Replace Tactility SystemEvents with new kernel implementation (#598)

TactilityKernel now has a system event API to replace the one from the Tactility subproject. It also implements several tests for it.

Tactility/Include/Tactility/SystemEvents.h

@@ -1,28 +0,0 @@
-#pragma once
-
-#include <cstdint>
-#include <functional>
-
-namespace tt::kernel {
-
-enum class SystemEvent {
-    BootSplash,
-    /** Gained IP address */
-    NetworkConnected,
-    NetworkDisconnected,
-    Time,
-};
-
-/** Value 0 mean "no subscription" */
-typedef uint32_t SystemEventSubscription;
-constexpr SystemEventSubscription NoSystemEventSubscription = 0U;
-
-typedef std::function<void(SystemEvent)> OnSystemEvent;
-
-void publishSystemEvent(SystemEvent event);
-
-SystemEventSubscription subscribeSystemEvent(SystemEvent event, OnSystemEvent handler);
-
-void unsubscribeSystemEvent(SystemEventSubscription subscription);
-
-}

Tactility/Include/Tactility/service/rtctime/RtcTimeService.h

@@ -1,21 +1,22 @@
 #pragma once
 
-#include <Tactility/SystemEvents.h>
 #include <Tactility/service/Service.h>
 
 #include <memory>
 
 struct Device;
+struct SystemEvent;
 
 namespace tt::service::rtctime {
 
 class RtcTimeService final : public Service {
 
-    kernel::SystemEventSubscription timeEventSubscription = 0;
+    bool timeEventSubscribed = false;
     Device* rtcDevice = nullptr;
 
     Device* findRtcDevice();
-    void onTimeChanged(kernel::SystemEvent event);
+    void onTimeChanged();
+    static void onTimeChangedTrampoline(struct SystemEvent* event, void* context);
 
 public:
 

Tactility/Source/SystemEvents.cpp

@@ -1,81 +0,0 @@
-#include <Tactility/CoreDefines.h>
-#include <Tactility/Mutex.h>
-#include <Tactility/SystemEvents.h>
-
-#include <tactility/check.h>
-#include <tactility/log.h>
-#include <tactility/time.h>
-
-#include <list>
-
-namespace tt::kernel {
-
-constexpr auto* TAG = "SystemEvents";
-
-struct SubscriptionData {
-    SystemEventSubscription id;
-    SystemEvent event;
-    OnSystemEvent handler;
-};
-
-static Mutex mutex;
-static SystemEventSubscription subscriptionCounter = 0;
-static std::list<SubscriptionData> subscriptions;
-
-static const char* getEventName(SystemEvent event) {
-    switch (event) {
-        using enum SystemEvent;
-        case BootSplash:
-            return TT_STRINGIFY(BootSplash);
-        case NetworkConnected:
-            return TT_STRINGIFY(NetworkConnected);
-        case NetworkDisconnected:
-            return TT_STRINGIFY(NetworkDisconnected);
-        case Time:
-            return TT_STRINGIFY(Time);
-    }
-
-    check(false); // Missing case above
-}
-
-void publishSystemEvent(SystemEvent event) {
-    LOG_I(TAG, "%s", getEventName(event));
-
-    if (mutex.lock(MAX_TICKS)) {
-        for (auto& subscription : subscriptions) {
-            if (subscription.event == event) {
-                subscription.handler(event);
-            }
-        }
-
-        mutex.unlock();
-    }
-}
-
-SystemEventSubscription subscribeSystemEvent(SystemEvent event, OnSystemEvent handler) {
-    if (mutex.lock(MAX_TICKS)) {
-        auto id = ++subscriptionCounter;
-
-        subscriptions.push_back({
-            .id = id,
-            .event = event,
-            .handler = handler
-        });
-
-        mutex.unlock();
-        return id;
-    } else {
-        check(false);
-    }
-}
-
-void unsubscribeSystemEvent(SystemEventSubscription subscription) {
-    if (mutex.lock(MAX_TICKS)) {
-        std::erase_if(subscriptions, [subscription](auto& item) {
-            return (item.id == subscription);
-        });
-        mutex.unlock();
-    }
-}
-
-}

