 e41589be10
			
		
	
	e41589be10
	
	
	
		
			
			- Headers now to be included as <maxscale/xyz.h> - First step, no cleanup of headers has been made. Only moving from one place to another + necessary modifications.
		
			
				
	
	
		
			793 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			793 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2016 MariaDB Corporation Ab
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|  *
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|  * Use of this software is governed by the Business Source License included
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|  * in the LICENSE.TXT file and at www.mariadb.com/bsl.
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|  *
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|  * Change Date: 2019-07-01
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|  *
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|  * On the date above, in accordance with the Business Source License, use
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|  * of this software will be governed by version 2 or later of the General
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|  * Public License.
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|  */
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| 
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| /**
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|  * @file mm_mon.c - A Multi-Master Multi Muster cluster monitor
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|  *
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|  * @verbatim
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|  * Revision History
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|  *
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|  * Date     Who                 Description
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|  * 08/09/14 Massimiliano Pinto  Initial implementation
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|  * 08/05/15 Markus Makela       Addition of launchable scripts
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|  * 17/10/15 Martin Brampton     Change DCB callback to hangup
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|  *
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|  * @endverbatim
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|  */
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| 
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| #include "mmmon.h"
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| #include <maxscale/dcb.h>
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| #include <maxscale/alloc.h>
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| 
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| static void monitorMain(void *);
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| 
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| static char *version_str = "V1.1.1";
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| 
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| /* @see function load_module in load_utils.c for explanation of the following
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|  * lint directives.
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|  */
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| /*lint -e14 */
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| MODULE_INFO info =
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| {
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|     MODULE_API_MONITOR,
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|     MODULE_BETA_RELEASE,
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|     MONITOR_VERSION,
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|     "A Multi-Master Multi Master monitor"
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| };
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| /*lint +e14 */
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| 
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| static void *startMonitor(MONITOR *, const CONFIG_PARAMETER *);
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| static void stopMonitor(MONITOR *);
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| static void diagnostics(DCB *, const MONITOR *);
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| static void detectStaleMaster(void *, int);
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| static MONITOR_SERVERS *get_current_master(MONITOR *);
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| static bool isMySQLEvent(monitor_event_t event);
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| 
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| static MONITOR_OBJECT MyObject =
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| {
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|     startMonitor,
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|     stopMonitor,
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|     diagnostics
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| };
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| 
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| /**
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|  * Implementation of the mandatory version entry point
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|  *
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|  * @return version string of the module
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|  *
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|  * @see function load_module in load_utils.c for explanation of the following
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|  * lint directives.
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|  */
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| /*lint -e14 */
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| char *
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| version()
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| {
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|     return version_str;
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| }
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| 
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| /**
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|  * The module initialisation routine, called when the module
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|  * is first loaded.
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|  */
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| void
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| ModuleInit()
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| {
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|     MXS_NOTICE("Initialise the Multi-Master Monitor module %s.", version_str);
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| }
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| 
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| /**
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|  * The module entry point routine. It is this routine that
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|  * must populate the structure that is referred to as the
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|  * "module object", this is a structure with the set of
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|  * external entry points for this module.
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|  *
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|  * @return The module object
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|  */
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| MONITOR_OBJECT *
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| GetModuleObject()
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| {
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|     return &MyObject;
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| }
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| /*lint +e14 */
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| 
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| /**
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|  * Start the instance of the monitor, returning a handle on the monitor.
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|  *
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|  * This function creates a thread to execute the actual monitoring.
