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// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef FLUTTER_RUNTIME_RUNTIME_CONTROLLER_H_
#define FLUTTER_RUNTIME_RUNTIME_CONTROLLER_H_
#include <memory>
#include <vector>
#include "flutter/assets/asset_manager.h"
#include "flutter/common/task_runners.h"
#include "flutter/flow/layers/layer_tree.h"
#include "flutter/fml/macros.h"
#include "flutter/fml/mapping.h"
#include "flutter/lib/ui/io_manager.h"
#include "flutter/lib/ui/painting/image_generator_registry.h"
#include "flutter/lib/ui/text/font_collection.h"
#include "flutter/lib/ui/ui_dart_state.h"
#include "flutter/lib/ui/volatile_path_tracker.h"
#include "flutter/lib/ui/window/platform_configuration.h"
#include "flutter/lib/ui/window/pointer_data_packet.h"
#include "flutter/runtime/dart_vm.h"
#include "flutter/runtime/platform_data.h"
#include "rapidjson/document.h"
#include "rapidjson/stringbuffer.h"
namespace flutter {
class Scene;
class RuntimeDelegate;
class View;
class Window;
//------------------------------------------------------------------------------
/// Represents an instance of a running root isolate with window bindings. In
/// normal operation, a single instance of this object is owned by the engine
/// per shell. This object may only be created, used, and collected on the UI
/// task runner. Window state queried by the root isolate is stored by this
/// object. In cold-restart scenarios, the engine may collect this before
/// installing a new runtime controller in its place. The Clone method may be
/// used by the engine to copy the currently accumulated window state so it can
/// be referenced by the new runtime controller.
///
/// When `RuntimeController` is created, it takes some time before the root
/// isolate becomes ready. Operation during this gap is stored by
/// `RuntimeController` and flushed to the Dart VM when the isolate becomes
/// ready before the entrypoint function. See `PlatformData`.
///
class RuntimeController : public PlatformConfigurationClient {
public:
//----------------------------------------------------------------------------
/// @brief Creates a new instance of a runtime controller. This is
/// usually only done by the engine instance associated with the
/// shell.
///
/// @param client The runtime delegate. This is
/// usually the `Engine` instance.
/// @param vm A reference to a running Dart VM.
/// The runtime controller must be
/// collected before the VM is
/// destroyed (this order is
/// guaranteed by the shell).
/// @param[in] idle_notification_callback The idle notification callback.
/// This allows callers to run native
/// code in isolate scope when the VM
/// is about to be notified that the
/// engine is going to be idle.
/// @param[in] platform_data The window data (if exists).
/// @param[in] isolate_create_callback The isolate create callback. This
/// allows callers to run native code
/// in isolate scope on the UI task
/// runner as soon as the root isolate
/// has been created.
/// @param[in] isolate_shutdown_callback The isolate shutdown callback.
/// This allows callers to run native
/// code in isolate scoped on the UI
/// task runner just as the root
/// isolate is about to be torn down.
/// @param[in] persistent_isolate_data Unstructured persistent read-only
/// data that the root isolate can
/// access in a synchronous manner.
/// @param[in] context Engine-owned state which is
/// accessed by the root dart isolate.
///
RuntimeController(
RuntimeDelegate& p_client,
DartVM* vm,
fml::RefPtr<const DartSnapshot> p_isolate_snapshot,
const std::function<void(int64_t)>& idle_notification_callback,
const PlatformData& platform_data,
const fml::closure& isolate_create_callback,
const fml::closure& isolate_shutdown_callback,
std::shared_ptr<const fml::Mapping> p_persistent_isolate_data,
const UIDartState::Context& context);
//----------------------------------------------------------------------------
/// @brief Create a RuntimeController that shares as many resources as
/// possible with the calling RuntimeController such that together
/// they occupy less memory.
/// @return A RuntimeController with a running isolate.