Tactility/Source/app/boot/Boot.cpp

@@ -1,3 +1,6 @@
+#include "tactility/system_event.h"
+
+
 #include <tactility/delay.h>
 #include <tactility/drivers/backlight.h>
 #include <tactility/drivers/display.h>
@@ -6,7 +9,6 @@
 
 #include <Tactility/CpuAffinity.h>
 #include <Tactility/Paths.h>
-#include <Tactility/SystemEvents.h>
 #include <Tactility/TactilityPrivate.h>
 #include <Tactility/app/AppContext.h>
 #include <Tactility/app/AppPaths.h>
@@ -154,7 +156,7 @@ class BootApp : public App {
         // This event will likely block as other systems are initialized
         // e.g. Wi-Fi reads AP configs from SD card
         LOG_I(TAG, "Publish event");
-        kernel::publishSystemEvent(kernel::SystemEvent::BootSplash);
+        system_event_emit(KERNEL_EVENT_BOOT_COMPLETED, nullptr, 0);
 
         return 0;
     }

Tactility/Source/lvgl/Statusbar.cpp

@@ -1,6 +1,5 @@
 #define LV_USE_PRIVATE_API 1 // For actual lv_obj_t declaration
 
-#include <Tactility/SystemEvents.h>
 #include <Tactility/PubSub.h>
 #include <Tactility/RecursiveMutex.h>
 #include <Tactility/Tactility.h>
@@ -11,6 +10,7 @@
 
 #include <tactility/check.h>
 #include <tactility/log.h>
+#include <tactility/system_event.h>
 #include <tactility/time.h>
 
 #include <lvgl/fonts.h>
@@ -38,7 +38,6 @@ struct StatusbarData {
     uint8_t time_hours = 0;
     uint8_t time_minutes = 0;
     bool time_set = false;
-    kernel::SystemEventSubscription systemEventSubscription = 0;
 };
 
 static StatusbarData statusbar_data;
@@ -115,7 +114,7 @@ static void statusbar_pubsub_event(Statusbar* statusbar) {
     }
 }
 
-static void onTimeChanged(kernel::SystemEvent event) {
+static void onTimeChanged(struct SystemEvent* /*event*/, void* /*context*/) {
     if (statusbar_data.mutex.lock()) {
         statusbar_data.time_update_timer->reset(5);
         statusbar_data.mutex.unlock();
@@ -134,10 +133,7 @@ static void statusbar_constructor(const lv_obj_class_t* class_p, lv_obj_t* obj)
 
     if (!statusbar_data.time_update_timer->isRunning()) {
         statusbar_data.time_update_timer->start();
-        statusbar_data.systemEventSubscription = kernel::subscribeSystemEvent(
-            kernel::SystemEvent::Time,
-            onTimeChanged
-        );
+        system_event_subscribe(KERNEL_EVENT_TIME_CHANGED, onTimeChanged, nullptr);
     }
 }
 

Tactility/Source/network/Ntp.cpp

@@ -6,8 +6,8 @@
 #include <memory>
 
 #ifdef ESP_PLATFORM
-#include <Tactility/SystemEvents.h>
 #include <Tactility/TactilityCore.h>
+#include <tactility/system_event.h>
 #include <esp_netif_sntp.h>
 #include <esp_sntp.h>
 #endif
@@ -45,7 +45,7 @@ static void onTimeSynced(timeval* tv) {
     processedSyncEvent = true;
     esp_netif_sntp_deinit();
     storeTimeInNvs();
-    kernel::publishSystemEvent(kernel::SystemEvent::Time);
+    system_event_emit(KERNEL_EVENT_TIME_CHANGED, nullptr, 0);
 }
 
 void init() {

Tactility/Source/service/rtctime/RtcTimeService.cpp

@@ -8,6 +8,7 @@
 #include <tactility/device.h>
 #include <tactility/drivers/rtc.h>
 #include <tactility/log.h>
+#include <tactility/system_event.h>
 
