#include <u.h>#include <libc.h>#include <regexp.h>#include <thread.h>#include <fcall.h> int debug;int dfd;int srvfd;int netfd[2];int srv_to_net[2];int net_to_srv[2];char *srv;char	*addr;char *ns;int export; void	shuffle(void *arg);int	post(char *srv);void	remoteside(void*);int	call(char *rsys, char *ns, char *srv);void*	emalloc(int size);void	localside(void*); char *REXEXEC = "ssh";char *prog = "import"; enum{	Stack= 32*1024}; voidusage(void){	fprint(2, "usage: %s [-df] [-s service] [-n remote-ns] [-p remote-prog] remote-system\n", argv0);	threadexitsall("usage");} voidfatal(char *fmt, ...){	char buf[256];	va_list arg; 	va_start(arg, fmt);	vseprint(buf, buf+sizeof buf, fmt, arg);	va_end(arg); 	fprint(2, "%s: %s\n", argv0 ? argv0 : "<prog>", buf);	threadexitsall("fatal");} voidthreadmain(int argc, char *argv[]){	int dofork;	int rem;	void (*fn)(void*); 	dofork = 1;	rem = 0;	ns = nil;	srv = "plumb"; 	ARGBEGIN{	case 'd':		debug = 1;		break;	case 'f':		dofork = 0;		break;	case 'n':	/* name of remote namespace */		ns = EARGF(usage());		break;	case 'p':		prog = EARGF(usage());		break;	case 's':	/* name of service */		srv = EARGF(usage());		break;	case 'R':		rem = 1;		break;	case 'x':		export = 1;		break;	}ARGEND 	if(debug){		char *dbgfile; 		if(rem)			dbgfile = smprint("/tmp/%s.export.debug", getuser());		else			dbgfile = smprint("/tmp/%s.import.debug", getuser());		dfd = create(dbgfile, OWRITE, 0664);		free(dbgfile);		fmtinstall('F', fcallfmt);	} 		if(rem){		netfd[0] = 0;		netfd[1] = 1;			write(1, "OK", 2);	}else{		if(argc != 1)			usage();		addr = argv[0];		/* connect to remote service */		netfd[0] = netfd[1] = call(addr, ns, srv);	} 	fn = localside;	if(rem+export == 1)		fn = remoteside;		if(rem || !dofork)		fn(nil);	else		proccreate(fn, nil, Stack);}  voidlocalside(void *arg){	USED(arg); 	/* start a loal service */	srvfd = post(srv); 	/* threads to shuffle messages each way */	srv_to_net[0] = srvfd;	srv_to_net[1] = netfd[1];	proccreate(shuffle, srv_to_net, Stack);	net_to_srv[0] = netfd[0];	net_to_srv[1] = srvfd;	shuffle(net_to_srv);} /* post a local service */intpost(char *srv){	int p[2]; 	if(pipe(p) < 0)		fatal("can't create pipe: %r"); 	/* 0 will be server end, 1 will be client end */	if(post9pservice(p[1], "plumb", nil) < 0)		fatal("post9pservice plumb: %r");	close(p[1]); 	return p[0];} /* start a stub on the remote server */intcall(char *rsys, char *ns, char *srv){	int p[2];	int ac;	char *av[12];	char buf[2]; 	if(pipe(p) < 0)		fatal("can't create pipe: %r");	ac = 0;	av[ac++] = REXEXEC;	av[ac++] = rsys;	av[ac++] = prog;	if(debug)		av[ac++] = "-d";	av[ac++] = "-R";	if(ns != nil){		av[ac++] = "-n";		av[ac++] = ns;	}	av[ac++] = "-s";	av[ac++] = srv;	if(export)		av[ac++] = "-x";	av[ac] = 0; 	if(debug){		fprint(dfd, "execing ");		for(ac = 0; av[ac]; ac++)			fprint(dfd, " %s", av[ac]);		fprint(dfd, "\n");	} 	switch(fork()){	case -1:		fatal("%r");	case 0:		dup(p[1], 0);		dup(p[1], 1);		close(p[0]);		close(p[1]);		execvp(REXEXEC, av);		fatal("can't exec %s", REXEXEC);	default:		break;	}	close(p[1]); 	/* ignore crap that might come out of the .profile */	/* keep reading till we have an "OK" */	if(read(p[0], &buf[0], 1) != 1)		fatal("EOF");	for(;;){		if(read(p[0], &buf[1], 1) != 1)			fatal("EOF");		if(strncmp(buf, "OK", 2) == 0)			break;		buf[0] = buf[1];	}	if(debug)		fprint(dfd, "got OK\n"); 	return p[0];} enum{	BLEN=16*1024}; voidshuffle(void *arg){	int *fd;	char *buf, *tbuf;	int n;	Fcall *t; 	fd = (int*)arg;	buf = emalloc(BLEN+1);	t = nil;	tbuf = nil;	for(;;){		n = read9pmsg(fd[0], buf, BLEN);		if(n <= 0){			if(debug)				fprint(dfd, "%d->%d read returns %d: %r\n", fd[0], fd[1], n);			break;		}		if(debug){			if(t == nil)				t = emalloc(sizeof(Fcall));			if(tbuf == nil)				tbuf = emalloc(BLEN+1);			memmove(tbuf, buf, n);	/* because convM2S is destructive */			if(convM2S((uchar*)tbuf, n, t) != n)				fprint(dfd, "%d->%d convert error in convM2S", fd[0], fd[1]);			else				fprint(dfd, "%d->%d %F\n", fd[0], fd[1], t);		}		if(write(fd[1], buf, n) != n)			break;	}} voidremoteside(void *v){	int srv_to_net[2];	int net_to_srv[2];	char *addr;	int srvfd; 	if(ns == nil)		ns = getns(); 	addr = smprint("unix!%s/%s", ns, srv);	if(addr == nil)		fatal("%r");	if(debug)		fprint(dfd, "remoteside starting %s\n", addr); 	srvfd = dial(addr, 0, 0, 0);	if(srvfd < 0)		fatal("dial %s: %r", addr);	if(debug)		fprint(dfd, "remoteside dial %s succeeded\n", addr);	fcntl(srvfd, F_SETFL, FD_CLOEXEC); 	/* threads to shuffle messages each way */	srv_to_net[0] = srvfd;	srv_to_net[1] = netfd[1];	proccreate(shuffle, srv_to_net, Stack);	net_to_srv[0] = netfd[0];	net_to_srv[1] = srvfd;	shuffle(net_to_srv); 	threadexitsall(0);} void*emalloc(int size){	void *x; 	x = malloc(size);	if(x == nil)		fatal("allocation fails: %r");	return x;}