all: Initial port for gtk4

Add meson changes to build a gtk4 variant of libvte, plus
a gtk4 variant of the test application.

Make the minimal code changes required to successfully build
and run on gtk4.

No event handlers yet, and no public API to replace the gtk3
specific APIs.  That will come later.

This should be good enough to get non-terminal users of libvte
started on porting to gtk4.

https://gitlab.gnome.org/GNOME/vte/-/issues/12

1 files changed, 244 insertions, 118 deletions

diff --git a/src/vte.cc b/src/vte.cc
index 64193498..d9a2ec3d 100644
--- a/src/vte.cc
+++ b/src/vte.cc
@@ -1,6 +1,6 @@
 /*
  * Copyright (C) 2001-2004,2009,2010 Red Hat, Inc.
- * Copyright © 2008, 2009, 2010 Christian Persch
+ * Copyright © 2008, 2009, 2010, 2020 Christian Persch
  *
  * This library is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published
@@ -49,6 +49,7 @@
 #include "ringview.hh"
 #include "caps.hh"
 #include "widget.hh"
+#include "cairo-glue.hh"
 
 #ifdef HAVE_WCHAR_H
 #include <wchar.h>
@@ -72,8 +73,12 @@
 #include "gobject-glue.hh"
 
 #ifdef WITH_A11Y
+#if VTE_GTK == 3
 #include "vteaccess.h"
-#endif
+#else
+#undef WITH_A11Y
+#endif /* VTE_GTK == 3 */
+#endif /* WITH_A11Y */
 
 #include <new> /* placement new */
 
@@ -95,6 +100,12 @@ static inline double round(double x) {
 
 #define VTE_DRAW_OPAQUE (1.0)
 
+#if VTE_GTK == 3
+#define VTE_STYLE_CLASS_READ_ONLY GTK_STYLE_CLASS_READ_ONLY
+#elif VTE_GTK == 4
+#define VTE_STYLE_CLASS_READ_ONLY "read-only"
+#endif
+
 namespace vte {
 namespace terminal {
 
@@ -106,7 +117,10 @@ static void remove_update_timeout(vte::terminal::Terminal* that);
 
 static gboolean process_timeout (gpointer data) noexcept;
 static gboolean update_timeout (gpointer data) noexcept;
-static cairo_region_t *vte_cairo_get_clip_region (cairo_t *cr);
+
+#if VTE_GTK == 3
+static vte::Freeable<cairo_region_t> vte_cairo_get_clip_region(cairo_t* cr);
+#endif
 
 /* these static variables are guarded by the GDK mutex */
 static guint process_timeout_tag = 0;
@@ -438,7 +452,11 @@ Terminal::invalidate_rows(vte::grid::row_t row_start,
                 rect.x += allocation.x + m_padding.left;
                 rect.y += allocation.y + m_padding.top;
                 cairo_region_t *region = cairo_region_create_rectangle(&rect);
+#if VTE_GTK == 3
 		gtk_widget_queue_draw_region(m_widget, region);
+#elif VTE_GTK == 4
+                gtk_widget_queue_draw(m_widget); // FIXMEgtk4
+#endif
                 cairo_region_destroy(region);
 	}
 
@@ -1528,6 +1546,9 @@ Terminal::regex_match_check(vte::grid::column_t column,
                             vte::grid::row_t row,
                             int* tag)
 {
+        /* Need to ensure the ringview is updated. */
+        ringview_update();
+
 	long delta = m_screen->scroll_delta;
 	_vte_debug_print(VTE_DEBUG_EVENTS | VTE_DEBUG_REGEX,
 			"Checking for match at (%ld,%ld).\n",
@@ -1568,7 +1589,11 @@ Terminal::regex_match_check(vte::grid::column_t column,
 vte::view::coords
 Terminal::view_coords_from_event(vte::platform::MouseEvent const& event) const
 {
+#if VTE_GTK == 3
         return vte::view::coords(event.x() - m_padding.left, event.y() - m_padding.top);
+#elif VTE_GTK == 4
+        return vte::view::coords(event.x(), event.y());
+#endif
 }
 
 bool
@@ -1816,10 +1841,50 @@ Terminal::rowcol_from_event(vte::platform::MouseEvent const& event,
         return true;
 }
 
