracer); /* * Gets the currently active heap tracer for the isolate that was set with * SetEmbedderHeapTracer. */ EmbedderHeapTracer* GetEmbedderHeapTracer(); /** * Sets an embedder roots handle that V8 should consider when performing * non-unified heap garbage collections. * * Using only EmbedderHeapTracer automatically sets up a default handler. * The intended use case is for setting a custom handler after invoking * `AttachCppHeap()`. * * V8 does not take ownership of the handler. */ void SetEmbedderRootsHandler(EmbedderRootsHandler* handler); /** * Attaches a managed C++ heap as an extension to the JavaScript heap. The * embedder maintains ownership of the CppHeap. At most one C++ heap can be * attached to V8. * AttachCppHeap cannot be used simultaneously with SetEmbedderHeapTracer. * * This is an experimental feature and may still change significantly. */ void AttachCppHeap(CppHeap*); /** * Detaches a managed C++ heap if one was attached using `AttachCppHeap()`. * * This is an experimental feature and may still change significantly. */ void DetachCppHeap(); /** * This is an experimental feature and may still change significantly. * \returns the C++ heap managed by V8. Only available if such a heap has been * attached using `AttachCppHeap()`. */ CppHeap* GetCppHeap() const; /** * Use for |AtomicsWaitCallback| to indicate the type of event it receives. */ enum class AtomicsWaitEvent { /** Indicates that this call is happening before waiting. */ kStartWait, /** `Atomics.wait()` finished because of an `Atomics.wake()` call. */ kWokenUp, /** `Atomics.wait()` finished because it timed out. */ kTimedOut, /** `Atomics.wait()` was interrupted through |TerminateExecution()|. */ kTerminatedExecution, /** `Atomics.wait()` was stopped through |AtomicsWaitWakeHandle|. */ kAPIStopped, /** `Atomics.wait()` did not wait, as the initial condition was not met. */ kNotEqual }; /** * Passed to |AtomicsWaitCallback| as a means of stopping an ongoing * `Atomics.wait` call. */ class V8_EXPORT AtomicsWaitWakeHandle { public: /** * Stop this `Atomics.wait()` call and call the |AtomicsWaitCallback| * with |kAPIStopped|. * * This function may be called from another thread. The caller has to ensure * through proper synchronization that it is not called after * the finishing |AtomicsWaitCallback|. * * Note that the ECMAScript specification does not plan for the possibility * of wakeups that are neither coming from a timeout or an `Atomics.wake()` * call, so this may invalidate assumptions made by existing code. * The embedder may accordingly wish to schedule an exception in the * finishing |AtomicsWaitCallback|. */ void Wake(); }; /** * Embedder callback for `Atomics.wait()` that can be added through * |SetAtomicsWaitCallback|. * * This will be called just before starting to wait with the |event| value * |kStartWait| and after finishing waiting with one of the other * values of |AtomicsWaitEvent| inside of an `Atomics.wait()` call. * * |array_buffer| will refer to the underlying SharedArrayBuffer, * |offset_in_bytes| to the location of the waited-on memory address inside * the SharedArrayBuffer. * * |value| and |timeout_in_ms| will be the values passed to * the `Atomics.wait()` call. If no timeout was used, |timeout_in_ms| * will be `INFINITY`. * * In the |kStartWait| callback, |stop_handle| will be an object that * is only valid until the corresponding finishing callback and that * can be used to stop the wait process while it is happening. * * This callback may schedule exceptions, *unless* |event| is equal to * |kTerminatedExecution|. */ using AtomicsWaitCallback = void (*)(AtomicsWaitEvent event, Local<SharedArrayBuffer> array_buffer, size_t offset_in_bytes, int64_t value, double timeout_in_ms, AtomicsWaitWakeHandle* stop_handle, void* data); /** * Set a new |AtomicsWaitCallback|. This overrides an earlier * |AtomicsWaitCallback|, if there was any. If |callback| is nullptr, * this unsets the callback. |data| will be passed to the callback * as its last parameter. */ void SetAtomicsWaitCallback(AtomicsWaitCallback callback, void* data); /** * Enables the host application to receive a notification after a * garbage collection. Allocations are allowed in the callback function, * but the callback is not re-entrant: if the allocation inside it will * trigger the garbage collection, the callback won't be called again. * It is possible to specify the GCType filter for your callback. But it is * not possible to register the same