/* 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 #include /** * @file * Mutual exclusion locking, header. */ LUMIERA_ERROR_DECLARE (MUTEX_LOCK); LUMIERA_ERROR_DECLARE (MUTEX_UNLOCK); LUMIERA_ERROR_DECLARE (MUTEX_DESTROY); /** * Mutual exclusive section. */ #define LUMIERA_MUTEX_SECTION(nobugflag, mtx) \ for (lumiera_mutexacquirer NOBUG_CLEANUP(lumiera_mutexacquirer_ensureunlocked) lumiera_mutex_section_ \ = {(LumieraMutex)1 NOBUG_ALPHA_COMMA_NULL}; \ lumiera_mutex_section_.mutex;) \ for ( \ ({ \ lumiera_mutex_section_.mutex = (mtx); \ NOBUG_RESOURCE_HANDLE_INIT (lumiera_mutex_section_.rh); \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire mutex", &lumiera_mutex_section_, \ NOBUG_RESOURCE_EXCLUSIVE, lumiera_mutex_section_.rh); \ if (pthread_mutex_lock (&(mtx)->mutex)) LUMIERA_DIE (MUTEX_LOCK); \ }); \ lumiera_mutex_section_.mutex; \ ({ \ if (lumiera_mutex_section_.mutex) \ { \ pthread_mutex_unlock (&lumiera_mutex_section_.mutex->mutex); \ lumiera_mutex_section_.mutex = NULL; \ RESOURCE_LEAVE(nobugflag, lumiera_mutex_section_.rh); \ } \ })) /** * 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_mutexacquirer *lumiera_mutex_section_old_ = &lumiera_mutex_section_, \ NOBUG_CLEANUP(lumiera_mutexacquirer_ensureunlocked) lumiera_mutex_section_ = {(LumieraMutex)1 \ NOBUG_ALPHA_COMMA_NULL}; \ lumiera_mutex_section_.mutex;) \ for ( \ ({ \ lumiera_mutex_section_.mutex = (mtx); \ NOBUG_RESOURCE_HANDLE_INIT (lumiera_mutex_section_.rh); \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire mutex", &lumiera_mutex_section_, \ NOBUG_RESOURCE_EXCLUSIVE, lumiera_mutex_section_.rh); \ if (pthread_mutex_lock (&(mtx)->mutex)) LUMIERA_DIE (MUTEX_LOCK); \ if (lumiera_mutex_section_old_->mutex) \ { \ pthread_mutex_unlock (&lumiera_mutex_section_old_->mutex->mutex); \ lumiera_mutex_section_old_->mutex = NULL; \ RESOURCE_LEAVE(nobugflag, lumiera_mutex_section_old_->rh); \ } \ }); \ lumiera_mutex_section_.mutex; \ ({ \ if (lumiera_mutex_section_.mutex) \ { \ pthread_mutex_unlock (&lumiera_mutex_section_.mutex->mutex); \ lumiera_mutex_section_.mutex = NULL; \ RESOURCE_LEAVE(nobugflag, lumiera_mutex_section_.rh); \ } \ })) /** * Recursive Mutual exclusive section. */ #define LUMIERA_RECMUTEX_SECTION(nobugflag, mtx) \ for (lumiera_mutexacquirer NOBUG_CLEANUP(lumiera_mutexacquirer_ensureunlocked) lumiera_mutex_section_ \ = {(LumieraMutex)1 NOBUG_ALPHA_COMMA_NULL}; \ lumiera_mutex_section_.mutex;) \ for ( \ ({ \ lumiera_mutex_section_.mutex = (mtx); \ NOBUG_RESOURCE_HANDLE_INIT (lumiera_mutex_section_.rh); \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire recmutex", &lumiera_mutex_section_, \ NOBUG_RESOURCE_RECURSIVE, lumiera_mutex_section_.rh); \ if (pthread_mutex_lock (&(mtx)->mutex)) LUMIERA_DIE (MUTEX_LOCK); \ }); \ lumiera_mutex_section_.mutex; \ ({ \ if (lumiera_mutex_section_.mutex) \ { \ pthread_mutex_unlock (&lumiera_mutex_section_.mutex->mutex); \ lumiera_mutex_section_.mutex = NULL; \ RESOURCE_LEAVE(nobugflag, lumiera_mutex_section_.rh); \ } \ })) /** * Mutual exclusion chainbuilder section. * Usage: LUMIERA_MUTEX_SECTION(a){LUMIERA_RECMUTEX_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_RECMUTEX_SECTION_CHAIN(nobugflag, mtx) \ for (lumiera_mutexacquirer *lumiera_mutex_section_old_ = &lumiera_mutex_section_, \ NOBUG_CLEANUP(lumiera_mutexacquirer_ensureunlocked) lumiera_mutex_section_ = {(LumieraMutex)1 \ NOBUG_ALPHA_COMMA_NULL}; \ lumiera_mutex_section_.mutex;) \ for ( \ ({ \ lumiera_mutex_section_.mutex = (mtx); \ NOBUG_RESOURCE_HANDLE_INIT (lumiera_mutex_section_.rh); \ RESOURCE_ENTER (nobugflag, (mtx)->rh, "acquire recmutex", &lumiera_mutex_section_, \ NOBUG_RESOURCE_RECURSIVE, lumiera_mutex_section_.rh); \ if (pthread_mutex_lock (&(mtx)->mutex)) LUMIERA_DIE (MUTEX_LOCK); \ if (lumiera_mutex_section_old_->mutex) \ { \ pthread_mutex_unlock (&lumiera_mutex_section_old_->mutex->mutex); \ lumiera_mutex_section_old_->mutex = NULL; \ RESOURCE_LEAVE(nobugflag, lumiera_mutex_section_old_->rh); \ } \ }); \ lumiera_mutex_section_.mutex; \ ({ \ if (lumiera_mutex_section_.mutex) \ { \ pthread_mutex_unlock (&lumiera_mutex_section_.mutex->mutex); \ lumiera_mutex_section_.mutex = NULL; \ RESOURCE_LEAVE(nobugflag, lumiera_mutex_section_.rh); \ } \ })) /** * Mutex. * */ struct lumiera_mutex_struct { pthread_mutex_t mutex; RESOURCE_HANDLE (rh); }; typedef struct lumiera_mutex_struct lumiera_mutex; typedef lumiera_mutex* LumieraMutex; /** * 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); /** * Initialize a 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 */ LumieraMutex lumiera_recmutex_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); /** * mutexacquirer used to manage the state of a mutex. */ struct lumiera_mutexacquirer_struct { LumieraMutex mutex; RESOURCE_HANDLE (rh); }; typedef struct lumiera_mutexacquirer_struct lumiera_mutexacquirer; typedef struct lumiera_mutexacquirer_struct* LumieraMutexacquirer; /* helper function for nobug */ static inline void lumiera_mutexacquirer_ensureunlocked (LumieraMutexacquirer self) { ENSURE (!self->mutex, "forgot to unlock mutex"); } #endif /* // Local Variables: // mode: C // c-file-style: "gnu" // indent-tabs-mode: nil // End: */