/// @see RuntimeController::RuntimeController
///
std::unique_ptr<RuntimeController> Spawn(
RuntimeDelegate& p_client,
std::string advisory_script_uri,
std::string advisory_script_entrypoint,
const std::function<void(int64_t)>& idle_notification_callback,
const fml::closure& isolate_create_callback,
const fml::closure& isolate_shutdown_callback,
const std::shared_ptr<const fml::Mapping>& persistent_isolate_data,
fml::WeakPtr<IOManager> io_manager,
fml::WeakPtr<ImageDecoder> image_decoder,
fml::WeakPtr<ImageGeneratorRegistry> image_generator_registry,
fml::TaskRunnerAffineWeakPtr<SnapshotDelegate> snapshot_delegate) const;
// |PlatformConfigurationClient|
~RuntimeController() override;
//----------------------------------------------------------------------------
/// @brief Launches the isolate using the window data associated with
/// this runtime controller. Before this call, the Dart isolate
/// has not been initialized. On successful return, the caller can
/// assume that the isolate is in the
/// `DartIsolate::Phase::Running` phase.
///
/// This call will fail if a root isolate is already running. To
/// re-create an isolate with the window data associated with this
/// runtime controller, `Clone` this runtime controller and
/// Launch an isolate in that runtime controller instead.
///
/// @param[in] settings The per engine instance settings.
/// @param[in] root_isolate_create_callback A callback invoked before the
/// root isolate has launched the Dart
/// program, but after it has been
/// created. This is called without
/// isolate scope, and after any root
/// isolate callback in the settings.
/// @param[in] dart_entrypoint The dart entrypoint. If
/// `std::nullopt` or empty, `main` will
/// be attempted.
/// @param[in] dart_entrypoint_library The dart entrypoint library. If
/// `std::nullopt` or empty, the core
/// library will be attempted.
/// @param[in] dart_entrypoint_args Arguments passed as a List<String>
/// to Dart's entrypoint function.
/// @param[in] isolate_configuration The isolate configuration
///
/// @return If the isolate could be launched and guided to the
/// `DartIsolate::Phase::Running` phase.
///
[[nodiscard]] bool LaunchRootIsolate(
const Settings& settings,
const fml::closure& root_isolate_create_callback,
std::optional<std::string> dart_entrypoint,
std::optional<std::string> dart_entrypoint_library,
const std::vector<std::string>& dart_entrypoint_args,
std::unique_ptr<IsolateConfiguration> isolate_configuration);
//----------------------------------------------------------------------------
/// @brief Clone the runtime controller. Launching an isolate with a
/// cloned runtime controller will use the same snapshots and
/// copies all window data to the new instance. This is usually
/// only used in the debug runtime mode to support the
/// cold-restart scenario.
///
/// @return A clone of the existing runtime controller.
///
std::unique_ptr<RuntimeController> Clone() const;
//----------------------------------------------------------------------------
/// @brief Notify the isolate that a new view is available.
///
/// A view must be added before other methods can refer to it,
/// including the implicit view. Adding a view that already exists
/// triggers an assertion.
///
/// @param[in] view_id The ID of the new view.
/// @param[in] viewport_metrics The initial viewport metrics for the view.
///
bool AddView(int64_t view_id, const ViewportMetrics& view_metrics);
//----------------------------------------------------------------------------
/// @brief Notify the isolate that a view is no longer available.
///
/// Removing a view that does not exist triggers an assertion.
///
/// The implicit view (kFlutterImplicitViewId) should never be
/// removed. Doing so triggers an assertion.
///
/// @param[in] view_id The ID of the view.
///
bool RemoveView(int64_t view_id);
//----------------------------------------------------------------------------
/// @brief Forward the specified viewport metrics to the running isolate.
/// If the isolate is not running, these metrics will be saved and
/// flushed to the isolate when it starts.
///
/// @param[in] view_id The ID for the view that `metrics` describes.
/// @param[in] metrics The window's viewport metrics.
///
/// @return If the window metrics were forwarded to the running isolate.
///
bool SetViewportMetrics(int64_t view_id, const ViewportMetrics& metrics);
//----------------------------------------------------------------------------
/// @brief Forward the specified display metrics to the running isolate.
/// If the isolate is not running, these metrics will be saved and
/// flushed to the isolate when it starts.
///
/// @param[in] displays The available displays.
bool SetDisplays(const std::vector<DisplayData>& displays);
//----------------------------------------------------------------------------
/// @brief Forward the specified locale data to the running isolate. If
/// the isolate is not running, this data will be saved and
/// flushed to the isolate when it starts running.
///
/// @deprecated The persistent isolate data must be used for this purpose
/// instead.
