go.net/ipv6: simplify syscall shims
This CL replaces syscall duplicates with tiny syscall shims to help
to add new platform support, to improve existing platform support.
LGTM=iant
R=iant
CC=golang-codereviews
https://golang.org/cl/166910043
diff --git a/ipv6/syscall_linux_386.go b/ipv6/syscall_linux_386.go
index c062325..82633a5 100644
--- a/ipv6/syscall_linux_386.go
+++ b/ipv6/syscall_linux_386.go
@@ -2,9 +2,6 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
-// This code is a duplicate of syscall/syscall_linux_386.go with small
-// modifications.
-
package ipv6
import (
@@ -12,30 +9,22 @@
"unsafe"
)
-// On x86 Linux, all the socket calls go through an extra indirection,
-// I think because the 5-register system call interface can't handle
-// the 6-argument calls like sendto and recvfrom. Instead the
-// arguments to the underlying system call are the number below and a
-// pointer to an array of uintptr. We hide the pointer in the
-// socketcall assembly to avoid allocation on every system call.
-
const (
- // See /usr/include/linux/net.h.
- _SETSOCKOPT = 14
- _GETSOCKOPT = 15
+ sysGETSOCKOPT = 0xf
+ sysSETSOCKOPT = 0xe
)
-var socketcall func(call int, a0, a1, a2, a3, a4, a5 uintptr) (int, syscall.Errno)
+func socketcall(call int, a0, a1, a2, a3, a4, a5 uintptr) (int, syscall.Errno)
-func getsockopt(fd int, level int, name int, v unsafe.Pointer, l *sysSockoptLen) error {
- if _, errno := socketcall(_GETSOCKOPT, uintptr(fd), uintptr(level), uintptr(name), uintptr(v), uintptr(unsafe.Pointer(l)), 0); errno != 0 {
+func getsockopt(fd, level, name int, v unsafe.Pointer, l *sysSockoptLen) error {
+ if _, errno := socketcall(sysGETSOCKOPT, uintptr(fd), uintptr(level), uintptr(name), uintptr(v), uintptr(unsafe.Pointer(l)), 0); errno != 0 {
return error(errno)
}
return nil
}
-func setsockopt(fd int, level int, name int, v unsafe.Pointer, l uintptr) error {
- if _, errno := socketcall(_SETSOCKOPT, uintptr(fd), uintptr(level), uintptr(name), uintptr(v), uintptr(l), 0); errno != 0 {
+func setsockopt(fd, level, name int, v unsafe.Pointer, l sysSockoptLen) error {
+ if _, errno := socketcall(sysSETSOCKOPT, uintptr(fd), uintptr(level), uintptr(name), uintptr(v), uintptr(l), 0); errno != 0 {
return error(errno)
}
return nil
