mount_unionfs.c revision 1558
11558Srgrimes/* 21558Srgrimes * Copyright (c) 1992, 1993, 1994 31558Srgrimes * The Regents of the University of California. All rights reserved. 41558Srgrimes * 51558Srgrimes * This code is derived from software donated to Berkeley by 61558Srgrimes * Jan-Simon Pendry. 71558Srgrimes * 81558Srgrimes * Redistribution and use in source and binary forms, with or without 91558Srgrimes * modification, are permitted provided that the following conditions 101558Srgrimes * are met: 111558Srgrimes * 1. Redistributions of source code must retain the above copyright 121558Srgrimes * notice, this list of conditions and the following disclaimer. 131558Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141558Srgrimes * notice, this list of conditions and the following disclaimer in the 151558Srgrimes * documentation and/or other materials provided with the distribution. 161558Srgrimes * 3. All advertising materials mentioning features or use of this software 171558Srgrimes * must display the following acknowledgement: 181558Srgrimes * This product includes software developed by the University of 191558Srgrimes * California, Berkeley and its contributors. 201558Srgrimes * 4. Neither the name of the University nor the names of its contributors 211558Srgrimes * may be used to endorse or promote products derived from this software 221558Srgrimes * without specific prior written permission. 231558Srgrimes * 241558Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251558Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261558Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271558Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281558Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291558Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301558Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311558Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321558Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331558Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341558Srgrimes * SUCH DAMAGE. 351558Srgrimes */ 361558Srgrimes 371558Srgrimes#ifndef lint 381558Srgrimeschar copyright[] = 391558Srgrimes"@(#) Copyright (c) 1992, 1993, 1994\n\ 401558Srgrimes The Regents of the University of California. All rights reserved.\n"; 411558Srgrimes#endif /* not lint */ 421558Srgrimes 431558Srgrimes#ifndef lint 441558Srgrimesstatic char sccsid[] = "@(#)mount_union.c 8.5 (Berkeley) 3/27/94"; 451558Srgrimes#endif /* not lint */ 461558Srgrimes 471558Srgrimes#include <sys/param.h> 481558Srgrimes#include <sys/mount.h> 491558Srgrimes 501558Srgrimes#include <miscfs/union/union.h> 511558Srgrimes 521558Srgrimes#include <err.h> 531558Srgrimes#include <stdio.h> 541558Srgrimes#include <stdlib.h> 551558Srgrimes#include <string.h> 561558Srgrimes#include <unistd.h> 571558Srgrimes 581558Srgrimes#include "mntopts.h" 591558Srgrimes 601558Srgrimesstruct mntopt mopts[] = { 611558Srgrimes MOPT_STDOPTS, 621558Srgrimes { NULL } 631558Srgrimes}; 641558Srgrimes 651558Srgrimesint subdir __P((const char *, const char *)); 661558Srgrimesvoid usage __P((void)); 671558Srgrimes 681558Srgrimesint 691558Srgrimesmain(argc, argv) 701558Srgrimes int argc; 711558Srgrimes char *argv[]; 721558Srgrimes{ 731558Srgrimes struct union_args args; 741558Srgrimes int ch, mntflags; 751558Srgrimes char target[MAXPATHLEN]; 761558Srgrimes 771558Srgrimes mntflags = 0; 781558Srgrimes args.mntflags = UNMNT_ABOVE; 791558Srgrimes while ((ch = getopt(argc, argv, "bo:r")) != EOF) 801558Srgrimes switch (ch) { 811558Srgrimes case 'b': 821558Srgrimes args.mntflags &= ~UNMNT_OPMASK; 831558Srgrimes args.mntflags |= UNMNT_BELOW; 841558Srgrimes break; 851558Srgrimes case 'o': 861558Srgrimes getmntopts(optarg, mopts, &mntflags); 871558Srgrimes break; 881558Srgrimes case 'r': 891558Srgrimes args.mntflags &= ~UNMNT_OPMASK; 901558Srgrimes args.mntflags |= UNMNT_REPLACE; 911558Srgrimes break; 921558Srgrimes case '?': 931558Srgrimes default: 941558Srgrimes usage(); 951558Srgrimes /* NOTREACHED */ 961558Srgrimes } 971558Srgrimes argc -= optind; 981558Srgrimes argv += optind; 991558Srgrimes 1001558Srgrimes if (argc != 2) 1011558Srgrimes usage(); 1021558Srgrimes 1031558Srgrimes if (realpath(argv[0], target) == 0) 1041558Srgrimes err(1, "%s", target); 1051558Srgrimes 1061558Srgrimes if (subdir(target, argv[1]) || subdir(argv[1], target)) 1071558Srgrimes errx(1, "%s (%s) and %s are not distinct paths", 1081558Srgrimes argv[0], target, argv[1]); 1091558Srgrimes 1101558Srgrimes args.target = target; 1111558Srgrimes 1121558Srgrimes if (mount(MOUNT_UNION, argv[1], mntflags, &args)) 1131558Srgrimes err(1, NULL); 1141558Srgrimes exit(0); 1151558Srgrimes} 1161558Srgrimes 1171558Srgrimesint 1181558Srgrimessubdir(p, dir) 1191558Srgrimes const char *p; 1201558Srgrimes const char *dir; 1211558Srgrimes{ 1221558Srgrimes int l; 1231558Srgrimes 1241558Srgrimes l = strlen(dir); 1251558Srgrimes if (l <= 1) 1261558Srgrimes return (1); 1271558Srgrimes 1281558Srgrimes if ((strncmp(p, dir, l) == 0) && (p[l] == '/' || p[l] == '\0')) 1291558Srgrimes return (1); 1301558Srgrimes 1311558Srgrimes return (0); 1321558Srgrimes} 1331558Srgrimes 1341558Srgrimesvoid 1351558Srgrimesusage() 1361558Srgrimes{ 1371558Srgrimes (void)fprintf(stderr, 1381558Srgrimes "usage: mount_union [-br] [-o options] target_fs mount_point\n"); 1391558Srgrimes exit(1); 1401558Srgrimes} 141