getbsize.c revision 105797
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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#if defined(LIBC_SCCS) && !defined(lint) 35static char sccsid[] = "@(#)getbsize.c 8.1 (Berkeley) 6/4/93"; 36#endif /* LIBC_SCCS and not lint */ 37#include <sys/cdefs.h> 38__FBSDID("$FreeBSD: head/lib/libc/gen/getbsize.c 105797 2002-10-23 14:18:07Z markm $"); 39 40#include <err.h> 41#include <stdio.h> 42#include <stdlib.h> 43#include <string.h> 44 45char * 46getbsize(headerlenp, blocksizep) 47 size_t *headerlenp; 48 long *blocksizep; 49{ 50 static char header[20]; 51 long n, max, mul, blocksize; 52 char *ep, *p; 53 const char *form; 54 55#define KB (1024L) 56#define MB (1024L * 1024L) 57#define GB (1024L * 1024L * 1024L) 58#define MAXB GB /* No tera, peta, nor exa. */ 59 form = ""; 60 if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') { 61 if ((n = strtol(p, &ep, 10)) < 0) 62 goto underflow; 63 if (n == 0) 64 n = 1; 65 if (*ep && ep[1]) 66 goto fmterr; 67 switch (*ep) { 68 case 'G': case 'g': 69 form = "G"; 70 max = MAXB / GB; 71 mul = GB; 72 break; 73 case 'K': case 'k': 74 form = "K"; 75 max = MAXB / KB; 76 mul = KB; 77 break; 78 case 'M': case 'm': 79 form = "M"; 80 max = MAXB / MB; 81 mul = MB; 82 break; 83 case '\0': 84 max = MAXB; 85 mul = 1; 86 break; 87 default: 88fmterr: warnx("%s: unknown blocksize", p); 89 n = 512; 90 mul = 1; 91 break; 92 } 93 if (n > max) { 94 warnx("maximum blocksize is %ldG", MAXB / GB); 95 n = max; 96 } 97 if ((blocksize = n * mul) < 512) { 98underflow: warnx("minimum blocksize is 512"); 99 form = ""; 100 blocksize = n = 512; 101 } 102 } else 103 blocksize = n = 512; 104 105 (void)snprintf(header, sizeof(header), "%ld%s-blocks", n, form); 106 *headerlenp = strlen(header); 107 *blocksizep = blocksize; 108 return (header); 109} 110