unix: use dup3 in Dup2 on all Linux platforms
The minimum required Linux kernel version for Go 1.18 will be changed to
2.6.32, see golang/go#45964. The dup3 syscall was added in 2.6.27, so it
can be used instead of the dup2 syscall which is not implemented on
arm64 and riscv64 or blocked on android.
For golang/go#45964
Change-Id: I9c677db4bae3ce441b258c49580fb9a2cd600436
Reviewed-on: https://go-review.googlesource.com/c/sys/+/350552
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matt Layher <mdlayher@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/unix/syscall_linux.go b/unix/syscall_linux.go
index a8ae8a5..6a2c5cd 100644
--- a/unix/syscall_linux.go
+++ b/unix/syscall_linux.go
@@ -13,7 +13,6 @@
import (
"encoding/binary"
- "runtime"
"syscall"
"unsafe"
)
@@ -1820,11 +1819,7 @@
//sys Dup(oldfd int) (fd int, err error)
func Dup2(oldfd, newfd int) error {
- // Android O and newer blocks dup2; riscv and arm64 don't implement dup2.
- if runtime.GOOS == "android" || runtime.GOARCH == "riscv64" || runtime.GOARCH == "arm64" {
- return Dup3(oldfd, newfd, 0)
- }
- return dup2(oldfd, newfd)
+ return Dup3(oldfd, newfd, 0)
}
//sys Dup3(oldfd int, newfd int, flags int) (err error)
diff --git a/unix/syscall_linux_386.go b/unix/syscall_linux_386.go
index 9ce9221..08b3f6a 100644
--- a/unix/syscall_linux_386.go
+++ b/unix/syscall_linux_386.go
@@ -21,7 +21,6 @@
// 64-bit file system and 32-bit uid calls
// (386 default is 32-bit file system and 16-bit uid).
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64_64
//sys Fchown(fd int, uid int, gid int) (err error) = SYS_FCHOWN32
diff --git a/unix/syscall_linux_amd64.go b/unix/syscall_linux_amd64.go
index f18b63a..dc31a15 100644
--- a/unix/syscall_linux_amd64.go
+++ b/unix/syscall_linux_amd64.go
@@ -7,7 +7,6 @@
package unix
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys Fchown(fd int, uid int, gid int) (err error)
diff --git a/unix/syscall_linux_arm.go b/unix/syscall_linux_arm.go
index 7d1dbd3..1d136ba 100644
--- a/unix/syscall_linux_arm.go
+++ b/unix/syscall_linux_arm.go
@@ -46,7 +46,6 @@
// 64-bit file system and 32-bit uid calls
// (16-bit uid calls are not always supported in newer kernels)
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fchown(fd int, uid int, gid int) (err error) = SYS_FCHOWN32
//sys Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
diff --git a/unix/syscall_linux_arm64.go b/unix/syscall_linux_arm64.go
index 75b40a9..9c715dc 100644
--- a/unix/syscall_linux_arm64.go
+++ b/unix/syscall_linux_arm64.go
@@ -180,10 +180,6 @@
rsa.Service_name_len = uint64(length)
}
-// dup2 exists because func Dup3 in syscall_linux.go references
-// it in an unreachable path. dup2 isn't available on arm64.
-func dup2(oldfd int, newfd int) error
-
func Pause() error {
_, err := ppoll(nil, 0, nil, nil)
return err
diff --git a/unix/syscall_linux_mips64x.go b/unix/syscall_linux_mips64x.go
index 36b2752..d47ceaf 100644
--- a/unix/syscall_linux_mips64x.go
+++ b/unix/syscall_linux_mips64x.go
@@ -8,7 +8,6 @@
package unix
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys Fchown(fd int, uid int, gid int) (err error)
diff --git a/unix/syscall_linux_mipsx.go b/unix/syscall_linux_mipsx.go
index d0b8b23..27ee4db 100644
--- a/unix/syscall_linux_mipsx.go
+++ b/unix/syscall_linux_mipsx.go
@@ -15,7 +15,6 @@
func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err syscall.Errno)
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys Fchown(fd int, uid int, gid int) (err error)
diff --git a/unix/syscall_linux_ppc.go b/unix/syscall_linux_ppc.go
index c28fa34..299ba9d 100644
--- a/unix/syscall_linux_ppc.go
+++ b/unix/syscall_linux_ppc.go
@@ -12,7 +12,6 @@
"unsafe"
)
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fchown(fd int, uid int, gid int) (err error)
//sys Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
diff --git a/unix/syscall_linux_ppc64x.go b/unix/syscall_linux_ppc64x.go
index 2ba4aa7..0873b07 100644
--- a/unix/syscall_linux_ppc64x.go
+++ b/unix/syscall_linux_ppc64x.go
@@ -8,7 +8,6 @@
package unix
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys Fchown(fd int, uid int, gid int) (err error)
diff --git a/unix/syscall_linux_riscv64.go b/unix/syscall_linux_riscv64.go
index 97468c5..e2c5b32 100644
--- a/unix/syscall_linux_riscv64.go
+++ b/unix/syscall_linux_riscv64.go
@@ -194,7 +194,3 @@
}
return kexecFileLoad(kernelFd, initrdFd, cmdlineLen, cmdline, flags)
}
-
-// dup2 exists because func Dup3 in syscall_linux.go references
-// it in an unreachable path. dup2 isn't available on arm64.
