1 /* $OpenBSD: snprintf.c,v 1.7 2019/05/11 16:56:47 deraadt Exp $ */ 2 /* $NetBSD: printf.c,v 1.10 1996/11/30 04:19:21 gwr Exp $ */ 3 4 /*- 5 * Copyright (c) 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)printf.c 8.1 (Berkeley) 6/11/93 33 */ 34 35 #include <sys/types.h> 36 #include <sys/stdarg.h> 37 38 #include "stand.h" 39 40 extern void kprintn(void (*)(int), u_long, int); 41 extern void kdoprnt(void (*)(int), const char *, va_list); 42 43 static void sputchar(int); 44 45 static char *sbuf, *sbuf_end; 46 47 void 48 sputchar(int c) 49 { 50 if (sbuf < sbuf_end) 51 *sbuf = c; 52 sbuf++; 53 } 54 55 int 56 snprintf(char *buf, size_t len, const char *fmt, ...) 57 { 58 va_list ap; 59 60 sbuf = buf; 61 sbuf_end = sbuf + len; 62 va_start(ap, fmt); 63 kdoprnt(sputchar, fmt, ap); 64 va_end(ap); 65 66 if (sbuf < sbuf_end) 67 *sbuf = '\0'; 68 else if (len > 0) 69 *(sbuf_end - 1) = '\0'; 70 71 return sbuf - buf; 72 } 73