/*      Id: compat_strtonum.c,v 1.2 2020/06/15 01:37:15 schwarze Exp    */
/*      $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 "config.h"

#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);
}