libmetal
mutex.h
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30 
31 /*
32  * @file generic/mutex.h
33  * @brief Generic mutex primitives for libmetal.
34  */
35 
36 #ifndef __METAL_MUTEX__H__
37 #error "Include metal/mutex.h instead of metal/generic/mutex.h"
38 #endif
39 
40 #ifndef __METAL_GENERIC_MUTEX__H__
41 #define __METAL_GENERIC_MUTEX__H__
42 
43 #include "metal/atomic.h"
44 
45 #ifdef __cplusplus
46 extern "C" {
47 #endif
48 
49 typedef struct {
52 
53 #define METAL_MUTEX_INIT { ATOMIC_VAR_INIT(0) }
54 
55 static inline void metal_mutex_init(metal_mutex_t *mutex)
56 {
57  atomic_store(&mutex->v, 0);
58 }
59 
60 static inline void metal_mutex_deinit(metal_mutex_t *mutex)
61 {
62  (void)mutex;
63 }
64 
65 static inline int metal_mutex_try_acquire(metal_mutex_t *mutex)
66 {
67  return 1 - atomic_flag_test_and_set(&mutex->v);
68 }
69 
70 static inline void metal_mutex_acquire(metal_mutex_t *mutex)
71 {
72  while (atomic_flag_test_and_set(&mutex->v)) {
73  ;
74  }
75 }
76 
77 static inline void metal_mutex_release(metal_mutex_t *mutex)
78 {
79  atomic_flag_clear(&mutex->v);
80 }
81 
82 static inline int metal_mutex_is_acquired(metal_mutex_t *mutex)
83 {
84  return atomic_load(&mutex->v);
85 }
86 
87 #ifdef __cplusplus
88 }
89 #endif
90 
91 #endif /* __METAL_GENERIC_MUTEX__H__ */
atomic_int v
Definition: mutex.h:50
static void metal_mutex_init(metal_mutex_t *mutex)
Definition: mutex.h:55
static int metal_mutex_is_acquired(metal_mutex_t *mutex)
Definition: mutex.h:82
static void metal_mutex_deinit(metal_mutex_t *mutex)
Definition: mutex.h:60
#define atomic_flag_test_and_set(FLAG)
Definition: atomic.h:67
static void metal_mutex_acquire(metal_mutex_t *mutex)
Definition: mutex.h:70
static int metal_mutex_try_acquire(metal_mutex_t *mutex)
Definition: mutex.h:65
#define atomic_flag_clear(FLAG)
Definition: atomic.h:71
#define atomic_store(OBJ, VAL)
Definition: atomic.h:79
#define atomic_load(OBJ)
Definition: atomic.h:83
Definition: mutex.h:52
static void metal_mutex_release(metal_mutex_t *mutex)
Definition: mutex.h:77
int atomic_int
Definition: atomic.h:48