callback function two times with * different GCType filters. */ void AddGCEpilogueCallback(GCCallbackWithData callback, void* data = nullptr, GCType gc_type_filter = kGCTypeAll); void AddGCEpilogueCallback(GCCallback callback, GCType gc_type_filter = kGCTypeAll); /** * This function removes callback which was installed by * AddGCEpilogueCallback function. */ void RemoveGCEpilogueCallback(GCCallbackWithData callback, void* data = nullptr); void RemoveGCEpilogueCallback(GCCallback callback); using GetExternallyAllocatedMemoryInBytesCallback = size_t (*)(); /** * Set the callback that tells V8 how much memory is currently allocated * externally of the V8 heap. Ideally this memory is somehow connected to V8 * objects and may get freed-up when the corresponding V8 objects get * collected by a V8 garbage collection. */ void SetGetExternallyAllocatedMemoryInBytesCallback( GetExternallyAllocatedMemoryInBytesCallback callback); /** * Forcefully terminate the current thread of JavaScript execution * in the given isolate. * * This method can be used by any thread even if that thread has not * acquired the V8 lock with a Locker object. */ void TerminateExecution(); /** * Is V8 terminating JavaScript execution. * * Returns true if JavaScript execution is currently terminating * because of a call to TerminateExecution. In that case there are * still JavaScript frames on the stack and the termination * exception is still active. */ bool IsExecutionTerminating(); /** * Resume execution capability in the given isolate, whose execution * was previously forcefully terminated using TerminateExecution(). * * When execution is forcefully terminated using TerminateExecution(), * the isolate can not resume execution until all JavaScript frames * have propagated the uncatchable exception which is generated. This * method allows the program embedding the engine to handle the * termination event and resume execution capability, even if * JavaScript frames remain on the stack. * * This method can be used by any thread even if that thread has not * acquired the V8 lock with a Locker object. */ void CancelTerminateExecution(); /** * Request V8 to interrupt long running JavaScript code and invoke * the given |callback| passing the given |data| to it. After |callback| * returns control will be returned to the JavaScript code. * There may be a number of interrupt requests in flight. * Can be called from another thread without acquiring a |Locker|. * Registered |callback| must not reenter interrupted Isolate. */ void RequestInterrupt(InterruptCallback callback, void* data); /** * Returns true if there is ongoing background work within V8 that will * eventually post a foreground task, like asynchronous WebAssembly * compilation. */ bool HasPendingBackgroundTasks(); /** * Request garbage collection in this Isolate. It is only valid to call this * function if --expose_gc was specified. * * This should only be used for testing purposes and not to enforce a garbage * collection schedule. It has strong negative impact on the garbage * collection performance. Use IdleNotificationDeadline() or * LowMemoryNotification() instead to influence the garbage collection * schedule. */ void RequestGarbageCollectionForTesting(GarbageCollectionType type); /** * Request garbage collection with a specific embedderstack state in this * Isolate. It is only valid to call this function if --expose_gc was * specified. * * This should only be used for testing purposes and not to enforce a garbage * collection schedule. It has strong negative impact on the garbage * collection performance. Use IdleNotificationDeadline() or * LowMemoryNotification() instead to influence the garbage collection * schedule. */ void RequestGarbageCollectionForTesting( GarbageCollectionType type, EmbedderHeapTracer::EmbedderStackState stack_state); /** * Set the callback to invoke for logging event. */ void SetEventLogger(LogEventCallback that); /** * Adds a callback to notify the host application right before a script * is about to run. If a script re-enters the runtime during executing, the * BeforeCallEnteredCallback is invoked for each re-entrance. * Executing scripts inside the callback will re-trigger the callback. */ void AddBeforeCallEnteredCallback(BeforeCallEnteredCallback callback); /** * Removes callback that was installed by AddBeforeCallEnteredCallback. */ void RemoveBeforeCallEnteredCallback(BeforeCallEnteredCallback callback); /** * Adds a callback to notify the host