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|  *
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|  * @param arg   The current handle - NULL if first start
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|  * @return A handle to use when interacting with the monitor
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|  */
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| static void *
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| startMonitor(MONITOR *mon, const CONFIG_PARAMETER *params)
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| {
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|     MM_MONITOR *handle = mon->handle;
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|     bool have_events = false, script_error = false;
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| 
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|     if (handle)
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|     {
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|         handle->shutdown = 0;
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|     }
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|     else
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|     {
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|         if ((handle = (MM_MONITOR *) MXS_MALLOC(sizeof(MM_MONITOR))) == NULL)
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|         {
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|             return NULL;
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|         }
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|         handle->shutdown = 0;
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|         handle->id = MONITOR_DEFAULT_ID;
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|         handle->master = NULL;
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|         handle->script = NULL;
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|         handle->detectStaleMaster = false;
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|         memset(handle->events, false, sizeof(handle->events));
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|         spinlock_init(&handle->lock);
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|     }
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| 
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|     while (params)
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|     {
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|         if (!strcmp(params->name, "detect_stale_master"))
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|         {
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|             handle->detectStaleMaster = config_truth_value(params->value);
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|         }
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|         else if (!strcmp(params->name, "script"))
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|         {
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|             if (externcmd_can_execute(params->value))
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|             {
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|                 MXS_FREE(handle->script);
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|                 handle->script = MXS_STRDUP_A(params->value);
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|             }
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|             else
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|             {
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|                 script_error = true;
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|             }
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|         }
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|         else if (!strcmp(params->name, "events"))
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|         {
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|             if (mon_parse_event_string((bool *)handle->events,
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|                                        sizeof(handle->events), params->value) != 0)
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|             {
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|                 script_error = true;
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|             }
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|             else
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|             {
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|                 have_events = true;
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|             }
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|         }
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|         params = params->next;
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|     }
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| 
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|     if (!check_monitor_permissions(mon, "SHOW SLAVE STATUS"))
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|     {
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|         MXS_ERROR("Failed to start monitor. See earlier errors for more information.");
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|         MXS_FREE(handle->script);
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|         MXS_FREE(handle);
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|         return NULL;
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|     }
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| 
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|     if (script_error)
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|     {
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|         MXS_ERROR("Errors were found in the script configuration parameters "
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|                   "for the monitor '%s'. The script will not be used.", mon->name);
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|         MXS_FREE(handle->script);
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|         handle->script = NULL;
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|     }
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|     /** If no specific events are given, enable them all */
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|     if (!have_events)
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|     {
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|         memset(handle->events, true, sizeof(handle->events));
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|     }
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| 
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|     if (thread_start(&handle->thread, monitorMain, mon) == NULL)
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|     {
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|         MXS_ERROR("Failed to start monitor thread for monitor '%s'.", mon->name);
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|     }
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| 
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|     return handle;
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| }
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| 
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| /**
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|  * Stop a running monitor
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|  *
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|  * @param arg   Handle on thr running monior
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|  */
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| static void
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| stopMonitor(MONITOR *mon)
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| {
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|     MM_MONITOR *handle = (MM_MONITOR *) mon->handle;
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| 
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|     handle->shutdown = 1;
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|     thread_wait(handle->thread);
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| }
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| 
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| /**
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|  * Daignostic interface
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|  *
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|  * @param dcb   DCB to print diagnostics
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|  * @param arg   The monitor handle
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|  */
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| static void diagnostics(DCB *dcb, const MONITOR *mon)
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| {
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|     const MM_MONITOR *handle = (const MM_MONITOR *) mon->handle;
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|     MONITOR_SERVERS *db;
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|     char *sep;
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| 
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|     switch (handle->status)
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|     {
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|         case MONITOR_RUNNING:
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|             dcb_printf(dcb, "\tMonitor running\n");
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|             break;
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|         case MONITOR_STOPPING:
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|             dcb_printf(dcb, "\tMonitor stopping\n");
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|             break;
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|         case MONITOR_STOPPED:
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|             dcb_printf(dcb, "\tMonitor stopped\n");
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|             break;
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|     }
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| 
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|     dcb_printf(dcb, "\tSampling interval:\t%lu milliseconds\n", mon->interval);
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|     dcb_printf(dcb, "\tDetect Stale Master:\t%s\n", (handle->detectStaleMaster == 1) ? "enabled" : "disabled");
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|     dcb_printf(dcb, "\tMonitored servers:	");
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| 
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|     db = mon->databases;
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|     sep = "";
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|     while (db)
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|     {
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|         dcb_printf(dcb, "%s%s:%d", sep, db->server->name, db->server->port);
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|         sep = ", ";
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|         db = db->next;
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|     }
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|     dcb_printf(dcb, "\n");
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| }
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| 
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| /**