-func dup2(oldfd int, newfd int) error
diff --git a/unix/syscall_linux_s390x.go b/unix/syscall_linux_s390x.go
index 3236fee..dfa204d 100644
--- a/unix/syscall_linux_s390x.go
+++ b/unix/syscall_linux_s390x.go
@@ -11,7 +11,6 @@
"unsafe"
)
-//sys dup2(oldfd int, newfd int) (err error)
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys Fchown(fd int, uid int, gid int) (err error)
diff --git a/unix/syscall_linux_sparc64.go b/unix/syscall_linux_sparc64.go
index 0544d96..4c54e09 100644
--- a/unix/syscall_linux_sparc64.go
+++ b/unix/syscall_linux_sparc64.go
@@ -9,7 +9,6 @@
//sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
-//sys dup2(oldfd int, newfd int) (err error)
//sys Fchown(fd int, uid int, gid int) (err error)
//sys Fstat(fd int, stat *Stat_t) (err error)
//sys Fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64
diff --git a/unix/zsyscall_linux_386.go b/unix/zsyscall_linux_386.go
index f32cec9..7f3eccf 100644
--- a/unix/zsyscall_linux_386.go
+++ b/unix/zsyscall_linux_386.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_amd64.go b/unix/zsyscall_linux_amd64.go
index c9bf2fe..c1c9ac4 100644
--- a/unix/zsyscall_linux_amd64.go
+++ b/unix/zsyscall_linux_amd64.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_arm.go b/unix/zsyscall_linux_arm.go
index 39cca71..d89b8be 100644
--- a/unix/zsyscall_linux_arm.go
+++ b/unix/zsyscall_linux_arm.go
@@ -225,16 +225,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_mips.go b/unix/zsyscall_linux_mips.go
index 1bf9898..9e609dd 100644
--- a/unix/zsyscall_linux_mips.go
+++ b/unix/zsyscall_linux_mips.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_mips64.go b/unix/zsyscall_linux_mips64.go
index f7d253f..46b1d82 100644
--- a/unix/zsyscall_linux_mips64.go
+++ b/unix/zsyscall_linux_mips64.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_mips64le.go b/unix/zsyscall_linux_mips64le.go
index f5799bf..ab2f9db 100644
--- a/unix/zsyscall_linux_mips64le.go
+++ b/unix/zsyscall_linux_mips64le.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_mipsle.go b/unix/zsyscall_linux_mipsle.go
index 199e4ef..0d4a48b 100644
--- a/unix/zsyscall_linux_mipsle.go
+++ b/unix/zsyscall_linux_mipsle.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_ppc.go b/unix/zsyscall_linux_ppc.go
index daff312..078f1cc 100644
--- a/unix/zsyscall_linux_ppc.go
+++ b/unix/zsyscall_linux_ppc.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_ppc64.go b/unix/zsyscall_linux_ppc64.go
index aa164b2..791efbb 100644
--- a/unix/zsyscall_linux_ppc64.go
+++ b/unix/zsyscall_linux_ppc64.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_ppc64le.go b/unix/zsyscall_linux_ppc64le.go
index f289eac..dbc7621 100644
--- a/unix/zsyscall_linux_ppc64le.go
+++ b/unix/zsyscall_linux_ppc64le.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_s390x.go b/unix/zsyscall_linux_s390x.go
index d7bf4b1..8f65b2e 100644
--- a/unix/zsyscall_linux_s390x.go
+++ b/unix/zsyscall_linux_s390x.go
@@ -46,16 +46,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
var _p0 unsafe.Pointer
if len(events) > 0 {
diff --git a/unix/zsyscall_linux_sparc64.go b/unix/zsyscall_linux_sparc64.go
index 8329e91..227f0f8 100644
--- a/unix/zsyscall_linux_sparc64.go
+++ b/unix/zsyscall_linux_sparc64.go
@@ -73,16 +73,6 @@
// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-func dup2(oldfd int, newfd int) (err error) {
- _, _, e1 := Syscall(SYS_DUP2, uintptr(oldfd), uintptr(newfd), 0)
- if e1 != 0 {
- err = errnoErr(e1)
- }
- return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
func Fchown(fd int, uid int, gid int) (err error) {
_, _, e1 := Syscall(SYS_FCHOWN, uintptr(fd), uintptr(uid), uintptr(gid))
if e1 != 0 {
