From: Matt Joiner <anacrolix@gmail.com>
Date: Tue, 5 Aug 2025 14:00:32 +0000 (+1000)
Subject: Try to show context cancellation cause after io.ReadFull
X-Git-Tag: v1.59.0~2^2~45
X-Git-Url: http://www.git.stargrave.org/?a=commitdiff_plain;h=23f52690acff5b6fe540603984db95eac2564097;p=btrtrc.git

Try to show context cancellation cause after io.ReadFull
---

diff --git a/webseed-peer.go b/webseed-peer.go
index 5dcef078..b1ff7dd4 100644
--- a/webseed-peer.go
+++ b/webseed-peer.go
@@ -288,6 +288,10 @@ func (ws *webseedPeer) readChunks(wr *webseedRequest) (err error) {
 		var n int
 		n, err = io.ReadFull(wr.request.Body, buf)
 		ws.peer.readBytes(int64(n))
+		reqCtxErr := context.Cause(wr.request.Context())
+		if errors.Is(err, reqCtxErr) {
+			err = reqCtxErr
+		}
 		if webseed.PrintDebug && wr.cancelled.Load() {
 			fmt.Printf("webseed read %v after cancellation: %v\n", n, err)
 		}
diff --git a/webseed/client.go b/webseed/client.go
index dc5858bc..10c8fcdf 100644
--- a/webseed/client.go
+++ b/webseed/client.go
@@ -46,17 +46,23 @@ type requestPart struct {
 }
 
 type Request struct {
+	// So you can view it from externally.
+	ctx    context.Context
 	cancel context.CancelCauseFunc
 	Body   io.Reader
 	// Closed with error to unstick copy routine when context isn't checked.
 	bodyPipe *io.PipeReader
 }
 
-func (r Request) Cancel(cause error) {
+func (r *Request) Context() context.Context {
+	return r.ctx
+}
+
+func (r *Request) Cancel(cause error) {
 	r.cancel(cause)
 }
 
-func (r Request) Close() {
+func (r *Request) Close() {
 	// We aren't cancelling because we want to know if we can keep receiving buffered data after
 	// cancellation. PipeReader.Close always returns nil.
 	_ = r.bodyPipe.Close()
@@ -144,6 +150,7 @@ func (ws *Client) StartNewRequest(ctx context.Context, r RequestSpec, debugLogge
 	panicif.Zero(len(requestParts))
 	body, w := io.Pipe()
 	req := Request{
+		ctx:      ctx,
 		cancel:   cancel,
 		Body:     body,
 		bodyPipe: body,