On FreeBSD some symbols like `environ` or `__progname` are not exported
anywhere and are filled in by the dynamic loader. `environ` is
a special case because we make use of it explicitly so we need to mark
it a weak symbol so the linker doesn't complain.
The issue with that refactor was that the same fd can be used in more
than one notifier. This reverts us back to using 2 members to track the
notifiers in play.
POLLHUP is set when the remote end of the monitored fd is closed. There
may still be some buffered data to read from the socket, however. Some
systems do not set POLLIN in these cases. So we should just always try
to read from fds when we receive this event.
One benefit of using `poll` over `select` is that we can re-use the poll
structure list. But there's no guarantee that the underlying system will
reset the `revents` field back to 0. So let's explicitly do so.
To prepare for an upcoming Utf16String, this migrates Utf16View to store
its data as a char16_t. Most function definitions are moved inline and
made constexpr.
This also adds a UDL to construct a Utf16View from a string literal:
auto string = u"hello"sv;
This let's us remove the NTTP Utf16View constructor, as we have found
that such constructors bloat binary size quite a bit.
Once an event loop manager is installed, we want to be sure we only use
that manager in the current process going forward. Mixing event loop
implementations can only cause problems.
More to the point, this ensures that we have installed the AppKit or Qt
event loop managers before the first time EventLoopManager::the() is
invoked. Now that we defer this installation until we know whether we
are running headlessly, we want to be extra sure that we have done so
before any services using the event loop have started.
the goal is to rely on fontconfig for font directory resolution. it
doesn't seem like it would be appropritate to call to fontconfig funcs
from within the LibCore.
i'm not 100% confident that FontDatabase is the correct place.. seems
okay?
This fixes two race conditions and ASAN crashes in the test for the
same.
The first comes from destroying the internals struct, which was
previously using the standard, thread-unsafe RefCounted CRTP. The
second is from destroying the name, which is secretly another
RefCounted object, in a thread-unsafe manner.
It is currently possible to hit this limit on pages with large numbers
of images. This temporary workaround prevents some WPT tests with large
numbers of images from failing.
This was previously used by the WPT runner to determine the git hash
of a particular WPT run. This mechanism is no longer used, since it
doesn't work with chunked WPT runs.
This is a remnant from SerenityOS. Let's avoid confusion as to why we
negate errno when we call Error::from_syscall just to negate it again
when we store the error code.
This method was removed in e015a43b51
However, it was not exactly *unused* as the commit message would say.
This method was the only thing that allowed spin_until to exit when
the event loop was cancelled. This happens normally when IPC connections
are closed, but also when the process is killed.
The logic to properly handle process exit from event loop spins needs to
actually notify the caller that their goal condition was not met though.
That will be handled in a later commit.
This fixes a really nasty EventLoop bug which I debugged for 2 weeks.
The spin_until([&]{return completed_tasks == total_tasks;}) in
TraversableNavigable::check_if_unloading_is_canceled spins forever.
Cause of the bug:
check_if_unloading_is_canceled is called deferred
check_if_unloading_is_canceled creates a task:
queue_global_task(..., [&] {
...
completed_tasks++;
}));
This task is never executed.
queue_global_task calls TaskQueue::add
void TaskQueue::add(task)
{
m_tasks.append(task);
m_event_loop->schedule();
}
void HTML::EventLoop::schedule()
{
if (!m_system_event_loop_timer)
m_system_event_loop_timer = Timer::create_single_shot(
0, // delay
[&] { process(); });
if (!m_system_event_loop_timer->is_active())
m_system_event_loop_timer->restart();
}
EventLoop::process executes one task from task queue and calls
schedule again if there are more tasks.
So task processing relies on one single-shot zero-delay timer,
m_system_event_loop_timer.
Timers and other notification events are handled by Core::EventLoop
and Core::ThreadEventQueue, these are different from HTML::EventLoop
and HTML::TaskQueue mentioned above.
check_if_unloading_is_canceled is called using deferred_invoke
mechanism, different from m_system_event_loop_timer,
see Navigable::navigate and Core::EventLoop::deferred_invoke.
The core of the problem is that Core::EventLoop::pump is called again
(from spin_until) after timer fired but before its handler is executed.
In ThreadEventQueue::process events are moved into local variable before
executing. The first of those events is check_if_unloading_is_canceled.
One of the rest events is Web::HTML::EventLoop::process sheduled in
EventLoop::schedule using m_system_event_loop_timer.
When check_if_unloading_is_canceled calls queue_global_task its
m_system_event_loop_timer is still active because Timer::timer_event
was not yet called, so the timer is not restarted.
But Timer::timer_event (and hence EventLoop::process) will never execute
because check_if_unloading_is_canceled calls spin_until after
queue_global_task, and EventLoop::process is no longer in
event_queue.m_private->queued_events.
By making a single-shot timer manually-reset we are allowing it to fire
several times. So when spin_until is executed m_system_event_loop_timer
is fired again. Not an ideal solution, but this is the best I could
come up with. This commit makes the behavior match EventLoopImplUnix,
in which single-shot timer can also fire several times.
Adding event_queue.process(); at the start of pump like in EvtLoopImplQt
doesn't fix the problem.
Note: Timer::start calls EventReceiver::start_timer, which calls
EventLoop::register_timer with should_reload always set to true
(single-shot vs periodic are handled in Timer::timer_event instead),
so I use static_cast<Timer&>(object).is_single_shot() instead of
!should_reload.
This fixes the problem when none of the timers or notifiers get
executed if wake() is called frequently.
Note that calling WaitForMultipleObjects repeatedly until it fails
will not work because rapidly firing timer can get all the attention.
That's why I check every event individually with WaitForSingleObject.
This behavior matches EventLoopImplementationUnix.
and unregister_timer in EventLoopManagerWindows
Destructors for thread local objects are called before destructors of
global not thread local objects.
This is a partial stack of the problem, thread_data is already
destroyed at this point:
>WebContent.exe!Core::ThreadData::the
WebContent.exe!Core::EventLoopManagerWindows::unregister_notifier
WebContent.exe!Core::EventLoop::unregister_notifier
WebContent.exe!Core::Notifier::set_enabled
WebContent.exe!Core::LocalSocket::~LocalSocket
WebContent.exe!Requests::RequestClient::~RequestClient
WebContent.exe!Web::`dynamic atexit destructor for 's_resource_loader'
It's generally considered a security issue to use non-format string
literals. We would likely just crash in practice, but let's avoid the
issue altogether.
This is a homegrown implementation that wasn't actually used in
dependent classes. If this is needed in the future, using OpenSSL would
probably be a better option.
LibCore's list of ignored header files for Swift was missing the Apple
only files on non-Apple platforms. Additionally, any generic glue code
cannot use -fobjc-arc, so we need to rely on -fblocks only.
Previously, we only returned the first result that looked like an IPv6
or IPv4 address.
This cropped up when attempting to connect to https://cxbyte.me/ whilst
IPv6 on the server wasn't working. Since we only returned the first
result, which happened to be the IPv6 address, we wasn't able to
connect.
Returning all results allows curl to attempt to connect to a different
IP if one of them isn't working, and potentially make a successful
connection.
This removes the use of StringBuilder::OutputType (which was ByteString,
and only used by the JSON classes). And it removes the StringBuilder
template parameter from the serialization methods; this was only ever
used with StringBuilder, so a template is pretty overkill here.
