cre_sem

acre_sem

Outline

Create semaphore.

C format

 ER      cre_sem (ID semid, T_CSEM *pk_csem );

 ER_ID   acre_sem ( T_CSEM *pk_csem );

Parameter(s)

I/O	Parameter	Description
I	ID semid;	ID number of the semaphore.
I	T_CSEM *pk_csem;	Pointer to the packet containing the semaphore creation information.

[Semaphore creation information packet : T_CSEM]

typedef struct t_csem { ATR sematr; /*Semaphore attribute*/ UINT isemcnt; /*Initial semaphore count*/ UINT maxsem; /*Maximum semaphore count*/ } T_CSEM;

Explanation

This service call can be called from tasks that belong to Trusted Domain.

The cre_sem creates a semaphore with semaphore ID indicated by semid according to the content of pk_csem. The acre_sem creates a semaphore according to the content of pk_csem, and returns the created semaphore ID.

1 ) Semaphore attribute (sematr)
The following are specified for sematr.

   sematr := ( TA_TFIFO | TA_TPRI )

- TA_TFIFO ( = 0x0000)
Task wait queue is managed in FIFO order.

- TA_TPRI ( = 0x0001)
Task wait queue is managed in task current priority order. Among tasks with the same priority, they are queued in FIFO order.

2 ) Initial semaphore count (isemcnt)
Specify initial semaphore count within the range from 0 to maxsem.

3 ) Maximum semaphore count (maxsem)
Specify maximum semaphore count within the range from 1 to TMAX_MAXSEM ( = 65535).

Return value

Macro	Value	Description
-	Positive value	Normal completion of acre_sem. (Created semaphore ID)
E_OK	0	Normal completion of cre_sem.
E_RSATR	-11	Reserved attribute - Either of bits in sematr except bit0 is 1.
E_PAR	-17	Parameter error. - pk_csem == NULL - maxsem == 0 - maxsem > TMAX_MAXSEM - maxsem < isemcnt
E_ID	-18	Invalid ID number. (only for cre_sem) - semid < 0 - semid > VTMAX_SEM
E_CTX	-25	Context error. - This service call was issued in the CPU locked state. - This service call was issued from non-task. - This service call was issued in the status "PSW.IPL > kernel interrupt mask level".
E_MACV	-26	Memory access violation. - Stack pointer points out of user stack for invoking task. - The operand-read access to the area indicated by pk_csem has not been permitted to the invoking task.
E_OACV	-27	Object access violation. - The invoking task does not belong to trusted domain.
E_NOID	-34	No ID number available.(only for acre_sem)
E_OBJ	-41	Object state error. (only for cre_sem) - The semaphore specified by semid exists.