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