1 /* $NetBSD: getbsize.c,v 1.13 2000/01/22 22:19:10 mycroft Exp $ */ 2 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)getbsize.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: getbsize.c,v 1.13 2000/01/22 22:19:10 mycroft Exp $"); 42 #endif 43 #endif /* not lint */ 44 45 #include "namespace.h" 46 47 #include <assert.h> 48 #include <err.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 53 #ifdef __weak_alias 54 __weak_alias(getbsize,_getbsize) 55 #endif 56 57 char * 58 getbsize(headerlenp, blocksizep) 59 int *headerlenp; 60 long *blocksizep; 61 { 62 static char header[20]; 63 long n, max, mul, blocksize; 64 char *ep, *p, *form; 65 66 _DIAGASSERT(headerlenp != NULL); 67 _DIAGASSERT(blocksizep != NULL); 68 69 #define KB (1024L) 70 #define MB (1024L * 1024L) 71 #define GB (1024L * 1024L * 1024L) 72 #define MAXB GB /* No tera, peta, nor exa. */ 73 form = ""; 74 if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') { 75 if ((n = strtol(p, &ep, 10)) < 0) 76 goto underflow; 77 if (n == 0) 78 n = 1; 79 if (*ep && ep[1]) 80 goto fmterr; 81 switch (*ep) { 82 case 'G': case 'g': 83 form = "G"; 84 max = MAXB / GB; 85 mul = GB; 86 break; 87 case 'K': case 'k': 88 form = "K"; 89 max = MAXB / KB; 90 mul = KB; 91 break; 92 case 'M': case 'm': 93 form = "M"; 94 max = MAXB / MB; 95 mul = MB; 96 break; 97 case '\0': 98 max = MAXB; 99 mul = 1; 100 break; 101 default: 102 fmterr: warnx("%s: unknown blocksize", p); 103 n = 512; 104 mul = 1; 105 max = 0; 106 break; 107 } 108 if (n > max) { 109 warnx("maximum blocksize is %ldG", MAXB / GB); 110 n = max; 111 } 112 if ((blocksize = n * mul) < 512) { 113 underflow: warnx("%s: minimum blocksize is 512", p); 114 form = ""; 115 blocksize = n = 512; 116 } 117 } else 118 blocksize = n = 512; 119 120 *headerlenp = snprintf(header, sizeof(header), "%ld%s-blocks", n, form); 121 *blocksizep = blocksize; 122 return (header); 123 } 124