Replace buggy for-loops to skip certain character with strspn(). If *fmt was

'\0' (eg in the invocation 'printf %'), the for-loop would miss the terminating
null character.

MFC after:	1 week

1 files changed, 3 insertions, 3 deletions

diff --git a/usr.bin/printf/printf.c b/usr.bin/printf/printf.c
index 64206a4..64aa07a 100644
--- a/usr.bin/printf/printf.c
+++ b/usr.bin/printf/printf.c
@@ -179,7 +179,7 @@ next:		for (start = fmt;; ++fmt) {
 		}
 
 		/* skip to field width */
-		for (; strchr(skip1, *fmt); ++fmt);
+		fmt += strspn(fmt, skip1);
 		if (*fmt == '*') {
 			if (getint(&fieldwidth))
 				return (1);
@@ -189,7 +189,7 @@ next:		for (start = fmt;; ++fmt) {
 			havewidth = 0;
 
 			/* skip to possible '.', get following precision */
-			for (; strchr(skip2, *fmt); ++fmt);
+			fmt += strspn(fmt, skip2);
 		}
 		if (*fmt == '.') {
 			/* precision present? */
@@ -203,7 +203,7 @@ next:		for (start = fmt;; ++fmt) {
 				haveprec = 0;
 
 				/* skip to conversion char */
-				for (; strchr(skip2, *fmt); ++fmt);
+				fmt += strspn(fmt, skip2);
 			}
 		} else
 			haveprec = 0;