1 /* $NetBSD: devname.c,v 1.6 1997/07/21 14:06:52 jtc Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)devname.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: devname.c,v 1.6 1997/07/21 14:06:52 jtc Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #include "namespace.h" 46 #include <sys/types.h> 47 48 #include <db.h> 49 #include <errno.h> 50 #include <fcntl.h> 51 #include <paths.h> 52 #include <stdio.h> 53 #include <string.h> 54 #include <stdlib.h> 55 #include <err.h> 56 57 #ifdef __weak_alias 58 __weak_alias(devname,_devname); 59 #endif 60 61 char * 62 devname(dev, type) 63 dev_t dev; 64 mode_t type; 65 { 66 struct { 67 mode_t type; 68 dev_t dev; 69 } bkey; 70 static DB *db; 71 static int failure; 72 DBT data, key; 73 74 if (!db && !failure && 75 !(db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL))) { 76 warn("warning: %s", _PATH_DEVDB); 77 failure = 1; 78 } 79 if (failure) 80 return ("??"); 81 82 /* 83 * Keys are a mode_t followed by a dev_t. The former is the type of 84 * the file (mode & S_IFMT), the latter is the st_rdev field. Be 85 * sure to clear any padding that may be found in bkey. 86 */ 87 memset(&bkey, 0, sizeof(bkey)); 88 bkey.dev = dev; 89 bkey.type = type; 90 key.data = &bkey; 91 key.size = sizeof(bkey); 92 return ((db->get)(db, &key, &data, 0) ? "??" : (char *)data.data); 93 } 94