Port `x-lost-selection-functions' to Haiku

* src/haiku_io.c (haiku_len): Add `CLIPBOARD_CHANGED_EVENT'.
* src/haiku_select.cc (be_update_clipboard_count): Set ownership
flags.
(be_handle_clipboard_changed_message):
(be_start_watching_selection): New functions.

* src/haiku_support.cc (class Emacs): Handle
B_CLIPBOARD_CHANGED.

* src/haiku_support.h (enum haiku_event_type): New event
`CLIPBOARD_CHANGED_EVENT'.
(struct haiku_clipboard_changed_event): New struct.

* src/haikuselect.c (haiku_handle_selection_clear)
(haiku_selection_disowned, haiku_start_watching_selections): New
functions.
(syms_of_haikuselect): New defsym and defvar.

* src/haikuselect.h: Update prototypes.
* src/haikuterm.c (haiku_read_socket): Handle selection events.
(haiku_term_init): Start watching selections.
* src/haikuterm.h: Update prototypes.
* src/keyboard.c (kbd_buffer_get_event, process_special_events)
(mark_kboards): Handle SELECTON_CLEAR_EVENTs correctly on Haiku.

1 files changed, 54 insertions, 0 deletions

diff --git a/src/haiku_select.cc b/src/haiku_select.cc
index 80c5d294820..edb821e3132 100644
--- a/src/haiku_select.cc
+++ b/src/haiku_select.cc
@@ -18,6 +18,7 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 #include <config.h>
 
+#include <Application.h>
 #include <Clipboard.h>
 #include <Message.h>
 #include <Path.h>
@@ -47,6 +48,16 @@ static int64 count_primary = -1;
 /* The number of times the secondary selection has changed.  */
 static int64 count_secondary = -1;
 
+/* Whether or not we currently think Emacs owns the primary
+   selection.  */
+static bool owned_primary;
+
+/* Likewise for the secondary selection.  */
+static bool owned_secondary;
+
+/* And the clipboard.  */
+static bool owned_clipboard;
+
 static BClipboard *
 get_clipboard_object (enum haiku_clipboard clipboard)
 {
@@ -150,14 +161,17 @@ be_update_clipboard_count (enum haiku_clipboard id)
     {
     case CLIPBOARD_CLIPBOARD:
       count_clipboard = system_clipboard->SystemCount ();
+      owned_clipboard = true;
       break;
 
     case CLIPBOARD_PRIMARY:
       count_primary = primary->SystemCount ();
+      owned_primary = true;
       break;
 
     case CLIPBOARD_SECONDARY:
       count_secondary = secondary->SystemCount ();
+      owned_secondary = true;
       break;
     }
 }
@@ -433,3 +447,43 @@ be_unlock_clipboard (enum haiku_clipboard clipboard, bool discard)
 
   board->Unlock ();
 }
+
+void
+be_handle_clipboard_changed_message (void)
+{
+  if (count_clipboard != -1
+      && (system_clipboard->SystemCount ()
+          > count_clipboard + 1)
+      && owned_clipboard)
+    {
+      owned_clipboard = false;
+      haiku_selection_disowned (CLIPBOARD_CLIPBOARD);
+    }
+
+  if (count_primary != -1
+      && (primary->SystemCount ()
+          > count_primary + 1)
+      && owned_primary)
+    {
+      owned_primary = false;
+      haiku_selection_disowned (CLIPBOARD_PRIMARY);
+    }
+
+  if (count_secondary != -1
+      && (secondary->SystemCount ()
+          > count_secondary + 1)
+      && owned_secondary)
+    {
+      owned_secondary = false;
+      haiku_selection_disowned (CLIPBOARD_SECONDARY);
+    }
+}
+
+void
+be_start_watching_selection (enum haiku_clipboard id)
+{
+  BClipboard *clipboard;
+
+  clipboard = get_clipboard_object (id);
+  clipboard->StartWatching (be_app);
+}