[hackers] [st][PATCH] Fix overtyping wide characters.

From: jamin <acdimalev_AT_gmail.com>
Date: Wed, 29 Dec 2021 09:07:17 -0800

Overtyping the first half of a wide character with the
second half of a wide character results in display garbage.
This is because the trailing dummy is not cleaned up.

i.e. ATTR_WIDE, ATTR_WDUMMY, ATTR_WDUMMY

Here is a short script for demonstrating the behavior:

        #!/bin/sh
        alias printf=/usr/bin/printf
        printf こんにちは！; sleep 2
        printf '\x1b[5D'; sleep 2
        printf へ; sleep 2
        printf ' '; sleep 2
        echo

---
 st.c | 4 ++++
 1 file changed, 4 insertions(+)
diff --git a/st.c b/st.c
index de2dd0e..51049ba 100644
--- a/st.c
+++ b/st.c
_AT_@ -2507,6 +2507,10 @@ check_control_code:
 	if (width == 2) {
 		gp->mode |= ATTR_WIDE;
 		if (term.c.x+1 < term.col) {
+			if (gp[1].mode == ATTR_WIDE && term.c.x+2 < term.col) {
+				gp[2].u = ' ';
+				gp[2].mode &= ~ATTR_WDUMMY;
+			}
 			gp[1].u = '\0';
 			gp[1].mode = ATTR_WDUMMY;
 		}
-- 
2.34.1

Received on Wed Dec 29 2021 - 18:07:17 CET