1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 <err.h> 33 #include <stdio.h> 34 #include <stdlib.h> 35 #include <string.h> 36 37 char * 38 getbsize(int *headerlenp, long *blocksizep) 39 { 40 static char header[20]; 41 long n, max, mul, blocksize; 42 char *ep, *p; 43 const char *form; 44 45 #define KB (1024L) 46 #define MB (1024L * 1024L) 47 #define GB (1024L * 1024L * 1024L) 48 #define MAXB GB /* No tera, peta, nor exa. */ 49 form = ""; 50 if ((p = getenv("BLOCKSIZE")) != NULL && *p != '\0') { 51 if ((n = strtol(p, &ep, 10)) < 0) 52 goto underflow; 53 if (n == 0) 54 n = 1; 55 if (*ep && ep[1]) 56 goto fmterr; 57 switch (*ep) { 58 case 'G': case 'g': 59 form = "G"; 60 max = MAXB / GB; 61 mul = GB; 62 break; 63 case 'K': case 'k': 64 form = "K"; 65 max = MAXB / KB; 66 mul = KB; 67 break; 68 case 'M': case 'm': 69 form = "M"; 70 max = MAXB / MB; 71 mul = MB; 72 break; 73 case '\0': 74 max = MAXB; 75 mul = 1; 76 break; 77 default: 78 fmterr: warnx("%s: unknown blocksize", p); 79 n = 512; 80 max = MAXB; 81 mul = 1; 82 break; 83 } 84 if (n > max) { 85 warnx("maximum blocksize is %ldG", MAXB / GB); 86 n = max; 87 } 88 if ((blocksize = n * mul) < 512) { 89 underflow: warnx("minimum blocksize is 512"); 90 form = ""; 91 blocksize = n = 512; 92 } 93 } else 94 blocksize = n = 512; 95 96 (void)snprintf(header, sizeof(header), "%ld%s-blocks", n, form); 97 *headerlenp = strlen(header); 98 *blocksizep = blocksize; 99 return (header); 100 } 101