getbsize.c revision 256281
1210753Srpaulo/*- 2210753Srpaulo * Copyright (c) 1991, 1993 3210753Srpaulo * The Regents of the University of California. All rights reserved. 4210753Srpaulo * 5210753Srpaulo * Redistribution and use in source and binary forms, with or without 6210753Srpaulo * modification, are permitted provided that the following conditions 7210753Srpaulo * are met: 8210753Srpaulo * 1. Redistributions of source code must retain the above copyright 9210753Srpaulo * notice, this list of conditions and the following disclaimer. 10210753Srpaulo * 2. Redistributions in binary form must reproduce the above copyright 11210753Srpaulo * notice, this list of conditions and the following disclaimer in the 12210753Srpaulo * documentation and/or other materials provided with the distribution. 13210753Srpaulo * 4. Neither the name of the University nor the names of its contributors 14210753Srpaulo * may be used to endorse or promote products derived from this software 15210753Srpaulo * without specific prior written permission. 16210753Srpaulo * 17210753Srpaulo * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18210753Srpaulo * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19210753Srpaulo * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20210753Srpaulo * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21210753Srpaulo * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22210753Srpaulo * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23210753Srpaulo * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24210753Srpaulo * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25210753Srpaulo * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26210753Srpaulo * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27210753Srpaulo * SUCH DAMAGE. 28210753Srpaulo */ 29210753Srpaulo 30210753Srpaulo#if defined(LIBC_SCCS) && !defined(lint) 31210753Srpaulostatic char sccsid[] = "@(#)getbsize.c 8.1 (Berkeley) 6/4/93"; 32210753Srpaulo#endif /* LIBC_SCCS and not lint */ 33210753Srpaulo#include <sys/cdefs.h> 34210753Srpaulo__FBSDID("$FreeBSD: stable/10/lib/libc/gen/getbsize.c 181280 2008-08-04 06:53:13Z cperciva $"); 35210753Srpaulo 36210753Srpaulo#include <err.h> 37210753Srpaulo#include <stdio.h> 38210753Srpaulo#include <stdlib.h> 39210753Srpaulo#include <string.h> 40210753Srpaulo 41210753Srpaulochar * 42210753Srpaulogetbsize(headerlenp, blocksizep) 43210753Srpaulo int *headerlenp; 44210753Srpaulo long *blocksizep; 45210753Srpaulo{ 46210753Srpaulo static char header[20]; 47210753Srpaulo long n, max, mul, blocksize; 48210753Srpaulo char *ep, *p; 49210753Srpaulo const char *form; 50210753Srpaulo 51210753Srpaulo#define KB (1024L) 52210753Srpaulo#define MB (1024L * 1024L) 53210753Srpaulo#define GB (1024L * 1024L * 1024L) 54210753Srpaulo#define MAXB GB /* No tera, peta, nor exa. */ 55210753Srpaulo form = ""; 56210753Srpaulo if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') { 57210753Srpaulo if ((n = strtol(p, &ep, 10)) < 0) 58210753Srpaulo goto underflow; 59210753Srpaulo if (n == 0) 60210753Srpaulo n = 1; 61210753Srpaulo if (*ep && ep[1]) 62210753Srpaulo goto fmterr; 63210753Srpaulo switch (*ep) { 64210753Srpaulo case 'G': case 'g': 65210753Srpaulo form = "G"; 66210753Srpaulo max = MAXB / GB; 67210753Srpaulo mul = GB; 68210753Srpaulo break; 69210753Srpaulo case 'K': case 'k': 70210753Srpaulo form = "K"; 71210753Srpaulo max = MAXB / KB; 72210753Srpaulo mul = KB; 73210753Srpaulo break; 74210753Srpaulo case 'M': case 'm': 75210753Srpaulo form = "M"; 76210753Srpaulo max = MAXB / MB; 77210753Srpaulo mul = MB; 78210753Srpaulo break; 79 case '\0': 80 max = MAXB; 81 mul = 1; 82 break; 83 default: 84fmterr: warnx("%s: unknown blocksize", p); 85 n = 512; 86 max = MAXB; 87 mul = 1; 88 break; 89 } 90 if (n > max) { 91 warnx("maximum blocksize is %ldG", MAXB / GB); 92 n = max; 93 } 94 if ((blocksize = n * mul) < 512) { 95underflow: warnx("minimum blocksize is 512"); 96 form = ""; 97 blocksize = n = 512; 98 } 99 } else 100 blocksize = n = 512; 101 102 (void)snprintf(header, sizeof(header), "%ld%s-blocks", n, form); 103 *headerlenp = strlen(header); 104 *blocksizep = blocksize; 105 return (header); 106} 107