gtk: window sizing overhaul

Major overhaul for window size handling.  This basically switches qemu
over to use geometry hints for the window manager instead of trying to
get the job done with widget resize requests.  This allows to specify
better what we need and also avoids window resizes.

FIXME: on gtk2 someone overwrites the geometry hints :(
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

ui/gtk.c

@@ -74,6 +74,12 @@
 #endif
 
 #define MAX_VCS 10
+#define VC_WINDOW_X_MIN  320
+#define VC_WINDOW_Y_MIN  240
+#define VC_TERM_X_MIN     80
+#define VC_TERM_Y_MIN     25
+#define VC_SCALE_MIN    0.25
+#define VC_SCALE_STEP   0.25
 
 #if !defined(CONFIG_VTE)
 # define VTE_CHECK_VERSION(a, b, c) 0
@@ -322,29 +328,63 @@ static void gd_update_caption(GtkDisplayState *s)
     g_free(prefix);
 }
 
-static void gd_update_windowsize(VirtualConsole *vc)
+static void gd_update_geometry_hints(VirtualConsole *vc)
 {
     GtkDisplayState *s = vc->s;
-    double sx, sy;
+    GdkWindowHints mask = 0;
+    GdkGeometry geo = {};
+    GtkWidget *geo_widget = NULL;
+    GtkWindow *geo_window;
 
-    if (vc->type != GD_VC_GFX || s->full_screen) {
-        return;
+    if (vc->type == GD_VC_GFX) {
+        if (s->free_scale) {
+            geo.min_width  = surface_width(vc->gfx.ds) * VC_SCALE_MIN;
+            geo.min_height = surface_height(vc->gfx.ds) * VC_SCALE_MIN;
+            mask |= GDK_HINT_MIN_SIZE;
+        } else {
+            geo.min_width  = surface_width(vc->gfx.ds) * vc->gfx.scale_x;
+            geo.min_height = surface_height(vc->gfx.ds) * vc->gfx.scale_y;
+            mask |= GDK_HINT_MIN_SIZE;
+        }
+        geo_widget = vc->gfx.drawing_area;
+        gtk_widget_set_size_request(geo_widget, geo.min_width, geo.min_height);
+
+#if defined(CONFIG_VTE)
+    } else if (vc->type == GD_VC_VTE) {
+        VteTerminal *term = VTE_TERMINAL(vc->vte.terminal);
+        GtkBorder *ib;
+
+        geo.width_inc  = vte_terminal_get_char_width(term);
+        geo.height_inc = vte_terminal_get_char_height(term);
+        mask |= GDK_HINT_RESIZE_INC;
+        geo.base_width  = geo.width_inc;
+        geo.base_height = geo.height_inc;
+        mask |= GDK_HINT_BASE_SIZE;
+        geo.min_width  = geo.width_inc * VC_TERM_X_MIN;
+        geo.min_height = geo.height_inc * VC_TERM_Y_MIN;
+        mask |= GDK_HINT_MIN_SIZE;
+        gtk_widget_style_get(vc->vte.terminal, "inner-border", &ib, NULL);
+        geo.base_width  += ib->left + ib->right;
+        geo.base_height += ib->top + ib->bottom;
+        geo.min_width   += ib->left + ib->right;
+        geo.min_height  += ib->top + ib->bottom;
+        geo_widget = vc->vte.terminal;
+#endif
     }
 
-    if (s->free_scale) {
-        sx = 1.0;
-        sy = 1.0;
-    } else {
-        sx = vc->gfx.scale_x;
-        sy = vc->gfx.scale_y;
-    }
-    gtk_widget_set_size_request(vc->gfx.drawing_area,
-                                surface_width(vc->gfx.ds) * sx,
-                                surface_height(vc->gfx.ds) * sy);
-    if (vc->window) {
-        gtk_window_resize(GTK_WINDOW(vc->window), 320, 240);
-    } else {
-        gtk_window_resize(GTK_WINDOW(s->window), 320, 240);
+    geo_window = GTK_WINDOW(vc->window ? vc->window : s->window);
+    gtk_window_set_geometry_hints(geo_window, geo_widget, &geo, mask);
+}
+
+static void gd_update_windowsize(VirtualConsole *vc)
+{
+    GtkDisplayState *s = vc->s;
+
+    gd_update_geometry_hints(vc);
+
+    if (vc->type == GD_VC_GFX && !s->full_screen && !s->free_scale) {
+        gtk_window_resize(GTK_WINDOW(vc->window ? vc->window : s->window),
+                          VC_WINDOW_X_MIN, VC_WINDOW_Y_MIN);
     }
 }
 
