1 files changed, 124 insertions, 0 deletions
diff --git a/appl/demo/ns/ns.b b/appl/demo/ns/ns.b
new file mode 100644
index 00000000..266a07ff
--- /dev/null
+++ b/appl/demo/ns/ns.b
@@ -0,0 +1,124 @@
+implement Ns;
+
+#
+# Copyright © 2003 Vita Nuova Holdings Limited.  All rights reserved.
+#
+
+include "sys.m";
+	sys: Sys;
+include "draw.m";
+include "arg.m";
+include "sh.m";
+	sh: Sh;
+
+ns : list of string;
+
+Ns: module {
+	init: fn(nil: ref Draw->Context, argv: list of string);
+};
+
+init(nil: ref Draw->Context, argv: list of string)
+{
+	sys = load Sys Sys->PATH;
+	if (sys == nil)
+		badmod(Sys->PATH);
+	sh = load Sh Sh->PATH;
+	if (sh == nil)
+		badmod(Sh->PATH);
+	# sys->pctl(sys->FORKNS, nil);
+	sys->unmount(nil, "/n/remote");
+	arg := load Arg Arg->PATH;
+	if (arg == nil)
+		badmod(Arg->PATH);
+
+	arg->init(argv);
+	arg->setusage("ns [-v] [-r relpath] paths...");
+	verbose := 0;
+	relpath := "";
+	while ((opt := arg->opt()) != 0) {
+		case opt {
+		'v' =>
+			verbose = 1;
+		'r' =>
+			relpath = arg->earg();
+			if (relpath == nil)
+				arg->usage();
+			if (relpath[len relpath - 1] != '/')
+				relpath[len relpath] = '/';
+		* =>
+			arg->usage();
+		}
+	}
+
+	ns = arg->argv();
+	arg = nil;
+	if (ns == nil) {
+		sys->fprint(fdout(), "error no namespace selected\n");
+		exit;
+	}
+	spawn buildns(relpath, verbose);
+}
+
+fdout(): ref sys->FD
+{
+	return sys->fildes(1);
+}
+
+buildns(relpath: string, verbose: int)
+{
+	# sys->pctl(sys->FORKNS, nil);
+	if (sh->run(nil, "memfs"::"/n/remote"::nil) != nil) {
+		sys->fprint(fdout(), "error MemFS mount failed\n");
+		exit;
+	}
+	for (tmpl := ns; tmpl != nil; tmpl = tl tmpl) {
+		nspath := hd tmpl;
+		if (nspath[len nspath - 1] != '/')
+			nspath[len nspath] = '/';
+
+		bindpath := nspath;
+		if (bindpath[:len relpath] == relpath) {
+			bindpath = "/n/remote/"+bindpath[len relpath:];
+			if (createdir(bindpath) != -1) {
+				if (sys->bind(nspath, bindpath, sys->MBEFORE | sys->MCREATE) == -1) {
+					if (sys->bind(nspath, bindpath, sys->MBEFORE) == -1)
+						sys->fprint(fdout(), "error bind failed %s: %r\n",bindpath);
+					else if (verbose)
+						sys->fprint(fdout(), "data nspath %s\n", nspath);
+				}
+				else if (verbose)
+					sys->fprint(fdout(), "data nspath %s\n", nspath);
+			}
+			else
+				sys->fprint(fdout(), "error create failed %s\n",bindpath);
+		}
+	}
+	spawn exportns();
+}
+
+exportns()
+{
+	sys->export(sys->fildes(0), "/n/remote", sys->EXPWAIT);
+}
+
+createdir(path: string): int
+{
+	(nil, lst) := sys->tokenize(path, "/");
+	npath := "";
+	for (; lst != nil; lst = tl lst) {
+		(n, nil) := sys->stat(npath + "/" + hd lst);
+		if (n == -1) {
+			fd := sys->create(npath + "/" + hd lst, sys->OREAD, 8r777 | sys->DMDIR);
+			if (fd == nil)
+				return -1;
+		}
+		npath += "/" + hd lst;
+	}
+	return 0;
+}
+
+badmod(path: string)
+{
+	sys->fprint(fdout(), "error Ns: failed to load: %s\n",path);
+	exit;
+}