[PATCH 7/7] ui/gtk: add clipboard support

[Gerd Hoffmann <kraxel@redhat.com>]

This patch adds clipboard support to the qemu gtk ui.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 include/ui/gtk.h   |   9 ++++
 ui/gtk-clipboard.c | 124 +++++++++++++++++++++++++++++++++++++++++++++
 ui/gtk.c           |   1 +
 ui/meson.build     |   2 +-
 4 files changed, 135 insertions(+), 1 deletion(-)
 create mode 100644 ui/gtk-clipboard.c

diff --git a/include/ui/gtk.h b/include/ui/gtk.h
index 55319843758d..08999f8835e6 100644
--- a/include/ui/gtk.h
+++ b/include/ui/gtk.h
@@ -18,6 +18,7 @@
 #include <gdk/gdkwayland.h>
 #endif
 
+#include "ui/clipboard.h"
 #include "ui/console.h"
 #include "ui/kbd-state.h"
 #if defined(CONFIG_OPENGL)
@@ -137,6 +138,11 @@ struct GtkDisplayState {
 
     bool external_pause_update;
 
+    QemuClipboardPeer cbpeer;
+    QemuClipboardInfo *cbinfo[QEMU_CLIPBOARD_SELECTION__COUNT];
+    uint32_t cbpending[QEMU_CLIPBOARD_SELECTION__COUNT];
+    GtkClipboard *gtkcb[QEMU_CLIPBOARD_SELECTION__COUNT];
+
     DisplayOptions *opts;
 };
 
@@ -208,4 +214,7 @@ QEMUGLContext gd_gl_area_get_current_context(DisplayChangeListener *dcl);
 int gd_gl_area_make_current(DisplayChangeListener *dcl,
                             QEMUGLContext ctx);
 