@@ -991,7 +1031,7 @@ static void gd_menu_untabify(GtkMenuItem *item, void *opaque)
         GClosure *cb = g_cclosure_new_swap(G_CALLBACK(gd_win_grab), vc, NULL);
         gtk_accel_group_connect(ag, GDK_KEY_g, HOTKEY_MODIFIERS, 0, cb);
 
-        fprintf(stderr, "%s: %p\n", __func__, vc);
+        gd_update_geometry_hints(vc);
         gd_update_caption(s);
     }
 }
@@ -1019,9 +1059,7 @@ static void gd_menu_full_screen(GtkMenuItem *item, void *opaque)
         if (vc->type == GD_VC_GFX) {
             vc->gfx.scale_x = 1.0;
             vc->gfx.scale_y = 1.0;
-            gtk_widget_set_size_request(vc->gfx.drawing_area,
-                                        surface_width(vc->gfx.ds),
-                                        surface_height(vc->gfx.ds));
+            gd_update_windowsize(vc);
             gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item),
                                            FALSE);
         }
@@ -1038,8 +1076,8 @@ static void gd_menu_zoom_in(GtkMenuItem *item, void *opaque)
     gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->zoom_fit_item),
                                    FALSE);
 
-    vc->gfx.scale_x += .25;
-    vc->gfx.scale_y += .25;
+    vc->gfx.scale_x += VC_SCALE_STEP;
+    vc->gfx.scale_y += VC_SCALE_STEP;
 
     gd_update_windowsize(vc);
 }
@@ -1052,11 +1090,11 @@ static void gd_menu_zoom_out(GtkMenuItem *item, void *opaque)
     gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->zoom_fit_item),
                                    FALSE);
 
-    vc->gfx.scale_x -= .25;
-    vc->gfx.scale_y -= .25;
+    vc->gfx.scale_x -= VC_SCALE_STEP;
+    vc->gfx.scale_y -= VC_SCALE_STEP;
 
-    vc->gfx.scale_x = MAX(vc->gfx.scale_x, .25);
-    vc->gfx.scale_y = MAX(vc->gfx.scale_y, .25);
+    vc->gfx.scale_x = MAX(vc->gfx.scale_x, VC_SCALE_MIN);
+    vc->gfx.scale_y = MAX(vc->gfx.scale_y, VC_SCALE_MIN);
 
     gd_update_windowsize(vc);
 }
@@ -1083,9 +1121,9 @@ static void gd_menu_zoom_fit(GtkMenuItem *item, void *opaque)
         s->free_scale = FALSE;
         vc->gfx.scale_x = 1.0;
         vc->gfx.scale_y = 1.0;
-        gd_update_windowsize(vc);
     }
 
+    gd_update_windowsize(vc);
     gd_update_full_redraw(vc);
 }
 
@@ -1279,6 +1317,7 @@ static void gd_change_page(GtkNotebook *nb, gpointer arg1, guint arg2,
     }
     gtk_widget_set_sensitive(s->grab_item, on_vga);
 
+    gd_update_windowsize(vc);
     gd_update_cursor(vc);
 }
 
@@ -1408,7 +1447,8 @@ static GSList *gd_vc_vte_init(GtkDisplayState *s, VirtualConsole *vc,
     g_signal_connect(vc->vte.terminal, "commit", G_CALLBACK(gd_vc_in), vc);
 
     vte_terminal_set_scrollback_lines(VTE_TERMINAL(vc->vte.terminal), -1);
-    vte_terminal_set_size(VTE_TERMINAL(vc->vte.terminal), 80, 25);
+    vte_terminal_set_size(VTE_TERMINAL(vc->vte.terminal),
+                          VC_TERM_X_MIN, VC_TERM_Y_MIN);
 
 #if VTE_CHECK_VERSION(0, 28, 0) && GTK_CHECK_VERSION(3, 0, 0)
     vadjustment = gtk_scrollable_get_vadjustment