Files
sdk/samples/embedder/run_timer.cc
T
Tess Strickland acd16c6aa7 [pkg/vm] Add tool for generating DartEngine shims from entry points.
This is an initial cut of a tool for automatically creating shims for
C/C++ programs using the entry point annotations in Dart code. The tool
has two required arguments:

* the .dill file containing the kernel representation of the Dart code
* the base path of the header and implementation files to create

With a base path of 'dir/name', the header file is created as
'dir/name.h' and the implementation file is created as 'dir/name.cc'.
In addition, 'dir/name.h' is used as a basis for creating a
#ifndef/#define/#endif header guard around the header contents.


The created shims are specific to a single package, either

* a user-specified package, provided via '-p'/'--package', or
* the package of the main method

If the user does not specify a package and there is no main method
in the .dill file, the tool fails.


Each shim takes the following arguments in order when applicable:

* the isolate in which to perform the requested operation,
* the instantiated type of the generic class (for invoking, setting, or
  getting constructors, static methods, and static fields)
* the instance (for invoking, getting, or setting instance methods and
  fields)
* the type arguments (for retrieving nullable or non-nullable
  instantiated types of a generic class)
* the arguments (for invoking, setting, or getting constructors,
  methods, and fields)


The generated shims:

* cache the package library, types for non-generic classes, and
  types for generic classes instantiated with default type arguments.
  The cached persistent handles are cleared if any of the methods
  are called with a different isolate from the one used to populate
  the cache.
* automatically handle conversions between C int64_t <=> Dart int
  and C double <=> Dart double.


By default, shims are not created for allocation or initializing
uninitialized instances. To create such shims, use the '-u' command
line argument.


Currently, shims are not created for methods that take optional
or named arguments. To report an error if a shim cannot be created
for any entry points, use the '-e' command line argument.

TEST=tests/standalone/embedder_samples_test

Change-Id: Ibdf3b52d900ba98038528178485f295c5868ac9d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/410500
Reviewed-by: Ivan Inozemtsev <iinozemtsev@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
2025-03-20 03:53:10 -07:00

96 lines
2.6 KiB
C++

// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include <condition_variable>
#include <iostream>
#include <mutex>
#include <queue>
#include <thread>
#include "helpers.h"
#include "include/dart_api.h"
#include "include/dart_engine.h"
#include "timer.h"
// Queue-based message handler, running on a separate thread.
class ThreadedMessageHandler {
public:
void Run() {
is_running = true;
while (is_running) {
Dart_Isolate isolate;
{
std::unique_lock notifications_lock(notifications_mutex_);
can_pop_.wait(notifications_lock);
if (notifications_.empty()) {
continue;
}
isolate = notifications_.front();
notifications_.pop();
}
DartEngine_HandleMessage(isolate);
}
}
void Notify(Dart_Isolate isolate) {
std::unique_lock notifications_lock(notifications_mutex_);
notifications_.push(isolate);
can_pop_.notify_one();
}
void Stop() {
is_running = false;
can_pop_.notify_one();
}
static void ScheduleDartMessage(Dart_Isolate isolate, void* context) {
reinterpret_cast<ThreadedMessageHandler*>(context)->Notify(isolate);
}
private:
std::queue<Dart_Isolate> notifications_;
std::condition_variable can_pop_;
std::atomic<bool> is_running;
std::mutex notifications_mutex_;
};
int main(int argc, char** argv) {
if (argc == 1) {
std::cerr << "Must specify snapshot path" << std::endl;
std::exit(1);
}
char* error = nullptr;
// Start an event loop on a separate thread and use it as a default
// scheduler.
ThreadedMessageHandler message_handler;
std::thread message_handler_thread(&ThreadedMessageHandler::Run,
&message_handler);
DartEngine_SetDefaultMessageScheduler(
{ThreadedMessageHandler::ScheduleDartMessage, &message_handler});
// Load snapshot and create an isolate
DartEngine_SnapshotData snapshot_data = AutoSnapshotFromFile(argv[1], &error);
CheckError(error, "reading snapshot");
Dart_Isolate isolate = DartEngine_CreateIsolate(snapshot_data, &error);
CheckError(error, "creating isolate");
// Call Dart function to start a timer.
Call_startTimer(isolate, 1);
// Wait a bit.
std::this_thread::sleep_for(std::chrono::milliseconds(100));
// Stop the timer.
Call_stopTimer(isolate);
// Get timer value.
std::cout << "Ticks: " << Get_ticks(isolate) << std::endl;
// Stop event loop.
message_handler.Stop();
message_handler_thread.join();
DartEngine_Shutdown();
}