mirror of
https://github.com/denoland/rusty_v8.git
synced 2025-01-14 01:50:24 -05:00
d3fff51d2d
Removing this garbage collection trigger removes the guarantee that "regular" FinalizerCallbacks will be called before the isolate goes away. It is fine as both spec and V8 do not provide this guarantee and we were overly strict in this case.
1805 lines
57 KiB
Rust
1805 lines
57 KiB
Rust
// Copyright 2019-2021 the Deno authors. All rights reserved. MIT license.
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use crate::function::FunctionCallbackInfo;
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use crate::gc::GCCallbackFlags;
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use crate::gc::GCType;
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use crate::handle::FinalizerCallback;
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use crate::handle::FinalizerMap;
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use crate::isolate_create_params::raw;
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use crate::isolate_create_params::CreateParams;
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use crate::promise::PromiseRejectMessage;
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use crate::scope::data::ScopeData;
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use crate::snapshot::SnapshotCreator;
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use crate::support::char;
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use crate::support::int;
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use crate::support::Allocated;
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use crate::support::MapFnFrom;
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use crate::support::MapFnTo;
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use crate::support::Opaque;
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use crate::support::ToCFn;
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use crate::support::UnitType;
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use crate::wasm::trampoline;
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use crate::wasm::WasmStreaming;
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use crate::Array;
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use crate::CallbackScope;
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use crate::Context;
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use crate::Data;
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use crate::ExternalReferences;
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use crate::FixedArray;
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use crate::Function;
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use crate::FunctionCodeHandling;
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use crate::HandleScope;
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use crate::Local;
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use crate::Message;
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use crate::Module;
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use crate::Object;
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use crate::Promise;
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use crate::PromiseResolver;
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use crate::StartupData;
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use crate::String;
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use crate::Value;
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use std::any::Any;
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use std::any::TypeId;
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use std::collections::HashMap;
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use std::ffi::c_void;
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use std::fmt::{self, Debug, Formatter};
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use std::hash::BuildHasher;
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use std::hash::Hasher;
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use std::mem::align_of;
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use std::mem::forget;
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use std::mem::needs_drop;
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use std::mem::size_of;
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use std::mem::MaybeUninit;
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use std::ops::Deref;
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use std::ops::DerefMut;
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use std::ptr;
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use std::ptr::drop_in_place;
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use std::ptr::null_mut;
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use std::ptr::NonNull;
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use std::sync::Arc;
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use std::sync::Mutex;
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/// Policy for running microtasks:
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/// - explicit: microtasks are invoked with the
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/// Isolate::PerformMicrotaskCheckpoint() method;
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/// - auto: microtasks are invoked when the script call depth decrements
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/// to zero.
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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#[repr(C)]
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pub enum MicrotasksPolicy {
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Explicit = 0,
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// Scoped = 1 (RAII) is omitted for now, doesn't quite map to idiomatic Rust.
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Auto = 2,
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}
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/// Memory pressure level for the MemoryPressureNotification.
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/// None hints V8 that there is no memory pressure.
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/// Moderate hints V8 to speed up incremental garbage collection at the cost
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/// of higher latency due to garbage collection pauses.
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/// Critical hints V8 to free memory as soon as possible. Garbage collection
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/// pauses at this level will be large.
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pub enum MemoryPressureLevel {
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None = 0,
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Moderate = 1,
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Critical = 2,
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}
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/// PromiseHook with type Init is called when a new promise is
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/// created. When a new promise is created as part of the chain in the
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/// case of Promise.then or in the intermediate promises created by
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/// Promise.{race, all}/AsyncFunctionAwait, we pass the parent promise
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/// otherwise we pass undefined.
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///
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/// PromiseHook with type Resolve is called at the beginning of
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/// resolve or reject function defined by CreateResolvingFunctions.
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///
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/// PromiseHook with type Before is called at the beginning of the
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/// PromiseReactionJob.
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///
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/// PromiseHook with type After is called right at the end of the
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/// PromiseReactionJob.
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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#[repr(C)]
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pub enum PromiseHookType {
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Init,
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Resolve,
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Before,
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After,
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}
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/// Types of garbage collections that can be requested via
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/// [`Isolate::request_garbage_collection_for_testing`].
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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#[repr(C)]
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pub enum GarbageCollectionType {
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Full,
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Minor,
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}
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pub type MessageCallback = extern "C" fn(Local<Message>, Local<Value>);
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pub type PromiseHook =
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extern "C" fn(PromiseHookType, Local<Promise>, Local<Value>);
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pub type PromiseRejectCallback = extern "C" fn(PromiseRejectMessage);
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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#[repr(C)]
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pub enum WasmAsyncSuccess {
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Success,
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Fail,
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}
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pub type WasmAsyncResolvePromiseCallback = extern "C" fn(
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*mut Isolate,
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Local<Context>,
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Local<PromiseResolver>,
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Local<Value>,
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WasmAsyncSuccess,
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);
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/// HostInitializeImportMetaObjectCallback is called the first time import.meta
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/// is accessed for a module. Subsequent access will reuse the same value.
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///
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/// The method combines two implementation-defined abstract operations into one:
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/// HostGetImportMetaProperties and HostFinalizeImportMeta.
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///
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/// The embedder should use v8::Object::CreateDataProperty to add properties on
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/// the meta object.
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pub type HostInitializeImportMetaObjectCallback =
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extern "C" fn(Local<Context>, Local<Module>, Local<Object>);
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/// HostImportModuleDynamicallyCallback is called when we require the embedder
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/// to load a module. This is used as part of the dynamic import syntax.
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///
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/// The referrer contains metadata about the script/module that calls import.
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///
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/// The specifier is the name of the module that should be imported.
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///
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/// The import_assertions are import assertions for this request in the form:
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/// [key1, value1, key2, value2, ...] where the keys and values are of type
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/// v8::String. Note, unlike the FixedArray passed to ResolveModuleCallback and
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/// returned from ModuleRequest::GetImportAssertions(), this array does not
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/// contain the source Locations of the assertions.
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///
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/// The embedder must compile, instantiate, evaluate the Module, and obtain its
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/// namespace object.
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///
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/// The Promise returned from this function is forwarded to userland JavaScript.
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/// The embedder must resolve this promise with the module namespace object. In
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/// case of an exception, the embedder must reject this promise with the
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/// exception. If the promise creation itself fails (e.g. due to stack
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/// overflow), the embedder must propagate that exception by returning an empty
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/// MaybeLocal.
