The main process (attendant) is no longer running the child_init()

The main proc must stay free of any db connections, so it can later fork and child_init() other procs (due auto_scaling).
For the modules which were keeping a DB conn open in main proc for later usage, during module destroy, the new approach is to open the conn, on the spot, in the destroy handler.

Related to #2003

(cherry picked from commit 3a8f6f1)

main.c

@@ -825,7 +825,7 @@ static int main_loop(void)
 
 	if (testing_framework) {
 		if (init_child(1) < 0) {
-			LM_ERR("error in init_child for PROC_MAIN\n");
+			LM_ERR("error in init_child for First Worker\n");
 			report_failure_status();
 			goto error;
 		}
@@ -834,12 +834,6 @@ static int main_loop(void)
 		shutdown_opensips(rc);
 	}
 
-	if (init_child(PROC_MAIN) < 0) {
-		LM_ERR("error in init_child for PROC_MAIN\n");
-		report_failure_status();
-		goto error;
-	}
-
 	report_conditional_status( (!no_daemon_mode), 0);
 
 	for(;;){

modules/alias_db/alias_db.c

@@ -254,9 +254,5 @@ static int mod_init(void)
  */
 static void destroy(void)
 {
-	if (db_handle) {
-		adbf.close(db_handle);
-		db_handle = 0;
-	}
 }
 

modules/auth_db/authdb_mod.c

@@ -231,10 +231,6 @@ static int mod_init(void)
 
 static void destroy(void)
 {
-	if (auth_db_handle) {
-		auth_dbf.close(auth_db_handle);
-		auth_db_handle = 0;
-	}
 	if (credentials) {
 		free_aaa_avp_list(credentials);
 		credentials = 0;

modules/avpops/avpops.c

@@ -310,8 +310,7 @@ static int avpops_init(void)
 
 static int avpops_child_init(int rank)
 {
-	/* skip main process and TCP manager process */
-	if (!need_db || rank==PROC_MAIN || rank==PROC_TCP_MAIN)
+	if (!need_db)
 		return 0;
 	/* init DB connection */
 	return avpops_db_init(&db_table, db_columns);

modules/b2b_entities/b2b_entities.c

@@ -351,10 +351,14 @@ static int child_init(int rank)
 /** Module destroy function */
 static void mod_destroy(void)
 {
-	if(b2be_db ) {
-		if(b2be_db_mode==WRITE_BACK)
+	if (b2be_dbf.init && b2be_db_mode==WRITE_BACK) {
+		b2be_db = b2be_dbf.init(&db_url);
+		if(!b2be_db) {
+			LM_ERR("connecting to database failed, unable to flush\n");
+		} else {
 			b2b_entities_dump(1);
-		b2be_dbf.close(b2be_db);
+			b2be_dbf.close(b2be_db);
+		}
 	}
 	destroy_b2b_htables();
 }

modules/b2b_logic/b2b_logic.c

@@ -750,11 +750,16 @@ static void mod_destroy(void)
 
 	b2b_scenario_t* scenario, *next;
 
-	if(b2bl_db)
-	{
-		if(b2bl_db_mode==WRITE_BACK)
+	if (b2bl_db_mode==WRITE_BACK && b2bl_dbf.init) {
+
+		b2bl_db = b2bl_dbf.init(&db_url);
+		if(!b2bl_db)
+		{
+			LM_ERR("connecting to database failed\n");
+		} else {
 			b2b_logic_dump(1);
-		b2bl_dbf.close(b2bl_db);
+			b2bl_dbf.close(b2bl_db);
+		}
 	}
 
 	scenario = extern_scenarios;

modules/b2b_sca/b2b_sca.c

@@ -346,7 +346,7 @@ static int mod_init(void)
 
 static int child_init(int rank)
 {
-	if (sca_db_mode==DB_MODE_REALTIME &&  (rank>PROC_MAIN || rank==PROC_MODULE)) {
+	if (sca_db_mode==DB_MODE_REALTIME &&  (rank>=1 || rank==PROC_MODULE)) {
 		if (connect_sca_db(&db_url)) {
 			LM_ERR("failed to connect to database (rank=%d)\n",rank);
 			return -1;
@@ -359,9 +359,6 @@ static int child_init(int rank)
 