-char *
+#if VTE_GTK == 4
+
+bool
+Terminal::rowcol_at(double x,
+                    double y,
+                    long* column,
+                    long* row)
+{
+        auto rowcol = grid_coords_from_view_coords(vte::view::coords(x, y));
+        if (!grid_coords_visible(rowcol))
+                return false;
+
+        *column = rowcol.column();
+        *row = rowcol.row();
+        return true;
+}
+
+char*
+Terminal::hyperlink_check_at(double x,
+                             double y)
+{
+        long col, row;
+        if (!rowcol_at(x, y, &col, &row))
+                return nullptr;
+
+        return hyperlink_check(col, row);
+}
+
+#endif /* VTE_GTK == 4 */
+
+char*
 Terminal::hyperlink_check(vte::platform::MouseEvent const& event)
 {
         long col, row;
+        if (!rowcol_from_event(event, &col, &row))
+                return nullptr;
+
+        return hyperlink_check(col, row);
+}
+
+char*
+Terminal::hyperlink_check(vte::grid::column_t col,
+                          vte::grid::row_t row)
+{
         const char *hyperlink;
         const char *separator;
 
@@ -1829,9 +1894,6 @@ Terminal::hyperlink_check(vte::platform::MouseEvent const& event)
         /* Need to ensure the ringview is updated. */
         ringview_update();
 
-        if (!rowcol_from_event(event, &col, &row))
-                return NULL;
-
         _vte_ring_get_hyperlink_at_position(m_screen->row_data, row, col, false, &hyperlink);
 
         if (hyperlink != NULL) {
@@ -1848,15 +1910,12 @@ Terminal::hyperlink_check(vte::platform::MouseEvent const& event)
         return g_strdup(hyperlink);
 }
 
-char *
+char*
 Terminal::regex_match_check(vte::platform::MouseEvent const& event,
                             int *tag)
 {
         long col, row;
 
-        /* Need to ensure the ringview is updated. */
-        ringview_update();
-
         if (!rowcol_from_event(event, &col, &row))
                 return FALSE;
 
@@ -1872,9 +1931,23 @@ Terminal::regex_match_check_extra(vte::platform::MouseEvent const& event,
                                   uint32_t match_flags,
                                   char** matches)
 {
+        long col, row;
+        if (!rowcol_from_event(event, &col, &row))
+                return false;
+
+        return regex_match_check_extra(col, row, regexes, n_regexes, match_flags, matches);
+}
+
+bool
+Terminal::regex_match_check_extra(vte::grid::column_t col,
+                                  vte::grid::row_t row,
+                                  vte::base::Regex const** regexes,
+                                  size_t n_regexes,
+                                  uint32_t match_flags,
+                                  char** matches)
+{
 	gsize offset, sattr, eattr;
         bool any_matches = false;
-        long col, row;
         guint i;
 
         assert(regexes != nullptr || n_regexes == 0);
@@ -1883,9 +1956,6 @@ Terminal::regex_match_check_extra(vte::platform::MouseEvent const& event,
         /* Need to ensure the ringview is updated. */
         ringview_update();
 
-        if (!rowcol_from_event(event, &col, &row))
-                return false;
-
 	if (m_match_contents == nullptr) {
 		match_contents_refresh();
 	}
@@ -4583,10 +4653,11 @@ Terminal::beep()
 bool
 Terminal::widget_key_press(vte::platform::KeyEvent const& event)
 {
+        auto handled = false;
 	char *normal = NULL;
 	gsize normal_length = 0;
 	struct termios tio;
-	gboolean scrolled = FALSE, steal = FALSE, modifier = FALSE, handled,
+	gboolean scrolled = FALSE, steal = FALSE, modifier = FALSE,
 		 suppress_alt_esc = FALSE, add_modifiers = FALSE;
 	guint keyval = 0;
 	gunichar keychar = 0;
@@ -4614,12 +4685,6 @@ Terminal::widget_key_press(vte::platform::KeyEvent const& event)
                         set_pointer_autohidden(true);
 		}
 
