From 53dd407ae357550407227dc3156da0d37840ff02 Mon Sep 17 00:00:00 2001
From: psucien <bad_cast@protonmail.com>
Date: Tue, 18 Jun 2024 10:10:27 +0200
Subject: [PATCH] kernel: event_queue: initial `sceKernelAddHRTimerEvent` added

---
 src/core/libraries/kernel/event_queue.cpp  | 14 +++++++++-----
 src/core/libraries/kernel/event_queue.h    | 10 ++++++++++
 src/core/libraries/kernel/event_queues.cpp | 22 ++++++++++++++++++++++
 src/core/libraries/kernel/event_queues.h   |  1 +
 src/core/libraries/kernel/libkernel.cpp    |  1 +
 5 files changed, 43 insertions(+), 5 deletions(-)

diff --git a/src/core/libraries/kernel/event_queue.cpp b/src/core/libraries/kernel/event_queue.cpp
index 81ccda8a..2a0cb3ef 100644
--- a/src/core/libraries/kernel/event_queue.cpp
+++ b/src/core/libraries/kernel/event_queue.cpp
@@ -8,15 +8,19 @@ namespace Libraries::Kernel {
 
 EqueueInternal::~EqueueInternal() = default;
 
-int EqueueInternal::addEvent(const EqueueEvent& event) {
+int EqueueInternal::addEvent(EqueueEvent& event) {
     std::scoped_lock lock{m_mutex};
 
-    ASSERT(!event.IsTriggered());
+    const auto start_clock = std::chrono::high_resolution_clock::now();
+    event.filter.added_time_us =
+        std::chrono::time_point_cast<std::chrono::microseconds>(start_clock);
 
     const auto& it = std::ranges::find(m_events, event);
-    ASSERT(it == m_events.cend()); // TODO: update event if found
-
-    m_events.push_back(event);
+    if (it != m_events.cend()) {
+        *it = event;
+    } else {
+        m_events.push_back(event);
+    }
     return 0;
 }
 
diff --git a/src/core/libraries/kernel/event_queue.h b/src/core/libraries/kernel/event_queue.h
index 6abcb33c..25f4c453 100644
--- a/src/core/libraries/kernel/event_queue.h
+++ b/src/core/libraries/kernel/event_queue.h
@@ -70,6 +70,7 @@ struct SceKernelEvent {
 
 struct Filter {
     void* data = nullptr;
+    std::chrono::time_point<std::chrono::steady_clock, std::chrono::microseconds> added_time_us;
 };
 
 struct EqueueEvent {
@@ -89,6 +90,15 @@ struct EqueueEvent {
     }
 
     bool IsTriggered() const {
+        if (event.filter == Kernel::EVFILT_HRTIMER) {
+            // For HR timers we don't want to waste time on spawning waiters. Instead, we will check
+            // for time out condition every time caller fetches the event status.
+            const auto now_clock = std::chrono::high_resolution_clock::now();
+            const auto now_time_us =
+                std::chrono::time_point_cast<std::chrono::microseconds>(now_clock);
+            const auto delta = (now_time_us - filter.added_time_us).count();
+            return (s64(event.data) - delta) <= 0;
+        }
         return is_triggered;
     }
 
diff --git a/src/core/libraries/kernel/event_queues.cpp b/src/core/libraries/kernel/event_queues.cpp
index 3b65af0d..e93c77fa 100644
--- a/src/core/libraries/kernel/event_queues.cpp
+++ b/src/core/libraries/kernel/event_queues.cpp
@@ -113,6 +113,28 @@ int PS4_SYSV_ABI sceKernelAddUserEventEdge(SceKernelEqueue eq, int id) {
     return eq->addEvent(event);
 }
 
+s32 PS4_SYSV_ABI sceKernelAddHRTimerEvent(SceKernelEqueue eq, int id, timespec* ts, void* udata) {
+    if (eq == nullptr) {
+        return ORBIS_KERNEL_ERROR_EBADF;
+    }
+
+    if (ts->tv_sec > 100 || ts->tv_nsec < 100'000) {
+        return ORBIS_KERNEL_ERROR_EINVAL;
+    }
+    ASSERT(ts->tv_nsec > 1000); // assume 1us granularity
+    const auto total_us = ts->tv_sec * 1000'000 + ts->tv_nsec / 1000;
+
+    Kernel::EqueueEvent event{};
+    event.event.ident = id;
+    event.event.filter = Kernel::EVFILT_HRTIMER;
+    event.event.flags = 0x11;
+    event.event.fflags = 0;
+    event.event.data = total_us;
+    event.event.udata = udata;
+
+    return eq->addEvent(event);
+}
+
 void* PS4_SYSV_ABI sceKernelGetEventUserData(const SceKernelEvent* ev) {
     if (!ev) {
         return nullptr;
diff --git a/src/core/libraries/kernel/event_queues.h b/src/core/libraries/kernel/event_queues.h
index 8c1521b7..2549203e 100644
--- a/src/core/libraries/kernel/event_queues.h
+++ b/src/core/libraries/kernel/event_queues.h
@@ -19,5 +19,6 @@ int PS4_SYSV_ABI sceKernelTriggerUserEvent(SceKernelEqueue eq, int id, void* uda
 int PS4_SYSV_ABI sceKernelDeleteUserEvent(SceKernelEqueue eq, int id);
 int PS4_SYSV_ABI sceKernelAddUserEvent(SceKernelEqueue eq, int id);
 int PS4_SYSV_ABI sceKernelAddUserEventEdge(SceKernelEqueue eq, int id);
+s32 PS4_SYSV_ABI sceKernelAddHRTimerEvent(SceKernelEqueue eq, int id, timespec* ts, void* udata);
 
 } // namespace Libraries::Kernel
diff --git a/src/core/libraries/kernel/libkernel.cpp b/src/core/libraries/kernel/libkernel.cpp
index a4ca5901..9bc54a1d 100644
--- a/src/core/libraries/kernel/libkernel.cpp
+++ b/src/core/libraries/kernel/libkernel.cpp
@@ -324,6 +324,7 @@ void LibKernel_Register(Core::Loader::SymbolsResolver* sym) {
     LIB_FUNCTION("vz+pg2zdopI", "libkernel", 1, "libkernel", 1, 1, sceKernelGetEventUserData);
     LIB_FUNCTION("4R6-OvI2cEA", "libkernel", 1, "libkernel", 1, 1, sceKernelAddUserEvent);
     LIB_FUNCTION("WDszmSbWuDk", "libkernel", 1, "libkernel", 1, 1, sceKernelAddUserEventEdge);
+    LIB_FUNCTION("R74tt43xP6k", "libkernel", 1, "libkernel", 1, 1, sceKernelAddHRTimerEvent);
     LIB_FUNCTION("F6e0kwo4cnk", "libkernel", 1, "libkernel", 1, 1, sceKernelTriggerUserEvent);
     LIB_FUNCTION("LJDwdSNTnDg", "libkernel", 1, "libkernel", 1, 1, sceKernelDeleteUserEvent);