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///
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/// # Example
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///
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/// ```
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/// fn host_import_module_dynamically_callback_example<'s>(
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/// scope: &mut v8::HandleScope<'s>,
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/// host_defined_options: v8::Local<'s, v8::Data>,
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/// resource_name: v8::Local<'s, v8::Value>,
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/// specifier: v8::Local<'s, v8::String>,
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/// import_assertions: v8::Local<'s, v8::FixedArray>,
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/// ) -> Option<v8::Local<'s, v8::Promise>> {
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/// todo!()
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/// }
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/// ```
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pub trait HostImportModuleDynamicallyCallback:
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UnitType
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+ for<'s> FnOnce(
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&mut HandleScope<'s>,
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Local<'s, Data>,
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Local<'s, Value>,
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Local<'s, String>,
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Local<'s, FixedArray>,
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) -> Option<Local<'s, Promise>>
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{
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fn to_c_fn(self) -> RawHostImportModuleDynamicallyCallback;
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}
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#[cfg(target_family = "unix")]
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pub(crate) type RawHostImportModuleDynamicallyCallback =
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for<'s> extern "C" fn(
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Local<'s, Context>,
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Local<'s, Data>,
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Local<'s, Value>,
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Local<'s, String>,
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Local<'s, FixedArray>,
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) -> *mut Promise;
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#[cfg(all(target_family = "windows", target_arch = "x86_64"))]
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pub type RawHostImportModuleDynamicallyCallback =
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for<'s> extern "C" fn(
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*mut *mut Promise,
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Local<'s, Context>,
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Local<'s, Data>,
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Local<'s, Value>,
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Local<'s, String>,
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Local<'s, FixedArray>,
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) -> *mut *mut Promise;
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impl<F> HostImportModuleDynamicallyCallback for F
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where
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F: UnitType
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+ for<'s> FnOnce(
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&mut HandleScope<'s>,
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Local<'s, Data>,
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Local<'s, Value>,
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Local<'s, String>,
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Local<'s, FixedArray>,
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) -> Option<Local<'s, Promise>>,
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{
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#[inline(always)]
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fn to_c_fn(self) -> RawHostImportModuleDynamicallyCallback {
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#[inline(always)]
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fn scope_adapter<'s, F: HostImportModuleDynamicallyCallback>(
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context: Local<'s, Context>,
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host_defined_options: Local<'s, Data>,
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resource_name: Local<'s, Value>,
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specifier: Local<'s, String>,
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import_assertions: Local<'s, FixedArray>,
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) -> Option<Local<'s, Promise>> {
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let scope = &mut unsafe { CallbackScope::new(context) };
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(F::get())(
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scope,
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host_defined_options,
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resource_name,
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specifier,
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import_assertions,
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)
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}
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#[cfg(target_family = "unix")]
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#[inline(always)]
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extern "C" fn abi_adapter<'s, F: HostImportModuleDynamicallyCallback>(
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context: Local<'s, Context>,
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host_defined_options: Local<'s, Data>,
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resource_name: Local<'s, Value>,
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specifier: Local<'s, String>,
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import_assertions: Local<'s, FixedArray>,
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) -> *mut Promise {
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scope_adapter::<F>(
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context,
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host_defined_options,
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resource_name,
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specifier,
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import_assertions,
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)
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.map(|return_value| return_value.as_non_null().as_ptr())
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.unwrap_or_else(null_mut)
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}
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#[cfg(all(target_family = "windows", target_arch = "x86_64"))]
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#[inline(always)]
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extern "C" fn abi_adapter<'s, F: HostImportModuleDynamicallyCallback>(
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return_value: *mut *mut Promise,
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context: Local<'s, Context>,
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host_defined_options: Local<'s, Data>,
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resource_name: Local<'s, Value>,
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specifier: Local<'s, String>,
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import_assertions: Local<'s, FixedArray>,
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) -> *mut *mut Promise {
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unsafe {
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std::ptr::write(
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return_value,
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scope_adapter::<F>(
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context,
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host_defined_options,
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resource_name,
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specifier,
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import_assertions,
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)
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.map(|return_value| return_value.as_non_null().as_ptr())
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.unwrap_or_else(null_mut),
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);
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return_value
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}
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}
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abi_adapter::<F>
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}
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}
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/// `HostCreateShadowRealmContextCallback` is called each time a `ShadowRealm`
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/// is being constructed. You can use [`HandleScope::get_current_context`] to
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/// get the [`Context`] in which the constructor is being run.
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///
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/// The method combines [`Context`] creation and the implementation-defined
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/// abstract operation `HostInitializeShadowRealm` into one.
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///
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/// The embedder should use [`Context::new`] to create a new context. If the
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/// creation fails, the embedder must propagate that exception by returning
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/// [`None`].
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pub type HostCreateShadowRealmContextCallback =
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for<'s> fn(scope: &mut HandleScope<'s>) -> Option<Local<'s, Context>>;
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pub type GcCallbackWithData = extern "C" fn(
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isolate: *mut Isolate,
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r#type: GCType,
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flags: GCCallbackFlags,
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data: *mut c_void,
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);
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pub type InterruptCallback =
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extern "C" fn(isolate: &mut Isolate, data: *mut c_void);
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pub type NearHeapLimitCallback = extern "C" fn(
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data: *mut c_void,
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current_heap_limit: usize,
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initial_heap_limit: usize,
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) -> usize;
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#[repr(C)]
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pub struct OomDetails {
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pub is_heap_oom: bool,
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pub detail: *const char,
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}
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pub type OomErrorCallback =
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extern "C" fn(location: *const char, details: &OomDetails);
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/// Collection of V8 heap information.
