freebsd-skq/sys/libkern/asprintf.c
rstone 96dd7966e7 Implement asprintf in libkern
Differential Revision:		https://reviews.freebsd.org/D1877
Reviewed by:			pjd, jfv
MFC After:			1 month
Sponsored by:			Sandvine Inc.
2015-03-01 00:22:16 +00:00

78 lines
2.2 KiB
C

/*-
* Copyright (c) 2013-2015 Sandvine Inc. All rights reserved.
* 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 AUTHOR 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 AUTHOR 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <machine/stdarg.h>
int
vasprintf(char **buf, struct malloc_type *mtp, const char *format, va_list va)
{
int len, ret;
va_list tmp_va;
char dummy;
va_copy(tmp_va, va);
len = vsnprintf(&dummy, 0, format, tmp_va);
va_end(tmp_va);
if (len < 0) {
*buf = NULL;
return (len);
}
/* Account for null terminator. */
len += 1;
*buf = malloc(len, mtp, M_NOWAIT);
if (*buf == NULL)
return (-1);
ret = vsnprintf(*buf, len, format, va);
if (ret < 0) {
free(*buf, mtp);
*buf = NULL;
}
return (ret);
}
int
asprintf(char **buf, struct malloc_type *mtp, const char *format, ...)
{
int ret;
va_list va;
va_start(va, format);
ret = vasprintf(buf, mtp, format, va);
va_end(va);
return (ret);
}