Wayland/X11 hybrid: use "bool fl_disable_wayland;" declaration.

10 files changed, 82 insertions, 123 deletions

diff --git a/src/Fl.cxx b/src/Fl.cxx
index 29f3f5839..30fe9a968 100644
--- a/src/Fl.cxx
+++ b/src/Fl.cxx
@@ -2111,14 +2111,19 @@ void fl_close_display()
   Fl::screen_driver()->close_display();
 }
 
-/** Prevent the FLTK library from using its wayland backend.
- Call this early in your main(), before fl_open_display() runs, or any window is created, or the screen is accessed.
- This function has no effect on non-Wayland platforms.
+#ifdef FL_DOXYGEN
+/** Prevent the FLTK library from using its Wayland backend and forces it to use its X11 backend.
+ Put this declaration somewhere in your code outside the body of any function  :
+ \code
+ FL_EXPORT bool fl_disable_wayland = true;
+ \endcode
+ This declaration makes sure source code developed for FLTK 1.3, including X11-specific code,
+ will build and run with FLTK 1.4 and its Wayland platform with this single source code level change.
+ This declaration has no effect on non-Wayland platforms.
+ Don't put this declaration if you want the Wayland backend to be used when it's available.
  */
-void fl_disable_wayland()
-{
-  Fl::system_driver()->disable_wayland();
-}
+FL_EXPORT bool fl_disable_wayland = true;
+#endif // FL_DOXYGEN
 
 FL_EXPORT Window fl_xid_(const Fl_Window *w) {
   Fl_X *temp = Fl_X::i(w);
diff --git a/src/Fl_System_Driver.H b/src/Fl_System_Driver.H
index 6f9ed4436..7443f7c8a 100644
--- a/src/Fl_System_Driver.H
+++ b/src/Fl_System_Driver.H
@@ -253,7 +253,6 @@ public:
   virtual void unlock_ring() {}
   virtual double wait(double);                             // must override
   virtual int ready() { return 0; }                        // must override
-  virtual void disable_wayland() {}
 };
 
 #endif // FL_SYSTEM_DRIVER_H
diff --git a/src/Fl_Text_Display.cxx b/src/Fl_Text_Display.cxx
index ed1214ae5..deaf46608 100644
--- a/src/Fl_Text_Display.cxx
+++ b/src/Fl_Text_Display.cxx
@@ -1,5 +1,5 @@
 //
-// Copyright 2001-2021 by Bill Spitzak and others.
+// Copyright 2001-2022 by Bill Spitzak and others.
 // Original code Copyright Mark Edel.  Permission to distribute under
 // the LGPL for the FLTK library granted by Mark Edel.
 //
@@ -486,6 +486,8 @@ void Fl_Text_Display::resize(int X, int Y, int W, int H) {
  */
 void Fl_Text_Display::recalc_display() {
   if (!buffer()) return;
+  // Make sure the display is opened.
+  Fl_Display_Device::display_device();
   // did we have scrollbars initially?
   unsigned int hscrollbarvisible = mHScrollBar->visible();
   unsigned int vscrollbarvisible = mVScrollBar->visible();
diff --git a/src/Fl_Widget.cxx b/src/Fl_Widget.cxx
index 185e99b58..2289dcf0b 100644
--- a/src/Fl_Widget.cxx
+++ b/src/Fl_Widget.cxx
@@ -1,7 +1,7 @@
 //
 // Base widget class for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2017 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -131,10 +131,6 @@ Fl_Widget::Fl_Widget(int X, int Y, int W, int H, const char* L) {
 
   parent_ = 0;
   if (Fl_Group::current()) Fl_Group::current()->add(this);
-  if (!fl_graphics_driver) {
-    // Make sure fl_graphics_driver is initialized. Important if we are called by a static initializer.
-    Fl_Display_Device::display_device();
-  }
 }
 
