ladybird/Libraries/LibWeb/HighResolutionTime/TimeOrigin.cpp
Shannon Booth 218ac86b67 LibWeb: Use relevant principal settings for HighResolutionTime
Fixes a crash when setting the timestamps when creating a DOM event
within a ShadowRealm.
2024-11-30 11:55:11 +01:00

97 lines
4.5 KiB
C++

/*
* Copyright (c) 2022, Andreas Kling <andreas@ladybird.org>
* Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Time.h>
#include <LibWeb/HTML/Scripting/Environments.h>
#include <LibWeb/HighResolutionTime/TimeOrigin.h>
namespace Web::HighResolutionTime {
// https://w3c.github.io/hr-time/#dfn-get-time-origin-timestamp
DOMHighResTimeStamp get_time_origin_timestamp(JS::Object const& global)
{
(void)global;
// To get time origin timestamp, given a global object global, run the following steps, which return a duration:
// FIXME: 1. Let timeOrigin be global's relevant settings object's time origin.
auto time_origin = 0;
// Each group of environment settings objects that could possibly communicate in any way
// has an estimated monotonic time of the Unix epoch, a moment on the monotonic clock,
// whose value is initialized by the following steps:
// !. Let wall time be the wall clock's unsafe current time.
struct timeval tv;
gettimeofday(&tv, nullptr);
auto wall_time = tv.tv_sec * 1000.0 + tv.tv_usec / 1000.0;
// 2. Let monotonic time be the monotonic clock's unsafe current time.
auto monotonic_time = unsafe_shared_current_time();
// 3. Let epoch time be monotonic time - (wall time - Unix epoch)
auto epoch_time = monotonic_time - (wall_time - 0);
// 4. Initialize the estimated monotonic time of the Unix epoch to the result of calling coarsen time with epoch time
auto estimated_monotonic_time = coarsen_time(epoch_time);
// 2. Return the duration from the estimated monotonic time of the Unix epoch to timeOrigin.
return estimated_monotonic_time - time_origin;
}
// https://w3c.github.io/hr-time/#dfn-coarsen-time
DOMHighResTimeStamp coarsen_time(DOMHighResTimeStamp timestamp, bool cross_origin_isolated_capability)
{
// FIXME: Implement this.
(void)cross_origin_isolated_capability;
return timestamp;
}
// https://w3c.github.io/hr-time/#dfn-current-high-resolution-time
DOMHighResTimeStamp current_high_resolution_time(JS::Object const& global)
{
// The current high resolution time given a global object current global must return the result
// of relative high resolution time given unsafe shared current time and current global.
return HighResolutionTime::relative_high_resolution_time(HighResolutionTime::unsafe_shared_current_time(), global);
}
// https://w3c.github.io/hr-time/#dfn-relative-high-resolution-time
// https://pr-preview.s3.amazonaws.com/w3c/hr-time/pull/168.html#dfn-relative-high-resolution-time
DOMHighResTimeStamp relative_high_resolution_time(DOMHighResTimeStamp time, JS::Object const& global)
{
// 1. Let settings be the global's relevant principal settings object.
auto& settings = HTML::relevant_principal_settings_object(global);
// 2. Let coarse time be the result of calling coarsen time with time and settings's cross-origin isolated capability.
auto coarse_time = coarsen_time(time, settings.cross_origin_isolated_capability() == HTML::CanUseCrossOriginIsolatedAPIs::Yes);
// 2. Return the relative high resolution coarse time for coarse time and global.
return relative_high_resolution_coarsen_time(coarse_time, global);
}
// https://w3c.github.io/hr-time/#dfn-relative-high-resolution-coarse-time
DOMHighResTimeStamp relative_high_resolution_coarsen_time(DOMHighResTimeStamp coarsen_time, JS::Object const& global)
{
// The relative high resolution coarse time given a DOMHighResTimeStamp coarseTime and a global object global, is the difference between coarseTime and the result of calling get time origin timestamp with global.
return coarsen_time - get_time_origin_timestamp(global);
}
// https://w3c.github.io/hr-time/#dfn-coarsened-shared-current-time
DOMHighResTimeStamp coarsened_shared_current_time(bool cross_origin_isolated_capability)
{
// The coarsened shared current time given an optional boolean crossOriginIsolatedCapability (default false), must return the result of calling coarsen time with the unsafe shared current time and crossOriginIsolatedCapability.
return coarsen_time(unsafe_shared_current_time(), cross_origin_isolated_capability);
}
// https://w3c.github.io/hr-time/#dfn-unsafe-shared-current-time
DOMHighResTimeStamp unsafe_shared_current_time()
{
// The unsafe shared current time must return the current value of the shared monotonic clock.
// Note: This is in milliseconds (stored as a double).
return MonotonicTime::now().nanoseconds() / 1.0e6;
}
}