application when a script finished * running. If a script re-enters the runtime during executing, the * CallCompletedCallback is only invoked when the outer-most script * execution ends. Executing scripts inside the callback do not trigger * further callbacks. */ void AddCallCompletedCallback(CallCompletedCallback callback); /** * Removes callback that was installed by AddCallCompletedCallback. */ void RemoveCallCompletedCallback(CallCompletedCallback callback); /** * Set the PromiseHook callback for various promise lifecycle * events. */ void SetPromiseHook(PromiseHook hook); /** * Set callback to notify about promise reject with no handler, or * revocation of such a previous notification once the handler is added. */ void SetPromiseRejectCallback(PromiseRejectCallback callback); /** * Runs the default MicrotaskQueue until it gets empty and perform other * microtask checkpoint steps, such as calling ClearKeptObjects. Asserts that * the MicrotasksPolicy is not kScoped. Any exceptions thrown by microtask * callbacks are swallowed. */ void PerformMicrotaskCheckpoint(); /** * Enqueues the callback to the default MicrotaskQueue */ void EnqueueMicrotask(Local<Function> microtask); /** * Enqueues the callback to the default MicrotaskQueue */ void EnqueueMicrotask(MicrotaskCallback callback, void* data = nullptr); /** * Controls how Microtasks are invoked. See MicrotasksPolicy for details. */ void SetMicrotasksPolicy(MicrotasksPolicy policy); /** * Returns the policy controlling how Microtasks are invoked. */ MicrotasksPolicy GetMicrotasksPolicy() const; /** * Adds a callback to notify the host application after * microtasks were run on the default MicrotaskQueue. The callback is * triggered by explicit RunMicrotasks call or automatic microtasks execution * (see SetMicrotaskPolicy). * * Callback will trigger even if microtasks were attempted to run, * but the microtasks queue was empty and no single microtask was actually * executed. * * Executing scripts inside the callback will not re-trigger microtasks and * the callback. */ void AddMicrotasksCompletedCallback( MicrotasksCompletedCallbackWithData callback, void* data = nullptr); /** * Removes callback that was installed by AddMicrotasksCompletedCallback. */ void RemoveMicrotasksCompletedCallback( MicrotasksCompletedCallbackWithData callback, void* data = nullptr); /** * Sets a callback for counting the number of times a feature of V8 is used. */ void SetUseCounterCallback(UseCounterCallback callback); /** * Enables the host application to provide a mechanism for recording * statistics counters. */ void SetCounterFunction(CounterLookupCallback); /** * Enables the host application to provide a mechanism for recording * histograms. The CreateHistogram function returns a * histogram which will later be passed to the AddHistogramSample * function. */ void SetCreateHistogramFunction(CreateHistogramCallback); void SetAddHistogramSampleFunction(AddHistogramSampleCallback); /** * Enables the host application to provide a mechanism for recording * event based metrics. In order to use this interface * include/v8-metrics.h * needs to be included and the recorder needs to be derived from the * Recorder base class defined there. * This method can only be called once per isolate and must happen during * isolate initialization before background threads are spawned. */ void SetMetricsRecorder( const std::shared_ptr<metrics::Recorder>& metrics_recorder); /** * Enables the host application to provide a mechanism for recording a * predefined set of data as crash keys to be used in postmortem debugging in * case of a crash. */ void SetAddCrashKeyCallback(AddCrashKeyCallback); /** * Optional notification that the embedder is idle. * V8 uses the notification to perform garbage collection. * This call can be used repeatedly if the embedder remains idle. * Returns true if the embedder should stop calling IdleNotificationDeadline * until real work has been done. This indicates that V8 has done * as much cleanup as it will be able to do. * * The deadline_in_seconds argument specifies the deadline V8 has to finish * garbage collection work. deadline_in_seconds is compared with * MonotonicallyIncreasingTime() and should be based on the same timebase as * that function. There is no guarantee that the actual work will be done * within the time limit. */ bool IdleNotificationDeadline(double deadline_in_seconds); /** * Optional notification that the system is running low on memory. * V8 uses