///
/// @param[in] locale_data The locale data. This should consist of groups of
/// 4 strings, each group representing a single locale.
///
/// @return If the locale data was forwarded to the running isolate.
///
bool SetLocales(const std::vector<std::string>& locale_data);
//----------------------------------------------------------------------------
/// @brief Forward the user settings data to the running isolate. If the
/// isolate is not running, this data will be saved and flushed to
/// the isolate when it starts running.
///
/// @deprecated The persistent isolate data must be used for this purpose
/// instead.
///
/// @param[in] data The user settings data.
///
/// @return If the user settings data was forwarded to the running
/// isolate.
///
bool SetUserSettingsData(const std::string& data);
//----------------------------------------------------------------------------
/// @brief Forward the initial lifecycle state data to the running
/// isolate. If the isolate is not running, this data will be
/// saved and flushed to the isolate when it starts running.
/// After the isolate starts running, the current lifecycle
/// state is pushed to it via the "flutter/lifecycle" channel.
///
/// @deprecated The persistent isolate data must be used for this purpose
/// instead.
///
/// @param[in] data The lifecycle state data.
///
/// @return If the lifecycle state data was forwarded to the running
/// isolate.
///
bool SetInitialLifecycleState(const std::string& data);
//----------------------------------------------------------------------------
/// @brief Notifies the running isolate about whether the semantics tree
/// should be generated or not. If the isolate is not running,
/// this preference will be saved and flushed to the isolate when
/// it starts running.
///
/// @param[in] enabled Indicates whether to generate the semantics tree.
///
/// @return If the semantics tree generation preference was forwarded to
/// the running isolate.
///
bool SetSemanticsEnabled(bool enabled);
//----------------------------------------------------------------------------
/// @brief Forward the preference of accessibility features that must be
/// enabled in the semantics tree to the running isolate. If the
/// isolate is not running, this data will be saved and flushed to
/// the isolate when it starts running.
///
/// @param[in] flags The accessibility features that must be generated in
/// the semantics tree.
///
/// @return If the preference of accessibility features was forwarded to
/// the running isolate.
///
bool SetAccessibilityFeatures(int32_t flags);
//----------------------------------------------------------------------------
/// @brief Notifies the running isolate that it should start generating a
/// new frame.
///
/// @see `Engine::BeginFrame` for more context.
///
/// @param[in] frame_time The point at which the current frame interval
/// began. May be used by animation interpolators,
/// physics simulations, etc.
///
/// @return If notification to begin frame rendering was delivered to the
/// running isolate.
///
bool BeginFrame(fml::TimePoint frame_time, uint64_t frame_number);
//----------------------------------------------------------------------------
/// @brief Dart code cannot fully measure the time it takes for a
/// specific frame to be rendered. This is because Dart code only
/// runs on the UI task runner. That is only a small part of the
/// overall frame workload. The raster task runner frame workload
/// is executed on a thread where Dart code cannot run (and hence
/// instrument). Besides, due to the pipelined nature of rendering
/// in Flutter, there may be multiple frame workloads being
/// processed at any given time. However, for non-Timeline based
/// profiling, it is useful for trace collection and processing to
/// happen in Dart. To do this, the raster task runner frame
/// workloads need to be instrumented separately. After a set
/// number of these profiles have been gathered, they need to be
/// reported back to Dart code. The engine reports this extra
/// instrumentation information back to Dart code running on the
/// engine by invoking this method at predefined intervals.
///
/// @see `Engine::ReportTimings`, `FrameTiming`
///
/// @param[in] timings Collection of `FrameTiming::kCount` * `n` timestamps
/// for `n` frames whose timings have not been reported
/// yet. A collection of integers is reported here for
/// easier conversions to Dart objects. The timestamps
/// are measured against the system monotonic clock
/// measured in microseconds.
///
bool ReportTimings(std::vector<int64_t> timings);
//----------------------------------------------------------------------------
/// @brief Notify the Dart VM that no frame workloads are expected on the
/// UI task runner till the specified deadline. The VM uses this
/// opportunity to perform garbage collection operations is a
/// manner that interferes as little as possible with frame
/// rendering.
///
/// NotifyIdle is advisory. The VM may or may not run a garbage collection
/// when this is called, and will eventually perform garbage collections even
/// if it is not called or it is called with insufficient deadlines.