 void Fl_Widget::resize(int X, int Y, int W, int H) {
diff --git a/src/Fl_x.cxx b/src/Fl_x.cxx
index 37a9dbc71..1f1b16ba7 100644
--- a/src/Fl_x.cxx
+++ b/src/Fl_x.cxx
@@ -2562,7 +2562,8 @@ void Fl_X::make_xid(Fl_Window* win, XVisualInfo *visual, Colormap colormap)
       Fl_Window::show_iconic_ = 0;
       showit = 0;
     }
-    if (Fl_X11_Window_Driver::driver(win)->icon_->legacy_icon) {
+    if (Fl_X11_Window_Driver::driver(win)->icon_ &&
+        Fl_X11_Window_Driver::driver(win)->icon_->legacy_icon) {
       hints->icon_pixmap = (Pixmap)Fl_X11_Window_Driver::driver(win)->icon_->legacy_icon;
       hints->flags       |= IconPixmapHint;
     }
@@ -2761,7 +2762,7 @@ void Fl_X11_Window_Driver::set_icons() {
   unsigned long *net_wm_icons;
   size_t net_wm_icons_size;
 
-  if (icon_->count) {
+  if (icon_ && icon_->count) {
     icons_to_property((const Fl_RGB_Image **)icon_->icons, icon_->count,
                       &net_wm_icons, &net_wm_icons_size);
   } else {
@@ -2772,7 +2773,7 @@ void Fl_X11_Window_Driver::set_icons() {
   XChangeProperty (fl_display, fl_xid(pWindow), fl_NET_WM_ICON, XA_CARDINAL, 32,
       PropModeReplace, (unsigned char*) net_wm_icons, net_wm_icons_size);
 
-  if (icon_->count) {
+  if (icon_ && icon_->count) {
     delete [] net_wm_icons;
     net_wm_icons = 0L;
     net_wm_icons_size = 0;
diff --git a/src/drivers/Wayland/Fl_Wayland_Screen_Driver.H b/src/drivers/Wayland/Fl_Wayland_Screen_Driver.H
index f08f9cd86..aebc651ff 100644
--- a/src/drivers/Wayland/Fl_Wayland_Screen_Driver.H
+++ b/src/drivers/Wayland/Fl_Wayland_Screen_Driver.H
@@ -176,9 +176,6 @@ public:
   static compositor_name compositor; // identifies the used Wayland compositor
   void set_spot(int font, int height, int x, int y, int w, int h, Fl_Window *win);
   void reset_spot();
-#if FLTK_USE_X11
-  static bool undo_wayland_backend_if_needed(const char *backend = NULL);
-#endif
 };
 
 
diff --git a/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx b/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx
index 0f76454a8..0ea7bad37 100644
--- a/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx
+++ b/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx
@@ -140,6 +140,7 @@ struct pointer_output {
 
 Fl_Wayland_Screen_Driver::compositor_name Fl_Wayland_Screen_Driver::compositor = Fl_Wayland_Screen_Driver::unspecified;
 
+
 extern "C" {
   bool fl_libdecor_using_weston(void) {
     return Fl_Wayland_Screen_Driver::compositor == Fl_Wayland_Screen_Driver::WESTON;
@@ -1093,33 +1094,12 @@ Fl_Wayland_Screen_Driver::Fl_Wayland_Screen_Driver() : Fl_Screen_Driver() {
 }
 
 
-#if FLTK_USE_X11
-bool Fl_Wayland_Screen_Driver::undo_wayland_backend_if_needed(const char *backend) {
-  if (!backend) backend = getenv("FLTK_BACKEND");
-  if (wl_display && backend && strcmp(backend, "x11") == 0) {
-    wl_display_disconnect(wl_display);
-    wl_display = NULL;
-    if (Fl_Screen_Driver::system_driver) delete Fl_Screen_Driver::system_driver;
-    Fl_Screen_Driver::system_driver = new Fl_X11_System_Driver();
-    return true;
-  }
-  return false;
-}
-#endif
-
-
 void Fl_Wayland_Screen_Driver::open_display_platform() {
   static bool beenHereDoneThat = false;
   if (beenHereDoneThat)
     return;
 
