37 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			37 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// +build nacl linux solaris
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package godirwalk
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import (
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	"bytes"
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	"reflect"
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	"syscall"
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	"unsafe"
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)
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func nameFromDirent(de *syscall.Dirent) []byte {
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	// Because this GOOS' syscall.Dirent does not provide a field that specifies
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	// the name length, this function must first calculate the max possible name
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	// length, and then search for the NULL byte.
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	ml := int(uint64(de.Reclen) - uint64(unsafe.Offsetof(syscall.Dirent{}.Name)))
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	// Convert syscall.Dirent.Name, which is array of int8, to []byte, by
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	// overwriting Cap, Len, and Data slice header fields to values from
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	// syscall.Dirent fields. Setting the Cap, Len, and Data field values for
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	// the slice header modifies what the slice header points to, and in this
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	// case, the name buffer.
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	var name []byte
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	sh := (*reflect.SliceHeader)(unsafe.Pointer(&name))
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	sh.Cap = ml
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	sh.Len = ml
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	sh.Data = uintptr(unsafe.Pointer(&de.Name[0]))
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	if index := bytes.IndexByte(name, 0); index >= 0 {
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		// Found NULL byte; set slice's cap and len accordingly.
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		sh.Cap = index
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		sh.Len = index
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	}
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	return name
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}
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