lib/libc/stdlib/strtonum.c

   1 /*      $NetBSD: strtonum.c,v 1.4 2015/03/10 12:57:56 christos Exp $    */
   2 /*-
   3  * Copyright (c) 2014 The NetBSD Foundation, Inc.
   4  * All rights reserved.
   5  *
   6  * This code is derived from software contributed to The NetBSD Foundation
   7  * by Christos Zoulas.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include <sys/cdefs.h>
  32 __RCSID("$NetBSD: strtonum.c,v 1.4 2015/03/10 12:57:56 christos Exp $");
  33
  34 #define _OPENBSD_SOURCE
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <errno.h>
  38 #include <inttypes.h>
  39
  40 long long
  41 strtonum(const char *nptr, long long minval, long long maxval,
  42          const char **errstr)
  43 {
  44         int e;
  45         long long rv;
  46         const char *resp;
  47
  48         if (errstr == NULL)
  49                 errstr = &resp;
  50
  51         rv = (long long)strtoi(nptr, NULL, 10, minval, maxval, &e);
  52
  53         if (e == 0) {
  54                 *errstr = NULL;
  55                 return rv;
  56         }
  57
  58         if (e == ERANGE)
  59                 *errstr = (rv == maxval ? "too large" : "too small");
  60         else
  61                 *errstr = "invalid";
  62
  63         return 0;
  64 }