 static void mod_destroy(void)
 {
-	//if (sca_db_mode != DB_MODE_NONE) {
-	//	sca_update_db();
-	//}
 	destroy_b2b_sca_handlers();
 	destroy_b2b_sca_htable();
 

modules/cachedb_couchbase/cachedb_couchbase.c

@@ -125,10 +125,6 @@ static int child_init(int rank)
 	struct cachedb_url *it;
 	cachedb_con *con;
 
-	if(rank == PROC_MAIN || rank == PROC_TCP_MAIN) {
-		return 0;
-	}
-
 	for (it = couchbase_script_urls;it;it=it->next) {
 		LM_DBG("iterating through couchbase conns - [%.*s]\n",it->url.len,it->url.s);
 		con = couchbase_init(&it->url);

modules/cachedb_memcached/cachedb_memcached.c

@@ -480,10 +480,6 @@ static int child_init(int rank)
 	struct cachedb_url *it;
 	cachedb_con *con;
 
-	if(rank == PROC_MAIN || rank == PROC_TCP_MAIN) {
-		return 0;
-	}
-
 	for (it = memcached_script_urls;it;it=it->next) {
 		con = memcached_init(&it->url);
 		if (con == NULL) {

modules/cachedb_mongodb/cachedb_mongodb.c

@@ -147,10 +147,6 @@ static int child_init(int rank)
 	struct cachedb_url *it;
 	cachedb_con *con;
 
-	if(rank == PROC_MAIN || rank == PROC_TCP_MAIN) {
-		return 0;
-	}
-
 	for (it = mongodb_script_urls;it;it=it->next) {
 		LM_DBG("iterating through conns - [%.*s]\n",it->url.len,it->url.s);
 		con = mongo_con_init(&it->url);

modules/cachedb_redis/cachedb_redis.c

@@ -122,10 +122,6 @@ static int child_init(int rank)
 	struct cachedb_url *it;
 	cachedb_con *con;
 
-	if(rank == PROC_MAIN || rank == PROC_TCP_MAIN) {
-		return 0;
-	}
-
 	for (it = redis_script_urls;it;it=it->next) {
 		LM_DBG("iterating through conns - [%.*s]\n",it->url.len,it->url.s);
 		con = redis_init(&it->url);

modules/call_center/call_center.c

@@ -308,7 +308,7 @@ static int mod_init(void)
 static int child_init( int rank )
 {
 	/* init DB connection */
-	if ( rank<PROC_MAIN)
+	if ( rank<1 )
 		return 0;
 	if ( cc_connect_db(&db_url)!=0 ) {
 		LM_CRIT("cannot initialize database connection\n");

modules/cgrates/cgrates.c

@@ -282,8 +282,12 @@ static int child_init(int rank)
 	struct cgr_engine *e;
 	struct cgr_conn *c;
 
-	/* connect to all servers */
-	/* go through each server and initialize a single connection */
+	/* external procs don't have a reactor, so they won't be able
+	 * to run any commands received by CGRateS, nor they will generate cmds */
+	if (rank == PROC_MODULE)
+		return 0;
+
+	/* go through each server and initialize a default connection */
 	list_for_each(l, &cgrates_engines) {
 		e = list_entry(l, struct cgr_engine, list);
 		/* start a connection for everybody */

modules/clusterer/clusterer_mod.c

@@ -1176,12 +1176,6 @@ int cmd_check_addr(struct sip_msg *msg, char *param_cluster, char *param_ip,
 
 static void destroy(void)
 {
-	if (db_hdl) {
-		/* close DB connection */
-		dr_dbf.close(db_hdl);
-		db_hdl = NULL;
-	}
-
 	/* destroy data */
 	if (cluster_list) {
 		if (*cluster_list)