-		_vte_debug_print(VTE_DEBUG_EVENTS,
-				"Keypress, modifiers=0x%x, "
-				"keyval=0x%x\n",
-                                 m_modifiers,
-                                 keyval);
-
 		/* We steal many keypad keys here. */
 		if (!m_im_preedit_active) {
 			switch (keyval) {
@@ -4709,6 +4774,7 @@ Terminal::widget_key_press(vte::platform::KeyEvent const& event)
 
 	/* Let the input method at this one first. */
 	if (!steal && m_input_enabled) {
+                // FIXMEchpe FIXMEgtk4: update IM position? im_set_cursor_location()
                 if (m_real_widget->im_filter_keypress(event)) {
 			_vte_debug_print(VTE_DEBUG_EVENTS,
 					"Keypress taken by IM.\n");
@@ -5040,6 +5106,16 @@ Terminal::widget_key_press(vte::platform::KeyEvent const& event)
 		}
 		return true;
 	}
+
+#if VTE_GTK == 4
+        if (!handled &&
+            event.matches(GDK_KEY_Menu, 0)) {
+                _vte_debug_print(VTE_DEBUG_EVENTS, "Showing context menu\n");
+                // FIXMEgtk4 do context menu
+                handled = true;
+        }
+#endif
+
 	return false;
 }
 
@@ -5960,6 +6036,8 @@ Terminal::invalidate_match_span()
 void
 Terminal::match_hilite_update()
 {
+	_vte_debug_print(VTE_DEBUG_EVENTS, "Match hilite update\n");
+
         /* Need to ensure the ringview is updated. */
         ringview_update();
 
@@ -5973,10 +6051,6 @@ Terminal::match_hilite_update()
         vte::base::BidiRow const* bidirow = m_ringview.get_bidirow(confine_grid_row(row));
         col = bidirow->vis2log(col);
 
-	_vte_debug_print(VTE_DEBUG_EVENTS,
-                         "Match hilite update (%ld, %ld) -> %ld, %ld\n",
-                         pos.x, pos.y, col, row);
-
         /* Whether there's any chance we'd highlight something */
         bool do_check_hilite = view_coords_visible(pos) &&
                                m_mouse_cursor_over_widget &&
@@ -6768,8 +6842,7 @@ Terminal::widget_mouse_motion(vte::platform::MouseEvent const& event)
         auto rowcol = grid_coords_from_view_coords(pos);
 
 	_vte_debug_print(VTE_DEBUG_EVENTS,
-                         "Motion notify %s %s\n",
-                         pos.to_string(), rowcol.to_string());
+                         "Motion grid %s\n", rowcol.to_string());
 
         m_modifiers = event.modifiers();
 
@@ -6824,17 +6897,22 @@ Terminal::widget_mouse_press(vte::platform::MouseEvent const& event)
         /* Need to ensure the ringview is updated. */
         ringview_update();
 
+        /* Reset IM (like GtkTextView does) here */
+        if (event.press_count() == 1)
+                widget()->im_reset();
+
         auto pos = view_coords_from_event(event);
         auto rowcol = grid_coords_from_view_coords(pos);
 
+        _vte_debug_print(VTE_DEBUG_EVENTS,
+                         "Click gesture pressed button=%d at grid %s\n",
+                         event.button_value(),
+                         rowcol.to_string());
+
         m_modifiers = event.modifiers();
 
         switch (event.press_count()) {
         case 1: /* single click */
-		_vte_debug_print(VTE_DEBUG_EVENTS,
-                                 "Button %d single-click at %s\n",
-                                 event.button_value(),
-                                 rowcol.to_string());
 		/* Handle this event ourselves. */
                 switch (event.button()) {
                 case vte::platform::MouseEvent::Button::eLEFT:
@@ -6844,6 +6922,8 @@ Terminal::widget_mouse_press(vte::platform::MouseEvent const& event)
 			if (!m_has_focus)
                                 widget()->grab_focus();
 
