usr/src/lib/libast/common/stdio/vswprintf.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23
  24 #include "stdhdr.h"
  25
  26 int
  27 vswprintf(wchar_t* s, size_t n, const wchar_t* fmt, va_list args)
  28 {
  29         Sfio_t  f;
  30         int     v;
  31
  32         if (!s)
  33                 return -1;
  34
  35         /*
  36          * make a fake stream
  37          */
  38
  39         SFCLEAR(&f, NiL);
  40         f.flags = SF_STRING|SF_WRITE;
  41         f.bits = SF_PRIVATE;
  42         f.mode = SF_WRITE;
  43         f.size = n - 1;
  44         f.data = f.next = f.endr = (uchar*)s;
  45         f.endb = f.endw = f.data + f.size;
  46
  47         /*
  48          * call and adjust
  49          */
  50
  51         v = vfwprintf(&f, fmt, args);
  52         *f.next = 0;
  53         _Sfi = f.next - f.data;
  54         return v;
  55 }