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denoland-deno/core/isolate.rs

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// Copyright 2018 the Deno authors. All rights reserved. MIT license.
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// Do not add any dependency to modules.rs!
// modules.rs is complex and should remain decoupled from isolate.rs to keep the
// Isolate struct from becoming too bloating for users who do not need
// asynchronous module loading.
use crate::any_error::ErrBox;
use crate::js_errors::CoreJSError;
use crate::js_errors::V8Exception;
use crate::libdeno;
use crate::libdeno::deno_buf;
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use crate::libdeno::deno_dyn_import_id;
use crate::libdeno::deno_mod;
use crate::libdeno::deno_pinned_buf;
use crate::libdeno::PinnedBuf;
use crate::libdeno::Snapshot1;
use crate::libdeno::Snapshot2;
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use crate::ops::*;
use crate::shared_queue::SharedQueue;
use crate::shared_queue::RECOMMENDED_SIZE;
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use futures::future::FutureExt;
use futures::future::TryFutureExt;
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use futures::stream::FuturesUnordered;
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use futures::stream::IntoStream;
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use futures::stream::Stream;
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use futures::stream::StreamExt;
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use futures::stream::StreamFuture;
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use futures::stream::TryStream;
use futures::stream::TryStreamExt;
use futures::task::AtomicWaker;
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use libc::c_char;
use libc::c_void;
use std::ffi::CStr;
use std::ffi::CString;
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use std::fmt;
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use std::future::Future;
use std::pin::Pin;
use std::ptr::null;
use std::sync::{Arc, Mutex, Once};
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use std::task::Context;
use std::task::Poll;
/// Stores a script used to initalize a Isolate
pub struct Script<'a> {
pub source: &'a str,
pub filename: &'a str,
}
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/// Represent result of fetching the source code of a module. Found module URL
/// might be different from specified URL used for loading due to redirections
/// (like HTTP 303). E.G. Both https://example.com/a.ts and
/// https://example.com/b.ts may point to https://example.com/c.ts
/// By keeping track of specified and found URL we can alias modules and avoid
/// recompiling the same code 3 times.
#[derive(Debug, Eq, PartialEq)]
pub struct SourceCodeInfo {
pub code: String,
pub module_url_specified: String,
pub module_url_found: String,
}
#[derive(Debug, Eq, PartialEq)]
pub enum RecursiveLoadEvent {
Fetch(SourceCodeInfo),
Instantiate(deno_mod),
}
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pub trait ImportStream: TryStream {
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fn register(
&mut self,
source_code_info: SourceCodeInfo,
isolate: &mut Isolate,
) -> Result<(), ErrBox>;
}
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type DynImportStream = Box<
dyn ImportStream<
Ok = RecursiveLoadEvent,
Error = ErrBox,
Item = Result<RecursiveLoadEvent, ErrBox>,
> + Send
+ Unpin,
>;
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type DynImportFn = dyn Fn(deno_dyn_import_id, &str, &str) -> DynImportStream;
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/// Wraps DynImportStream to include the deno_dyn_import_id, so that it doesn't
/// need to be exposed.
#[derive(Debug)]
struct DynImport {
pub id: deno_dyn_import_id,
pub inner: DynImportStream,
}
impl fmt::Debug for DynImportStream {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "DynImportStream(..)")
}
}
impl Stream for DynImport {
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type Item = Result<
(deno_dyn_import_id, RecursiveLoadEvent),
(deno_dyn_import_id, ErrBox),
>;
fn poll_next(
self: Pin<&mut Self>,
cx: &mut Context,
) -> Poll<Option<Self::Item>> {
let self_inner = self.get_mut();
match self_inner.inner.try_poll_next_unpin(cx) {
Poll::Ready(Some(Ok(event))) => {
Poll::Ready(Some(Ok((self_inner.id, event))))
}
Poll::Ready(None) => unreachable!(),
Poll::Ready(Some(Err(e))) => Poll::Ready(Some(Err((self_inner.id, e)))),
Poll::Pending => Poll::Pending,
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}
}
}
impl ImportStream for DynImport {
fn register(
&mut self,
source_code_info: SourceCodeInfo,
isolate: &mut Isolate,
) -> Result<(), ErrBox> {
self.inner.register(source_code_info, isolate)
}
}
// TODO(ry) It's ugly that we have both Script and OwnedScript. Ideally we
// wouldn't expose such twiddly complexity.
struct OwnedScript {
pub source: String,
pub filename: String,
}
impl From<Script<'_>> for OwnedScript {
fn from(s: Script) -> OwnedScript {
OwnedScript {
source: s.source.to_string(),
filename: s.filename.to_string(),
}
}
}
/// Represents data used to initialize isolate at startup
/// either a binary snapshot or a javascript source file
/// in the form of the StartupScript struct.
pub enum StartupData<'a> {
Script(Script<'a>),
Snapshot(&'a [u8]),
LibdenoSnapshot(Snapshot1<'a>),
None,
}
type JSErrorCreateFn = dyn Fn(V8Exception) -> ErrBox;
/// A single execution context of JavaScript. Corresponds roughly to the "Web
/// Worker" concept in the DOM. An Isolate is a Future that can be used with
/// Tokio. The Isolate future complete when there is an error or when all
/// pending ops have completed.
