GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/gen/devname.c Lines: 0 28 0.0 %
Date: 2017-11-13 Branches: 0 24 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: devname.c,v 1.13 2016/07/06 04:35:12 guenther Exp $ */
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/*
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 * Copyright (c) 1989, 1993
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <db.h>
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#include <dirent.h>
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#include <fcntl.h>
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#include <limits.h>
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#include <paths.h>
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#include <stdbool.h>
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#include <string.h>
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#include <stdlib.h>
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static char *
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devname_nodb(dev_t dev, mode_t type)
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{
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	static char buf[NAME_MAX + 1];
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	char *name = NULL;
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	struct dirent *dp;
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	struct stat sb;
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	DIR *dirp;
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	if ((dirp = opendir(_PATH_DEV)) == NULL)
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		return (NULL);
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	while ((dp = readdir(dirp)) != NULL) {
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		if (dp->d_type != DT_UNKNOWN && DTTOIF(dp->d_type) != type)
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			continue;
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		if (fstatat(dirfd(dirp), dp->d_name, &sb, AT_SYMLINK_NOFOLLOW)
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		    || sb.st_rdev != dev || (sb.st_mode & S_IFMT) != type)
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			continue;
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		strlcpy(buf, dp->d_name, sizeof(buf));
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		name = buf;
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		break;
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	}
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	closedir(dirp);
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	return (name);
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}
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/*
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 * Keys in dev.db are a mode_t followed by a dev_t.  The former is the
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 * type of the file (mode & S_IFMT), the latter is the st_rdev field.
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 * Note that the structure may contain padding.
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 */
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char *
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devname(dev_t dev, mode_t type)
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{
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	static DB *db;
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	static bool failure;
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	struct {
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		mode_t type;
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		dev_t dev;
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	} bkey;
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	DBT data, key;
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	char *name = NULL;
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	if (!db && !failure) {
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		if (!(db = dbopen(_PATH_DEVDB, O_RDONLY, 0, DB_HASH, NULL)))
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			failure = true;
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	}
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	if (!failure) {
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		/* Be sure to clear any padding that may be found in bkey.  */
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		memset(&bkey, 0, sizeof(bkey));
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		bkey.dev = dev;
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		bkey.type = type;
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		key.data = &bkey;
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		key.size = sizeof(bkey);
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		if ((db->get)(db, &key, &data, 0) == 0)
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			name = data.data;
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	} else {
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		name = devname_nodb(dev, type);
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	}
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	return (name ? name : "??");
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}
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DEF_WEAK(devname);