   beenHereDoneThat = true;
-#if FLTK_USE_X11
-  if (undo_wayland_backend_if_needed()) {
-    Fl::screen_driver()->open_display();
-    return;
-  }
-#endif
 
   if (!wl_display) {
     wl_display = wl_display_connect(NULL);
@@ -1143,7 +1123,6 @@ puts("Using Wayland backend");
   }*/
   Fl::add_fd(wl_display_get_fd(wl_display), FL_READ, (Fl_FD_Handler)fd_callback, wl_display);
   fl_create_print_window();
-  Fl_Wayland_System_Driver::too_late_to_disable = true;
 }
 
 void Fl_Wayland_Screen_Driver::close_display() {
diff --git a/src/drivers/Wayland/Fl_Wayland_System_Driver.H b/src/drivers/Wayland/Fl_Wayland_System_Driver.H
index d363aa1d0..e5203581e 100644
--- a/src/drivers/Wayland/Fl_Wayland_System_Driver.H
+++ b/src/drivers/Wayland/Fl_Wayland_System_Driver.H
@@ -26,8 +26,6 @@ public:
   int event_key(int k);
   int get_key(int k);
   virtual void *control_maximize_button(void *data);
-  virtual void disable_wayland();
-  static bool too_late_to_disable;
 };
 
 #endif /* FL_WAYLAND_SYSTEM_DRIVER_H */
diff --git a/src/drivers/Wayland/Fl_Wayland_System_Driver.cxx b/src/drivers/Wayland/Fl_Wayland_System_Driver.cxx
index 219d68926..d1d5e7dad 100644
--- a/src/drivers/Wayland/Fl_Wayland_System_Driver.cxx
+++ b/src/drivers/Wayland/Fl_Wayland_System_Driver.cxx
@@ -24,9 +24,6 @@
 #include <stdlib.h>
 
 
-bool Fl_Wayland_System_Driver::too_late_to_disable = false;
-
-
 int Fl_Wayland_System_Driver::event_key(int k) {
   if (k > FL_Button && k <= FL_Button+8)
     return Fl::event_state(8<<(k-FL_Button));
@@ -92,16 +89,3 @@ void *Fl_Wayland_System_Driver::control_maximize_button(void *data) {
     return NULL;
   }
 }
-
-
-void Fl_Wayland_System_Driver::disable_wayland() {
-#if FLTK_USE_X11
-  if (too_late_to_disable) {
-    fprintf(stderr, "Error: fl_disable_wayland() cannot be called "
-            "after the Wayland display was opened\n"
-            "or a Wayland window was created or the Wayland screen was accessed\n");
-    exit(1);
-  }
-  Fl_Wayland_Screen_Driver::undo_wayland_backend_if_needed("x11");
-#endif
-}
diff --git a/src/drivers/Wayland/fl_wayland_platform_init.cxx b/src/drivers/Wayland/fl_wayland_platform_init.cxx
index e962de92b..88b863b20 100644
--- a/src/drivers/Wayland/fl_wayland_platform_init.cxx
+++ b/src/drivers/Wayland/fl_wayland_platform_init.cxx
@@ -35,15 +35,49 @@
 #include <stdio.h>
 
