net: make use of the kernel state to listen on TCP, Unix
R=golang-dev, dave, minux.ma
CC=golang-dev
https://golang.org/cl/5545044
diff --git a/src/pkg/net/Makefile b/src/pkg/net/Makefile
index f3d77c7..81df2a2 100644
--- a/src/pkg/net/Makefile
+++ b/src/pkg/net/Makefile
@@ -36,6 +36,7 @@
port.go\
sendfile_stub.go\
sock.go\
+ sock_bsd.go\
sockopt.go\
sockopt_bsd.go\
sockoptip.go\
@@ -68,6 +69,7 @@
port.go\
sendfile_stub.go\
sock.go\
+ sock_bsd.go\
sockopt.go\
sockopt_bsd.go\
sockoptip.go\
@@ -99,6 +101,7 @@
port.go\
sendfile_linux.go\
sock.go\
+ sock_linux.go\
sockopt.go\
sockopt_linux.go\
sockoptip.go\
@@ -130,6 +133,7 @@
port.go\
sendfile_stub.go\
sock.go\
+ sock_bsd.go\
sockopt.go\
sockopt_bsd.go\
sockoptip.go\
@@ -155,6 +159,7 @@
port.go\
sendfile_stub.go\
sock.go\
+ sock_bsd.go\
sockopt.go\
sockopt_bsd.go\
sockoptip.go\
@@ -184,6 +189,7 @@
lookup_windows.go\
sendfile_windows.go\
sock.go\
+ sock_windows.go\
sockopt.go\
sockopt_windows.go\
sockoptip.go\
diff --git a/src/pkg/net/ipsock_posix.go b/src/pkg/net/ipsock_posix.go
index d141c05..45fe0d9 100644
--- a/src/pkg/net/ipsock_posix.go
+++ b/src/pkg/net/ipsock_posix.go
@@ -91,11 +91,6 @@
return syscall.AF_INET6
}
-// TODO(rsc): if syscall.OS == "linux", we're supposed to read
-// /proc/sys/net/core/somaxconn,
-// to take advantage of kernels that have raised the limit.
-func listenBacklog() int { return syscall.SOMAXCONN }
-
// Internet sockets (TCP, UDP)
// A sockaddr represents a TCP or UDP network address that can
diff --git a/src/pkg/net/sock.go b/src/pkg/net/sock.go
index 3ed0720..7732d2e 100644
--- a/src/pkg/net/sock.go
+++ b/src/pkg/net/sock.go
@@ -14,6 +14,8 @@
"syscall"
)
+var listenerBacklog = maxListenerBacklog()
+
// Generic socket creation.
func socket(net string, f, p, t int, la, ra syscall.Sockaddr, toAddr func(syscall.Sockaddr) Addr) (fd *netFD, err error) {
// See ../syscall/exec.go for description of ForkLock.
diff --git a/src/pkg/net/sock_bsd.go b/src/pkg/net/sock_bsd.go
new file mode 100644
index 0000000..630a91ed
--- /dev/null
+++ b/src/pkg/net/sock_bsd.go
@@ -0,0 +1,33 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin freebsd netbsd openbsd
+
+// Sockets for BSD variants
+
+package net
+
+import (
+ "runtime"
+ "syscall"
+)
+
+func maxListenerBacklog() int {
+ var (
+ n uint32
+ err error
+ )
+ switch runtime.GOOS {
+ case "darwin", "freebsd":
+ n, err = syscall.SysctlUint32("kern.ipc.somaxconn")
+ case "netbsd":
+ // NOTE: NetBSD has no somaxconn-like kernel state so far
+ case "openbsd":
+ n, err = syscall.SysctlUint32("kern.somaxconn")
+ }
+ if n == 0 || err != nil {
+ return syscall.SOMAXCONN
+ }
+ return int(n)
+}
diff --git a/src/pkg/net/sock_linux.go b/src/pkg/net/sock_linux.go
new file mode 100644
index 0000000..2cbc34f
--- /dev/null
+++ b/src/pkg/net/sock_linux.go
@@ -0,0 +1,27 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Sockets for Linux
+
+package net
+
+import "syscall"
+
+func maxListenerBacklog() int {
+ fd, err := open("/proc/sys/net/core/somaxconn")
+ if err != nil {
+ return syscall.SOMAXCONN
+ }
+ defer fd.close()
+ l, ok := fd.readLine()
+ if !ok {
+ return syscall.SOMAXCONN
+ }
+ f := getFields(l)
+ n, _, ok := dtoi(f[0], 0)
+ if n == 0 || !ok {
+ return syscall.SOMAXCONN
+ }
+ return n
+}
diff --git a/src/pkg/net/sock_windows.go b/src/pkg/net/sock_windows.go
new file mode 100644
index 0000000..2d803de
--- /dev/null
+++ b/src/pkg/net/sock_windows.go
@@ -0,0 +1,14 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Sockets for Windows
+
+package net
+
+import "syscall"
+
+func maxListenerBacklog() int {
+ // TODO: Implement this
+ return syscall.SOMAXCONN
+}
diff --git a/src/pkg/net/tcpsock_posix.go b/src/pkg/net/tcpsock_posix.go
index a7c09c7..a492e61 100644
--- a/src/pkg/net/tcpsock_posix.go
+++ b/src/pkg/net/tcpsock_posix.go
@@ -249,10 +249,10 @@
if err != nil {
return nil, err
}
- errno := syscall.Listen(fd.sysfd, listenBacklog())
- if errno != nil {
+ err = syscall.Listen(fd.sysfd, listenerBacklog)
+ if err != nil {
closesocket(fd.sysfd)
- return nil, &OpError{"listen", "tcp", laddr, errno}
+ return nil, &OpError{"listen", "tcp", laddr, err}
}
l = new(TCPListener)
l.fd = fd
diff --git a/src/pkg/net/unixsock_posix.go b/src/pkg/net/unixsock_posix.go
index 10632c1..00ee016 100644
--- a/src/pkg/net/unixsock_posix.go
+++ b/src/pkg/net/unixsock_posix.go
@@ -315,7 +315,7 @@
// ListenUnix announces on the Unix domain socket laddr and returns a Unix listener.
// Net must be "unix" (stream sockets).
-func ListenUnix(net string, laddr *UnixAddr) (l *UnixListener, err error) {
+func ListenUnix(net string, laddr *UnixAddr) (*UnixListener, error) {
if net != "unix" && net != "unixgram" && net != "unixpacket" {
return nil, UnknownNetworkError(net)
}
@@ -326,10 +326,10 @@
if err != nil {
return nil, err
}
- e1 := syscall.Listen(fd.sysfd, 8) // listenBacklog());
- if e1 != nil {
+ err = syscall.Listen(fd.sysfd, listenerBacklog)
+ if err != nil {
closesocket(fd.sysfd)
- return nil, &OpError{Op: "listen", Net: "unix", Addr: laddr, Err: e1}
+ return nil, &OpError{Op: "listen", Net: "unix", Addr: laddr, Err: err}
}
return &UnixListener{fd, laddr.Name}, nil
}
