#include <u.h>
#include <libc.h>
#include <thread.h>
enum {
	STACK = 16*2048,
};

typedef struct State {
	int id;
	int fd, tobeclosed;
	Channel *c;
} State;

static void
subproc(void *arg)
{
	State *m;
	char buf[1024];
	int n;

	m = arg;
	print("subproc tid=%d tobeclosed=%d\n", threadid(), m->tobeclosed);
	sleep(15000);
//	print(" subproc tid=%d pid=%d\n", m->id, threadpid(m->id));
//	close(m->tobeclosed);
//	sleep(15000);

	print("subproc writing fd=%d n=%d\n", m->fd, n);
	n = write(m->fd, buf, 5);
	print("subproc written fd=%d n=%d\n", m->fd, n);
	while((n = read(m->fd, buf, sizeof(buf))) > 0)
		print("subproc fd=%d] read n=%d\n", m->fd, n);
	print("subproc eof fd=%d n=%d\n", m->fd, n);
	sleep(15000);
	sendul(m->c, 0);
	print("exiting subproc tid=%d pid=%d\n", m->id, threadpid(m->id));
	threadexits(nil);
}

static void
mainproc(void *arg)
{
	State *m;
	char buf[1024];
	int n;

	m = arg;
	print("mainproc tid=%d tobeclosed=%d\n", threadid(), m->tobeclosed);
	sleep(15000);
//	print(" mainproc tid=%d pid=%d\n", m->id, threadpid(m->id));
//	close(m->tobeclosed);
//	sleep(15000);

	print("mainproc writing fd=%d n=%d\n", m->fd, n);
	n = write(m->fd, buf, 7);
	print("mainproc written fd=%d n=%d\n", m->fd, n);

	while((n = read(m->fd, buf, sizeof(buf))) > 0)
		print("mainproc fd=%d n=%d\n", m->fd, n);
	print("mainproc  fd=%d eof n=%d\n", m->fd, n);
	sleep(15000);
	sendul(m->c, 0);
	print("exiting mainproc tid=%d pid=%d\n", m->id, threadpid(m->id));
	threadexits(nil);
}

void
threadmain(int argc, char *argv[])
{
	State mainState, *m;
	State subState, *s;
	char buf[256];
	int i, j, k, l, n, N, maineof, subeof, ret, hang;
	int p[2];
	Alt a[] = {
	/*	 c			v		op   */
		{nil ,	nil,	CHANRCV},
		{nil,	nil,	CHANRCV},
		{nil,			nil,	CHANEND},
	};

	hang = 0;		//change to 1 to hang
	N = 1;

	m = &mainState;
	s = &subState;
	print("threadmain tid=%d pid=%d\n", threadid(), threadpid(threadid()));
	memset(m, 0, sizeof(State));
	m->c = chancreate(sizeof(int), 0);
	a[0].c = m->c;
	s->c = chancreate(sizeof(int), 0);
	a[1].c = s->c;

	for (l=0; l < N; l++) {
		print("for %d\n", l);
		if (pipe(p) < 0) {
			fprint(2, "pipe failed: %r\n");
			threadexitsall("pipe failed");
		}
		m->fd = p[0];
		m->tobeclosed = p[1];
		s->fd = p[1];
		s->tobeclosed = p[0];
	
	
//		m->id = procrfork(mainproc, m, STACK, RFFDG);
		m->id = proccreate(mainproc, m, STACK);
		print("started mainproc tid=%d pid=%d\n", m->id, threadpid(m->id));

//		s->id = procrfork(subproc, s, STACK, RFFDG);
		s->id = proccreate(subproc, s, STACK);
		print("started subproc tid=%d pid=%d\n", m->id, threadpid(m->id));

		sleep(60000);
		print("manthread after sleep\n");

		i = 0;
		j = 1;
		print("threadmain closing %d\n", p[j]);
		close(p[j]);
		print("threadmain closed %d\n", p[j]);

		if (!hang) {
			print("threadmain writing zero to %d\n", p[i]);
			n = write(p[i], buf, 0);
			print("threadmain write %d returns %d\n", p[i], n);
			sleep(15000);
		}

		print("threadmain closing %d\n", p[i]);
		close(p[i]);
		print("threadmain closed %d\n", p[i]);
		sleep(15000);

		maineof = 0;
		subeof = 0;
		while(!maineof || !subeof) {
			print("threadmain while alt maineof=%d subeof=%d\n", maineof, subeof);
			switch(ret = alt(a)){
			case 0:
				print("main eof\n");
				maineof = 1;
				break;
			case 1:
				print("sub eof\n");
				subeof = 1;
				break;
			default:
				print("should not happen ret=%d\n", ret);
				sysfatal("should not happen");
			}
		}
		print("threadmain while alt done\n");
	
	//	print("threadmain threadint mainid\n");
	//	threadint(m->mainid);
	//	print("threadmain done threadint mainid\n");

	}
	print("threadmain exiting\n");

	threadexits(nil);
}