ladybird/Libraries/LibCore/CEventLoop.cpp
Andreas Kling 411d293961 LibCore+LibGUI: Don't fire timers in non-visible windows by default
LibCore timers now have a TimerShouldFireWhenNotVisible flag which is
set to "No" by default.

If "No", the timer will not be fired by the event loop if it's within
a CObject tree whose nearest GWindow ancestor is currently not visible
for timer purposes. (Specificially, this means that the window is
either minimized or fully occluded, and so does not want to fire timers
just to update the UI.)

This is another nice step towards a calm and serene operating system.
2019-12-29 16:03:36 +01:00

476 lines
14 KiB
C++

#include <AK/JsonArray.h>
#include <AK/JsonObject.h>
#include <AK/JsonValue.h>
#include <AK/Time.h>
#include <LibCore/CEvent.h>
#include <LibCore/CEventLoop.h>
#include <LibCore/CLocalSocket.h>
#include <LibCore/CNotifier.h>
#include <LibCore/CObject.h>
#include <LibCore/CSyscallUtils.h>
#include <LibThread/Lock.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>
//#define CEVENTLOOP_DEBUG
//#define DEFERRED_INVOKE_DEBUG
static CEventLoop* s_main_event_loop;
static Vector<CEventLoop*>* s_event_loop_stack;
HashMap<int, NonnullOwnPtr<CEventLoop::EventLoopTimer>>* CEventLoop::s_timers;
HashTable<CNotifier*>* CEventLoop::s_notifiers;
int CEventLoop::s_next_timer_id = 1;
int CEventLoop::s_wake_pipe_fds[2];
RefPtr<CLocalServer> CEventLoop::s_rpc_server;
class RPCClient : public CObject {
C_OBJECT(RPCClient)
public:
explicit RPCClient(RefPtr<CLocalSocket> socket)
: m_socket(move(socket))
{
add_child(*m_socket);
m_socket->on_ready_to_read = [this] {
i32 length;
int nread = m_socket->read((u8*)&length, sizeof(length));
if (nread == 0) {
dbg() << "RPC client disconnected";
shutdown();
return;
}
ASSERT(nread == sizeof(length));
auto request = m_socket->read(length);
auto request_json = JsonValue::from_string(request);
if (!request_json.is_object()) {
dbg() << "RPC client sent invalid request";
shutdown();
return;
}
handle_request(request_json.as_object());
};
}
virtual ~RPCClient() override
{
}
void send_response(const JsonObject& response)
{
auto serialized = response.to_string();
i32 length = serialized.length();
m_socket->write((const u8*)&length, sizeof(length));
m_socket->write(serialized);
}
void handle_request(const JsonObject& request)
{
auto type = request.get("type").as_string_or({});
if (type.is_null()) {
dbg() << "RPC client sent request without type field";
return;
}
if (type == "Identify") {
JsonObject response;
response.set("type", type);
response.set("pid", getpid());
#ifdef __serenity__
char buffer[1024];
if (get_process_name(buffer, sizeof(buffer)) >= 0) {
response.set("process_name", buffer);
} else {
response.set("process_name", JsonValue());
}
#endif
send_response(response);
return;
}
if (type == "GetAllObjects") {
JsonObject response;
response.set("type", type);
JsonArray objects;
for (auto& object : CObject::all_objects()) {
JsonObject json_object;
object.save_to(json_object);
objects.append(move(json_object));
}
response.set("objects", move(objects));
send_response(response);
return;
}
if (type == "Disconnect") {
shutdown();
return;
}
}
void shutdown()
{
// FIXME: This is quite a hackish way to clean ourselves up.
delete this;
}
private:
RefPtr<CLocalSocket> m_socket;
};
CEventLoop::CEventLoop()
{
if (!s_event_loop_stack) {
s_event_loop_stack = new Vector<CEventLoop*>;
s_timers = new HashMap<int, NonnullOwnPtr<CEventLoop::EventLoopTimer>>;
s_notifiers = new HashTable<CNotifier*>;
}
if (!s_main_event_loop) {
s_main_event_loop = this;
#if defined(SOCK_NONBLOCK)
int rc = pipe2(s_wake_pipe_fds, O_CLOEXEC);
#else
int rc = pipe(s_wake_pipe_fds);
fcntl(s_wake_pipe_fds[0], F_SETFD, FD_CLOEXEC);
fcntl(s_wake_pipe_fds[1], F_SETFD, FD_CLOEXEC);
#endif
ASSERT(rc == 0);
s_event_loop_stack->append(this);
auto rpc_path = String::format("/tmp/rpc.%d", getpid());
rc = unlink(rpc_path.characters());
if (rc < 0 && errno != ENOENT) {
perror("unlink");
ASSERT_NOT_REACHED();
}
s_rpc_server = CLocalServer::construct();
s_rpc_server->set_name("CEventLoop_RPC_server");
bool listening = s_rpc_server->listen(rpc_path);
ASSERT(listening);
s_rpc_server->on_ready_to_accept = [&] {
auto client_socket = s_rpc_server->accept();
ASSERT(client_socket);
// NOTE: RPCClient will delete itself in RPCClient::shutdown().
