1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __SCCSID("@(#)getbsize.c 8.1 (Berkeley) 6/4/93");
34 __FBSDID("$FreeBSD$");
35
36 #include <err.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40
41 char *
getbsize(int * headerlenp,long * blocksizep)42 getbsize(int *headerlenp, long *blocksizep)
43 {
44 static char header[20];
45 long n, max, mul, blocksize;
46 char *ep, *p;
47 const char *form;
48
49 #define KB (1024L)
50 #define MB (1024L * 1024L)
51 #define GB (1024L * 1024L * 1024L)
52 #define MAXB GB /* No tera, peta, nor exa. */
53 form = "";
54 if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') {
55 if ((n = strtol(p, &ep, 10)) < 0)
56 goto underflow;
57 if (n == 0)
58 n = 1;
59 if (*ep && ep[1])
60 goto fmterr;
61 switch (*ep) {
62 case 'G': case 'g':
63 form = "G";
64 max = MAXB / GB;
65 mul = GB;
66 break;
67 case 'K': case 'k':
68 form = "K";
69 max = MAXB / KB;
70 mul = KB;
71 break;
72 case 'M': case 'm':
73 form = "M";
74 max = MAXB / MB;
75 mul = MB;
76 break;
77 case '\0':
78 max = MAXB;
79 mul = 1;
80 break;
81 default:
82 fmterr: warnx("%s: unknown blocksize", p);
83 n = 512;
84 max = MAXB;
85 mul = 1;
86 break;
87 }
88 if (n > max) {
89 warnx("maximum blocksize is %ldG", MAXB / GB);
90 n = max;
91 }
92 if ((blocksize = n * mul) < 512) {
93 underflow: warnx("minimum blocksize is 512");
94 form = "";
95 blocksize = n = 512;
96 }
97 } else
98 blocksize = n = 512;
99
100 (void)snprintf(header, sizeof(header), "%ld%s-blocks", n, form);
101 *headerlenp = strlen(header);
102 *blocksizep = blocksize;
103 return (header);
104 }
105