getbsize.c revision 181280
1164408Sceri/*- 2208291Suqs * Copyright (c) 1991, 1993 3164408Sceri * The Regents of the University of California. All rights reserved. 4164408Sceri * 5164408Sceri * Redistribution and use in source and binary forms, with or without 6164408Sceri * modification, are permitted provided that the following conditions 7164408Sceri * are met: 8164408Sceri * 1. Redistributions of source code must retain the above copyright 9164408Sceri * notice, this list of conditions and the following disclaimer. 10164408Sceri * 2. Redistributions in binary form must reproduce the above copyright 11164408Sceri * notice, this list of conditions and the following disclaimer in the 12164408Sceri * documentation and/or other materials provided with the distribution. 13164408Sceri * 4. Neither the name of the University nor the names of its contributors 14164408Sceri * may be used to endorse or promote products derived from this software 15164408Sceri * without specific prior written permission. 16164408Sceri * 17164408Sceri * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18164408Sceri * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19164408Sceri * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20164408Sceri * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21164408Sceri * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22164408Sceri * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23164408Sceri * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24164408Sceri * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25164408Sceri * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26164408Sceri * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27164408Sceri * SUCH DAMAGE. 28164408Sceri */ 29164408Sceri 30206622Suqs#if defined(LIBC_SCCS) && !defined(lint) 31164408Sceristatic char sccsid[] = "@(#)getbsize.c 8.1 (Berkeley) 6/4/93"; 32164408Sceri#endif /* LIBC_SCCS and not lint */ 33164408Sceri#include <sys/cdefs.h> 34164408Sceri__FBSDID("$FreeBSD: head/lib/libc/gen/getbsize.c 181280 2008-08-04 06:53:13Z cperciva $"); 35164408Sceri 36164408Sceri#include <err.h> 37164408Sceri#include <stdio.h> 38164408Sceri#include <stdlib.h> 39164408Sceri#include <string.h> 40164408Sceri 41164408Scerichar * 42164408Scerigetbsize(headerlenp, blocksizep) 43164408Sceri int *headerlenp; 44164408Sceri long *blocksizep; 45164408Sceri{ 46164408Sceri static char header[20]; 47164408Sceri long n, max, mul, blocksize; 48164408Sceri char *ep, *p; 49164408Sceri const char *form; 50164408Sceri 51164408Sceri#define KB (1024L) 52164408Sceri#define MB (1024L * 1024L) 53164408Sceri#define GB (1024L * 1024L * 1024L) 54164408Sceri#define MAXB GB /* No tera, peta, nor exa. */ 55164408Sceri form = ""; 56164408Sceri if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') { 57164408Sceri if ((n = strtol(p, &ep, 10)) < 0) 58164408Sceri goto underflow; 59164408Sceri if (n == 0) 60164408Sceri n = 1; 61164408Sceri if (*ep && ep[1]) 62164408Sceri goto fmterr; 63164408Sceri switch (*ep) { 64164408Sceri case 'G': case 'g': 65164408Sceri form = "G"; 66164408Sceri max = MAXB / GB; 67164408Sceri mul = GB; 68164408Sceri break; 69164408Sceri case 'K': case 'k': 70164408Sceri form = "K"; 71164408Sceri max = MAXB / KB; 72164408Sceri mul = KB; 73164408Sceri break; 74164408Sceri case 'M': case 'm': 75164408Sceri form = "M"; 76164408Sceri max = MAXB / MB; 77164408Sceri mul = MB; 78164408Sceri break; 79164408Sceri case '\0': 80164408Sceri max = MAXB; 81164408Sceri mul = 1; 82164408Sceri break; 83164408Sceri default: 84164408Scerifmterr: warnx("%s: unknown blocksize", p); 85164408Sceri n = 512; 86164408Sceri max = MAXB; 87164408Sceri mul = 1; 88164408Sceri break; 89164408Sceri } 90164408Sceri if (n > max) { 91164408Sceri warnx("maximum blocksize is %ldG", MAXB / GB); 92164408Sceri n = max; 93164408Sceri } 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