stagit-gopher

commit 8091f757ce641307bcdc69c9e5348ef54ab82e5c
parent 70e0e50a6c4d83f7b809be4338bcf2868c13b49b
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Fri,  8 Jan 2021 14:30:44 +0100

stagit-gopher-index: sync utf8pad from stagit-gopher.c

Syncs a fix from commit e32410fe:
"fix truncation and padding for lines containing multiwidth glyphs"

Diffstat:
M
stagit-gopher-index.c
 | 
22
+++++++++++++---------

1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/stagit-gopher-index.c b/stagit-gopher-index.c
@@ -22,29 +22,33 @@ static char *name = "";
 int
 utf8pad(char *buf, size_t bufsiz, const char *s, size_t len, int pad)
 {
-	wchar_t w;
+	wchar_t wc;
 	size_t col = 0, i, slen, siz = 0;
-	int rl, wc;
+	int rl, w;
 
 	if (!len)
 		return -1;
 
 	slen = strlen(s);
-	for (i = 0; i < slen && col < len + 1; i += rl) {
-		if ((rl = mbtowc(&w, &s[i], slen - i < 4 ? slen - i : 4)) <= 0)
+	for (i = 0; i < slen; i += rl) {
+		if ((rl = mbtowc(&wc, &s[i], slen - i < 4 ? slen - i : 4)) <= 0)
 			break;
-		if ((wc = wcwidth(w)) == -1)
-			wc = 1;
-		col += wc;
-		if (col >= len && s[i + rl]) {
+		if ((w = wcwidth(wc)) == -1)
+			continue;
+		if (col + w > len || (col + w == len && s[i + rl])) {
 			if (siz + 4 >= bufsiz)
 				return -1;
-			memcpy(&buf[siz], "\xe2\x80\xa6", 4);
+			memcpy(&buf[siz], "\xe2\x80\xa6", 3);
+			siz += 3;
+			if (col + w == len && w > 1)
+				buf[siz++] = pad;
+			buf[siz] = '\0';
 			return 0;
 		}
 		if (siz + rl + 1 >= bufsiz)
 			return -1;
 		memcpy(&buf[siz], &s[i], rl);
+		col += w;
 		siz += rl;
 		buf[siz] = '\0';
 	}