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|  * Monitor an individual server
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|  *
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|  * @param handle        The MySQL Monitor object
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|  * @param database  The database to probe
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|  */
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| static void
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| monitorDatabase(MONITOR* mon, MONITOR_SERVERS *database)
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| {
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|     MYSQL_ROW row;
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|     MYSQL_RES *result;
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|     int isslave = 0;
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|     int ismaster = 0;
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|     unsigned long int server_version = 0;
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|     char *server_string;
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| 
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|     /* Don't probe servers in maintenance mode */
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|     if (SERVER_IN_MAINT(database->server))
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|     {
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|         return;
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|     }
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| 
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|     /** Store previous status */
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|     database->mon_prev_status = database->server->status;
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|     connect_result_t rval = mon_connect_to_db(mon, database);
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| 
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|     if (rval != MONITOR_CONN_OK)
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|     {
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|         if (mysql_errno(database->con) == ER_ACCESS_DENIED_ERROR)
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|         {
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|             server_set_status(database->server, SERVER_AUTH_ERROR);
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|             monitor_set_pending_status(database, SERVER_AUTH_ERROR);
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|         }
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|         server_clear_status(database->server, SERVER_RUNNING);
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|         monitor_clear_pending_status(database, SERVER_RUNNING);
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| 
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|         /* Also clear M/S state in both server and monitor server pending struct */
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|         server_clear_status(database->server, SERVER_SLAVE);
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|         server_clear_status(database->server, SERVER_MASTER);
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|         monitor_clear_pending_status(database, SERVER_SLAVE);
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|         monitor_clear_pending_status(database, SERVER_MASTER);
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| 
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|         /* Clean addition status too */
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|         server_clear_status(database->server, SERVER_STALE_STATUS);
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|         monitor_clear_pending_status(database, SERVER_STALE_STATUS);
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| 
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|         if (mon_status_changed(database) && mon_print_fail_status(database))
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|         {
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|             mon_log_connect_error(database, rval);
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|         }
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|         return;
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|     }
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|     else
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|     {
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|         server_clear_status(database->server, SERVER_AUTH_ERROR);
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|         monitor_clear_pending_status(database, SERVER_AUTH_ERROR);
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|     }
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| 
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|     /* Store current status in both server and monitor server pending struct */
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|     server_set_status(database->server, SERVER_RUNNING);
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|     monitor_set_pending_status(database, SERVER_RUNNING);
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| 
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|     /* get server version from current server */
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|     server_version = mysql_get_server_version(database->con);
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| 
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|     /* get server version string */
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|     server_string = (char *) mysql_get_server_info(database->con);
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|     if (server_string)
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|     {
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|         server_set_version_string(database->server, server_string);
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|     }
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| 
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|     /* get server_id form current node */
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|     if (mysql_query(database->con, "SELECT @@server_id") == 0
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|         && (result = mysql_store_result(database->con)) != NULL)
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|     {
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|         long server_id = -1;
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| 
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|         if (mysql_field_count(database->con) != 1)
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|         {
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|             mysql_free_result(result);
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|             MXS_ERROR("Unexpected result for 'SELECT @@server_id'. Expected 1 column."
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|                       " MySQL Version: %s", version_str);
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|             return;
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|         }
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| 
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|         while ((row = mysql_fetch_row(result)))
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|         {
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|             server_id = strtol(row[0], NULL, 10);
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|             if ((errno == ERANGE && (server_id == LONG_MAX
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|                                      || server_id == LONG_MIN)) || (errno != 0 && server_id == 0))
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|             {
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|                 server_id = -1;
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|             }
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|             database->server->node_id = server_id;
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|         }
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|         mysql_free_result(result);
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|     }
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| 
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|     /* Check if the Slave_SQL_Running and Slave_IO_Running status is
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|      * set to Yes
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|      */
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| 
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|     /* Check first for MariaDB 10.x.x and get status for multimaster replication */
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|     if (server_version >= 100000)
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|     {
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| 
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|         if (mysql_query(database->con, "SHOW ALL SLAVES STATUS") == 0
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|             && (result = mysql_store_result(database->con)) != NULL)
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|         {
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|             int i = 0;
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|             long master_id = -1;
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| 
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|             if (mysql_field_count(database->con) < 42)
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|             {
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|                 mysql_free_result(result);
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|                 MXS_ERROR("\"SHOW ALL SLAVES STATUS\" returned less than the expected"
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|                           " amount of columns. Expected 42 columns MySQL Version: %s",
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|                           version_str);
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|                 return;
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|             }
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| 
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|             while ((row = mysql_fetch_row(result)))
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|             {
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|                 /* get Slave_IO_Running and Slave_SQL_Running values*/
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|                 if (strncmp(row[12], "Yes", 3) == 0
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|                     && strncmp(row[13], "Yes", 3) == 0)
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|                 {
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|                     isslave += 1;
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|                 }
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| 
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|                 /* If Slave_IO_Running = Yes, assign the master_id to current server: this allows building
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|                  * the replication tree, slaves ids will be added to master(s) and we will have at least the
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|                  * root master server.
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|                  * Please note, there could be no slaves at all if Slave_SQL_Running == 'No'
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|                  */
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|                 if (strncmp(row[12], "Yes", 3) == 0)
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|                 {
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|                     /* get Master_Server_Id values */
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|                     master_id = atol(row[41]);
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|                     if (master_id == 0)
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|                     {
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|                         master_id = -1;
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|                     }
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|                 }
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| 
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|                 i++;
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|             }
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|             /* store master_id of current node */
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|             memcpy(&database->server->master_id, &master_id, sizeof(long));
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| 
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|             mysql_free_result(result);
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| 
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|             /* If all configured slaves are running set this node as slave */
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|             if (isslave > 0 && isslave == i)
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|             {
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|                 isslave = 1;
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|             }
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|             else
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|             {
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|                 isslave = 0;
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|             }
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|         }
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|     }
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|     else
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|     {
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|         if (mysql_query(database->con, "SHOW SLAVE STATUS") == 0
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|             && (result = mysql_store_result(database->con)) != NULL)
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|         {
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|             long master_id = -1;
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| 
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|             if (mysql_field_count(database->con) < 40)
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|             {
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|                 mysql_free_result(result);
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| 
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|                 if (server_version < 5 * 10000 + 5 * 100)
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|                 {
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|                     if (database->log_version_err)
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|                     {
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|                         MXS_ERROR("\"SHOW SLAVE STATUS\" "
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|                                   " for versions less than 5.5 does not have master_server_id, "
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|                                   "replication tree cannot be resolved for server %s."
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|                                   " MySQL Version: %s", database->server->unique_name, version_str);
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|                         database->log_version_err = false;
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|                     }
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|                 }
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|                 else
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|                 {
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|                     MXS_ERROR("\"SHOW SLAVE STATUS\" "
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|                               "returned less than the expected amount of columns. "
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|                               "Expected 40 columns. MySQL Version: %s", version_str);
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|                 }
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|                 return;
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|             }
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| 
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|             while ((row = mysql_fetch_row(result)))
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|             {
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|                 /* get Slave_IO_Running and Slave_SQL_Running values*/
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|                 if (strncmp(row[10], "Yes", 3) == 0
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|                     && strncmp(row[11], "Yes", 3) == 0)
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|                 {
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|                     isslave = 1;
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|                 }
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| 
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|                 /* If Slave_IO_Running = Yes, assign the master_id to current server: this allows building
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|                  * the replication tree, slaves ids will be added to master(s) and we will have at least the
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|                  * root master server.
