Fix to bug #662, http://bugs.mariadb.com/show_bug.cgi?id=662

dbusers.c: Added function for setting read, write and connection timeout values. Set default timeouts for getUsers. Defaults are listed in service.c
gateway.c:shutdown_server is called whenever MaxScale is to be shut down. Added call for service_shutdown to shutdown_server.
service.c:service_alloc: replaced malloc with calloc and removed unnecessary zero/NULL initialization statements as a consequence.
	serviceStart: Exit serviceStartPort loop if shutdown flag is set for the service.
	serviceStartAll: Exit serviceStart loop if shutdown flag is set for the service.
service.c: Added service_shutdown which sets shutdown flag for each service found in allServices list.
service.h: Added prototype for service_shutdown

server/core/dbusers.c

@@ -52,6 +52,10 @@
 #include <mysqld_error.h>
 
 
+#define DEFAULT_CONNECT_TIMEOUT 3
+#define DEFAULT_READ_TIMEOUT 1
+#define DEFAULT_WRITE_TIMEOUT 2
+
 #define USERS_QUERY_NO_ROOT " AND user NOT IN ('root')"
 
 #if 0
@@ -105,6 +109,11 @@ void *resource_fetch(HASHTABLE *, char *);
 int resource_add(HASHTABLE *, char *, char *);
 int resource_hash(char *);
 static int normalize_hostname(char *input_host, char *output_host);
+static int gw_mysql_set_timeouts(
+	MYSQL* handle,
+	int    read_timeout,
+	int    write_timeout,
+	int    connect_timeout);
 
 /**
  * Load the user/passwd form mysql.user table into the service users' hashtable
@@ -429,7 +438,8 @@ getDatabases(SERVICE *service, MYSQL *con)
  *
  * @param service	The current service
  * @param users		The users table into which to load the users
- * @return      -1 on any error or the number of users inserted (0 means no users at all)
+ * @return      	-1 on any error or the number of users inserted 
+ * 			(0 means no users at all)
  */
 static int
 getUsers(SERVICE *service, USERS *users)
@@ -446,15 +456,19 @@ getUsers(SERVICE *service, USERS *users)
 	unsigned char	hash[SHA_DIGEST_LENGTH]="";
 	char		*users_data = NULL;
 	int 		nusers = 0;
-	int		users_data_row_len = MYSQL_USER_MAXLEN + MYSQL_HOST_MAXLEN + MYSQL_PASSWORD_LEN + sizeof(char) + MYSQL_DATABASE_MAXLEN;
+	int		users_data_row_len = MYSQL_USER_MAXLEN + 
+						MYSQL_HOST_MAXLEN + 
+						MYSQL_PASSWORD_LEN + 
+						sizeof(char) + 
+						MYSQL_DATABASE_MAXLEN;
 	int		dbnames = 0;
 	int		db_grants = 0;
 	
-	serviceGetUser(service, &service_user, &service_passwd);
+	if (serviceGetUser(service, &service_user, &service_passwd) == 0)
-
+	{
-	if (service_user == NULL || service_passwd == NULL)
+		ss_dassert(service_passwd == NULL || service_user == NULL);
 		return -1; 
-
+	}
 	con = mysql_init(NULL);
 
  	if (con == NULL) {
@@ -464,13 +478,26 @@ getUsers(SERVICE *service, USERS *users)
                         mysql_error(con))));
 		return -1;
 	}
+	/** Set read, write and connect timeout values */
+	if (gw_mysql_set_timeouts(con, 
+		DEFAULT_READ_TIMEOUT, 
+		DEFAULT_WRITE_TIMEOUT,
+		DEFAULT_CONNECT_TIMEOUT))
+	{
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : failed to set timeout values for backend "
+			"connection.")));
+		mysql_close(con);
+		return -1;
+	}
 
 	if (mysql_options(con, MYSQL_OPT_USE_REMOTE_CONNECTION, NULL)) {
 		LOGIF(LE, (skygw_log_write_flush(
                         LOGFILE_ERROR,
                         "Error : failed to set external connection. "
-                        "It is needed for backend server connections. "
+                        "It is needed for backend server connections.")));
-                        "Exiting.")));
+		mysql_close(con);
 		return -1;
 	}
 	/**
@@ -486,12 +513,26 @@ getUsers(SERVICE *service, USERS *users)
                 	server = server->nextdb;
 	}
 
