evtmsg.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.
 *
 *----------------------------------------------------------------------
 */

/*
 *	evtmsg.c (event)
 *
 *	Event management
 *	Event message
 */

#include "evtmgr.h"
#include <extension/message.h>
#include <sys/pinfo.h>


/*
 * Event message
 */
typedef struct {
	W		type;	/* Message type (MS_SYS5) */
	W		size;	/* Message body size */
	EVENT		evt;	/* Event  */
	EmDevEvt	dev;	/* Event notification from devices */
} EvtMsg;

/*
 * Send the event message.
 *	Call the EmInfo with it locked.
 */
EXPORT ER emSendEvtMsg( EVENT *evt, EmDevEvt *dev, W devsz )
{
	EvtMsg		msg;
	W		t_mask = (W)toEvtMsk(evt->type);
	EvtMsgEntry	*p, *end = &emInfo.evtMsgEntry[emInfo.maxEvtMsg];
	ER		err, error = E_OK;

	if ( (t_mask & emInfo.evtMsgMask) == 0 ) {
			return E_OK;  /* No event message request */
	}

	/* Outgoing message */
	msg.type = MS_SYS5;
	msg.size = (W)sizeof(EVENT) + devsz;
	msg.evt  = *evt;
	if ( devsz > 0 ) {
		memcpy(&msg.dev, dev, (size_t)devsz);
	}

	/* Find a registered request. */
	for ( p = emInfo.evtMsgEntry; p < end; ++p ) {

		if ( (p->t_mask & t_mask) == 0 ) {
			continue;
		}

		/* Send the event message. */
		err = tkse_snd_msg(p->req_pid, (MESSAGE*)&msg, NOWAIT);
		if ( err < E_OK ) {
			error = err;
		}
	}

DO_DEBUG(
	if ( error < E_OK ) {
		DEBUG_PRINT(("emSendEvtMsg err = %d\n", error));
	}
)
	return error;
}

/*
 * Register in the request list.
 */
EXPORT ER emRegistEvtMsg( W t_mask, W pid )
{
	EvtMsgEntry	*end = &emInfo.evtMsgEntry[emInfo.maxEvtMsg];
	EvtMsgEntry	*p, *free, *reg;
	W		mask;
	ER		err;

	Enter;

	/* Retrieve the registration position. */
	free = reg = NULL;
	mask = EM_NULL;
	for ( p = emInfo.evtMsgEntry; p < end; ++p ) {

		if ( p->t_mask == EM_NULL ) {
			free = p;		/* Free entry */
		} else {
			if ( p->req_pid == pid ) {
				reg = p;	/* Registered entry */
			} else {
				mask |= p->t_mask;
			}
		}
	}

	if ( reg != NULL ) {
		/* Reregistration/deregistration */
		reg->t_mask = t_mask;
	} else {
		if ( t_mask != EM_NULL ) {
			if ( free == NULL ) {
				err = E_LIMIT;
				goto err_ret;
			}
			/* New registration */
			free->t_mask = t_mask;
			free->req_pid = pid;
		}
	}

	/* Update the request event mask */
	emInfo.evtMsgMask = mask | t_mask;

	Return (E_OK);

err_ret:
	DEBUG_PRINT(("registEvtMsg err = %d\n", err));
	Return (err);
}

/*
 * Register the event message request.
 */
EXPORT ER _tkse_req_evt( W t_mask )
{
	PINFO	*pinfo;
	ER	err;

	/* Parameter check */
	if ( t_mask < 0 ) {
		err = E_PAR;
		goto err_ret;
	}

	pinfo = GetPinfo(TSK_SELF);
	if ( pinfo == NULL ) {
		err = E_CTX;
		goto err_ret;
	}

	/* Registration */
	err = emRegistEvtMsg(t_mask, pinfo->procid);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return E_OK;

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