Setup delta-mmr using an overlay

diff --git a/servers/slapd/syncrepl.c b/servers/slapd/syncrepl.c
index 29efd16cbe05ca7ff290c6931ffb4bff9950cf63..d782f91b7169bd824da92ba90a8bd7cf76cf8ec6 100644 (file)
--- a/servers/slapd/syncrepl.c
+++ b/servers/slapd/syncrepl.c
@@ -144,6 +144,9 @@ static struct berval * slap_uuidstr_from_normalized(
 static int syncrepl_add_glue_ancestors(
        Operation* op, Entry *e );
 
+/* delta-mmr overlay handler */
+static int syncrepl_op_modify( Operation *op, SlapReply *rs );
+
 /* callback functions */
 static int dn_callback( Operation *, SlapReply * );
 static int nonpresent_callback( Operation *, SlapReply * );
@@ -171,12 +174,28 @@ syncrepl_state2str( int state )
        return "UNKNOWN";
 }
 
+static slap_overinst syncrepl_ov;
+
 static void
 init_syncrepl(syncinfo_t *si)
 {
        int i, j, k, l, n;
        char **attrs, **exattrs;
 
+       if ( !syncrepl_ov.on_bi.bi_type ) {
+               syncrepl_ov.on_bi.bi_type = "syncrepl";
+               syncrepl_ov.on_bi.bi_op_modify = syncrepl_op_modify;
+               overlay_register( &syncrepl_ov );
+       }
+
+       /* delta-MMR needs the overlay, nothing else does.
+        * This must happen before accesslog overlay is configured.
+        */
+       if ( si->si_syncdata &&
+               !overlay_is_inst( si->si_be, syncrepl_ov.on_bi.bi_type )) {
+               overlay_config( si->si_be, syncrepl_ov.on_bi.bi_type, -1, NULL, NULL );
+       }
+
        if ( !sync_descs[0] ) {
                sync_descs[0] = slap_schema.si_ad_objectClass;
                sync_descs[1] = slap_schema.si_ad_structuralObjectClass;
@@ -1745,6 +1764,32 @@ syncrepl_changelog_mods(
        return -1;      /* FIXME */
 }
 
+typedef struct OpExtraSync {
+       OpExtra oe;
+       syncinfo_t *oe_si;
+} OpExtraSync;
+
+static int
+syncrepl_op_modify( Operation *op, SlapReply *rs )
+{
+       OpExtra *oex;
+
+       LDAP_SLIST_FOREACH( oex, &op->o_extra, oe_next ) {
+               if ( oex->oe_key == (void *)syncrepl_message_to_op )
+                       break;
+       }
+       if ( !oex )
+               return SLAP_CB_CONTINUE;
+
+       /* Check if entryCSN in modlist is newer than entryCSN in entry.
+        * We do it here because the op has been serialized by accesslog
+        * by the time we get here. If the CSN is new enough, just do the
+        * mod. If not, we need to resolve conflicts.
+        */
+
+       return SLAP_CB_CONTINUE;
+}
+
 static int
 syncrepl_message_to_op(
        syncinfo_t      *si,
@@ -1904,9 +1949,19 @@ syncrepl_message_to_op(
                        if ( e == op->ora_e )
                                be_entry_release_w( op, op->ora_e );
                } else {
+                       OpExtraSync oes;
                        op->orm_modlist = modlist;
                        op->o_bd = si->si_wbe;
+                       /* delta-mmr needs additional checks in syncrepl_op_modify */
+                       if ( SLAP_MULTIMASTER( op->o_bd )) {
+                               oes.oe.oe_key = (void *)syncrepl_message_to_op;
+                               oes.oe_si = si;
+                               LDAP_SLIST_INSERT_HEAD( &op->o_extra, &oes.oe, oe_next );
+                       }
                        rc = op->o_bd->be_modify( op, &rs );
+                       if ( SLAP_MULTIMASTER( op->o_bd )) {
+                               LDAP_SLIST_REMOVE( &op->o_extra, &oes.oe, OpExtra, oe_next );
+                       }
                        modlist = op->orm_modlist;
                        Debug( rc ? LDAP_DEBUG_ANY : LDAP_DEBUG_SYNC,
                                "syncrepl_message_to_op: %s be_modify %s (%d)\n",