lib/libc/stdio/vasprintf.c

   1 /*      $NetBSD: vasprintf.c,v 1.17 2013/05/19 21:45:00 christos 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
  30 #include <sys/cdefs.h>
  31 #if defined(LIBC_SCCS) && !defined(lint)
  32 __RCSID("$NetBSD: vasprintf.c,v 1.17 2013/05/19 21:45:00 christos Exp $");
  33 #endif /* LIBC_SCCS and not lint */
  34
  35 #include "namespace.h"
  36
  37 #include <assert.h>
  38 #include <errno.h>
  39 #include <locale.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42
  43 #include "reentrant.h"
  44 #include "setlocale_local.h"
  45 #include "local.h"
  46
  47 __weak_alias(asprintf, _asprintf)
  48 __weak_alias(asprintf_l, _asprintf_l)
  49 __weak_alias(vasprintf, _vasprintf)
  50 __weak_alias(vasprintf_l, _vasprintf_l)
  51
  52 int
  53 vasprintf_l(char **str, locale_t loc, const char *fmt, va_list ap)
  54 {
  55         int ret;
  56         FILE f;
  57         struct __sfileext fext;
  58         unsigned char *_base;
  59
  60         _DIAGASSERT(str != NULL);
  61         _DIAGASSERT(fmt != NULL);
  62
  63         _FILEEXT_SETUP(&f, &fext);
  64         f._file = -1;
  65         f._flags = __SWR | __SSTR | __SALC;
  66         f._bf._base = f._p = malloc(128);
  67         if (f._bf._base == NULL)
  68                 goto err;
  69         f._bf._size = f._w = 127;               /* Leave room for the NUL */
  70         ret = __vfprintf_unlocked_l(&f, loc, fmt, ap);
  71         if (ret == -1)
  72                 goto err;
  73         *f._p = '\0';
  74         _base = realloc(f._bf._base, (size_t)(ret + 1));
  75         if (_base == NULL)
  76                 goto err;
  77         *str = (char *)_base;
  78         return ret;
  79
  80 err:
  81         if (f._bf._base)
  82                 free(f._bf._base);
  83         *str = NULL;
  84         errno = ENOMEM;
  85         return -1;
  86 }
  87
  88 int
  89 vasprintf(char **str, const char *fmt, va_list ap)
  90 {
  91         return vasprintf_l(str, _current_locale(), fmt, ap);
  92 }
  93
  94 int
  95 asprintf_l(char **str, locale_t loc, char const *fmt, ...)
  96 {
  97         va_list ap;
  98         int ret;
  99
 100         va_start(ap, fmt);
 101         ret = vasprintf_l(str, loc, fmt, ap);
 102         va_end(ap);
 103         return ret;
 104 }
 105
 106 int
 107 asprintf(char **str, char const *fmt, ...)
 108 {
 109         va_list ap;
 110         int ret;
 111
 112         va_start(ap, fmt);
 113         ret = vasprintf(str, fmt, ap);
 114         va_end(ap);
 115         return ret;
 116 }