root.c

经典的psos编程实例源码

/* root.c */

#include "sys_conf.h"
#include <psos.h>
#include <prepc.h>
#include <stdio.h>

#include "misc.h"
#include "appl.h"

ULONG	qid1, qid2, qid3;
ULONG	tid;

void
drain(char * me, ULONG qid, char * qname)
{
	ULONG	rc;
	struct	message	in;
	char	str[256];
	int	some = FALSE;

	bprintf("Draining %s:", qname);
	do {	/* Drain Queue */
		rc = q_receive(qid, Q_NOWAIT, 0, (ULONG *) &in);
		if (rc == 0) {
			some = TRUE;
			str[0] = '\0';
			strncat(str, (char *) &(in.data), sizeof(in.data));
			bprintf(" %s", str);
		}
	} while (rc == 0);
	if (rc != ERR_NOMSG)
		fail(rc, "%s q_receive(%s)", me, qname);
	if (some)
		bprintf("\n");
	else
		bprintf(" EMPTY\n");
}

/* ROOT task */
void
root()
{
	void *dummy;
	ULONG ioretval, iopb[4], rc, args[4], other_tid, ignored, ev;
	char	* me = "ROOT";

	/* Initialize all drivers */
	de_init(DEV_TIMER, 0, &ioretval, &dummy);
	de_init(DEV_SERIAL, 0, &ioretval, &dummy);

	bpinit(128*100);
	bprintf("\nRoot task begin\n");

	/* Initialize the random number generator */
	srand(123456781L);

	/* Create the three queues */
	if (0 != (rc = q_create(Q1_NAM, 10, Q_LIMIT, & qid1)))
		fail(rc, "%s q_create(%s)", me, Q1_NAM);
	if (0 != (rc = q_create(Q2_NAM, 10, Q_LIMIT, & qid2)))
		fail(rc, "%s q_create(%s)", me, Q2_NAM);
	if (0 != (rc = q_create(Q3_NAM, 10, Q_LIMIT, & qid3)))
		fail(rc, "%s q_create(%s)", me, Q3_NAM);

	/* Store my Task ID */
	t_ident(0, 0, &tid);

	/* Create and start the other task */
	args[1] = args[2] = args[3] = 0;
	args[0] = (ULONG) T1_NAM;	/* His name */
	if (rc = t_create(T1_NAM, 128, 1024, 1024, 0, &other_tid))
		fail(rc, "root t_create(%s)", T1_NAM);
	if (rc = t_start(other_tid, 0, (void(*)()) tsk1, args))
		fail(rc, "root t_start(%s)", T1_NAM);

	/* Lower root's priority to be same as other task */
	t_setpri(0, 128, &ignored);

	/* Main loop */
	do {
		bprintf("%s looking for events\n", me);
		if (0 != (rc = ev_receive(SOMETHING,
				EV_WAIT | EV_ANY, 0, &ev)))
			fail(rc, "%s ev_receive()", me);
		bprintf("%s Events 0x%08x received\n", me, ev);
		if (ev & Q1_EV)
			drain(me, qid1, Q1_NAM);
		if (ev & Q2_EV)
			drain(me, qid2, Q2_NAM);
		if (ev & Q3_EV)
			drain(me, qid3, Q3_NAM);
	} while (!(ev & FINAL_EV));

	/* Clean up */
	if (0 != (rc = q_delete(qid1)))
		fail(rc, "%s q_delete(%s) failed", me, Q1_NAM);
	if (0 != (rc = q_delete(qid2)))
		fail(rc, "%s q_delete(%s) failed", me, Q2_NAM);
	if (0 != (rc = q_delete(qid3)))
		fail(rc, "%s q_delete(%s) failed", me, Q3_NAM);

	/* Example finished */
	bprintf("Root task end\n");
	bpflush();
	exit(0);
}