37 lines
1.0 KiB
Go
37 lines
1.0 KiB
Go
|
// +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
|
||
|
|
}
|