server: Move all the top level files into cmd folder. (#2490)

This change brings a change which was done for the 'mc'
package to allow for clean repo and have a cleaner
github drop in experience.

cmd/posix-list-dir-others.go

@@ -0,0 +1,84 @@
+// +build !linux,!darwin,!openbsd,!freebsd,!netbsd,!dragonfly
+
+/*
+ * Minio Cloud Storage, (C) 2016 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package cmd
+
+import (
+	"io"
+	"os"
+	"path"
+	"strings"
+)
+
+// Return all the entries at the directory dirPath.
+func readDir(dirPath string) (entries []string, err error) {
+	d, err := os.Open(preparePath(dirPath))
+	if err != nil {
+		// File is really not found.
+		if os.IsNotExist(err) {
+			return nil, errFileNotFound
+		}
+
+		// File path cannot be verified since one of the parents is a file.
+		if strings.Contains(err.Error(), "not a directory") {
+			return nil, errFileNotFound
+		}
+		return nil, err
+	}
+	defer d.Close()
+
+	for {
+		// Read 1000 entries.
+		fis, err := d.Readdir(1000)
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return nil, err
+		}
+		for _, fi := range fis {
+			// Skip special files, if found.
+			if hasPosixReservedPrefix(fi.Name()) {
+				continue
+			}
+			// Stat symbolic link and follow to get the final value.
+			if fi.Mode()&os.ModeSymlink == os.ModeSymlink {
+				var st os.FileInfo
+				st, err = os.Stat(preparePath(path.Join(dirPath, fi.Name())))
+				if err != nil {
+					errorIf(err, "Unable to stat path %s", path.Join(dirPath, fi.Name()))
+					continue
+				}
+				// Append to entries if symbolic link exists and is valid.
+				if st.IsDir() {
+					entries = append(entries, fi.Name()+slashSeparator)
+				} else if st.Mode().IsRegular() {
+					entries = append(entries, fi.Name())
+				}
+				continue
+			}
+			if fi.Mode().IsDir() {
+				// Append "/" instead of "\" so that sorting is achieved as expected.
+				entries = append(entries, fi.Name()+slashSeparator)
+			} else if fi.Mode().IsRegular() {
+				entries = append(entries, fi.Name())
+			}
+		}
+	}
+	return entries, nil
+}