From 5b7eb71cfe22abb59c481d3cee3a719ff6d88095 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Tue, 5 Oct 2021 19:08:31 +0300
Subject: [PATCH] R/W deadlines on connections
---
cmd/godlighty/main.go | 13 +++++--
conn.go | 79 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 89 insertions(+), 3 deletions(-)
create mode 100644 conn.go
diff --git a/cmd/godlighty/main.go b/cmd/godlighty/main.go
index 4198753..e15c165 100644
--- a/cmd/godlighty/main.go
+++ b/cmd/godlighty/main.go
@@ -40,7 +40,10 @@ import (
const MaxConns = 128
-var GracefulTime = 10 * time.Second
+var (
+ GracefulTime = 10 * time.Second
+ RWTimeout = 30 * time.Second
+)
func main() {
bind := flag.String("bind", "[::]:80", "Address to bind and listen on")
@@ -57,7 +60,7 @@ func main() {
shutdown := make(chan os.Signal)
signal.Notify(shutdown, syscall.SIGTERM, syscall.SIGINT, syscall.SIGHUP)
exitErr := make(chan error)
- l, err := net.Listen("tcp", *bind)
+ l, err := godlighty.DeadlinedListen("tcp", *bind, RWTimeout, RWTimeout)
if err != nil {
log.Fatalln(err)
}
@@ -101,7 +104,11 @@ func main() {
}
}()
- srv := http.Server{Handler: godlighty.MainHandler}
+ srv := http.Server{
+ Handler: godlighty.MainHandler,
+ ReadHeaderTimeout: RWTimeout,
+ IdleTimeout: time.Minute,
+ }
go func() {
<-shutdown
log.Println("shutting down")
diff --git a/conn.go b/conn.go
new file mode 100644
index 0000000..81ec846
--- /dev/null
+++ b/conn.go
@@ -0,0 +1,79 @@
+// Deadlined socket read/write. https://github.com/golang/go/issues/16100
+
+package godlighty
+
+import (
+ "net"
+ "time"
+)
+
+type DeadlinedConn struct {
+ net.Conn
+ ReadTimeout time.Duration
+ WriteTimeout time.Duration
+ ReadThreshold int64
+ WriteThreshold int64
+ BytesReadFromDeadline int64
+ BytesWrittenFromDeadline int64
+}
+
+func (c *DeadlinedConn) Read(b []byte) (n int, err error) {
+ if c.BytesReadFromDeadline > c.ReadThreshold {
+ c.BytesReadFromDeadline = 0
+ err = c.Conn.SetDeadline(time.Now().Add(c.ReadTimeout))
+ if err != nil {
+ return
+ }
+ }
+ n, err = c.Conn.Read(b)
+ c.BytesReadFromDeadline += int64(n)
+ return
+}
+
+func (c *DeadlinedConn) Write(b []byte) (n int, err error) {
+ if c.BytesWrittenFromDeadline > c.WriteThreshold {
+ c.BytesWrittenFromDeadline = 0
+ err = c.Conn.SetWriteDeadline(time.Now().Add(c.WriteTimeout))
+ if err != nil {
+ return
+ }
+ }
+ n, err = c.Conn.Write(b)
+ c.BytesWrittenFromDeadline += int64(n)
+ return
+}
+
+type DeadlinedListener struct {
+ net.Listener
+ ReadTimeout time.Duration
+ WriteTimeout time.Duration
+}
+
+func (l *DeadlinedListener) Accept() (net.Conn, error) {
+ c, err := l.Listener.Accept()
+ if err != nil {
+ return nil, err
+ }
+ return &DeadlinedConn{
+ Conn: c,
+ ReadTimeout: l.ReadTimeout,
+ WriteTimeout: l.WriteTimeout,
+ ReadThreshold: int64((l.ReadTimeout * 1024) / time.Second),
+ WriteThreshold: int64((l.WriteTimeout * 1024) / time.Second),
+ }, nil
+}
+
+func DeadlinedListen(
+ network, addr string,
+ readTimeout, writeTimeout time.Duration,
+) (net.Listener, error) {
+ l, err := net.Listen(network, addr)
+ if err != nil {
+ return nil, err
+ }
+ return &DeadlinedListener{
+ Listener: l,
+ ReadTimeout: readTimeout,
+ WriteTimeout: writeTimeout,
+ }, nil
+}
--
2.51.0