these notifications to attempt to free memory. */ void LowMemoryNotification(); /** * Optional notification that a context has been disposed. V8 uses these * notifications to guide the GC heuristic and cancel FinalizationRegistry * cleanup tasks. Returns the number of context disposals - including this one * - since the last time V8 had a chance to clean up. * * The optional parameter |dependant_context| specifies whether the disposed * context was depending on state from other contexts or not. */ int ContextDisposedNotification(bool dependant_context = true); /** * Optional notification that the isolate switched to the foreground. * V8 uses these notifications to guide heuristics. */ void IsolateInForegroundNotification(); /** * Optional notification that the isolate switched to the background. * V8 uses these notifications to guide heuristics. */ void IsolateInBackgroundNotification(); /** * Optional notification which will enable the memory savings mode. * V8 uses this notification to guide heuristics which may result in a * smaller memory footprint at the cost of reduced runtime performance. */ void EnableMemorySavingsMode(); /** * Optional notification which will disable the memory savings mode. */ void DisableMemorySavingsMode(); /** * Optional notification to tell V8 the current performance requirements * of the embedder based on RAIL. * V8 uses these notifications to guide heuristics. * This is an unfinished experimental feature. Semantics and implementation * may change frequently. */ void SetRAILMode(RAILMode rail_mode); /** * Update load start time of the RAIL mode */ void UpdateLoadStartTime(); /** * Optional notification to tell V8 the current isolate is used for debugging * and requires higher heap limit. */ void IncreaseHeapLimitForDebugging(); /** * Restores the original heap limit after IncreaseHeapLimitForDebugging(). */ void RestoreOriginalHeapLimit(); /** * Returns true if the heap limit was increased for debugging and the * original heap limit was not restored yet. */ bool IsHeapLimitIncreasedForDebugging(); /** * Allows the host application to provide the address of a function that is * notified each time code is added, moved or removed. * * \param options options for the JIT code event handler. * \param event_handler the JIT code event handler, which will be invoked * each time code is added, moved or removed. * \note \p event_handler won't get notified of existent code. * \note since code removal notifications are not currently issued, the * \p event_handler may get notifications of code that overlaps earlier * code notifications. This happens when code areas are reused, and the * earlier overlapping code areas should therefore be discarded. * \note the events passed to \p event_handler and the strings they point to * are not guaranteed to live past each call. The \p event_handler must * copy strings and other parameters it needs to keep around. * \note the set of events declared in JitCodeEvent::EventType is expected to * grow over time, and the JitCodeEvent structure is expected to accrue * new members. The \p event_handler function must ignore event codes * it does not recognize to maintain future compatibility. * \note Use Isolate::CreateParams to get events for code executed during * Isolate setup. */ void SetJitCodeEventHandler(JitCodeEventOptions options, JitCodeEventHandler event_handler); /** * Modifies the stack limit for this Isolate. * * \param stack_limit An address beyond which the Vm's stack may not grow. * * \note If you are using threads then you should hold the V8::Locker lock * while setting the stack limit and you must set a non-default stack * limit separately for each thread. */ void SetStackLimit(uintptr_t stack_limit); /** * Returns a memory range that can potentially contain jitted code. Code for * V8's 'builtins' will not be in this range if embedded builtins is enabled. * * On Win64, embedders are advised to install function table callbacks for * these ranges, as default SEH won't be able to unwind through jitted code. * The first page of the code range is reserved for the embedder and is * committed, writable, and executable, to be used to store unwind data, as * documented in * https://docs.microsoft.com/en-us/cpp/build/exception-handling-x64. * * Might be empty on other platforms. * * https://code.google.com/p/v8/issues/detail?id=3598 */ void GetCodeRange(void** start, size_t* length_in_bytes); /** * As GetCodeRange, but for embedded builtins (these