From: Po Lu <luangruo@yahoo.com>
Date: Sat, 11 Jun 2022 06:11:28 +0000 (+0800)
Subject: Fix queuing already-present selection requests
X-Git-Tag: emacs-29.0.90~1910^2~83
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=46b9bfb9fc925b8cf20b0a35469f8ff6c3be5a70;p=emacs.git

Fix queuing already-present selection requests

* src/xterm.c (x_defer_selection_requests): Move kbd_fetch_ptr
if possible and fix counter increment order.
---

diff --git a/src/xterm.c b/src/xterm.c
index 74716dfe408..55cd5286fe1 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -795,9 +795,9 @@ static int x_use_pending_selection_requests;
 
 static void x_push_selection_request (struct selection_input_event *);
 
-/* Defer selection requests.  Any selection requests generated after
-   this can then be processed by calling
-   `x_handle_pending_selection_requests'.
+/* Defer selection requests.  Between this and
+   x_release_selection_requests, any selection requests can be
+   processed by calling `x_handle_pending_selection_requests'.
 
    Also run through and queue all the selection events already in the
    keyboard buffer.  */
@@ -805,10 +805,11 @@ void
 x_defer_selection_requests (void)
 {
   union buffered_input_event *event;
+  bool between;
 
-  block_input ();
-  x_use_pending_selection_requests++;
+  between = false;
 
+  block_input ();
   if (!x_use_pending_selection_requests)
     {
       event = kbd_fetch_ptr;
@@ -822,13 +823,24 @@ x_defer_selection_requests (void)
 
 	      /* Mark this selection event as invalid.   */
 	      SELECTION_EVENT_DPYINFO (&event->sie) = NULL;
+
+	      /* Move the kbd_fetch_ptr along if doing so would not
+		 result in any other events being skipped.  This
+		 avoids exhausting the keyboard buffer with some
+		 over-enthusiastic clipboard managers.  */
+	      if (!between)
+		kbd_fetch_ptr = (event == kbd_buffer + KBD_BUFFER_SIZE - 1
+				 ? kbd_buffer : event + 1);
 	    }
+	  else
+	    between = true;
 
 	  event = (event == kbd_buffer + KBD_BUFFER_SIZE - 1
 		   ? kbd_buffer : event + 1);
 	}
     }
 
+  x_use_pending_selection_requests++;
   unblock_input ();
 }