fix multithread logic in template app, update gpio HAL (#250)

* fix multithread logic
* more buffer for dallas id string
* update apps to use new logic
* delay_us small speedup
* add consant qualifier to gpio records and some core api
* fix some apps to use simpler method of getting gpio record
* fix ibutton app, stupid stack problem

lib/app-template/app-template.cpp

@@ -21,7 +21,7 @@ public:
 
     // state initializer
     AppExampleState() {
-        example_data = 12;
+        example_data = 0;
     }
 };
 
@@ -51,6 +51,16 @@ public:
 
 // start app
 void AppExample::run() {
+    // here we dont need to acquire or release state
+    // because before we call app_ready our application is "single threaded"
+    state.example_data = 12;
+
+    // signal that we ready to render and ipc
+    app_ready();
+
+    // from here, any data that pass in render function must be guarded
+    // by calling acquire_state and release_state
+
     AppExampleEvent event;
     while(1) {
         if(get_event(&event, 1000)) {

lib/app-template/app-template.h

@@ -6,20 +6,21 @@
 // simple app class with template variables <state, events>
 template <class TState, class TEvent> class AppTemplate {
 public:
-    AppTemplate();
-    ~AppTemplate();
-    void input_callback(InputEvent* input_event, void* ctx);
-    void draw_callback(CanvasApi* canvas, void* ctx);
-    virtual void render(CanvasApi* canvas) = 0;
     Widget* widget;
     osMessageQueueId_t event_queue;
     TState state;
     ValueMutex state_mutex;
     GuiApi* gui;
 
+    AppTemplate();
+    ~AppTemplate();
+    void input_callback(InputEvent* input_event, void* ctx);
+    void draw_callback(CanvasApi* canvas, void* ctx);
+    virtual void render(CanvasApi* canvas) = 0;
     void acquire_state(void);
     void release_state(void);
     bool get_event(TEvent* event, uint32_t timeout);
+    void app_ready(void);
     void exit(void);
     void update_gui(void);
 };
@@ -35,24 +36,15 @@ template <class TState, class TEvent> AppTemplate<TState, TEvent>::AppTemplate()
         furiac_exit(NULL);
     }
 
-    // allocate widget
-    widget = widget_alloc();
-
-    // connect widget with input callback
-    auto input_cb_ref = cbc::obtain_connector(this, &AppTemplate::input_callback);
-    widget_input_callback_set(widget, input_cb_ref, this);
-
-    // connect widget with draw callback
-    auto draw_cb_ref = cbc::obtain_connector(this, &AppTemplate::draw_callback);
-    widget_draw_callback_set(widget, draw_cb_ref, this);
-
-    // open gui and add widget
+    // open gui
     gui = (GuiApi*)furi_open("gui");
     if(gui == NULL) {
         printf("gui is not available\n");
         furiac_exit(NULL);
     }
-    gui->add_widget(gui, widget, GuiLayerFullscreen);
+
+    // allocate widget
+    widget = widget_alloc();
 }
 
 template <class TState, class TEvent> AppTemplate<TState, TEvent>::~AppTemplate() {
@@ -96,6 +88,24 @@ bool AppTemplate<TState, TEvent>::get_event(TEvent* event, uint32_t timeout) {
     return (event_status == osOK);
 }
 
+// signal that app is ready, and we can render something
+// also unblock dependent tasks
+template <class TState, class TEvent> void AppTemplate<TState, TEvent>::app_ready(void) {
+    // connect widget with input callback
+    auto input_cb_ref = cbc::obtain_connector(this, &AppTemplate::input_callback);
+    widget_input_callback_set(widget, input_cb_ref, this);
+
+    // connect widget with draw callback
+    auto draw_cb_ref = cbc::obtain_connector(this, &AppTemplate::draw_callback);
+    widget_draw_callback_set(widget, draw_cb_ref, this);
+
+    // add widget
+    gui->add_widget(gui, widget, GuiLayerFullscreen);
+
+    // signal that our app ready to work
+    furiac_ready();
+}
+
 template <class TState, class TEvent> void AppTemplate<TState, TEvent>::exit(void) {
     // TODO remove all widgets create by app
     widget_enabled_set(widget, false);