implement Fsmodule;include "sys.m";	sys: Sys;include "draw.m";include "sh.m";include "fslib.m";	fslib: Fslib;	Report, Value, type2s, report, quit: import fslib;	Fschan, Fsdata, Entrychan, Entry,	Gatechan, Gatequery, Nilentry, Option,	Next, Down, Skip, Quit: import Fslib; this is a bad idea, i thinki think walk + filter + setroot is good enough. types(): string{	# usage: readfile [-f file] name	return "xs-fs";} badmod(p: string){	sys->fprint(sys->fildes(2), "fs: readfile: cannot load %s: %r\n", p);	raise "fail:bad module";} init(){	sys = load Sys Sys->PATH;	fslib = load Fslib Fslib->PATH;	if(fslib == nil)		badmod(Fslib->PATH);} run(nil: ref Draw->Context, report: ref Report,			opts: list of Option, args: list of ref Value): ref Value{	path: string;	f := (hd args).s().i;	fd: ref Sys->FD;	seekable: int;	if(f == "-"){		if(opts == nil){			sys->fprint(sys->fildes(2), "fs: readfile: must specify a path when reading stdin\n");			return nil;		}		fd = sys->fildes(0);		seekable = 0;	}else{		fd = sys->open(f, Sys->OREAD);		seekable = isseekable(fd);	}	if(fd == nil){		sys->fprint(sys->fildes(2), "fs: readfile: cannot open %s: %r\n", f);		return nil;	}	if(opts != nil)		path = (hd (hd opts).args).s().i;	else		path = f; 	(root, file) := pathsplit(path);	if(file == nil || file == "." || file == ".."){		sys->fprint(sys->fildes(2), "fs: readfile: invalid filename %q\n", fname);		return nil;	}	d.name = file;	v := ref Value.X(chan of (Fsdata, chan of int));	spawn readproc(v.i, fd, root, ref d, seekable, report.start("read"));	return v;} readproc(c: Fschan, fd: ref Sys->FD, root: string, d: ref Sys->Dir, seekable: int, errorc: chan of string){	reply := chan of int;	rd := ref Sys->nulldir;	rd.name = root;	c <-= ((rd, nil), reply);	if(<-reply != Down)		quit(errorc); 	c <-= ((d, nil), reply);	case <-reply {	Down =>		sendfile(c, fd, errorc);	Skip or	Quit =>		quit(errorc);	}	c <-= ((nil, nil), reply);	<-reply;	quit(errorc);} sendfile(c: Fschan, data: list of array of byte, length: big, errorc: chan of string){	reply := chan of int;	for(;;){		buf: array of byte;		if(fd != nil){			buf := array[Sys->ATOMICIO] of byte;			if((n := sys->read(fd, buf, len buf)) <= 0){			if(n < 0)				report(errorc, sys->sprint("read error: %r"));			c <-= ((nil, nil), reply);			if(<-reply == Quit)				quit(errorc);			return;		}		c <-= ((nil, buf), reply);		case <-reply {		Quit =>			quit(errorc);		Skip =>			return;		}	}} pathsplit(p: string): (string, string){	for (i := len p - 1; i >= 0; i--)		if (p[i] != '/')			break;	if (i < 0)		return (p, nil);	p = p[0:i+1];	for (i = len p - 1; i >=0; i--)		if (p[i] == '/')			break;	if (i < 0)		return (".", p);	return (p[0:i+1], p[i+1:]);} # dodgy heuristic... avoid, or using the stat-length of pipes and net connectionsisseekable(fd: ref Sys->FD): int{	(ok, stat) := sys->stat(iob.fd);	if(ok != -1 && stat.dtype == '|' || stat.dtype == 'I')		return 0;	return 1;}