freebsd-src/usr.sbin/pw/strtounum.c

/*-
 * Copyright (C) 2015 Baptiste Daroussin <bapt@FreeBSD.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
 *    in this position and unchanged.
 * 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(S) ``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(S) 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>
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stdlib.h>

#include "pw.h"

uintmax_t
strtounum(const char * __restrict np, uintmax_t minval, uintmax_t maxval,
    const char ** __restrict errpp)
{
	char *endp;
	uintmax_t ret;

	*errpp = NULL;
	if (minval > maxval) {
		errno = EINVAL;
		*errpp = "invalid";
		return (0);
	}
	errno = 0;
	ret = strtoumax(np, &endp, 10);
	if (endp == np || *endp != '\0') {
		errno = EINVAL;
		*errpp = "invalid";
		return (0);
	}
	if (ret < minval) {
		errno = ERANGE;
		*errpp = "too small";
		return (0);
	}
	if (errno == ERANGE || ret > maxval) {
		errno = ERANGE;
		*errpp = "too large";
		return (0);
	}
	return (ret);
}