1 /* $OpenBSD: readlabel.c,v 1.4 1997/11/18 19:57:29 millert 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 <util.h> 37 #include <sys/dkio.h> 38 #define DKTYPENAMES 39 #include <sys/disklabel.h> 40 #include <sys/ioctl.h> 41 #include <sys/param.h> 42 #include <sys/stat.h> 43 44 /* 45 * Try to get a disklabel for the specified device, and return mount_xxx 46 * style filesystem type name for the specified partition. 47 */ 48 49 char *readlabelfs(device, verbose) 50 char *device; 51 int verbose; 52 { 53 char rpath[MAXPATHLEN]; 54 char part, *type; 55 struct stat sbuf; 56 struct disklabel dk; 57 int fd; 58 59 /* Assuming device is of the form /dev/??p, build a raw partition. */ 60 if (stat(device, &sbuf) < 0) { 61 if (verbose) 62 warn("%s", device); 63 return(NULL); 64 } 65 switch(sbuf.st_mode & S_IFMT) { 66 case S_IFCHR: 67 /* Ok... already a raw device. Hmm. */ 68 strncpy(rpath, device, sizeof(rpath)); 69 rpath[sizeof(rpath) - 1] = '\0'; 70 71 /* Change partition name. */ 72 part = rpath[strlen(rpath) - 1]; 73 rpath[strlen(rpath) - 1] = 'a' + getrawpartition(); 74 break; 75 case S_IFBLK: 76 if (strlen(device) > strlen(_PATH_DEV)) { 77 snprintf(rpath, sizeof(rpath), "%sr%s", _PATH_DEV, 78 &device[strlen(_PATH_DEV)]); 79 80 /* Change partition name. */ 81 part = rpath[strlen(rpath) - 1]; 82 rpath[strlen(rpath) - 1] = 'a' + getrawpartition(); 83 break; 84 } 85 default: 86 if (verbose) 87 warnx("%s: not a device node", device); 88 return(NULL); 89 } 90 91 /* If rpath doesn't exist, change that partition back. */ 92 fd = open(rpath, O_RDONLY); 93 if (fd < 0) { 94 if (errno == ENOENT) { 95 rpath[strlen(rpath) - 1] = part; 96 97 fd = open(rpath, O_RDONLY); 98 if (fd < 0) { 99 if (verbose) 100 warn("%s", rpath); 101 return(NULL); 102 } 103 } else { 104 if (verbose) 105 warn("%s", rpath); 106 return(NULL); 107 } 108 } 109 if (ioctl(fd, DIOCGDINFO, &dk) < 0) { 110 if (verbose) 111 warn("%s: couldn't read disklabel", rpath); 112 close(fd); 113 return(NULL); 114 } 115 close(fd); 116 117 if (dk.d_partitions[part - 'a'].p_fstype > FSMAXTYPES) { 118 if (verbose) 119 warnx("%s: bad filesystem type in label", rpath); 120 return(NULL); 121 } 122 123 type = fstypesnames[dk.d_partitions[part - 'a'].p_fstype]; 124 return((type[0] == '\0') ? NULL : type); 125 } 126