diff options
Diffstat (limited to 'source3')
| -rw-r--r-- | source3/Makefile.in | 3 | ||||
| -rw-r--r-- | source3/include/dbwrap.h | 8 | ||||
| -rw-r--r-- | source3/lib/dbwrap_tdb2.c | 1265 |
3 files changed, 1275 insertions, 1 deletions
diff --git a/source3/Makefile.in b/source3/Makefile.in index 1c760d8986..08883d8da4 100644 --- a/source3/Makefile.in +++ b/source3/Makefile.in @@ -247,7 +247,8 @@ LIBTDB_OBJ0 = @TDB_OBJS@ LIBTDB_OBJ = $(LIBTDB_OBJ0) $(LIBREPLACE_OBJ) TDB_OBJ = lib/util_tdb.o \ - lib/dbwrap.o lib/dbwrap_tdb.o lib/dbwrap_ctdb.o \ + lib/dbwrap.o lib/dbwrap_tdb.o \ + lib/dbwrap_tdb2.o lib/dbwrap_ctdb.o \ lib/dbwrap_rbt.o @LIBTDB_STATIC@ SMBLDAP_OBJ = @SMBLDAP@ @SMBLDAPUTIL@ diff --git a/source3/include/dbwrap.h b/source3/include/dbwrap.h index fe84709a81..1f388165db 100644 --- a/source3/include/dbwrap.h +++ b/source3/include/dbwrap.h @@ -66,6 +66,14 @@ struct db_context *db_open_tdb(TALLOC_CTX *mem_ctx, int hash_size, int tdb_flags, int open_flags, mode_t mode); +struct db_context *db_open_tdb2(TALLOC_CTX *mem_ctx, + const char *name, + int hash_size, int tdb_flags, + int open_flags, mode_t mode); + +struct messaging_context; +void db_tdb2_setup_messaging(struct messaging_context *msg_ctx, bool server); + #ifdef CLUSTER_SUPPORT struct db_context *db_open_ctdb(TALLOC_CTX *mem_ctx, const char *name, diff --git a/source3/lib/dbwrap_tdb2.c b/source3/lib/dbwrap_tdb2.c new file mode 100644 index 0000000000..cbcbe71d71 --- /dev/null +++ b/source3/lib/dbwrap_tdb2.c @@ -0,0 +1,1265 @@ +/* + Unix SMB/CIFS implementation. + + Database interface wrapper around tdb/ctdb + + Copyright (C) Volker Lendecke 2005-2007 + Copyright (C) Stefan Metzmacher 2008 + + 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/>. +*/ + +#include "includes.h" +#include "librpc/gen_ndr/ndr_messaging.h" + +struct db_tdb2_ctx { + struct db_context *db; + const char *name; + struct tdb_wrap *mtdb; + const char *mtdb_path; + bool master_transaction; + struct { + int hash_size; + int tdb_flags; + int open_flags; + mode_t mode; + } open; + struct tdb_wrap *ltdb; + const char *ltdb_path; + bool local_transaction; + int transaction; + bool out_of_sync; + uint32_t lseqnum; + uint32_t mseqnum; +#define DB_TDB2_MASTER_SEQNUM_KEYSTR "DB_TDB2_MASTER_SEQNUM_KEYSTR" + TDB_DATA mseqkey; + uint32_t max_buffer_size; + uint32_t current_buffer_size; + struct dbwrap_tdb2_changes changes; +}; + + +static NTSTATUS db_tdb2_store(struct db_record *rec, TDB_DATA data, int flag); +static NTSTATUS db_tdb2_delete(struct db_record *rec); + +static void db_tdb2_queue_change(struct db_tdb2_ctx *db_ctx, const TDB_DATA key); +static void db_tdb2_send_notify(struct db_tdb2_ctx *db_ctx); + +static struct db_context *db_open_tdb2_ex(TALLOC_CTX *mem_ctx, + const char *name, + int hash_size, int tdb_flags, + int open_flags, mode_t mode, + const struct dbwrap_tdb2_changes *chgs); + +static int db_tdb2_sync_from_master(struct db_tdb2_ctx *db_ctx, + const struct dbwrap_tdb2_changes *changes); + +static int db_tdb2_open_master(struct db_tdb2_ctx *db_ctx, bool transaction, + const struct dbwrap_tdb2_changes *changes); +static int db_tdb2_commit_local(struct db_tdb2_ctx *db_ctx, uint32_t mseqnum); +static int db_tdb2_close_master(struct db_tdb2_ctx *db_ctx); +static int db_tdb2_transaction_cancel(struct db_context *db); + +static void db_tdb2_receive_changes(struct messaging_context *msg, + void *private_data, + uint32_t msg_type, + struct server_id server_id, + DATA_BLOB *data); + +static struct messaging_context *global_tdb2_msg_ctx; +static bool global_tdb2_msg_ctx_initialized; + +void db_tdb2_setup_messaging(struct messaging_context *msg_ctx, bool server) +{ + global_tdb2_msg_ctx = msg_ctx; + + global_tdb2_msg_ctx_initialized = true; + + if (!server) { + return; + } + + if (!lp_parm_bool(-1, "dbwrap", "use_tdb2", false)) { + return; + } + + messaging_register(msg_ctx, NULL, MSG_DBWRAP_TDB2_CHANGES, + db_tdb2_receive_changes); +} + +static struct messaging_context *db_tdb2_get_global_messaging_context(void) +{ + struct messaging_context *msg_ctx; + + if (global_tdb2_msg_ctx_initialized) { + return global_tdb2_msg_ctx; + } + + msg_ctx = messaging_init(NULL, procid_self(), + event_context_init(NULL)); + + db_tdb2_setup_messaging(msg_ctx, false); + + return global_tdb2_msg_ctx; +} + +struct tdb_fetch_locked_state { + TALLOC_CTX *mem_ctx; + struct db_record *result; +}; + +static int db_tdb2_fetchlock_parse(TDB_DATA key, TDB_DATA data, + void *private_data) +{ + struct tdb_fetch_locked_state *state = + (struct tdb_fetch_locked_state *)private_data; + + state->result = (struct db_record *)talloc_size( + state->mem_ctx, + sizeof(struct db_record) + key.dsize + data.dsize); + + if (state->result == NULL) { + return 0; + } + + state->result->key.dsize = key.dsize; + state->result->key.dptr = ((uint8 *)state->result) + + sizeof(struct db_record); + memcpy(state->result->key.dptr, key.dptr, key.dsize); + + state->result->value.dsize = data.dsize; + + if (data.dsize > 0) { + state->result->value.dptr = state->result->key.dptr+key.dsize; + memcpy(state->result->value.dptr, data.dptr, data.dsize); + } + else { + state->result->value.dptr = NULL; + } + + return 0; +} + +static struct db_record *db_tdb2_fetch_locked(struct db_context *db, + TALLOC_CTX *mem_ctx, TDB_DATA key) +{ + struct db_tdb2_ctx *ctx = talloc_get_type_abort(db->private_data, + struct db_tdb2_ctx); + struct tdb_fetch_locked_state state; + + /* Do not accidently allocate/deallocate w/o need when debug level is lower than needed */ + if(DEBUGLEVEL >= 10) { + char *keystr = hex_encode(NULL, (unsigned char*)key.dptr, key.dsize); + DEBUG(10, (DEBUGLEVEL > 10 + ? "Locking key %s\n" : "Locking key %.20s\n", + keystr)); + TALLOC_FREE(keystr); + } + + /* + * we only support modifications within a + * started transaction. + */ + if (ctx->transaction == 0) { + DEBUG(0, ("db_tdb2_fetch_locked[%s]: no transaction started\n", + ctx->name)); + smb_panic("no transaction"); + return NULL; + } + + state.mem_ctx = mem_ctx; + state.result = NULL; + + tdb_parse_record(ctx->mtdb->tdb, key, db_tdb2_fetchlock_parse, &state); + + if (state.result == NULL) { + db_tdb2_fetchlock_parse(key, tdb_null, &state); + } + + if (state.result == NULL) { + return NULL; + } + + state.result->private_data = talloc_reference(state.result, ctx); + state.result->store = db_tdb2_store; + state.result->delete_rec = db_tdb2_delete; + + DEBUG(10, ("Allocated locked data 0x%p\n", state.result)); + + return state.result; +} + +struct tdb_fetch_state { + TALLOC_CTX *mem_ctx; + int result; + TDB_DATA data; +}; + +static int db_tdb2_fetch_parse(TDB_DATA key, TDB_DATA data, + void *private_data) +{ + struct tdb_fetch_state *state = + (struct tdb_fetch_state *)private_data; + + state->data.dptr = (uint8 *)talloc_memdup(state->mem_ctx, data.dptr, + data.dsize); + if (state->data.dptr == NULL) { + state->result = -1; + return 0; + } + + state->data.dsize = data.dsize; + return 0; +} + +static void db_tdb2_resync_before_read(struct db_tdb2_ctx *db_ctx, TDB_DATA *kbuf) +{ + if (db_ctx->mtdb) { + return; + } + + if (!db_ctx->out_of_sync) { + return; + } + + /* + * this function operates on the local copy, + * so hide the DB_TDB2_MASTER_SEQNUM_KEYSTR from the caller. + */ + if (kbuf && (db_ctx->mseqkey.dsize == kbuf->dsize) && + (memcmp(db_ctx->mseqkey.dptr, kbuf->dptr, kbuf->dsize) == 0)) { + return; + } + + DEBUG(0,("resync_before_read[%s/%s]\n", + db_ctx->mtdb_path, db_ctx->ltdb_path)); + + db_tdb2_open_master(db_ctx, false, NULL); + db_tdb2_close_master(db_ctx); +} + +static int db_tdb2_fetch(struct db_context *db, TALLOC_CTX *mem_ctx, + TDB_DATA key, TDB_DATA *pdata) +{ + struct db_tdb2_ctx *ctx = talloc_get_type_abort( + db->private_data, struct db_tdb2_ctx); + + struct tdb_fetch_state state; + + db_tdb2_resync_before_read(ctx, &key); + + if (ctx->out_of_sync) { + DEBUG(0,("out of sync[%s] failing fetch\n", + ctx->ltdb_path)); + errno = EIO; + return -1; + } + + state.mem_ctx = mem_ctx; + state.result = 0; + state.data = tdb_null; + + tdb_parse_record(ctx->ltdb->tdb, key, db_tdb2_fetch_parse, &state); + + if (state.result == -1) { + return -1; + } + + *pdata = state.data; + return 0; +} + +static NTSTATUS db_tdb2_store(struct db_record *rec, TDB_DATA data, int flag) +{ + struct db_tdb2_ctx *ctx = talloc_get_type_abort(rec->private_data, + struct db_tdb2_ctx); + int ret; + + /* + * This has a bug: We need to replace rec->value for correct + * operation, but right now brlock and locking don't use the value + * anymore after it was stored. + */ + + /* first store it to the master copy */ + ret = tdb_store(ctx->mtdb->tdb, rec->key, data, flag); + if (ret != 0) { + return NT_STATUS_UNSUCCESSFUL; + } + + /* then store it to the local copy */ + ret = tdb_store(ctx->ltdb->tdb, rec->key, data, flag); + if (ret != 0) { + /* try to restore the old value in the master copy */ + if (rec->value.dptr) { + tdb_store(ctx->mtdb->tdb, rec->key, + rec->value, TDB_REPLACE); + } else { + tdb_delete(ctx->mtdb->tdb, rec->key); + } + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + db_tdb2_queue_change(ctx, rec->key); + + return NT_STATUS_OK; +} + +static NTSTATUS db_tdb2_delete(struct db_record *rec) +{ + struct db_tdb2_ctx *ctx = talloc_get_type_abort(rec->private_data, + struct db_tdb2_ctx); + int ret; + + ret = tdb_delete(ctx->mtdb->tdb, rec->key); + if (ret != 0) { + if (tdb_error(ctx->mtdb->tdb) == TDB_ERR_NOEXIST) { + return NT_STATUS_NOT_FOUND; + } + + return NT_STATUS_UNSUCCESSFUL; + } + + ret = tdb_delete(ctx->ltdb->tdb, rec->key); + if (ret != 0) { + /* try to restore the value in the master copy */ + tdb_store(ctx->mtdb->tdb, rec->key, + rec->value, TDB_REPLACE); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + db_tdb2_queue_change(ctx, rec->key); + + return NT_STATUS_OK; +} + +struct db_tdb2_traverse_ctx { + struct db_tdb2_ctx *db_ctx; + int (*f)(struct db_record *rec, void *private_data); + void *private_data; +}; + +static int db_tdb2_traverse_func(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf, + void *private_data) +{ + struct db_tdb2_traverse_ctx *ctx = + (struct db_tdb2_traverse_ctx *)private_data; + struct db_record rec; + + /* this function operates on the master copy */ + + rec.key = kbuf; + rec.value = dbuf; + rec.store = db_tdb2_store; + rec.delete_rec = db_tdb2_delete; + rec.private_data = ctx->db_ctx; + + return ctx->f(&rec, ctx->private_data); +} + +static int db_tdb2_traverse(struct db_context *db, + int (*f)(struct db_record *rec, void *private_data), + void *private_data) +{ + struct db_tdb2_ctx *db_ctx = + talloc_get_type_abort(db->private_data, struct db_tdb2_ctx); + struct db_tdb2_traverse_ctx ctx; + + /* + * we only support modifications within a + * started transaction. + */ + if (db_ctx->transaction == 0) { + DEBUG(0, ("db_tdb2_traverse[%s]: no transaction started\n", + db_ctx->name)); + smb_panic("no transaction"); + return -1; + } + + /* here we traverse the master copy */ + ctx.db_ctx = db_ctx; + ctx.f = f; + ctx.private_data = private_data; + return tdb_traverse(db_ctx->mtdb->tdb, db_tdb2_traverse_func, &ctx); +} + +static NTSTATUS db_tdb2_store_deny(struct db_record *rec, TDB_DATA data, int flag) +{ + return NT_STATUS_MEDIA_WRITE_PROTECTED; +} + +static NTSTATUS db_tdb2_delete_deny(struct db_record *rec) +{ + return NT_STATUS_MEDIA_WRITE_PROTECTED; +} + +static int db_tdb2_traverse_read_func(TDB_CONTEXT *tdb, TDB_DATA kbuf, TDB_DATA dbuf, + void *private_data) +{ + struct db_tdb2_traverse_ctx *ctx = + (struct db_tdb2_traverse_ctx *)private_data; + struct db_record rec; + + /* + * this function operates on the local copy, + * so hide the DB_TDB2_MASTER_SEQNUM_KEYSTR from the caller. + */ + if ((ctx->db_ctx->mseqkey.dsize == kbuf.dsize) && + (memcmp(ctx->db_ctx->mseqkey.dptr, kbuf.dptr, kbuf.dsize) == 0)) { + return 0; + } + + rec.key = kbuf; + rec.value = dbuf; + rec.store = db_tdb2_store_deny; + rec.delete_rec = db_tdb2_delete_deny; + rec.private_data = ctx->db_ctx; + + return ctx->f(&rec, ctx->private_data); +} + +static