#include <u.h>#include <libc.h>#include <thread.h>#include <fcall.h>#include <9p.h> static void_reqqueueproc(void *v){	Reqqueue *q;	Req *r;	void (*f)(Req *);	int fd;	char *buf; 	q = v;	rfork(RFNOTEG); 	buf = smprint("/proc/%lud/ctl", (ulong)getpid());	fd = open(buf, OWRITE|OCEXEC);	free(buf);		for(;;){		qlock(q);		q->flush = 0;		if(fd >= 0)			write(fd, "nointerrupt", 11);		q->cur = nil;		while(q->next == q)			rsleep(q);		r = (Req*)(((char*)q->next) - ((char*)&((Req*)0)->qu));		r->qu.next->prev = r->qu.prev;		r->qu.prev->next = r->qu.next;		f = r->qu.f;		memset(&r->qu, 0, sizeof(r->qu));		q->cur = r;		qunlock(q);		if(f == nil)			break;		f(r);	} 	if(fd >= 0)		close(fd);	free(r);	free(q);	threadexits(nil);} Reqqueue *reqqueuecreate(void){	Reqqueue *q; 	q = emalloc9p(sizeof(*q));	memset(q, 0, sizeof(*q));	q->l = q;	q->next = q->prev = q;	q->pid = proccreate(_reqqueueproc, q, mainstacksize);	return q;} voidreqqueuepush(Reqqueue *q, Req *r, void (*f)(Req *)){	qlock(q);	r->qu.f = f;	r->qu.next = q;	r->qu.prev = q->prev;	q->prev->next = &r->qu;	q->prev = &r->qu;	rwakeup(q);	qunlock(q);} voidreqqueueflush(Reqqueue *q, Req *r){	qlock(q);	if(q->cur == r){		threadint(q->pid);		q->flush++;		qunlock(q);	}else{		if(r->qu.next != nil){			r->qu.next->prev = r->qu.prev;			r->qu.prev->next = r->qu.next;		}		memset(&r->qu, 0, sizeof(r->qu));		qunlock(q);		respond(r, "interrupted");	}} voidreqqueuefree(Reqqueue *q){	Req *r; 	if(q == nil)		return;	r = emalloc9p(sizeof(Req));	reqqueuepush(q, r, nil);}