///
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/// Ops are created in JavaScript by calling Deno.core.dispatch(), and in Rust
/// by implementing dispatcher function that takes control buffer and optional zero copy buffer
/// as arguments. An async Op corresponds exactly to a Promise in JavaScript.
pub struct Isolate {
libdeno_isolate: *const libdeno::isolate,
shared_libdeno_isolate: Arc<Mutex<Option<*const libdeno::isolate>>>,
dyn_import: Option<Arc<DynImportFn>>,
js_error_create: Arc<JSErrorCreateFn>,
needs_init: bool,
shared: SharedQueue,
pending_ops: FuturesUnordered<PendingOpFuture>,
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pending_dyn_imports: FuturesUnordered<StreamFuture<IntoStream<DynImport>>>,
have_unpolled_ops: bool,
startup_script: Option<OwnedScript>,
pub op_registry: Arc<OpRegistry>,
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waker: AtomicWaker,
}
unsafe impl Send for Isolate {}
impl Drop for Isolate {
fn drop(&mut self) {
// remove shared_libdeno_isolate reference
*self.shared_libdeno_isolate.lock().unwrap() = None;
unsafe { libdeno::deno_delete(self.libdeno_isolate) }
}
}
static DENO_INIT: Once = Once::new();
impl Isolate {
/// startup_data defines the snapshot or script used at startup to initialize
/// the isolate.
pub fn new(startup_data: StartupData, will_snapshot: bool) -> Self {
DENO_INIT.call_once(|| {
unsafe { libdeno::deno_init() };
});
let shared = SharedQueue::new(RECOMMENDED_SIZE);
let needs_init = true;
let mut libdeno_config = libdeno::deno_config {
will_snapshot: will_snapshot.into(),
load_snapshot: Snapshot2::empty(),
shared: shared.as_deno_buf(),
recv_cb: Self::pre_dispatch,
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dyn_import_cb: Self::dyn_import,
};
let mut startup_script: Option<OwnedScript> = None;
// Separate into Option values for each startup type
match startup_data {
StartupData::Script(d) => {
startup_script = Some(d.into());
}
StartupData::Snapshot(d) => {
libdeno_config.load_snapshot = d.into();
}
StartupData::LibdenoSnapshot(d) => {
libdeno_config.load_snapshot = d;
}
StartupData::None => {}
};
let libdeno_isolate = unsafe { libdeno::deno_new(libdeno_config) };
Self {
libdeno_isolate,
shared_libdeno_isolate: Arc::new(Mutex::new(Some(libdeno_isolate))),
dyn_import: None,
js_error_create: Arc::new(CoreJSError::from_v8_exception),
shared,
needs_init,
pending_ops: FuturesUnordered::new(),
have_unpolled_ops: false,
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pending_dyn_imports: FuturesUnordered::new(),
startup_script,
op_registry: Arc::new(OpRegistry::new()),
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waker: AtomicWaker::new(),
}
}
/// Defines the how Deno.core.dispatch() acts.
/// Called whenever Deno.core.dispatch() is called in JavaScript. zero_copy_buf
/// corresponds to the second argument of Deno.core.dispatch().
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///
/// Requires runtime to explicitly ask for op ids before using any of the ops.
pub fn register_op<F>(&self, name: &str, op: F) -> OpId
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where
F: Fn(&[u8], Option<PinnedBuf>) -> CoreOp + Send + Sync + 'static,
{
self.op_registry.register(name, op)
}
pub fn set_dyn_import<F>(&mut self, f: F)
where
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F: Fn(deno_dyn_import_id, &str, &str) -> DynImportStream
+ Send
+ Sync
+ 'static,
{
self.dyn_import = Some(Arc::new(f));
}
/// Allows a callback to be set whenever a V8 exception is made. This allows
/// the caller to wrap the V8Exception into an error. By default this callback
/// is set to CoreJSError::from_v8_exception.
pub fn set_js_error_create<F>(&mut self, f: F)
where
F: Fn(V8Exception) -> ErrBox + 'static,
{
self.js_error_create = Arc::new(f);
}
/// Get a thread safe handle on the isolate.
pub fn shared_isolate_handle(&mut self) -> IsolateHandle {
IsolateHandle {
shared_libdeno_isolate: self.shared_libdeno_isolate.clone(),
}
}
/// Executes a bit of built-in JavaScript to provide Deno.sharedQueue.
fn shared_init(&mut self) {
if self.needs_init {
self.needs_init = false;
js_check(
self.execute("shared_queue.js", include_str!("shared_queue.js")),
);
// Maybe execute the startup script.
if let Some(s) = self.startup_script.take() {
self.execute(&s.filename, &s.source).unwrap()
}
}
}
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extern "C" fn dyn_import(
user_data: *mut c_void,
specifier: *const c_char,
referrer: *const c_char,
id: deno_dyn_import_id,
) {
assert_ne!(user_data, std::ptr::null_mut());
let isolate = unsafe { Isolate::from_raw_ptr(user_data) };
let specifier = unsafe { CStr::from_ptr(specifier).to_str().unwrap() };
let referrer = unsafe { CStr::from_ptr(referrer).to_str().unwrap() };
debug!("dyn_import specifier {} referrer {} ", specifier, referrer);
if let Some(ref f) = isolate.dyn_import {
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let inner = f(id, specifier, referrer);
let stream = DynImport { inner, id };
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isolate.waker.wake();
isolate
.pending_dyn_imports
.push(stream.into_stream().into_future());
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} else {
panic!("dyn_import callback not set")
}
}
extern "C" fn pre_dispatch(
user_data: *mut c_void,
op_id: OpId,
control_buf: deno_buf,
zero_copy_buf: deno_pinned_buf,
) {
let isolate = unsafe { Isolate::from_raw_ptr(user_data) };
let maybe_op = isolate.op_registry.call(
op_id,
control_buf.as_ref(),
PinnedBuf::new(zero_copy_buf),
);
let op = match maybe_op {
Some(op) => op,
None => {
return isolate.throw_exception(&format!("Unknown op id: {}", op_id))
}
};
debug_assert_eq!(isolate.shared.size(), 0);
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match op {
Op::Sync(buf) => {
// For sync messages, we always return the response via Deno.core.send's
// return value. Sync messages ignore the op_id.
