/External/Mysql-5.0/include/atomic/rwlock.h
http://awoe.googlecode.com/ · C++ Header · 57 lines · 28 code · 4 blank · 25 comment · 3 complexity · 78f69a499291ff47fdacc6eda0f7a5e0 MD5 · raw file
- /* Copyright (C) 2006 MySQL AB
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; version 2 of the License.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
- typedef struct {pthread_mutex_t rw;} my_atomic_rwlock_t;
- #define MY_ATOMIC_MODE_RWLOCKS 1
- #ifdef MY_ATOMIC_MODE_DUMMY
- /*
- the following can never be enabled by ./configure, one need to put #define in
- a source to trigger the following warning. The resulting code will be broken,
- it only makes sense to do it to see now test_atomic detects broken
- implementations (another way is to run a UP build on an SMP box).
- */
- #warning MY_ATOMIC_MODE_DUMMY and MY_ATOMIC_MODE_RWLOCKS are incompatible
- #define my_atomic_rwlock_destroy(name)
- #define my_atomic_rwlock_init(name)
- #define my_atomic_rwlock_rdlock(name)
- #define my_atomic_rwlock_wrlock(name)
- #define my_atomic_rwlock_rdunlock(name)
- #define my_atomic_rwlock_wrunlock(name)
- #define MY_ATOMIC_MODE "dummy (non-atomic)"
- #else
- /*
- we're using read-write lock macros but map them to mutex locks, and they're
- faster. Still, having semantically rich API we can change the
- underlying implementation, if necessary.
- */
- #define my_atomic_rwlock_destroy(name) pthread_mutex_destroy(& (name)->rw)
- #define my_atomic_rwlock_init(name) pthread_mutex_init(& (name)->rw, 0)
- #define my_atomic_rwlock_rdlock(name) pthread_mutex_lock(& (name)->rw)
- #define my_atomic_rwlock_wrlock(name) pthread_mutex_lock(& (name)->rw)
- #define my_atomic_rwlock_rdunlock(name) pthread_mutex_unlock(& (name)->rw)
- #define my_atomic_rwlock_wrunlock(name) pthread_mutex_unlock(& (name)->rw)
- #define MY_ATOMIC_MODE "mutex"
- #ifndef MY_ATOMIC_MODE_RWLOCKS
- #define MY_ATOMIC_MODE_RWLOCKS 1
- #endif
- #endif
- #define make_atomic_add_body(S) int ## S sav; sav= *a; *a+= v; v=sav;
- #define make_atomic_fas_body(S) int ## S sav; sav= *a; *a= v; v=sav;
- #define make_atomic_cas_body(S) if ((ret= (*a == *cmp))) *a= set; else *cmp=*a;
- #define make_atomic_load_body(S) ret= *a;
- #define make_atomic_store_body(S) *a= v;