Initial v1.0.0 commit

vendor/github.com/karrick/godirwalk/nameWithoutNamlen.go

@@ -0,0 +1,42 @@
+// +build nacl linux js solaris
+
+package godirwalk
+
+import (
+	"bytes"
+	"reflect"
+	"syscall"
+	"unsafe"
+)
+
+// nameOffset is a compile time constant
+const nameOffset = int(unsafe.Offsetof(syscall.Dirent{}.Name))
+
+func nameFromDirent(de *syscall.Dirent) (name []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(de.Reclen) - nameOffset
+
+	// Convert syscall.Dirent.Name, which is array of int8, to []byte, by
+	// overwriting Cap, Len, and Data slice header fields to the max possible
+	// name length computed above, and finding the terminating NULL 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
+	}
+
+	// NOTE: This branch is not expected, but included for defensive
+	// programming, and provides a hard stop on the name based on the structure
+	// field array size.
+	sh.Cap = len(de.Name)
+	sh.Len = sh.Cap
+	return
+}