(void)RPCClient::construct(move(client_socket)).leak_ref();
};
}
#ifdef CEVENTLOOP_DEBUG
dbg() << getpid() << " CEventLoop constructed :)";
#endif
}
CEventLoop::~CEventLoop()
{
}
CEventLoop& CEventLoop::main()
{
ASSERT(s_main_event_loop);
return *s_main_event_loop;
}
CEventLoop& CEventLoop::current()
{
CEventLoop* event_loop = s_event_loop_stack->last();
ASSERT(event_loop != nullptr);
return *event_loop;
}
void CEventLoop::quit(int code)
{
dbg() << "CEventLoop::quit(" << code << ")";
m_exit_requested = true;
m_exit_code = code;
}
void CEventLoop::unquit()
{
dbg() << "CEventLoop::unquit()";
m_exit_requested = false;
m_exit_code = 0;
}
struct CEventLoopPusher {
public:
CEventLoopPusher(CEventLoop& event_loop)
: m_event_loop(event_loop)
{
if (&m_event_loop != s_main_event_loop) {
m_event_loop.take_pending_events_from(CEventLoop::current());
s_event_loop_stack->append(&event_loop);
}
}
~CEventLoopPusher()
{
if (&m_event_loop != s_main_event_loop) {
s_event_loop_stack->take_last();
CEventLoop::current().take_pending_events_from(m_event_loop);
}
}
private:
CEventLoop& m_event_loop;
};
int CEventLoop::exec()
{
CEventLoopPusher pusher(*this);
for (;;) {
if (m_exit_requested)
return m_exit_code;
pump();
}
ASSERT_NOT_REACHED();
}
void CEventLoop::pump(WaitMode mode)
{
if (m_queued_events.is_empty())
wait_for_event(mode);
decltype(m_queued_events) events;
{
LOCKER(m_lock);
events = move(m_queued_events);
}
for (int i = 0; i < events.size(); ++i) {
auto& queued_event = events.at(i);
#ifndef __clang__
ASSERT(queued_event.event);
#endif
auto* receiver = queued_event.receiver.ptr();
auto& event = *queued_event.event;
#ifdef CEVENTLOOP_DEBUG
if (receiver)
dbg() << "CEventLoop: " << *receiver << " event " << (int)event.type();
#endif
if (!receiver) {
switch (event.type()) {
case CEvent::Quit:
ASSERT_NOT_REACHED();
return;
default:
dbg() << "Event type " << event.type() << " with no receiver :(";
}
} else if (event.type() == CEvent::Type::DeferredInvoke) {
#ifdef DEFERRED_INVOKE_DEBUG
printf("DeferredInvoke: receiver=%s{%p}\n", receiver->class_name(), receiver);
#endif
static_cast<CDeferredInvocationEvent&>(event).m_invokee(*receiver);
} else {
NonnullRefPtr<CObject> protector(*receiver);
receiver->dispatch_event(event);
}
if (m_exit_requested) {
LOCKER(m_lock);
#ifdef CEVENTLOOP_DEBUG
dbg() << "CEventLoop: Exit requested. Rejigging " << (events.size() - i) << " events.";
#endif
decltype(m_queued_events) new_event_queue;
new_event_queue.ensure_capacity(m_queued_events.size() + events.size());
for (; i < events.size(); ++i)
new_event_queue.unchecked_append(move(events[i]));
new_event_queue.append(move(m_queued_events));
m_queued_events = move(new_event_queue);
return;
}
}
}
void CEventLoop::post_event(CObject& receiver, NonnullOwnPtr<CEvent>&& event)
{
LOCKER(m_lock);
#ifdef CEVENTLOOP_DEBUG
dbg() << "CEventLoop::post_event: {" << m_queued_events.size() << "} << receiver=" << receiver << ", event=" << event;
#endif
m_queued_events.append({ receiver.make_weak_ptr(), move(event) });
}
void CEventLoop::wait_for_event(WaitMode mode)
{
fd_set rfds;
fd_set wfds;
FD_ZERO(&rfds);
FD_ZERO(&wfds);
int max_fd = 0;
auto add_fd_to_set = [&max_fd](int fd, fd_set& set) {
FD_SET(fd, &set);
if (fd > max_fd)
max_fd = fd;
};
int max_fd_added = -1;
add_fd_to_set(s_wake_pipe_fds[0], rfds);
max_fd = max(max_fd, max_fd_added);
for (auto& notifier : *s_notifiers) {
if (notifier->event_mask() & CNotifier::Read)
add_fd_to_set(notifier->fd(), rfds);
if (notifier->event_mask() & CNotifier::Write)
add_fd_to_set(notifier->fd(), wfds);
if (notifier->event_mask() & CNotifier::Exceptional)
ASSERT_NOT_REACHED();
}
bool queued_events_is_empty;
{
LOCKER(m_lock);
queued_events_is_empty = m_queued_events.is_empty();
}
timeval now;
struct timeval timeout = { 0, 0 };
