From 066c1a3c6e1354c9d3980358f5f67429df61986d Mon Sep 17 00:00:00 2001
From: Markus Makela <markus.makela@mariadb.com>
Date: Tue, 5 May 2015 13:45:24 +0300
Subject: [PATCH] Added a warning about multiple monitors monitoring the same
 servers.

---
 server/core/config.c       | 18 +++++++++++++++++-
 server/include/hashtable.h |  6 +++++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/server/core/config.c b/server/core/config.c
index 764a606c8..4babcfdaa 100644
--- a/server/core/config.c
+++ b/server/core/config.c
@@ -301,7 +301,15 @@ process_config_context(CONFIG_CONTEXT *context)
 {
 CONFIG_CONTEXT		*obj;
 int			error_count = 0;
+HASHTABLE* monitorhash;
 
+if((monitorhash = hashtable_alloc(5,simple_str_hash,strcmp)) == NULL)
+{
+    skygw_log_write(LOGFILE_ERROR,"Error: Failed to allocate ,onitor configuration check hashtable.");
+    return 0;
+}
+
+hashtable_memory_fns(monitorhash,strdup,NULL,free,NULL);
 	/**
 	 * Process the data and create the services and servers defined
 	 * in the data.
@@ -953,6 +961,13 @@ int			error_count = 0;
                                                             obj->element && obj1->element)
                                                         {
 								found = 1;
+								if(hashtable_add(monitorhash,obj1->object,"") == 0)
+								{
+								    skygw_log_write(LOGFILE_ERROR,
+									     "Warning: Multiple monitors are monitoring server [%s]. "
+									    "This will cause undefined behavior.",
+									     obj1->object);
+								}
 								monitorAddServer(
                                                                         obj->element,
                                                                         obj1->element);
@@ -1013,7 +1028,8 @@ int			error_count = 0;
 		obj = obj->next;
 	} /*< while */
 	/** TODO: consistency check function */
-        
+
+	hashtable_free(monitorhash);
         /**
          * error_count += consistency_checks();
          */
diff --git a/server/include/hashtable.h b/server/include/hashtable.h
index a9878e3e2..26e44b799 100644
--- a/server/include/hashtable.h
+++ b/server/include/hashtable.h
@@ -96,7 +96,11 @@ HASHTABLE		*hashtable_alloc_flat(HASHTABLE* target,
 						int (*hashfn)(),
 						int (*cmpfn)());
 				/**< Allocate a hashtable */
-extern void		hashtable_memory_fns(HASHTABLE *, HASHMEMORYFN, HASHMEMORYFN, HASHMEMORYFN, HASHMEMORYFN);
+extern void		hashtable_memory_fns(HASHTABLE   *table,
+                                            HASHMEMORYFN kcopyfn,
+                                            HASHMEMORYFN vcopyfn,
+                                            HASHMEMORYFN kfreefn,
+                                            HASHMEMORYFN vfreefn);
 				/**< Provide an interface to control key/value memory
 				 * manipulation
 				 */