/* ** Copyright 2001-2002, Travis Geiselbrecht. All rights reserved. ** Distributed under the terms of the NewOS License. */ #ifndef _KERNEL_LOCK_H #define _KERNEL_LOCK_H #include <OS.h> #include <kernel.h> #include <debug.h> typedef struct recursive_lock { sem_id sem; thread_id holder; int recursion; } recursive_lock; #define ASSERT_LOCKED_RECURSIVE(r) { ASSERT(thread_get_current_thread_id() == (r)->holder); } typedef struct mutex { sem_id sem; thread_id holder; } mutex; #define ASSERT_LOCKED_MUTEX(m) { ASSERT(thread_get_current_thread_id() == (m)->holder); } typedef struct benaphore { sem_id sem; int32 count; } benaphore; // Note: this is currently a trivial r/w lock implementation // it will be replaced with something better later - this // or a similar API will be made publically available at this point. typedef struct rw_lock { sem_id sem; int32 count; benaphore writeLock; } rw_lock; #define RW_MAX_READERS 1000000 #ifdef __cplusplus extern "C" { #endif extern status_t recursive_lock_init(recursive_lock *lock, const char *name); extern void recursive_lock_destroy(recursive_lock *lock); extern bool recursive_lock_lock(recursive_lock *lock); extern bool recursive_lock_unlock(recursive_lock *lock); extern int recursive_lock_get_recursion(recursive_lock *lock); extern status_t mutex_init(mutex *m, const char *name); extern void mutex_destroy(mutex *m); extern void mutex_lock(mutex *m); extern void mutex_unlock(mutex *m); extern status_t benaphore_init(benaphore *ben, const char *name); extern void benaphore_destroy(benaphore *ben); static inline status_t benaphore_lock_etc(benaphore *ben, uint32 flags, bigtime_t timeout) { if (atomic_add(&ben->count, -1) <= 0) return acquire_sem_etc(ben->sem, 1, flags, timeout); return B_OK; } static inline status_t benaphore_lock(benaphore *ben) { if (atomic_add(&ben->count, -1) <= 0) return acquire_sem(ben->sem); return B_OK; } static inline status_t benaphore_unlock(benaphore *ben) { if (atomic_add(&ben->count, 1) < 0) return release_sem(ben->sem); return B_OK; } extern status_t rw_lock_init(rw_lock *lock, const char *name); extern void rw_lock_destroy(rw_lock *lock); extern status_t rw_lock_read_lock(rw_lock *lock); extern status_t rw_lock_read_unlock(rw_lock *lock); extern status_t rw_lock_write_lock(rw_lock *lock); extern status_t rw_lock_write_unlock(rw_lock *lock); #ifdef __cplusplus } #endif #endif /* _KERNEL_LOCK_H */