int db_tdb2_traverse_read(struct db_context *db, + int (*f)(struct db_record *rec, void *private_data), + void *private_data) +{ + struct db_tdb2_ctx *db_ctx = + talloc_get_type_abort(db->private_data, struct db_tdb2_ctx); + struct db_tdb2_traverse_ctx ctx; + int ret; + + db_tdb2_resync_before_read(db_ctx, NULL); + + if (db_ctx->out_of_sync) { + DEBUG(0,("out of sync[%s] failing traverse_read\n", + db_ctx->ltdb_path)); + errno = EIO; + return -1; + } + + /* here we traverse the local copy */ + ctx.db_ctx = db_ctx; + ctx.f = f; + ctx.private_data = private_data; + ret = tdb_traverse_read(db_ctx->ltdb->tdb, db_tdb2_traverse_read_func, &ctx); + if (ret > 0) { + /* we have filtered one entry */ + ret--; + } + + return ret; +} + +static int db_tdb2_get_seqnum(struct db_context *db) + +{ + struct db_tdb2_ctx *db_ctx = + talloc_get_type_abort(db->private_data, struct db_tdb2_ctx); + uint32_t nlseq; + uint32_t nmseq; + bool ok; + + nlseq = tdb_get_seqnum(db_ctx->ltdb->tdb); + + if (nlseq == db_ctx->lseqnum) { + return db_ctx->mseqnum; + } + + ok = tdb_fetch_uint32_byblob(db_ctx->ltdb->tdb, + db_ctx->mseqkey, + &nmseq); + if (!ok) { + /* TODO: what should we do here? */ + return db_ctx->mseqnum; + } + + db_ctx->lseqnum = nlseq; + db_ctx->mseqnum = nmseq; + + return db_ctx->mseqnum; +} + +static int db_tdb2_transaction_start(struct db_context *db) +{ + struct db_tdb2_ctx *db_ctx = + talloc_get_type_abort(db->private_data, struct db_tdb2_ctx); + int ret; + + if (db_ctx->transaction) { + db_ctx->transaction++; + return 0; + } + + /* we need to open the master tdb in order to */ + ret = db_tdb2_open_master(db_ctx, true, NULL); + if (ret != 0) { + return ret; + } + + ret = tdb_transaction_start(db_ctx->ltdb->tdb); + if (ret != 0) { + db_tdb2_close_master(db_ctx); + return ret; + } + + db_ctx->local_transaction = true; + db_ctx->transaction = 1; + + return 0; +} + +static void db_tdb2_queue_change(struct db_tdb2_ctx *db_ctx, const TDB_DATA key) +{ + size_t size_needed = 4 + key.dsize; + size_t size_new = db_ctx->current_buffer_size + size_needed; + uint32_t i; + DATA_BLOB *keys; + + db_ctx->changes.num_changes++; + + if (db_ctx->changes.num_changes > 1 && + db_ctx->changes.keys == NULL) { + /* + * this means we already overflowed + */ + return; + } + + if (db_ctx->changes.num_changes == 1) { + db_ctx->changes.old_seqnum = db_ctx->mseqnum; + } + + for (i=0; i < db_ctx->changes.num_keys; i++) { + int ret; + + if (key.dsize != db_ctx->changes.keys[i].length) { + continue; + } + ret = memcmp(key.dptr, db_ctx->changes.keys[i].data, key.dsize); + if (ret != 0) { + continue; + } + + /* + * the key is already in the list + * so we're done + */ + return; + } + + if (db_ctx->max_buffer_size < size_new) { + goto overflow; + } + + keys = TALLOC_REALLOC_ARRAY(db_ctx, db_ctx->changes.keys, + DATA_BLOB, + db_ctx->changes.num_keys + 1); + if (!keys) { + goto overflow; + } + db_ctx->changes.keys = keys; + + keys[db_ctx->changes.num_keys].data = talloc_memdup(keys, + key.dptr, + key.dsize); + if (!keys[db_ctx->changes.num_keys].data) { + goto overflow; + } + keys[db_ctx->changes.num_keys].length = key.dsize; + db_ctx->changes.num_keys++; + db_ctx->current_buffer_size = size_new; + + return; + +overflow: + /* + * on overflow discard the buffer and let + * the others reload the whole tdb + */ + db_ctx->current_buffer_size = 0; + db_ctx->changes.num_keys = 0; + TALLOC_FREE(db_ctx->changes.keys); + return; +} + +static void db_tdb2_send_notify(struct db_tdb2_ctx *db_ctx) +{ + enum ndr_err_code ndr_err; + bool ok; + DATA_BLOB blob; + struct messaging_context *msg_ctx; + int num_msgs = 0; + struct server_id self = procid_self(); + + msg_ctx = db_tdb2_get_global_messaging_context(); + + db_ctx->changes.name = db_ctx->name; + + DEBUG(10,("%s[%s] size[%u/%u] changes[%u] keys[%u] seqnum[%u=>%u]\n", + __FUNCTION__, + db_ctx->changes.name, + db_ctx->current_buffer_size, + db_ctx->max_buffer_size, + db_ctx->changes.num_changes, + db_ctx->changes.num_keys, + db_ctx->changes.old_seqnum, + db_ctx->changes.new_seqnum)); + + if (db_ctx->changes.num_changes == 0) { + DEBUG(10,("db_tdb2_send_notify[%s]: no changes\n", + db_ctx->changes.name)); + goto done; + } + + if (!msg_ctx) { + DEBUG(1,("db_tdb2_send_notify[%s]: skipped (no msg ctx)\n", + db_ctx->changes.name)); + goto done; + } + + ndr_err = ndr_push_struct_blob( + &blob, talloc_tos(), &db_ctx->changes, + (ndr_push_flags_fn_t)ndr_push_dbwrap_tdb2_changes); + if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { + DEBUG(0,("db_tdb2_send_notify[%s]: failed to push changes: %s\n", + db_ctx->changes.name, + nt_errstr(ndr_map_error2ntstatus(ndr_err)))); + goto done; + } + + ok = message_send_all(msg_ctx, MSG_DBWRAP_TDB2_CHANGES, + blob.data, blob.length, &num_msgs); + if (!ok) { + DEBUG(0,("db_tdb2_send_notify[%s]: failed to send changes\n", + db_ctx->changes.name)); + goto done; + } + + DEBUG(10,("db_tdb2_send_notify[%s]: pid %s send %u messages\n", + db_ctx->name, procid_str_static(&self), num_msgs)); + +done: + TALLOC_FREE(db_ctx->changes.keys); + ZERO_STRUCT(db_ctx->changes); + + return; +} + +static void db_tdb2_receive_changes(struct messaging_context *msg, + void *private_data, + uint32_t msg_type, + struct server_id server_id, + DATA_BLOB *data) +{ + enum ndr_err_code ndr_err; + struct dbwrap_tdb2_changes changes; + struct db_context *db; + struct server_id self; + + if (procid_is_me(&server_id)) { + DEBUG(0,("db_tdb2_receive_changes: ignore selfpacket\n")); + return; + } + + self = procid_self(); + + DEBUG(10,("db_tdb2_receive_changes: from %s to %s\n", + procid_str(debug_ctx(), &server_id), + procid_str(debug_ctx(), &self))); + + ndr_err = ndr_pull_struct_blob_all( + data, talloc_tos(), &changes, + (ndr_pull_flags_fn_t)ndr_pull_dbwrap_tdb2_changes); + if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { + DEBUG(0,("db_tdb2_receive_changes: failed to pull changes: %s\n", + nt_errstr(ndr_map_error2ntstatus(ndr_err)))); + goto done; + } + + if(DEBUGLEVEL >= 10) { + NDR_PRINT_DEBUG(dbwrap_tdb2_changes, &changes); + } + + /* open the db, this will sync it */ + db = db_open_tdb2_ex(talloc_tos(), changes.name, 0, + 0, O_RDWR, 0600, &changes); + TALLOC_FREE(db); +done: + return; +} + +static int db_tdb2_transaction_commit(struct db_context *db) +{ + struct db_tdb2_ctx *db_ctx = + talloc_get_type_abort(db->private_data, struct db_tdb2_ctx); + int ret; + uint32_t mseqnum; + + if (db_ctx->transaction == 0) { + return -1; + } else if (db_ctx->transaction > 1) { + db_ctx->transaction--; + return 0; + } + + mseqnum = tdb_get_seqnum(db_ctx->mtdb->tdb); + db_ctx->changes.new_seqnum = mseqnum; + + /* first commit to the master copy */ + ret = tdb_transaction_commit(db_ctx->mtdb->tdb); + db_ctx->master_transaction = false; + if (ret != 0) { + int saved_errno = errno; + db_tdb2_transaction_cancel(db); + errno = saved_errno; + return ret; + } + + /* + * Note: as we've already commited the changes to the master copy + * so we ignore errors in the following functions + */ + ret = db_tdb2_commit_local(db_ctx, mseqnum); + if (ret == 0) { + db_ctx->out_of_sync = false; + } else { + db_ctx->out_of_sync = true; + } + + db_ctx->transaction = 0; + + db_tdb2_close_master(db_ctx); + + db_tdb2_send_notify(db_ctx); + + return 0; +} + +static int db_tdb2_transaction_cancel(struct db_context *db) +{ + struct db_tdb2_ctx *db_ctx = + talloc_get_type_abort(db->private_data, struct db_tdb2_ctx); + int saved_errno; + int ret; + + if (db_ctx->transaction == 0) { + return -1; + } + if (db_ctx->transaction > 1) { + db_ctx->transaction--; + return 0; + } + + /* cancel the transaction and close the master copy */ + ret = db_tdb2_close_master(db_ctx); + saved_errno = errno; + + /* now cancel on the local copy and ignore any error */ + tdb_transaction_cancel(db_ctx->ltdb->tdb); + db_ctx->local_transaction = false; + + db_ctx->transaction = 0; + + errno = saved_errno; + return ret; +} + +static int db_tdb2_open_master(struct db_tdb2_ctx *db_ctx, bool transaction, + const struct