From 0abb6b668c708aa84daba4b036e536fd76a8b1c5 Mon Sep 17 00:00:00 2001
From: Avery Pennarun <apenwarr@gmail.com>
Date: Sat, 12 Oct 2019 00:46:13 -0700
Subject: [PATCH] rwcancel: handle EINTR and EAGAIN in unixSelect()
On my Chromebook (Linux 4.19.44 in a VM) and on an AWS EC2
machine, select() was sometimes returning EINTR. This is
harmless and just means you should try again. So let's try
again.
This eliminates a problem where the tunnel fails to come up
correctly and the program needs to be restarted.
Signed-off-by: Avery Pennarun <apenwarr@gmail.com>
---
rwcancel/rwcancel.go | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/rwcancel/rwcancel.go b/rwcancel/rwcancel.go
index 62397c2..808e691 100644
--- a/rwcancel/rwcancel.go
+++ b/rwcancel/rwcancel.go
@@ -60,7 +60,13 @@ func (rw *RWCancel) ReadyRead() bool {
fdset := fdSet{}
fdset.set(rw.fd)
fdset.set(closeFd)
- err := unixSelect(max(rw.fd, closeFd)+1, &fdset.FdSet, nil, nil, nil)
+ var err error
+ for {
+ err = unixSelect(max(rw.fd, closeFd)+1, &fdset.FdSet, nil, nil, nil)
+ if err == nil || !RetryAfterError(err) {
+ break
+ }
+ }
if err != nil {
return false
}
@@ -75,7 +81,13 @@ func (rw *RWCancel) ReadyWrite() bool {
fdset := fdSet{}
fdset.set(rw.fd)
fdset.set(closeFd)
- err := unixSelect(max(rw.fd, closeFd)+1, nil, &fdset.FdSet, nil, nil)
+ var err error
+ for {
+ err = unixSelect(max(rw.fd, closeFd)+1, nil, &fdset.FdSet, nil, nil)
+ if err == nil || !RetryAfterError(err) {
+ break
+ }
+ }
if err != nil {
return false
}