1 /* $NetBSD: vsnprintf.c,v 1.20 2005/02/09 21:35:47 kleink 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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)vsnprintf.c 8.1 (Berkeley) 6/4/93"; 39 #else 40 __RCSID("$NetBSD: vsnprintf.c,v 1.20 2005/02/09 21:35:47 kleink Exp $"); 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include "namespace.h" 45 46 #include <assert.h> 47 #include <errno.h> 48 #include <stdio.h> 49 #include "reentrant.h" 50 #include "local.h" 51 52 #ifdef __weak_alias 53 __weak_alias(vsnprintf,_vsnprintf) 54 #endif 55 56 int 57 vsnprintf(str, n, fmt, ap) 58 char *str; 59 size_t n; 60 const char *fmt; 61 _BSD_VA_LIST_ ap; 62 { 63 int ret; 64 FILE f; 65 struct __sfileext fext; 66 unsigned char dummy[1]; 67 68 _DIAGASSERT(n == 0 || str != NULL); 69 _DIAGASSERT(fmt != NULL); 70 71 if ((int)n < 0) { 72 errno = EINVAL; 73 return (-1); 74 } 75 76 _FILEEXT_SETUP(&f, &fext); 77 f._file = -1; 78 f._flags = __SWR | __SSTR; 79 if (n == 0) { 80 f._bf._base = f._p = dummy; 81 f._bf._size = f._w = 0; 82 } else { 83 f._bf._base = f._p = (unsigned char *)str; 84 f._bf._size = f._w = n - 1; 85 } 86 ret = __vfprintf_unlocked(&f, fmt, ap); 87 *f._p = 0; 88 return (ret); 89 } 90