9ae2b3a09d1e1d98617e4502c16f7af2f0f54742
10 int ret
= semget(IPC_PRIVATE
, 1, IPC_CREAT
| 0666);
11 return ret
< 0? -E_SEM_GET
: ret
;
14 int mutex_remove(int id
)
16 int ret
= semctl(id
, 0, IPC_RMID
);
17 return ret
< 0? -E_SEM_REMOVE
: 1;
20 static void para_semop(int id
, struct sembuf
*sops
, int num
)
22 if (semop(id
, sops
, num
) >= 0)
24 PARA_WARNING_LOG("semop failed (%s), retrying\n", strerror(errno
));
25 while (semop(id
, sops
, num
) < 0)
30 * lock the given mutex
32 * \sa semop(2), struct misc_meta_data
34 void mutex_lock(int id
)
36 struct sembuf sops
[2] = {
48 para_semop(id
, sops
, 2);
54 * \sa semop(2), struct misc_meta_data
56 void mutex_unlock(int id
)
58 struct sembuf sops
[1] = {
65 para_semop(id
, sops
, 1);
69 * create a new shared memory area of given size
73 int shm_new(size_t size
)
75 int ret
= shmget(IPC_PRIVATE
, size
, IPC_CREAT
| IPC_EXCL
| 0600);
76 return ret
< 0 ? -E_SHM_GET
: ret
;
80 * destroy the given shared memory area
83 int shm_destroy(int id
)
85 struct shmid_ds shm_desc
;
86 int ret
= shmctl(id
, IPC_RMID
, &shm_desc
);
87 return ret
< 0? -E_SHM_DESTROY
: ret
;
91 * attach a shared memory area
95 void *shm_attach(int id
, enum shm_attach_mode mode
)
97 if (mode
== ATTACH_RW
)
98 return shmat(id
, NULL
, 0);
99 return shmat(id
, NULL
, SHM_RDONLY
);
101 int shm_detach(void *addr
)
103 int ret
= shmdt(addr
);
104 return ret
< 0? -E_SHM_DETACH
: 1;