1 /* $NetBSD: vsnprintf.c,v 1.18 2003/01/18 11:29:59 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Chris Torek. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)vsnprintf.c 8.1 (Berkeley) 6/4/93"; 43 #else 44 __RCSID("$NetBSD: vsnprintf.c,v 1.18 2003/01/18 11:29:59 thorpej Exp $"); 45 #endif 46 #endif /* LIBC_SCCS and not lint */ 47 48 #include "namespace.h" 49 50 #include <assert.h> 51 #include <errno.h> 52 #include <stdio.h> 53 #include "reentrant.h" 54 #include "local.h" 55 56 #ifdef __weak_alias 57 __weak_alias(vsnprintf,_vsnprintf) 58 #endif 59 60 int 61 vsnprintf(str, n, fmt, ap) 62 char *str; 63 size_t n; 64 const char *fmt; 65 _BSD_VA_LIST_ ap; 66 { 67 int ret; 68 FILE f; 69 struct __sfileext fext; 70 unsigned char dummy[1]; 71 72 _DIAGASSERT(n == 0 || str != NULL); 73 _DIAGASSERT(fmt != NULL); 74 75 if ((int)n < 0) { 76 errno = EINVAL; 77 return (-1); 78 } 79 80 _FILEEXT_SETUP(&f, &fext); 81 f._file = -1; 82 f._flags = __SWR | __SSTR; 83 if (n == 0) { 84 f._bf._base = f._p = dummy; 85 f._bf._size = f._w = 0; 86 } else { 87 f._bf._base = f._p = (unsigned char *)str; 88 f._bf._size = f._w = n - 1; 89 } 90 ret = vfprintf_unlocked(&f, fmt, ap); 91 *f._p = 0; 92 return (ret); 93 } 94