 #include <cassert>
 #include <ctime>
@@ -96,15 +97,17 @@ static void writeRtcFromSystemTime(Device* rtc) {
     }
 }
 
-void RtcTimeService::onTimeChanged(kernel::SystemEvent event) {
-    if (event == kernel::SystemEvent::Time) {
-        Device* rtc = findRtcDevice();
-        if (rtc) {
-            writeRtcFromSystemTime(rtc);
-        }
+void RtcTimeService::onTimeChanged() {
+    Device* rtc = findRtcDevice();
+    if (rtc) {
+        writeRtcFromSystemTime(rtc);
     }
 }
 
+void RtcTimeService::onTimeChangedTrampoline(struct SystemEvent* /*event*/, void* context) {
+    static_cast<RtcTimeService*>(context)->onTimeChanged();
+}
+
 bool RtcTimeService::onStart(ServiceContext& serviceContext) {
     Device* rtc = findRtcDevice();
     if (!rtc) {
@@ -113,22 +116,21 @@ bool RtcTimeService::onStart(ServiceContext& serviceContext) {
     }
 
     if (setSystemTimeFromRtc(rtc)) {
-        // Publish time event so other components know time is now valid
-        kernel::publishSystemEvent(kernel::SystemEvent::Time);
+        // Emit time event so other components know time is now valid
+        system_event_emit(KERNEL_EVENT_TIME_CHANGED, nullptr, 0);
     }
 
-    timeEventSubscription = kernel::subscribeSystemEvent(
-        kernel::SystemEvent::Time,
-        [this](kernel::SystemEvent event) { onTimeChanged(event); }
-    );
+    if (system_event_subscribe(KERNEL_EVENT_TIME_CHANGED, &RtcTimeService::onTimeChangedTrampoline, this) == ERROR_NONE) {
+        timeEventSubscribed = true;
+    }
 
     return true;
 }
 
 void RtcTimeService::onStop(ServiceContext& serviceContext) {
-    if (timeEventSubscription != 0) {
-        kernel::unsubscribeSystemEvent(timeEventSubscription);
-        timeEventSubscription = 0;
+    if (timeEventSubscribed) {
+        system_event_unsubscribe(KERNEL_EVENT_TIME_CHANGED, &RtcTimeService::onTimeChangedTrampoline);
+        timeEventSubscribed = false;
     }
 
     if (rtcDevice) {

Tactility/Source/service/wifi/Wifi.cpp

@@ -3,7 +3,6 @@
 #include <Tactility/CoreDefines.h>
 #include <Tactility/LogMessages.h>
 #include <Tactility/RecursiveMutex.h>
-#include <Tactility/SystemEvents.h>
 #include <Tactility/Tactility.h>
 #include <Tactility/Timer.h>
 #include <Tactility/service/Service.h>
@@ -16,6 +15,7 @@
 #include <tactility/device.h>
 #include <tactility/drivers/wifi.h>
 #include <tactility/log.h>
+#include <tactility/system_event.h>
 #include <tactility/time.h>
 #include <tactility/wifi_auto_scan.h>
 
@@ -78,7 +78,7 @@ struct WifiServiceState {
     uint16_t scanRecordLimit = TT_WIFI_SCAN_RECORD_LIMIT;
     TickType_t lastScanTime = MAX_TICKS;
     std::unique_ptr<Timer> autoConnectTimer;
-    kernel::SystemEventSubscription bootEventSubscription = kernel::NoSystemEventSubscription;
+    bool bootEventSubscribed = false;
 };
 