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///
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/// Instances of this class can be passed to v8::Isolate::GetHeapStatistics to
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/// get heap statistics from V8.
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// Must be >= sizeof(v8::HeapStatistics), see v8__HeapStatistics__CONSTRUCT().
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#[repr(C)]
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#[derive(Debug)]
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pub struct HeapStatistics([usize; 16]);
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// Windows x64 ABI: MaybeLocal<Value> returned on the stack.
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#[cfg(target_os = "windows")]
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pub type PrepareStackTraceCallback<'s> = extern "C" fn(
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*mut *const Value,
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Local<'s, Context>,
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Local<'s, Value>,
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Local<'s, Array>,
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) -> *mut *const Value;
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// System V ABI: MaybeLocal<Value> returned in a register.
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// System V i386 ABI: Local<Value> returned in hidden pointer (struct).
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#[cfg(not(target_os = "windows"))]
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#[repr(C)]
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pub struct PrepareStackTraceCallbackRet(*const Value);
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#[cfg(not(target_os = "windows"))]
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pub type PrepareStackTraceCallback<'s> =
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extern "C" fn(
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Local<'s, Context>,
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Local<'s, Value>,
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Local<'s, Array>,
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) -> PrepareStackTraceCallbackRet;
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extern "C" {
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static v8__internal__Internals__kIsolateEmbedderDataOffset: int;
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fn v8__Isolate__New(params: *const raw::CreateParams) -> *mut Isolate;
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fn v8__Isolate__Dispose(this: *mut Isolate);
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fn v8__Isolate__GetNumberOfDataSlots(this: *const Isolate) -> u32;
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fn v8__Isolate__Enter(this: *mut Isolate);
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fn v8__Isolate__Exit(this: *mut Isolate);
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|
fn v8__Isolate__MemoryPressureNotification(this: *mut Isolate, level: u8);
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fn v8__Isolate__ClearKeptObjects(isolate: *mut Isolate);
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fn v8__Isolate__LowMemoryNotification(isolate: *mut Isolate);
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|
fn v8__Isolate__GetHeapStatistics(this: *mut Isolate, s: *mut HeapStatistics);
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|
fn v8__Isolate__SetCaptureStackTraceForUncaughtExceptions(
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|
this: *mut Isolate,
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|
caputre: bool,
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|
frame_limit: i32,
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|
);
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|
fn v8__Isolate__AddMessageListener(
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|
isolate: *mut Isolate,
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|
callback: MessageCallback,
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|
) -> bool;
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|
fn v8__Isolate__AddGCPrologueCallback(
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|
isolate: *mut Isolate,
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|
callback: GcCallbackWithData,
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|
data: *mut c_void,
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|
gc_type_filter: GCType,
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|
);
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|
fn v8__Isolate__RemoveGCPrologueCallback(
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|
isolate: *mut Isolate,
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|
callback: GcCallbackWithData,
|
|
data: *mut c_void,
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|
);
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|
fn v8__Isolate__AddNearHeapLimitCallback(
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|
isolate: *mut Isolate,
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|
callback: NearHeapLimitCallback,
|
|
data: *mut c_void,
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|
);
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|
fn v8__Isolate__RemoveNearHeapLimitCallback(
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|
isolate: *mut Isolate,
|
|
callback: NearHeapLimitCallback,
|
|
heap_limit: usize,
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|
);
|
|
fn v8__Isolate__SetOOMErrorHandler(
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|
isolate: *mut Isolate,
|
|
callback: OomErrorCallback,
|
|
);
|
|
fn v8__Isolate__AdjustAmountOfExternalAllocatedMemory(
|
|
isolate: *mut Isolate,
|
|
change_in_bytes: i64,
|
|
) -> i64;
|
|
fn v8__Isolate__SetPrepareStackTraceCallback(
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|
isolate: *mut Isolate,
|
|
callback: PrepareStackTraceCallback,
|
|
);
|
|
fn v8__Isolate__SetPromiseHook(isolate: *mut Isolate, hook: PromiseHook);
|
|
fn v8__Isolate__SetPromiseRejectCallback(
|
|
isolate: *mut Isolate,
|
|
callback: PromiseRejectCallback,
|
|
);
|
|
fn v8__Isolate__SetWasmAsyncResolvePromiseCallback(
|
|
isolate: *mut Isolate,
|
|
callback: WasmAsyncResolvePromiseCallback,
|
|
);
|
|
fn v8__Isolate__SetHostInitializeImportMetaObjectCallback(
|
|
isolate: *mut Isolate,
|
|
callback: HostInitializeImportMetaObjectCallback,
|
|
);
|
|
fn v8__Isolate__SetHostImportModuleDynamicallyCallback(
|
|
isolate: *mut Isolate,
|
|
callback: RawHostImportModuleDynamicallyCallback,
|
|
);
|
|
#[cfg(not(target_os = "windows"))]
|
|
fn v8__Isolate__SetHostCreateShadowRealmContextCallback(
|
|
isolate: *mut Isolate,
|
|
callback: extern "C" fn(initiator_context: Local<Context>) -> *mut Context,
|
|
);
|
|
#[cfg(target_os = "windows")]
|
|
fn v8__Isolate__SetHostCreateShadowRealmContextCallback(
|
|
isolate: *mut Isolate,
|
|
callback: extern "C" fn(
|
|
rv: *mut *mut Context,
|
|
initiator_context: Local<Context>,
|
|
) -> *mut *mut Context,
|
|
);
|
|
fn v8__Isolate__RequestInterrupt(
|
|
isolate: *const Isolate,
|
|
callback: InterruptCallback,
|
|
data: *mut c_void,
|
|
);
|
|
fn v8__Isolate__TerminateExecution(isolate: *const Isolate);
|
|
fn v8__Isolate__IsExecutionTerminating(isolate: *const Isolate) -> bool;
|
|
fn v8__Isolate__CancelTerminateExecution(isolate: *const Isolate);
|
|
fn v8__Isolate__GetMicrotasksPolicy(
|
|
isolate: *const Isolate,
|
|
) -> MicrotasksPolicy;
|
|
fn v8__Isolate__SetMicrotasksPolicy(
|
|
isolate: *mut Isolate,
|
|
policy: MicrotasksPolicy,
|
|
);
|
|
fn v8__Isolate__PerformMicrotaskCheckpoint(isolate: *mut Isolate);
|
|
fn v8__Isolate__EnqueueMicrotask(
|
|
isolate: *mut Isolate,
|
|
function: *const Function,
|
|
);
|
|
fn v8__Isolate__SetAllowAtomicsWait(isolate: *mut Isolate, allow: bool);
|
|
fn v8__Isolate__SetWasmStreamingCallback(
|
|
isolate: *mut Isolate,
|
|
callback: extern "C" fn(*const FunctionCallbackInfo),
|
|
);
|
|
fn v8__Isolate__HasPendingBackgroundTasks(isolate: *const Isolate) -> bool;
|
|
fn v8__Isolate__RequestGarbageCollectionForTesting(
|
|
isolate: *mut Isolate,
|
|
r#type: usize,
|
|
);
|
|
|
|
fn v8__HeapProfiler__TakeHeapSnapshot(
|
|
isolate: *mut Isolate,
|
|
callback: extern "C" fn(*mut c_void, *const u8, usize) -> bool,
|
|
arg: *mut c_void,
|
|
);
|
|
|
|
fn v8__HeapStatistics__CONSTRUCT(s: *mut MaybeUninit<HeapStatistics>);
|
|
fn v8__HeapStatistics__total_heap_size(s: *const HeapStatistics) -> usize;
|
|
fn v8__HeapStatistics__total_heap_size_executable(
|
|
s: *const HeapStatistics,
|
|
) -> usize;
|
|
fn v8__HeapStatistics__total_physical_size(s: *const HeapStatistics)
|
|
-> usize;
|
|
fn v8__HeapStatistics__total_available_size(
|
|
s: *const HeapStatistics,
|
|
) -> usize;
|
|
fn v8__HeapStatistics__total_global_handles_size(
|
|
s: *const HeapStatistics,
|
|
) -> usize;
|
|
fn v8__HeapStatistics__used_global_handles_size(
|
|
s: *const HeapStatistics,
|
|
) -> usize;
|
|
fn v8__HeapStatistics__used_heap_size(s: *const HeapStatistics) -> usize;
|
|
fn v8__HeapStatistics__heap_size_limit(s: *const HeapStatistics) -> usize;
|
|
fn v8__HeapStatistics__malloced_memory(s: *const HeapStatistics) -> usize;
|
|
fn v8__HeapStatistics__external_memory(s: *const HeapStatistics) -> usize;
|
|
fn v8__HeapStatistics__peak_malloced_memory(
|
|
s: *const HeapStatistics,
|
|
) -> usize;
|
|
fn v8__HeapStatistics__number_of_native_contexts(
|
|
s: *const HeapStatistics,
|
|
) -> usize;
|
|
fn v8__HeapStatistics__number_of_detached_contexts(
|
|
s: *const HeapStatistics,
|
|
) -> usize;
|
|
fn v8__HeapStatistics__does_zap_garbage(s: *const HeapStatistics) -> usize;
|
|
}
|
|
|
|
/// 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.
|
|
///
|
|
/// rusty_v8 note: Unlike in the C++ API, the Isolate is entered when it is
|
|
/// constructed and exited when dropped.
|
|
#[repr(C)]
|
|
#[derive(Debug)]
|
|
pub struct Isolate(Opaque);
|
|
|
|
impl Isolate {
|
|
// Total number of isolate data slots provided by V8.
|
|
const EMBEDDER_DATA_SLOT_COUNT: u32 = 4;
|
|
|
|
// Byte offset inside `Isolate` where the isolate data slots are stored. This
|
|
// should be the same as the value of `kIsolateEmbedderDataOffset` which is
|
|
// defined in `v8-internal.h`.
|
|
const EMBEDDER_DATA_OFFSET: usize = size_of::<[*const (); 23]>();
|
|
|
|
// Isolate data slots used internally by rusty_v8.
|
|
const ANNEX_SLOT: u32 = 0;
|
|
const CURRENT_SCOPE_DATA_SLOT: u32 = 1;
|
|
const INTERNAL_DATA_SLOT_COUNT: u32 = 2;
|
|
|
|
#[inline(always)]
|
|
fn assert_embedder_data_slot_count_and_offset_correct(&self) {
|
|
assert_eq!(
|
|
unsafe { v8__Isolate__GetNumberOfDataSlots(self) },
|
|
Self::EMBEDDER_DATA_SLOT_COUNT
|
|
);
|
|
assert_eq!(
|
|
unsafe { v8__internal__Internals__kIsolateEmbedderDataOffset } as usize,
|
|
Self::EMBEDDER_DATA_OFFSET
|
|
);
|
|
}
|
|
|
|
/// 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 V8::dispose(). Using the delete operator is not allowed.
|
|
///
|
|
/// V8::initialize() must have run prior to this.
|
|
#[allow(clippy::new_ret_no_self)]
|
|
pub fn new(params: CreateParams) -> OwnedIsolate {
|
|
crate::V8::assert_initialized();
|
|
let (raw_create_params, create_param_allocations) = params.finalize();
|
|
let cxx_isolate = unsafe { v8__Isolate__New(&raw_create_params) };
|
|
let mut owned_isolate = OwnedIsolate::new(cxx_isolate);
|
|
owned_isolate.assert_embedder_data_slot_count_and_offset_correct();
|
|
ScopeData::new_root(&mut owned_isolate);
|
|
owned_isolate.create_annex(create_param_allocations);
|
|
unsafe {
|
|
owned_isolate.enter();
|
|
}
|
|
owned_isolate
|
|
}
|
|
|
|
#[allow(clippy::new_ret_no_self)]
|
|
pub fn snapshot_creator(
|
|
external_references: Option<&'static ExternalReferences>,
|
|
) -> OwnedIsolate {
|
|
SnapshotCreator::new(external_references)
|
|
}
|
|
|
|
#[allow(clippy::new_ret_no_self)]
|
|
pub fn snapshot_creator_from_existing_snapshot(
|
|
existing_snapshot_blob: impl Allocated<[u8]>,
|
|
external_references: Option<&'static ExternalReferences>,
|
|
) -> OwnedIsolate {
|
|
SnapshotCreator::from_existing_snapshot(
|
|
existing_snapshot_blob,
|
|
external_references,
|
|
)
|
|
}
|
|
|
|
/// Initial configuration parameters for a new Isolate.