live in a distinct * memory region from other V8 Code objects). */ void GetEmbeddedCodeRange(const void** start, size_t* length_in_bytes); /** * Returns the JSEntryStubs necessary for use with the Unwinder API. */ JSEntryStubs GetJSEntryStubs(); static constexpr size_t kMinCodePagesBufferSize = 32; /** * Copies the code heap pages currently in use by V8 into |code_pages_out|. * |code_pages_out| must have at least kMinCodePagesBufferSize capacity and * must be empty. * * Signal-safe, does not allocate, does not access the V8 heap. * No code on the stack can rely on pages that might be missing. * * Returns the number of pages available to be copied, which might be greater * than |capacity|. In this case, only |capacity| pages will be copied into * |code_pages_out|. The caller should provide a bigger buffer on the next * call in order to get all available code pages, but this is not required. */ size_t CopyCodePages(size_t capacity, MemoryRange* code_pages_out); /** Set the callback to invoke in case of fatal errors. */ void SetFatalErrorHandler(FatalErrorCallback that); /** Set the callback to invoke in case of OOM errors. */ void SetOOMErrorHandler(OOMErrorCallback that); /** * Add a callback to invoke in case the heap size is close to the heap limit. * If multiple callbacks are added, only the most recently added callback is * invoked. */ void AddNearHeapLimitCallback(NearHeapLimitCallback callback, void* data); /** * Remove the given callback and restore the heap limit to the * given limit. If the given limit is zero, then it is ignored. * If the current heap size is greater than the given limit, * then the heap limit is restored to the minimal limit that * is possible for the current heap size. */ void RemoveNearHeapLimitCallback(NearHeapLimitCallback callback, size_t heap_limit); /** * If the heap limit was changed by the NearHeapLimitCallback, then the * initial heap limit will be restored once the heap size falls below the * given threshold percentage of the initial heap limit. * The threshold percentage is a number in (0.0, 1.0) range. */ void AutomaticallyRestoreInitialHeapLimit(double threshold_percent = 0.5); /** * Set the callback to invoke to check if code generation from * strings should be allowed. */ void SetModifyCodeGenerationFromStringsCallback( ModifyCodeGenerationFromStringsCallback2 callback); /** * Set the callback to invoke to check if wasm code generation should * be allowed. */ void SetAllowWasmCodeGenerationCallback( AllowWasmCodeGenerationCallback callback); /** * Embedder over{ride|load} injection points for wasm APIs. The expectation * is that the embedder sets them at most once. */ void SetWasmModuleCallback(ExtensionCallback callback); void SetWasmInstanceCallback(ExtensionCallback callback); void SetWasmStreamingCallback(WasmStreamingCallback callback); void SetWasmLoadSourceMapCallback(WasmLoadSourceMapCallback callback); void SetWasmSimdEnabledCallback(WasmSimdEnabledCallback callback); void SetWasmExceptionsEnabledCallback(WasmExceptionsEnabledCallback callback); void SetWasmDynamicTieringEnabledCallback( WasmDynamicTieringEnabledCallback callback); void SetSharedArrayBufferConstructorEnabledCallback( SharedArrayBufferConstructorEnabledCallback callback); /** * This function can be called by the embedder to signal V8 that the dynamic * enabling of features has finished. V8 can now set up dynamically added * features. */ void InstallConditionalFeatures(Local<Context> context); /** * Check if V8 is dead and therefore unusable. This is the case after * fatal errors such as out-of-memory situations. */ bool IsDead(); /** * Adds a message listener (errors only). * * The same message listener can be added more than once and in that * case it will be called more than once for each message. * * If data is specified, it will be passed to the callback when it is called. * Otherwise, the exception object will be passed to the callback instead. */ bool AddMessageListener(MessageCallback that, Local<Value> data = Local<Value>()); /** * Adds a message listener. * * The same message listener can be added more than once and in that * case it will be called more than once for each message. * * If data is specified, it will be passed to the callback when it is called. * Otherwise, the exception object will be passed to the callback instead. * * A listener can listen for particular error levels by providing a mask. */ bool AddMessageListenerWithErrorLevel(MessageCallback that, int message_levels, Local<Value> data = Local<Value>()); /** * Remove all message listeners from the specified callback function. */ void RemoveMessageListeners(MessageCallback that); /** Callback function for reporting failed access checks.