newlib/libc/stdio/vswprintf.c

   1 /*
   2  * Copyright (c) 1990 The Regents of the University of California.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms are permitted
   6  * provided that the above copyright notice and this paragraph are
   7  * duplicated in all such forms and that any documentation,
   8  * and/or other materials related to such
   9  * distribution and use acknowledge that the software was developed
  10  * by the University of California, Berkeley.  The name of the
  11  * University may not be used to endorse or promote products derived
  12  * from this software without specific prior written permission.
  13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  16  */
  17 /* doc in vfwprintf.c */
  18
  19 #if defined(LIBC_SCCS) && !defined(lint)
  20 static char sccsid[] = "%W% (Berkeley) %G%";
  21 #endif /* LIBC_SCCS and not lint */
  22
  23 #include <_ansi.h>
  24 #include <reent.h>
  25 #include <stdio.h>
  26 #include <wchar.h>
  27 #include <limits.h>
  28 #include <stdarg.h>
  29 #include <errno.h>
  30
  31 #include "local.h"
  32
  33 int
  34 _vswprintf_r (struct _reent *ptr,
  35        wchar_t *str,
  36        size_t size,
  37        const wchar_t *fmt,
  38        va_list ap)
  39 {
  40   int ret;
  41   FILE f;
  42
  43   if (size > INT_MAX / sizeof (wchar_t))
  44     {
  45       _REENT_ERRNO(ptr) = EOVERFLOW;    /* POSIX extension */
  46       return EOF;
  47     }
  48   f._flags = __SWR | __SSTR;
  49   f._flags2 = 0;
  50   f._bf._base = f._p = (unsigned char *) str;
  51   f._bf._size = f._w = (size > 0 ? (size - 1) * sizeof (wchar_t) : 0);
  52   f._file = -1;  /* No file. */
  53   ret = _svfwprintf_r (ptr, &f, fmt, ap);
  54   /* _svfwprintf_r() does not put in a terminating NUL, so add one if
  55    * appropriate, which is whenever size is > 0.  _svfwprintf_r() stops
  56    * after n-1, so always just put at the end.  */
  57   if (size > 0)  {
  58     *(wchar_t *)f._p = L'\0';   /* terminate the string */
  59   }
  60   if(ret >= size)  {
  61     /* _svfwprintf_r() returns how many wide characters it would have printed
  62      * if there were enough space.  Return an error if too big to fit in str,
  63      * unlike snprintf, which returns the size needed.  */
  64     _REENT_ERRNO(ptr) = EOVERFLOW;      /* POSIX extension */
  65     ret = -1;
  66   }
  67   return ret;
  68 }
  69
  70 #ifndef _REENT_ONLY
  71
  72 int
  73 vswprintf (wchar_t *__restrict str,
  74        size_t size,
  75        const wchar_t *__restrict fmt,
  76        va_list ap)
  77 {
  78   return _vswprintf_r (_REENT, str, size, fmt, ap);
  79 }
  80
  81 #endif /* !_REENT_ONLY */