net, internal/poll, net/internal/socktest: set SOCK_{CLOEXEC,NONBLOCK} atomically on NetBSD

NetBSD supports the SOCK_CLOEXEC and SOCK_NONBLOCK flags to the socket
syscall since version 6.0. The same version also introduced the paccept
syscall which can be used to implement syscall.Accept4.

Follows CL 40895

Change-Id: I9e4e1829b0382744c7799f4e58929a53b4e193f7
Reviewed-on: https://go-review.googlesource.com/94295
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/internal/poll/hook_cloexec.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build dragonfly freebsd linux
+// +build dragonfly freebsd linux netbsd
 
 package poll
 

src/internal/poll/sock_cloexec.go

@@ -5,7 +5,7 @@
 // This file implements sysSocket and accept for platforms that
 // provide a fast path for setting SetNonblock and CloseOnExec.
 
-// +build dragonfly freebsd linux
+// +build dragonfly freebsd linux netbsd
 
 package poll
 

src/internal/poll/sys_cloexec.go

@@ -5,7 +5,7 @@
 // This file implements sysSocket and accept for platforms that do not
 // provide a fast path for setting SetNonblock and CloseOnExec.
 
-// +build darwin nacl netbsd openbsd solaris
+// +build darwin nacl openbsd solaris
 
 package poll
 

src/net/internal/socktest/sys_cloexec.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build dragonfly freebsd linux
+// +build dragonfly freebsd linux netbsd
 
 package socktest
 

src/net/main_cloexec_test.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build dragonfly freebsd linux
+// +build dragonfly freebsd linux netbsd
 
 package net
 

src/net/sock_cloexec.go

@@ -5,7 +5,7 @@
 // This file implements sysSocket and accept for platforms that
 // provide a fast path for setting SetNonblock and CloseOnExec.
 
-// +build dragonfly freebsd linux
+// +build dragonfly freebsd linux netbsd
 
 package net
 

src/net/sys_cloexec.go

@@ -5,7 +5,7 @@
 // This file implements sysSocket and accept for platforms that do not
 // provide a fast path for setting SetNonblock and CloseOnExec.
 
-// +build darwin nacl netbsd openbsd solaris
+// +build darwin nacl openbsd solaris
 
 package net
 

src/syscall/syscall_netbsd.go

@@ -118,6 +118,25 @@ func Pipe2(p []int, flags int) error {
 	return err
 }
 
+//sys paccept(fd int, rsa *RawSockaddrAny, addrlen *_Socklen, sigmask *sigset, flags int) (nfd int, err error)
+func Accept4(fd, flags int) (nfd int, sa Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	nfd, err = paccept(fd, &rsa, &len, nil, flags)
+	if err != nil {
+		return
+	}
+	if len > SizeofSockaddrAny {
+		panic("RawSockaddrAny too small")
+	}
+	sa, err = anyToSockaddr(&rsa)
+	if err != nil {
+		Close(nfd)
+		nfd = 0
+	}
+	return
+}
+
 //sys getdents(fd int, buf []byte) (n int, err error)
 func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
 	return getdents(fd, buf)

src/syscall/types_netbsd.go

@@ -242,3 +242,7 @@ type Termios C.struct_termios
 // Sysctl
 
 type Sysctlnode C.struct_sysctlnode
+
+// Signals
+
+type sigset C.sigset_t

src/syscall/zsyscall_netbsd_386.go

@@ -271,6 +271,17 @@ func pipe2(p *[2]_C_int, flags int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func paccept(fd int, rsa *RawSockaddrAny, addrlen *_Socklen, sigmask *sigset, flags int) (nfd int, err error) {
+	r0, _, e1 := Syscall6(SYS_PACCEPT, uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)), uintptr(unsafe.Pointer(sigmask)), uintptr(flags), 0)
+	nfd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func getdents(fd int, buf []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(buf) > 0 {

src/syscall/zsyscall_netbsd_amd64.go

@@ -271,6 +271,17 @@ func pipe2(p *[2]_C_int, flags int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func paccept(fd int, rsa *RawSockaddrAny, addrlen *_Socklen, sigmask *sigset, flags int) (nfd int, err error) {
+	r0, _, e1 := Syscall6(SYS_PACCEPT, uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)), uintptr(unsafe.Pointer(sigmask)), uintptr(flags), 0)
+	nfd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func getdents(fd int, buf []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(buf) > 0 {

src/syscall/zsyscall_netbsd_arm.go

@@ -271,6 +271,17 @@ func pipe2(p *[2]_C_int, flags int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func paccept(fd int, rsa *RawSockaddrAny, addrlen *_Socklen, sigmask *sigset, flags int) (nfd int, err error) {
+	r0, _, e1 := Syscall6(SYS_PACCEPT, uintptr(fd), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)), uintptr(unsafe.Pointer(sigmask)), uintptr(flags), 0)
+	nfd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func getdents(fd int, buf []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(buf) > 0 {

src/syscall/ztypes_netbsd_386.go

@@ -402,3 +402,7 @@ type Sysctlnode struct {
 	X_sysctl_parent [8]byte
 	X_sysctl_desc   [8]byte
 }
+
+type sigset struct {
+	X__bits [4]uint32
+}

src/syscall/ztypes_netbsd_amd64.go

@@ -409,3 +409,7 @@ type Sysctlnode struct {
 	X_sysctl_parent [8]byte
 	X_sysctl_desc   [8]byte
 }
+
+type sigset struct {
+	X__bits [4]uint32
+}

src/syscall/ztypes_netbsd_arm.go

@@ -407,3 +407,7 @@ type Sysctlnode struct {
 	X_sysctl_parent [8]byte
 	X_sysctl_desc   [8]byte
 }
+
+type sigset struct {
+	X__bits [4]uint32
+}