Fixes cases where thd->query was not protected.

This fixes a problem with SHOW PROCESSLIST


sql/log_event.cc:
  Fixes cases where thd->query was not protected
sql/sql_acl.cc:
  Table privileges was not reset on FLUSH PRIVILEGES if tables_priv was empty
sql/sql_db.cc:
  Fixes cases where thd->query was not protected

sql/log_event.cc

@@ -1702,10 +1702,11 @@ int Query_log_event::exec_event(struct st_relay_log_info* rli)
 
   if (db_ok(thd->db, replicate_do_db, replicate_ignore_db))
   {
-    thd->query = (char*)query;
     thd->set_time((time_t)when);
     thd->current_tablenr = 0;
+    thd->query_length= q_len;
     VOID(pthread_mutex_lock(&LOCK_thread_count));
+    thd->query = (char*)query;
     thd->query_id = query_id++;
     VOID(pthread_mutex_unlock(&LOCK_thread_count));
     thd->query_error = 0;			// clear error
@@ -1760,7 +1761,9 @@ int Query_log_event::exec_event(struct st_relay_log_info* rli)
     else
     {
       // master could be inconsistent, abort and tell DBA to check/fix it
+      VOID(pthread_mutex_lock(&LOCK_thread_count));
       thd->db = thd->query = 0;
+      VOID(pthread_mutex_unlock(&LOCK_thread_count));
       thd->variables.convert_set = 0;
       close_thread_tables(thd);
       free_root(&thd->mem_root,0);
@@ -1768,7 +1771,9 @@ int Query_log_event::exec_event(struct st_relay_log_info* rli)
     }
   }
   thd->db= 0;				// prevent db from being freed
+  VOID(pthread_mutex_lock(&LOCK_thread_count));
   thd->query= 0;			// just to be sure
+  VOID(pthread_mutex_unlock(&LOCK_thread_count));
   // assume no convert for next query unless set explictly
   thd->variables.convert_set = 0;
   close_thread_tables(thd);
@@ -1816,7 +1821,8 @@ int Load_log_event::exec_event(NET* net, struct st_relay_log_info* rli,
 {
   init_sql_alloc(&thd->mem_root, 8192,0);
   thd->db = rewrite_db((char*)db);
-  thd->query = 0;
+  DBUG_ASSERT(thd->query == 0);
+  thd->query = 0;				// Should not be needed
   thd->query_error = 0;
 	    
   if (db_ok(thd->db, replicate_do_db, replicate_ignore_db))

sql/sql_acl.cc

@@ -2322,6 +2322,7 @@ my_bool grant_init(THD *org_thd)
   if (t_table->file->index_first(t_table->record[0]))
   {
     t_table->file->index_end();
+    return_val= 0;
     goto end_unlock;
   }
   grant_option= TRUE;

sql/sql_db.cc

@@ -78,9 +78,9 @@ int mysql_create_db(THD *thd, char *db, uint create_options, bool silent)
     if (!thd->query)
     {
       /* The client used the old obsolete mysql_create_db() call */
-      thd->query_length = (uint) (strxmov(path,"create database `", db, "`",
-					  NullS) - path);
-      thd->query = path;
+      thd->query_length= (uint) (strxmov(path,"create database `", db, "`",
+					 NullS) - path);
+      thd->query= path;
     }
     {
       mysql_update_log.write(thd,thd->query, thd->query_length);
@@ -93,7 +93,7 @@ int mysql_create_db(THD *thd, char *db, uint create_options, bool silent)
     if (thd->query == path)
     {
       VOID(pthread_mutex_lock(&LOCK_thread_count));
-      thd->query = 0; // just in case
+      thd->query= 0;
       VOID(pthread_mutex_unlock(&LOCK_thread_count));
     }
     send_ok(&thd->net, result);
@@ -182,7 +182,7 @@ int mysql_rm_db(THD *thd,char *db,bool if_exists, bool silent)
       if (thd->query == path)
       {
 	VOID(pthread_mutex_lock(&LOCK_thread_count));
-	thd->query = 0; // just in case
+	thd->query= 0;
 	VOID(pthread_mutex_unlock(&LOCK_thread_count));
       }
       send_ok(&thd->net,(ulong) deleted);