let op_id = 0;
isolate
.respond(Some((op_id, &buf)))
// Because this is a sync op, deno_respond() does not actually call
// into JavaScript. We should not get an error here.
.expect("unexpected error");
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}
Op::Async(fut) => {
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let fut2 = fut.map_ok(move |buf| (op_id, buf));
isolate.pending_ops.push(fut2.boxed());
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isolate.have_unpolled_ops = true;
}
}
}
#[inline]
unsafe fn from_raw_ptr<'a>(ptr: *const c_void) -> &'a mut Self {
let ptr = ptr as *mut _;
&mut *ptr
}
#[inline]
fn as_raw_ptr(&self) -> *const c_void {
self as *const _ as *const c_void
}
/// Executes traditional JavaScript code (traditional = not ES modules)
///
/// ErrBox can be downcast to a type that exposes additional information about
/// the V8 exception. By default this type is CoreJSError, however it may be a
/// different type if Isolate::set_js_error_create() has been used.
pub fn execute(
&mut self,
js_filename: &str,
js_source: &str,
) -> Result<(), ErrBox> {
self.shared_init();
let filename = CString::new(js_filename).unwrap();
let source = CString::new(js_source).unwrap();
unsafe {
libdeno::deno_execute(
self.libdeno_isolate,
self.as_raw_ptr(),
filename.as_ptr(),
source.as_ptr(),
)
};
self.check_last_exception()
}
fn check_last_exception(&self) -> Result<(), ErrBox> {
let ptr = unsafe { libdeno::deno_last_exception(self.libdeno_isolate) };
if ptr.is_null() {
Ok(())
} else {
let js_error_create = &*self.js_error_create;
let cstr = unsafe { CStr::from_ptr(ptr) };
let json_str = cstr.to_str().unwrap();
let v8_exception = V8Exception::from_json(json_str).unwrap();
let js_error = js_error_create(v8_exception);
Err(js_error)
}
}
fn check_promise_errors(&self) {
unsafe {
libdeno::deno_check_promise_errors(self.libdeno_isolate);
}
}
fn throw_exception(&mut self, exception_text: &str) {
let text = CString::new(exception_text).unwrap();
unsafe {
libdeno::deno_throw_exception(self.libdeno_isolate, text.as_ptr())
}
}
fn respond(
&mut self,
maybe_buf: Option<(OpId, &[u8])>,
) -> Result<(), ErrBox> {
let (op_id, buf) = match maybe_buf {
None => (0, deno_buf::empty()),
Some((op_id, r)) => (op_id, deno_buf::from(r)),
};
unsafe {
libdeno::deno_respond(self.libdeno_isolate, self.as_raw_ptr(), op_id, buf)
}
self.check_last_exception()
}
/// Low-level module creation.
pub fn mod_new(
&self,
main: bool,
name: &str,
source: &str,
) -> Result<deno_mod, ErrBox> {
let name_ = CString::new(name.to_string()).unwrap();
let name_ptr = name_.as_ptr() as *const libc::c_char;
let source_ = CString::new(source.to_string()).unwrap();
let source_ptr = source_.as_ptr() as *const libc::c_char;
let id = unsafe {
libdeno::deno_mod_new(self.libdeno_isolate, main, name_ptr, source_ptr)
};
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self.check_last_exception().map(|_| id)
}
pub fn mod_get_imports(&self, id: deno_mod) -> Vec<String> {
let len =
unsafe { libdeno::deno_mod_imports_len(self.libdeno_isolate, id) };
let mut out = Vec::new();
for i in 0..len {
let specifier_ptr =
unsafe { libdeno::deno_mod_imports_get(self.libdeno_isolate, id, i) };
let specifier_c: &CStr = unsafe { CStr::from_ptr(specifier_ptr) };
let specifier: &str = specifier_c.to_str().unwrap();
out.push(specifier.to_string());
}
out
}
/// Takes a snapshot. The isolate should have been created with will_snapshot
/// set to true.
///
/// ErrBox can be downcast to a type that exposes additional information about
/// the V8 exception. By default this type is CoreJSError, however it may be a
/// different type if Isolate::set_js_error_create() has been used.