+                        // FIXMEchpe FIXMEgtk do im_reset() here
+
 			/* If we're in event mode, and the user held down the
 			 * shift key, we start selecting. */
 			if (m_mouse_tracking_mode != MouseTrackingMode::eNONE) {
@@ -6904,10 +6984,6 @@ Terminal::widget_mouse_press(vte::platform::MouseEvent const& event)
 		}
 		break;
         case 2: /* double click */
-		_vte_debug_print(VTE_DEBUG_EVENTS,
-                                 "Button %d double-click at %s\n",
-                                 event.button_value(),
-                                 rowcol.to_string());
                 switch (event.button()) {
                 case vte::platform::MouseEvent::Button::eLEFT:
                         if (m_will_select_after_threshold) {
@@ -6928,10 +7004,6 @@ Terminal::widget_mouse_press(vte::platform::MouseEvent const& event)
 		}
 		break;
         case 3: /* triple click */
-		_vte_debug_print(VTE_DEBUG_EVENTS,
-                                 "Button %d triple-click at %s\n",
-                                 event.button_value(),
-                                 rowcol.to_string());
                 switch (event.button()) {
                 case vte::platform::MouseEvent::Button::eLEFT:
                         if ((m_mouse_handled_buttons & 1) != 0) {
@@ -6949,6 +7021,16 @@ Terminal::widget_mouse_press(vte::platform::MouseEvent const& event)
 		break;
 	}
 
+#if VTE_GTK == 4
+        if (!handled &&
+            ((event.button() == vte::platform::MouseEvent::Button::eRIGHT) ||
+             !(event.modifiers() & (GDK_BUTTON1_MASK | GDK_BUTTON2_MASK)))) {
+                _vte_debug_print(VTE_DEBUG_EVENTS, "Showing context menu\n");
+                // FIXMEgtk4 context menu
+                handled = true;
+        }
+#endif /* VTE_GTK == 4 */
+
 	/* Save the pointer state for later use. */
         if (event.button_value() >= 1 && event.button_value() <= 3)
                 m_mouse_pressed_buttons |= (1 << (event.button_value() - 1));
@@ -6973,15 +7055,16 @@ Terminal::widget_mouse_release(vte::platform::MouseEvent const& event)
         auto pos = view_coords_from_event(event);
         auto rowcol = grid_coords_from_view_coords(pos);
 
+        _vte_debug_print(VTE_DEBUG_EVENTS,
+                         "Click gesture released button=%d at grid %s\n",
+                         event.button_value(), rowcol.to_string());
+
 	stop_autoscroll();
 
         m_modifiers = event.modifiers();
 
         switch (event.type()) {
         case vte::platform::EventBase::Type::eMOUSE_RELEASE:
-		_vte_debug_print(VTE_DEBUG_EVENTS,
-                                 "Button %d released at %s\n",
-                                 event.button_value(), rowcol.to_string());
                 switch (event.button()) {
                 case vte::platform::MouseEvent::Button::eLEFT:
                         if ((m_mouse_handled_buttons & 1) != 0)
@@ -7020,8 +7103,6 @@ Terminal::widget_mouse_release(vte::platform::MouseEvent const& event)
 void
 Terminal::widget_focus_in()
 {
-	_vte_debug_print(VTE_DEBUG_EVENTS, "Focus in.\n");
-
         m_has_focus = true;
         widget()->grab_focus();
 
@@ -7049,8 +7130,6 @@ Terminal::widget_focus_in()
 void
 Terminal::widget_focus_out()
 {
-	_vte_debug_print(VTE_DEBUG_EVENTS, "Focus out.\n");
-
 	/* We only have an IM context when we're realized, and there's not much
 	 * point to painting ourselves if we don't have a window. */
 	if (widget_realized()) {
@@ -7083,8 +7162,9 @@ Terminal::widget_mouse_enter(vte::platform::MouseEvent const& event)
         auto pos = view_coords_from_event(event);
 
         // FIXMEchpe read event modifiers here
+        // FIXMEgtk4 or maybe not since there is no event to read them from on gtk4
 