 WifiServiceState state;
@@ -278,7 +278,7 @@ void onAutoConnectTimer() {
 
 // ---- Kernel driver event bridge ----
 
-void onWifiDeviceEvent(Device* /*device*/, void* /*context*/, ::WifiEvent event) {
+void onWifiDeviceEvent(Device* device, void* /*context*/, ::WifiEvent event) {
     switch (event.type) {
         case WIFI_EVENT_TYPE_SCAN_FINISHED:
             getMainDispatcher().dispatch([] { dispatchAutoConnect(); });
@@ -291,7 +291,8 @@ void onWifiDeviceEvent(Device* /*device*/, void* /*context*/, ::WifiEvent event)
                 // Resetting it on every disconnect (including deliberate ones) would
                 // let auto-connect immediately reconnect the user. Attempts that fail
                 // while pending are unpaused via WIFI_EVENT_TYPE_STATION_CONNECTION_RESULT below.
-                kernel::publishSystemEvent(kernel::SystemEvent::NetworkDisconnected);
+                NetworkDisconnectedEvent disconnected_event = { .device = device };
+                system_event_emit(KERNEL_EVENT_NETWORK_DISCONNECTED, &disconnected_event, sizeof(disconnected_event));
             }
             break;
 
@@ -319,7 +320,6 @@ void onWifiDeviceEvent(Device* /*device*/, void* /*context*/, ::WifiEvent event)
                 if (remember && !settings::save(target)) {
                     LOG_E(TAG, "Failed to store credentials");
                 }
-                kernel::publishSystemEvent(kernel::SystemEvent::NetworkConnected);
             } else {
                 // The pending connection attempt (which paused auto-connect via connect())
                 // failed; unpause so auto-connect can try other saved APs.
@@ -492,6 +492,10 @@ std::string getIp() {
 
 namespace {
 
+void onBootCompleted(struct SystemEvent* /*event*/, void* /*context*/) {
+    bootSplashInit();
+}
+
 class WifiService final : public Service {
 
 public:
@@ -506,9 +510,9 @@ public:
             LOG_W(TAG, "No WiFi device found");
         }
 
-        state.bootEventSubscription = kernel::subscribeSystemEvent(kernel::SystemEvent::BootSplash, [](auto) {
-            bootSplashInit();
-        });
+        if (system_event_subscribe(KERNEL_EVENT_BOOT_COMPLETED, onBootCompleted, nullptr) == ERROR_NONE) {
+            state.bootEventSubscribed = true;
+        }
 
         auto timer_interval = std::min(2000, AUTO_SCAN_INTERVAL);
         state.autoConnectTimer = std::make_unique<Timer>(Timer::Type::Periodic, timer_interval, [] { onAutoConnectTimer(); });
@@ -526,8 +530,10 @@ public:
         state.autoConnectTimer->stop();
         state.autoConnectTimer = nullptr; // Must release as it holds a reference via its callback.
 
-        kernel::unsubscribeSystemEvent(state.bootEventSubscription);
-        state.bootEventSubscription = kernel::NoSystemEventSubscription;
+        if (state.bootEventSubscribed) {
+            system_event_unsubscribe(KERNEL_EVENT_BOOT_COMPLETED, onBootCompleted);
+            state.bootEventSubscribed = false;
+        }
 
         if (state.device != nullptr && device_is_ready(state.device)) {
             wifi_remove_event_callback(state.device, onWifiDeviceEvent);

Tactility/Source/settings/time.cpp

@@ -1,9 +1,10 @@
 #include <Tactility/settings/Time.h>
 
-#include <Tactility/SystemEvents.h>
 #include <Tactility/Preferences.h>
 #include <Tactility/settings/SystemSettings.h>
 
+#include <tactility/system_event.h>
+
 #ifdef ESP_PLATFORM
 #include <ctime>
 #endif
@@ -36,7 +37,7 @@ void setTimeZone(const std::string& name, const std::string& code) {
     tzset();
 #endif
 
-    kernel::publishSystemEvent(kernel::SystemEvent::Time);
+    system_event_emit(KERNEL_EVENT_TIME_CHANGED, nullptr, 0);
 }
 
 std::string getTimeZoneName() {