clipboard: avoid error flood during :redir

redir_write():
- This is a "batch" operation which was not yet covered by
  start_batch_changes()

adjust_clipboard_name():
- msg() and friends during :redir will, of course, cause redir_write()
  to try to capture that message, which causes recursion.
- EMSG() here is trouble: if it interrupts :redir it is a mess.
  Rather than deal with the mess, show a non-error message.

closes #7182
closes #7184
closes #7183
ref #6048
ref #7032

1 files changed, 2 insertions, 0 deletions

diff --git a/src/nvim/message.c b/src/nvim/message.c
index b90c475ede..fe4cb65779 100644
--- a/src/nvim/message.c
+++ b/src/nvim/message.c
@@ -2519,6 +2519,7 @@ static void redir_write(const char *const str, const ptrdiff_t maxlen)
   if (redirecting()) {
     /* If the string doesn't start with CR or NL, go to msg_col */
     if (*s != '\n' && *s != '\r') {
+      start_batch_changes();
       while (cur_col < msg_col) {
         if (capture_ga) {
           ga_concat_len(capture_ga, " ", 1);
@@ -2535,6 +2536,7 @@ static void redir_write(const char *const str, const ptrdiff_t maxlen)
         }
         cur_col++;
       }
+      end_batch_changes();
     }
 
     size_t len = maxlen == -1 ? STRLEN(s) : (size_t)maxlen;