handle quit/close events across SDL and wx sides including asking to save changes; refactor to remove old unused event loop code

src/E2wxApp.cpp

@@ -70,8 +70,9 @@ EmuTimer::EmuTimer(Emulator *e) : wxTimer(), emu(e) {
 EmuTimer::~EmuTimer() {
 }
 
+#define EXPECTED_MS 50 // see CHECK_EVERY_CYCLE in Emulator.cpp
 void EmuTimer::begin() {
-    this->Start(50); // TODO: EXPECTED_MS from Emulator
+    this->Start(EXPECTED_MS);
 }
 
 void EmuTimer::Notify() {
@@ -83,7 +84,10 @@ void EmuTimer::Notify() {
 
 E2wxApp::E2wxApp() :
     id(wxSTRINGIZE(PROJECT_VENDOR) "." wxSTRINGIZE(PROJECT_NAME)),
-    version(wxSTRINGIZE(PROJECT_VERSION)) {
+    version(wxSTRINGIZE(PROJECT_VERSION)),
+    frame(nullptr),
+    emu(nullptr),
+    emu_timer(nullptr) {
 }
 
 E2wxApp::~E2wxApp() {
@@ -169,7 +173,7 @@ bool E2wxApp::OnInit() {
 
 
 
-    E2wxFrame *frame = new E2wxFrame();
+    frame = new E2wxFrame();
     frame->DoInit();
     frame->Show();
 
@@ -184,12 +188,26 @@ bool E2wxApp::OnInit() {
 
 
 
+bool E2wxApp::CloseMainFrame() {
+    bool r = false;
+    if (this->frame) {
+        if (this->frame->Close(false)) {
+            delete this->frame;
+            this->frame = nullptr;
+            r = true;
+        }
+    }
+    return r;
+}
+
 int E2wxApp::OnExit() {
     if (this->emu_timer) {
         delete this->emu_timer;
+        this->emu_timer = nullptr;
     }
     if (this->emu) {
         delete this->emu;
+        this->emu = nullptr;
     }
     return 0;
 }
@@ -308,10 +326,26 @@ void E2wxApp::InitBoostLog() {
 
 
 void E2wxApp::StartEmulator() {
+    if (this->emu_timer) {
+        delete this->emu_timer;
+    }
+    if (this->emu) {
+        delete this->emu;
+    }
+
     this->emu = new Emulator();
-    E2Config cfg(this->arg_configfile, this->opt_config_from_prefs_only);
+    E2Config cfg{this->arg_configfile, this->opt_config_from_prefs_only};
     this->emu->config(cfg);
     this->emu->init();
-    this->emu_timer = new EmuTimer(this->emu);
+
+    this->emu_timer = new EmuTimer{this->emu};
     this->emu_timer->begin();
 }
+
+bool E2wxApp::EnsureCanQuit() {
+    bool ok = true;
+    if (this->emu) {
+        ok = this->emu->isSafeToQuit();
+    }
+    return ok;
+}

src/E2wxApp.h

@@ -32,6 +32,7 @@
 
 
 
+class E2wxFrame;
 class Emulator;
 
 
@@ -60,6 +61,7 @@ class E2wxApp : public wxApp {
     std::filesystem::path docsdir;
     std::filesystem::path arg_configfile;
     bool opt_config_from_prefs_only;
+    E2wxFrame *frame;
     EmuTimer *emu_timer;
     Emulator *emu;
 
@@ -79,6 +81,9 @@ public:
     const std::filesystem::path GetConfigDir() const;
     const std::filesystem::path GetDocumentsDir() const;
 
+    bool CloseMainFrame();
+    bool EnsureCanQuit();
+
     virtual bool OnInit() override;
     virtual int OnExit() override;
     virtual void OnFatalException() override;

src/E2wxFrame.cpp

@@ -24,8 +24,11 @@
 #include "gui.h"
 #include <wx/menu.h>
 #include <wx/msgdlg.h>
+#include <wx/event.h>
 #include <wx/persist/toplevel.h>
 
+
+
 enum E2MenuID {
     ID_MENUITEM_POWER = wxID_HIGHEST+1
 };
@@ -35,6 +38,7 @@ wxBEGIN_EVENT_TABLE(E2wxFrame, wxFrame)
     EVT_MENU(wxID_PREFERENCES, E2wxFrame::OnPreferences)
     EVT_MENU(wxID_ABOUT, E2wxFrame::OnAbout)
     EVT_MENU(ID_MENUITEM_POWER, E2wxFrame::OnTogglePower)
+    EVT_CLOSE(E2wxFrame::HandleUserQuitRequest)
 wxEND_EVENT_TABLE()
 