dbwrap_tdb2_changes *changes) +{ + int ret; + + db_ctx->mtdb = tdb_wrap_open(db_ctx, + db_ctx->mtdb_path, + db_ctx->open.hash_size, + db_ctx->open.tdb_flags|TDB_NOMMAP|TDB_SEQNUM, + db_ctx->open.open_flags, + db_ctx->open.mode); + if (db_ctx->mtdb == NULL) { + DEBUG(0, ("Could not open master tdb[%s]: %s\n", + db_ctx->mtdb_path, + strerror(errno))); + return -1; + } + DEBUG(10,("open_master[%s]\n", db_ctx->mtdb_path)); + + if (!db_ctx->ltdb) { + struct stat st; + + if (fstat(tdb_fd(db_ctx->mtdb->tdb), &st) == 0) { + db_ctx->open.mode = st.st_mode; + } + + /* make sure the local one uses the same hash size as the master one */ + db_ctx->open.hash_size = tdb_hash_size(db_ctx->mtdb->tdb); + + db_ctx->ltdb = tdb_wrap_open(db_ctx, + db_ctx->ltdb_path, + db_ctx->open.hash_size, + db_ctx->open.tdb_flags|TDB_SEQNUM, + db_ctx->open.open_flags|O_CREAT, + db_ctx->open.mode); + if (db_ctx->ltdb == NULL) { + DEBUG(0, ("Could not open local tdb[%s]: %s\n", + db_ctx->ltdb_path, + strerror(errno))); + TALLOC_FREE(db_ctx->mtdb); + return -1; + } + DEBUG(10,("open_local[%s]\n", db_ctx->ltdb_path)); + } + + if (transaction) { + ret = tdb_transaction_start(db_ctx->mtdb->tdb); + if (ret != 0) { + DEBUG(0,("open failed to start transaction[%s]\n", + db_ctx->mtdb_path)); + db_tdb2_close_master(db_ctx); + return ret; + } + db_ctx->master_transaction = true; + } + + ret = db_tdb2_sync_from_master(db_ctx, changes); + if (ret != 0) { + DEBUG(0,("open failed to sync from master[%s]\n", + db_ctx->ltdb_path)); + db_tdb2_close_master(db_ctx); + return ret; + } + + return 0; +} + +static int db_tdb2_commit_local(struct db_tdb2_ctx *db_ctx, uint32_t mseqnum) +{ + bool ok; + int ret; + + /* first fetch the master seqnum */ + db_ctx->mseqnum = mseqnum; + + /* now we try to store the master seqnum in the local tdb */ + ok = tdb_store_uint32_byblob(db_ctx->ltdb->tdb, + db_ctx->mseqkey, + db_ctx->mseqnum); + if (!ok) { + tdb_transaction_cancel(db_ctx->ltdb->tdb); + db_ctx->local_transaction = false; + DEBUG(0,("local failed[%s] store mseq[%u]\n", + db_ctx->ltdb_path, db_ctx->mseqnum)); + return -1; + } + + /* now commit all changes to the local tdb */ + ret = tdb_transaction_commit(db_ctx->ltdb->tdb); + db_ctx->local_transaction = false; + if (ret != 0) { + DEBUG(0,("local failed[%s] commit mseq[%u]\n", + db_ctx->ltdb_path, db_ctx->mseqnum)); + return ret; + } + + /* + * and update the cached local seqnum this is needed to + * let us cache the master seqnum. + */ + db_ctx->lseqnum = tdb_get_seqnum(db_ctx->ltdb->tdb); + DEBUG(10,("local updated[%s] mseq[%u]\n", + db_ctx->ltdb_path, db_ctx->mseqnum)); + + return 0; +} + +static int db_tdb2_close_master(struct db_tdb2_ctx *db_ctx) +{ + if (db_ctx->master_transaction) { + tdb_transaction_cancel(db_ctx->mtdb->tdb); + } + db_ctx->master_transaction = false; + /* now we can close the master handle */ + TALLOC_FREE(db_ctx->mtdb); + + DEBUG(10,("close_master[%s] ok\n", db_ctx->mtdb_path)); + return 0; +} + +static int db_tdb2_traverse_sync_all_func(TDB_CONTEXT *tdb, + TDB_DATA kbuf, TDB_DATA dbuf, + void *private_data) +{ + struct db_tdb2_traverse_ctx *ctx = + (struct db_tdb2_traverse_ctx *)private_data; + uint32_t *seqnum = (uint32_t *)ctx->private_data; + int ret; + + DEBUG(10,("sync_entry[%s]\n", ctx->db_ctx->mtdb_path)); + + /* Do not accidently allocate/deallocate w/o need when debug level is lower than needed */ + if(DEBUGLEVEL >= 10) { + char *keystr = hex_encode(NULL, (unsigned char*)kbuf.dptr, kbuf.dsize); + DEBUG(10, (DEBUGLEVEL > 10 + ? "Locking key %s\n" : "Locking key %.20s\n", + keystr)); + TALLOC_FREE(keystr); + } + + ret = tdb_store(ctx->db_ctx->ltdb->tdb, kbuf, dbuf, TDB_INSERT); + if (ret != 0) { + DEBUG(0,("sync_entry[%s] %d: %s\n", + ctx->db_ctx->ltdb_path, ret, + tdb_errorstr(ctx->db_ctx->ltdb->tdb))); + return ret; + } + + *seqnum = tdb_get_seqnum(ctx->db_ctx->mtdb->tdb); + + return 0; +} + +static int db_tdb2_sync_all(struct db_tdb2_ctx *db_ctx, uint32_t *seqnum) +{ + struct db_tdb2_traverse_ctx ctx; + int