diff options
| author | Ronnie Sahlberg <ronniesahlberg@gmail.com> | 2009-05-25 17:04:42 +1000 |
|---|---|---|
| committer | Ronnie Sahlberg <ronniesahlberg@gmail.com> | 2009-05-25 17:04:42 +1000 |
| commit | 6feb7a1bf8f5f4a8a679f97d528e4148516e9a21 (patch) | |
| tree | 8cf791f7e024743e6bb731fe0f1fd0830e95858b | |
| parent | 96340bd1667c5ce5e932d954d67f2353f14b1afe (diff) | |
| download | samba-6feb7a1bf8f5f4a8a679f97d528e4148516e9a21.tar.gz samba-6feb7a1bf8f5f4a8a679f97d528e4148516e9a21.tar.xz samba-6feb7a1bf8f5f4a8a679f97d528e4148516e9a21.zip | |
New attempt at TDB transaction nesting allow/disallow.
Make the default be that transaction is not allowed and any attempt to create a nested transaction will fail with TDB_ERR_NESTING.
If an application can cope with transaction nesting and the implicit
semantics of tdb_transaction_commit(), it can enable transaction nesting
by using the TDB_ALLOW_NESTING flag.
(This used to be ctdb commit 3e49e41c21eb8c53084aa8cc7fd3557bdd8eb7b6)
| -rw-r--r-- | ctdb/lib/tdb/common/transaction.c | 11 | ||||
| -rw-r--r-- | ctdb/lib/tdb/include/tdb.h | 4 |
2 files changed, 14 insertions, 1 deletions
diff --git a/ctdb/lib/tdb/common/transaction.c b/ctdb/lib/tdb/common/transaction.c index 4e2127be64..98e8effcba 100644 --- a/ctdb/lib/tdb/common/transaction.c +++ b/ctdb/lib/tdb/common/transaction.c @@ -85,6 +85,13 @@ still available, but no transaction recovery area is used and no fsync/msync calls are made. + - if TDB_ALLOW_NESTING is passed to flags in tdb open, or added using + tdb_add_flags() transaction is enabled. + The default is that transaction nesting is not allowed and an attempt + to create a nested transaction will fail with TDB_ERR_NESTING. + + Beware. when transactions are nested a transaction successfully + completed with tdb_transaction_commit() can be silently unrolled later. */ @@ -409,6 +416,10 @@ int tdb_transaction_start(struct tdb_context *tdb) /* cope with nested tdb_transaction_start() calls */ if (tdb->transaction != NULL) { + if (!(tdb->flags & TDB_ALLOW_NESTING)) { + tdb->ecode = TDB_ERR_NESTING; + return -1; + } tdb->transaction->nesting++; TDB_LOG((tdb, TDB_DEBUG_TRACE, "tdb_transaction_start: nesting %d\n", tdb->transaction->nesting)); diff --git a/ctdb/lib/tdb/include/tdb.h b/ctdb/lib/tdb/include/tdb.h index 0008085de5..e678a7f277 100644 --- a/ctdb/lib/tdb/include/tdb.h +++ b/ctdb/lib/tdb/include/tdb.h @@ -47,13 +47,15 @@ extern "C" { #define TDB_NOSYNC 64 /* don't use synchronous transactions */ #define TDB_SEQNUM 128 /* maintain a sequence number */ #define TDB_VOLATILE 256 /* Activate the per-hashchain freelist, default 5 */ +#define TDB_ALLOW_NESTING 512 /* Allow transactions to nest */ #define TDB_ERRCODE(code, ret) ((tdb->ecode = (code)), ret) /* error codes */ enum TDB_ERROR {TDB_SUCCESS=0, TDB_ERR_CORRUPT, TDB_ERR_IO, TDB_ERR_LOCK, TDB_ERR_OOM, TDB_ERR_EXISTS, TDB_ERR_NOLOCK, TDB_ERR_LOCK_TIMEOUT, - TDB_ERR_NOEXIST, TDB_ERR_EINVAL, TDB_ERR_RDONLY}; + TDB_ERR_NOEXIST, TDB_ERR_EINVAL, TDB_ERR_RDONLY, + TDB_ERR_NESTING}; /* debugging uses one of the following levels */ enum tdb_debug_level {TDB_DEBUG_FATAL = 0, TDB_DEBUG_ERROR, |