 
@@ -84,7 +88,7 @@ void E2wxFrame::InitStatusBar() {
 
 
 void E2wxFrame::OnExit(wxCommandEvent& event) {
-    Close(true);
+    Close(false);
 }
 
 void E2wxFrame::OnAbout(wxCommandEvent& event) {
@@ -109,3 +113,12 @@ void E2wxFrame::OnPreferences(wxCommandEvent& event) {
 void E2wxFrame::OnTogglePower(wxCommandEvent& event) {
     GUI::queueTogglePower();
 }
+
+void E2wxFrame::HandleUserQuitRequest(wxCloseEvent& event) {
+    // TODO how to handle event.CanVeto() ? I'd like to auto-save everything
+    if (wxGetApp().EnsureCanQuit()) {
+        event.Skip();
+    } else {
+        event.Veto();
+    }
+}

src/E2wxFrame.h

@@ -37,6 +37,7 @@ private:
     void OnPreferences(wxCommandEvent& event);
     void OnAbout(wxCommandEvent& event);
     void OnTogglePower(wxCommandEvent& event);
+    void HandleUserQuitRequest(wxCloseEvent& event);
 
     void InitMenuBar();
     void InitStatusBar();

src/emulator.cpp

@@ -16,6 +16,7 @@
     along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 #include "emulator.h"
+#include "E2wxApp.h"
 #include "e2config.h"
 #include "e2command.h"
 #include "e2const.h"
@@ -65,7 +66,6 @@ void Emulator::powerOnComputer() {
 }
 
 void Emulator::powerOffComputer() {
-    // TODO Need to ask user if OK to lose any unsaved changes to disks
     this->apple2.powerOff();
     this->screenImage.drawPower(false);
     this->display.setNoise(true);
@@ -85,26 +85,10 @@ void Emulator::init() {
     this->display.powerOn(true);
 }
 
-// How many emulation ticks between asking SDL if there is any new input
-// from the user or other GUI events.
-// This is also how often we shall update the estimate of the emulator's
-// actual speed performance
-// When the CPU is the object being ticked (each tick is a CPU cycle), then
-// this is 20.04378892 Hz in emulated seconds time
-#define CHECK_EVERY_CYCLE 51024
-#define CHECK_CYCLES_K 51024000
-#define EXPECTED_MS 50
 
 // U.A.2 p. 7-13: REPT key repeats at 10Hz.
 static const int CYCLES_PER_REPT(E2Const::AVG_CPU_HZ / 10);
 
-
-
-
-
-
-
-
 // If the Apple ][ keyboard repeat is on (the REPT key is
 // down)...
 void Emulator::handleRepeatKey() {
@@ -134,7 +118,9 @@ void Emulator::handleAnyPendingEvents() {
         switch (event.type) {
             case SDL_QUIT:
                 // If SDL is going away...
-                quitIfSafe();
+                // could be due to user closing the SDL window, pressing cmd-Q on Mac,
+                // ctrl-C from the command line on Linux, process being killed, etc.
+                handleUserQuitRequest();
             break;
             case SDL_KEYDOWN:
                 // If we're collecting a command line for changing any
@@ -145,6 +131,7 @@ void Emulator::handleAnyPendingEvents() {
                     // ...else we're collecting keypresses for the keyboard
                     // emulation (and thus the Apple ][ emulation itself)
                     dispatchKeypress(event.key);
+                    // People who have too many press-releases should be referred to as "keyboards"
             break;
             case SDL_KEYUP:
                 // If we're collecting a command line for changing any
@@ -166,54 +153,15 @@ void Emulator::handleAnyPendingEvents() {
 
 
 