pub fn snapshot(&self) -> Result<Snapshot1<'static>, ErrBox> {
let snapshot = unsafe { libdeno::deno_snapshot_new(self.libdeno_isolate) };
match self.check_last_exception() {
Ok(..) => Ok(snapshot),
Err(err) => {
assert_eq!(snapshot.data_ptr, null());
assert_eq!(snapshot.data_len, 0);
Err(err)
}
}
}
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fn dyn_import_done(
&self,
id: libdeno::deno_dyn_import_id,
result: Result<deno_mod, Option<String>>,
) -> Result<(), ErrBox> {
debug!("dyn_import_done {} {:?}", id, result);
let (mod_id, maybe_err_str) = match result {
Ok(mod_id) => (mod_id, None),
Err(None) => (0, None),
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Err(Some(err_str)) => (0, Some(CString::new(err_str).unwrap())),
};
let err_str_ptr = match maybe_err_str {
Some(ref err_str) => err_str.as_ptr(),
None => std::ptr::null(),
};
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unsafe {
libdeno::deno_dyn_import_done(
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self.libdeno_isolate,
self.as_raw_ptr(),
id,
mod_id,
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err_str_ptr,
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)
};
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self.check_last_exception()
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}
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fn poll_dyn_imports(&mut self, cx: &mut Context) -> Poll<Result<(), ErrBox>> {
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use RecursiveLoadEvent::*;
loop {
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match self.pending_dyn_imports.poll_next_unpin(cx) {
Poll::Pending | Poll::Ready(None) => {
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// There are no active dynamic import loaders, or none are ready.
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return Poll::Ready(Ok(()));
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}
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Poll::Ready(Some((
Some(Ok((dyn_import_id, Fetch(source_code_info)))),
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mut stream,
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))) => {
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// A module (not necessarily the one dynamically imported) has been
// fetched. Create and register it, and if successful, poll for the
// next recursive-load event related to this dynamic import.
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match stream.get_mut().register(source_code_info, self) {
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Ok(()) => self.pending_dyn_imports.push(stream.into_future()),
Err(err) => {
self.dyn_import_done(dyn_import_id, Err(Some(err.to_string())))?
}
}
}
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Poll::Ready(Some((
Some(Ok((dyn_import_id, Instantiate(module_id)))),
_,
))) => {
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// The top-level module from a dynamic import has been instantiated.
match self.mod_evaluate(module_id) {
Ok(()) => self.dyn_import_done(dyn_import_id, Ok(module_id))?,
Err(..) => self.dyn_import_done(dyn_import_id, Err(None))?,
}
}
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Poll::Ready(Some((Some(Err((dyn_import_id, err))), _))) => {
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// A non-javascript error occurred; this could be due to a an invalid
// module specifier, or a problem with the source map, or a failure
// to fetch the module source code.
self.dyn_import_done(dyn_import_id, Err(Some(err.to_string())))?
}
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Poll::Ready(Some((None, _))) => unreachable!(),
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}
}
}
}
/// Called during mod_instantiate() to resolve imports.
type ResolveFn<'a> = dyn FnMut(&str, deno_mod) -> deno_mod + 'a;
/// Used internally by Isolate::mod_instantiate to wrap ResolveFn and
/// encapsulate pointer casts.
struct ResolveContext<'a> {
resolve_fn: &'a mut ResolveFn<'a>,
}
impl<'a> ResolveContext<'a> {
#[inline]
fn as_raw_ptr(&mut self) -> *mut c_void {
self as *mut _ as *mut c_void
}
#[inline]
unsafe fn from_raw_ptr(ptr: *mut c_void) -> &'a mut Self {
&mut *(ptr as *mut _)
}
}
impl Isolate {
/// Instanciates a ES module
///
/// ErrBox can be downcast to a type that exposes additional information about
/// the V8 exception. By default this type is CoreJSError, however it may be a
/// different type if Isolate::set_js_error_create() has been used.
pub fn mod_instantiate(
&mut self,
id: deno_mod,
resolve_fn: &mut ResolveFn,
) -> Result<(), ErrBox> {
let libdeno_isolate = self.libdeno_isolate;
let mut ctx = ResolveContext { resolve_fn };
unsafe {
libdeno::deno_mod_instantiate(
libdeno_isolate,
ctx.as_raw_ptr(),
id,
Self::resolve_cb,
)
};
self.check_last_exception()
}
/// Called during mod_instantiate() only.
extern "C" fn resolve_cb(
user_data: *mut libc::c_void,
specifier_ptr: *const libc::c_char,
referrer: deno_mod,
) -> deno_mod {
let ResolveContext { resolve_fn } =
unsafe { ResolveContext::from_raw_ptr(user_data) };
let specifier_c: &CStr = unsafe { CStr::from_ptr(specifier_ptr) };
let specifier: &str = specifier_c.to_str().unwrap();
resolve_fn(specifier, referrer)
}
/// Evaluates an already instantiated ES module.
///
/// ErrBox can be downcast to a type that exposes additional information about
/// the V8 exception. By default this type is CoreJSError, however it may be a
/// different type if Isolate::set_js_error_create() has been used.
pub fn mod_evaluate(&mut self, id: deno_mod) -> Result<(), ErrBox> {
self.shared_init();
unsafe {
libdeno::deno_mod_evaluate(self.libdeno_isolate, self.as_raw_ptr(), id)
};
self.check_last_exception()
}
}
struct LockerScope {
libdeno_isolate: *const libdeno::isolate,
}
impl LockerScope {
fn new(libdeno_isolate: *const libdeno::isolate) -> LockerScope {
unsafe { libdeno::deno_lock(libdeno_isolate) }
LockerScope { libdeno_isolate }
}
}
impl Drop for LockerScope {
fn drop(&mut self) {
unsafe { libdeno::deno_unlock(self.libdeno_isolate) }
}
}
impl Future for Isolate {
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type Output = Result<(), ErrBox>;
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fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
let inner = self.get_mut();
inner.waker.register(cx.waker());
inner.shared_init();
let mut overflow_response: Option<(OpId, Buf)> = None;
loop {
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// If there are any pending dyn_import futures, do those first.
