tksem.c

T-kernel 的extension源代码

/*
 *----------------------------------------------------------------------
 *    T-Kernel / Standard Extension
 *
 *    Copyright (C) 2006 by Ken Sakamura. All rights reserved.
 *    T-Kernel / Standard Extension is distributed 
 *      under the T-License for T-Kernel / Standard Extension.
 *----------------------------------------------------------------------
 *
 *    Version:   1.00.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2006/8/11.
 *
 *----------------------------------------------------------------------
 */

/*
 *	tksem.c (taskcomm)
 *
 *	T-Kernel compatible semaphore
 */

#include "tcmgr.h"


/*
 * Generate semaphore
 *	T_CSEM
 *	exinf	Ignored
 *	sematr	TA_NODISWAI cannot be specified
 *		sematr:= (TA_TFIFO || TA_TPRI) |
 *		         (TA_FIRST || TA_CNT) | TA_DELEXIT
 */
EXPORT ID _tkse_cre_sem( T_CSEM *pk_csem )
{
	T_CSEM	csem;
	ID	id;
	ER	err;

	/* Parameter check */
	err = ChkSpaceR(pk_csem, sizeof(T_CSEM));
	if ( err < E_OK ) {
		goto err_ret1;
	}

	if ( (pk_csem->sematr & (TA_DSNAME | TA_NODISWAI) ) != 0U ) {
		err = E_RSATR;
		goto err_ret1;
	}

	csem = *pk_csem;
	if ( (pk_csem->sematr & (UW)TA_DELEXIT) != 0U ) {
		csem.exinf = GetTCinfo(TSK_SELF);
		csem.sematr &= ~(UW)TA_DELEXIT;
	} else {
		csem.exinf = NULL;
	}

	/* Generate semaphore */
	id = tk_cre_sem(&csem);
	if ( id < E_OK ) {
		err = id;
		goto err_ret1;
	}
	id = toBID(O_SEM, id);

	if (csem.exinf != NULL) {
		/* Register ID for deletion at termination. */
		err = tcmTkRegistObject(id);
		if ( err < E_OK ) {
			goto err_ret2;
		}
	}

	return id;

err_ret2:
	(void)tk_del_sem(toIID(id));
err_ret1:
	DEBUG_PRINT(("_tkse_cre_sem err = %d\n", err));
	return err;
}

/*
 * Delete semaphore
 *	When semaphore generation process terminates,
 *	the semaphore is deleted automatically.
 */
EXPORT ER _tkse_del_sem( ID id )
{
	TCINFO	*tcinfo;
	T_RSEM	rsem;
	ER	err;

	/* Check ID */
	err = tcmTkCheckID(O_SEM, id);
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Obtain semaphore information */
	err = tk_ref_sem(toIID(id), &rsem);
	if ( err < E_OK ) {
		goto err_ret;
	}

	tcinfo = rsem.exinf;  /* Generation process */

	/* Delete semaphore */
	err = tk_del_sem(toIID(id));
	if ( err < E_OK ) {
		goto err_ret;
	}

	if ( tcinfo != NULL ) {
		/* Deregister ID */
		err = tcmTkDeleteObject(id, tcinfo);
		if ( err < E_OK ) {
			goto err_ret;
		}
	}

	return E_OK;

err_ret:
	DEBUG_PRINT(("_tkse_del_sem err = %d\n", err));
	return err;
}

/*
 * Return resource to semaphore
 */
EXPORT ER _tkse_sig_sem( ID id, INT cnt )
{
	ER	err;

	/* Check ID */
	err = tcmTkCheckID(O_SEM, id);
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Return semaphore */
	err = tk_sig_sem(toIID(id), cnt);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return E_OK;

err_ret:
	DEBUG_PRINT(("_tkse_sig_sem err = %d\n", err));
	return err;
}

/*
 * Obtain resource from semaphore
 *	When interrupted by message handler,
 *	wait state is reset and E_DISWAI is returned.
 */
EXPORT ER _tkse_wai_sem( ID id, INT cnt, TMO tmout )
{
	ER	err;

	/* Check ID */
	err = tcmTkCheckID(O_SEM, id);
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Obtain semaphore */
	err = tk_wai_sem(toIID(id), cnt, tmout);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return E_OK;

err_ret:
	DEBUG_PRINT(("_tkse_wai_sem err = %d\n", err));
	return err;
}

/*
 * Refer to semaphore state
 *	T_RSEM
 *	exinf	Always return NULL
 */
EXPORT ER _tkse_ref_sem( ID id, T_RSEM *pk_rsem )
{
	T_RSEM	rsem;
	ER	err;

	/* Parameter check */
	err = ChkSpaceRW(pk_rsem, sizeof(T_RSEM));
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Check ID */
	err = tcmTkCheckID(O_SEM, id);
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Obtain semaphore information */
	err = tk_ref_sem(toIID(id), &rsem);
	if ( err < E_OK ) {
		goto err_ret;
	}

	*pk_rsem = rsem;
	pk_rsem->exinf = NULL;

	return E_OK;

err_ret:
	DEBUG_PRINT(("_tkse_ref_sem err = %d\n", err));
	return err;
}