gen/getbsize.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1991, 1993
  27  *      The Regents of the University of California.  All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. All advertising materials mentioning features or use of this software
  38  *    must display the following acknowledgement:
  39  *      This product includes software developed by the University of
  40  *      California, Berkeley and its contributors.
  41  * 4. Neither the name of the University nor the names of its contributors
  42  *    may be used to endorse or promote products derived from this software
  43  *    without specific prior written permission.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  55  * SUCH DAMAGE.
  56  */
  57
  58
  59 #include <err.h>
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62 #include <string.h>
  63
  64 char *
  65 getbsize(headerlenp, blocksizep)
  66         int *headerlenp;
  67         long *blocksizep;
  68 {
  69         static char header[20];
  70         long n, max, mul, blocksize;
  71         char *ep, *p, *form;
  72
  73 #define KB      (1024L)
  74 #define MB      (1024L * 1024L)
  75 #define GB      (1024L * 1024L * 1024L)
  76 #define MAXB    GB              /* No tera, peta, nor exa. */
  77         form = "";
  78         if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') {
  79                 if ((n = strtol(p, &ep, 10)) < 0)
  80                         goto underflow;
  81                 if (n == 0)
  82                         n = 1;
  83                 if (*ep && ep[1])
  84                         goto fmterr;
  85                 switch (*ep) {
  86                 case 'G': case 'g':
  87                         form = "G";
  88                         max = MAXB / GB;
  89                         mul = GB;
  90                         break;
  91                 case 'K': case 'k':
  92                         form = "K";
  93                         max = MAXB / KB;
  94                         mul = KB;
  95                         break;
  96                 case 'M': case 'm':
  97                         form = "M";
  98                         max = MAXB / MB;
  99                         mul = MB;
 100                         break;
 101                 case '\0':
 102                         max = MAXB;
 103                         mul = 1;
 104                         break;
 105                 default:
 106 fmterr:                 warnx("%s: unknown blocksize", p);
 107                         n = 512;
 108                         mul = 1;
 109                         break;
 110                 }
 111                 if (n > max) {
 112                         warnx("maximum blocksize is %dG", MAXB / GB);
 113                         n = max;
 114                 }
 115                 if ((blocksize = n * mul) < 512) {
 116 underflow:              warnx("minimum blocksize is 512");
 117                         form = "";
 118                         blocksize = n = 512;
 119                 }
 120         } else
 121                 blocksize = n = 512;
 122
 123         (void)snprintf(header, sizeof(header), "%d%s-blocks", n, form);
 124         *headerlenp = strlen(header);
 125         *blocksizep = blocksize;
 126         return (header);
 127 }