ret; + + ret = tdb_wipe_all(db_ctx->ltdb->tdb); + if (ret != 0) { + DEBUG(0,("tdb_wipe_all[%s] failed %d: %s\n", + db_ctx->ltdb_path, ret, + tdb_errorstr(db_ctx->ltdb->tdb))); + return ret; + } + + ctx.db_ctx = db_ctx; + ctx.f = NULL; + ctx.private_data = seqnum; + ret = tdb_traverse_read(db_ctx->mtdb->tdb, + db_tdb2_traverse_sync_all_func, + &ctx); + DEBUG(10,("db_tdb2_sync_all[%s] count[%d]\n", + db_ctx->mtdb_path, ret)); + if (ret < 0) { + return ret; + } + + return 0; +} + +static int db_tdb2_sync_changes(struct db_tdb2_ctx *db_ctx, + const struct dbwrap_tdb2_changes *changes, + uint32_t *seqnum) +{ + uint32_t cseqnum; + uint32_t mseqnum; + uint32_t i; + int ret; + bool need_full_sync = false; + + DEBUG(10,("db_tdb2_sync_changes[%s] changes[%u]\n", + changes->name, changes->num_changes)); + if(DEBUGLEVEL >= 10) { + NDR_PRINT_DEBUG(dbwrap_tdb2_changes, discard_const(changes)); + } + + /* for the master tdb for reading */ + ret = tdb_lockall_read(db_ctx->mtdb->tdb); + if (ret != 0) { + DEBUG(0,("tdb_lockall_read[%s] %d\n", db_ctx->mtdb_path, ret)); + return ret; + } + + /* first fetch seqnum we know about */ + cseqnum = db_tdb2_get_seqnum(db_ctx->db); + + /* then fetch the master seqnum */ + mseqnum = tdb_get_seqnum(db_ctx->mtdb->tdb); + + if (cseqnum == mseqnum) { + DEBUG(10,("db_tdb2_sync_changes[%s] uptodate[%u]\n", + db_ctx->mtdb_path, mseqnum)); + /* we hit a race before and now noticed we're uptodate */ + goto done; + } + + /* now see if the changes describe what we need */ + if (changes->old_seqnum != cseqnum) { + need_full_sync = true; + } + + if (changes->new_seqnum != mseqnum) { + need_full_sync = true; + } + + /* this was the overflow case */ + if (changes->num_keys == 0) { + need_full_sync = true; + } + + if (need_full_sync) { + tdb_unlockall_read(db_ctx->mtdb->tdb); + DEBUG(0,("fallback to full sync[%s] seq[%u=>%u] keys[%u]\n", + db_ctx->ltdb_path, cseqnum, mseqnum, + changes->num_keys)); + return db_tdb2_sync_all(db_ctx, &mseqnum); + } + + for (i=0; i < changes->num_keys; i++) { + const char *op = NULL; + bool del = false; + TDB_DATA key; + TDB_DATA val; + + key.dsize = changes->keys[i].length; + key.dptr = changes->keys[i].data; + + val = tdb_fetch(db_ctx->mtdb->tdb, key); + ret = tdb_error(db_ctx->mtdb->tdb); + if (ret == TDB_ERR_NOEXIST) { + del = true; + } else if (ret != 0) { + DEBUG(0,("sync_changes[%s] failure %d\n", + db_ctx->mtdb_path, ret)); + goto failed; + } + + if (del) { + op = "delete"; + ret = tdb_delete(db_ctx->ltdb->tdb, key); + DEBUG(10,("sync_changes[%s] delete key[%u] %d\n", + db_ctx->mtdb_path, i, ret)); + } else { + op = "store"; + ret = tdb_store(db_ctx->ltdb->tdb, key, + val, TDB_REPLACE); + DEBUG(10,("sync_changes[%s] store key[%u] %d\n", + db_ctx->mtdb_path, i, ret)); + } + SAFE_FREE(val.dptr); + if (ret != 0) { + DEBUG(0,("sync_changes[%s] %s key[%u] failed %d\n", + db_ctx->mtdb_path, op, i, ret)); + goto failed; + } + } + +done: + tdb_unlockall_read(db_ctx->mtdb->tdb); + + *seqnum = mseqnum; + return 0; +failed: + tdb_unlockall_read(db_ctx->mtdb->tdb); + return ret; +} + +static int db_tdb2_sync_from_master(struct db_tdb2_ctx *db_ctx, + const struct dbwrap_tdb2_changes *changes) +{ + int ret; + uint32_t cseqnum; + uint32_t mseqnum; + bool force = false; + + /* first fetch seqnum we know about */ + cseqnum = db_tdb2_get_seqnum(db_ctx->db); + + /* then fetch the master seqnum */ + mseqnum = tdb_get_seqnum(db_ctx->mtdb->tdb); + + if (db_ctx->lseqnum == 0) { + force = true; + } + + if (!force && cseqnum == mseqnum) { + DEBUG(10,("uptodate[%s] mseq[%u]\n", + db_ctx->ltdb_path, mseqnum)); + /* the local copy is uptodate, close the master db */ + return 0; + } + DEBUG(10,("not uptodate[%s] seq[%u=>%u]\n", + db_ctx->ltdb_path, cseqnum, mseqnum)); + + ret = tdb_transaction_start(db_ctx->ltdb->tdb); + if (ret != 0) { + DEBUG(0,("failed to start transaction[%s] %d: %s\n", + db_ctx->ltdb_path, ret, + tdb_errorstr(db_ctx->ltdb->tdb))); + db_ctx->out_of_sync = true; + return ret; + } + db_ctx->local_transaction = true; + + if (changes && !force) { + ret = db_tdb2_sync_changes(db_ctx, changes, &mseqnum); + if (ret != 0) { + db_ctx->out_of_sync = true; + tdb_transaction_cancel(db_ctx->ltdb->tdb); + db_ctx->local_transaction = false; + return ret; + } + } else { + ret = db_tdb2_sync_all(db_ctx, &mseqnum); + if (ret != 0) { + db_ctx->out_of_sync = true; + tdb_transaction_cancel(db_ctx->ltdb->tdb); + db_ctx->local_transaction = false; + return ret; + } + } + + ret = db_tdb2_commit_local(db_ctx, mseqnum); + if (ret != 0) { + db_ctx->out_of_sync = true; + return ret; + } + + db_ctx->out_of_sync = false; + + return 0; +} + +static int db_tdb2_ctx_destructor(struct db_tdb2_ctx *db_tdb2) +{ + db_tdb2_close_master(db_tdb2); + if (db_tdb2->local_transaction) { + tdb_transaction_cancel(db_tdb2->ltdb->tdb); + } + db_tdb2->local_transaction = false; + TALLOC_FREE(db_tdb2->ltdb); + return 0; +} + +static struct db_context *db_open_tdb2_ex(TALLOC_CTX *mem_ctx, + const char *name, + int hash_size, int tdb_flags, + int open_flags, mode_t mode, + const struct dbwrap_tdb2_changes *chgs) +{ + struct db_context *result = NULL; + struct db_tdb2_ctx *db_tdb2; + int ret; + const char *md; + const char *ld; + const char *bn; + + bn = strrchr_m(name, '/'); + if (bn) { + bn++; + DEBUG(3,("db_open_tdb2: use basename[%s] of abspath[%s]:\n", + bn, name)); + } else { + bn = name; + } + + md = lp_parm_const_string(-1, "dbwrap_tdb2", "master directory", NULL); + if (!md) { + DEBUG(0,("'dbwrap_tdb2:master directory' empty\n")); + goto fail; + } + + ld = lp_parm_const_string(-1, "dbwrap_tdb2", "local directory", NULL); + if (!ld) { + DEBUG(0,("'dbwrap_tdb2:local directory' empty\n")); + goto fail; + } + + result = TALLOC_ZERO_P(mem_ctx, struct db_context); + if (result == NULL) { + DEBUG(0, ("talloc failed\n")); + goto fail; + } + + result->private_data = db_tdb2 = TALLOC_ZERO_P(result, struct db_tdb2_ctx); + if (db_tdb2 == NULL) { + DEBUG(0, ("talloc failed\n")); + goto fail; + } + + db_tdb2->db = result; + + db_tdb2->open.hash_size = hash_size; + db_tdb2->open.tdb_flags = tdb_flags; + db_tdb2->open.open_flags= open_flags; + db_tdb2->open.mode = mode; + + db_tdb2->max_buffer_size = lp_parm_ulong(-1, "dbwrap_tdb2", + "notify buffer size", 512); + + db_tdb2->name = talloc_strdup(db_tdb2, bn); + if (db_tdb2->name == NULL) { + DEBUG(0, ("talloc_strdup failed\n")); + goto fail; + } + + db_tdb2->mtdb_path = talloc_asprintf(db_tdb2, "%s/%s", + md, bn); + if (db_tdb2->mtdb_path == NULL) { + DEBUG(0, ("talloc_asprintf failed\n")); + goto fail; + } + + db_tdb2->ltdb_path = talloc_asprintf(db_tdb2, "%s/%s.tdb2", + ld, bn); + if (db_tdb2->ltdb_path == NULL) { + DEBUG(0, ("talloc_asprintf failed\n")); + goto fail; + } + + db_tdb2->mseqkey = string_term_tdb_data(DB_TDB2_MASTER_SEQNUM_KEYSTR); + + /* + * this implicit opens the local one if as it's not yet open + * it syncs the local copy. + */ + ret = db_tdb2_open_master(db_tdb2, false, chgs); + if (ret != 0) { + goto fail; + } + + ret = db_tdb2_close_master(db_tdb2); + if (ret != 0) { + goto fail; + } + + DEBUG(10,("db_open_tdb2[%s] opened with mseq[%u]\n", + db_tdb2->name, db_tdb2->mseqnum)); + + result->fetch_locked = db_tdb2_fetch_locked; + result->fetch = db_tdb2_fetch; + result->traverse = db_tdb2_traverse; + result->traverse_read = db_tdb2_traverse_read; + result->get_seqnum = db_tdb2_get_seqnum; + result->persistent = ((tdb_flags & TDB_CLEAR_IF_FIRST) == 0); + result->transaction_start = db_tdb2_transaction_start; + result->transaction_commit = db_tdb2_transaction_commit; + result->transaction_cancel = db_tdb2_transaction_cancel; + + talloc_set_destructor(db_tdb2, db_tdb2_ctx_destructor); + + return result; + + fail: + if (result != NULL) { + TALLOC_FREE(result); + } + return NULL; +} + +struct db_context *db_open_tdb2(TALLOC_CTX *mem_ctx, + const char *name, + int hash_size, int tdb_flags, + int open_flags, mode_t mode) +{ + return db_open_tdb2_ex(mem_ctx, name, hash_size, + tdb_flags, open_flags, mode, NULL); +} |