-	_vte_debug_print(VTE_DEBUG_EVENTS, "Enter at %s\n", pos.to_string());
+	_vte_debug_print(VTE_DEBUG_EVENTS, "Motion enter at grid %s\n", pos.to_string());
 
         m_mouse_cursor_over_widget = TRUE;
         m_mouse_last_position = pos;
@@ -7098,14 +7178,23 @@ Terminal::widget_mouse_enter(vte::platform::MouseEvent const& event)
 void
 Terminal::widget_mouse_leave(vte::platform::MouseEvent const& event)
 {
+#if VTE_GTK == 3
         auto pos = view_coords_from_event(event);
 
         // FIXMEchpe read event modifiers here
+        // FIXMEgtk4 or maybe not since there is no event to read them from on gtk4
 
-	_vte_debug_print(VTE_DEBUG_EVENTS, "Leave at %s\n", pos.to_string());
+	_vte_debug_print(VTE_DEBUG_EVENTS, "Motion leave at grid %s\n", pos.to_string());
 
         m_mouse_cursor_over_widget = FALSE;
         m_mouse_last_position = pos;
+#elif VTE_GTK == 4
+        // FIXMEgtk4 !!!
+        m_mouse_cursor_over_widget = false;
+        // keep m_mouse_last_position since the event here has no position
+#endif
+
+        // FIXMEchpe: also set m_mouse_scroll_delta to 0 here?
 
         hyperlink_hilite_update();
         match_hilite_update();
@@ -7193,7 +7282,11 @@ Terminal::apply_font_metrics(int cell_width_unscaled,
 	/* Queue a resize if anything's changed. */
 	if (resize) {
 		if (widget_realized()) {
+#if VTE_GTK == 3
 			gtk_widget_queue_resize_no_redraw(m_widget);
+#elif VTE_GTK == 4
+                        gtk_widget_queue_resize(m_widget); // FIXMEgtk4?
+#endif
 		}
 	}
 	/* Emit a signal that the font changed. */
@@ -7306,6 +7399,7 @@ Terminal::set_font_desc(vte::Freeable<PangoFontDescription> font_desc)
 bool
 Terminal::update_font_desc()
 {
+#if VTE_GTK == 3
         auto desc = vte::Freeable<PangoFontDescription>{};
 
         auto context = gtk_widget_get_style_context(m_widget);
@@ -7315,6 +7409,16 @@ Terminal::update_font_desc()
                               &vte::get_freeable(desc),
                               nullptr);
         gtk_style_context_restore(context);
+#elif VTE_GTK == 4
+        // FIXMEgtk4
+        // This is how gtktextview does it, but the APIs are private... thanks, gtk4!
+        // desc = vte::take_freeable
+        //          (gtk_css_style_get_pango_font(gtk_style_context_lookup_style(context));
+
+        auto context = gtk_widget_get_pango_context(m_widget);
+        auto context_desc = pango_context_get_font_description(context);
+        auto desc = vte::take_freeable(pango_font_description_copy(context_desc));
+#endif /* VTE_GTK */
 
 	pango_font_description_set_family_static(desc.get(), "monospace");
 
@@ -7633,7 +7737,11 @@ Terminal::set_size(long columns,
                                                    _vte_ring_next (m_screen->row_data) - 1));
 
 		adjust_adjustments_full();
+#if VTE_GTK == 3
 		gtk_widget_queue_resize_no_redraw(m_widget);
+#elif VTE_GTK == 4
+                gtk_widget_queue_resize(m_widget); // FIXMEgtk4?
+#endif
 		/* Our visible text changed. */
 		emit_text_modified();
 	}
@@ -7798,11 +7906,9 @@ Terminal::Terminal(vte::platform::Widget* w,
 }
 
 void
-Terminal::widget_get_preferred_width(int *minimum_width,
-                                               int *natural_width)
+Terminal::widget_measure_width(int *minimum_width,
+                               int *natural_width)
 {
-	_vte_debug_print(VTE_DEBUG_LIFECYCLE, "vte_terminal_get_preferred_width()\n");
-
 	ensure_font();
 
         refresh_size();
@@ -7825,11 +7931,9 @@ Terminal::widget_get_preferred_width(int *minimum_width,
 }
 
