From aa1353947e975094de6ff46fea0dca5bbb2dcbb7 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Fri, 12 Jul 2024 11:21:18 +0000
Subject: [PATCH] UTF-8 keys now contain the internal representation and not
 the Unicode codepoint, so convert extended keys properly. From Stanislav
 Kljuhhin.

---
 tmux.h     |  1 +
 tty-keys.c | 11 +++++++++++
 utf8.c     | 22 ++++++++++++++++++++++
 3 files changed, 34 insertions(+)

diff --git a/tmux.h b/tmux.h
index 7bfe0e8d..b0071b25 100644
--- a/tmux.h
+++ b/tmux.h
@@ -3267,6 +3267,7 @@ void		 session_renumber_windows(struct session *);
 
 /* utf8.c */
 enum utf8_state	 utf8_towc (const struct utf8_data *, wchar_t *);
+enum utf8_state	 utf8_fromwc(wchar_t wc, struct utf8_data *);
 int		 utf8_in_table(wchar_t, const wchar_t *, u_int);
 utf8_char	 utf8_build_one(u_char);
 enum utf8_state	 utf8_from_data(const struct utf8_data *, utf8_char *);
diff --git a/tty-keys.c b/tty-keys.c
index d838e4e9..17fe47ad 100644
--- a/tty-keys.c
+++ b/tty-keys.c
@@ -911,6 +911,8 @@ tty_keys_extended_key(struct tty *tty, const char *buf, size_t len,
 	cc_t		 bspace;
 	key_code	 nkey;
 	key_code	 onlykey;
+	struct utf8_data ud;
+	utf8_char        uc;
 
 	*size = 0;
 
@@ -960,6 +962,15 @@ tty_keys_extended_key(struct tty *tty, const char *buf, size_t len,
 	else
 		nkey = number;
 
+	/* Convert UTF-32 codepoint into internal representation. */
+	if (nkey & ~0x7f) {
+		if (utf8_fromwc(nkey, &ud) == UTF8_DONE &&
+		    utf8_from_data(&ud, &uc) == UTF8_DONE)
+			nkey = uc;
+		else
+			return (-1);
+	}
+
 	/* Update the modifiers. */
 	if (modifiers > 0) {
 		modifiers--;
diff --git a/utf8.c b/utf8.c
index 03ab7e93..5c805cbd 100644
--- a/utf8.c
+++ b/utf8.c
@@ -441,6 +441,28 @@ utf8_towc(const struct utf8_data *ud, wchar_t *wc)
 	return (UTF8_DONE);
 }
 
+/* Convert wide character to UTF-8 character. */
+enum utf8_state
+utf8_fromwc(wchar_t wc, struct utf8_data *ud)
+{
+	int	size, width;
+
+	size = wctomb(ud->data, wc);
+	if (size < 0) {
+		log_debug("UTF-8 %d, wctomb() %d", wc, errno);
+		wctomb(NULL, 0);
+		return (UTF8_ERROR);
+	}
+	if (size == 0)
+		return (UTF8_ERROR);
+	ud->size = ud->have = size;
+	if (utf8_width(ud, &width) == UTF8_DONE) {
+		ud->width = width;
+		return (UTF8_DONE);
+	}
+	return (UTF8_ERROR);
+}
+
 /*
  * Open UTF-8 sequence.
  *