hare

commit 7ce2904d1ff1f84462dd4622f8f3fc8d1d28ae03
parent 53081a0b2e5c289a425f8728f86c3de9c606d22d
Author: Armin Preiml <apreiml@strohwolke.at>
Date:   Tue, 23 May 2023 16:20:12 +0200

io::teestream: implement writer

Signed-off-by: Armin Preiml <apreiml@strohwolke.at>

Diffstat:
M
io/tee.ha
 | 
24
+++++++++++++++++-------

1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/io/tee.ha b/io/tee.ha
@@ -4,22 +4,23 @@
 
 export type teestream = struct {
 	vtable: stream,
-	source: handle,
+	h: handle,
 	sink: handle,
 };
 
 const tee_vtable: vtable = vtable {
 	reader = &tee_read,
+	writer = &tee_write,
 	...
 };
 
-// Creates a reader which copies reads into a sink before forwarding them to the
-// caller. This stream does not need to be closed, and closing it will not close
-// the secondary streams.
-export fn tee(source: handle, sink: handle) teestream = {
+// Creates a stream which copies writes and reads into 'sink' after forwarding
+// them to the handle 'h'. This stream does not need to be closed, and closing
+// it will not close the secondary stream.
+export fn tee(h: handle, sink: handle) teestream = {
 	return teestream {
 		vtable = &tee_vtable,
-		source = source,
+		h = h,
 		sink = sink,
 		...
 	};
@@ -27,7 +28,7 @@ export fn tee(source: handle, sink: handle) teestream = {
 
 fn tee_read(s: *stream, buf: []u8) (size | EOF | error) = {
 	let s = s: *teestream;
-	let z = match (read(s.source, buf)?) {
+	let z = match (read(s.h, buf)?) {
 	case EOF =>
 		return EOF;
 	case let z: size =>
@@ -38,3 +39,12 @@ fn tee_read(s: *stream, buf: []u8) (size | EOF | error) = {
 	};
 	return z;
 };
+
+fn tee_write(s: *stream, buf: const []u8) (size | error) = {
+	let s = s: *teestream;
+	const z = write(s.h, buf)?;
+	for (let n = 0z; n < z) {
+		n += write(s.sink, buf[n..z])?;
+	};
+	return z;
+};