1/* $NetBSD: getbsize.c,v 1.17 2012/06/25 22:32:43 abs 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. 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#if defined(LIBC_SCCS) && !defined(lint) 34#if 0 35static char sccsid[] = "@(#)getbsize.c 8.1 (Berkeley) 6/4/93"; 36#else 37__RCSID("$NetBSD: getbsize.c,v 1.17 2012/06/25 22:32:43 abs Exp $"); 38#endif 39#endif /* not lint */ 40 41#include "namespace.h" 42 43#include <assert.h> 44#include <err.h> 45#include <stdio.h> 46#include <stdlib.h> 47#include <string.h> 48 49#ifdef __weak_alias 50__weak_alias(getbsize,_getbsize) 51#endif 52 53char * 54getbsize(int *headerlenp, long *blocksizep) 55{ 56 static char header[20]; 57 long n, max, mul, blocksize; 58 char *ep, *p; 59 const char *form; 60 61#define KB (1024L) 62#define MB (1024L * 1024L) 63#define GB (1024L * 1024L * 1024L) 64#define MAXB GB /* No tera, peta, nor exa. */ 65 form = ""; 66 if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') { 67 if ((n = strtol(p, &ep, 10)) < 0) 68 goto underflow; 69 if (n == 0) 70 n = 1; 71 if (*ep && ep[1]) 72 goto fmterr; 73 switch (*ep) { 74 case 'G': case 'g': 75 form = "G"; 76 max = MAXB / GB; 77 mul = GB; 78 break; 79 case 'K': case 'k': 80 form = "K"; 81 max = MAXB / KB; 82 mul = KB; 83 break; 84 case 'M': case 'm': 85 form = "M"; 86 max = MAXB / MB; 87 mul = MB; 88 break; 89 case '\0': 90 max = MAXB; 91 mul = 1; 92 break; 93 default: 94fmterr: warnx("%s: unknown blocksize", p); 95 n = 512; 96 mul = 1; 97 max = 0; 98 break; 99 } 100 if (n > max) { 101 warnx("maximum blocksize is %ldG", MAXB / GB); 102 n = max; 103 } 104 if ((blocksize = n * mul) < 512) { 105underflow: warnx("%s: minimum blocksize is 512", p); 106 form = ""; 107 blocksize = n = 512; 108 } 109 } else 110 blocksize = n = 512; 111 112 if (headerlenp) 113 *headerlenp = 114 snprintf(header, sizeof(header), "%ld%s-blocks", n, form); 115 if (blocksizep) 116 *blocksizep = blocksize; 117 return (header); 118} 119