 
-Fl_System_Driver *Fl_System_Driver::newSystemDriver() {
+static Fl_Fontdesc built_in_table[] = {  // Pango font names
+  {"Sans"},
+  {"Sans Bold"},
+  {"Sans Italic"},
+  {"Sans Bold Italic"},
+  {"Monospace"},
+  {"Monospace Bold"},
+  {"Monospace Italic"},
+  {"Monospace Bold Italic"},
+  {"Serif"},
+  {"Serif Bold"},
+  {"Serif Italic"},
+  {"Serif Bold Italic"},
+  {"Standard Symbols PS"}, // FL_SYMBOL
+  {"Monospace"},           // FL_SCREEN
+  {"Monospace Bold"},      // FL_SCREEN_BOLD
+  {"D050000L"},            // FL_ZAPF_DINGBATS
+};
+
+
+FL_EXPORT Fl_Fontdesc *fl_fonts = built_in_table;
+
+
 #if FLTK_USE_X11
-  const char *backend = ::getenv("FLTK_BACKEND");
-  const char *xdgrt = ::getenv("XDG_RUNTIME_DIR");
-  // fprintf(stderr, "FLTK_BACKEND='%s' XDG_RUNTIME_DIR='%s'\n",
-  //         backend ? backend : "", xdgrt ? xdgrt : "");
 
+static bool attempt_wayland() {
+  if (Fl_Wayland_Screen_Driver::wl_display) return true;
+  static bool first = true;
+  static bool disable_wl = false;
+  if (first) { // get the value if it exists and cache it
+    void *sym = Fl_Posix_System_Driver::dlopen_or_dlsym(NULL, "fl_disable_wayland");
+    if (sym) {
+      disable_wl = *(bool *)sym;
+      // printf("fl_disable_wayland = %s\n", disable_wl ? "true" : "false");
+    }
+    first = false;
+  }
+  if (disable_wl)
+    return false;
+  const char *backend = ::getenv("FLTK_BACKEND");
+  // fprintf(stderr, "FLTK_BACKEND='%s'\n", backend ? backend : "");
   if (backend && strcmp(backend, "x11") == 0) {
-    return new Fl_X11_System_Driver();
+    return false;
   }
 
   if (backend && strcmp(backend, "wayland") == 0) {
@@ -52,87 +86,61 @@ Fl_System_Driver *Fl_System_Driver::newSystemDriver() {
       fprintf(stderr, "Error: no Wayland connection available, FLTK_BACKEND = '%s'\n", backend);
       exit(1);
     }
-    return new Fl_Wayland_System_Driver();
+    return true;
   }
 
   if (!backend) {
     // env var XDG_RUNTIME_DIR is required for Wayland
+    const char *xdgrt = ::getenv("XDG_RUNTIME_DIR");
     if (xdgrt) {
       // is a Wayland connection available ?
       Fl_Wayland_Screen_Driver::wl_display = wl_display_connect(NULL);
       if (Fl_Wayland_Screen_Driver::wl_display) { // Yes, use Wayland drivers
         // puts("using wayland");
-        return new Fl_Wayland_System_Driver();
+        return true;
       }
     }
     // no Wayland connection or environment variable XDG_RUNTIME_DIR not set,
     // falling back to X11
-    return new Fl_X11_System_Driver();
+    return false;
   }
 
   fprintf(stderr, "Error: unexpected value of FLTK_BACKEND: '%s'\n", backend);
   exit(1);
-  return NULL;
-#else
-  return new Fl_Wayland_System_Driver();
-#endif
+  return false;
 }
 
-
-static Fl_Fontdesc built_in_table[] = {  // Pango font names
-  {"Sans"},
-  {"Sans Bold"},
-  {"Sans Italic"},
-  {"Sans Bold Italic"},
-  {"Monospace"},
-  {"Monospace Bold"},
-  {"Monospace Italic"},
-  {"Monospace Bold Italic"},
-  {"Serif"},
-  {"Serif Bold"},
-  {"Serif Italic"},
-  {"Serif Bold Italic"},
-  {"Standard Symbols PS"}, // FL_SYMBOL
-  {"Monospace"},           // FL_SCREEN
-  {"Monospace Bold"},      // FL_SCREEN_BOLD
-  {"D050000L"},            // FL_ZAPF_DINGBATS
-};
+#endif // FLTK_USE_X11
 
 
-FL_EXPORT Fl_Fontdesc *fl_fonts = built_in_table;
+Fl_System_Driver *Fl_System_Driver::newSystemDriver() {
+#if FLTK_USE_X11
+  if (!attempt_wayland()) return new Fl_X11_System_Driver();
+#endif
+  return new Fl_Wayland_System_Driver();
+}
 
