+++ /dev/null
-/*
- Unix SMB/CIFS implementation.
- low level tdb backup and restore utility
- Copyright (C) Andrew Tridgell 2002
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-/*
-
- This program is meant for backup/restore of tdb databases. Typical usage would be:
- tdbbackup *.tdb
- when Samba shuts down cleanly, which will make a backup of all the local databases
- to *.bak files. Then on Samba startup you would use:
- tdbbackup -v *.tdb
- and this will check the databases for corruption and if corruption is detected then
- the backup will be restored.
-
- You may also like to do a backup on a regular basis while Samba is
- running, perhaps using cron.
-
- The reason this program is needed is to cope with power failures
- while Samba is running. A power failure could lead to database
- corruption and Samba will then not start correctly.
-
- Note that many of the databases in Samba are transient and thus
- don't need to be backed up, so you can optimise the above a little
- by only running the backup on the critical databases.
-
- */
-
-#include "replace.h"
-#include "system/locale.h"
-#include "system/time.h"
-#include "system/filesys.h"
-#include "system/wait.h"
-#include "tdb.h"
-
-#ifdef HAVE_GETOPT_H
-#include <getopt.h>
-#endif
-
-static int failed;
-
-static char *add_suffix(const char *name, const char *suffix)
-{
- char *ret;
- int len = strlen(name) + strlen(suffix) + 1;
- ret = (char *)malloc(len);
- if (!ret) {
- fprintf(stderr,"Out of memory!\n");
- exit(1);
- }
- snprintf(ret, len, "%s%s", name, suffix);
- return ret;
-}
-
-static int copy_fn(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, void *state)
-{
- TDB_CONTEXT *tdb_new = (TDB_CONTEXT *)state;
-
- if (tdb_store(tdb_new, key, dbuf, TDB_INSERT) != 0) {
- fprintf(stderr,"Failed to insert into %s\n", tdb_name(tdb_new));
- failed = 1;
- return 1;
- }
- return 0;
-}
-
-
-static int test_fn(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, void *state)
-{
- return 0;
-}
-
-/*
- carefully backup a tdb, validating the contents and
- only doing the backup if its OK
- this function is also used for restore
-*/
-static int backup_tdb(const char *old_name, const char *new_name, int hash_size)
-{
- TDB_CONTEXT *tdb;
- TDB_CONTEXT *tdb_new;
- char *tmp_name;
- struct stat st;
- int count1, count2;
-
- tmp_name = add_suffix(new_name, ".tmp");
-
- /* stat the old tdb to find its permissions */
- if (stat(old_name, &st) != 0) {
- perror(old_name);
- free(tmp_name);
- return 1;
- }
-
- /* open the old tdb */
- tdb = tdb_open(old_name, 0, 0, O_RDWR, 0);
- if (!tdb) {
- printf("Failed to open %s\n", old_name);
- free(tmp_name);
- return 1;
- }
-
- /* create the new tdb */
- unlink(tmp_name);
- tdb_new = tdb_open(tmp_name,
- hash_size ? hash_size : tdb_hash_size(tdb),
- TDB_DEFAULT, O_RDWR|O_CREAT|O_EXCL,
- st.st_mode & 0777);
- if (!tdb_new) {
- perror(tmp_name);
- free(tmp_name);
- return 1;
- }
-
- /* lock the old tdb */
- if (tdb_lockall(tdb) != 0) {
- fprintf(stderr,"Failed to lock %s\n", old_name);
- tdb_close(tdb);
- tdb_close(tdb_new);
- unlink(tmp_name);
- free(tmp_name);
- return 1;