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if !inner.pending_dyn_imports.is_empty() {
let poll_imports = inner.poll_dyn_imports(cx)?;
assert!(poll_imports.is_ready());
}
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// Now handle actual ops.
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inner.have_unpolled_ops = false;
#[allow(clippy::match_wild_err_arm)]
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match inner.pending_ops.poll_next_unpin(cx) {
Poll::Ready(Some(Err(_))) => panic!("unexpected op error"),
Poll::Ready(None) => break,
Poll::Pending => break,
Poll::Ready(Some(Ok((op_id, buf)))) => {
let successful_push = inner.shared.push(op_id, &buf);
if !successful_push {
// If we couldn't push the response to the shared queue, because
// there wasn't enough size, we will return the buffer via the
// legacy route, using the argument of deno_respond.
overflow_response = Some((op_id, buf));
break;
}
}
}
}
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if inner.shared.size() > 0 {
// Lock the current thread for V8.
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let locker = LockerScope::new(inner.libdeno_isolate);
inner.respond(None)?;
// The other side should have shifted off all the messages.
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assert_eq!(inner.shared.size(), 0);
drop(locker);
}
if overflow_response.is_some() {
// Lock the current thread for V8.
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let locker = LockerScope::new(inner.libdeno_isolate);
let (op_id, buf) = overflow_response.take().unwrap();
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inner.respond(Some((op_id, &buf)))?;
drop(locker);
}
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inner.check_promise_errors();
inner.check_last_exception()?;
// We're idle if pending_ops is empty.
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if inner.pending_ops.is_empty() && inner.pending_dyn_imports.is_empty() {
Poll::Ready(Ok(()))
} else {
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if inner.have_unpolled_ops {
inner.waker.wake();
}
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Poll::Pending
}
}
}
/// IsolateHandle is a thread safe handle on an Isolate. It exposed thread safe V8 functions.
#[derive(Clone)]
pub struct IsolateHandle {
shared_libdeno_isolate: Arc<Mutex<Option<*const libdeno::isolate>>>,
}
unsafe impl Send for IsolateHandle {}
impl IsolateHandle {
/// Terminate the execution of any currently running javascript.
/// After terminating execution it is probably not wise to continue using
/// the isolate.
pub fn terminate_execution(&self) {
unsafe {
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if let Some(isolate) = *self.shared_libdeno_isolate.lock().unwrap() {
libdeno::deno_terminate_execution(isolate)
}
}
}
}
pub fn js_check<T>(r: Result<T, ErrBox>) -> T {
if let Err(e) = r {
panic!(e.to_string());
}
r.unwrap()
}
#[cfg(test)]
pub mod tests {
use super::*;
use futures::future::lazy;
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use std::io;
use std::ops::FnOnce;
use std::sync::atomic::{AtomicUsize, Ordering};
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pub fn run_in_task<F>(f: F)
where
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F: FnOnce(&mut Context) + Send + 'static,
{
futures::executor::block_on(lazy(move |cx| f(cx)));
}
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fn poll_until_ready<F>(future: &mut F, max_poll_count: usize) -> F::Output
where
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F: Future + Unpin,
{
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let mut cx = Context::from_waker(futures::task::noop_waker_ref());
for _ in 0..max_poll_count {
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match future.poll_unpin(&mut cx) {
Poll::Pending => continue,
Poll::Ready(val) => return val,
}
}
panic!(
"Isolate still not ready after polling {} times.",
max_poll_count
)
}
pub enum Mode {
Async,
OverflowReqSync,
OverflowResSync,
OverflowReqAsync,
OverflowResAsync,
}
pub fn setup(mode: Mode) -> (Isolate, Arc<AtomicUsize>) {
let dispatch_count = Arc::new(AtomicUsize::new(0));
let dispatch_count_ = dispatch_count.clone();
let mut isolate = Isolate::new(StartupData::None, false);
let dispatcher =
move |control: &[u8], _zero_copy: Option<PinnedBuf>| -> CoreOp {
dispatch_count_.fetch_add(1, Ordering::Relaxed);
match mode {
Mode::Async => {
assert_eq!(control.len(), 1);
assert_eq!(control[0], 42);
let buf = vec![43u8, 0, 0, 0].into_boxed_slice();
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Op::Async(futures::future::ok(buf).boxed())
}
Mode::OverflowReqSync => {
assert_eq!(control.len(), 100 * 1024 * 1024);
let buf = vec![43u8, 0, 0, 0].into_boxed_slice();
Op::Sync(buf)
}
Mode::OverflowResSync => {
assert_eq!(control.len(), 1);
assert_eq!(control[0], 42);
let mut vec = Vec::<u8>::new();
vec.resize(100 * 1024 * 1024, 0);
vec[0] = 99;
let buf = vec.into_boxed_slice();
Op::Sync(buf)
}
Mode::OverflowReqAsync => {
assert_eq!(control.len(), 100 * 1024 * 1024);
let buf = vec![43u8, 0, 0, 0].into_boxed_slice();
Op::Async(futures::future::ok(buf).boxed())
}
Mode::OverflowResAsync => {
assert_eq!(control.len(), 1);
assert_eq!(control[0], 42);
let mut vec = Vec::<u8>::new();
vec.resize(100 * 1024 * 1024, 0);
vec[0] = 4;
let buf = vec.into_boxed_slice();
Op::Async(futures::future::ok(buf).boxed())
}
