Cleanup and improvements (#194)

- Lots of changes for migrating C code to C++
- Improved `Lockable` in several ways like adding `withLock()` (+ tests)
- Improved `Semaphore` a bit for improved readability, and also added some tests
- Upgrade Linux machine in GitHub Actions so that we can compile with a newer GCC
- Simplification of WiFi connection
- Updated funding options
- (and more)

Tactility/Private/app/AppInstance.h

@@ -10,13 +10,13 @@
 
 namespace tt::app {
 
-typedef enum {
-    StateInitial, // App is being activated in loader
-    StateStarted, // App is in memory
-    StateShowing, // App view is created
-    StateHiding,  // App view is destroyed
-    StateStopped  // App is not in memory
-} State;
+enum class State {
+    Initial, // App is being activated in loader
+    Started, // App is in memory
+    Showing, // App view is created
+    Hiding,  // App view is destroyed
+    Stopped  // App is not in memory
+};
 
 /**
  * Thread-safe app instance.
@@ -27,7 +27,7 @@ private:
 
     Mutex mutex = Mutex(Mutex::Type::Normal);
     const std::shared_ptr<AppManifest> manifest;
-    State state = StateInitial;
+    State state = State::Initial;
     Flags flags = { .showStatusbar = true };
     /** @brief Optional parameters to start the app with
      * When these are stored in the app struct, the struct takes ownership.

Tactility/Private/app/files/State.h

@@ -41,13 +41,11 @@ public:
     bool setEntriesForChildPath(const std::string& child_path);
     bool setEntriesForPath(const std::string& path);
 
-    const std::vector<dirent>& lockEntries() const {
-        mutex.lock();
-        return dir_entries;
-    }
-
-    void unlockEntries() {
-        mutex.unlock();
+    template <std::invocable<const std::vector<dirent> &> Func>
+    void withEntries(Func&& onEntries) const {
+        mutex.withLock([&]() {
+            std::invoke(std::forward<Func>(onEntries), dir_entries);
+        });
     }
 
     bool getDirent(uint32_t index, dirent& dirent);

Tactility/Private/app/wificonnect/State.h

@@ -20,9 +20,6 @@ public:
     void setConnectionError(bool error);
     bool hasConnectionError() const;
 
-    const service::wifi::settings::WifiApSettings& lockApSettings();
-    void unlockApSettings();
-
     void setApSettings(const service::wifi::settings::WifiApSettings* newSettings);
 
     void setConnecting(bool isConnecting);

Tactility/Private/app/wifimanage/State.h

@@ -30,8 +30,12 @@ public:
 
     void updateApRecords();
 
-    const std::vector<service::wifi::ApRecord>& lockApRecords() const;
-    void unlockApRecords() const;
+    template <std::invocable<const std::vector<service::wifi::ApRecord>&> Func>
+    void withApRecords(Func&& onApRecords) const {
+        mutex.withLock([&]() {
+            std::invoke(std::forward<Func>(onApRecords), apRecords);
+        });
+    }
 
     void setConnectSsid(const std::string& ssid);
     std::string getConnectSsid() const;