NetBSD/usr.sbin/dev_mkdb/dev_mkdb.c

/*	$NetBSD: dev_mkdb.c,v 1.24 2007/12/15 19:44:55 perry Exp $	*/

/*-
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1990, 1993\n\
	The Regents of the University of California.  All rights reserved.\n");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "from: @(#)dev_mkdb.c	8.1 (Berkeley) 6/6/93";
#else
__RCSID("$NetBSD: dev_mkdb.c,v 1.24 2007/12/15 19:44:55 perry Exp $");
#endif
#endif /* not lint */

#include <sys/param.h>
#include <sys/stat.h>

#include <db.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <fts.h>
#include <kvm.h>
#include <nlist.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static void	usage(void) __unused;

HASHINFO openinfo = {
	4096,		/* bsize */
	128,		/* ffactor */
	1024,		/* nelem */
	2048 * 1024,	/* cachesize */
	NULL,		/* hash() */
	0		/* lorder */
};

int
main(int argc, char **argv)
{
	struct stat *st;
	struct {
		mode_t type;
		dev_t dev;
	} bkey;
	DB *db;
	DBT data, key;
	FTS *ftsp;
	FTSENT *p;
	int ch;
	char buf[MAXPATHLEN + 1];
	char dbtmp[MAXPATHLEN + 1];
	char dbname[MAXPATHLEN + 1];
	char *dbname_arg = NULL;
	char *pathv[2];
	char path_dev[MAXPATHLEN + 1] = _PATH_DEV;
	char cur_dir[MAXPATHLEN + 1];
	struct timeval tv;
	char *q;
	size_t dlen;

	setprogname(argv[0]);

	while ((ch = getopt(argc, argv, "o:")) != -1)
		switch (ch) {
		case 'o':
			dbname_arg = optarg;
			break;
		case '?':
		default:
			usage();
		}
	argc -= optind;
	argv += optind;

	if (argc == 1)
		if (strlcpy(path_dev, argv[0], sizeof(path_dev)) >=
		    sizeof(path_dev))
			errx(1, "device path too long");

	if (argc > 1)
		usage();

	if (getcwd(cur_dir, sizeof(cur_dir)) == NULL)
		err(1, "%s", cur_dir);

	if (chdir(path_dev) == -1)
		err(1, "%s", path_dev);

	pathv[0] = path_dev;
	pathv[1] = NULL;
	dlen = strlen(path_dev) - 1;
	ftsp = fts_open(pathv, FTS_PHYSICAL, NULL);
	if (ftsp == NULL)
		err(1, "fts_open: %s", path_dev);

	if (chdir(cur_dir) == -1)
		err(1, "%s", cur_dir);

	if (dbname_arg) {
		if (strlcpy(dbname, dbname_arg, sizeof(dbname)) >=
		    sizeof(dbname))
			errx(1, "dbname too long");
	} else {
		if (snprintf(dbname, sizeof(dbname), "%sdev.db",
		    _PATH_VARRUN) >= sizeof(dbname))
			errx(1, "dbname too long");
	}
	/* 
	 * We use rename() to produce the dev.db file from a temporary file,
	 * and rename() is not able to move files across filesystems. Hence we 
	 * need the temporary file to be in the same directory as dev.db.
	 *
	 * Additionally, we might be working in a world writable directory, 
	 * we must ensure that we are not opening an existing file, therefore
	 * the loop on dbopen. 
	 */
	(void)strlcpy(dbtmp, dbname, sizeof(dbtmp));
	q = dbtmp + strlen(dbtmp);
	do {
		(void)gettimeofday(&tv, NULL);
		(void)snprintf(q, sizeof(dbtmp) - (q - dbtmp), 
		    "%ld.tmp", tv.tv_usec);
		db = dbopen(dbtmp, O_CREAT|O_EXCL|O_EXLOCK|O_RDWR|O_TRUNC,
		    S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH, DB_HASH, &openinfo);
	} while (!db && (errno == EEXIST));
	if (db == NULL)
		err(1, "%s", dbtmp);

	/*
	 * Keys are a mode_t followed by a dev_t.  The former is the type of
	 * the file (mode & S_IFMT), the latter is the st_rdev field.  Note
	 * that the structure may contain padding, so we have to clear it
	 * out here.
	 */
	(void)memset(&bkey, 0, sizeof(bkey));
	key.data = &bkey;
	key.size = sizeof(bkey);
	data.data = (u_char *)(void *)buf;
	while ((p = fts_read(ftsp)) != NULL) {
		switch (p->fts_info) {
		case FTS_DEFAULT:
			st = p->fts_statp;
			break;
		default:
			continue;
		}

		/* Create the key. */
		if (S_ISCHR(st->st_mode))
			bkey.type = S_IFCHR;
		else if (S_ISBLK(st->st_mode))
			bkey.type = S_IFBLK;
		else
			continue;
		bkey.dev = st->st_rdev;

		/*
		 * Create the data; nul terminate the name so caller doesn't
		 * have to.  Skip path_dev and slash. Handle old versions
		 * of fts(3), that added multiple slashes, if the pathname
		 * ended with a slash.
		 */
		while (p->fts_path[dlen] == '/')
			dlen++;
		(void)strlcpy(buf, p->fts_path + dlen, sizeof(buf));
		data.size = p->fts_pathlen - dlen + 1;
		if ((*db->put)(db, &key, &data, 0))
			err(1, "dbput %s", dbtmp);
	}
	(void)(*db->close)(db);
	(void)fts_close(ftsp);

	if (chdir(cur_dir) == -1)
		err(1, "%s", cur_dir);
	if (rename(dbtmp, dbname) == -1)
		err(1, "rename %s to %s", dbtmp, dbname);
	return 0;
}

static void
usage(void)
{

	(void)fprintf(stderr, "Usage: %s [-o database] [directory]\n",
	    getprogname());
	exit(1);
}