+	if (service->svc_do_shutdown)
+	{
+		free(dpwd);
+		mysql_close(con);
+		return -1;
+	}
+	
 	/* Try loading data from master server */
-	if (server != NULL && (mysql_real_connect(con, server->name, service_user, dpwd, NULL, server->port, NULL, 0) != NULL)) {
+	if (server != NULL && 
+		(mysql_real_connect(con,
+			server->name, service_user, 
+			dpwd, 
+			NULL, 
+			server->port, 
+			NULL, 0) != NULL)) 
+	{
 		LOGIF(LD, (skygw_log_write_flush(
 			LOGFILE_DEBUG,
-			"Dbusers : Loading data from backend database with Master role [%s:%i] "
+			"Dbusers : Loading data from backend database with "
-			"for service [%s]",
+			"Master role [%s:%i] for service [%s]",
 			server->name,
 			server->port,
 			service->name)));
@@ -499,7 +540,9 @@ getUsers(SERVICE *service, USERS *users)
 		/* load data from other servers via loop */
 		server = service->databases;
 
-		while (server != NULL && (mysql_real_connect(con,
+		while (!service->svc_do_shutdown &&
+			server != NULL && 
+			(mysql_real_connect(con,
 					server->name,
 					service_user,
 					dpwd,
@@ -511,11 +554,18 @@ getUsers(SERVICE *service, USERS *users)
 			server = server->nextdb;
 		}
 		
+		if (service->svc_do_shutdown)
+		{
+			free(dpwd);
+			mysql_close(con);
+			return -1;
+		}
+		
 		if (server != NULL) {
 			LOGIF(LD, (skygw_log_write_flush(
 				LOGFILE_DEBUG,
-				"Dbusers : Loading data from backend database [%s:%i] "
+				"Dbusers : Loading data from backend database "
-				"for service [%s]",
+				"[%s:%i] for service [%s]",
 				server->name,
 				server->port,
 				service->name)));
@@ -535,9 +585,7 @@ getUsers(SERVICE *service, USERS *users)
 		return -1;
 	}
 
-	/* count users */
+	/** Count users. Start with users and db grants for users */
-
-	/* start with users and db grants for users */
 	if (mysql_query(con, MYSQL_USERS_WITH_DB_COUNT)) {
 		if (mysql_errno(con) != ER_TABLEACCESS_DENIED_ERROR) {
                         /* This is an error we cannot handle, return */
@@ -1213,3 +1261,58 @@ int	useorig = 0;
 
 	return netmask;
 }
+
+/**
+ * Set read, write and connect timeout values for MySQL database connection.
+ * 
+ * @param handle		MySQL handle
+ * @param read_timeout		Read timeout value in seconds
+ * @param write_timeout		Write timeout value in seconds
+ * @param connect_timeout	Connect timeout value in seconds
+ * 
+ * @return 0 if succeed, 1 if failed
+ */
+static int gw_mysql_set_timeouts(
+	MYSQL* handle,
+	int    read_timeout,
+	int    write_timeout,
+	int    connect_timeout)
+{	
+	int rc;
+	
+	if ((rc = mysql_options(handle, 
+		MYSQL_OPT_READ_TIMEOUT, 
+		(void *)&read_timeout)))
+	{
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : failed to set read timeout for backend "
+			"connection.")));
+		goto retblock;
+	}
+	
+	if ((rc = mysql_options(handle, 
+			MYSQL_OPT_CONNECT_TIMEOUT, 
+			(void *)&connect_timeout)))
+	{
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : failed to set connect timeout for backend "
+			"connection.")));
+		goto retblock;
+	}
+	
+	if ((rc = mysql_options(handle, 
+			MYSQL_OPT_WRITE_TIMEOUT, 
+			(void *)&write_timeout)))
+	{
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : failed to set write timeout for backend "
+			"connection.")));
+		goto retblock;
+	}
+	
+	retblock:
+	return rc;
+}

server/core/gateway.c

@@ -56,6 +56,7 @@
 #include <config.h>
 #include <poll.h>
 #include <housekeeper.h>
+#include <service.h>
 #include <memlog.h>
 
