persistent: add a client context to the persistent_stat and track the db_id

The db_id is tracked in the client context as an indication that a
transaction commit is in progress. This is cleared in the persistent_state
talloc destructor.

This is in order to properly treat running trans3_commits if the client
disconnects.

diff --git a/server/ctdb_persistent.c b/server/ctdb_persistent.c
index c7a53ca066f56b029b25593edf6bdf8768ae1578..0627037ea9246ef2dbe70df3de243aa0355a9451 100644 (file)
--- a/server/ctdb_persistent.c
+++ b/server/ctdb_persistent.c
@@ -29,6 +29,7 @@
 struct ctdb_persistent_state {
        struct ctdb_context *ctdb;
        struct ctdb_db_context *ctdb_db; /* used by trans3_commit */
+       struct ctdb_client *client; /* used by trans3_commit */
        struct ctdb_req_control *c;
        const char *errormsg;
        uint32_t num_pending;
@@ -277,6 +278,10 @@ int32_t ctdb_control_trans2_commit(struct ctdb_context *ctdb,
 
 static int ctdb_persistent_state_destructor(struct ctdb_persistent_state *state)
 {
+       if (state->client != NULL) {
+               state->client->db_id = 0;
+       }
+
        if (state->ctdb_db != NULL) {
                state->ctdb_db->persistent_state = NULL;
        }
@@ -303,6 +308,21 @@ int32_t ctdb_control_trans3_commit(struct ctdb_context *ctdb,
                return -1;
        }
 
+       client = ctdb_reqid_find(ctdb, c->client_id, struct ctdb_client);
+       if (client == NULL) {
+               DEBUG(DEBUG_ERR,(__location__ " can not match persistent_store "
+                                "to a client. Returning error\n"));
+               return -1;
+       }
+
+       if (client->db_id != 0) {
+               DEBUG(DEBUG_ERR,(__location__ " ERROR: trans3_commit: "
+                                "client-db_id[0x%08x] != 0 "
+                                "(client_id[0x%08x]): trans3_commit active?\n",
+                                client->db_id, client->client_id));
+               return -1;
+       }
+
        ctdb_db = find_ctdb_db(ctdb, m->db_id);
        if (ctdb_db == NULL) {
                DEBUG(DEBUG_ERR,(__location__ " ctdb_control_trans3_commit: "
@@ -318,21 +338,18 @@ int32_t ctdb_control_trans3_commit(struct ctdb_context *ctdb,
                return -1;
        }
 
-       client = ctdb_reqid_find(ctdb, c->client_id, struct ctdb_client);
-       if (client == NULL) {
-               DEBUG(DEBUG_ERR,(__location__ " can not match persistent_store "
-                                "to a client. Returning error\n"));
-               return -1;
-       }
-
        ctdb_db->persistent_state = talloc_zero(ctdb_db,
                                                struct ctdb_persistent_state);
        CTDB_NO_MEMORY(ctdb, ctdb_db->persistent_state);
 
+       client->db_id = m->db_id;
+
        state = ctdb_db->persistent_state;
        state->ctdb = ctdb;
        state->ctdb_db = ctdb_db;
        state->c    = c;
+       state->client = client;
+
        talloc_set_destructor(state, ctdb_persistent_state_destructor);
 
        for (i = 0; i < ctdb->vnn_map->size; i++) {