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, 30 insertions, 9 deletions

diff --git a/src/clipboard-gtk.cc b/src/clipboard-gtk.cc
index a70c0eea..402e3a41 100644
--- a/src/clipboard-gtk.cc
+++ b/src/clipboard-gtk.cc
@@ -22,6 +22,7 @@
 #include "widget.hh"
 #include "vteinternal.hh"
 
+#include <new>
 #include <stdexcept>
 #include <utility>
 
@@ -42,12 +43,20 @@ Clipboard::Clipboard(Widget& delegate,
 
         switch (type) {
         case ClipboardType::PRIMARY:
-                m_clipboard = vte::glib::make_ref(gtk_clipboard_get_for_display(display,
-                                                                                GDK_SELECTION_PRIMARY));
+                m_clipboard = vte::glib::make_ref
+#if VTE_GTK == 3
+                        (gtk_clipboard_get_for_display(display, GDK_SELECTION_PRIMARY));
+#elif VTE_GTK == 4
+                        (gdk_display_get_primary_clipboard(display));
+#endif
                 break;
         case ClipboardType::CLIPBOARD:
-                m_clipboard = vte::glib::make_ref(gtk_clipboard_get_for_display(display,
-                                                                                GDK_SELECTION_CLIPBOARD));
+                m_clipboard = vte::glib::make_ref
+#if VTE_GTK == 3
+                        (gtk_clipboard_get_for_display(display, GDK_SELECTION_CLIPBOARD));
+#elif VTE_GTK == 4
+                        (gdk_display_get_clipboard(display));
+#endif
                 break;
         }
 
@@ -55,6 +64,8 @@ Clipboard::Clipboard(Widget& delegate,
                 throw std::runtime_error{"Failed to create clipboard"};
 }
 
+#if VTE_GTK == 3
+
 class Clipboard::Offer {
 public:
         Offer(Clipboard& clipboard,
@@ -75,7 +86,7 @@ public:
         {
                 auto [targets, n_targets] = targets_for_format(format);
 
-                // Transfers clipboardship of *offer to the clipboard. If setting succeeds,
+                // Transfers ownership of *offer to the clipboard. If setting succeeds,
                 // the clipboard will own *offer until the clipboard_data_clear_cb
                 // callback is called.
                 // If setting the clipboard fails, the clear callback will never be
@@ -150,8 +161,8 @@ private:
                          guint info,
                          void* user_data) noexcept
         {
-                if (info != vte::to_integral(ClipboardFormat::TEXT) &&
-                    info != vte::to_integral(ClipboardFormat::HTML))
+                if (int(info) != vte::to_integral(ClipboardFormat::TEXT) &&
+                    int(info) != vte::to_integral(ClipboardFormat::HTML))
                         return;
 
                 reinterpret_cast<Offer*>(user_data)->dispatch_get(ClipboardFormat(info), data);
@@ -161,12 +172,11 @@ private:
         clipboard_clear_cb(GtkClipboard* clipboard,
                            void* user_data) noexcept
         {
-                // Assume ownership of the Request, and delete it after dispatching the callback
+                // Assume ownership of the Offer, and delete it after dispatching the callback
                 auto offer = std::unique_ptr<Offer>{reinterpret_cast<Offer*>(user_data)};
                 offer->dispatch_clear();
         }
 
-
         static std::pair<GtkTargetEntry*, int>
         targets_for_format(ClipboardFormat format)
         {
@@ -227,6 +237,8 @@ private:
 
 }; // class Clipboard::Offer
 
+#endif /* VTE_GTK == 3 */
+
 class Clipboard::Request {
 public:
         Request(Clipboard& clipboard,
@@ -244,10 +256,12 @@ public:
 
         static void run(std::unique_ptr<Request> request) noexcept
         {
+#if VTE_GTK == 3
                 auto platform = request->clipboard().platform();
                 gtk_clipboard_request_text(platform,
                                            text_received_cb,
                                            request.release());
+#endif /* VTE_GTK */
         }
 
 private:
@@ -255,6 +269,7 @@ private:
         RequestDoneCallback m_done_callback;
         RequestFailedCallback m_failed_callback;
 
+#if VTE_GTK == 3
         void dispatch(char const *text) noexcept
         try
         {
@@ -278,6 +293,8 @@ private:
                 request->dispatch(text);
         }
 
+#endif /* VTE_GTK */
+
 }; // class Clipboard::Request
 
 void
@@ -285,13 +302,17 @@ Clipboard::offer_data(ClipboardFormat format,
                       OfferGetCallback get_callback,
                       OfferClearCallback clear_callback) /* throws */
 {
+#if VTE_GTK == 3
         Offer::run(std::make_unique<Offer>(*this, get_callback, clear_callback), format);
+#endif
 }
 
 void
 Clipboard::set_text(std::string_view const& text) noexcept
 {
+#if VTE_GTK == 3
         gtk_clipboard_set_text(platform(), text.data(), text.size());
+#endif
 }
 
 void