 
 Fl_Graphics_Driver *Fl_Graphics_Driver::newMainGraphicsDriver() {
 #if FLTK_USE_X11
-  Fl_Wayland_Screen_Driver::undo_wayland_backend_if_needed();
-  if (Fl_Wayland_Screen_Driver::wl_display) {
-    fl_graphics_driver = new Fl_Wayland_Graphics_Driver();
-  } else {
-    fl_graphics_driver = new Fl_Display_Cairo_Graphics_Driver();
-  }
-  return fl_graphics_driver;
-#else
-  return new Fl_Wayland_Graphics_Driver();
+  if (!attempt_wayland()) return new Fl_Display_Cairo_Graphics_Driver();
 #endif
+  return new Fl_Wayland_Graphics_Driver();
 }
 
 
 Fl_Copy_Surface_Driver *Fl_Copy_Surface_Driver::newCopySurfaceDriver(int w, int h) {
 #if FLTK_USE_X11
-  if (Fl_Wayland_Screen_Driver::wl_display) return new Fl_Wayland_Copy_Surface_Driver(w, h);
-  return new Fl_Xlib_Copy_Surface_Driver(w, h);
-#else
-  return new Fl_Wayland_Copy_Surface_Driver(w, h);
+  if (!Fl_Wayland_Screen_Driver::wl_display) return new Fl_Xlib_Copy_Surface_Driver(w, h);
 #endif
+  return new Fl_Wayland_Copy_Surface_Driver(w, h);
 }
 
 
 Fl_Screen_Driver *Fl_Screen_Driver::newScreenDriver() {
 #if FLTK_USE_X11
   if (!Fl_Screen_Driver::system_driver) Fl::system_driver();
-  Fl_Wayland_Screen_Driver::undo_wayland_backend_if_needed();
   if (Fl_Wayland_Screen_Driver::wl_display) {
-    Fl_Wayland_System_Driver::too_late_to_disable = true;
     return new Fl_Wayland_Screen_Driver();
   }
 
@@ -149,27 +157,17 @@ Fl_Screen_Driver *Fl_Screen_Driver::newScreenDriver() {
 Fl_Window_Driver *Fl_Window_Driver::newWindowDriver(Fl_Window *w)
 {
 #if FLTK_USE_X11
-  if (!Fl_Screen_Driver::system_driver) Fl::system_driver();
-  static bool been_here = false;
-  if (!been_here) {
-    been_here = true;
-    Fl_Wayland_System_Driver::too_late_to_disable = true;
-    Fl_Wayland_Screen_Driver::undo_wayland_backend_if_needed();
-  }
-  if (Fl_Wayland_Screen_Driver::wl_display) return new Fl_Wayland_Window_Driver(w);
-  return new Fl_X11_Window_Driver(w);
-#else
-  return new Fl_Wayland_Window_Driver(w);
+  if (!attempt_wayland()) return new Fl_X11_Window_Driver(w);
 #endif
+  return new Fl_Wayland_Window_Driver(w);
 }
 
 
 Fl_Image_Surface_Driver *Fl_Image_Surface_Driver::newImageSurfaceDriver(int w, int h, int high_res, Fl_Offscreen off)
 {
 #if FLTK_USE_X11
-  if (Fl_Wayland_Screen_Driver::wl_display) return new Fl_Wayland_Image_Surface_Driver(w, h, high_res, off);
-  return new Fl_Xlib_Image_Surface_Driver(w, h, high_res, off);
-#else
-  return new Fl_Wayland_Image_Surface_Driver(w, h, high_res, off);
+  if (!Fl_Wayland_Screen_Driver::wl_display)
+    return new Fl_Xlib_Image_Surface_Driver(w, h, high_res, off);
 #endif
+  return new Fl_Wayland_Image_Surface_Driver(w, h, high_res, off);
 }