|
|
#[inline(always)]
|
|
pub fn create_params() -> CreateParams {
|
|
CreateParams::default()
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn thread_safe_handle(&self) -> IsolateHandle {
|
|
IsolateHandle::new(self)
|
|
}
|
|
|
|
/// See [`IsolateHandle::terminate_execution`]
|
|
#[inline(always)]
|
|
pub fn terminate_execution(&self) -> bool {
|
|
self.thread_safe_handle().terminate_execution()
|
|
}
|
|
|
|
/// See [`IsolateHandle::cancel_terminate_execution`]
|
|
#[inline(always)]
|
|
pub fn cancel_terminate_execution(&self) -> bool {
|
|
self.thread_safe_handle().cancel_terminate_execution()
|
|
}
|
|
|
|
/// See [`IsolateHandle::is_execution_terminating`]
|
|
#[inline(always)]
|
|
pub fn is_execution_terminating(&self) -> bool {
|
|
self.thread_safe_handle().is_execution_terminating()
|
|
}
|
|
|
|
pub(crate) fn create_annex(
|
|
&mut self,
|
|
create_param_allocations: Box<dyn Any>,
|
|
) {
|
|
let annex_arc = Arc::new(IsolateAnnex::new(self, create_param_allocations));
|
|
let annex_ptr = Arc::into_raw(annex_arc);
|
|
assert!(self.get_data_internal(Self::ANNEX_SLOT).is_null());
|
|
self.set_data_internal(Self::ANNEX_SLOT, annex_ptr as *mut _);
|
|
}
|
|
|
|
#[inline(always)]
|
|
fn get_annex(&self) -> &IsolateAnnex {
|
|
let annex_ptr =
|
|
self.get_data_internal(Self::ANNEX_SLOT) as *const IsolateAnnex;
|
|
assert!(!annex_ptr.is_null());
|
|
unsafe { &*annex_ptr }
|
|
}
|
|
|
|
#[inline(always)]
|
|
fn get_annex_mut(&mut self) -> &mut IsolateAnnex {
|
|
let annex_ptr =
|
|
self.get_data_internal(Self::ANNEX_SLOT) as *mut IsolateAnnex;
|
|
assert!(!annex_ptr.is_null());
|
|
unsafe { &mut *annex_ptr }
|
|
}
|
|
|
|
pub(crate) fn set_snapshot_creator(
|
|
&mut self,
|
|
snapshot_creator: SnapshotCreator,
|
|
) {
|
|
let prev = self
|
|
.get_annex_mut()
|
|
.maybe_snapshot_creator
|
|
.replace(snapshot_creator);
|
|
assert!(prev.is_none());
|
|
}
|
|
|
|
pub(crate) fn get_finalizer_map(&self) -> &FinalizerMap {
|
|
&self.get_annex().finalizer_map
|
|
}
|
|
|
|
pub(crate) fn get_finalizer_map_mut(&mut self) -> &mut FinalizerMap {
|
|
&mut self.get_annex_mut().finalizer_map
|
|
}
|
|
|
|
fn get_annex_arc(&self) -> Arc<IsolateAnnex> {
|
|
let annex_ptr = self.get_annex();
|
|
let annex_arc = unsafe { Arc::from_raw(annex_ptr) };
|
|
let _ = Arc::into_raw(annex_arc.clone());
|
|
annex_arc
|
|
}
|
|
|
|
/// Retrieve embedder-specific data from the isolate.
|
|
/// Returns NULL if SetData has never been called for the given `slot`.
|
|
pub fn get_data(&self, slot: u32) -> *mut c_void {
|
|
self.get_data_internal(Self::INTERNAL_DATA_SLOT_COUNT + slot)
|
|
}
|
|
|
|
/// Associate embedder-specific data with the isolate. `slot` has to be
|
|
/// between 0 and `Isolate::get_number_of_data_slots()`.
|
|
#[inline(always)]
|
|
pub fn set_data(&mut self, slot: u32, data: *mut c_void) {
|
|
self.set_data_internal(Self::INTERNAL_DATA_SLOT_COUNT + slot, data)
|
|
}
|
|
|
|
/// Returns the maximum number of available embedder data slots. Valid slots
|
|
/// are in the range of `0 <= n < Isolate::get_number_of_data_slots()`.
|
|
pub fn get_number_of_data_slots(&self) -> u32 {
|
|
Self::EMBEDDER_DATA_SLOT_COUNT - Self::INTERNAL_DATA_SLOT_COUNT
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub(crate) fn get_data_internal(&self, slot: u32) -> *mut c_void {
|
|
let slots = unsafe {
|
|
let p = self as *const Self as *const u8;
|
|
let p = p.add(Self::EMBEDDER_DATA_OFFSET);
|
|
let p = p as *const [*mut c_void; Self::EMBEDDER_DATA_SLOT_COUNT as _];
|
|
&*p
|
|
};
|
|
slots[slot as usize]
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub(crate) fn set_data_internal(&mut self, slot: u32, data: *mut c_void) {
|
|
let slots = unsafe {
|
|
let p = self as *mut Self as *mut u8;
|
|
let p = p.add(Self::EMBEDDER_DATA_OFFSET);
|
|
let p = p as *mut [*mut c_void; Self::EMBEDDER_DATA_SLOT_COUNT as _];
|
|
&mut *p
|
|
};
|
|
slots[slot as usize] = data;
|
|
}
|
|
|
|
/// Returns a pointer to the `ScopeData` struct for the current scope.
|
|
#[inline(always)]
|
|
pub(crate) fn get_current_scope_data(&self) -> Option<NonNull<ScopeData>> {
|
|
let scope_data_ptr = self.get_data_internal(Self::CURRENT_SCOPE_DATA_SLOT);
|
|
NonNull::new(scope_data_ptr).map(NonNull::cast)
|
|
}
|
|
|
|
/// Updates the slot that stores a `ScopeData` pointer for the current scope.
|
|
#[inline(always)]
|
|
pub(crate) fn set_current_scope_data(
|
|
&mut self,
|
|
scope_data: Option<NonNull<ScopeData>>,
|
|
) {
|
|
let scope_data_ptr = scope_data
|
|
.map(NonNull::cast)
|
|
.map(NonNull::as_ptr)
|
|
.unwrap_or_else(null_mut);
|
|
self.set_data_internal(Self::CURRENT_SCOPE_DATA_SLOT, scope_data_ptr);
|
|
}
|
|
|
|
/// Get a reference to embedder data added with `set_slot()`.
|
|
#[inline(always)]
|
|
pub fn get_slot<T: 'static>(&self) -> Option<&T> {
|
|
self
|
|
.get_annex()
|
|
.slots
|
|
.get(&TypeId::of::<T>())
|
|
.map(|slot| unsafe { slot.borrow::<T>() })
|
|
}
|
|
|
|
/// Get a mutable reference to embedder data added with `set_slot()`.
|
|
#[inline(always)]
|
|
pub fn get_slot_mut<T: 'static>(&mut self) -> Option<&mut T> {
|
|
self
|
|
.get_annex_mut()
|
|
.slots
|
|
.get_mut(&TypeId::of::<T>())
|
|
.map(|slot| unsafe { slot.borrow_mut::<T>() })
|
|
}
|
|
|
|
/// Use with Isolate::get_slot and Isolate::get_slot_mut to associate state
|
|
/// with an Isolate.
|
|
///
|
|
/// This method gives ownership of value to the Isolate. Exactly one object of
|
|
/// each type can be associated with an Isolate. If called more than once with
|
|
/// an object of the same type, the earlier version will be dropped and
|
|
/// replaced.
|
|
///
|
|
/// Returns true if value was set without replacing an existing value.
|
|
///
|
|
/// The value will be dropped when the isolate is dropped.
|
|
#[inline(always)]
|
|
pub fn set_slot<T: 'static>(&mut self, value: T) -> bool {
|
|
self
|
|
.get_annex_mut()
|
|
.slots
|
|
.insert(TypeId::of::<T>(), RawSlot::new(value))
|
|
.is_none()
|
|
}
|
|
|
|
/// Removes the embedder data added with `set_slot()` and returns it if it exists.
|
|
#[inline(always)]
|
|
pub fn remove_slot<T: 'static>(&mut self) -> Option<T> {
|
|
self
|
|
.get_annex_mut()
|
|
.slots
|
|
.remove(&TypeId::of::<T>())
|
|
.map(|slot| unsafe { slot.into_inner::<T>() })
|
|
}
|
|
|
|
/// 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.
|
|
///
|
|
/// rusty_v8 note: Unlike in the C++ API, the isolate is entered when it is
|
|
/// constructed and exited when dropped.
|
|
#[inline(always)]
|
|
pub unsafe fn enter(&mut self) {
|
|
v8__Isolate__Enter(self)
|
|
}
|
|
|
|
/// 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: self == Isolate::GetCurrent().
|
|
///
|
|
/// rusty_v8 note: Unlike in the C++ API, the isolate is entered when it is
|
|
/// constructed and exited when dropped.
|
|
#[inline(always)]
|
|
pub unsafe fn exit(&mut self) {
|
|
v8__Isolate__Exit(self)
|
|
}
|
|
|
|
/// 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.
|
|
#[inline(always)]
|
|
pub fn memory_pressure_notification(&mut self, level: MemoryPressureLevel) {
|
|
unsafe { v8__Isolate__MemoryPressureNotification(self, level as u8) }
|
|
}
|
|
|
|
/// 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.
|
|
#[inline(always)]
|
|
pub fn clear_kept_objects(&mut self) {
|
|
unsafe { v8__Isolate__ClearKeptObjects(self) }
|
|
}
|
|
|
|
/// Optional notification that the system is running low on memory.
|
|
/// V8 uses these notifications to attempt to free memory.
|
|
#[inline(always)]
|
|
pub fn low_memory_notification(&mut self) {
|
|
unsafe { v8__Isolate__LowMemoryNotification(self) }
|
|
}
|
|
|
|
/// Get statistics about the heap memory usage.
|
|
#[inline(always)]
|
|
pub fn get_heap_statistics(&mut self, s: &mut HeapStatistics) {
|
|
unsafe { v8__Isolate__GetHeapStatistics(self, s) }
|
|
}
|
|
|
|
/// Tells V8 to capture current stack trace when uncaught exception occurs
|
|
/// and report it to the message listeners. The option is off by default.
|
|
#[inline(always)]
|
|
pub fn set_capture_stack_trace_for_uncaught_exceptions(
|
|
&mut self,
|
|
capture: bool,
|
|
frame_limit: i32,
|
|
) {
|
|
unsafe {
|
|
v8__Isolate__SetCaptureStackTraceForUncaughtExceptions(
|
|
self,
|
|
capture,
|
|
frame_limit,
|
|
)
|
|
}
|
|
}
|
|
|
|
/// 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.
|
|
///
|
|
/// The exception object will be passed to the callback.
|
|
#[inline(always)]
|
|
pub fn add_message_listener(&mut self, callback: MessageCallback) -> bool {
|
|
unsafe { v8__Isolate__AddMessageListener(self, callback) }
|
|
}
|
|
|
|
/// This specifies the callback called when the stack property of Error
|
|
/// is accessed.
|
|
///
|
|
/// PrepareStackTraceCallback is called when the stack property of an error is
|
|
/// first accessed. The return value will be used as the stack value. If this
|
|
/// callback is registed, the |Error.prepareStackTrace| API will be disabled.
|
|
/// |sites| is an array of call sites, specified in
|
|
/// https://v8.dev/docs/stack-trace-api
|
|
#[inline(always)]
|
|
pub fn set_prepare_stack_trace_callback<'s>(
|
|
&mut self,
|
|
callback: impl MapFnTo<PrepareStackTraceCallback<'s>>,
|
|
) {
|
|
// Note: the C++ API returns a MaybeLocal but V8 asserts at runtime when
|
|
// it's empty. That is, you can't return None and that's why the Rust API
|
|
// expects Local<Value> instead of Option<Local<Value>>.
|
|
unsafe {
|
|
v8__Isolate__SetPrepareStackTraceCallback(self, callback.map_fn_to())
|
|
};
|
|
}
|
|
|
|
/// Set the PromiseHook callback for various promise lifecycle
|
|
/// events.
|
|
#[inline(always)]
|
|
pub fn set_promise_hook(&mut self, hook: PromiseHook) {
|
|
unsafe { v8__Isolate__SetPromiseHook(self, hook) }
|
|
}
|
|
|
|
/// Set callback to notify about promise reject with no handler, or
|
|
/// revocation of such a previous notification once the handler is added.
|
|
#[inline(always)]
|
|
pub fn set_promise_reject_callback(
|
|
&mut self,
|
|
callback: PromiseRejectCallback,
|
|
) {
|
|
unsafe { v8__Isolate__SetPromiseRejectCallback(self, callback) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn set_wasm_async_resolve_promise_callback(
|
|
&mut self,
|
|
callback: WasmAsyncResolvePromiseCallback,
|
|
) {
|
|
unsafe { v8__Isolate__SetWasmAsyncResolvePromiseCallback(self, callback) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
/// This specifies the callback called by the upcoming importa.meta
|
|
/// language feature to retrieve host-defined meta data for a module.
|
|
pub fn set_host_initialize_import_meta_object_callback(
|
|
&mut self,
|
|
callback: HostInitializeImportMetaObjectCallback,
|
|
) {
|
|
unsafe {
|
|
v8__Isolate__SetHostInitializeImportMetaObjectCallback(self, callback)
|
|
}
|
|
}
|
|
|
|
/// This specifies the callback called by the upcoming dynamic
|
|
/// import() language feature to load modules.
|
|
#[inline(always)]
|
|
pub fn set_host_import_module_dynamically_callback(
|
|
&mut self,
|
|
callback: impl HostImportModuleDynamicallyCallback,
|
|
) {
|
|
unsafe {
|
|
v8__Isolate__SetHostImportModuleDynamicallyCallback(
|
|
self,
|
|
callback.to_c_fn(),
|
|
)
|
|
}
|
|
}
|
|
|
|
/// This specifies the callback called by the upcoming `ShadowRealm`
|
|
/// construction language feature to retrieve host created globals.
|
|
pub fn set_host_create_shadow_realm_context_callback(
|
|
&mut self,
|
|
callback: HostCreateShadowRealmContextCallback,
|
|
) {
|
|
#[inline]
|
|
extern "C" fn rust_shadow_realm_callback(
|
|
initiator_context: Local<Context>,
|
|
) -> *mut Context {
|
|
let mut scope = unsafe { CallbackScope::new(initiator_context) };
|
|
let callback = scope
|
|
.get_slot::<HostCreateShadowRealmContextCallback>()
|
|
.unwrap();
|
|
let context = callback(&mut scope);
|
|
context
|
|
.map(|l| l.as_non_null().as_ptr())
|
|
.unwrap_or_else(null_mut)
|
|
}
|
|
|
|
// Windows x64 ABI: MaybeLocal<Context> must be returned on the stack.
|
|
#[cfg(target_os = "windows")]
|
|
extern "C" fn rust_shadow_realm_callback_windows(
|
|
rv: *mut *mut Context,
|
|
initiator_context: Local<Context>,
|
|
) -> *mut *mut Context {
|
|
let ret = rust_shadow_realm_callback(initiator_context);
|
|
unsafe {
|
|
rv.write(ret);
|
|
}
|
|
rv
|
|
}
|
|
|
|
let slot_didnt_exist_before = self.set_slot(callback);
|
|
if slot_didnt_exist_before {
|
|
unsafe {
|
|
#[cfg(target_os = "windows")]
|
|
v8__Isolate__SetHostCreateShadowRealmContextCallback(
|
|
self,
|
|
rust_shadow_realm_callback_windows,
|
|
);
|
|
#[cfg(not(target_os = "windows"))]
|
|
v8__Isolate__SetHostCreateShadowRealmContextCallback(
|
|
self,
|
|
rust_shadow_realm_callback,
|
|
);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// 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.
|
|
#[allow(clippy::not_unsafe_ptr_arg_deref)] // False positive.
|
|
#[inline(always)]
|
|
pub fn add_gc_prologue_callback(
|
|
&mut self,
|
|
callback: GcCallbackWithData,
|
|
data: *mut c_void,
|
|
gc_type_filter: GCType,
|
|
) {
|
|
unsafe {
|
|
v8__Isolate__AddGCPrologueCallback(self, callback, data, gc_type_filter)
|
|
}
|
|
}
|
|
|
|
/// This function removes callback which was installed by
|
|
/// AddGCPrologueCallback function.
|
|
#[allow(clippy::not_unsafe_ptr_arg_deref)] // False positive.
|
|
#[inline(always)]
|
|
pub fn remove_gc_prologue_callback(
|
|
&mut self,
|
|
callback: GcCallbackWithData,
|
|
data: *mut c_void,
|
|
) {
|
|
unsafe { v8__Isolate__RemoveGCPrologueCallback(self, callback, data) }
|
|
}
|
|
|
|
/// 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.
|
|
#[allow(clippy::not_unsafe_ptr_arg_deref)] // False positive.
|
|
#[inline(always)]
|
|
pub fn add_near_heap_limit_callback(
|
|
&mut self,
|
|
callback: NearHeapLimitCallback,
|
|
data: *mut c_void,
|
|
) {
|
|
unsafe { v8__Isolate__AddNearHeapLimitCallback(self, callback, 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.
|
|
#[inline(always)]
|
|
pub fn remove_near_heap_limit_callback(
|
|
&mut self,
|
|
callback: NearHeapLimitCallback,
|
|
heap_limit: usize,
|
|
) {
|
|
unsafe {
|
|
v8__Isolate__RemoveNearHeapLimitCallback(self, callback, heap_limit)
|
|
};
|
|
}
|
|
|
|
/// 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.
