tkmtx.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.
 *
 *----------------------------------------------------------------------
 */

/*
 *	tkmtx.c (taskcomm)
 *
 *	T-Kernel compatible mutex
 */

#include "tcmgr.h"


/*
 * Generate mutex
 *	T_CMTX
 *	exinf	Ignored
 *	mtxatr	Priority inheritance and ceiling protocols cannot be used.
 *		TA_NODISWAI cannot be specified
 *		mtxatr := (TA_TFIFO || TA_TPRI) | TA_DELEXIT
 *	ceilpri	Not used
 */
EXPORT ID _tkse_cre_mtx( T_CMTX *pk_cmtx )
{
	T_CMTX	cmtx;
	ID	id;
	ER	err;

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

	if ( ((pk_cmtx->mtxatr & TA_CEILING) > TA_TPRI )
	  || ((pk_cmtx->mtxatr & (TA_DSNAME | TA_NODISWAI) ) != 0U )) {
		err = E_RSATR;
		goto err_ret1;
	}

	cmtx = *pk_cmtx;
	if ( (pk_cmtx->mtxatr & (UW)TA_DELEXIT) != 0U ) {
		cmtx.exinf = GetTCinfo(TSK_SELF);
		cmtx.mtxatr &= ~(UW)TA_DELEXIT;
	} else {
		cmtx.exinf = NULL;
	}

	id = tk_cre_mtx(&cmtx);
	if ( id < E_OK ) {
		err = id;
		goto err_ret1;
	}
	id = toBID(O_MTX, id);

	if (cmtx.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_mtx(toIID(id));
err_ret1:
	DEBUG_PRINT(("_tkse_cre_mtx err = %d\n", err));
	return err;
}

/*
 * Delete mutex
 *	When the mutex generation process terminates,
 *	the mutex is deleted automatically.
 */
EXPORT ER _tkse_del_mtx( ID id )
{
	TCINFO	*tcinfo;
	T_RMTX	rmtx;
	ER	err;

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

	/* Obtain mutex information. */
	err = tk_ref_mtx(toIID(id), &rmtx);
	if ( err < E_OK ) {
		goto err_ret;
	}

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

	/* Delete mutex */
	err = tk_del_mtx(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_mtx err = %d\n", err));
	return err;
}

/*
 * Obtain lock for mutex.
 *	When interrupted by message handler,
 *	wait state is reset and E_DISWAI is returned.
 */
EXPORT ER _tkse_loc_mtx( ID id, TMO tmout )
{
	ER	err;

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

	/* Obtain lock. */
	err = tk_loc_mtx(toIID(id), tmout);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return E_OK;

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

/*
 * Unlock mutex.
 */
EXPORT ER _tkse_unl_mtx( ID id )
{
	ER	err;

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

	/* Unlock */
	err = tk_unl_mtx(toIID(id));
	if ( err < E_OK ) {
		goto err_ret;
	}

	return E_OK;

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

/*
 * Refer to mutex state
 *	T_RMTX
 *	exinf	Always return NULL
 */
EXPORT ER _tkse_ref_mtx( ID id, T_RMTX *pk_rmtx )
{
	T_RMTX	rmtx;
	ER	err;

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

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

	/* Obtain mutex information. */
	err = tk_ref_mtx(toIID(id), &rmtx);
	if ( err < E_OK ) {
		goto err_ret;
	}

	*pk_rmtx = rmtx;
	pk_rmtx->exinf = NULL;

	return E_OK;

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