1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: src/lib/libc/gen/devname.c,v 1.2.2.2 2001/07/31 20:10:19 tmm Exp $ 34 * $DragonFly: src/lib/libc/gen/devname.c,v 1.5 2005/01/31 22:29:15 dillon Exp $ 35 * 36 * @(#)devname.c 8.2 (Berkeley) 4/29/95 37 */ 38 39 #include <sys/types.h> 40 #include <sys/sysctl.h> 41 42 #include <db.h> 43 #include <err.h> 44 #include <fcntl.h> 45 #include <paths.h> 46 #include <stdio.h> 47 #include <string.h> 48 #include <sys/stat.h> 49 50 static char * 51 xdevname(dev_t dev, mode_t type) 52 { 53 struct { 54 mode_t type; 55 dev_t dev; 56 } bkey; 57 static DB *db; 58 static int failure; 59 DBT data, key; 60 61 if (!db && !failure && 62 !(db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL))) { 63 warn("warning: %s", _PATH_DEVDB); 64 failure = 1; 65 } 66 if (failure) 67 return (NULL); 68 69 /* 70 * Keys are a mode_t followed by a dev_t. The former is the type of 71 * the file (mode & S_IFMT), the latter is the st_rdev field. Be 72 * sure to clear any padding that may be found in bkey. 73 */ 74 memset(&bkey, 0, sizeof(bkey)); 75 bkey.dev = dev; 76 bkey.type = type; 77 key.data = &bkey; 78 key.size = sizeof(bkey); 79 return ((db->get)(db, &key, &data, 0) ? NULL : (char *)data.data); 80 } 81 82 char * 83 devname_r(dev_t dev, mode_t type, char *buf, size_t len) 84 { 85 int i; 86 size_t j; 87 char *r; 88 89 /* First check the DB file. */ 90 r = xdevname(dev, type); 91 if (r != NULL) { 92 strlcpy(buf, r, len); 93 return (buf); 94 } 95 96 #if 0 97 /* The kern.devname sysctl does not exist */ 98 /* Then ask the kernel. */ 99 if ((type & S_IFMT) == S_IFCHR) { 100 j = sizeof(buf); 101 i = sysctlbyname("kern.devname", buf, &j, &dev, sizeof (dev)); 102 if (i == 0) 103 return (buf); 104 } 105 #endif 106 107 /* Finally just format it */ 108 if (minor(dev) > 255) { 109 snprintf(buf, len, "#%c%d:0x%x", 110 (type & S_IFMT) == S_IFCHR ? 'C' : 'B', 111 major(dev), minor(dev)); 112 } else { 113 snprintf(buf, len, "#%c%d:%d", 114 (type & S_IFMT) == S_IFCHR ? 'C' : 'B', 115 major(dev), minor(dev)); 116 } 117 return (buf); 118 } 119 120 char * 121 devname(dev_t dev, mode_t type) 122 { 123 static char buf[30]; /* XXX: pick up from <sys/conf.h> */ 124 125 strncpy(buf, devname_r(dev, type, buf, sizeof(buf)), sizeof(buf)); 126 127 return (buf); 128 } 129