bool should_wait_forever = false;
if (mode == WaitMode::WaitForEvents) {
if (!s_timers->is_empty() && queued_events_is_empty) {
gettimeofday(&now, nullptr);
get_next_timer_expiration(timeout);
timeval_sub(timeout, now, timeout);
} else {
should_wait_forever = true;
}
} else {
should_wait_forever = false;
}
int marked_fd_count = CSyscallUtils::safe_syscall(select, max_fd + 1, &rfds, &wfds, nullptr, should_wait_forever ? nullptr : &timeout);
if (FD_ISSET(s_wake_pipe_fds[0], &rfds)) {
char buffer[32];
auto nread = read(s_wake_pipe_fds[0], buffer, sizeof(buffer));
if (nread < 0) {
perror("read from wake pipe");
ASSERT_NOT_REACHED();
}
ASSERT(nread > 0);
}
if (!s_timers->is_empty()) {
gettimeofday(&now, nullptr);
}
for (auto& it : *s_timers) {
auto& timer = *it.value;
if (!timer.has_expired(now))
continue;
if (it.value->fire_when_not_visible == TimerShouldFireWhenNotVisible::No
&& it.value->owner
&& !it.value->owner->is_visible_for_timer_purposes()) {
continue;
}
#ifdef CEVENTLOOP_DEBUG
dbg() << "CEventLoop: Timer " << timer.timer_id << " has expired, sending CTimerEvent to " << timer.owner;
#endif
post_event(*timer.owner, make<CTimerEvent>(timer.timer_id));
if (timer.should_reload) {
timer.reload(now);
} else {
// FIXME: Support removing expired timers that don't want to reload.
ASSERT_NOT_REACHED();
}
}
if (!marked_fd_count)
return;
for (auto& notifier : *s_notifiers) {
if (FD_ISSET(notifier->fd(), &rfds)) {
if (notifier->on_ready_to_read)
post_event(*notifier, make<CNotifierReadEvent>(notifier->fd()));
}
if (FD_ISSET(notifier->fd(), &wfds)) {
if (notifier->on_ready_to_write)
post_event(*notifier, make<CNotifierWriteEvent>(notifier->fd()));
}
}
}
bool CEventLoop::EventLoopTimer::has_expired(const timeval& now) const
{
return now.tv_sec > fire_time.tv_sec || (now.tv_sec == fire_time.tv_sec && now.tv_usec >= fire_time.tv_usec);
}
void CEventLoop::EventLoopTimer::reload(const timeval& now)
{
fire_time = now;
fire_time.tv_sec += interval / 1000;
fire_time.tv_usec += (interval % 1000) * 1000;
}
void CEventLoop::get_next_timer_expiration(timeval& soonest)
{
ASSERT(!s_timers->is_empty());
bool has_checked_any = false;
for (auto& it : *s_timers) {
auto& fire_time = it.value->fire_time;
if (it.value->fire_when_not_visible == TimerShouldFireWhenNotVisible::No
&& it.value->owner
&& !it.value->owner->is_visible_for_timer_purposes()) {
continue;
}
if (!has_checked_any || fire_time.tv_sec < soonest.tv_sec || (fire_time.tv_sec == soonest.tv_sec && fire_time.tv_usec < soonest.tv_usec))
soonest = fire_time;
has_checked_any = true;
}
}
int CEventLoop::register_timer(CObject& object, int milliseconds, bool should_reload, TimerShouldFireWhenNotVisible fire_when_not_visible)
{
ASSERT(milliseconds >= 0);
auto timer = make<EventLoopTimer>();
timer->owner = object.make_weak_ptr();
timer->interval = milliseconds;
timeval now;
gettimeofday(&now, nullptr);
timer->reload(now);
timer->should_reload = should_reload;
timer->fire_when_not_visible = fire_when_not_visible;
int timer_id = ++s_next_timer_id; // FIXME: This will eventually wrap around.
ASSERT(timer_id); // FIXME: Aforementioned wraparound.
timer->timer_id = timer_id;
s_timers->set(timer_id, move(timer));
return timer_id;
}
bool CEventLoop::unregister_timer(int timer_id)
{
auto it = s_timers->find(timer_id);
if (it == s_timers->end())
return false;
s_timers->remove(it);
return true;
}
void CEventLoop::register_notifier(Badge<CNotifier>, CNotifier& notifier)
{
s_notifiers->set(&notifier);
}
void CEventLoop::unregister_notifier(Badge<CNotifier>, CNotifier& notifier)
{
s_notifiers->remove(&notifier);
}
void CEventLoop::wake()
{
char ch = '!';
int nwritten = write(s_wake_pipe_fds[1], &ch, 1);
if (nwritten < 0) {
perror("CEventLoop::wake: write");
ASSERT_NOT_REACHED();
}
}