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|                  * Please note, there could be no slaves at all if Slave_SQL_Running == 'No'
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|                  */
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|                 if (strncmp(row[10], "Yes", 3) == 0)
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|                 {
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|                     /* get Master_Server_Id values */
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|                     master_id = atol(row[39]);
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|                     if (master_id == 0)
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|                     {
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|                         master_id = -1;
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|                     }
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|                 }
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|             }
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|             /* store master_id of current node */
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|             memcpy(&database->server->master_id, &master_id, sizeof(long));
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| 
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|             mysql_free_result(result);
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|         }
 | |
|     }
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| 
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|     /* get variable 'read_only' set by an external component */
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|     if (mysql_query(database->con, "SHOW GLOBAL VARIABLES LIKE 'read_only'") == 0
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|         && (result = mysql_store_result(database->con)) != NULL)
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|     {
 | |
|         if (mysql_field_count(database->con) < 2)
 | |
|         {
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|             mysql_free_result(result);
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|             MXS_ERROR("Unexpected result for \"SHOW GLOBAL VARIABLES LIKE 'read_only'\". "
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|                       "Expected 2 columns. MySQL Version: %s", version_str);
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|             return;
 | |
|         }
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| 
 | |
|         while ((row = mysql_fetch_row(result)))
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|         {
 | |
|             if (strncasecmp(row[1], "OFF", 3) == 0)
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|             {
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|                 ismaster = 1;
 | |
|             }
 | |
|             else
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|             {
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|                 isslave = 1;
 | |
|             }
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|         }
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|         mysql_free_result(result);
 | |
|     }
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| 
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|     /* Remove addition info */
 | |
|     monitor_clear_pending_status(database, SERVER_STALE_STATUS);
 | |
| 
 | |
|     /* Set the Slave Role */
 | |
|     /* Set the Master role */
 | |
|     if (ismaster)
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|     {
 | |
|         monitor_clear_pending_status(database, SERVER_SLAVE);
 | |
|         monitor_set_pending_status(database, SERVER_MASTER);
 | |
| 
 | |
|         /* Set replication depth to 0 */
 | |
|         database->server->depth = 0;
 | |
|     }
 | |
|     else if (isslave)
 | |
|     {
 | |
|         monitor_set_pending_status(database, SERVER_SLAVE);
 | |
|         /* Avoid any possible stale Master state */
 | |
|         monitor_clear_pending_status(database, SERVER_MASTER);
 | |
| 
 | |
|         /* Set replication depth to 1 */
 | |
|         database->server->depth = 1;
 | |
|     }
 | |
|     /* Avoid any possible Master/Slave stale state */
 | |
|     else
 | |
|     {
 | |
|         monitor_clear_pending_status(database, SERVER_SLAVE);
 | |
|         monitor_clear_pending_status(database, SERVER_MASTER);
 | |
|     }
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * The entry point for the monitoring module thread
 | |
|  *
 | |
|  * @param arg   The handle of the monitor
 | |
|  */
 | |
| static void
 | |
| monitorMain(void *arg)
 | |
| {
 | |
|     MONITOR* mon = (MONITOR*) arg;
 | |
|     MM_MONITOR *handle;
 | |
|     MONITOR_SERVERS *ptr;
 | |
|     int detect_stale_master = false;
 | |
|     MONITOR_SERVERS *root_master = NULL;
 | |
|     size_t nrounds = 0;
 | |
| 
 | |
|     spinlock_acquire(&mon->lock);
 | |
|     handle = (MM_MONITOR *) mon->handle;
 | |
|     spinlock_release(&mon->lock);
 | |
|     detect_stale_master = handle->detectStaleMaster;
 | |
| 
 | |
|     if (mysql_thread_init())
 | |
|     {
 | |
|         MXS_ERROR("Fatal : mysql_thread_init failed in monitor module. Exiting.");
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     handle->status = MONITOR_RUNNING;
 | |
|     while (1)
 | |
|     {
 | |
|         if (handle->shutdown)
 | |
|         {
 | |
|             handle->status = MONITOR_STOPPING;
 | |
|             mysql_thread_end();
 | |
|             handle->status = MONITOR_STOPPED;
 | |
|             return;
 | |
|         }
 | |
| 
 | |
|         /** Wait base interval */
 | |
|         thread_millisleep(MON_BASE_INTERVAL_MS);
 | |
|         /**
 | |
|          * Calculate how far away the monitor interval is from its full
 | |
|          * cycle and if monitor interval time further than the base
 | |
|          * interval, then skip monitoring checks. Excluding the first
 | |
|          * round.
