xref: /csrg-svn/lib/libc/gen/getbsize.c (revision 52780)
1 /*-
2  * Copyright (c) 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char sccsid[] = "@(#)getbsize.c	5.1 (Berkeley) 03/01/92";
10 #endif /* not lint */
11 
12 #include <stdio.h>
13 #include <stdlib.h>
14 
15 char *
16 getbsize(prog, headerlenp, blocksizep)
17 	char *prog;
18 	int *headerlenp, *blocksizep;
19 {
20 	static char header[20];
21 	long blocksize;
22 	char *ep, *p;
23 
24 #define	Kb	1024
25 #define	Mb	1048576
26 #define	Gb	1073741824
27 	if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') {
28 		blocksize = strtol(p, &ep, 10);
29 		switch(*ep) {
30 		case 'G': case 'g':
31 			if (ep[1])
32 				goto fmterr;
33 			if (blocksize > 1)
34 				goto overflow;
35 			*headerlenp = snprintf(header, sizeof(header),
36 			    "%dG-blocks", blocksize);
37 			*blocksizep = blocksize * Gb;
38 			return (header);
39 		case 'M': case 'm':
40 			if (ep[1])
41 				goto fmterr;
42 			*headerlenp = snprintf(header, sizeof(header),
43 			    "%dM-blocks", blocksize);
44 			*blocksizep = blocksize * Mb;
45 			return (header);
46 		case 'K': case 'k':
47 			if (ep[1])
48 				goto fmterr;
49 			*headerlenp = snprintf(header, sizeof(header),
50 			    "%dK-blocks", blocksize);
51 			*blocksizep = blocksize * Kb;
52 			return (header);
53 		case '\0':
54 			if (blocksize > Gb) {
55 overflow:			(void)fprintf(stderr,
56 				    "%s: maximum blocksize is 1G\n", prog);
57 				blocksize = 512;
58 			} else if (blocksize < 512) {
59 				(void)fprintf(stderr,
60 				    "%s: minimum blocksize is 512\n", prog);
61 				blocksize = 512;
62 			}
63 			break;
64 		default:
65 fmterr:			(void)fprintf(stderr,
66 			    "%s: %s: unknown blocksize\n", prog, p);
67 			blocksize = 512;
68 			break;
69 		}
70 	} else
71 		blocksize = 512;
72 
73 	*headerlenp = snprintf(header, sizeof(header), "%d-blocks", blocksize);
74 	*blocksizep = blocksize;
75 	return (header);
76 }
77