}
};
isolate.register_op("test", dispatcher);
js_check(isolate.execute(
"setup.js",
r#"
function assert(cond) {
if (!cond) {
throw Error("assert");
}
}
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 0);
(isolate, dispatch_count)
}
#[test]
fn test_dispatch() {
let (mut isolate, dispatch_count) = setup(Mode::Async);
js_check(isolate.execute(
"filename.js",
r#"
let control = new Uint8Array([42]);
Deno.core.send(1, control);
async function main() {
Deno.core.send(1, control);
}
main();
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 2);
}
#[test]
fn test_mods() {
let (mut isolate, dispatch_count) = setup(Mode::Async);
let mod_a = isolate
.mod_new(
true,
"a.js",
r#"
import { b } from 'b.js'
if (b() != 'b') throw Error();
let control = new Uint8Array([42]);
Deno.core.send(1, control);
"#,
)
.unwrap();
assert_eq!(dispatch_count.load(Ordering::Relaxed), 0);
let imports = isolate.mod_get_imports(mod_a);
assert_eq!(imports, vec!["b.js".to_string()]);
let mod_b = isolate
.mod_new(false, "b.js", "export function b() { return 'b' }")
.unwrap();
let imports = isolate.mod_get_imports(mod_b);
assert_eq!(imports.len(), 0);
let resolve_count = Arc::new(AtomicUsize::new(0));
let resolve_count_ = resolve_count.clone();
let mut resolve = move |specifier: &str, _referrer: deno_mod| -> deno_mod {
resolve_count_.fetch_add(1, Ordering::SeqCst);
assert_eq!(specifier, "b.js");
mod_b
};
js_check(isolate.mod_instantiate(mod_b, &mut resolve));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 0);
assert_eq!(resolve_count.load(Ordering::SeqCst), 0);
js_check(isolate.mod_instantiate(mod_a, &mut resolve));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 0);
assert_eq!(resolve_count.load(Ordering::SeqCst), 1);
js_check(isolate.mod_evaluate(mod_a));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
assert_eq!(resolve_count.load(Ordering::SeqCst), 1);
}
#[test]
fn test_poll_async_delayed_ops() {
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run_in_task(|cx| {
let (mut isolate, dispatch_count) = setup(Mode::Async);
js_check(isolate.execute(
"setup2.js",
r#"
let nrecv = 0;
Deno.core.setAsyncHandler((opId, buf) => {
nrecv++;
});
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 0);
js_check(isolate.execute(
"check1.js",
r#"
assert(nrecv == 0);
let control = new Uint8Array([42]);
Deno.core.send(1, control);
assert(nrecv == 0);
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
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assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Ok(_)) => true,
_ => false,
});
assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
js_check(isolate.execute(
"check2.js",
r#"
assert(nrecv == 1);
Deno.core.send(1, control);
assert(nrecv == 1);
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 2);
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assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Ok(_)) => true,
_ => false,
});
js_check(isolate.execute("check3.js", "assert(nrecv == 2)"));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 2);
// We are idle, so the next poll should be the last.
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assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Ok(_)) => true,
_ => false,
});
});
}
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struct MockImportStream(Vec<Result<RecursiveLoadEvent, ErrBox>>);
impl Stream for MockImportStream {
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type Item = Result<RecursiveLoadEvent, ErrBox>;
fn poll_next(
self: Pin<&mut Self>,
_cx: &mut Context,
) -> Poll<Option<Self::Item>> {
let inner = self.get_mut();
let event = if inner.0.is_empty() {
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None
} else {
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Some(inner.0.remove(0))
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};
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Poll::Ready(event)
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}
}
impl ImportStream for MockImportStream {
fn register(
&mut self,
module_data: SourceCodeInfo,
isolate: &mut Isolate,
) -> Result<(), ErrBox> {
let id = isolate.mod_new(
false,
&module_data.module_url_found,
&module_data.code,
)?;
println!(
"MockImportStream register {} {}",
id, module_data.module_url_found
);
Ok(())
}
}
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#[test]
fn dyn_import_err() {
// Test an erroneous dynamic import where the specified module isn't found.
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run_in_task(|cx| {
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let count = Arc::new(AtomicUsize::new(0));
let count_ = count.clone();
let mut isolate = Isolate::new(StartupData::None, false);
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isolate.set_dyn_import(move |_, specifier, referrer| {
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count_.fetch_add(1, Ordering::Relaxed);
assert_eq!(specifier, "foo.js");
assert_eq!(referrer, "dyn_import2.js");
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let err = io::Error::from(io::ErrorKind::NotFound);
let stream = MockImportStream(vec![Err(err.into())]);
Box::new(stream)
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});
js_check(isolate.execute(
"dyn_import2.js",
r#"
(async () => {
await import("foo.js");
})();
"#,
));
assert_eq!(count.load(Ordering::Relaxed), 1);
// We should get an error here.
