[CBRD-25700] Modify the behavior to retain the session when automatic…

…ally restarting due to the CAS memory size limit

src/base/xserver_interface.h

@@ -262,7 +262,7 @@ extern int xlocator_upgrade_instances_domain (THREAD_ENTRY * thread_p, OID * cla
 
 extern int xsession_create_new (THREAD_ENTRY * thread_p, SESSION_ID * id);
 extern int xsession_check_session (THREAD_ENTRY * thread_p, const SESSION_ID id);
-extern int xsession_end_session (THREAD_ENTRY * thread, const SESSION_ID id);
+extern int xsession_end_session (THREAD_ENTRY * thread, const SESSION_ID id, bool is_keep_session);
 
 extern int xsession_set_row_count (THREAD_ENTRY * thread_p, int row_count);
 extern int xsession_get_row_count (THREAD_ENTRY * thread_p, int *row_count);

src/broker/cas.c

@@ -127,6 +127,7 @@ static void set_db_connection_info (void);
 static void clear_db_connection_info (void);
 static bool need_database_reconnect (void);
 
+extern bool db_Keep_session;
 extern bool ssl_client;
 extern int cas_init_ssl (int);
 extern void cas_ssl_close (int client_sock_fd);
@@ -1974,11 +1975,13 @@ process_request (SOCKET sock_fd, T_NET_BUF * net_buf, T_REQ_INFO * req_info)
 	      cas_log_msg = "RESET";
 	      cas_log_write_and_end (0, true, cas_log_msg);
 	      fn_ret = FN_KEEP_SESS;
+	      db_Keep_session = true;
 	    }
 	  if (as_info->con_status == CON_STATUS_CLOSE_AND_CONNECT)
 	    {
 	      cas_log_msg = "CHANGE CLIENT";
 	      fn_ret = FN_KEEP_SESS;
+	      db_Keep_session = true;
 	    }
 
 	  if (cas_log_msg == NULL)
@@ -2170,6 +2173,10 @@ process_request (SOCKET sock_fd, T_NET_BUF * net_buf, T_REQ_INFO * req_info)
   net_buf->client_version = req_info->client_version;
   set_hang_check_time ();
   fn_ret = (*server_fn) (sock_fd, argc, argv, net_buf, req_info);
+  if (fn_ret == FN_KEEP_SESS)
+    {
+      db_Keep_session = true;
+    }
   set_hang_check_time ();
 
 #if !defined(CAS_FOR_ORACLE) && !defined(CAS_FOR_MYSQL)
@@ -2242,6 +2249,7 @@ process_request (SOCKET sock_fd, T_NET_BUF * net_buf, T_REQ_INFO * req_info)
 	  else if (restart_is_needed ())
 	    {
 	      fn_ret = FN_KEEP_SESS;
+	      db_Keep_session = true;
 	    }
 	  if (shm_appl->sql_log2 != as_info->cur_sql_log2)
 	    {
@@ -2352,6 +2360,7 @@ process_request (SOCKET sock_fd, T_NET_BUF * net_buf, T_REQ_INFO * req_info)
     {
       cas_log_debug (ARG_FILE_LINE, "process_request: reset_flag && !CON_STATUS_IN_TRAN");
       fn_ret = FN_KEEP_SESS;
+      db_Keep_session = true;
       goto exit_on_end;
     }
 

src/communication/network_interface_cl.c

@@ -101,6 +101,8 @@ static int net_Deferred_end_queries_count = 0;
  */
 unsigned int db_on_server = 0;
 
+extern bool db_Keep_session;
+
 #if defined(CS_MODE)
 static char *pack_const_string (char *buffer, const char *cstring);
 static char *pack_string_with_null_padding (char *buffer, const char *stream, int len);
@@ -4742,14 +4744,15 @@ csession_end_session (SESSION_ID session_id)
   int req_error;
   OR_ALIGNED_BUF (OR_INT_SIZE) a_reply;
   char *reply;
-  OR_ALIGNED_BUF (OR_INT_SIZE) a_request;
+  OR_ALIGNED_BUF (OR_INT_SIZE * 2) a_request;
   char *request;
   char *ptr;
 
   reply = OR_ALIGNED_BUF_START (a_reply);
   request = OR_ALIGNED_BUF_START (a_request);
 
   ptr = or_pack_int (request, session_id);
+  ptr = or_pack_int (ptr, db_Keep_session);
 
   req_error =
     net_client_request (NET_SERVER_SES_END_SESSION, request, OR_ALIGNED_BUF_SIZE (a_request), reply,
@@ -4765,7 +4768,7 @@ csession_end_session (SESSION_ID session_id)
 
   THREAD_ENTRY *thread_p = enter_server ();
 
-  result = xsession_end_session (thread_p, session_id);
+  result = xsession_end_session (thread_p, session_id, db_Keep_session);
 
   exit_server (*thread_p);
 

src/communication/network_interface_sr.c

@@ -8986,14 +8986,16 @@ void
 ssession_end_session (THREAD_ENTRY * thread_p, unsigned int rid, char *request, int reqlen)
 {
   int err = NO_ERROR;
+  int is_keep_session;
   SESSION_ID id;
   OR_ALIGNED_BUF (OR_INT_SIZE) a_reply;
   char *reply = OR_ALIGNED_BUF_START (a_reply);
   char *ptr = NULL;
 
