1 /*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)getbsize.c 8.1 (Berkeley) 6/4/93
30 * $FreeBSD: src/lib/libc/gen/getbsize.c,v 1.9 2008/08/04 06:53:13 cperciva Exp $
31 * $DragonFly: src/lib/libc/gen/getbsize.c,v 1.4 2005/11/13 00:07:42 swildner Exp $
32 */
33
34 #include <err.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38
39 char *
getbsize(int * headerlenp,long * blocksizep)40 getbsize(int *headerlenp, long *blocksizep)
41 {
42 static char header[20];
43 long n, max, mul, blocksize;
44 char *ep, *p;
45 const char *form;
46
47 #define KB (1024L)
48 #define MB (1024L * 1024L)
49 #define GB (1024L * 1024L * 1024L)
50 #define MAXB GB /* No tera, peta, nor exa. */
51 form = "";
52 if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') {
53 if ((n = strtol(p, &ep, 10)) < 0)
54 goto underflow;
55 if (n == 0)
56 n = 1;
57 if (*ep && ep[1])
58 goto fmterr;
59 switch (*ep) {
60 case 'G': case 'g':
61 form = "G";
62 max = MAXB / GB;
63 mul = GB;
64 break;
65 case 'K': case 'k':
66 form = "K";
67 max = MAXB / KB;
68 mul = KB;
69 break;
70 case 'M': case 'm':
71 form = "M";
72 max = MAXB / MB;
73 mul = MB;
74 break;
75 case '\0':
76 max = MAXB;
77 mul = 1;
78 break;
79 default:
80 fmterr: warnx("%s: unknown blocksize", p);
81 n = 512;
82 max = MAXB;
83 mul = 1;
84 break;
85 }
86 if (n > max) {
87 warnx("maximum blocksize is %ldG", MAXB / GB);
88 n = max;
89 }
90 if ((blocksize = n * mul) < 512) {
91 underflow: warnx("minimum blocksize is 512");
92 form = "";
93 blocksize = n = 512;
94 }
95 } else
96 blocksize = n = 512;
97
98 snprintf(header, sizeof(header), "%ld%s-blocks", n, form);
99 *headerlenp = strlen(header);
100 *blocksizep = blocksize;
101 return (header);
102 }
103