+/* gtk-clipboard.c */
+void gd_clipboard_init(GtkDisplayState *gd);
+
 #endif /* UI_GTK_H */
diff --git a/ui/gtk-clipboard.c b/ui/gtk-clipboard.c
new file mode 100644
index 000000000000..4a7f44b25818
--- /dev/null
+++ b/ui/gtk-clipboard.c
@@ -0,0 +1,124 @@
+/*
+ * GTK UI -- clipboard support
+ *
+ * Copyright (C) 2021 Gerd Hoffmann <kraxel@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+
+#include "ui/gtk.h"
+
+static void gd_clipboard_notify(Notifier *notifier, void *data)
+{
+    GtkDisplayState *gd = container_of(notifier, GtkDisplayState, cbpeer.update);
+    QemuClipboardInfo *info = data;
+    QemuClipboardSelection s = info->selection;
+    bool self_update = info->owner == &gd->cbpeer;
+
+    if (info != gd->cbinfo[s]) {
+        qemu_clipboard_info_put(gd->cbinfo[s]);
+        gd->cbinfo[s] = qemu_clipboard_info_get(info);
+        gd->cbpending[s] = 0;
+        if (!self_update) {
+            if (info->types[QEMU_CLIPBOARD_TYPE_TEXT].available) {
+                qemu_clipboard_request(info, QEMU_CLIPBOARD_TYPE_TEXT);
+            }
+        }
+        return;
+    }
+
+    if (self_update) {
+        return;
+    }
+
+    if (info->types[QEMU_CLIPBOARD_TYPE_TEXT].available &&
+        info->types[QEMU_CLIPBOARD_TYPE_TEXT].data) {
+        gtk_clipboard_set_text(gd->gtkcb[s],
+                               info->types[QEMU_CLIPBOARD_TYPE_TEXT].data,
+                               info->types[QEMU_CLIPBOARD_TYPE_TEXT].size);
+    }
+}
+
+static void gd_clipboard_request(QemuClipboardInfo *info,
+                                 QemuClipboardType type)
+{
+    GtkDisplayState *gd = container_of(info->owner, GtkDisplayState, cbpeer);
+    char *text;
+
+    switch (type) {
+    case QEMU_CLIPBOARD_TYPE_TEXT:
+        text = gtk_clipboard_wait_for_text(gd->gtkcb[info->selection]);
+        qemu_clipboard_set_data(&gd->cbpeer, info, type,
+                                strlen(text), text, true);
+        break;
+    default:
+        break;
+    }
+}
+
+static QemuClipboardSelection gd_find_selection(GtkDisplayState *gd,
+                                                GtkClipboard *clipboard)
+{
+    QemuClipboardSelection s;
+
+    for (s = 0; s < QEMU_CLIPBOARD_SELECTION__COUNT; s++) {
+        if (gd->gtkcb[s] == clipboard) {
+            return s;
+        }
+    }
+    return QEMU_CLIPBOARD_SELECTION_CLIPBOARD;
+}
+
+static void gd_owner_change(GtkClipboard *clipboard,
+                            GdkEvent *event,
+                            gpointer data)
+{
+    GtkDisplayState *gd = data;
+    QemuClipboardSelection s = gd_find_selection(gd, clipboard);
+    QemuClipboardInfo *info;
+
+    info = qemu_clipboard_info_new(&gd->cbpeer, s);
+    if (gtk_clipboard_wait_is_text_available(clipboard)) {
+        info->types[QEMU_CLIPBOARD_TYPE_TEXT].available = true;
+    }
+
+    qemu_clipboard_update(info);
+    qemu_clipboard_info_put(info);
+}
+
+void gd_clipboard_init(GtkDisplayState *gd)
+{
+    gd->cbpeer.name = "gtk";
+    gd->cbpeer.update.notify = gd_clipboard_notify;
+    gd->cbpeer.request = gd_clipboard_request;
+    qemu_clipboard_peer_register(&gd->cbpeer);
+
+    gd->gtkcb[QEMU_CLIPBOARD_SELECTION_CLIPBOARD] =
+        gtk_clipboard_get(gdk_atom_intern("CLIPBOARD", FALSE));
+    gd->gtkcb[QEMU_CLIPBOARD_SELECTION_PRIMARY] =
+        gtk_clipboard_get(gdk_atom_intern("PRIMARY", FALSE));
+    gd->gtkcb[QEMU_CLIPBOARD_SELECTION_SECONDARY] =
+        gtk_clipboard_get(gdk_atom_intern("SECONDARY", FALSE));
+
+    g_signal_connect(gd->gtkcb[QEMU_CLIPBOARD_SELECTION_CLIPBOARD],
+                     "owner-change", G_CALLBACK(gd_owner_change), gd);
+    g_signal_connect(gd->gtkcb[QEMU_CLIPBOARD_SELECTION_PRIMARY],
+                     "owner-change", G_CALLBACK(gd_owner_change), gd);
+    g_signal_connect(gd->gtkcb[QEMU_CLIPBOARD_SELECTION_SECONDARY],
+                     "owner-change", G_CALLBACK(gd_owner_change), gd);
+}
diff --git a/ui/gtk.c b/ui/gtk.c
index 7b412dd4fe0b..0ae3ec20f594 100644
--- a/ui/gtk.c
+++ b/ui/gtk.c
@@ -2252,6 +2252,7 @@ static void gtk_display_init(DisplayState *ds, DisplayOptions *opts)
         opts->u.gtk.grab_on_hover) {
         gtk_menu_item_activate(GTK_MENU_ITEM(s->grab_on_hover_item));
     }
+    gd_clipboard_init(s);
 }
 
 static void early_gtk_display_init(DisplayOptions *opts)
diff --git a/ui/meson.build b/ui/meson.build
index a98f89b48978..3ea969a6210b 100644
--- a/ui/meson.build
+++ b/ui/meson.build
@@ -64,7 +64,7 @@ if gtk.found()
   softmmu_ss.add(when: 'CONFIG_WIN32', if_true: files('win32-kbd-hook.c'))
 
   gtk_ss = ss.source_set()
-  gtk_ss.add(gtk, vte, pixman, files('gtk.c'))
+  gtk_ss.add(gtk, vte, pixman, files('gtk.c', 'gtk-clipboard.c'))
   gtk_ss.add(when: x11, if_true: files('x_keymap.c'))
   gtk_ss.add(when: [opengl, 'CONFIG_OPENGL'], if_true: files('gtk-egl.c', 'gtk-gl-area.c'))
   ui_modules += {'gtk' : gtk_ss}
-- 
2.29.2