 #include <stdlib.h>
@@ -1837,6 +1838,7 @@ return_main:
 void
 shutdown_server()
 {
+	service_shutdown();
 	poll_shutdown();
 	hkshutdown();
 	memlog_flush_all();

server/core/service.c

@@ -87,7 +87,6 @@ static void service_add_qualified_param(
         SERVICE*          svc,
         CONFIG_PARAMETER* param);
 
-
 /**
  * Allocate a new service for the gateway to support
  *
@@ -102,7 +101,7 @@ service_alloc(const char *servname, const char *router)
 {
 SERVICE 	*service;
 
-	if ((service = (SERVICE *)malloc(sizeof(SERVICE))) == NULL)
+	if ((service = (SERVICE *)calloc(1, sizeof(SERVICE))) == NULL)
 		return NULL;
 	if ((service->router = load_module(router, MODULE_ROUTER)) == NULL)
 	{
@@ -132,27 +131,10 @@ SERVICE 	*service;
 		free(service);
 		return NULL;
 	}
-	service->version_string = NULL;
-	memset(&service->stats, 0, sizeof(SERVICE_STATS));
-	service->ports = NULL;
 	service->stats.started = time(0);
 	service->state = SERVICE_STATE_ALLOC;
-	service->credentials.name = NULL;
-	service->credentials.authdata = NULL;
-	service->enable_root = 0;
-	service->localhost_match_wildcard_host = 0;
-	service->routerOptions = NULL;
-	service->databases = NULL;
-        service->svc_config_param = NULL;
-        service->svc_config_version = 0;
-	service->filters = NULL;
-	service->n_filters = 0;
-	service->weightby = 0;
-	service->users = NULL;
-	service->resources = NULL;
 	spinlock_init(&service->spin);
 	spinlock_init(&service->users_table_spin);
-	memset(&service->rate_limit, 0, sizeof(SERVICE_REFRESH_RATE));
 
 	spinlock_acquire(&service_spin);
 	service->next = allServices;
@@ -360,7 +342,7 @@ int		listeners = 0;
 	}
 
 	port = service->ports;
-	while (port)
+	while (!service->svc_do_shutdown && port)
 	{
 		listeners += serviceStartPort(service, port);
 		port = port->next;
@@ -408,7 +390,7 @@ SERVICE	*ptr;
 int	n = 0,i;
 
 	ptr = allServices;
-	while (ptr)
+	while (ptr && !ptr->svc_do_shutdown)
 	{
 		n += (i = serviceStart(ptr));
 
@@ -1422,3 +1404,16 @@ serviceEnableLocalhostMatchWildcardHost(SERVICE *service, int action)
 
 	return 1;
 }
+
+void service_shutdown()
+{
+	SERVICE* svc;
+	spinlock_acquire(&service_spin);
+	svc = allServices;
+	while (svc != NULL)
+	{
+		svc->svc_do_shutdown = true;
+		svc = svc->next;
+	}
+	spinlock_release(&service_spin);
+}

server/include/service.h

@@ -130,6 +130,7 @@ typedef struct service {
 	CONFIG_PARAMETER*
 			svc_config_param;     /*<  list of config params and values */
 	int             svc_config_version;   /*<  Version number of configuration */
+	bool            svc_do_shutdown;	/*< tells the service to exit loops etc. */
 	SPINLOCK
 			users_table_spin;	/**< The spinlock for users data refresh */
 	SERVICE_REFRESH_RATE
@@ -186,4 +187,5 @@ extern	void	dprintService(DCB *, SERVICE *);
 extern	void	dListServices(DCB *);
 extern	void	dListListeners(DCB *);
 char* service_get_name(SERVICE* svc);
+void  service_shutdown();
 #endif