 | |
|          */
 | |
|         if (nrounds != 0 &&
 | |
|             ((nrounds * MON_BASE_INTERVAL_MS) % mon->interval) >=
 | |
|             MON_BASE_INTERVAL_MS)
 | |
|         {
 | |
|             nrounds += 1;
 | |
|             continue;
 | |
|         }
 | |
|         nrounds += 1;
 | |
| 
 | |
|         /* start from the first server in the list */
 | |
|         ptr = mon->databases;
 | |
| 
 | |
|         while (ptr)
 | |
|         {
 | |
|             /* copy server status into monitor pending_status */
 | |
|             ptr->pending_status = ptr->server->status;
 | |
| 
 | |
|             /* monitor current node */
 | |
|             monitorDatabase(mon, ptr);
 | |
| 
 | |
|             if (mon_status_changed(ptr))
 | |
|             {
 | |
|                 if (!(SERVER_IS_RUNNING(ptr->server)) ||
 | |
|                     !(SERVER_IS_IN_CLUSTER(ptr->server)))
 | |
|                 {
 | |
|                     dcb_hangup_foreach(ptr->server);
 | |
|                 }
 | |
|             }
 | |
| 
 | |
|             if (mon_status_changed(ptr) ||
 | |
|                 mon_print_fail_status(ptr))
 | |
|             {
 | |
|                 MXS_DEBUG("Backend server %s:%d state : %s",
 | |
|                           ptr->server->name,
 | |
|                           ptr->server->port,
 | |
|                           STRSRVSTATUS(ptr->server));
 | |
|             }
 | |
|             if (SERVER_IS_DOWN(ptr->server))
 | |
|             {
 | |
|                 /** Increase this server'e error count */
 | |
|                 ptr->mon_err_count += 1;
 | |
|             }
 | |
|             else
 | |
|             {
 | |
|                 /** Reset this server's error count */
 | |
|                 ptr->mon_err_count = 0;
 | |
|             }
 | |
| 
 | |
|             ptr = ptr->next;
 | |
|         }
 | |
| 
 | |
|         /* Get Master server pointer */
 | |
|         root_master = get_current_master(mon);
 | |
| 
 | |
|         /* Update server status from monitor pending status on that server*/
 | |
| 
 | |
|         ptr = mon->databases;
 | |
|         while (ptr)
 | |
|         {
 | |
|             if (!SERVER_IN_MAINT(ptr->server))
 | |
|             {
 | |
|                 /* If "detect_stale_master" option is On, let's use the previus master */
 | |
|                 if (detect_stale_master && root_master &&
 | |
|                     (!strcmp(ptr->server->name, root_master->server->name) &&
 | |
|                      ptr->server->port == root_master->server->port) && (ptr->server->status & SERVER_MASTER) &&
 | |
|                     !(ptr->pending_status & SERVER_MASTER))
 | |
|                 {
 | |
|                     /* in this case server->status will not be updated from pending_status */
 | |
|                     MXS_NOTICE("[mysql_mon]: root server [%s:%i] is no longer Master, let's "
 | |
|                                "use it again even if it could be a stale master, you have "
 | |
|                                "been warned!", ptr->server->name, ptr->server->port);
 | |
|                     /* Set the STALE bit for this server in server struct */
 | |
|                     server_set_status(ptr->server, SERVER_STALE_STATUS);
 | |
|                 }
 | |
|                 else
 | |
|                 {
 | |
|                     ptr->server->status = ptr->pending_status;
 | |
|                 }
 | |
|             }
 | |
|             ptr = ptr->next;
 | |
|         }
 | |
| 
 | |
|         ptr = mon->databases;
 | |
|         monitor_event_t evtype;
 | |
|         while (ptr)
 | |
|         {
 | |
|             if (mon_status_changed(ptr))
 | |
|             {
 | |
|                 evtype = mon_get_event_type(ptr);
 | |
|                 if (isMySQLEvent(evtype))
 | |
|                 {
 | |
|                     mon_log_state_change(ptr);
 | |
|                     if (handle->script && handle->events[evtype])
 | |
|                     {
 | |
|                         monitor_launch_script(mon, ptr, handle->script);
 | |
|                     }
 | |
|                 }
 | |
|             }
 | |
|             ptr = ptr->next;
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * Enable/Disable the MySQL Replication Stale Master dectection, allowing a previouvsly detected master to still act as a Master.
