lib/libc/stdio/vasprintf.c

   1 /*      $OpenBSD: vasprintf.c,v 1.4 1998/06/21 22:13:47 millert Exp $   */
   2
   3 /*
   4  * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  19  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  20  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
  21  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  24  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  27  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/lib/libc/stdio/vasprintf.c,v 1.19 2008/04/17 22:17:54 jhb Exp $
  30  * $DragonFly: src/lib/libc/stdio/vasprintf.c,v 1.8 2006/03/02 18:05:30 joerg Exp $
  31  */
  32
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <errno.h>
  36 #include "local.h"
  37 #include "priv_stdio.h"
  38
  39 int
  40 vasprintf(char **str, const char *fmt, __va_list ap)
  41 {
  42         int ret;
  43         FILE f;
  44
  45         f.pub._fileno = -1;
  46         f.pub._flags = __SWR | __SSTR | __SALC;
  47         f._bf._base = f.pub._p = (unsigned char *)malloc(128);
  48         if (f._bf._base == NULL) {
  49                 *str = NULL;
  50                 errno = ENOMEM;
  51                 return (-1);
  52         }
  53         f._bf._size = f.pub._w = 127;           /* Leave room for the NUL */
  54         memset(WCIO_GET(&f), 0, sizeof(struct wchar_io_data));
  55         ret = __vfprintf(&f, fmt, ap);
  56         if (ret < 0) {
  57                 free(f._bf._base);
  58                 *str = NULL;
  59                 errno = ENOMEM;
  60                 return (-1);
  61         }
  62         *f.pub._p = '\0';
  63         *str = (char *)f._bf._base;
  64         return (ret);
  65 }