*/ void SetFailedAccessCheckCallbackFunction(FailedAccessCheckCallback); /** * Tells V8 to capture current stack trace when uncaught exception occurs * and report it to the message listeners. The option is off by default. */ void SetCaptureStackTraceForUncaughtExceptions( bool capture, int frame_limit = 10, StackTrace::StackTraceOptions options = StackTrace::kOverview); /** * Iterates through all external resources referenced from current isolate * heap. GC is not invoked prior to iterating, therefore there is no * guarantee that visited objects are still alive. */ void VisitExternalResources(ExternalResourceVisitor* visitor); /** * Iterates through all the persistent handles in the current isolate's heap * that have class_ids. */ void VisitHandlesWithClassIds(PersistentHandleVisitor* visitor); /** * Iterates through all the persistent handles in the current isolate's heap * that have class_ids and are weak to be marked as inactive if there is no * pending activity for the handle. */ void VisitWeakHandles(PersistentHandleVisitor* visitor); /** * Check if this isolate is in use. * True if at least one thread Enter'ed this isolate. */ bool IsInUse(); /** * Set whether calling Atomics.wait (a function that may block) is allowed in * this isolate. This can also be configured via * CreateParams::allow_atomics_wait. */ void SetAllowAtomicsWait(bool allow); /** * Time zone redetection indicator for * DateTimeConfigurationChangeNotification. * * kSkip indicates V8 that the notification should not trigger redetecting * host time zone. kRedetect indicates V8 that host time zone should be * redetected, and used to set the default time zone. * * The host time zone detection may require file system access or similar * operations unlikely to be available inside a sandbox. If v8 is run inside a * sandbox, the host time zone has to be detected outside the sandbox before * calling DateTimeConfigurationChangeNotification function. */ enum class TimeZoneDetection { kSkip, kRedetect }; /** * Notification that the embedder has changed the time zone, daylight savings * time or other date / time configuration parameters. V8 keeps a cache of * various values used for date / time computation. This notification will * reset those cached values for the current context so that date / time * configuration changes would be reflected. * * This API should not be called more than needed as it will negatively impact * the performance of date operations. */ void DateTimeConfigurationChangeNotification( TimeZoneDetection time_zone_detection = TimeZoneDetection::kSkip); /** * Notification that the embedder has changed the locale. V8 keeps a cache of * various values used for locale computation. This notification will reset * those cached values for the current context so that locale configuration * changes would be reflected. * * This API should not be called more than needed as it will negatively impact * the performance of locale operations. */ void LocaleConfigurationChangeNotification(); Isolate() = delete; ~Isolate() = delete; Isolate(const Isolate&) = delete; Isolate& operator=(const Isolate&) = delete; // Deleting operator new and delete here is allowed as ctor and dtor is also // deleted. void* operator new(size_t size) = delete; void* operator new[](size_t size) = delete; void operator delete(void*, size_t) = delete; void operator delete[](void*, size_t) = delete; private: template <class K, class V, class Traits> friend class PersistentValueMapBase; internal::Address* GetDataFromSnapshotOnce(size_t index); void ReportExternalAllocationLimitReached(); }; void Isolate::SetData(uint32_t slot, void* data) { using I = internal::Internals; I::SetEmbedderData(this, slot, data); } void* Isolate::GetData(uint32_t slot) { using I = internal::Internals; return I::GetEmbedderData(this, slot); } uint32_t Isolate::GetNumberOfDataSlots() { using I = internal::Internals; return I::kNumIsolateDataSlots; } template <class T> MaybeLocal<T> Isolate::GetDataFromSnapshotOnce(size_t index) { T* data = reinterpret_cast<T*>(GetDataFromSnapshotOnce(index)); if (data) internal::PerformCastCheck(data); return Local<T>(data); } } // namespace v8 #endif // INCLUDE_V8_ISOLATE_H_
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