[PATCH 1/1] paint visual host key with unicode box-drawing characters

[Christian Hesse]

From: Christian Hesse <mail at eworm.de>

Signed-off-by: Christian Hesse <mail at eworm.de>
---
 sshkey.c | 47 ++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 36 insertions(+), 11 deletions(-)

diff --git a/sshkey.c b/sshkey.c
index cfe5980..47511c2 100644
--- a/sshkey.c
+++ b/sshkey.c
@@ -44,6 +44,9 @@
 #include <stdio.h>
 #include <string.h>
 #include <resolv.h>
+#ifdef HAVE_LOCALE_H
+#include <locale.h>
+#endif /* HAVE_LOCALE_H */
 #ifdef HAVE_UTIL_H
 #include <util.h>
 #endif /* HAVE_UTIL_H */
@@ -1088,6 +1091,12 @@ fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
 	 * Chars to be used after each other every time the worm
 	 * intersects with itself.  Matter of taste.
 	 */
+#ifdef HAVE_LOCALE_H
+	char    *locale;
+	char    *border_utf8[]  = { "┏", "━", "┓", "┃", "┗", "┛" };
+#endif
+	char    *border_ascii[] = { "+", "-", "+", "|", "+", "+" };
+	char   **border;
 	char	*augmentation_string = " .o+=*BOX@%&#/^SE";
 	char	*retval, *p, title[FLDSIZE_X], hash[FLDSIZE_X];
 	u_char	 field[FLDSIZE_X][FLDSIZE_Y];
@@ -1096,9 +1105,25 @@ fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
 	int	 x, y, r;
 	size_t	 len = strlen(augmentation_string) - 1;
 
-	if ((retval = calloc((FLDSIZE_X + 3), (FLDSIZE_Y + 2))) == NULL)
+	if ((retval = malloc((FLDSIZE_X + 7) * FLDSIZE_Y + FLDSIZE_X * 3 * 2)) == NULL)
 		return NULL;
 
+#ifdef HAVE_LOCALE_H
+	/* initialize locale */
+	setlocale(LC_ALL, "");
+
+	/* get locale for LC_CTYPE and decide about characters to use */
+	locale = setlocale(LC_CTYPE, NULL);
+	if (locale != NULL && *locale != 0 &&
+			(strstr(locale, "UTF-8") ||
+			 strstr(locale, "utf-8") ||
+			 strstr(locale, "UTF8")  ||
+			 strstr(locale, "utf8")))
+		border = border_utf8;
+	else
+#endif
+		border = border_ascii;
+
 	/* initialize field */
 	memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
 	x = FLDSIZE_X / 2;
@@ -1145,34 +1170,34 @@ fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
 
 	/* output upper border */
 	p = retval;
-	*p++ = '+';
+	p += sprintf(p, "%s", border[0]);
 	for (i = 0; i < (FLDSIZE_X - tlen) / 2; i++)
-		*p++ = '-';
+		p += sprintf(p, "%s", border[1]);
 	memcpy(p, title, tlen);
 	p += tlen;
 	for (i += tlen; i < FLDSIZE_X; i++)
-		*p++ = '-';
-	*p++ = '+';
+		p += sprintf(p, "%s", border[1]);
+	p += sprintf(p, "%s", border[2]);
 	*p++ = '\n';
 
 	/* output content */
 	for (y = 0; y < FLDSIZE_Y; y++) {
-		*p++ = '|';
+		p += sprintf(p, "%s", border[3]);
 		for (x = 0; x < FLDSIZE_X; x++)
 			*p++ = augmentation_string[MIN(field[x][y], len)];
-		*p++ = '|';
+		p += sprintf(p, "%s", border[3]);
 		*p++ = '\n';
 	}
 
 	/* output lower border */
-	*p++ = '+';
+	p += sprintf(p, "%s", border[4]);
 	for (i = 0; i < (FLDSIZE_X - hlen) / 2; i++)
-		*p++ = '-';
+		p += sprintf(p, "%s", border[1]);
 	memcpy(p, hash, hlen);
 	p += hlen;
 	for (i += hlen; i < FLDSIZE_X; i++)
-		*p++ = '-';
-	*p++ = '+';
+		p += sprintf(p, "%s", border[1]);
+	p += sprintf(p, "%s", border[5]);
 
 	return retval;
 }
-- 
2.4.5