Ivan Inozemtsev
6e33c95463
Adds shared libraries for embedding Dart VM and new API (runtime/engine/include/dart_engine.h). TEST=tests/standalone/embedder_samples_test.dart Cq-Include-Trybots: luci.dart.try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-asan-linux-release-x64-try,vm-aot-dwarf-linux-product-x64-try,vm-aot-dyn-linux-debug-x64-try,vm-aot-linux-debug-simarm_x64-try,vm-aot-linux-debug-simriscv32-try,vm-aot-linux-debug-simriscv64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-linux-product-x64-try,vm-aot-linux-release-arm64-try,vm-aot-linux-release-simarm_x64-try,vm-aot-linux-release-x64-try,vm-aot-mac-product-arm64-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-msan-linux-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-tsan-linux-release-x64-try,vm-aot-ubsan-linux-release-x64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,vm-aot-win-product-x64-try,vm-aot-win-release-x64-try,vm-appjit-linux-debug-x64-try,vm-appjit-linux-product-x64-try,vm-appjit-linux-release-x64-try,vm-asan-linux-release-arm64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-android-product-arm-try,vm-ffi-android-product-arm64c-try,vm-ffi-android-release-arm-try,vm-ffi-android-release-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-fuchsia-release-arm64-try,vm-fuchsia-release-x64-try,vm-gcc-linux-try,vm-linux-debug-ia32-try,vm-linux-debug-simriscv32-try,vm-linux-debug-simriscv64-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-linux-release-arm64-try,vm-linux-release-ia32-try,vm-linux-release-simarm-try,vm-linux-release-x64-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-mac-release-arm64-try,vm-mac-release-x64-try,vm-msan-linux-release-arm64-try,vm-msan-linux-release-x64-try,vm-msvc-windows-try,vm-reload-linux-debug-x64-try,vm-reload-linux-release-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-reload-rollback-linux-release-x64-try,vm-tsan-linux-release-arm64-try,vm-tsan-linux-release-x64-try,vm-ubsan-linux-release-arm64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-x64-try,vm-win-debug-x64c-try,vm-win-release-ia32-try,vm-win-release-x64-try Change-Id: Ia4e4d1b871ddef515cfb2f4639bdaa9fe3676936 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/402860 Reviewed-by: Slava Egorov <vegorov@google.com> Reviewed-by: Martin Kustermann <kustermann@google.com> Commit-Queue: Martin Kustermann <kustermann@google.com>
2.2 KiB
Dart Engine
The include/dart_engine.h provides additional functions to embed the Dart VM
and to call Dart functions from kernel and AOT snapshots. It is not intended to
be a full-featured API, and should be used together with dart_api.h.
It is intended for reusing of existing Dart code in non-Dart programs, and allows to use Dart snapshots as shared libraries: the caller can start one or several isolates from Dart snapshots and call Dart functions from it.
Comparing to dart_api.h it brings the following:
- Full initialization of Dart VM, including initializing core libraries.
- Easier handling of isolate messages
- Lock-guarded functions to enter/exit isolates.
See examples in samples/embedder for usages of the API.
Handling isolate messages
In dart_api.h there are two possible ways to handle asynchronous
isolate messages:
Dart_MessageNotifyCallback: Users can pass a callback to get notifications about messages to handle, but handling messages still requires entering an isolate, entering a scope, callingDart_HandleMessage, and then leaving a scope and an isolate.Dart_RunLoop: Users can invoke it on a separate thread, but then they won't be able to enter isolates from other threads.
As an alternative, dart_engine.h provides a simpler function
DartEngine_HandleMessage, which encapsulates isolate and scope management, and
it allows to specify per isolate / default message schedulers, which only need
to schedule an execution DartEngine_HandleMessage with the right isolate.
Users can create their own DartEngine_MessageScheduler struct and pass it to
DartEngine_SetMessageScheduler / DartEngine_SetDefaultMessageScheduler. See
samples/embedder/run_timer_async.cc and samples/embedder/run_timer.cc
examples.
Entering / leaving isolates
Because engine API uses its own message handling, it is important to use
DartEngine_AcquireIsolate / DartEngine_ReleaseIsolate instead of
Dart_EnterIsolate / Dart_ExitIsolate. DartEngine_AcquireIsolate blocks
until an isolate can be entered by trying to obtain an internal lock (which is
released by DartEngine_ReleaseIsolate), while Dart_EnterIsolate crashes if
some other thread has entered the same isolate.