modules/dialog/dialog.c

@@ -1022,12 +1022,9 @@ static void rpc_load_dlg_db(int sender, void *param)
 
 static int child_init(int rank)
 {
-	if (
-	(dlg_db_mode==DB_MODE_REALTIME && (rank>=PROC_MAIN||rank==PROC_MODULE)) ||
-	(dlg_db_mode==DB_MODE_SHUTDOWN && (rank==PROC_MAIN||rank==PROC_MODULE)) ||
-	(dlg_db_mode==DB_MODE_DELAYED  && (rank>=PROC_MAIN||rank==PROC_MODULE))
-	){
-		if ( dlg_connect_db(&db_url) ) {
+	if ( (dlg_db_mode==DB_MODE_REALTIME || dlg_db_mode==DB_MODE_DELAYED ) &&
+	(rank>=1 || rank==PROC_MODULE) ) {
+		if ( dlg_connect_db(&db_url)<0 ) {
 			LM_ERR("failed to connect to database (rank=%d)\n",rank);
 			return -1;
 		}
@@ -1050,8 +1047,12 @@ static void mod_destroy(void)
 	struct dlg_sharing_tag *tag, *tag_tmp;
 
 	if (dlg_db_mode != DB_MODE_NONE) {
-		dialog_update_db(0, 0/*do not do locking*/);
-		destroy_dlg_db();
+		if ( dlg_connect_db(&db_url)<0 ) {
+			LM_ERR("failed to connect to database\n");
+		} else {
+			dialog_update_db(0, 0/*do not do locking*/);
+			destroy_dlg_db();
+		}
 	}
 
 	if (shtags_list) {

modules/dispatcher/dispatcher.c

@@ -914,11 +914,10 @@ static int mod_init(void)
 #include "../../pt.h"
 static int ds_child_init(int rank)
 {
-	/* we need DB connection from the worker procs (for the flushing)
-	 * and from the main proc (for final flush on shutdown) */
-	if ( rank>=PROC_MAIN ) {
+	ds_partition_t *partition_it;
 
-		ds_partition_t *partition_it;
+	/* we need DB connection from the worker procs (for the flushing) */
+	if ( rank>=1 ) {
 
 		for (partition_it = partitions; partition_it;
 				partition_it = partition_it->next){
@@ -955,13 +954,22 @@ static int mi_child_init(void)
  */
 static void destroy(void)
 {
+	ds_partition_t *part_it = partitions, *aux;
+
 	LM_DBG("destroying module ...\n");
 
 	/* flush the state of the destinations */
-	if (ds_persistent_state)
-		ds_flusher_routine(0, NULL);
+	if (ds_persistent_state) {
+		/* open the DB conns*/
+		for (part_it = partitions; part_it; part_it = part_it->next) {
+			if (part_it->db_url.s)
+				if (ds_connect_db(part_it) != 0) {
+					LM_ERR("failed to do DB connect\n");
+				}
+		}
 
-	ds_partition_t *part_it = partitions, *aux;
+		ds_flusher_routine(0, NULL);
+	}
 
 	while (part_it) {
 		ds_destroy_data(part_it);

modules/dns_cache/dns_cache.c

@@ -144,8 +144,6 @@ static int child_init(int rank)
 static void destroy(void)
 {
 	LM_NOTICE("destroy module dns_cache ...\n");
-	if (cdbc)
-		cdbf.destroy(cdbc);
 }
 
 static int rdata_struct_len=sizeof(struct rdata)-sizeof(void *) -

modules/domain/domain_mod.c

@@ -286,7 +286,7 @@ static int mod_init(void)
 static int child_init(int rank)
 {
 	/* Check if database is needed by worker processes only */
-	if ( db_mode==0 && (rank>PROC_MAIN) ) {
+	if ( db_mode==0 && (rank>=1) ) {
 		if (domain_db_init(&db_url)<0) {
 			LM_ERR("Unable to connect to the database\n");
 			return -1;
@@ -304,10 +304,6 @@ static int mi_child_init(void)
 
 static void destroy(void)
 {
-	/* Destroy is called from the main process only,
-	 * there is no need to close database here because
-	 * it is closed in mod_init already
-	 */
 	if (hash_table) {
 		shm_free(hash_table);
 		hash_table = 0;

modules/domainpolicy/domainpolicy_mod.c

@@ -233,12 +233,9 @@ static int child_init(int rank)
 {
 	LM_DBG("initializing\n");
 
