newlib/libc/stdio/vsniprintf.c

   1 /*
   2  * Copyright (c) 1990, 2007 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 viprintf.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 <limits.h>
  27 #include <stdarg.h>
  28 #include <errno.h>
  29
  30 #include "local.h"
  31
  32 #ifndef _REENT_ONLY
  33
  34 int
  35 vsniprintf (char *str,
  36        size_t size,
  37        const char *fmt,
  38        va_list ap)
  39 {
  40   return _vsniprintf_r (_REENT, str, size, fmt, ap);
  41 }
  42
  43 #endif /* !_REENT_ONLY */
  44
  45 int
  46 _vsniprintf_r (struct _reent *ptr,
  47        char *str,
  48        size_t size,
  49        const char *fmt,
  50        va_list ap)
  51 {
  52   int ret;
  53   FILE f;
  54
  55   if (size > INT_MAX)
  56     {
  57       _REENT_ERRNO(ptr) = EOVERFLOW;
  58       return EOF;
  59     }
  60   f._flags = __SWR | __SSTR;
  61   f._flags2 = 0;
  62   f._bf._base = f._p = (unsigned char *) str;
  63   f._bf._size = f._w = (size > 0 ? size - 1 : 0);
  64   f._file = -1;  /* No file. */
  65   ret = _svfiprintf_r (ptr, &f, fmt, ap);
  66   if (ret < EOF)
  67     _REENT_ERRNO(ptr) = EOVERFLOW;
  68   if (size > 0)
  69     *f._p = 0;
  70   return ret;
  71 }