clipboard: Use gtk_clipboard_request_text for text data

Currently, when the agent asks us for VD_AGENT_CLIPBOARD_UTF8_TEXT data,
spice-gtk looks up for the first X11 target which would provide it with
UTF8_TEXT data, and uses that for the clipboard request. This means we
will use UTF8_STRING as the target for gtk_clipboard_request_contents().

However, some applications who can copy and paste text do not
necessarily support the UTF8_STRING target. This is the case for Motif
applications which support the STRING target however. It turns out gtk+
also provides a gtk_clipboard_request_text() method which will try
several targets (UTF8_TEXT, COMPOUND_TEXT, TEXT), and will ensure the
returned string is UTF-8, so we can use that when the agent asks us for
some text data.

This fixes https://bugzilla.redhat.com/show_bug.cgi?id=1348624

1 files changed, 52 insertions, 15 deletions

diff --git a/src/spice-gtk-session.c b/src/spice-gtk-session.c
index fb7630d..7b75117 100644
--- a/src/spice-gtk-session.c
+++ b/src/spice-gtk-session.c
@@ -953,6 +953,40 @@ static char *fixup_clipboard_text(SpiceGtkSession *self, const char *text, int *
     return conv;
 }
 
+static void clipboard_received_text_cb(GtkClipboard *clipboard,
+                                       const gchar *text,
+                                       gpointer user_data)
+{
+    WeakRef *weakref = user_data;
+    SpiceGtkSession *self = (SpiceGtkSession*)weakref->object;
+    char *conv = NULL;
+    int len = 0;
+    int selection;
+
+    weak_unref(weakref);
+
+    if (self == NULL)
+        return;
+
+    g_return_if_fail(SPICE_IS_GTK_SESSION(self));
+
+    selection = get_selection_from_clipboard(self->priv, clipboard);
+    g_return_if_fail(selection != -1);
+
+    len = strlen(text);
+    if (!check_clipboard_size_limits(self, len)) {
+        return;
+    }
+
+    /* gtk+ internal utf8 newline is always LF, even on windows */
+    conv = fixup_clipboard_text(self, text, &len);
+
+    spice_main_clipboard_selection_notify(self->priv->main, selection,
+                                          VD_AGENT_CLIPBOARD_UTF8_TEXT,
+                                          (guchar *)(conv ?: text), len);
+    g_free(conv);
+}
+
 static void clipboard_received_cb(GtkClipboard *clipboard,
                                   GtkSelectionData *selection_data,
                                   gpointer user_data)
@@ -998,16 +1032,14 @@ static void clipboard_received_cb(GtkClipboard *clipboard,
     }
 
     const guchar *data = gtk_selection_data_get_data(selection_data);
-    gpointer conv = NULL;
 
-    /* gtk+ internal utf8 newline is always LF, even on windows */
-    if (type == VD_AGENT_CLIPBOARD_UTF8_TEXT) {
-        conv = fixup_clipboard_text(self, (gchar *)data, &len);
-    }
+    /* text should be handled through clipboard_received_text_cb(), not
+     * clipboard_received_cb().
+     */
+    g_warn_if_fail(type != VD_AGENT_CLIPBOARD_UTF8_TEXT);
 
     spice_main_clipboard_selection_notify(s->main, selection, type,
-                                          conv ?: data, len);
-    g_free(conv);
+                                          data, len);
 }
 
 static gboolean clipboard_request(SpiceMainChannel *main, guint selection,
@@ -1030,16 +1062,21 @@ static gboolean clipboard_request(SpiceMainChannel *main, guint selection,
     cb = get_clipboard_from_selection(s, selection);
     g_return_val_if_fail(cb != NULL, FALSE);
 
-    for (m = 0; m < SPICE_N_ELEMENTS(atom2agent); m++) {
-        if (atom2agent[m].vdagent == type)
-            break;
-    }
+    if (type == VD_AGENT_CLIPBOARD_UTF8_TEXT) {
+        gtk_clipboard_request_text(cb, clipboard_received_text_cb,
+                                   weak_ref(G_OBJECT(self)));
+    } else {
+        for (m = 0; m < SPICE_N_ELEMENTS(atom2agent); m++) {
+            if (atom2agent[m].vdagent == type)
+                break;
+        }
 
-    g_return_val_if_fail(m < SPICE_N_ELEMENTS(atom2agent), FALSE);
+        g_return_val_if_fail(m < SPICE_N_ELEMENTS(atom2agent), FALSE);
 
-    atom = gdk_atom_intern_static_string(atom2agent[m].xatom);
-    gtk_clipboard_request_contents(cb, atom, clipboard_received_cb,
-                                   weak_ref(G_OBJECT(self)));
+        atom = gdk_atom_intern_static_string(atom2agent[m].xatom);
+        gtk_clipboard_request_contents(cb, atom, clipboard_received_cb,
+                                       weak_ref(G_OBJECT(self)));
+    }
 
     return TRUE;
 }