 void
-Terminal::widget_get_preferred_height(int *minimum_height,
-                                                int *natural_height)
+Terminal::widget_measure_height(int *minimum_height,
+                                int *natural_height)
 {
-	_vte_debug_print(VTE_DEBUG_LIFECYCLE, "vte_terminal_get_preferred_height()\n");
-
 	ensure_font();
 
         refresh_size();
@@ -7852,7 +7956,17 @@ Terminal::widget_get_preferred_height(int *minimum_height,
 }
 
 void
-Terminal::widget_size_allocate(GtkAllocation *allocation)
+#if VTE_GTK == 3
+Terminal::widget_size_allocate(int allocation_x,
+                               int allocation_y,
+                               int allocation_width,
+                               int allocation_height,
+                               int allocation_baseline)
+#elif VTE_GTK == 4
+Terminal::widget_size_allocate(int allocation_width,
+                               int allocation_height,
+                               int allocation_baseline)
+#endif /* VTE_GTK */
 {
 	glong width, height;
 	gboolean repaint, update_scrollback;
@@ -7860,9 +7974,9 @@ Terminal::widget_size_allocate(GtkAllocation *allocation)
 	_vte_debug_print(VTE_DEBUG_LIFECYCLE,
 			"vte_terminal_size_allocate()\n");
 
-	width = (allocation->width - (m_padding.left + m_padding.right)) /
+	width = (allocation_width - (m_padding.left + m_padding.right)) /
 		m_cell_width;
-	height = (allocation->height - (m_padding.top + m_padding.bottom)) /
+	height = (allocation_height - (m_padding.top + m_padding.bottom)) /
 		 m_cell_height;
 	width = MAX(width, 1);
 	height = MAX(height, 1);
@@ -7870,19 +7984,21 @@ Terminal::widget_size_allocate(GtkAllocation *allocation)
 	_vte_debug_print(VTE_DEBUG_WIDGET_SIZE,
 			"[Terminal %p] Sizing window to %dx%d (%ldx%ld, padding %d,%d;%d,%d).\n",
                         m_terminal,
-			allocation->width, allocation->height,
+			allocation_width, allocation_height,
                          width, height,
                          m_padding.left, m_padding.right, m_padding.top, m_padding.bottom);
 
         auto current_allocation = get_allocated_rect();
 
-	repaint = current_allocation.width != allocation->width
-			|| current_allocation.height != allocation->height;
-	update_scrollback = current_allocation.height != allocation->height;
+	repaint = current_allocation.width != allocation_width ||
+                current_allocation.height != allocation_height;
+	update_scrollback = current_allocation.height != allocation_height;
 
-	/* Set our allocation to match the structure. */
-	gtk_widget_set_allocation(m_widget, allocation);
-        set_allocated_rect(*allocation);
+#if VTE_GTK == 3
+        set_allocated_rect({allocation_x, allocation_y, allocation_width, allocation_height});
+#elif VTE_GTK == 4
+        set_allocated_rect({0, 0, allocation_width, allocation_height});
+#endif
 
 	if (width != m_column_count
 			|| height != m_row_count
@@ -7949,8 +8065,9 @@ Terminal::set_blink_settings(bool blink,
                              int blink_time,
                              int blink_timeout) noexcept
 {
-        m_cursor_blink_cycle = blink_time / 2;
-        m_cursor_blink_timeout = blink_timeout;
+        m_cursor_blinks = m_cursor_blinks_system = blink;
+        m_cursor_blink_cycle = std::max(blink_time / 2, VTE_MIN_CURSOR_BLINK_CYCLE);
+        m_cursor_blink_timeout = std::max(blink_timeout, VTE_MIN_CURSOR_BLINK_TIMEOUT);
 
         update_cursor_blinks();
 
@@ -9222,6 +9339,7 @@ Terminal::paint_im_preedit_string()
                                         height,
                                         get_color(VTE_DEFAULT_BG), m_background_alpha);
                 }
+
 		draw_cells_with_attributes(
 							items, len,
 							m_im_preedit_attrs.get(),
@@ -9248,11 +9366,41 @@ Terminal::paint_im_preedit_string()
 	}
 }
 