///
/// The garbage collection mechanism and its thresholds are internal
/// implementation details and absolutely no guarantees are made about the
/// threshold discussed below. This discussion is also an oversimplification
/// but hopefully serves to calibrate expectations about GC behavior:
/// * When the Dart VM and its root isolate are initialized, the memory
/// consumed upto that point are treated as a baseline.
/// * A fixed percentage of the memory consumed (~20%) over the baseline is
/// treated as the hard threshold.
/// * The memory in play is divided into old space and new space. The new
/// space is typically very small and fills up rapidly.
/// * The baseline plus the threshold is considered the old space while the
/// small new space is a separate region (typically a few pages).
/// * The total old space size minus the max new space size is treated as the
/// soft threshold.
/// * In a world where there is no call to NotifyIdle, when the total
/// allocation exceeds the soft threshold, a concurrent mark is initiated in
/// the VM. There is a “small” pause that occurs when the concurrent mark is
/// initiated and another pause when the mark concludes and a sweep is
/// initiated.
/// * If the total allocations exceeds the hard threshold, a “big”
/// stop-the-world pause is initiated.
/// * If after either the sweep after the concurrent mark, or, the
/// stop-the-world pause, the consumption returns to be below the soft
/// threshold, the dance begins anew.
/// * If after both the “small” and “big” pauses, memory usage is still over
/// the hard threshold, i.e, the objects are still reachable, that amount of
/// memory is treated as the new baseline and a fixed percentage of the new
/// baseline over the new baseline is now the new hard threshold.
/// * Updating the baseline will continue till memory for the updated old
/// space can be allocated from the operating system. These allocations will
/// typically fail due to address space exhaustion on 32-bit systems and
/// page table exhaustion on 64-bit systems.
/// * NotifyIdle initiates the concurrent mark preemptively. The deadline is
/// used by the VM to determine if the corresponding sweep can be performed
/// within the deadline. This way, jank due to “small” pauses can be
/// ameliorated.
/// * There is no ability to stop a “big” pause on reaching the hard threshold
/// in the old space. The best you can do is release (by making them
/// unreachable) objects eagerly so that the are marked as unreachable in
/// the concurrent mark initiated by either reaching the soft threshold or
/// an explicit NotifyIdle.
/// * If you are running out of memory, its because too many large objects
/// were allocation and remained reachable such that the old space kept
/// growing till it could grow no more.
/// * At the edges of allocation thresholds, failures can occur gracefully if
/// the instigating allocation was made in the Dart VM or rather gracelessly
/// if the allocation is made by some native component.
///
/// @see `Dart_TimelineGetMicros`
///
/// @bug The `deadline` argument must be converted to `std::chrono`
/// instead of a raw integer.
///
/// @param[in] deadline The deadline is used by the VM to determine if the
/// corresponding sweep can be performed within the deadline.
///
/// @return If the idle notification was forwarded to the running isolate.
///
virtual bool NotifyIdle(fml::TimeDelta deadline);
//----------------------------------------------------------------------------
/// @brief Notify the Dart VM that the attached flutter view has been
/// destroyed. This gives the Dart VM to perform some cleanup
/// activities e.g: perform garbage collection to free up any
/// unused memory.
///
/// NotifyDestroyed is advisory. The VM may or may not perform any clean up
/// activities.
///
virtual bool NotifyDestroyed();
//----------------------------------------------------------------------------
/// @brief Returns if the root isolate is running. The isolate must be
/// transitioned to the running phase manually. The isolate can
/// stop running if it terminates execution on its own.
///
/// @return True if root isolate running, False otherwise.
///
virtual bool IsRootIsolateRunning();
//----------------------------------------------------------------------------
/// @brief Dispatch the specified platform message to running root
/// isolate.
///
/// @param[in] message The message to dispatch to the isolate.
///
/// @return If the message was dispatched to the running root isolate.
/// This may fail is an isolate is not running.
///
virtual bool DispatchPlatformMessage(
std::unique_ptr<PlatformMessage> message);
//----------------------------------------------------------------------------
/// @brief Dispatch the specified pointer data message to the running
/// root isolate.
///
/// @param[in] packet The pointer data message to dispatch to the isolate.
