implement Register; ## Copyright © 2003 Vita Nuova Holdings Limited.  All rights reserved.#  include "sys.m";	sys: Sys;include "draw.m";include "sh.m";include "registries.m";	registries: Registries;	Registry, Attributes, Service: import registries;include "grid/announce.m";	announce: Announce;include "arg.m"; registered: ref Registries->Registered; Register: module {	init: fn(ctxt: ref Draw->Context, argv: list of string);}; init(ctxt: ref Draw->Context, argv: list of string){	sys = load Sys Sys->PATH;	sys->pctl(sys->FORKNS | sys->NEWPGRP, nil);	registries = load Registries Registries->PATH;	if (registries == nil)		badmod(Registries->PATH);	registries->init();	announce = load Announce Announce->PATH;	if (announce == nil)		badmod(Announce->PATH);	announce->init();	arg := load Arg Arg->PATH;	if (arg == nil)		badmod(Arg->PATH); 	attrs := Attributes.new(("proto", "styx") :: ("auth", "none") :: ("resource","Cpu Pool") :: nil);	maxusers := -1;	autoexit := 0;	myaddr := "";	arg->init(argv);	arg->setusage("register [-u maxusers] [-e exit threshold] [-a attributes] { program }");	while ((opt := arg->opt()) != 0) {		case opt {		'm' =>			attrs.set("memory", memory());		'u' =>			if ((maxusers = int arg->earg()) <= 0)				arg->usage();		'e' =>			if ((autoexit = int arg->earg()) < 0)				arg->usage();		'A' =>			myaddr = arg->earg();		'a' =>			attr := arg->earg();			val := arg->earg();			attrs.set(attr, val);		}	}	argv = arg->argv();	if (argv == nil)		arg->usage();	(nil, plist) := sys->tokenize(hd argv, "{} \t\n");	arg = nil;		sysname := readfile("/dev/sysname");	reg: ref Registry;	reg = Registry.new("/mnt/registry");	if (reg == nil)		reg = Registry.connect(nil, nil, nil);	if (reg == nil)		error(sys->sprint("Could not find registry: %r\nMake sure that ndb/cs has been started and there is a registry announcing on the machine specified in /lib/ndb/local")); 	c : sys->Connection;	if (myaddr == nil) {		(addr, conn) := announce->announce();		if (addr == nil)			error(sys->sprint("cannot announce: %r"));		myaddr = addr;		c = *conn;	}	else {		n: int;		(n, c) = sys->announce(myaddr);		if (n == -1)			error(sys->sprint("cannot announce: %r"));		(n, nil) = sys->tokenize(myaddr, "*");		if (n > 1) {			(nil, lst) := sys->tokenize(myaddr, "!");			if (len lst >= 3)				myaddr = "tcp!" + sysname +"!" + hd tl tl lst;		}	}	persist := 0;	if (attrs.get("name") == nil)		attrs.set("name", sysname);	err: string;	(registered, err) = reg.register(myaddr, attrs, persist);	if (err != nil) 		error("could not register with registry: "+err); 	mountfd := popen(ctxt, plist);	spawn listener(c, mountfd, maxusers);} listener(c: Sys->Connection, mountfd: ref sys->FD, maxusers: int){	for (;;) {		(n, nc) := sys->listen(c);		if (n == -1)			error(sys->sprint("listen failed: %r"));		dfd := sys->open(nc.dir + "/data", Sys->ORDWR);		if (maxusers != -1 && nusers >= maxusers)			sys->fprint(stderr(), "register: maxusers (%d) exceeded!\n", nusers);		else if (dfd != nil) {			sync := chan of int;			addr := readfile(nc.dir + "/remote");			if (addr == nil)				addr = "unknown";			if (addr[len addr - 1] == '\n')				addr = addr[:len addr - 1];			spawn proxy(sync, dfd, mountfd, addr);			<-sync;		}	}} proxy(sync: chan of int, dfd, mountfd: ref sys->FD, addr: string){	pid := sys->pctl(Sys->NEWFD | Sys->NEWNS, 1 :: 2 :: mountfd.fd :: dfd.fd :: nil);	dfd = sys->fildes(dfd.fd);	mountfd = sys->fildes(mountfd.fd);	sync <-= 1;	done := chan of int;	spawn exportit(dfd, done);	if (sys->mount(mountfd, nil, "/", sys->MREPL | sys->MCREATE, addr) == -1)		sys->fprint(stderr(), "register: proxy mount failed: %r\n");	nusers++;	<-done;	nusers--;} nusers := 0;clock(tick: chan of int){	for (;;) {		sys->sleep(2000);		tick <-= 1;	}} exportit(dfd: ref sys->FD, done: chan of int){	sys->export(dfd, "/", sys->EXPWAIT);	done <-= 1;} popen(ctxt: ref Draw->Context, argv: list of string): ref Sys->FD{	sync := chan of int;	fds := array[2] of ref Sys->FD;	sys->pipe(fds);	spawn runcmd(ctxt, argv, fds[0], sync);	<-sync;	return fds[1];} runcmd(ctxt: ref Draw->Context, argv: list of string, stdin: ref Sys->FD, sync: chan of int){	pid := sys->pctl(Sys->FORKFD, nil);	sys->dup(stdin.fd, 0);	stdin = nil;	sync <-= 0;	sh := load Sh Sh->PATH;	sh->run(ctxt, argv);} error(e: string){	sys->fprint(stderr(), "register: %s\n", e);	raise "fail:error";} user(): string{	if ((s := readfile("/dev/user")) == nil)		return "none";	return s;} readfile(f: string): string{	fd := sys->open(f, sys->OREAD);	if(fd == nil)		return nil; 	buf := array[8192] of byte;	n := sys->read(fd, buf, len buf);	if(n < 0)		return nil; 	return string buf[0:n];	} stderr(): ref Sys->FD{	return sys->fildes(2);} badmod(path: string){	sys->fprint(stderr(), "Register: cannot load %s: %r\n", path);	exit;} killg(pid: int){	if ((fd := sys->open("/prog/" + string pid + "/ctl", Sys->OWRITE)) != nil) {		sys->fprint(fd, "killgrp");		fd = nil;	}} memory(): string{	buf := array[1024] of byte;	s := readfile("/dev/memory");	(nil, lst) := sys->tokenize(s, " \t\n");	if (len lst > 2) {		mem := int hd tl lst;		mem /= (1024*1024);		return string mem + "mb";	}	return "not known";}