| // Copyright 2019 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 aix darwin freebsd hurd linux netbsd openbsd solaris |
| |
| package syscall |
| |
| import ( |
| "runtime" |
| ) |
| |
| // Round the length of a raw sockaddr up to align it properly. |
| func cmsgAlignOf(salen int) int { |
| salign := int(sizeofPtr) |
| |
| // dragonfly needs to check ABI version at runtime, see cmsgAlignOf in |
| // sockcmsg_dragonfly.go |
| switch runtime.GOOS { |
| case "aix": |
| // There is no alignment on AIX. |
| salign = 1 |
| case "darwin", "ios", "illumos", "solaris": |
| // NOTE: It seems like 64-bit Darwin, Illumos and Solaris |
| // kernels still require 32-bit aligned access to network |
| // subsystem. |
| if sizeofPtr == 8 { |
| salign = 4 |
| } |
| case "netbsd", "openbsd": |
| // NetBSD and OpenBSD armv7 require 64-bit alignment. |
| if runtime.GOARCH == "arm" { |
| salign = 8 |
| } |
| // NetBSD aarch64 requires 128-bit alignment. |
| if runtime.GOOS == "netbsd" && runtime.GOARCH == "arm64" { |
| salign = 16 |
| } |
| } |
| |
| return (salen + salign - 1) & ^(salign - 1) |
| } |