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let result = isolate.poll_unpin(cx);
if let Poll::Ready(Ok(_)) = result {
unreachable!();
}
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})
}
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#[test]
fn dyn_import_err2() {
use std::convert::TryInto;
// Import multiple modules to demonstrate that after failed dynamic import
// another dynamic import can still be run
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run_in_task(|cx| {
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let count = Arc::new(AtomicUsize::new(0));
let count_ = count.clone();
let mut isolate = Isolate::new(StartupData::None, false);
isolate.set_dyn_import(move |_, specifier, referrer| {
let c = count_.fetch_add(1, Ordering::Relaxed);
match c {
0 => assert_eq!(specifier, "foo1.js"),
1 => assert_eq!(specifier, "foo2.js"),
2 => assert_eq!(specifier, "foo3.js"),
_ => unreachable!(),
}
assert_eq!(referrer, "dyn_import_error.js");
let source_code_info = SourceCodeInfo {
module_url_specified: specifier.to_owned(),
module_url_found: specifier.to_owned(),
code: "# not valid JS".to_owned(),
};
let stream = MockImportStream(vec![
Ok(RecursiveLoadEvent::Fetch(source_code_info)),
Ok(RecursiveLoadEvent::Instantiate(c.try_into().unwrap())),
]);
Box::new(stream)
});
js_check(isolate.execute(
"dyn_import_error.js",
r#"
(async () => {
await import("foo1.js");
})();
(async () => {
await import("foo2.js");
})();
(async () => {
await import("foo3.js");
})();
"#,
));
assert_eq!(count.load(Ordering::Relaxed), 3);
// Now each poll should return error
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assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Err(_)) => true,
_ => false,
});
assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Err(_)) => true,
_ => false,
});
assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Err(_)) => true,
_ => false,
});
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})
}
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#[test]
fn dyn_import_ok() {
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run_in_task(|cx| {
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let count = Arc::new(AtomicUsize::new(0));
let count_ = count.clone();
// Sometimes Rust is really annoying.
let mod_b = Arc::new(Mutex::new(0));
let mod_b2 = mod_b.clone();
let mut isolate = Isolate::new(StartupData::None, false);
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isolate.set_dyn_import(move |_id, specifier, referrer| {
let c = count_.fetch_add(1, Ordering::Relaxed);
match c {
0 => assert_eq!(specifier, "foo1.js"),
1 => assert_eq!(specifier, "foo2.js"),
_ => unreachable!(),
}
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assert_eq!(referrer, "dyn_import3.js");
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let mod_id = *mod_b2.lock().unwrap();
let source_code_info = SourceCodeInfo {
module_url_specified: "foo.js".to_owned(),
module_url_found: "foo.js".to_owned(),
code: "".to_owned(),
};
let stream = MockImportStream(vec![
Ok(RecursiveLoadEvent::Fetch(source_code_info)),
Ok(RecursiveLoadEvent::Instantiate(mod_id)),
]);
Box::new(stream)
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});
// Instantiate mod_b
{
let mut mod_id = mod_b.lock().unwrap();
*mod_id = isolate
.mod_new(false, "b.js", "export function b() { return 'b' }")
.unwrap();
let mut resolve = move |_specifier: &str,
_referrer: deno_mod|
-> deno_mod { unreachable!() };
js_check(isolate.mod_instantiate(*mod_id, &mut resolve));
}
// Dynamically import mod_b
js_check(isolate.execute(
"dyn_import3.js",
r#"
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(async () => {
let mod = await import("foo1.js");
if (mod.b() !== 'b') {
throw Error("bad1");
}
// And again!
mod = await import("foo2.js");
if (mod.b() !== 'b') {
throw Error("bad2");
}
})();
"#,
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));
assert_eq!(count.load(Ordering::Relaxed), 1);
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assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Ok(_)) => true,
_ => false,
});
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assert_eq!(count.load(Ordering::Relaxed), 2);
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assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Ok(_)) => true,
_ => false,
});
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assert_eq!(count.load(Ordering::Relaxed), 2);
})
}
#[test]
fn terminate_execution() {
let (tx, rx) = std::sync::mpsc::channel::<bool>();
let tx_clone = tx.clone();
let (mut isolate, _dispatch_count) = setup(Mode::Async);
let shared = isolate.shared_isolate_handle();
let t1 = std::thread::spawn(move || {
// allow deno to boot and run
std::thread::sleep(std::time::Duration::from_millis(100));
// terminate execution
shared.terminate_execution();
// allow shutdown
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std::thread::sleep(std::time::Duration::from_millis(200));
// unless reported otherwise the test should fail after this point
tx_clone.send(false).ok();
});
let t2 = std::thread::spawn(move || {
// run an infinite loop
let res = isolate.execute(
"infinite_loop.js",
r#"
let i = 0;
while (true) { i++; }
"#,
);
// execute() terminated, which means terminate_execution() was successful.
tx.send(true).ok();
if let Err(e) = res {
assert_eq!(e.to_string(), "Uncaught Error: execution terminated");
} else {
panic!("should return an error");
}
// make sure the isolate is still unusable
let res = isolate.execute("simple.js", "1+1;");
if let Err(e) = res {
assert_eq!(e.to_string(), "Uncaught Error: execution terminated");
} else {
panic!("should return an error");
}
});
if !rx.recv().unwrap() {
panic!("should have terminated")
}
t1.join().unwrap();
t2.join().unwrap();
}
#[test]
fn dangling_shared_isolate() {
let shared = {
// isolate is dropped at the end of this block
let (mut isolate, _dispatch_count) = setup(Mode::Async);
isolate.shared_isolate_handle()
};
// this should not SEGFAULT
shared.terminate_execution();
}
#[test]
fn overflow_req_sync() {
let (mut isolate, dispatch_count) = setup(Mode::OverflowReqSync);
js_check(isolate.execute(
"overflow_req_sync.js",
r#"
let asyncRecv = 0;
Deno.core.setAsyncHandler((opId, buf) => { asyncRecv++ });
// Large message that will overflow the shared space.