|
|
#[inline(always)]
|
|
pub fn adjust_amount_of_external_allocated_memory(
|
|
&mut self,
|
|
change_in_bytes: i64,
|
|
) -> i64 {
|
|
unsafe {
|
|
v8__Isolate__AdjustAmountOfExternalAllocatedMemory(self, change_in_bytes)
|
|
}
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn set_oom_error_handler(&mut self, callback: OomErrorCallback) {
|
|
unsafe { v8__Isolate__SetOOMErrorHandler(self, callback) };
|
|
}
|
|
|
|
/// Returns the policy controlling how Microtasks are invoked.
|
|
#[inline(always)]
|
|
pub fn get_microtasks_policy(&self) -> MicrotasksPolicy {
|
|
unsafe { v8__Isolate__GetMicrotasksPolicy(self) }
|
|
}
|
|
|
|
/// Returns the policy controlling how Microtasks are invoked.
|
|
#[inline(always)]
|
|
pub fn set_microtasks_policy(&mut self, policy: MicrotasksPolicy) {
|
|
unsafe { v8__Isolate__SetMicrotasksPolicy(self, policy) }
|
|
}
|
|
|
|
/// 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.
|
|
#[inline(always)]
|
|
pub fn perform_microtask_checkpoint(&mut self) {
|
|
unsafe { v8__Isolate__PerformMicrotaskCheckpoint(self) }
|
|
}
|
|
|
|
/// An alias for PerformMicrotaskCheckpoint.
|
|
#[deprecated(note = "Use Isolate::perform_microtask_checkpoint() instead")]
|
|
pub fn run_microtasks(&mut self) {
|
|
self.perform_microtask_checkpoint()
|
|
}
|
|
|
|
/// Enqueues the callback to the default MicrotaskQueue
|
|
#[inline(always)]
|
|
pub fn enqueue_microtask(&mut self, microtask: Local<Function>) {
|
|
unsafe { v8__Isolate__EnqueueMicrotask(self, &*microtask) }
|
|
}
|
|
|
|
/// 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.
|
|
#[inline(always)]
|
|
pub fn set_allow_atomics_wait(&mut self, allow: bool) {
|
|
unsafe { v8__Isolate__SetAllowAtomicsWait(self, allow) }
|
|
}
|
|
|
|
/// Embedder injection point for `WebAssembly.compileStreaming(source)`.
|
|
/// The expectation is that the embedder sets it at most once.
|
|
///
|
|
/// The callback receives the source argument (string, Promise, etc.)
|
|
/// and an instance of [WasmStreaming]. The [WasmStreaming] instance
|
|
/// can outlive the callback and is used to feed data chunks to V8
|
|
/// asynchronously.
|
|
#[inline(always)]
|
|
pub fn set_wasm_streaming_callback<F>(&mut self, _: F)
|
|
where
|
|
F: UnitType + Fn(&mut HandleScope, Local<Value>, WasmStreaming),
|
|
{
|
|
unsafe { v8__Isolate__SetWasmStreamingCallback(self, trampoline::<F>()) }
|
|
}
|
|
|
|
/// Returns true if there is ongoing background work within V8 that will
|
|
/// eventually post a foreground task, like asynchronous WebAssembly
|
|
/// compilation.
|
|
#[inline(always)]
|
|
pub fn has_pending_background_tasks(&self) -> bool {
|
|
unsafe { v8__Isolate__HasPendingBackgroundTasks(self) }
|
|
}
|
|
|
|
/// 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.
|
|
#[inline(always)]
|
|
pub fn request_garbage_collection_for_testing(
|
|
&mut self,
|
|
r#type: GarbageCollectionType,
|
|
) {
|
|
unsafe {
|
|
v8__Isolate__RequestGarbageCollectionForTesting(
|
|
self,
|
|
match r#type {
|
|
GarbageCollectionType::Full => 0,
|
|
GarbageCollectionType::Minor => 1,
|
|
},
|
|
)
|
|
}
|
|
}
|
|
|
|
unsafe fn clear_scope_and_annex(&mut self) {
|
|
// Drop the scope stack.
|
|
ScopeData::drop_root(self);
|
|
|
|
// Set the `isolate` pointer inside the annex struct to null, so any
|
|
// IsolateHandle that outlives the isolate will know that it can't call
|
|
// methods on the isolate.
|
|
let annex = self.get_annex_mut();
|
|
{
|
|
let _lock = annex.isolate_mutex.lock().unwrap();
|
|
annex.isolate = null_mut();
|
|
}
|
|
|
|
// Clear slots and drop owned objects that were taken out of `CreateParams`.
|
|
annex.create_param_allocations = Box::new(());
|
|
annex.slots.clear();
|
|
|
|
// Run through any remaining guaranteed finalizers.
|
|
for finalizer in annex.finalizer_map.drain() {
|
|
if let FinalizerCallback::Guaranteed(callback) = finalizer {
|
|
callback();
|
|
}
|
|
}
|
|
|
|
// Subtract one from the Arc<IsolateAnnex> reference count.
|
|
Arc::from_raw(annex);
|
|
self.set_data(0, null_mut());
|
|
}
|
|
|
|
/// Disposes the isolate. The isolate must not be entered by any
|
|
/// thread to be disposable.
|
|
unsafe fn dispose(&mut self) {
|
|
// No test case in rusty_v8 show this, but there have been situations in
|
|
// deno where dropping Annex before the states causes a segfault.
|
|
v8__Isolate__Dispose(self)
|
|
}
|
|
|
|
/// Take a heap snapshot. The callback is invoked one or more times
|
|
/// with byte slices containing the snapshot serialized as JSON.
|
|
/// It's the callback's responsibility to reassemble them into
|
|
/// a single document, e.g., by writing them to a file.
|
|
/// Note that Chrome DevTools refuses to load snapshots without
|
|
/// a .heapsnapshot suffix.
|
|
pub fn take_heap_snapshot<F>(&mut self, mut callback: F)
|
|
where
|
|
F: FnMut(&[u8]) -> bool,
|
|
{
|
|
extern "C" fn trampoline<F>(
|
|
arg: *mut c_void,
|
|
data: *const u8,
|
|
size: usize,
|
|
) -> bool
|
|
where
|
|
F: FnMut(&[u8]) -> bool,
|
|
{
|
|
let p = arg as *mut F;
|
|
let callback = unsafe { &mut *p };
|
|
let slice = unsafe { std::slice::from_raw_parts(data, size) };
|
|
callback(slice)
|
|
}
|
|
|
|
let arg = &mut callback as *mut F as *mut c_void;
|
|
unsafe { v8__HeapProfiler__TakeHeapSnapshot(self, trampoline::<F>, arg) }
|
|
}
|
|
|
|
/// Set the default context to be included in the snapshot blob.
|
|
/// The snapshot will not contain the global proxy, and we expect one or a
|
|
/// global object template to create one, to be provided upon deserialization.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if the isolate was not created using [`Isolate::snapshot_creator`]
|
|
#[inline(always)]
|
|
pub fn set_default_context(&mut self, context: Local<Context>) {
|
|
let snapshot_creator = self
|
|
.get_annex_mut()
|
|
.maybe_snapshot_creator
|
|
.as_mut()
|
|
.unwrap();
|
|
snapshot_creator.set_default_context(context);
|
|
}
|
|
|
|
/// Add additional context to be included in the snapshot blob.
|
|
/// The snapshot will include the global proxy.
