From: Gary Lockyer <gary@catalyst.net.nz>
Date: Thu, 22 Mar 2018 22:29:25 +0000 (+1300)
Subject: ldb_mdb: Remove implicit read lock and remove transaction counter
X-Git-Tag: ldb-1.4.0~97
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=65f6ce7a6e187ce45098b7fd88fdcda90b242837;p=thirdparty%2Fsamba.git

ldb_mdb: Remove implicit read lock and remove transaction counter

The way to know if we are in a transaction is if there is a non-NULL
transaction handle.

This allows the ldb_mdb_kv_ops_test test to be run.

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Signed-off-by: Gary Lockyer <gary@catalyst.net.nz>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>
---

diff --git a/lib/ldb/ldb_mdb/ldb_mdb.c b/lib/ldb/ldb_mdb/ldb_mdb.c
index 4eae7f45202..af552feb317 100644
--- a/lib/ldb/ldb_mdb/ldb_mdb.c
+++ b/lib/ldb/ldb_mdb/ldb_mdb.c
@@ -129,29 +129,21 @@ static struct lmdb_trans *lmdb_private_trans_head(struct lmdb_private *lmdb)
 	return ltx;
 }
 
+
 static MDB_txn *get_current_txn(struct lmdb_private *lmdb)
 {
 	MDB_txn *txn = NULL;
 
+	txn = lmdb_trans_get_tx(lmdb_private_trans_head(lmdb));
+	if (txn != NULL) {
+		return txn;
+	}
 	if (lmdb->read_txn != NULL) {
 		return lmdb->read_txn;
 	}
-
-	txn = lmdb_trans_get_tx(lmdb_private_trans_head(lmdb));
-	if (txn == NULL) {
-		int ret;
-		ret = mdb_txn_begin(lmdb->env, NULL, MDB_RDONLY, &txn);
-		if (ret != 0) {
-			lmdb->error = ret;
-			ldb_asprintf_errstring(lmdb->ldb,
-					       "%s failed: %s\n", __FUNCTION__,
-					       mdb_strerror(ret));
-			return NULL;
-		}
-		lmdb->read_txn = txn;
-	}
-
-	return txn;
+	lmdb->error = MDB_BAD_TXN;
+	ldb_set_errstring(lmdb->ldb, __location__":No active transaction\n");
+	return NULL;
 }
 
 static int lmdb_store(struct ltdb_private *ltdb,
@@ -197,10 +189,6 @@ static int lmdb_store(struct ltdb_private *ltdb,
 		MDB_val value;
 		lmdb->error = mdb_get(txn, dbi, &mdb_key, &value);
 		if (lmdb->error != MDB_SUCCESS) {
-			if (ltdb->read_lock_count == 0 && lmdb->read_txn != NULL) {
-				mdb_txn_commit(lmdb->read_txn);
-				lmdb->read_txn = NULL;
-			}
 			return ldb_mdb_error(lmdb->ldb, lmdb->error);
 		}
 		mdb_flags = 0;
@@ -304,11 +292,6 @@ done:
 		mdb_cursor_close(cursor);
 	}
 
-	if (ltdb->read_lock_count == 0 && lmdb->read_txn != NULL) {
-		mdb_txn_commit(lmdb->read_txn);
-		lmdb->read_txn = NULL;
-	}
-
 	if (lmdb->error != MDB_SUCCESS) {
 		return ldb_mdb_error(lmdb->ldb, lmdb->error);
 	}
@@ -414,10 +397,6 @@ static int lmdb_parse_record(struct ltdb_private *ltdb, struct ldb_val key,
 	if (lmdb->error != MDB_SUCCESS) {
 		/* TODO closing a handle should not even be necessary */
 		mdb_dbi_close(lmdb->env, dbi);
-		if (ltdb->read_lock_count == 0 && lmdb->read_txn != NULL) {
-			mdb_txn_commit(lmdb->read_txn);
-			lmdb->read_txn = NULL;
-		}
 		if (lmdb->error == MDB_NOTFOUND) {
 			return LDB_ERR_NO_SUCH_OBJECT;
 		}
@@ -429,11 +408,6 @@ static int lmdb_parse_record(struct ltdb_private *ltdb, struct ldb_val key,
 	/* TODO closing a handle should not even be necessary */
 	mdb_dbi_close(lmdb->env, dbi);
 
-	/* We created a read transaction, commit it */
-	if (ltdb->read_lock_count == 0 && lmdb->read_txn != NULL) {
-		mdb_txn_commit(lmdb->read_txn);
-		lmdb->read_txn = NULL;
-	}
 	return parser(key, data, ctx);
 }
 
@@ -517,7 +491,6 @@ static int lmdb_transaction_start(struct ltdb_private *ltdb)
 		return LDB_ERR_PROTOCOL_ERROR;
 	}
 
-
 	ltx_head = lmdb_private_trans_head(lmdb);
 
 	tx_parent = lmdb_trans_get_tx(ltx_head);
diff --git a/lib/ldb/wscript b/lib/ldb/wscript
index 80c817362f7..dfca1bc7b34 100644
--- a/lib/ldb/wscript
+++ b/lib/ldb/wscript
@@ -552,10 +552,12 @@ def test(ctx):
                  'ldb_tdb_kv_ops_test',
                  'ldb_tdb_test',
                  'ldb_mdb_mod_op_test',
-                 'ldb_lmdb_test']
+                 'ldb_lmdb_test',
                  # we don't want to run ldb_lmdb_size_test (which proves we can
                  # fit > 4G of data into the DB), it would fill up the disk on
                  # many of our test instances
+                 'ldb_mdb_kv_ops_test']
+
     for test_exe in test_exes:
             cmd = os.path.join(Utils.g_module.blddir, test_exe)
             cmocka_ret = cmocka_ret or samba_utils.RUN_COMMAND(cmd)