stdio/FreeBSD/vsnprintf.c

   1 /*-
   2  * Copyright (c) 1990, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Chris Torek.
   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  * 4. 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
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 static char sccsid[] = "@(#)vsnprintf.c 8.1 (Berkeley) 6/4/93";
  35 #endif /* LIBC_SCCS and not lint */
  36 #include <sys/cdefs.h>
  37 __FBSDID("$FreeBSD: src/lib/libc/stdio/vsnprintf.c,v 1.24 2008/04/17 22:17:54 jhb Exp $");
  38
  39 #include "xlocale_private.h"
  40
  41 #include <limits.h>
  42 #include <stdio.h>
  43 #include "local.h"
  44
  45 __private_extern__ int
  46 _vsnprintf(printf_comp_t __restrict pc, printf_domain_t __restrict domain, char * __restrict str, size_t n, locale_t __restrict loc, const char * __restrict fmt, __va_list ap)
  47 {
  48         size_t on;
  49         int ret;
  50         char dummy[2];
  51         FILE f;
  52         struct __sFILEX ext;
  53         f._extra = &ext;
  54         INITEXTRA(&f);
  55
  56         on = n;
  57         if (n != 0)
  58                 n--;
  59         if (n > INT_MAX)
  60                 n = INT_MAX;
  61         /* Stdio internals do not deal correctly with zero length buffer */
  62         if (n == 0) {
  63                 if (on > 0)
  64                         *str = '\0';
  65                 str = dummy;
  66                 n = 1;
  67         }
  68         f._file = -1;
  69         f._flags = __SWR | __SSTR;
  70         f._bf._base = f._p = (unsigned char *)str;
  71         f._bf._size = f._w = n;
  72         f._orientation = 0;
  73         memset(&f._mbstate, 0, sizeof(mbstate_t));
  74         ret = __v2printf(pc, domain, &f, loc, fmt, ap);
  75         if (on > 0)
  76                 *f._p = '\0';
  77         return (ret);
  78 }
  79 int
  80 vsnprintf_l(char * __restrict str, size_t n, locale_t __restrict loc, const char * __restrict fmt,
  81     __va_list ap)
  82 {
  83         return _vsnprintf(XPRINTF_PLAIN, NULL, str, n, loc, fmt, ap);
  84 }
  85
  86 int
  87 vsnprintf(char * __restrict str, size_t n, const char * __restrict fmt,
  88     __va_list ap)
  89 {
  90         return _vsnprintf(XPRINTF_PLAIN, NULL, str, n, __current_locale(), fmt, ap);
  91 }