/* Unix SMB/CIFS implementation. trivial database library Copyright (C) Jeremy Allison 2006 ** NOTE! The following LGPL license applies to the tdb ** library. This does NOT imply that all of Samba is released ** under the LGPL This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This library 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, see <http://www.gnu.org/licenses/>. */ #include "tdb_private.h" /* Check the freelist is good and contains no loops. Very memory intensive - only do this as a consistency checker. Heh heh - uses an in memory tdb as the storage for the "seen" record list. For some reason this strikes me as extremely clever as I don't have to write another tree data structure implementation :-). */ static int seen_insert(struct tdb_context *mem_tdb, tdb_off_t rec_ptr) { TDB_DATA key, data; memset(&data, '\0', sizeof(data)); key.dptr = (unsigned char *)&rec_ptr; key.dsize = sizeof(rec_ptr); return tdb_store(mem_tdb, key, data, TDB_INSERT); } int tdb_validate_freelist(struct tdb_context *tdb, int *pnum_entries) { struct tdb_context *mem_tdb = NULL; struct list_struct rec; tdb_off_t rec_ptr, last_ptr; int ret = -1; *pnum_entries = 0; mem_tdb = tdb_open("flval", tdb->header.hash_size, TDB_INTERNAL, O_RDWR, 0600); if (!mem_tdb) { return -1; } if (tdb_lock(tdb, -1, F_WRLCK) == -1) { tdb_close(mem_tdb); return 0; } last_ptr = FREELIST_TOP; /* Store the FREELIST_TOP record. */ if (seen_insert(mem_tdb, last_ptr) == -1) { ret = TDB_ERRCODE(TDB_ERR_CORRUPT, -1); goto fail; } /* read in the freelist top */ if (tdb_ofs_read(tdb, FREELIST_TOP, &rec_ptr) == -1) { goto fail; } while (rec_ptr) { /* If we can't store this record (we've seen it before) then the free list has a loop and must be corrupt. */ if (seen_insert(mem_tdb, rec_ptr)) { ret = TDB_ERRCODE(TDB_ERR_CORRUPT, -1); goto fail; } if (tdb_rec_free_read(tdb, rec_ptr, &rec) == -1) { goto fail; } /* move to the next record */ last_ptr = rec_ptr; rec_ptr = rec.next; *pnum_entries += 1; } ret = 0; fail: tdb_close(mem_tdb); tdb_unlock(tdb, -1, F_WRLCK); return ret; }