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 * 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