1 files changed, 127 insertions, 0 deletions
diff --git a/appl/cmd/ip/virgild.b b/appl/cmd/ip/virgild.b
new file mode 100644
index 00000000..29ebba67
--- /dev/null
+++ b/appl/cmd/ip/virgild.b
@@ -0,0 +1,127 @@
+implement Virgild;
+
+include "sys.m";
+sys: Sys;
+
+include "draw.m";
+
+include "ip.m";
+
+Virgild: module
+{
+	init:	fn(ctxt: ref Draw->Context, argv: list of string);
+};
+
+stderr: ref Sys->FD;
+
+Udphdrsize: con IP->OUdphdrlen;
+
+init(nil: ref Draw->Context, nil: list of string)
+{
+	sys = load Sys Sys->PATH;
+
+	stderr = sys->fildes(2);
+
+	sys->pctl(Sys->FORKNS|Sys->FORKFD, nil);
+	if(sys->chdir("/lib/ndb") < 0){
+		sys->fprint(stderr, "virgild: no database\n");
+		return;
+	}
+
+	for(;;sys->sleep(10*1000)){
+		fd := openlisten();
+		if(fd == nil)
+			return;
+
+		buf := array[512] of byte;
+		for(;;){
+			n := sys->read(fd, buf, len buf);
+			if(n <= Udphdrsize){
+				break;
+			}
+			if(n <= Udphdrsize+1)
+				continue;
+
+			# dump any cruft after the question
+			for(i := Udphdrsize; i < n; i++){
+				c := int buf[i];
+				if(c == ' ' || c == 0 || c == '\n')
+					break;
+			}
+
+			answer := query(string buf[Udphdrsize:i]);
+			if(answer == nil)
+				continue;
+
+			# reply
+			r := array of byte answer;
+			if(len r > len buf - Udphdrsize)
+				continue;
+			buf[Udphdrsize:] = r;
+			sys->write(fd, buf, Udphdrsize+len r);
+		}
+		fd = nil;
+	}
+}
+
+openlisten(): ref Sys->FD
+{
+	(ok, c) := sys->announce("udp!*!virgil");
+	if(ok < 0){
+		sys->fprint(stderr, "virgild: can't open port: %r\n");
+		return nil;
+	}
+
+	if(sys->fprint(c.cfd, "headers") <= 0){
+		sys->fprint(stderr, "virgild: can't set headers: %r\n");
+		return nil;
+	}
+	sys->fprint(c.cfd, "oldheaders");
+
+	c.dfd = sys->open(c.dir+"/data", Sys->ORDWR);
+	if(c.dfd == nil) {
+		sys->fprint(stderr, "virgild: can't open data file\n");
+		return nil;
+	}
+	return c.dfd;
+}
+
+#
+#  query is userid?question
+#
+#  for now, we're ignoring userid
+#
+query(request: string): string
+{
+	(n, l) := sys->tokenize(request, "?");
+	if(n < 2){
+		sys->fprint(stderr, "virgild: bad request %s %d\n", request, n);
+		return nil;
+	}
+
+	#
+	#  until we have something better, ask cs
+	#  to translate, make the request look cs-like
+	#
+	fd := sys->open("/net/cs", Sys->ORDWR);
+	if(fd == nil){
+		sys->fprint(stderr, "virgild: can't open /net/cs - %r\n");
+		return nil;
+	}
+	q := array of byte ("tcp!" + hd(tl l) + "!1000");
+	if(sys->write(fd, q, len q) < 0){
+		sys->fprint(stderr, "virgild: can't write /net/cs - %r: %s\n", string q);
+		return nil;
+	}
+	sys->seek(fd, big 0, 0);
+	buf := array[512-Udphdrsize-len request-1] of byte;
+	n = sys->read(fd, buf, len buf);
+	if(n <= 0){
+		sys->fprint(stderr, "virgild: can't read /net/cs - %r\n");
+		return nil;
+	}
+
+	(nil, l) = sys->tokenize(string buf[0:n], " \t");
+	(nil, l) = sys->tokenize(hd(tl l), "!");
+	return request + "=" + hd l;
+}