#include <u.h>#include <libc.h>#include <fcall.h>#include <thread.h>#include <9p.h>#include "dat.h"  static longt(Ioproc *io, void (*op)(Ioproc*), int n, ...){	int i, ret;	va_list arg; 	assert(!io->inuse);	io->inuse = 1;	io->op = op;	va_start(arg, n);	for(i=0; i<n; i++)		io->arg[i] = va_arg(arg, long);	sendp(io->c, io);	recvp(io->c);	ret = io->ret;	if(ret < 0)		errstr(io->err, sizeof io->err);	io->inuse = 0;	return ret;} static voidt2(Ioproc *io, int ret){	io->ret = ret;	if(ret < 0)		rerrstr(io->err, sizeof io->err);	sendp(io->c, io);} static void ioread2(Ioproc*);static longioread(Ioproc *io, int fd, void *a, long n){	return t(io, ioread2, 3, fd, a, n);}static voidioread2(Ioproc *io){	t2(io, read(io->arg[0], (void*)io->arg[1], io->arg[2]));} static void iowrite2(Ioproc*);static longiowrite(Ioproc *io, int fd, void *a, long n){	return t(io, iowrite2, 3, fd, a, n);}static voidiowrite2(Ioproc *io){	t2(io, write(io->arg[0], (void*)io->arg[1], io->arg[2]));} static void ioclose2(Ioproc*);static intioclose(Ioproc *io, int fd){	return t(io, ioclose2, 1, fd);}static voidioclose2(Ioproc *io){	t2(io, close(io->arg[0]));} static voidiointerrupt(Ioproc *io){	if(!io->inuse)		return;	postnote(PNPROC, io->pid, "interrupt");} static intpipenote(void*, char *msg){	if(strstr(msg, "sys: write on closed pipe") || strstr(msg, "interrupt"))		return 1;	return 0;} static voidxioproc(void *a){	Ioproc *io; 	threadnotify(pipenote, 1);	io = a;	io->pid = getpid();	sendp(io->c, nil);	for(;;){		io = recvp(io->c);		if(io == nil)			continue;		io->op(io);	}	chanfree(io->c);	free(io);} Ioproc iofns ={	ioread,	iowrite,	ioclose,	iointerrupt,}; Ioproc *iofree; Ioproc*ioproc(void){	Ioproc *io; 	if((io = iofree) != nil){		iofree = io->next;		return io;	}	io = emalloc(sizeof(*io));	*io = iofns;	io->c = chancreate(sizeof(void*), 0);	if(proccreate(xioproc, io, STACK) < 0)		sysfatal("proccreate: %r");	recvp(io->c);	return io;} voidcloseioproc(Ioproc *io){	io->next = iofree;	iofree = io;}