minix/lib/libc/stdio/asprintf.c

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/* $NetBSD: asprintf.c,v 1.2 2007/07/20 00:10:06 tnn Exp $ */
/*-
* Copyright (c) 2007 Joerg Sonnenberger <joerg@NetBSD.org>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
int
asprintf(char **ret, const char *fmt, ...)
{
va_list ap;
int retval;
va_start(ap, fmt);
retval = vasprintf(ret, fmt, ap);
va_end(ap);
return retval;
}
int
vasprintf(char **ret, const char *fmt, va_list ap)
{
char *buf, *new_buf;
size_t len;
int retval;
len = 128;
buf = malloc(len);
if (buf == NULL) {
*ret = NULL;
return -1;
}
retval = vsnprintf(buf, len, fmt, ap);
if (retval < 0) {
free(buf);
*ret = NULL;
return -1;
}
if (retval < len) {
new_buf = realloc(buf, retval + 1);
if (new_buf == NULL)
*ret = buf;
else
*ret = new_buf;
return retval;
}
len = (size_t)retval + 1;
free(buf);
buf = malloc(len);
if (buf == NULL) {
*ret = NULL;
return -1;
}
retval = vsnprintf(buf, len, fmt, ap);
if (retval != len - 1) {
free(buf);
*ret = NULL;
return -1;
}
*ret = buf;
return retval;
}