31 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Go
		
	
	
	
		
		
			
		
	
	
			31 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Go
		
	
	
	
|  | // Copyright 2017 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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|  | 
 | ||
|  | // Functions to access/create device major and minor numbers matching the
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|  | // encoding used in Dragonfly's sys/types.h header.
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|  | //
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|  | // The information below is extracted and adapted from sys/types.h:
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|  | //
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|  | // Minor gives a cookie instead of an index since in order to avoid changing the
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|  | // meanings of bits 0-15 or wasting time and space shifting bits 16-31 for
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|  | // devices that don't use them.
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|  | 
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|  | package unix | ||
|  | 
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|  | // Major returns the major component of a DragonFlyBSD device number.
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|  | func Major(dev uint64) uint32 { | ||
|  | 	return uint32((dev >> 8) & 0xff) | ||
|  | } | ||
|  | 
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|  | // Minor returns the minor component of a DragonFlyBSD device number.
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|  | func Minor(dev uint64) uint32 { | ||
|  | 	return uint32(dev & 0xffff00ff) | ||
|  | } | ||
|  | 
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|  | // Mkdev returns a DragonFlyBSD device number generated from the given major and
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|  | // minor components.
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|  | func Mkdev(major, minor uint32) uint64 { | ||
|  | 	return (uint64(major) << 8) | uint64(minor) | ||
|  | } |