xdg-shell: queue state updates for toplevel (#14227)

ref https://github.com/hyprwm/Hyprland/discussions/14224

2 files changed, 48 insertions, 9 deletions

diff --git a/src/managers/eventLoop/EventLoopManager.cpp b/src/managers/eventLoop/EventLoopManager.cpp
index 03a8d7c9..6c661a6f 100644
--- a/src/managers/eventLoop/EventLoopManager.cpp
+++ b/src/managers/eventLoop/EventLoopManager.cpp
@@ -16,6 +16,17 @@ using namespace Hyprutils::OS;
 
 #define TIMESPEC_NSEC_PER_SEC 1000000000L
 
+static uint64_t LAST_DO_LATER_SEQ = 1;
+
+SEventLoopDoLaterLock::SEventLoopDoLaterLock(uint64_t seq_) : seq(seq_) {
+    ;
+}
+
+SEventLoopDoLaterLock::~SEventLoopDoLaterLock() {
+    if (g_pEventLoopManager && seq > 0)
+        g_pEventLoopManager->removeDoLater(seq);
+}
+
 CEventLoopManager::CEventLoopManager(wl_display* display, wl_event_loop* wlEventLoop) {
     m_timers.timerfd  = CFileDescriptor{timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC)};
     m_wayland.loop    = wlEventLoop;
@@ -201,11 +212,13 @@ void CEventLoopManager::nudgeTimers() {
     timerfd_settime(m_timers.timerfd.get(), TFD_TIMER_ABSTIME, &ts, nullptr);
 }
 
-void CEventLoopManager::doLater(const std::function<void()>& fn) {
-    m_idle.fns.emplace_back(fn);
+uint64_t CEventLoopManager::doLater(const std::function<void()>& fn) {
+    const uint64_t NEW_SEQ = ++LAST_DO_LATER_SEQ;
+
+    m_idle.fns.emplace_back(std::make_pair<>(NEW_SEQ, fn));
 
     if (m_idle.eventSource)
-        return;
+        return NEW_SEQ;
 
     m_idle.eventSource = wl_event_loop_add_idle(
         m_wayland.loop,
@@ -215,11 +228,26 @@ void CEventLoopManager::doLater(const std::function<void()>& fn) {
             IDLE->fns.clear();
             IDLE->eventSource = nullptr;
             for (auto& f : fns) {
-                if (f)
-                    f();
+                if (f.second)
+                    f.second();
             }
         },
         &m_idle);
+
+    return NEW_SEQ;
+}
+
+void CEventLoopManager::removeDoLater(uint64_t seq) {
+    std::erase_if(m_idle.fns, [&seq](const auto& e) { return e.first == seq; });
+
+    if (m_idle.fns.empty() && m_idle.eventSource) {
+        wl_event_source_remove(m_idle.eventSource);
+        m_idle.eventSource = nullptr;
+    }
+}
+
+UP<SEventLoopDoLaterLock> CEventLoopManager::doLaterLock(const std::function<void()>& fn) {
+    return makeUnique<SEventLoopDoLaterLock>(doLater(fn));
 }
 
 void CEventLoopManager::doOnReadable(CFileDescriptor fd, std::function<void()>&& fn) {
diff --git a/src/managers/eventLoop/EventLoopManager.hpp b/src/managers/eventLoop/EventLoopManager.hpp
index 7999dc59..64673455 100644
--- a/src/managers/eventLoop/EventLoopManager.hpp
+++ b/src/managers/eventLoop/EventLoopManager.hpp
@@ -14,6 +14,13 @@ namespace Aquamarine {
     struct SPollFD;
 };
 
+struct SEventLoopDoLaterLock {
+    SEventLoopDoLaterLock(uint64_t seq);
+    ~SEventLoopDoLaterLock();
+
+    uint64_t seq = 0;
+};
+
 class CEventLoopManager {
   public:
     CEventLoopManager(wl_display* display, wl_event_loop* wlEventLoop);
@@ -30,12 +37,16 @@ class CEventLoopManager {
     // schedules a recalc of the timers
     void scheduleRecalc();
 
-    // schedules a function to run later, aka in a wayland idle event.
-    void doLater(const std::function<void()>& fn);
+    // schedules a function to run later, aka in a wayland idle event. Returns a sequence which can be used to remove it.
+    uint64_t doLater(const std::function<void()>& fn);
+    void     removeDoLater(uint64_t seq);
+
+    // automatically cleaned up doLater instance
+    [[nodiscard]] UP<SEventLoopDoLaterLock> doLaterLock(const std::function<void()>& fn);
 
     struct SIdleData {
-        wl_event_source*                   eventSource = nullptr;
-        std::vector<std::function<void()>> fns;
+        wl_event_source*                                        eventSource = nullptr;
+        std::vector<std::pair<uint64_t, std::function<void()>>> fns;
     };
 
     struct SReadableWaiter {