Styxservers: module{	PATH: con "/dis/lib/styxservers.dis"; 	Fid: adt {		fid:		int;		# client's fid		path:		big;		# file's 64-bit unique path		qtype:	int;		# file's qid type (eg, Sys->QTDIR if directory)		isopen:	int;		# non-zero if file is open		mode:	int;		# if open, the open mode		doffset:	(int, int);	# (internal) cache of directory offset		uname:	string;	# user name from original attach		param:	string;	# attach aname from original attach		data:		array of byte;	# application data 		clone:	fn(f: self ref Fid, nf: ref Fid): ref Fid;		open:	fn(f: self ref Fid, mode: int, qid: Sys->Qid);		walk:	fn(f: self ref Fid, qid: Sys->Qid);	}; 	Navigator: adt {		c:		chan of ref Navop;		reply:	chan of (ref Sys->Dir, string); 		new:		fn(c: chan of ref Navop): ref Navigator;		stat:		fn(t: self ref Navigator, q: big): (ref Sys->Dir, string);		walk:	fn(t: self ref Navigator, parentq: big, name: string): (ref Sys->Dir, string);		readdir:	fn(t: self ref Navigator, q: big, offset, count: int): array of ref Sys->Dir;	}; 	Navop: adt {		reply:	chan of (ref Sys->Dir, string);	# channel for reply		path:		big;		# file or directory path		pick {		Stat =>		Walk =>			name: string;		Readdir =>			offset:	int;	# index (origin 0) of first directory entry to return			count: 	int;	# number of directory entries requested		}	}; 	Styxserver: adt {		fd:		ref Sys->FD;		# file server end of connection		fids:		array of list of ref Fid;	# hash table of fids		fidlock:	chan of int;		t:		ref Navigator;	# name space navigator for this server		rootpath:	big;		# Qid.path of root of its name space		msize:	int;		# negotiated Styx message size		replychan:	chan of ref Styx->Rmsg; 		new:		fn(fd: ref Sys->FD, t: ref Navigator, rootpath: big): (chan of ref Styx->Tmsg, ref Styxserver);		reply:	fn(srv: self ref Styxserver, m: ref Styx->Rmsg): int;		replydirect:	fn(srv: self ref Styxserver, m: ref Styx->Rmsg): int; 		# protocol operations		attach:	fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Attach): ref Fid;		clunk:	fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Clunk): ref Fid;		walk:	fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Walk): ref Fid;		open:	fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Open): ref Fid;		read:		fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Read): ref Fid;		remove:	fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Remove): ref Fid;		stat:		fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Stat); 		default:	fn(srv: self ref Styxserver, gm: ref Styx->Tmsg); 		# check validity but don't reply		cancreate:	fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Create): (ref Fid, int, ref Sys->Dir, string);		canopen:		fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Open): (ref Fid, int, ref Sys->Dir, string);		canremove:	fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Remove): (ref Fid, big, string);		canread:		fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Read): (ref Fid, string);		canwrite:		fn(srv: self ref Styxserver, m: ref Styx->Tmsg.Write): (ref Fid, string); 		# fid management		getfid:	fn(srv: self ref Styxserver, fid: int): ref Fid;		newfid:	fn(srv: self ref Styxserver, fid: int): ref Fid;		delfid:	fn(srv: self ref Styxserver, c: ref Fid);		allfids:	fn(srv: self ref Styxserver): list of ref Fid; 		iounit:	fn(srv: self ref Styxserver): int;	}; 	init:		fn(styx: Styx);	traceset:	fn(on: int); 	readbytes: fn(m: ref Styx->Tmsg.Read, d: array of byte): ref Styx->Rmsg.Read;	readstr: fn(m: ref Styx->Tmsg.Read, s: string): ref Styx->Rmsg.Read; 	openok:	fn(uname: string, omode, perm: int, fuid, fgid: string): int;	openmode: fn(o: int): int;		Einuse:	con "fid already in use";	Ebadfid:	con "bad fid";	Eopen:	con "fid already opened";	Enotfound:	con "file does not exist";	Enotdir:	con "not a directory";	Eperm:	con "permission denied";	Ebadarg:	con "bad argument";	Eexists:	con "file already exists";	Emode:	con "open/create -- unknown mode";	Eoffset:	con "read/write -- bad offset";	Ecount:	con "read/write -- count negative or exceeds msgsize";	Enotopen: con "read/write -- on non open fid";	Eaccess:	con "read/write -- not open in suitable mode";	Ename:		con "bad character in file name";	Edot:		con ". and .. are illegal names";}; Nametree: module {	PATH: con "/dis/lib/nametree.dis";	Tree: adt {		c:		chan of ref Treeop;		reply:	chan of string; 		quit:		fn(t: self ref Tree);		create:	fn(t: self ref Tree, parent: big, d: Sys->Dir): string;		wstat:	fn(t: self ref Tree, path: big, d: Sys->Dir): string;		remove:	fn(t: self ref Tree, path: big): string;		getpath:	fn(t: self ref Tree, path: big): string;	};	Treeop: adt {		reply: chan of string;		q: big;		pick {		Create or		Wstat =>			d: Sys->Dir;		Remove =>		Getpath =>		}	};	init:		fn();	start:		fn(): (ref Tree, chan of ref Styxservers->Navop);};