xwayland: Add a new command line option to enable selection bridge

Add a new commmand line option to enable the Xwayland
clipboard selection bridge when running in rootful mode.

By default, clipboard selection bridge is disabled to keep the default
of having Xwayland rootful running isolated from the rest of the
applications.

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>

hw/xwayland/man/Xwayland.man

@@ -65,6 +65,13 @@ option with Xwayland.
 This option has no effect if the compositor doesn't support the relevant
 XDG portal or if Xwayland was not compiled with EI and OEFFIS support.
 .TP 8
+.B \-enable-clipboard
+Enable the Xwayland clipboard selection bridge in rootful mode, syncing
+the X11 CLIPBOARD and PRIMARY selections with the Wayland clipboard and
+primary selection.
+
+This option is not compatible with rootless mode (\fI-rootless\fP).
+.TP 8
 .B \-fullscreen
 Set the Xwayland window fullscreen when running rootful.
 

hw/xwayland/xwayland-screen.c

@@ -992,6 +992,9 @@ xwl_screen_init(ScreenPtr pScreen, int argc, char **argv)
             ErrorF("This build does not have XDG portal support\n");
 #endif
         }
+        else if (strcmp(argv[i], "-enable-clipboard") == 0) {
+            xwl_screen->enable_clipboard = 1;
+        }
         else if (strcmp(argv[i], "-nokeymap") == 0) {
             xwl_screen->nokeymap = 1;
         }
@@ -1077,6 +1080,11 @@ xwl_screen_init(ScreenPtr pScreen, int argc, char **argv)
         return FALSE;
     }
 
+    if (xwl_screen->rootless && xwl_screen->enable_clipboard) {
+        ErrorF("error, cannot use the clipboard selection bridge when running rootless\n");
+        return FALSE;
+    }
+
     if (!xwl_screen->rootless && !xwl_screen->xdg_wm_base) {
         ErrorF("missing XDG-WM-Base protocol\n");
         return FALSE;

hw/xwayland/xwayland-screen.h

@@ -66,6 +66,7 @@ struct xwl_screen {
     int has_grab;
     int decorate;
     int enable_ei_portal;
+    int enable_clipboard;
     int nokeymap;
     int hidpi;
 

hw/xwayland/xwayland-selection.c

@@ -1111,6 +1111,9 @@ xwl_selection_init(struct xwl_seat *xwl_seat)
     if (xwl_screen->rootless)
         return;
 
+    if (!xwl_screen->enable_clipboard)
+        return;
+
     if (xwl_screen->selection_bridge)
         return;
 

hw/xwayland/xwayland.c

@@ -119,6 +119,7 @@ ddxUseMsg(void)
 #ifdef XWL_HAS_EI_PORTAL
     ErrorF("-enable-ei-portal      use the XDG portal for input emulation\n");
 #endif
+    ErrorF("-enable-clipboard      enable Xwayland clipboard selection bridge\n");
 }
 
 static int init_fd = -1;
@@ -247,6 +248,9 @@ ddxProcessArgument(int argc, char *argv[], int i)
     else if (strcmp(argv[i], "-enable-ei-portal") == 0) {
         return 1;
     }
+    else if (strcmp(argv[i], "-enable-clipboard") == 0) {
+        return 1;
+    }
     else if (strcmp(argv[i], "-output") == 0) {
         CHECK_FOR_REQUIRED_ARGUMENTS(1);
         return 2;