///
/// @return If the pointer data message was dispatched. This may fail is
/// an isolate is not running.
///
bool DispatchPointerDataPacket(const PointerDataPacket& packet);
//----------------------------------------------------------------------------
/// @brief Dispatch the semantics action to the specified accessibility
/// node.
///
/// @param[in] node_id The identified of the accessibility node.
/// @param[in] action The semantics action to perform on the specified
/// accessibility node.
/// @param[in] args Optional data that applies to the specified action.
///
/// @return If the semantics action was dispatched. This may fail if an
/// isolate is not running.
///
bool DispatchSemanticsAction(int32_t node_id,
SemanticsAction action,
fml::MallocMapping args);
//----------------------------------------------------------------------------
/// @brief Gets the main port identifier of the root isolate.
///
/// @return The main port identifier. If no root isolate is running,
/// returns `ILLEGAL_PORT`.
///
Dart_Port GetMainPort();
//----------------------------------------------------------------------------
/// @brief Gets the debug name of the root isolate. But default, the
/// debug name of the isolate is derived from its advisory script
/// URI, advisory main entrypoint and its main port name. For
/// example, "main.dart$main-1234" where the script URI is
/// "main.dart", the entrypoint is "main" and the port name
/// "1234". Once launched, the isolate may re-christen itself
/// using a name it selects via `setIsolateDebugName` in
/// `window.dart`. This name is purely advisory and only used by
/// instrumentation and reporting purposes.
///
/// @return The debug name of the root isolate.
///
std::string GetIsolateName();
//----------------------------------------------------------------------------
/// @brief Returns if the root isolate has any live receive ports.
///
/// @return True if there are live receive ports, False otherwise. Return
/// False if the root isolate is not running as well.
///
bool HasLivePorts();
//----------------------------------------------------------------------------
/// @brief Get the last error encountered by the microtask queue.
///
/// @return The last error encountered by the microtask queue.
///
tonic::DartErrorHandleType GetLastError();
//----------------------------------------------------------------------------
/// @brief Get the service ID of the root isolate if the root isolate is
/// running.
///
/// @return The root isolate service id.
///
std::optional<std::string> GetRootIsolateServiceID() const;
//----------------------------------------------------------------------------
/// @brief Get the return code specified by the root isolate (if one is
/// present).
///
/// @return The root isolate return code if the isolate has specified one.
///
std::optional<uint32_t> GetRootIsolateReturnCode();
//----------------------------------------------------------------------------
/// @brief Get an identifier that represents the Dart isolate group the
/// root isolate is in.
///
/// @return The root isolate group identifier, zero if one can't
/// be established.
uint64_t GetRootIsolateGroup() const;
//--------------------------------------------------------------------------
/// @brief Loads the Dart shared library into the Dart VM. When the
/// Dart library is loaded successfully, the Dart future
/// returned by the originating loadLibrary() call completes.
///
/// The Dart compiler may generate separate shared libraries
/// files called 'loading units' when libraries are imported
/// as deferred. Each of these shared libraries are identified
/// by a unique loading unit id. Callers should open and resolve
/// a SymbolMapping from the shared library. The Mappings should
/// be moved into this method, as ownership will be assumed by the
/// dart root isolate after successful loading and released after
/// shutdown of the root isolate. The loading unit may not be
/// used after isolate shutdown. If loading fails, the mappings
/// will be released.
///
/// This method is paired with a RequestDartDeferredLibrary
/// invocation that provides the embedder with the loading unit id
/// of the deferred library to load.
///
///
/// @param[in] loading_unit_id The unique id of the deferred library's
/// loading unit, as passed in by
/// RequestDartDeferredLibrary.
///
/// @param[in] snapshot_data Dart snapshot data of the loading unit's
/// shared library.
///
/// @param[in] snapshot_data Dart snapshot instructions of the loading
/// unit's shared library.
///
void LoadDartDeferredLibrary(
intptr_t loading_unit_id,
std::unique_ptr<const fml::Mapping> snapshot_data,
std::unique_ptr<const fml::Mapping> snapshot_instructions);
//--------------------------------------------------------------------------
/// @brief Indicates to the dart VM that the request to load a deferred
/// library with the specified loading unit id has failed.
///
/// The dart future returned by the initiating loadLibrary() call
/// will complete with an error.