-	/* Check if database is needed by child */
-	if (rank!=PROC_MAIN && rank!=PROC_TCP_MAIN)  {
-		if (domainpolicy_db_init(&db_url)<0) {
-			LM_ERR("unable to connect to the database\n");
-			return -1;
-		}
+	if (domainpolicy_db_init(&db_url)<0) {
+		LM_ERR("unable to connect to the database\n");
+		return -1;
 	}
 	return 0;
 }

modules/drouting/drouting.c

@@ -1779,15 +1779,8 @@ static int dr_child_init(int rank)
 {
 	struct head_db *head_db_it = head_db_start;
 
-	/* We need DB connection from:
-	 *   - attendant - for shutdown, flushing state
-	 *   - timer - may trigger routes with dr group
-	 *   - workers - execute routes with dr group
-	 *   - module's proc - ??? */
-	if (rank==PROC_TCP_MAIN)
-		return 0;
-
 	LM_DBG("Child initialization on rank %d \n",rank);
+
 	while( head_db_it!=NULL ) {
 		db_load_head( head_db_it );
 		head_db_it = head_db_it->next;
@@ -1811,11 +1804,9 @@ static int dr_exit(void)
 	while( it!=NULL ) {
 		to_clean = it;
 		it = it->next;
-		if (dr_persistent_state && to_clean->db_con && *(to_clean->db_con))
+		if (dr_persistent_state && to_clean->db_con && *(to_clean->db_con)) {
 			dr_state_flusher(to_clean);
 
-		/* close DB connection */
-		if (to_clean->db_con && *(to_clean->db_con)) {
 			(to_clean->db_funcs).close(*(to_clean->db_con));
 			*(to_clean->db_con) = 0;
 			pkg_free(to_clean->db_con);

modules/emergency/emergency_methods.c

@@ -369,7 +369,7 @@ static int mod_init(void) {
 static int child_init(int rank) {
 	LM_DBG("Initializing child\n");
 
-	if (db_url.s && rank>PROC_MAIN) {
+	if (db_url.s && rank>=1) {
 		/* open a test connection */
 
 		if ((db_con = db_funcs.init(&db_url)) == 0) {
@@ -396,9 +396,6 @@ static int child_init(int rank) {
 static void mod_destroy(void) {
 	curl_global_cleanup();
 
-	if (db_con != NULL && db_funcs.close != 0)
-		db_funcs.close(db_con);
-
 	if(ref_lock){
 		lock_destroy_rw( ref_lock );
 		ref_lock = NULL;

modules/freeswitch_scripting/fss_mod.c

@@ -165,12 +165,13 @@ static int mod_init(void)
 
 	free_shm_str_dlist(&startup_fs_subs);
 
+	fss_db_close();
+
 	return 0;
 }
 
 static void mod_destroy(void)
 {
-	fss_db_close();
 }
 
 static int fixup_fs_esl(void **param, int param_no)

modules/group/group_mod.c

@@ -296,8 +296,6 @@ static int mod_init(void)
 
 static void destroy(void)
 {
-	if (!db_url.s)
-		group_db_close();
 }
 
 

modules/h350/h350_mod.c

@@ -138,12 +138,6 @@ struct module_exports exports = {
 
 static int child_init(int rank)
 {
-
-	/* don't do anything for non-worker process */
-	if (rank == PROC_MAIN || rank == PROC_TCP_MAIN) {
-		return 0;
-	}
-
 	h350_search_scope_int = ldap_api.ldap_str2scope(h350_search_scope.s);
 
 	/*