-  (void) or_unpack_int (request, (int *) &id);
+  ptr = or_unpack_int (request, (int *) &id);
+  ptr = or_unpack_int (ptr, (int *) &is_keep_session);
 
-  err = xsession_end_session (thread_p, id);
+  err = xsession_end_session (thread_p, id, (bool) is_keep_session);
 
   ptr = or_pack_int (reply, err);
   css_send_data_to_client (thread_p->conn_entry, rid, reply, OR_ALIGNED_BUF_SIZE (a_reply));

src/compat/db_admin.c

@@ -101,6 +101,8 @@ struct db_host_status_list
  The macros for testing this variable were moved to db.h so the query
  interface functions can use them as well. */
 
+extern bool db_Keep_session;
+
 char db_Database_name[DB_MAX_IDENTIFIER_LENGTH + 1];
 char db_Program_name[PATH_MAX];
 char db_Client_ip_addr[16] = { 0 };

src/compat/db_macro.c

@@ -90,6 +90,7 @@ int db_Connect_status = DB_CONNECTION_STATUS_CONNECTED;
 int db_Connect_status = DB_CONNECTION_STATUS_NOT_CONNECTED;
 #endif
 int db_Disable_modifications = 0;
+bool db_Keep_session = false;
 
 static int transfer_string (char *dst, int *xflen, int *outlen,
 			    const int dstlen, const char *src,

src/session/session.c

@@ -118,6 +118,7 @@ struct session_state
   pthread_mutex_t mutex;	/* state mutex */
   UINT64 del_id;		/* delete transaction ID (for lock free) */
 
+  bool is_keep_session;
   bool is_trigger_involved;
   bool is_last_insert_id_generated;
   bool auto_commit;
@@ -302,6 +303,7 @@ session_state_init (void *st)
   /* initialize fields */
   db_make_null (&session_p->cur_insert_id);
   db_make_null (&session_p->last_insert_id);
+  session_p->is_keep_session = false;
   session_p->is_trigger_involved = false;
   session_p->is_last_insert_id_generated = false;
   session_p->row_count = -1;
@@ -743,9 +745,10 @@ session_state_create (THREAD_ENTRY * thread_p, SESSION_ID * id)
  * session_state_destroy () - close a session state
  *   return	    : NO_ERROR or error code
  *   id(in) : the identifier for the session
+ *   is_keep_session(in) : whether to keep the session
  */
 int
-session_state_destroy (THREAD_ENTRY * thread_p, const SESSION_ID id)
+session_state_destroy (THREAD_ENTRY * thread_p, const SESSION_ID id, bool is_keep_session)
 {
   SESSION_STATE *session_p;
   int error = NO_ERROR, success = 0;
@@ -762,6 +765,13 @@ session_state_destroy (THREAD_ENTRY * thread_p, const SESSION_ID id)
       return ER_SES_SESSION_EXPIRED;
     }
 
+  if (is_keep_session == true)
+    {
+      session_p->is_keep_session = true;
+      pthread_mutex_unlock (&session_p->mutex);
+      return NO_ERROR;
+    }
+
 #if defined (SERVER_MODE)
   assert (session_p->ref_count > 0);
 
@@ -936,8 +946,17 @@ session_remove_expired_sessions (THREAD_ENTRY * thread_p)
 
 	      expired_sid_buffer[n_expired_sids++] = state->id;
 
-	      /* Destroy the session related resources like session parameters */
-	      (void) session_state_uninit (state);
+	      if (state->is_keep_session == true)
+		{
+		  /* keep session */
+		  pthread_mutex_unlock (&state->mutex);
+		  continue;
+		}
+	      else
+		{
+		  /* Destroy the session related resources like session parameters */
+		  (void) session_state_uninit (state);
+		}
 
 	      if (n_expired_sids == EXPIRED_SESSION_BUFFER_SIZE)
 		{

src/session/session.h

@@ -41,7 +41,7 @@ struct xasl_cache_ent;
 extern void session_states_init (THREAD_ENTRY * thread_p);
 extern void session_states_finalize (THREAD_ENTRY * thread_p);
 extern int session_state_create (THREAD_ENTRY * thread_p, SESSION_ID * id);
-extern int session_state_destroy (THREAD_ENTRY * thread_p, const SESSION_ID id);
+extern int session_state_destroy (THREAD_ENTRY * thread_p, const SESSION_ID id, bool is_keep_session);
 extern int session_check_session (THREAD_ENTRY * thread_p, const SESSION_ID id);
 extern int session_get_session_id (THREAD_ENTRY * thread_p, SESSION_ID * id);
 extern int session_get_last_insert_id (THREAD_ENTRY * thread_p, DB_VALUE * value, bool update_last_insert_id);

src/session/session_sr.c

@@ -62,11 +62,12 @@ xsession_check_session (THREAD_ENTRY * thread_p, const SESSION_ID id)
  *  return	    : error code
  *  id (in) : session id
  *  thread_p (in)
+ *  is_keep_session (in) : whether to keep the session
  */
 int
-xsession_end_session (THREAD_ENTRY * thread_p, const SESSION_ID id)
+xsession_end_session (THREAD_ENTRY * thread_p, const SESSION_ID id, bool is_keep_session)
 {
-  return session_state_destroy (thread_p, id);
+  return session_state_destroy (thread_p, id, is_keep_session);
 }
 
 /*