Runtime detection of BDB read-only transaction patch

diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index 7965cf8e6907132506ecaab15c7db48dbefbb50e..8e2ae440173196fde10830e5f8aa8d1b9ca03e10 100644 (file)
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -37,6 +37,14 @@ static void  bdb_lru_print(Cache *cache);
 
 static int bdb_txn_get( Operation *op, DB_ENV *env, DB_TXN **txn, int reset );
 
+/* 4.2.52 */
+#if DB_VERSION_FULL == 0x04020034
+#define        READ_TXN_FLAG   ReadFlag
+static int ReadFlag = DB_TXN_NOT_DURABLE;
+#else
+#define READ_TXN_FLAG  0
+#endif
+
 static EntryInfo *
 bdb_cache_entryinfo_new( Cache *cache )
 {
@@ -1258,7 +1266,17 @@ bdb_txn_get( Operation *op, DB_ENV *env, DB_TXN **txn, int reset )
        if ( ldap_pvt_thread_pool_getkey( ctx, ((char *)env)+1, &data, NULL ) ||
                data == NULL ) {
                for ( i=0, rc=1; rc != 0 && i<4; i++ ) {
-                       rc = TXN_BEGIN( env, NULL, txn, 0 );
+                       rc = TXN_BEGIN( env, NULL, txn, READ_TXN_FLAG );
+#if DB_VERSION_FULL == 0x04020034
+                       if ( rc == EINVAL && READ_TXN_FLAG ) {
+                               READ_TXN_FLAG = 0;
+                               Debug( LDAP_DEBUG_ANY,
+                                       "bdb_txn_get: BerkeleyDB library needs TXN patch!\n",
+                                       0, 0, 0 );
+                               i--;
+                               continue;
+                       }
+#endif
                        if (rc) ldap_pvt_thread_yield();
                }
                if ( rc != 0) {