/* mutex.h - mutal exclusion locking Copyright (C) Lumiera.org 2008, Christian Thaeter 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_MUTEX_H #define LUMIERA_MUTEX_H #include "lib/error.h" #include "lib/sectionlock.h" #include #include /** * @file * Mutual exclusion locking, header. */ /** * Mutual exclusive section. */ #define LUMIERA_MUTEX_SECTION(nobugflag, mtx) \ for (lumiera_sectionlock NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) \ lumiera_lock_section_ = { \ (void*)1, lumiera_mutex_unlock_cb NOBUG_ALPHA_COMMA_NULL NOBUG_ALPHA_COMMA_NULL}; \ lumiera_lock_section_.lock;) \ for ( \ ({ \ lumiera_lock_section_.lock = (mtx); \ NOBUG_IF_ALPHA(lumiera_lock_section_.flag = &NOBUG_FLAG(nobugflag);) \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire mutex", &lumiera_lock_section_, \ NOBUG_RESOURCE_WAITING, lumiera_lock_section_.rh); \ if (pthread_mutex_lock (&(mtx)->mutex)) \ LUMIERA_DIE (LOCK_ACQUIRE); \ RESOURCE_STATE (nobugflag, NOBUG_RESOURCE_EXCLUSIVE, lumiera_lock_section_.rh); \ }); \ lumiera_lock_section_.lock; \ ({ \ LUMIERA_MUTEX_SECTION_UNLOCK; \ })) /** * Mutual exclusion chainbuilder section. * Usage: LUMIERA_MUTEX_SECTION(a){LUMIERA_MUTEX_SECTION_CHAIN(b){run();}} * calls lock(a); lock(b); unlock(a); run(); unlock(b); * This macro should only be used inside LUMIERA_MUTEX_SECTION and should be * called on the correct mutexes, period. */ #define LUMIERA_MUTEX_SECTION_CHAIN(nobugflag, mtx) \ for (lumiera_sectionlock *lumiera_lock_section_old_ = &lumiera_lock_section_, \ NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) lumiera_lock_section_ = { \ (void*)1, lumiera_mutex_unlock_cb NOBUG_ALPHA_COMMA_NULL NOBUG_ALPHA_COMMA_NULL}; \ lumiera_lock_section_.lock;) \ for ( \ ({ \ REQUIRE (lumiera_lock_section_old_->lock, "section prematurely unlocked"); \ lumiera_lock_section_.lock = mtx; \ NOBUG_IF_ALPHA(lumiera_lock_section_.flag = &NOBUG_FLAG(nobugflag);) \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire mutex", &lumiera_lock_section_, \ NOBUG_RESOURCE_WAITING, lumiera_lock_section_.rh); \ if (pthread_mutex_lock (&(mtx)->mutex)) \ 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_MUTEX_SECTION_UNLOCK \ LUMIERA_SECTION_UNLOCK_(&lumiera_lock_section_) /** * Recursive Mutual exclusive section. */ #define LUMIERA_RECMUTEX_SECTION(nobugflag, mtx) \ for (lumiera_sectionlock NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) \ lumiera_lock_section_ = { \ (void*)1, lumiera_mutex_unlock_cb NOBUG_ALPHA_COMMA_NULL NOBUG_ALPHA_COMMA_NULL}; \ lumiera_lock_section_.lock;) \ for ( \ ({ \ lumiera_lock_section_.lock = (mtx); \ NOBUG_IF_ALPHA(lumiera_lock_section_.flag = &NOBUG_FLAG(nobugflag);) \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire recmutex", &lumiera_lock_section_, \ NOBUG_RESOURCE_WAITING, lumiera_lock_section_.rh); \ if (pthread_mutex_lock (&(mtx)->recmutex)) \ LUMIERA_DIE (LOCK_ACQUIRE); \ RESOURCE_STATE (nobugflag, NOBUG_RESOURCE_RECURSIVE, lumiera_lock_section_.rh); \ }); \ lumiera_lock_section_.lock; \ ({ \ LUMIERA_MUTEX_SECTION_UNLOCK; \ })) #define LUMIERA_RECMUTEX_SECTION_CHAIN(nobugflag, mtx) \ for (lumiera_sectionlock *lumiera_lock_section_old_ = &lumiera_lock_section_, \ NOBUG_CLEANUP(lumiera_sectionlock_ensureunlocked) lumiera_lock_section_ = { \ (void*)1, lumiera_mutex_unlock_cb NOBUG_ALPHA_COMMA_NULL NOBUG_ALPHA_COMMA_NULL}; \ lumiera_lock_section_.lock;) \ for ( \ ({ \ REQUIRE (lumiera_lock_section_old_->lock, "section prematurely unlocked"); \ lumiera_lock_section_.lock = (mtx); \ NOBUG_IF_ALPHA(lumiera_lock_section_.flag = &NOBUG_FLAG(nobugflag);) \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire recmutex", &lumiera_lock_section_, \ NOBUG_RESOURCE_WAITING, lumiera_lock_section_.rh); \ if (pthread_mutex_lock (&(mtx)->recmutex)) \ LUMIERA_DIE (LOCK_ACQUIRE); \ RESOURCE_STATE (nobugflag, NOBUG_RESOURCE_RECURSIVE, lumiera_lock_section_.rh); \ LUMIERA_SECTION_UNLOCK_(lumiera_lock_section_old_) \ }); \ lumiera_lock_section_.lock; \ ({ \ LUMIERA_MUTEX_SECTION_UNLOCK; \ })) #define LUMIERA_RECMUTEX_SECTION_UNLOCK \ LUMIERA_SECTION_UNLOCK_(&lumiera_lock_section_) /** * Mutex. * */ struct lumiera_mutex_struct { pthread_mutex_t mutex; RESOURCE_HANDLE (rh); }; typedef struct lumiera_mutex_struct lumiera_mutex; typedef lumiera_mutex* LumieraMutex; struct lumiera_recmutex_struct { pthread_mutex_t recmutex; RESOURCE_HANDLE (rh); }; typedef struct lumiera_recmutex_struct lumiera_recmutex; typedef lumiera_recmutex* LumieraRecmutex; /** * Initialize a mutex variable * This initializes a 'fast' default mutex which must not be locked recursively from one thread. * @param self is a pointer to the mutex to be initialized * @return self as given */ LumieraMutex lumiera_mutex_init (LumieraMutex self, const char* purpose, struct nobug_flag* flag); /** * Destroy a mutex variable * @param self is a pointer to the mutex to be destroyed * @return self as given */ LumieraMutex lumiera_mutex_destroy (LumieraMutex self, struct nobug_flag* flag); /** * Initialize a recursive mutex variable * Initializes a 'recursive' mutex which might be locked by the same thread multiple times. * @param self is a pointer to the mutex to be initialized * @return self as given */ LumieraRecmutex lumiera_recmutex_init (LumieraRecmutex self, const char* purpose, struct nobug_flag* flag); /** * Destroy a recursive mutex variable * @param self is a pointer to the mutex to be destroyed * @return self as given */ LumieraRecmutex lumiera_recmutex_destroy (LumieraRecmutex self, struct nobug_flag* flag); /** * Callback for unlocking mutexes. * @internal */ int lumiera_mutex_unlock_cb (void* mutex); #endif /* // Local Variables: // mode: C // c-file-style: "gnu" // indent-tabs-mode: nil // End: */