Implement TIMESTAMP target for Haiku selections

* lisp/term/haiku-win.el (haiku-selection-targets): Fix return
values.
(gui-backend-get-selection): Handle TIMESTAMP specially.
* src/haiku_select.cc (be_get_clipboard_count): New function.
* src/haikuselect.c (Fhaiku_selection_timestamp): New function.
(syms_of_haikuselect): Add new defsubr.
* src/haikuselect.h: Update prototypes.

3 files changed, 28 insertions, 0 deletions

diff --git a/src/haiku_select.cc b/src/haiku_select.cc
index e1f2a815241..872da1d6c44 100644
--- a/src/haiku_select.cc
+++ b/src/haiku_select.cc
@@ -508,3 +508,12 @@ be_selection_outdated_p (enum haiku_clipboard id, int64 count)
 
   return false;
 }
+
+int64
+be_get_clipboard_count (enum haiku_clipboard id)
+{
+  BClipboard *clipboard;
+
+  clipboard = get_clipboard_object (id);
+  return clipboard->SystemCount ();
+}
diff --git a/src/haikuselect.c b/src/haikuselect.c
index 9d8c4a2cd16..dc0a7edf430 100644
--- a/src/haikuselect.c
+++ b/src/haikuselect.c
@@ -54,6 +54,23 @@ haiku_get_clipboard_name (Lisp_Object clipboard)
   signal_error ("Invalid clipboard", clipboard);
 }
 
+DEFUN ("haiku-selection-timestamp", Fhaiku_selection_timestamp,
+       Shaiku_selection_timestamp, 1, 1, 0,
+       doc: /* Retrieve the "timestamp" of the clipboard CLIPBOARD.
+CLIPBOARD can either be the symbol `PRIMARY', `SECONDARY' or
+`CLIPBOARD'.  The timestamp is returned as a number describing the
+number of times programs have put data into CLIPBOARD.  */)
+  (Lisp_Object clipboard)
+{
+  enum haiku_clipboard clipboard_name;
+  int64 timestamp;
+
+  clipboard_name = haiku_get_clipboard_name (clipboard);
+  timestamp = be_get_clipboard_count (clipboard_name);
+
+  return INT_TO_INTEGER (timestamp);
+}
+
 DEFUN ("haiku-selection-data", Fhaiku_selection_data, Shaiku_selection_data,
        2, 2, 0,
        doc: /* Retrieve content typed as NAME from the clipboard
@@ -1122,6 +1139,7 @@ These are only called if a connection to the Haiku display was opened.  */);
   DEFSYM (Qalready_running, "already-running");
 
   defsubr (&Shaiku_selection_data);
+  defsubr (&Shaiku_selection_timestamp);
   defsubr (&Shaiku_selection_put);
   defsubr (&Shaiku_selection_owner_p);
   defsubr (&Shaiku_drag_message);
diff --git a/src/haikuselect.h b/src/haikuselect.h
index 61efeb9cd93..42e9c93f7e9 100644
--- a/src/haikuselect.h
+++ b/src/haikuselect.h
@@ -67,6 +67,7 @@ extern void be_unlock_clipboard (enum haiku_clipboard, bool);
 extern void be_handle_clipboard_changed_message (void);
 extern void be_start_watching_selection (enum haiku_clipboard);
 extern bool be_selection_outdated_p (enum haiku_clipboard, int64);
+extern int64 be_get_clipboard_count (enum haiku_clipboard);
 
 #ifdef __cplusplus
 };