+#if VTE_GTK == 3
+
+void
+Terminal::widget_draw(cairo_t* cr)
+{
+#ifdef VTE_DEBUG
+        _VTE_DEBUG_IF(VTE_DEBUG_LIFECYCLE | VTE_DEBUG_WORK | VTE_DEBUG_UPDATES) do {
+                auto clip_rect = cairo_rectangle_int_t{};
+                if (!gdk_cairo_get_clip_rectangle (cr, &clip_rect))
+                        break;
+
+                _vte_debug_print(VTE_DEBUG_LIFECYCLE, "vte_terminal_draw()\n");
+                _vte_debug_print (VTE_DEBUG_WORK, "+");
+                _vte_debug_print (VTE_DEBUG_UPDATES, "Draw (%d,%d)x(%d,%d)\n",
+                                  clip_rect.x, clip_rect.y,
+                                  clip_rect.width, clip_rect.height);
+        } while (0);
+#endif /* VTE_DEBUG */
+
+        auto region = vte_cairo_get_clip_region(cr);
+        if (!region)
+                return;
+
+        /* Transform to view coordinates */
+        cairo_region_translate(region.get(), -m_padding.left, -m_padding.top);
+
+        draw(cr, region.get());
+}
+
+#endif /* VTE_GTK == 3 */
+
 void
-Terminal::widget_draw(cairo_t *cr)
+Terminal::draw(cairo_t* cr,
+               cairo_region_t const* region)
 {
-        cairo_rectangle_int_t clip_rect;
-        cairo_region_t *region;
         int allocated_width, allocated_height;
         int extra_area_for_cursor;
         bool text_blink_enabled_now;
@@ -9261,19 +9409,6 @@ Terminal::widget_draw(cairo_t *cr)
 #endif
         gint64 now = 0;
 
-        if (!gdk_cairo_get_clip_rectangle (cr, &clip_rect))
-                return;
-
-        _vte_debug_print(VTE_DEBUG_LIFECYCLE, "vte_terminal_draw()\n");
-        _vte_debug_print (VTE_DEBUG_WORK, "+");
-        _vte_debug_print (VTE_DEBUG_UPDATES, "Draw (%d,%d)x(%d,%d)\n",
-                          clip_rect.x, clip_rect.y,
-                          clip_rect.width, clip_rect.height);
-
-        region = vte_cairo_get_clip_region (cr);
-        if (region == NULL)
-                return;
-
         allocated_width = get_allocated_width();
         allocated_height = get_allocated_height();
 
@@ -9294,9 +9429,6 @@ Terminal::widget_draw(cairo_t *cr)
 
         cairo_translate(cr, m_padding.left, m_padding.top);
 
-        /* Transform to view coordinates */
-        cairo_region_translate(region, -m_padding.left, -m_padding.top);
-
 #ifdef WITH_SIXEL
 	/* Draw images */
 	if (m_images_enabled) {
@@ -9365,8 +9497,6 @@ Terminal::widget_draw(cairo_t *cr)
 	/* Done with various structures. */
 	m_draw.set_cairo(nullptr);
 
-        cairo_region_destroy (region);
-
         /* If painting encountered any cell with blink attribute, we might need to set up a timer.
          * Blinking is implemented using a one-shot (not repeating) timer that keeps getting reinstalled
          * here as long as blinking cells are encountered during (re)painting. This way there's no need
@@ -9380,47 +9510,43 @@ Terminal::widget_draw(cairo_t *cr)
         m_invalidated_all = FALSE;
 }
 
+#if VTE_GTK == 3
+
 /* Handle an expose event by painting the exposed area. */
-static cairo_region_t *
-vte_cairo_get_clip_region (cairo_t *cr)
+static vte::Freeable<cairo_region_t>
+vte_cairo_get_clip_region(cairo_t *cr)
 {
-        cairo_rectangle_list_t *list;
-        cairo_region_t *region;
-        int i;
-
-        list = cairo_copy_clip_rectangle_list (cr);
+        auto list = vte::take_freeable(cairo_copy_clip_rectangle_list(cr));
         if (list->status == CAIRO_STATUS_CLIP_NOT_REPRESENTABLE) {
-                cairo_rectangle_int_t clip_rect;
 
