Don't use semaphores for lock state tracking

applications/services/desktop/desktop.c

@@ -417,7 +417,7 @@ void desktop_unlock(Desktop* desktop) {
 
     view_port_enabled_set(desktop->lock_icon_viewport, false);
     Gui* gui = furi_record_open(RECORD_GUI);
-    gui_remove_lockdown(gui);
+    gui_set_lockdown(gui, false);
     furi_record_close(RECORD_GUI);
     desktop_view_locked_unlock(desktop->locked_view);
     scene_manager_search_and_switch_to_previous_scene(desktop->scene_manager, DesktopSceneMain);

applications/services/desktop/scenes/desktop_scene_locked.c

@@ -45,7 +45,7 @@ void desktop_scene_locked_on_enter(void* context) {
     if(state == DesktopSceneLockedStateFirstEnter) {
         view_port_enabled_set(desktop->lock_icon_viewport, true);
         Gui* gui = furi_record_open(RECORD_GUI);
-        gui_set_lockdown(gui);
+        gui_set_lockdown(gui, true);
         furi_record_close(RECORD_GUI);
 
         if(desktop_pin_code_is_set()) {

applications/services/gui/gui.c

@@ -484,33 +484,32 @@ size_t gui_get_framebuffer_size(const Gui* gui) {
     return canvas_get_buffer_size(gui->canvas);
 }
 
-void gui_set_lockdown(Gui* gui) {
+void gui_set_lockdown(Gui* gui, bool lockdown) {
     furi_check(gui);
 
     gui_lock(gui);
-    FURI_LOG_D(TAG, "Releasing lockdown semaphore");
+    gui->lockdown = lockdown;
-    furi_semaphore_release(gui->unlock);
     gui_unlock(gui);
 
     // Request redraw
     gui_update(gui);
 }
 
-void gui_remove_lockdown(Gui* gui) {
+void gui_set_lockdown_inhibit(Gui* gui, bool inhibit) {
     furi_check(gui);
-    FURI_LOG_D(TAG, "Acquiring lockdown semaphore");
 
     gui_lock(gui);
-    if(furi_semaphore_acquire(gui->unlock, 1000) != FuriStatusOk) {
+    gui->lockdown_inhibit = inhibit;
-        furi_crash("Could not acquire lockdown semaphore");
-    }
     gui_unlock(gui);
+
+    // Request redraw
+    gui_update(gui);
 }
 
 bool gui_is_lockdown(const Gui* gui) {
     furi_check(gui);
 
-    return furi_semaphore_get_count(gui->unlock) == 0;
+    return gui->lockdown && !gui->lockdown_inhibit;
 }
 
 Canvas* gui_direct_draw_acquire(Gui* gui) {
@@ -547,8 +546,6 @@ Gui* gui_alloc(void) {
     gui->thread_id = furi_thread_get_current_id();
     // Allocate mutex
     gui->mutex = furi_mutex_alloc(FuriMutexTypeNormal);
-    // Semaphore for the lockdown state
-    gui->unlock = furi_semaphore_alloc(2, 1);
 
     // Layers
     for(size_t i = 0; i < GuiLayerMAX; i++) {

applications/services/gui/gui.h

@@ -106,14 +106,19 @@ size_t gui_get_framebuffer_size(const Gui* gui);
  * This feature prevents services from showing sensitive information when flipper is locked.
  *
  * @param      gui       Gui instance
+ * @param      lockdown  true to enable lockdown mode
  */
-void gui_set_lockdown(Gui* gui);
+void gui_set_lockdown(Gui* gui, bool lockdown);
 
-/** Disable lockdown mode
+/** Inhibit lockdown mode
- *
+ * 
+ * Lockdown mode can be inhibited by calling this function with inhibit set to true.
+ * This is used to show information even when flipper is locked.
+ * 
  * @param      gui       Gui instance
+ * @param      inhibit   true to inhibit lockdown mode
  */
-void gui_remove_lockdown(Gui* gui);
+void gui_set_lockdown_inhibit(Gui* gui, bool inhibit);
 
 /** Check if Gui is in lockdown mode
  * 

applications/services/gui/gui_i.h

@@ -48,9 +48,10 @@ struct Gui {
     // Thread and lock
     FuriThreadId thread_id;
     FuriMutex* mutex;
-    FuriSemaphore* unlock;
 
