cubefs

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// Copyright 2019 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:build aix || darwin || freebsd || linux || netbsd || openbsd || solaris || zos
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// +build aix darwin freebsd linux netbsd openbsd solaris zos
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package unix
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import (
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	"runtime"
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)
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// Round the length of a raw sockaddr up to align it properly.
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func cmsgAlignOf(salen int) int {
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	salign := SizeofPtr
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	// dragonfly needs to check ABI version at runtime, see cmsgAlignOf in
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	// sockcmsg_dragonfly.go
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	switch runtime.GOOS {
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	case "aix":
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		// There is no alignment on AIX.
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		salign = 1
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	case "darwin", "ios", "illumos", "solaris":
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		// NOTE: It seems like 64-bit Darwin, Illumos and Solaris
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		// kernels still require 32-bit aligned access to network
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		// subsystem.
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		if SizeofPtr == 8 {
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			salign = 4
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		}
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	case "netbsd", "openbsd":
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		// NetBSD and OpenBSD armv7 require 64-bit alignment.
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		if runtime.GOARCH == "arm" {
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			salign = 8
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		}
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		// NetBSD aarch64 requires 128-bit alignment.
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		if runtime.GOOS == "netbsd" && runtime.GOARCH == "arm64" {
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			salign = 16
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		}
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	case "zos":
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		// z/OS socket macros use [32-bit] sizeof(int) alignment,
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		// not pointer width.
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		salign = SizeofInt
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	}
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	return (salen + salign - 1) & ^(salign - 1)
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}
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