|
|
///
|
|
/// Returns the index of the context in the snapshot blob.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if the isolate was not created using [`Isolate::snapshot_creator`]
|
|
#[inline(always)]
|
|
pub fn add_context(&mut self, context: Local<Context>) -> usize {
|
|
let snapshot_creator = self
|
|
.get_annex_mut()
|
|
.maybe_snapshot_creator
|
|
.as_mut()
|
|
.unwrap();
|
|
snapshot_creator.add_context(context)
|
|
}
|
|
|
|
/// Attach arbitrary `v8::Data` to the isolate snapshot, which can be
|
|
/// retrieved via `HandleScope::get_context_data_from_snapshot_once()` after
|
|
/// deserialization. This data does not survive when a new snapshot is created
|
|
/// from an existing snapshot.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if the isolate was not created using [`Isolate::snapshot_creator`]
|
|
#[inline(always)]
|
|
pub fn add_isolate_data<T>(&mut self, data: Local<T>) -> usize
|
|
where
|
|
for<'l> Local<'l, T>: Into<Local<'l, Data>>,
|
|
{
|
|
let snapshot_creator = self
|
|
.get_annex_mut()
|
|
.maybe_snapshot_creator
|
|
.as_mut()
|
|
.unwrap();
|
|
snapshot_creator.add_isolate_data(data)
|
|
}
|
|
|
|
/// Attach arbitrary `v8::Data` to the context snapshot, which can be
|
|
/// retrieved via `HandleScope::get_context_data_from_snapshot_once()` after
|
|
/// deserialization. This data does not survive when a new snapshot is
|
|
/// created from an existing snapshot.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if the isolate was not created using [`Isolate::snapshot_creator`]
|
|
#[inline(always)]
|
|
pub fn add_context_data<T>(
|
|
&mut self,
|
|
context: Local<Context>,
|
|
data: Local<T>,
|
|
) -> usize
|
|
where
|
|
for<'l> Local<'l, T>: Into<Local<'l, Data>>,
|
|
{
|
|
let snapshot_creator = self
|
|
.get_annex_mut()
|
|
.maybe_snapshot_creator
|
|
.as_mut()
|
|
.unwrap();
|
|
snapshot_creator.add_context_data(context, data)
|
|
}
|
|
}
|
|
|
|
pub(crate) struct IsolateAnnex {
|
|
create_param_allocations: Box<dyn Any>,
|
|
slots: HashMap<TypeId, RawSlot, BuildTypeIdHasher>,
|
|
finalizer_map: FinalizerMap,
|
|
maybe_snapshot_creator: Option<SnapshotCreator>,
|
|
// The `isolate` and `isolate_mutex` fields are there so an `IsolateHandle`
|
|
// (which may outlive the isolate itself) can determine whether the isolate
|
|
// is still alive, and if so, get a reference to it. Safety rules:
|
|
// - The 'main thread' must lock the mutex and reset `isolate` to null just
|
|
// before the isolate is disposed.
|
|
// - Any other thread must lock the mutex while it's reading/using the
|
|
// `isolate` pointer.
|
|
isolate: *mut Isolate,
|
|
isolate_mutex: Mutex<()>,
|
|
}
|
|
|
|
impl IsolateAnnex {
|
|
fn new(
|
|
isolate: &mut Isolate,
|
|
create_param_allocations: Box<dyn Any>,
|
|
) -> Self {
|
|
Self {
|
|
create_param_allocations,
|
|
slots: HashMap::default(),
|
|
finalizer_map: FinalizerMap::default(),
|
|
maybe_snapshot_creator: None,
|
|
isolate,
|
|
isolate_mutex: Mutex::new(()),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Debug for IsolateAnnex {
|
|
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
|
|
f.debug_struct("IsolateAnnex")
|
|
.field("isolate", &self.isolate)
|
|
.field("isolate_mutex", &self.isolate_mutex)
|
|
.finish()
|
|
}
|
|
}
|
|
|
|
/// IsolateHandle is a thread-safe reference to an Isolate. It's main use is to
|
|
/// terminate execution of a running isolate from another thread.
|
|
///
|
|
/// It is created with Isolate::thread_safe_handle().
|
|
///
|
|
/// IsolateHandle is Cloneable, Send, and Sync.
|
|
#[derive(Clone, Debug)]
|
|
pub struct IsolateHandle(Arc<IsolateAnnex>);
|
|
|
|
unsafe impl Send for IsolateHandle {}
|
|
unsafe impl Sync for IsolateHandle {}
|
|
|
|
impl IsolateHandle {
|
|
// This function is marked unsafe because it must be called only with either
|
|
// IsolateAnnex::mutex locked, or from the main thread associated with the V8
|
|
// isolate.
|
|
pub(crate) unsafe fn get_isolate_ptr(&self) -> *mut Isolate {
|
|
self.0.isolate
|
|
}
|
|
|
|
#[inline(always)]
|
|
fn new(isolate: &Isolate) -> Self {
|
|
Self(isolate.get_annex_arc())
|
|
}
|
|
|
|
/// 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.
|
|
///
|
|
/// Returns false if Isolate was already destroyed.
|
|
#[inline(always)]
|
|
pub fn terminate_execution(&self) -> bool {
|
|
let _lock = self.0.isolate_mutex.lock().unwrap();
|
|
if self.0.isolate.is_null() {
|
|
false
|
|
} else {
|
|
unsafe { v8__Isolate__TerminateExecution(self.0.isolate) };
|
|
true
|
|
}
|
|
}
|
|
|
|
/// 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.
|
|
///
|
|
/// Returns false if Isolate was already destroyed.
|
|
#[inline(always)]
|
|
pub fn cancel_terminate_execution(&self) -> bool {
|
|
let _lock = self.0.isolate_mutex.lock().unwrap();
|
|
if self.0.isolate.is_null() {
|
|
false
|
|
} else {
|
|
unsafe { v8__Isolate__CancelTerminateExecution(self.0.isolate) };
|
|
true
|
|
}
|
|
}
|
|
|
|
/// 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.
|
|
///
|
|
/// Returns false if Isolate was already destroyed.
|
|
#[inline(always)]
|
|
pub fn is_execution_terminating(&self) -> bool {
|
|
let _lock = self.0.isolate_mutex.lock().unwrap();
|
|
if self.0.isolate.is_null() {
|
|
false
|
|
} else {
|
|
unsafe { v8__Isolate__IsExecutionTerminating(self.0.isolate) }
|
|
}
|
|
}
|
|
|
|
/// 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.
|
|
///
|
|
/// Returns false if Isolate was already destroyed.
|
|
// Clippy warns that this method is dereferencing a raw pointer, but it is
|
|
// not: https://github.com/rust-lang/rust-clippy/issues/3045
|
|
#[allow(clippy::not_unsafe_ptr_arg_deref)]
|
|
#[inline(always)]
|
|
pub fn request_interrupt(
|
|
&self,
|
|
callback: InterruptCallback,
|
|
data: *mut c_void,
|
|
) -> bool {
|
|
let _lock = self.0.isolate_mutex.lock().unwrap();
|
|
if self.0.isolate.is_null() {
|
|
false
|
|
} else {
|
|
unsafe { v8__Isolate__RequestInterrupt(self.0.isolate, callback, data) };
|
|
true
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Same as Isolate but gets disposed when it goes out of scope.
|
|
#[derive(Debug)]
|
|
pub struct OwnedIsolate {
|
|
cxx_isolate: NonNull<Isolate>,
|
|
}
|
|
|
|
impl OwnedIsolate {
|
|
pub(crate) fn new(cxx_isolate: *mut Isolate) -> Self {
|
|
let cxx_isolate = NonNull::new(cxx_isolate).unwrap();
|
|
Self { cxx_isolate }
|
|
}
|
|
}
|
|
|
|
impl Drop for OwnedIsolate {
|
|
fn drop(&mut self) {
|
|
unsafe {
|
|
let snapshot_creator = self.get_annex_mut().maybe_snapshot_creator.take();
|
|
assert!(
|
|
snapshot_creator.is_none(),
|
|
"If isolate was created using v8::Isolate::snapshot_creator, you should use v8::OwnedIsolate::create_blob before dropping an isolate."
|
|
);
|
|
self.exit();
|
|
self.cxx_isolate.as_mut().clear_scope_and_annex();
|
|
self.cxx_isolate.as_mut().dispose();
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Deref for OwnedIsolate {
|
|
type Target = Isolate;
|
|
fn deref(&self) -> &Self::Target {
|
|
unsafe { self.cxx_isolate.as_ref() }
|
|
}
|
|
}
|
|
|
|
impl DerefMut for OwnedIsolate {
|
|
fn deref_mut(&mut self) -> &mut Self::Target {
|
|
unsafe { self.cxx_isolate.as_mut() }
|
|
}
|
|
}
|
|
|
|
impl AsMut<Isolate> for OwnedIsolate {
|
|
fn as_mut(&mut self) -> &mut Isolate {
|
|
self
|
|
}
|
|
}
|
|
|
|
impl AsMut<Isolate> for Isolate {
|
|
fn as_mut(&mut self) -> &mut Isolate {
|
|
self
|
|
}
|
|
}
|
|
|
|
impl OwnedIsolate {
|
|
/// Creates a snapshot data blob.
|
|
/// This must not be called from within a handle scope.
