1 /* $OpenBSD: readlabel.c,v 1.10 2006/10/02 12:01:40 krw Exp $ */ 2 3 /* 4 * Copyright (c) 1996, Jason Downs. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, 19 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/types.h> 29 #include <stdio.h> 30 #include <err.h> 31 #include <errno.h> 32 #include <fcntl.h> 33 #include <paths.h> 34 #include <string.h> 35 #include <unistd.h> 36 #include <sys/dkio.h> 37 #define DKTYPENAMES 38 #include <sys/disklabel.h> 39 #include <sys/ioctl.h> 40 #include <sys/param.h> 41 #include <sys/stat.h> 42 43 #include "util.h" 44 45 /* 46 * Try to get a disklabel for the specified device, and return mount_xxx 47 * style filesystem type name for the specified partition. 48 */ 49 char * 50 readlabelfs(char *device, int verbose) 51 { 52 char rpath[MAXPATHLEN]; 53 struct disklabel dk; 54 char part, *type; 55 struct stat sbuf; 56 int fd; 57 58 /* Assuming device is of the form /dev/??p, build a raw partition. */ 59 if (stat(device, &sbuf) < 0) { 60 if (verbose) 61 warn("%s", device); 62 return (NULL); 63 } 64 switch (sbuf.st_mode & S_IFMT) { 65 case S_IFCHR: 66 /* Ok... already a raw device. Hmm. */ 67 strncpy(rpath, device, sizeof(rpath)); 68 rpath[sizeof(rpath) - 1] = '\0'; 69 70 /* Change partition name. */ 71 part = rpath[strlen(rpath) - 1]; 72 rpath[strlen(rpath) - 1] = 'a' + getrawpartition(); 73 break; 74 case S_IFBLK: 75 if (strlen(device) > sizeof(_PATH_DEV) - 1) { 76 snprintf(rpath, sizeof(rpath), "%sr%s", _PATH_DEV, 77 &device[sizeof(_PATH_DEV) - 1]); 78 /* Change partition name. */ 79 part = rpath[strlen(rpath) - 1]; 80 rpath[strlen(rpath) - 1] = 'a' + getrawpartition(); 81 break; 82 } 83 /* FALLTHROUGH */ 84 default: 85 if (verbose) 86 warnx("%s: not a device node", device); 87 return (NULL); 88 } 89 90 /* If rpath doesn't exist, change that partition back. */ 91 fd = open(rpath, O_RDONLY); 92 if (fd < 0) { 93 if (errno == ENOENT) { 94 rpath[strlen(rpath) - 1] = part; 95 96 fd = open(rpath, O_RDONLY); 97 if (fd < 0) { 98 if (verbose) 99 warn("%s", rpath); 100 return (NULL); 101 } 102 } else { 103 if (verbose) 104 warn("%s", rpath); 105 return (NULL); 106 } 107 } 108 if (ioctl(fd, DIOCGDINFO, &dk) < 0) { 109 if (verbose) 110 warn("%s: couldn't read disklabel", rpath); 111 close(fd); 112 return (NULL); 113 } 114 close(fd); 115 116 if (dk.d_partitions[part - 'a'].p_fstype >= FSMAXTYPES) { 117 if (verbose) 118 warnx("%s: bad filesystem type in label", rpath); 119 return (NULL); 120 } 121 122 type = fstypesnames[dk.d_partitions[part - 'a'].p_fstype]; 123 return ((type[0] == '\0') ? NULL : type); 124 } 125