1 /* 2 * Copyright (c) 1992, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software donated to Berkeley by 6 * Jan-Simon Pendry. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #ifndef lint 34 static const char copyright[] = 35 "@(#) Copyright (c) 1992, 1993, 1994\n\ 36 The Regents of the University of California. All rights reserved.\n"; 37 #endif /* not lint */ 38 39 #ifndef lint 40 #if 0 41 static char sccsid[] = "@(#)mount_union.c 8.5 (Berkeley) 3/27/94"; 42 #else 43 static const char rcsid[] = 44 "$FreeBSD$"; 45 #endif 46 #endif /* not lint */ 47 48 #include <sys/param.h> 49 #include <sys/mount.h> 50 #include <sys/uio.h> 51 52 #include <err.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <sysexits.h> 57 #include <unistd.h> 58 59 #include "mntopts.h" 60 61 static struct mntopt mopts[] = { 62 MOPT_STDOPTS, 63 MOPT_NULL 64 }; 65 66 static int subdir(const char *, const char *); 67 static void usage (void) __dead2; 68 69 int 70 main(argc, argv) 71 int argc; 72 char *argv[]; 73 { 74 struct iovec iov[8]; 75 int ch, mntflags; 76 char source[MAXPATHLEN]; 77 char target[MAXPATHLEN]; 78 int iovcnt; 79 80 iovcnt = 6; 81 mntflags = 0; 82 while ((ch = getopt(argc, argv, "bo:r")) != -1) 83 switch (ch) { 84 case 'b': 85 iov[6].iov_base = "below"; 86 iov[6].iov_len = strlen(iov[6].iov_base) + 1; 87 iov[7].iov_base = NULL; 88 iov[7].iov_len = 0; 89 iovcnt = 8; 90 break; 91 case 'o': 92 getmntopts(optarg, mopts, &mntflags, 0); 93 break; 94 case 'r': 95 iov[6].iov_base = "replace"; 96 iov[6].iov_len = strlen(iov[6].iov_base) + 1; 97 iov[7].iov_base = NULL; 98 iov[7].iov_len = 0; 99 iovcnt = 8; 100 break; 101 case '?': 102 default: 103 usage(); 104 /* NOTREACHED */ 105 } 106 argc -= optind; 107 argv += optind; 108 109 if (argc != 2) 110 usage(); 111 112 /* resolve both target and source with realpath(3) */ 113 (void)checkpath(argv[0], target); 114 (void)checkpath(argv[1], source); 115 116 if (subdir(target, source) || subdir(source, target)) 117 errx(EX_USAGE, "%s (%s) and %s (%s) are not distinct paths", 118 argv[0], target, argv[1], source); 119 120 iov[0].iov_base = "fstype"; 121 iov[0].iov_len = strlen(iov[0].iov_base) + 1; 122 iov[1].iov_base = "unionfs"; 123 iov[1].iov_len = strlen(iov[1].iov_base) + 1; 124 iov[2].iov_base = "fspath"; 125 iov[2].iov_len = strlen(iov[2].iov_base) + 1; 126 iov[3].iov_base = source; 127 iov[3].iov_len = strlen(source) + 1; 128 iov[4].iov_base = "target"; 129 iov[4].iov_len = strlen(iov[4].iov_base) + 1; 130 iov[5].iov_base = target; 131 iov[5].iov_len = strlen(target) + 1; 132 if (nmount(iov, iovcnt, mntflags)) 133 err(EX_OSERR, "%s", target); 134 exit(0); 135 } 136 137 int 138 subdir(p, dir) 139 const char *p; 140 const char *dir; 141 { 142 int l; 143 144 l = strlen(dir); 145 if (l <= 1) 146 return (1); 147 148 if ((strncmp(p, dir, l) == 0) && (p[l] == '/' || p[l] == '\0')) 149 return (1); 150 151 return (0); 152 } 153 154 void 155 usage() 156 { 157 (void)fprintf(stderr, 158 "usage: mount_unionfs [-br] [-o options] directory uniondir\n"); 159 exit(EX_USAGE); 160 } 161