lumiera_/src/lib/rwlock.h
2010-01-10 10:36:24 +01:00

176 lines
9.8 KiB
C

/*
rwlock.h - read/write locks
Copyright (C) Lumiera.org
2008, Christian Thaeter <ct@pipapo.org>
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; either version 2 of the
License, or (at your option) any later version.
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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef LUMIERA_RWLOCK_H
#define LUMIERA_RWLOCK_H
#ifndef _GNU_SOURCE
#error "This header must be included with _GNU_SOURCE or _POSIX_C_SOURCE >= 200112L defined"
#endif
#include <pthread.h>
#include <nobug.h>
LUMIERA_ERROR_DECLARE(RWLOCK_AGAIN);
LUMIERA_ERROR_DECLARE(RWLOCK_DEADLOCK);
LUMIERA_ERROR_DECLARE(RWLOCK_DESTROY);
LUMIERA_ERROR_DECLARE(RWLOCK_UNLOCK);
LUMIERA_ERROR_DECLARE(RWLOCK_RDLOCK);
LUMIERA_ERROR_DECLARE(RWLOCK_WRLOCK);
/**
* @file
* Read/write locks, header.
*/
/**
* Read locked section.
*/
#define LUMIERA_RDLOCK_SECTION(nobugflag, rwlck) \
for (lumiera_sectionlock NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) \
lumiera_lock_section_ = { \
rwlck, lumiera_rwlock_unlock_cb NOBUG_ALPHA_COMMA(&NOBUG_FLAG(nobugflag)) NOBUG_ALPHA_COMMA_NULL}; \
({ \
if (lumiera_lock_section_.lock) \
{ \
RESOURCE_WAIT (nobugflag, (rwlck)->rh, "acquire readlock", lumiera_lock_section_.rh); \
if (pthread_rwlock_rdlock (&(rwlck)->rwlock)) \
LUMIERA_DIE (LOCK_ACQUIRE); \
RESOURCE_STATE (nobugflag, NOBUG_RESOURCE_SHARED, lumiera_lock_section_.rh); \
} \
lumiera_lock_section_.lock; \
}); \
({ \
LUMIERA_RWLOCK_SECTION_UNLOCK; \
}))
#define LUMIERA_RDLOCK_SECTION_CHAIN(nobugflag, rwlck) \
for (lumiera_sectionlock *lumiera_lock_section_old_ = &lumiera_lock_section_, \
NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) lumiera_lock_section_ = { \
rwlck, lumiera_rwlock_unlock_cb NOBUG_ALPHA_COMMA(&NOBUG_FLAG(nobugflag)) NOBUG_ALPHA_COMMA_NULL}; \
({ \
if (lumiera_lock_section_.lock) \
{ \
REQUIRE (lumiera_lock_section_old_->lock, "section prematurely unlocked"); \
RESOURCE_WAIT (nobugflag, (rwlck)->rh, "acquire readlock", lumiera_lock_section_.rh); \
if (pthread_rwlock_rdlock (&(rwlck)->rwlock)) \
LUMIERA_DIE (LOCK_ACQUIRE); \
RESOURCE_STATE (nobugflag, NOBUG_RESOURCE_SHARED, lumiera_lock_section_.rh); \
LUMIERA_SECTION_UNLOCK_(lumiera_lock_section_old_); \
} \
lumiera_lock_section_.lock; \
}); \
({ \
LUMIERA_MUTEX_SECTION_UNLOCK; \
}))
/**
* Write locked section.
*/
#define LUMIERA_WRLOCK_SECTION(nobugflag, rwlck) \
for (lumiera_sectionlock NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) \
lumiera_lock_section_ = { \
rwlck, lumiera_rwlock_unlock_cb NOBUG_ALPHA_COMMA(&NOBUG_FLAG(nobugflag)) NOBUG_ALPHA_COMMA_NULL}; \
({ \
if (lumiera_lock_section_.lock) \
{ \
RESOURCE_WAIT (nobugflag, (rwlck)->rh, "acquire writelock", lumiera_lock_section_.rh); \
if (pthread_rwlock_wrlock (&(rwlck)->rwlock)) \
LUMIERA_DIE (LOCK_ACQUIRE); \
RESOURCE_STATE (nobugflag, NOBUG_RESOURCE_EXCLUSIVE, lumiera_lock_section_.rh); \
} \
lumiera_lock_section_.lock; \
}); \
({ \
LUMIERA_RWLOCK_SECTION_UNLOCK; \
}))
#define LUMIERA_WRLOCK_SECTION_CHAIN(nobugflag, rwlck) \
for (lumiera_sectionlock *lumiera_lock_section_old_ = &lumiera_lock_section_, \
NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) lumiera_lock_section_ = { \
rwlck, lumiera_rwlock_unlock_cb NOBUG_ALPHA_COMMA(&NOBUG_FLAG(nobugflag)) NOBUG_ALPHA_COMMA_NULL}; \
({ \
if (lumiera_lock_section_.lock) \
{ \
REQUIRE (lumiera_lock_section_old_->lock, "section prematurely unlocked"); \
RESOURCE_WAIT (nobugflag, (rwlck)->rh, "acquire writelock", lumiera_lock_section_.rh); \
if (pthread_rwlock_wrlock (&(twlck)->rwlock)) \
LUMIERA_DIE (LOCK_ACQUIRE); \
RESOURCE_STATE (nobugflag, NOBUG_RESOURCE_EXCLUSIVE, lumiera_lock_section_.rh); \
LUMIERA_SECTION_UNLOCK_(lumiera_lock_section_old_); \
} \
lumiera_lock_section_.lock; \
}); \
({ \
LUMIERA_MUTEX_SECTION_UNLOCK; \
}))
#define LUMIERA_RWLOCK_SECTION_UNLOCK \
LUMIERA_SECTION_UNLOCK_(&lumiera_lock_section_)
/**
* RWLock.
*
*/
struct lumiera_rwlock_struct
{
pthread_rwlock_t rwlock;
RESOURCE_HANDLE (rh);
};
typedef struct lumiera_rwlock_struct lumiera_rwlock;
typedef lumiera_rwlock* LumieraRWLock;
/**
* Initialize a rwlock
* @param self is a pointer to the rwlock to be initialized
* @return self as given
*/
LumieraRWLock
lumiera_rwlock_init (LumieraRWLock self, const char* purpose, struct nobug_flag* flag);
/**
* destroy a rwlock
* @param self is a pointer to the rwlock to be initialized
* @return self on success or NULL at error
*/
LumieraRWLock
lumiera_rwlock_destroy (LumieraRWLock self, struct nobug_flag* flag);
int
lumiera_rwlock_unlock_cb (void* rwlock);
#endif
/*
// Local Variables:
// mode: C
// c-file-style: "gnu"
// indent-tabs-mode: nil
// End:
*/