move SFTPGo package to the internal folder

SFTPGo is a daemon and command line tool, not a library.

The public API are provided by the SDK

Signed-off-by: Nicola Murino <nicola.murino@gmail.com>

internal/webdavd/mimecache.go

@@ -0,0 +1,49 @@
+// Copyright (C) 2019-2022  Nicola Murino
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published
+// by the Free Software Foundation, version 3.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package webdavd
+
+import "sync"
+
+type mimeCache struct {
+	maxSize int
+	sync.RWMutex
+	mimeTypes map[string]string
+}
+
+var mimeTypeCache mimeCache
+
+func (c *mimeCache) addMimeToCache(key, value string) {
+	c.Lock()
+	defer c.Unlock()
+
+	if key == "" || value == "" {
+		return
+	}
+
+	if len(c.mimeTypes) >= c.maxSize {
+		return
+	}
+	c.mimeTypes[key] = value
+}
+
+func (c *mimeCache) getMimeFromCache(key string) string {
+	c.RLock()
+	defer c.RUnlock()
+
+	if val, ok := c.mimeTypes[key]; ok {
+		return val
+	}
+	return ""
+}