 | |
|  * This option must be enabled in order to keep the Master when the replication is stopped or removed from slaves.
 | |
|  * If the replication is still stopped when MaxSclale is restarted no Master will be available.
 | |
|  *
 | |
|  * @param arg       The handle allocated by startMonitor
 | |
|  * @param enable    To enable it 1, disable it with 0
 | |
|  */
 | |
| /* Not used
 | |
| static void
 | |
| detectStaleMaster(void *arg, int enable)
 | |
| {
 | |
|     MONITOR* mon = (MONITOR*) arg;
 | |
|     MM_MONITOR *handle = (MM_MONITOR *) mon->handle;
 | |
|     memcpy(&handle->detectStaleMaster, &enable, sizeof(int));
 | |
| }
 | |
| */
 | |
| 
 | |
| /*******
 | |
|  * This function returns the master server
 | |
|  * from a set of MySQL Multi Master monitored servers
 | |
|  * and returns the root server (that has SERVER_MASTER bit)
 | |
|  * The server is returned even for servers in 'maintenance' mode.
 | |
|  *
 | |
|  * @param handle        The monitor handle
 | |
|  * @return              The server at root level with SERVER_MASTER bit
 | |
|  */
 | |
| 
 | |
| static MONITOR_SERVERS *get_current_master(MONITOR *mon)
 | |
| {
 | |
|     MM_MONITOR* handle = mon->handle;
 | |
|     MONITOR_SERVERS *ptr;
 | |
| 
 | |
|     ptr = mon->databases;
 | |
| 
 | |
|     while (ptr)
 | |
|     {
 | |
|         /* The server could be in SERVER_IN_MAINT
 | |
|          * that means SERVER_IS_RUNNING returns 0
 | |
|          * Let's check only for SERVER_IS_DOWN: server is not running
 | |
|          */
 | |
|         if (SERVER_IS_DOWN(ptr->server))
 | |
|         {
 | |
|             ptr = ptr->next;
 | |
|             continue;
 | |
|         }
 | |
| 
 | |
|         if (ptr->server->depth == 0)
 | |
|         {
 | |
|             handle->master = ptr;
 | |
|         }
 | |
| 
 | |
|         ptr = ptr->next;
 | |
|     }
 | |
| 
 | |
| 
 | |
|     /*
 | |
|      * Return the root master
 | |
|      */
 | |
| 
 | |
|     if (handle->master != NULL)
 | |
|     {
 | |
|         /* If the root master is in MAINT, return NULL */
 | |
|         if (SERVER_IN_MAINT(handle->master->server))
 | |
|         {
 | |
|             return NULL;
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|             return handle->master;
 | |
|         }
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|         return NULL;
 | |
|     }
 | |
| }
 | |
| 
 | |
| 
 | |
| static monitor_event_t mysql_events[] =
 | |
| {
 | |
|     MASTER_DOWN_EVENT,
 | |
|     MASTER_UP_EVENT,
 | |
|     SLAVE_DOWN_EVENT,
 | |
|     SLAVE_UP_EVENT,
 | |
|     SERVER_DOWN_EVENT,
 | |
|     SERVER_UP_EVENT,
 | |
|     LOST_MASTER_EVENT,
 | |
|     LOST_SLAVE_EVENT,
 | |
|     NEW_MASTER_EVENT,
 | |
|     NEW_SLAVE_EVENT,
 | |
|     MAX_MONITOR_EVENT
 | |
| };
 | |
| 
 | |
| /**
 | |
|  * Check if the MM monitor is monitoring this event type.
 | |
|  * @param event Event to check
 | |
|  * @return True if the event is monitored, false if it is not
 | |
|  * */
 | |
| bool isMySQLEvent(monitor_event_t event)
 | |
| {
 | |
|     int i;
 | |
|     for (i = 0; mysql_events[i] != MAX_MONITOR_EVENT; i++)
 | |
|     {
 | |
|         if (event == mysql_events[i])
 | |
|         {
 | |
|             return true;
 | |
|         }
 | |
|     }
 | |
|     return false;
 | |
| }
 |