1 files changed, 61 insertions, 0 deletions
diff --git a/shared/long_path_prefix.cpp b/shared/long_path_prefix.cpp
new file mode 100644
index 00000000..bc784f70
--- /dev/null
+++ b/shared/long_path_prefix.cpp
@@ -0,0 +1,61 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) 2008-2010 ZenJu (zhnmju123 AT gmx.de)                    *
+// **************************************************************************
+//
+#include "long_path_prefix.h"
+#include <wx/msw/wrapwin.h> //includes "windows.h"
+
+
+//there are two flavors of long path prefix: one for UNC paths, one for regular paths
+const Zstring LONG_PATH_PREFIX = DefaultStr("\\\\?\\");
+const Zstring LONG_PATH_PREFIX_UNC = DefaultStr("\\\\?\\UNC");
+
+template <size_t max_path>
+inline
+Zstring applyLongPathPrefixImpl(const Zstring& path)
+{
+    if (    path.length() >= max_path &&    //maximum allowed path length without prefix is (MAX_PATH - 1)
+            !path.StartsWith(LONG_PATH_PREFIX))
+    {
+        if (path.StartsWith(DefaultStr("\\\\"))) //UNC-name, e.g. \\zenju-pc\Users
+            return LONG_PATH_PREFIX_UNC + path.AfterFirst(DefaultChar('\\')); //convert to \\?\UNC\zenju-pc\Users
+        else
+            return LONG_PATH_PREFIX + path; //prepend \\?\ prefix
+    }
+
+    //fallback
+    return path;
+}
+
+
+Zstring ffs3::applyLongPathPrefix(const Zstring& path)
+{
+    return applyLongPathPrefixImpl<MAX_PATH>(path);
+}
+
+
+Zstring ffs3::applyLongPathPrefixCreateDir(const Zstring& path) //throw()
+{
+    //special rule for ::CreateDirectoryEx(): MAX_PATH - 12(=^ 8.3 filename) is threshold
+    return applyLongPathPrefixImpl<MAX_PATH - 12>(path);
+}
+
+
+Zstring ffs3::removeLongPathPrefix(const Zstring& path) //throw()
+{
+    if (path.StartsWith(LONG_PATH_PREFIX))
+    {
+        Zstring finalPath = path;
+        if (path.StartsWith(LONG_PATH_PREFIX_UNC)) //UNC-name
+            finalPath.Replace(LONG_PATH_PREFIX_UNC, DefaultStr("\\"), false);
+        else
+            finalPath.Replace(LONG_PATH_PREFIX, DefaultStr(""), false);
+        return finalPath;
+    }
+
+    //fallback
+    return path;
+}
+