     // Layers and Canvas
+    bool lockdown;
+    bool lockdown_inhibit;
     bool direct_draw;
     ViewPortArray_t layers[GuiLayerMAX];
     Canvas* canvas;

applications/settings/clock_settings/clock_settings_alarm.c

@@ -112,7 +112,7 @@ int32_t clock_settings_alarm(void* p) {
 
     // Register view port in GUI
     Gui* gui = furi_record_open(RECORD_GUI);
-    gui_remove_lockdown(gui);
+    gui_set_lockdown_inhibit(gui, true);
     gui_add_view_port(gui, view_port, GuiLayerFullscreen);
 
     NotificationApp* notification = furi_record_open(RECORD_NOTIFICATION);
@@ -139,7 +139,7 @@ int32_t clock_settings_alarm(void* p) {
                     model.is_snooze = true;
                     model.alarm_start = model.snooze_until; // For correct timeout behavior
                     view_port_enabled_set(view_port, false);
-                    gui_set_lockdown(gui);
+                    gui_set_lockdown_inhibit(gui, false);
                 } else {
                     running = false;
                 }
@@ -149,7 +149,7 @@ int32_t clock_settings_alarm(void* p) {
             if(datetime_datetime_to_timestamp(&model.now) >=
                datetime_datetime_to_timestamp(&model.snooze_until)) {
                 view_port_enabled_set(view_port, true);
-                gui_remove_lockdown(gui);
+                gui_set_lockdown_inhibit(gui, true);
 
                 model.is_snooze = false;
             }
@@ -174,7 +174,7 @@ int32_t clock_settings_alarm(void* p) {
     furi_record_close(RECORD_NOTIFICATION);
 
     view_port_enabled_set(view_port, false);
-    gui_set_lockdown(gui);
+    gui_set_lockdown_inhibit(gui, false);
     gui_remove_view_port(gui, view_port);
     view_port_free(view_port);
     furi_message_queue_free(event_queue);

targets/f7/api_symbols.csv

@@ -1,5 +1,5 @@
 entry,status,name,type,params
-Version,+,79.2,,
+Version,+,80.0,,
 Header,+,applications/drivers/subghz/cc1101_ext/cc1101_ext_interconnect.h,,
 Header,+,applications/services/bt/bt_service/bt.h,,
 Header,+,applications/services/bt/bt_service/bt_keys_storage.h,,
@@ -1957,9 +1957,9 @@ Function,+,gui_direct_draw_release,void,Gui*
 Function,+,gui_get_framebuffer_size,size_t,const Gui*
 Function,+,gui_is_lockdown,_Bool,const Gui*
 Function,+,gui_remove_framebuffer_callback,void,"Gui*, GuiCanvasCommitCallback, void*"
-Function,+,gui_remove_lockdown,void,Gui*
 Function,+,gui_remove_view_port,void,"Gui*, ViewPort*"
-Function,+,gui_set_lockdown,void,Gui*
+Function,+,gui_set_lockdown,void,"Gui*, _Bool"
+Function,+,gui_set_lockdown_inhibit,void,"Gui*, _Bool"
 Function,-,gui_view_port_send_to_back,void,"Gui*, ViewPort*"
 Function,+,gui_view_port_send_to_front,void,"Gui*, ViewPort*"
 Function,-,hci_send_req,int,"hci_request*, uint8_t"
@@ -2940,9 +2940,9 @@ Function,+,pipe_install_as_stdio,void,PipeSide*
 Function,+,pipe_receive,size_t,"PipeSide*, void*, size_t, FuriWait"
 Function,+,pipe_role,PipeRole,PipeSide*
 Function,+,pipe_send,size_t,"PipeSide*, const void*, size_t, FuriWait"
+Function,+,pipe_set_broken_callback,void,"PipeSide*, PipeSideBrokenCallback, FuriEventLoopEvent"
 Function,+,pipe_set_callback_context,void,"PipeSide*, void*"
 Function,+,pipe_set_data_arrived_callback,void,"PipeSide*, PipeSideDataArrivedCallback, FuriEventLoopEvent"
-Function,+,pipe_set_broken_callback,void,"PipeSide*, PipeSideBrokenCallback, FuriEventLoopEvent"
 Function,+,pipe_set_space_freed_callback,void,"PipeSide*, PipeSideSpaceFreedCallback, FuriEventLoopEvent"
 Function,+,pipe_spaces_available,size_t,PipeSide*
 Function,+,pipe_state,PipeState,PipeSide*