+// How many emulation ticks between asking SDL if there is any new input
+// from the user or other GUI events.
+// This is also how often we shall update the estimate of the emulator's
+// actual speed performance
+// When the CPU is the object being ticked (each tick is a CPU cycle), then
+// this is 20.04378892 Hz in emulated seconds time
+#define CHECK_EVERY_CYCLE 51024
+
 // The core of this Apple
-int Emulator::run() {
-    // While the user still wants to run this emulation...
-    while (!this->quit) {
-        tick();
-    }
-    return 0;
-}
-
-
-
-
-void Emulator::tick() {
-    if (this->timable) {
-        this->timable->tick(); // this runs the emulator!
-        handleRepeatKey();
-    }
-
-    // People who have too many press releases should be referred to as
-    // keyboards
-
-    if (CHECK_EVERY_CYCLE <= ++this->skip) {
-        // ...then it's time to drain away any piled-up user interaction
-        // events that SDL has stored up for us
-        // Reload the skip quantity
-        this->skip = 0;
-
-        handleAnyPendingEvents();
-
-        // If we're trying to run as slow as a real Apple ][...
-        if (!this->fhyper.isHyper()) {
-            const int delta_ms = EXPECTED_MS - (SDL_GetTicks() - this->prev_ms);
-            if (0 < delta_ms && delta_ms <= EXPECTED_MS) {
-                SDL_Delay(delta_ms);
-            }
-
-        }
-
-        // Display the current estimate of the emulator's actual speed
-        // performance
-        this->screenImage.displayHz(CHECK_CYCLES_K / (SDL_GetTicks() - this->prev_ms));
-
-        this->prev_ms = SDL_GetTicks();
-    }
-}
-
-
-
 void Emulator::tick50ms() {
     if (this->timable) {
         for (int i = 0; i < CHECK_EVERY_CYCLE; ++i) {
@@ -222,7 +170,7 @@ void Emulator::tick50ms() {
         }
     }
     handleAnyPendingEvents();
-    this->screenImage.displayHz(CHECK_CYCLES_K / (SDL_GetTicks() - this->prev_ms));
+    this->screenImage.displayHz((1000*CHECK_EVERY_CYCLE)/(SDL_GetTicks() - this->prev_ms));
     this->prev_ms = SDL_GetTicks();
     // TODO: how to check this->quit ?
 }
@@ -413,7 +361,7 @@ void Emulator::dispatchKeypress(const SDL_KeyboardEvent& keyEvent) {
         return;
     }// ...else exit the entire emulation
     else if (sym == SDLK_F9) {
-        quitIfSafe();
+        handleUserQuitRequest();
         return;
     }// ...else save a screen shot
     else if (sym == SDLK_F8) {
@@ -495,7 +443,10 @@ static int askSave() {
 }
 
 bool Emulator::isSafeToQuit() {
+    this->screenImage.exitFullScreen();
+
     if (!this->apple2.cassetteOut.eject()) {
+        // TODO does this handle the case where we fail to save?
         return false;
     }
 
@@ -512,14 +463,17 @@ bool Emulator::isSafeToQuit() {
     if (resp == wxID_YES) {
         this->apple2.slts.save(0);
         this->apple2.slts.save(1);
+        // TODO handle case where we fail to save,
+        // in which case we should alert the user,
+        // and return false
     }
 
     return true;
 }
 
-void Emulator::quitIfSafe() {
+// we come here due to F9 or SQL_Quit event
-    this->screenImage.exitFullScreen();
+void Emulator::handleUserQuitRequest() {
-    if (isSafeToQuit()) {
+    wxGetApp().CloseMainFrame();
-        this->quit = true;
+    // wxWidgets will then call us back with isSafeToQuit, and if so will exit the application
-    }
+    // (note wxWidgets will also need to call us back when it gets it's own quit requests)
 }

src/emulator.h

@@ -32,8 +32,7 @@
 class Timable;
 class E2Config;
 
-class Emulator
+class Emulator {
-{
     PaddleButtonStates paddleButtonStates;
     KeypressQueue keypresses;
 
@@ -58,16 +57,14 @@ class Emulator
     bool pendingCommandExit;
     std::string cmdline;
 
-    void tick();
-
     void dispatchKeypress(const SDL_KeyboardEvent& keyEvent);
     void dispatchKeyUp(const SDL_KeyboardEvent& keyEvent);
     void cmdKey(const SDL_KeyboardEvent& keyEvent);
     void processCommand();
-    bool isSafeToQuit();
 
     void handleRepeatKey();
     void handleAnyPendingEvents();
+    void handleUserQuitRequest();
 
 public:
     Emulator();
@@ -75,15 +72,14 @@ public:
 
     void config(E2Config& cfg);
 
-    virtual void init();
+    void init();
 
     void powerOnComputer();
     void powerOffComputer();
     void toggleComputerPower();
     void cycleDisplayType();
-    void quitIfSafe();
+    bool isSafeToQuit();
 
-    virtual int run();
     void tick50ms();
 };