Majorly simplify process.nextTick

This commit is contained in:
Alex Hultman 2019-03-01 19:47:27 +01:00
parent 06e987db04
commit 0a4fb24b9f
2 changed files with 2 additions and 60 deletions

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@ -24,13 +24,6 @@
using namespace v8; using namespace v8;
/* These two are definitely static */ /* These two are definitely static */
/* Warning: having nextTickQueue items at loop fallthrough is not allowed.
* Process will crash/hang due to destruction of V8 resouces after V8 itself
* has been destroyed. Either enforce nextTick calls to keep the loop rolling
* via for instance setTimeout or setImmediate, or make sure to drain completely
* the queue at process.on('beforeExit'). */
std::vector<UniquePersistent<Function>> nextTickQueue;
Isolate *isolate; Isolate *isolate;
#include "Utilities.h" #include "Utilities.h"
@ -39,43 +32,12 @@ Isolate *isolate;
#include "HttpRequestWrapper.h" #include "HttpRequestWrapper.h"
#include "AppWrapper.h" #include "AppWrapper.h"
/* We are not compatible with Node.js nextTick for performance (and standalone) reasons */
void nextTick(const FunctionCallbackInfo<Value> &args) {
nextTickQueue.emplace_back(UniquePersistent<Function>(isolate, Local<Function>::Cast(args[0])));
}
/* Used for debugging */ /* Used for debugging */
void print(const FunctionCallbackInfo<Value> &args) { void print(const FunctionCallbackInfo<Value> &args) {
NativeString nativeString(isolate, args[0]); NativeString nativeString(isolate, args[0]);
std::cout << nativeString.getString() << std::endl; std::cout << nativeString.getString() << std::endl;
} }
/* Does not guarantee empty queue because of recursive nextTick calls.
* Should return int queueSize after calling queued items, so that
* proper while(processNextTickQueueImpl()) can be done */
int processNextTickQueueImpl(Isolate *isolate) {
/* Run async continuations, promises and other V8-queued tasks */
isolate->RunMicrotasks();
if (nextTickQueue.size()) {
/* Swap queues for recursive calls */
std::vector<UniquePersistent<Function>> currentNextTickQueue = std::move(nextTickQueue);
HandleScope hs(isolate);
for (UniquePersistent<Function> &f : currentNextTickQueue) {
Local<Function>::New(isolate, f)->Call(isolate->GetCurrentContext()->Global(), 0, nullptr);
}
}
return nextTickQueue.size();
}
/* It is possible to call this at process.beforeExit until it returns 0. */
void processNextTickQueue(const FunctionCallbackInfo<Value> &args) {
args.GetReturnValue().Set(Integer::New(isolate, processNextTickQueueImpl(isolate)));
}
/* todo: Put this function and all inits of it in its own header */ /* todo: Put this function and all inits of it in its own header */
void uWS_us_listen_socket_close(const FunctionCallbackInfo<Value> &args) { void uWS_us_listen_socket_close(const FunctionCallbackInfo<Value> &args) {
us_listen_socket_close((struct us_listen_socket *) External::Cast(*args[0])->Value()); us_listen_socket_close((struct us_listen_socket *) External::Cast(*args[0])->Value());
@ -85,27 +47,15 @@ void Main(Local<Object> exports) {
/* I guess we store this statically */ /* I guess we store this statically */
isolate = exports->GetIsolate(); isolate = exports->GetIsolate();
/* We want this */ /* We want this so that we can redefine process.nextTick to using the V8 native microtask queue */
isolate->SetMicrotasksPolicy(MicrotasksPolicy::kAuto); isolate->SetMicrotasksPolicy(MicrotasksPolicy::kAuto);
/* Register our own nextTick handlers */
uWS::Loop::defaultLoop()->setPostHandler([](uWS::Loop *) {
processNextTickQueueImpl(isolate);
});
/* We also do need it on pre */
uWS::Loop::defaultLoop()->setPreHandler([](uWS::Loop *) {
processNextTickQueueImpl(isolate);
});
/* Hook up our timers */ /* Hook up our timers */
us_loop_integrate((us_loop *) uWS::Loop::defaultLoop()); us_loop_integrate((us_loop *) uWS::Loop::defaultLoop());
/* uWS namespace */ /* uWS namespace */
exports->Set(String::NewFromUtf8(isolate, "App"), FunctionTemplate::New(isolate, uWS_App<uWS::App>)->GetFunction()); exports->Set(String::NewFromUtf8(isolate, "App"), FunctionTemplate::New(isolate, uWS_App<uWS::App>)->GetFunction());
exports->Set(String::NewFromUtf8(isolate, "SSLApp"), FunctionTemplate::New(isolate, uWS_App<uWS::SSLApp>)->GetFunction()); exports->Set(String::NewFromUtf8(isolate, "SSLApp"), FunctionTemplate::New(isolate, uWS_App<uWS::SSLApp>)->GetFunction());
exports->Set(String::NewFromUtf8(isolate, "nextTick"), FunctionTemplate::New(isolate, nextTick)->GetFunction());
exports->Set(String::NewFromUtf8(isolate, "processNextTickQueue"), FunctionTemplate::New(isolate, processNextTickQueue)->GetFunction());
exports->Set(String::NewFromUtf8(isolate, "print"), FunctionTemplate::New(isolate, print)->GetFunction()); exports->Set(String::NewFromUtf8(isolate, "print"), FunctionTemplate::New(isolate, print)->GetFunction());
/* Expose some µSockets functions directly under uWS namespace */ /* Expose some µSockets functions directly under uWS namespace */

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@ -20,18 +20,10 @@ module.exports = (() => {
const uWS = require(`./uws_${process.platform}_${process.versions.modules}.node`); const uWS = require(`./uws_${process.platform}_${process.versions.modules}.node`);
/* We are not compatible with Node.js nextTick and/or domains */ /* We are not compatible with Node.js nextTick and/or domains */
process.nextTick = (f, ...args) => { process.nextTick = (f, ...args) => {
uWS.nextTick(() => { Promise.resolve().then(() => {
f(...args); f(...args);
}); });
}; };
process.on('beforeExit', () => {
if (uWS.processNextTickQueue()) {
setImmediate(() => {
});
}
});
/* process.nextTick = setImmediate; */
return uWS; return uWS;
} catch (e) { } catch (e) {
throw new Error('This version of µWS is not compatible with your Node.js build.\n\n' + e.toString()); throw new Error('This version of µWS is not compatible with your Node.js build.\n\n' + e.toString());