|
|
///
|
|
/// # Panics
|
|
///
|
|
/// Panics if the isolate was not created using [`Isolate::snapshot_creator`]
|
|
#[inline(always)]
|
|
pub fn create_blob(
|
|
mut self,
|
|
function_code_handling: FunctionCodeHandling,
|
|
) -> Option<StartupData> {
|
|
let mut snapshot_creator =
|
|
self.get_annex_mut().maybe_snapshot_creator.take().unwrap();
|
|
unsafe { self.cxx_isolate.as_mut().clear_scope_and_annex() };
|
|
// The isolate is owned by the snapshot creator; we need to forget it
|
|
// here as the snapshot creator will drop it when running the destructor.
|
|
std::mem::forget(self);
|
|
snapshot_creator.create_blob(function_code_handling)
|
|
}
|
|
}
|
|
|
|
impl HeapStatistics {
|
|
#[inline(always)]
|
|
pub fn total_heap_size(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__total_heap_size(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn total_heap_size_executable(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__total_heap_size_executable(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn total_physical_size(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__total_physical_size(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn total_available_size(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__total_available_size(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn total_global_handles_size(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__total_global_handles_size(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn used_global_handles_size(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__used_global_handles_size(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn used_heap_size(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__used_heap_size(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn heap_size_limit(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__heap_size_limit(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn malloced_memory(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__malloced_memory(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn external_memory(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__external_memory(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn peak_malloced_memory(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__peak_malloced_memory(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn number_of_native_contexts(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__number_of_native_contexts(self) }
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub fn number_of_detached_contexts(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__number_of_detached_contexts(self) }
|
|
}
|
|
|
|
/// Returns a 0/1 boolean, which signifies whether the V8 overwrite heap
|
|
/// garbage with a bit pattern.
|
|
#[inline(always)]
|
|
pub fn does_zap_garbage(&self) -> usize {
|
|
unsafe { v8__HeapStatistics__does_zap_garbage(self) }
|
|
}
|
|
}
|
|
|
|
impl Default for HeapStatistics {
|
|
fn default() -> Self {
|
|
let mut s = MaybeUninit::<Self>::uninit();
|
|
unsafe {
|
|
v8__HeapStatistics__CONSTRUCT(&mut s);
|
|
s.assume_init()
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'s, F> MapFnFrom<F> for PrepareStackTraceCallback<'s>
|
|
where
|
|
F: UnitType
|
|
+ Fn(
|
|
&mut HandleScope<'s>,
|
|
Local<'s, Value>,
|
|
Local<'s, Array>,
|
|
) -> Local<'s, Value>,
|
|
{
|
|
// Windows x64 ABI: MaybeLocal<Value> returned on the stack.
|
|
#[cfg(target_os = "windows")]
|
|
fn mapping() -> Self {
|
|
let f = |ret_ptr, context, error, sites| {
|
|
let mut scope: CallbackScope = unsafe { CallbackScope::new(context) };
|
|
let r = (F::get())(&mut scope, error, sites);
|
|
unsafe { std::ptr::write(ret_ptr, &*r as *const _) };
|
|
ret_ptr
|
|
};
|
|
f.to_c_fn()
|
|
}
|
|
|
|
// System V ABI
|
|
#[cfg(not(target_os = "windows"))]
|
|
fn mapping() -> Self {
|
|
let f = |context, error, sites| {
|
|
let mut scope: CallbackScope = unsafe { CallbackScope::new(context) };
|
|
let r = (F::get())(&mut scope, error, sites);
|
|
PrepareStackTraceCallbackRet(&*r as *const _)
|
|
};
|
|
f.to_c_fn()
|
|
}
|
|
}
|
|
|
|
/// A special hasher that is optimized for hashing `std::any::TypeId` values.
|
|
/// `TypeId` values are actually 64-bit values which themselves come out of some
|
|
/// hash function, so it's unnecessary to shuffle their bits any further.
|
|
#[derive(Clone, Default)]
|
|
pub(crate) struct TypeIdHasher {
|
|
state: Option<u64>,
|
|
}
|
|
|
|
impl Hasher for TypeIdHasher {
|
|
fn write(&mut self, _bytes: &[u8]) {
|
|
panic!("TypeIdHasher::write() called unexpectedly");
|
|
}
|
|
|
|
#[inline]
|
|
fn write_u64(&mut self, value: u64) {
|
|
let prev_state = self.state.replace(value);
|
|
debug_assert_eq!(prev_state, None);
|
|
}
|
|
|
|
#[inline]
|
|
fn finish(&self) -> u64 {
|
|
self.state.unwrap()
|
|
}
|
|
}
|
|
|
|
/// Factory for instances of `TypeIdHasher`. This is the type that one would
|
|
/// pass to the constructor of some map/set type in order to make it use
|
|
/// `TypeIdHasher` instead of the default hasher implementation.
|
|
#[derive(Copy, Clone, Default)]
|
|
pub(crate) struct BuildTypeIdHasher;
|
|
|
|
impl BuildHasher for BuildTypeIdHasher {
|
|
type Hasher = TypeIdHasher;
|
|
|
|
#[inline]
|
|
fn build_hasher(&self) -> Self::Hasher {
|
|
Default::default()
|
|
}
|
|
}
|
|
|
|
const _: () = {
|
|
assert!(size_of::<TypeId>() == size_of::<u64>());
|
|
assert!(align_of::<TypeId>() == align_of::<u64>());
|
|
};
|
|
|
|
pub(crate) struct RawSlot {
|
|
data: RawSlotData,
|
|
dtor: Option<RawSlotDtor>,
|
|
}
|
|
|
|
type RawSlotData = MaybeUninit<usize>;
|
|
type RawSlotDtor = unsafe fn(&mut RawSlotData) -> ();
|
|
|
|
impl RawSlot {
|
|
#[inline]
|
|
pub fn new<T: 'static>(value: T) -> Self {
|
|
if Self::needs_box::<T>() {
|
|
Self::new_internal(Box::new(value))
|
|
} else {
|
|
Self::new_internal(value)
|
|
}
|
|
}
|
|
|
|
// SAFETY: a valid value of type `T` must haven been stored in the slot
|
|
// earlier. There is no verification that the type param provided by the
|
|
// caller is correct.
|
|
#[inline]
|
|
pub unsafe fn borrow<T: 'static>(&self) -> &T {
|
|
if Self::needs_box::<T>() {
|
|
&*(self.data.as_ptr() as *const Box<T>)
|
|
} else {
|
|
&*(self.data.as_ptr() as *const T)
|
|
}
|
|
}
|
|
|
|
// Safety: see [`RawSlot::borrow`].
|
|
#[inline]
|
|
pub unsafe fn borrow_mut<T: 'static>(&mut self) -> &mut T {
|
|
if Self::needs_box::<T>() {
|
|
&mut *(self.data.as_mut_ptr() as *mut Box<T>)
|
|
} else {
|
|
&mut *(self.data.as_mut_ptr() as *mut T)
|
|
}
|
|
}
|
|
|
|
// Safety: see [`RawSlot::borrow`].
|
|
#[inline]
|
|
pub unsafe fn into_inner<T: 'static>(self) -> T {
|
|
let value = if Self::needs_box::<T>() {
|
|
*std::ptr::read(self.data.as_ptr() as *mut Box<T>)
|
|
} else {
|
|
std::ptr::read(self.data.as_ptr() as *mut T)
|
|
};
|
|
forget(self);
|
|
value
|
|
}
|
|
|
|
const fn needs_box<T: 'static>() -> bool {
|
|
size_of::<T>() > size_of::<RawSlotData>()
|
|
|| align_of::<T>() > align_of::<RawSlotData>()
|
|
}
|
|
|
|
#[inline]
|
|
fn new_internal<B: 'static>(value: B) -> Self {
|
|
assert!(!Self::needs_box::<B>());
|
|
let mut self_ = Self {
|
|
data: RawSlotData::zeroed(),
|
|
dtor: None,
|
|
};
|
|
unsafe {
|
|
ptr::write(self_.data.as_mut_ptr() as *mut B, value);
|
|
}
|
|
if needs_drop::<B>() {
|
|
self_.dtor.replace(Self::drop_internal::<B>);
|
|
};
|
|
self_
|
|
}
|
|
|
|
// SAFETY: a valid value of type `T` or `Box<T>` must be stored in the slot.
|
|
unsafe fn drop_internal<B: 'static>(data: &mut RawSlotData) {
|
|
assert!(!Self::needs_box::<B>());
|
|
drop_in_place(data.as_mut_ptr() as *mut B);
|
|
}
|
|
}
|
|
|
|
impl Drop for RawSlot {
|
|
fn drop(&mut self) {
|
|
if let Some(dtor) = self.dtor {
|
|
unsafe { dtor(&mut self.data) };
|
|
}
|
|
}
|
|
}
|