1 #ifndef SYS_VARS_SHARED_INCLUDED
2 #define SYS_VARS_SHARED_INCLUDED
3 
4 /* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; version 2 of the License.
9 
10    This program is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13    GNU General Public License for more details.
14 
15    You should have received a copy of the GNU General Public License
16    along with this program; if not, write to the Free Software
17    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
18 
19 /**
20   @file
21   "protected" interface to sys_var - server configuration variables.
22 
23   This header is included by files implementing support and utility
24   functions of sys_var's (set_var.cc) and files implementing
25   classes in the sys_var hierarchy (sql_plugin.cc)
26 */
27 
28 #include <sql_priv.h>
29 #include "set_var.h"
30 
31 extern bool throw_bounds_warning(THD *thd, const char *name,const char *v);
32 extern bool throw_bounds_warning(THD *thd, const char *name,
33                                  bool fixed, bool is_unsigned, longlong v);
34 extern bool throw_bounds_warning(THD *thd, const char *name, bool fixed,
35                                  double v);
36 extern sys_var *intern_find_sys_var(const char *str, size_t length);
37 
38 extern sys_var_chain all_sys_vars;
39 
40 /** wrapper to hide a mutex and an rwlock under a common interface */
41 class PolyLock
42 {
43 public:
44   virtual void rdlock()= 0;
45   virtual void wrlock()= 0;
46   virtual void unlock()= 0;
~PolyLock()47   virtual ~PolyLock() {}
48 };
49 
50 class PolyLock_mutex: public PolyLock
51 {
52   mysql_mutex_t *mutex;
53 public:
PolyLock_mutex(mysql_mutex_t * arg)54   PolyLock_mutex(mysql_mutex_t *arg): mutex(arg) {}
rdlock()55   void rdlock() { mysql_mutex_lock(mutex); }
wrlock()56   void wrlock() { mysql_mutex_lock(mutex); }
unlock()57   void unlock() { mysql_mutex_unlock(mutex); }
58 };
59 
60 class PolyLock_rwlock: public PolyLock
61 {
62   mysql_rwlock_t *rwlock;
63 public:
PolyLock_rwlock(mysql_rwlock_t * arg)64   PolyLock_rwlock(mysql_rwlock_t *arg): rwlock(arg) {}
rdlock()65   void rdlock() { mysql_rwlock_rdlock(rwlock); }
wrlock()66   void wrlock() { mysql_rwlock_wrlock(rwlock); }
unlock()67   void unlock() { mysql_rwlock_unlock(rwlock); }
68 };
69 
70 class AutoWLock
71 {
72   PolyLock *lock;
73 public:
AutoWLock(PolyLock * l)74   AutoWLock(PolyLock *l) : lock(l) { if (lock) lock->wrlock(); }
~AutoWLock()75   ~AutoWLock() { if (lock) lock->unlock(); }
76 };
77 
78 class AutoRLock
79 {
80   PolyLock *lock;
81 public:
AutoRLock(PolyLock * l)82   AutoRLock(PolyLock *l) : lock(l) { if (lock) lock->rdlock(); }
~AutoRLock()83   ~AutoRLock() { if (lock) lock->unlock(); }
84 };
85 
86 
87 #endif /* SYS_VARS_SHARED_INCLUDED */
88