diff options
| -rw-r--r-- | lib/libc/stdio/snprintf.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/lib/libc/stdio/snprintf.c b/lib/libc/stdio/snprintf.c index 4b6c9202a2d..ab44d6128d9 100644 --- a/lib/libc/stdio/snprintf.c +++ b/lib/libc/stdio/snprintf.c @@ -31,7 +31,7 @@ */ #if defined(LIBC_SCCS) && !defined(lint) -static char rcsid[] = "$OpenBSD: snprintf.c,v 1.8 2003/06/02 20:18:37 millert Exp $"; +static char rcsid[] = "$OpenBSD: snprintf.c,v 1.9 2004/04/10 19:34:44 millert Exp $"; #endif /* LIBC_SCCS and not lint */ #include <limits.h> @@ -41,21 +41,26 @@ static char rcsid[] = "$OpenBSD: snprintf.c,v 1.8 2003/06/02 20:18:37 millert Ex int snprintf(char *str, size_t n, char const *fmt, ...) { - int ret; va_list ap; + int ret; + char dummy; FILE f; /* While snprintf(3) specifies size_t stdio uses an int internally */ if (n > INT_MAX) n = INT_MAX; + /* Stdio internals do not deal correctly with zero length buffer */ + if (n == 0) { + str = &dummy; + n = 1; + } va_start(ap, fmt); f._file = -1; f._flags = __SWR | __SSTR; f._bf._base = f._p = (unsigned char *)str; - f._bf._size = f._w = n ? n - 1 : 0; + f._bf._size = f._w = n - 1; ret = vfprintf(&f, fmt, ap); - if (n) - *f._p = '\0'; + *f._p = '\0'; va_end(ap); return (ret); } |