/*      $OpenBSD: strtonum.c,v 1.8 2015/09/13 08:31:48 guenther Exp $   */

/*
 * Copyright (c) 2004 Ted Unangst and Todd Miller
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <errno.h>
#include <limits.h>
#include <stdlib.h>

#define INVALID         1
#define TOOSMALL        2
#define TOOLARGE        3

long long
strtonum(const char *numstr, long long minval, long long maxval,
    const char **errstrp)
{
        long long ll = 0;
        int error = 0;
        char *ep;
        struct errval {
                const char *errstr;
                int err;
        } ev[4] = {
                { NULL,         0 },
                { "invalid",    EINVAL },
                { "too small",  ERANGE },
                { "too large",  ERANGE },
        };

        ev[0].err = errno;
        errno = 0;
        if (minval > maxval) {
                error = INVALID;
        } else {
                ll = strtoll(numstr, &ep, 10);
                if (numstr == ep || *ep != '\0')
                        error = INVALID;
                else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
                        error = TOOSMALL;
                else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval)
                        error = TOOLARGE;
        }
        if (errstrp != NULL)
                *errstrp = ev[error].errstr;
        errno = ev[error].err;
        if (error)
                ll = 0;

        return (ll);
}
DEF_WEAK(strtonum);