Files
react-native/ReactCommon/fabric/mounting/MountingCoordinator.cpp
T
Valentin Shergin 8cf9505bd2 Fabric: MountingCoordinator::waitForTransaction(...)
Summary:
`MountingCoordinator::waitForTransaction()` allows waiting for a new coming transaction synchronously, as efficient as waiting for a mutex.
This feature can be used to implement more high-level synchronous rendering APIs.

Reviewed By: mdvacca

Differential Revision: D17629425

fbshipit-source-id: acd91b941e4d6d43bc4518f332a1604e14506be9
2019-10-08 21:49:55 -07:00

112 lines
2.9 KiB
C++

/**
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
#include "MountingCoordinator.h"
#ifdef RN_SHADOW_TREE_INTROSPECTION
#include <glog/logging.h>
#endif
#include <condition_variable>
#include <react/mounting/Differentiator.h>
#include <react/mounting/ShadowViewMutation.h>
#include <react/utils/TimeUtils.h>
namespace facebook {
namespace react {
MountingCoordinator::MountingCoordinator(ShadowTreeRevision baseRevision)
: surfaceId_(baseRevision.getRootShadowNode().getSurfaceId()),
baseRevision_(baseRevision) {
#ifdef RN_SHADOW_TREE_INTROSPECTION
stubViewTree_ = stubViewTreeFromShadowNode(baseRevision_.getRootShadowNode());
#endif
}
SurfaceId MountingCoordinator::getSurfaceId() const {
return surfaceId_;
}
void MountingCoordinator::push(ShadowTreeRevision &&revision) const {
{
std::lock_guard<std::mutex> lock(mutex_);
assert(revision.getNumber() > baseRevision_.getNumber());
assert(
!lastRevision_.has_value() ||
revision.getNumber() != lastRevision_->getNumber());
if (!lastRevision_.has_value() ||
lastRevision_->getNumber() < revision.getNumber()) {
lastRevision_ = std::move(revision);
}
}
signal_.notify_all();
}
void MountingCoordinator::revoke() const {
std::lock_guard<std::mutex> lock(mutex_);
lastRevision_.reset();
}
bool MountingCoordinator::waitForTransaction(
std::chrono::duration<double> timeout) const {
std::unique_lock<std::mutex> lock(mutex_);
return signal_.wait_for(
lock, timeout, [this]() { return lastRevision_.has_value(); });
}
better::optional<MountingTransaction> MountingCoordinator::pullTransaction()
const {
std::lock_guard<std::mutex> lock(mutex_);
if (!lastRevision_.has_value()) {
return {};
}
number_++;
auto telemetry = lastRevision_->getTelemetry();
telemetry.willDiff();
auto mutations = calculateShadowViewMutations(
baseRevision_.getRootShadowNode(), lastRevision_->getRootShadowNode());
telemetry.didDiff();
#ifdef RN_SHADOW_TREE_INTROSPECTION
stubViewTree_.mutate(mutations);
auto stubViewTree =
stubViewTreeFromShadowNode(lastRevision_->getRootShadowNode());
if (stubViewTree_ != stubViewTree) {
LOG(ERROR) << "Old tree:"
<< "\n"
<< baseRevision_.getRootShadowNode().getDebugDescription()
<< "\n";
LOG(ERROR) << "New tree:"
<< "\n"
<< lastRevision_->getRootShadowNode().getDebugDescription()
<< "\n";
LOG(ERROR) << "Mutations:"
<< "\n"
<< getDebugDescription(mutations);
assert(false);
}
#endif
baseRevision_ = std::move(*lastRevision_);
lastRevision_.reset();
return MountingTransaction{
surfaceId_, number_, std::move(mutations), telemetry};
}
} // namespace react
} // namespace facebook