///
/// @param[in] loading_unit_id The unique id of the deferred library's
/// loading unit, as passed in by
/// RequestDartDeferredLibrary.
///
/// @param[in] error_message The error message that will appear in the
/// dart Future.
///
/// @param[in] transient A transient error is a failure due to
/// temporary conditions such as no network.
/// Transient errors allow the dart VM to
/// re-request the same deferred library and
/// loading_unit_id again. Non-transient
/// errors are permanent and attempts to
/// re-request the library will instantly
/// complete with an error.
virtual void LoadDartDeferredLibraryError(intptr_t loading_unit_id,
const std::string error_message,
bool transient);
// |PlatformConfigurationClient|
void RequestDartDeferredLibrary(intptr_t loading_unit_id) override;
// |PlatformConfigurationClient|
std::shared_ptr<const fml::Mapping> GetPersistentIsolateData() override;
const fml::WeakPtr<IOManager>& GetIOManager() const {
return context_.io_manager;
}
virtual DartVM* GetDartVM() const { return vm_; }
const fml::RefPtr<const DartSnapshot>& GetIsolateSnapshot() const {
return isolate_snapshot_;
}
const PlatformData& GetPlatformData() const { return platform_data_; }
const fml::RefPtr<SkiaUnrefQueue>& GetSkiaUnrefQueue() const {
return context_.unref_queue;
}
const fml::TaskRunnerAffineWeakPtr<SnapshotDelegate>& GetSnapshotDelegate()
const {
return context_.snapshot_delegate;
}
std::weak_ptr<const DartIsolate> GetRootIsolate() const {
return root_isolate_;
}
protected:
/// Constructor for Mocks.
RuntimeController(RuntimeDelegate& p_client, const TaskRunners& task_runners);
private:
struct Locale {
Locale(std::string language_code_,
std::string country_code_,
std::string script_code_,
std::string variant_code_);
~Locale();
std::string language_code;
std::string country_code;
std::string script_code;
std::string variant_code;
};
RuntimeDelegate& client_;
DartVM* const vm_;
fml::RefPtr<const DartSnapshot> isolate_snapshot_;
std::function<void(int64_t)> idle_notification_callback_;
PlatformData platform_data_;
std::weak_ptr<DartIsolate> root_isolate_;
std::weak_ptr<DartIsolate> spawning_isolate_;
std::optional<uint32_t> root_isolate_return_code_;
const fml::closure isolate_create_callback_;
const fml::closure isolate_shutdown_callback_;
std::shared_ptr<const fml::Mapping> persistent_isolate_data_;
UIDartState::Context context_;
bool has_flushed_runtime_state_ = false;
PlatformConfiguration* GetPlatformConfigurationIfAvailable();
bool FlushRuntimeStateToIsolate();
// |PlatformConfigurationClient|
std::string DefaultRouteName() override;
// |PlatformConfigurationClient|
void ScheduleFrame() override;
// |PlatformConfigurationClient|
void Render(Scene* scene, double width, double height) override;
// |PlatformConfigurationClient|
void UpdateSemantics(SemanticsUpdate* update) override;
// |PlatformConfigurationClient|
void HandlePlatformMessage(std::unique_ptr<PlatformMessage> message) override;
// |PlatformConfigurationClient|
FontCollection& GetFontCollection() override;
// |PlatformConfigurationClient|
std::shared_ptr<AssetManager> GetAssetManager() override;
// |PlatformConfigurationClient|
void UpdateIsolateDescription(const std::string isolate_name,
int64_t isolate_port) override;
// |PlatformConfigurationClient|
void SetNeedsReportTimings(bool value) override;
// |PlatformConfigurationClient|
std::unique_ptr<std::vector<std::string>> ComputePlatformResolvedLocale(
const std::vector<std::string>& supported_locale_data) override;
// |PlatformConfigurationClient|
void SendChannelUpdate(std::string name, bool listening) override;
// |PlatformConfigurationClient|
double GetScaledFontSize(double unscaled_font_size,
int configuration_id) const override;
FML_DISALLOW_COPY_AND_ASSIGN(RuntimeController);
};
} // namespace flutter
#endif // FLUTTER_RUNTIME_RUNTIME_CONTROLLER_H_