let control = new Uint8Array(100 * 1024 * 1024);
let response = Deno.core.dispatch(1, control);
assert(response instanceof Uint8Array);
assert(response.length == 4);
assert(response[0] == 43);
assert(asyncRecv == 0);
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
}
#[test]
fn overflow_res_sync() {
// TODO(ry) This test is quite slow due to memcpy-ing 100MB into JS. We
// should optimize this.
let (mut isolate, dispatch_count) = setup(Mode::OverflowResSync);
js_check(isolate.execute(
"overflow_res_sync.js",
r#"
let asyncRecv = 0;
Deno.core.setAsyncHandler((opId, buf) => { asyncRecv++ });
// Large message that will overflow the shared space.
let control = new Uint8Array([42]);
let response = Deno.core.dispatch(1, control);
assert(response instanceof Uint8Array);
assert(response.length == 100 * 1024 * 1024);
assert(response[0] == 99);
assert(asyncRecv == 0);
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
}
#[test]
fn overflow_req_async() {
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run_in_task(|cx| {
let (mut isolate, dispatch_count) = setup(Mode::OverflowReqAsync);
js_check(isolate.execute(
"overflow_req_async.js",
r#"
let asyncRecv = 0;
Deno.core.setAsyncHandler((opId, buf) => {
assert(opId == 1);
assert(buf.byteLength === 4);
assert(buf[0] === 43);
asyncRecv++;
});
// Large message that will overflow the shared space.
let control = new Uint8Array(100 * 1024 * 1024);
let response = Deno.core.dispatch(1, control);
// Async messages always have null response.
assert(response == null);
assert(asyncRecv == 0);
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
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assert!(match isolate.poll_unpin(cx) {
Poll::Ready(Ok(_)) => true,
_ => false,
});
js_check(isolate.execute("check.js", "assert(asyncRecv == 1);"));
});
}
#[test]
fn overflow_res_async() {
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run_in_task(|_cx| {
// TODO(ry) This test is quite slow due to memcpy-ing 100MB into JS. We
// should optimize this.
let (mut isolate, dispatch_count) = setup(Mode::OverflowResAsync);
js_check(isolate.execute(
"overflow_res_async.js",
r#"
let asyncRecv = 0;
Deno.core.setAsyncHandler((opId, buf) => {
assert(opId == 1);
assert(buf.byteLength === 100 * 1024 * 1024);
assert(buf[0] === 4);
asyncRecv++;
});
// Large message that will overflow the shared space.
let control = new Uint8Array([42]);
let response = Deno.core.dispatch(1, control);
assert(response == null);
assert(asyncRecv == 0);
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 1);
poll_until_ready(&mut isolate, 3).unwrap();
js_check(isolate.execute("check.js", "assert(asyncRecv == 1);"));
});
}
#[test]
fn overflow_res_multiple_dispatch_async() {
// TODO(ry) This test is quite slow due to memcpy-ing 100MB into JS. We
// should optimize this.
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run_in_task(|_cx| {
let (mut isolate, dispatch_count) = setup(Mode::OverflowResAsync);
js_check(isolate.execute(
"overflow_res_multiple_dispatch_async.js",
r#"
let asyncRecv = 0;
Deno.core.setAsyncHandler((opId, buf) => {
assert(opId === 1);
assert(buf.byteLength === 100 * 1024 * 1024);
assert(buf[0] === 4);
asyncRecv++;
});
// Large message that will overflow the shared space.
let control = new Uint8Array([42]);
let response = Deno.core.dispatch(1, control);
assert(response == null);
assert(asyncRecv == 0);
// Dispatch another message to verify that pending ops
// are done even if shared space overflows
Deno.core.dispatch(1, control);
"#,
));
assert_eq!(dispatch_count.load(Ordering::Relaxed), 2);
poll_until_ready(&mut isolate, 3).unwrap();
js_check(isolate.execute("check.js", "assert(asyncRecv == 2);"));
});
}
#[test]
fn test_pre_dispatch() {
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run_in_task(|mut cx| {
let (mut isolate, _dispatch_count) = setup(Mode::OverflowResAsync);
js_check(isolate.execute(
"bad_op_id.js",
r#"
let thrown;
try {
Deno.core.dispatch(100, []);
} catch (e) {
thrown = e;
}
assert(thrown == "Unknown op id: 100");
"#,
));
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if let Poll::Ready(Err(_)) = isolate.poll_unpin(&mut cx) {
unreachable!();
}
});
}
#[test]
fn test_js() {
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run_in_task(|mut cx| {
let (mut isolate, _dispatch_count) = setup(Mode::Async);
js_check(
isolate.execute(
"shared_queue_test.js",
include_str!("shared_queue_test.js"),
),
);
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if let Poll::Ready(Err(_)) = isolate.poll_unpin(&mut cx) {
unreachable!();
}
});
}
#[test]
fn will_snapshot() {
let snapshot = {
let mut isolate = Isolate::new(StartupData::None, true);
js_check(isolate.execute("a.js", "a = 1 + 2"));
let s = isolate.snapshot().unwrap();
drop(isolate);
s
};
let startup_data = StartupData::LibdenoSnapshot(snapshot);
let mut isolate2 = Isolate::new(startup_data, false);
js_check(isolate2.execute("check.js", "if (a != 3) throw Error('x')"));
}
}