1 /* $NetBSD: getbsize.c,v 1.16 2005/11/29 03:11:59 christos 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 35 static char sccsid[] = "@(#)getbsize.c 8.1 (Berkeley) 6/4/93"; 36 #else 37 __RCSID("$NetBSD: getbsize.c,v 1.16 2005/11/29 03:11:59 christos 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 53 char * 54 getbsize(headerlenp, blocksizep) 55 int *headerlenp; 56 long *blocksizep; 57 { 58 static char header[20]; 59 long n, max, mul, blocksize; 60 char *ep, *p; 61 const char *form; 62 63 #define KB (1024L) 64 #define MB (1024L * 1024L) 65 #define GB (1024L * 1024L * 1024L) 66 #define MAXB GB /* No tera, peta, nor exa. */ 67 form = ""; 68 if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') { 69 if ((n = strtol(p, &ep, 10)) < 0) 70 goto underflow; 71 if (n == 0) 72 n = 1; 73 if (*ep && ep[1]) 74 goto fmterr; 75 switch (*ep) { 76 case 'G': case 'g': 77 form = "G"; 78 max = MAXB / GB; 79 mul = GB; 80 break; 81 case 'K': case 'k': 82 form = "K"; 83 max = MAXB / KB; 84 mul = KB; 85 break; 86 case 'M': case 'm': 87 form = "M"; 88 max = MAXB / MB; 89 mul = MB; 90 break; 91 case '\0': 92 max = MAXB; 93 mul = 1; 94 break; 95 default: 96 fmterr: warnx("%s: unknown blocksize", p); 97 n = 512; 98 mul = 1; 99 max = 0; 100 break; 101 } 102 if (n > max) { 103 warnx("maximum blocksize is %ldG", MAXB / GB); 104 n = max; 105 } 106 if ((blocksize = n * mul) < 512) { 107 underflow: warnx("%s: minimum blocksize is 512", p); 108 form = ""; 109 blocksize = n = 512; 110 } 111 } else 112 blocksize = n = 512; 113 114 if (headerlenp) 115 *headerlenp = 116 snprintf(header, sizeof(header), "%ld%s-blocks", n, form); 117 if (blocksizep) 118 *blocksizep = blocksize; 119 return (header); 120 } 121