-                cairo_rectangle_list_destroy (list);
+                auto clip_rect = cairo_rectangle_int_t{};
+                if (!gdk_cairo_get_clip_rectangle(cr, &clip_rect))
+                        return nullptr;
 
-                if (!gdk_cairo_get_clip_rectangle (cr, &clip_rect))
-                        return NULL;
-                return cairo_region_create_rectangle (&clip_rect);
+                return vte::take_freeable(cairo_region_create_rectangle(&clip_rect));
         }
 
+        auto region = vte::take_freeable(cairo_region_create());
+        for (auto i = list->num_rectangles - 1; i >= 0; --i) {
+                auto rect = &list->rectangles[i];
 
-        region = cairo_region_create ();
-        for (i = list->num_rectangles - 1; i >= 0; --i) {
-                cairo_rectangle_t *rect = &list->rectangles[i];
                 cairo_rectangle_int_t clip_rect;
-
                 clip_rect.x = floor (rect->x);
                 clip_rect.y = floor (rect->y);
                 clip_rect.width = ceil (rect->x + rect->width) - clip_rect.x;
                 clip_rect.height = ceil (rect->y + rect->height) - clip_rect.y;
 
-                if (cairo_region_union_rectangle (region, &clip_rect) != CAIRO_STATUS_SUCCESS) {
-                        cairo_region_destroy (region);
-                        region = NULL;
+                if (cairo_region_union_rectangle(region.get(), &clip_rect) != CAIRO_STATUS_SUCCESS) {
+                        region.reset();
                         break;
                 }
         }
 
-        cairo_rectangle_list_destroy (list);
         return region;
 }
 
+#endif /* VTE_GTK == 3 */
+
 bool
 Terminal::widget_mouse_scroll(vte::platform::ScrollEvent const& event)
 {
@@ -9652,15 +9778,11 @@ Terminal::set_rewrap_on_resize(bool rewrap)
 void
 Terminal::update_cursor_blinks()
 {
-        bool blink = false;
+        auto blink = false;
 
         switch (decscusr_cursor_blink()) {
         case CursorBlinkMode::eSYSTEM:
-                gboolean v;
-                g_object_get(gtk_widget_get_settings(m_widget),
-                                                     "gtk-cursor-blink",
-                                                     &v, nullptr);
-                blink = v != FALSE;
+                blink = m_cursor_blinks_system;
                 break;
         case CursorBlinkMode::eON:
                 blink = true;
@@ -10507,6 +10629,7 @@ Terminal::invalidate_dirty_rects_and_process_updates()
 	if (G_UNLIKELY (!m_update_rects->len))
 		return false;
 
+#if VTE_GTK == 3
         auto region = cairo_region_create();
         auto n_rects = m_update_rects->len;
         for (guint i = 0; i < n_rects; i++) {
@@ -10524,6 +10647,9 @@ Terminal::invalidate_dirty_rects_and_process_updates()
 	/* and perform the merge with the window visible area */
         gtk_widget_queue_draw_region(m_widget, region);
 	cairo_region_destroy (region);
+#elif VTE_GTK == 4
+        gtk_widget_queue_draw(m_widget); // FIXMEgtk4
+#endif
 
 	return true;
 }
@@ -10928,7 +11054,7 @@ Terminal::set_input_enabled (bool enabled)
                 if (m_has_focus)
                         widget()->im_focus_in();
 
-                gtk_style_context_remove_class (context, GTK_STYLE_CLASS_READ_ONLY);
+                gtk_style_context_remove_class (context, VTE_STYLE_CLASS_READ_ONLY);
         } else {
                 im_reset();
                 if (m_has_focus)
@@ -10937,7 +11063,7 @@ Terminal::set_input_enabled (bool enabled)
                 disconnect_pty_write();
                 _vte_byte_array_clear(m_outgoing);
 
-                gtk_style_context_add_class (context, GTK_STYLE_CLASS_READ_ONLY);
+                gtk_style_context_add_class (context, VTE_STYLE_CLASS_READ_ONLY);
         }
 
         return true;