- }
-
- failed = 0;
-
- /* traverse and copy */
- count1 = tdb_traverse(tdb, copy_fn, (void *)tdb_new);
- if (count1 < 0 || failed) {
- fprintf(stderr,"failed to copy %s\n", old_name);
- tdb_close(tdb);
- tdb_close(tdb_new);
- unlink(tmp_name);
- free(tmp_name);
- return 1;
- }
-
- /* close the old tdb */
- tdb_close(tdb);
-
- /* close the new tdb and re-open read-only */
- tdb_close(tdb_new);
- tdb_new = tdb_open(tmp_name, 0, TDB_DEFAULT, O_RDONLY, 0);
- if (!tdb_new) {
- fprintf(stderr,"failed to reopen %s\n", tmp_name);
- unlink(tmp_name);
- perror(tmp_name);
- free(tmp_name);
- return 1;
- }
-
- /* traverse the new tdb to confirm */
- count2 = tdb_traverse(tdb_new, test_fn, NULL);
- if (count2 != count1) {
- fprintf(stderr,"failed to copy %s\n", old_name);
- tdb_close(tdb_new);
- unlink(tmp_name);
- free(tmp_name);
- return 1;
- }
-
- /* make sure the new tdb has reached stable storage */
- fsync(tdb_fd(tdb_new));
-
- /* close the new tdb and rename it to .bak */
- tdb_close(tdb_new);
- if (rename(tmp_name, new_name) != 0) {
- perror(new_name);
- free(tmp_name);
- return 1;
- }
-
- free(tmp_name);
-
- return 0;
-}
-
-/*
- verify a tdb and if it is corrupt then restore from *.bak
-*/
-static int verify_tdb(const char *fname, const char *bak_name)
-{
- TDB_CONTEXT *tdb;
- int count = -1;
-
- /* open the tdb */
- tdb = tdb_open(fname, 0, 0, O_RDONLY, 0);
-
- /* traverse the tdb, then close it */
- if (tdb) {
- count = tdb_traverse(tdb, test_fn, NULL);
- tdb_close(tdb);
- }
-
- /* count is < 0 means an error */
- if (count < 0) {
- printf("restoring %s\n", fname);
- return backup_tdb(bak_name, fname, 0);
- }
-
- printf("%s : %d records\n", fname, count);
-
- return 0;
-}
-
-/*
- see if one file is newer than another
-*/
-static int file_newer(const char *fname1, const char *fname2)
-{
- struct stat st1, st2;
- if (stat(fname1, &st1) != 0) {
- return 0;
- }
- if (stat(fname2, &st2) != 0) {
- return 1;
- }
- return (st1.st_mtime > st2.st_mtime);
-}
-
-static void usage(void)
-{
- printf("Usage: tdbbackup [options] <fname...>\n\n");
- printf(" -h this help message\n");
- printf(" -s suffix set the backup suffix\n");
- printf(" -v verify mode (restore if corrupt)\n");
- printf(" -n hashsize set the new hash size for the backup\n");
-}
-
-
- int main(int argc, char *argv[])
-{
- int i;
- int ret = 0;
- int c;
- int verify = 0;
- int hashsize = 0;
- const char *suffix = ".bak";
-
- while ((c = getopt(argc, argv, "vhs:n:")) != -1) {
- switch (c) {
- case 'h':
- usage();
- exit(0);
- case 'v':
- verify = 1;
- break;
- case 's':
- suffix = optarg;
- break;
- case 'n':
- hashsize = atoi(optarg);
- break;
- }
- }
-
- argc -= optind;
- argv += optind;
-
- if (argc < 1) {
- usage();
- exit(1);
- }
-
- for (i=0; i<argc; i++) {
- const char *fname = argv[i];
- char *bak_name;
-
- bak_name = add_suffix(fname, suffix);
-
- if (verify) {
- if (verify_tdb(fname, bak_name) != 0) {
- ret = 1;
- }
- } else {
- if (file_newer(fname, bak_name) &&
- backup_tdb(fname, bak_name, hashsize) != 0) {
- ret = 1;
- }
- }
-
- free(bak_name);
- }
-
- return ret;
-}
git.samba.org / samba.git / blobdiff