browse: Show symbolic links and target's type properly (#1667)

* Browse: Show symbolic links and targets type properly
 * gofmt
Signed-off-by: Jonas Östanbäck <jonas.ostanback@gmail.com>

* Move symbolic link check in to isSymlinkTargetDir
Signed-off-by: Jonas Östanbäck <jonas.ostanback@gmail.com>

* Revert template change and show sym link folders as normal folders

* browse: Updated icons including symlink indicators

caddyhttp/browse/browse.go

@@ -118,6 +118,7 @@ type FileInfo struct {
 	ModTime   time.Time
 	Mode      os.FileMode
 	IsDir     bool
+	IsSymlink bool
 }
 
 // HumanSize returns the size of the file as a human-readable string
@@ -258,7 +259,8 @@ func directoryListing(files []os.FileInfo, canGoUp bool, urlPath string, config
 		url := url.URL{Path: "./" + name} // prepend with "./" to fix paths with ':' in the name
 
 		fileinfos = append(fileinfos, FileInfo{
-			IsDir:   f.IsDir(),
+			IsDir:     f.IsDir() || isSymlinkTargetDir(f),
+			IsSymlink: isSymlink(f),
 			Name:      f.Name(),
 			Size:      f.Size(),
 			URL:       url.String(),
@@ -277,6 +279,28 @@ func directoryListing(files []os.FileInfo, canGoUp bool, urlPath string, config
 	}, hasIndexFile
 }
 
+// isSymlink return true if f is a symbolic link
+func isSymlink(f os.FileInfo) bool {
+	return f.Mode()&os.ModeSymlink != 0
+}
+
+// isSymlinkTargetDir return true if f's symbolic link target
+// is a directory. Return false if not a symbolic link.
+func isSymlinkTargetDir(f os.FileInfo) bool {
+	if !isSymlink(f) {
+		return false
+	}
+	target, err := os.Readlink(f.Name())
+	if err != nil {
+		return false
+	}
+	targetInfo, err := os.Lstat(target)
+	if err != nil {
+		return false
+	}
+	return targetInfo.IsDir()
+}
+
 // ServeHTTP determines if the request is for this plugin, and if all prerequisites are met.
 // If so, control is handed over to ServeListing.
 func (b Browse) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {