Add a function to create long paths on windows

libs/kiplatform/include/kiplatform/io.h

@@ -23,6 +23,7 @@
 #include <stdio.h>
 
 class wxString;
+class wxFileName;
 
 namespace KIPLATFORM
 {
@@ -50,6 +51,12 @@ namespace IO
     * @return true if the file attribut is set.
     */
     bool IsFileHidden( const wxString& aFileName );
+
+    /**
+     * Adjusts a filename to be a long path compatible.
+     * This is a no-op on non-Windows platforms.
+     */
+    void LongPathAdjustment( wxFileName& aFilename );
 } // namespace IO
 } // namespace KIPLATFORM
 

libs/kiplatform/os/apple/io.mm

@@ -49,16 +49,16 @@ bool KIPLATFORM::IO::DuplicatePermissions(const wxString& sourceFilePath, const
 
     NSNumber *permissions = sourceAttributes[NSFilePosixPermissions];
 
-    if (permissions == nil) 
+    if (permissions == nil)
     {
         return false;
     }
 
-    if ([fileManager setAttributes:@{NSFilePosixPermissions: permissions} ofItemAtPath:destPath error:&error]) 
+    if ([fileManager setAttributes:@{NSFilePosixPermissions: permissions} ofItemAtPath:destPath error:&error])
     {
         return true;
-    } 
-    else 
+    }
+    else
     {
         NSLog(@"Error assigning permissions: %@", error);
         return false;
@@ -71,3 +71,9 @@ bool KIPLATFORM::IO::IsFileHidden( const wxString& aFileName )
 
     return fn.GetName().StartsWith( wxT( "." ) );
 }
+
+
+void KIPLATFORM::IO::LongPathAdjustment( wxFileName& aFilename )
+{
+    // no-op
+}

libs/kiplatform/os/unix/io.cpp

@@ -66,3 +66,9 @@ bool KIPLATFORM::IO::IsFileHidden( const wxString& aFileName )
 
     return fn.GetName().StartsWith( wxT( "." ) );
 }
+
+
+void KIPLATFORM::IO::LongPathAdjustment( wxFileName& aFilename )
+{
+    // no-op
+}

libs/kiplatform/os/windows/io.cpp

@@ -21,7 +21,7 @@
 
 #include <wx/string.h>
 #include <wx/wxcrt.h>
-
+#include <wx/filename.h>
 #include <windows.h>
 
 // Define USE_MSYS2_FALlBACK if the code for _MSC_VER does not compile on msys2
@@ -123,4 +123,24 @@ bool KIPLATFORM::IO::IsFileHidden( const wxString& aFileName )
         result = true;
 
     return result;
+}
+
+
+void KIPLATFORM::IO::LongPathAdjustment( wxFileName& aFilename )
+{
+    // dont shortcut this for shorter lengths as there are uses like directory
+    // paths that exceed the path length when you start traversing their subdirectories
+    // so we want to start with the long path prefix all the time
+
+    if( aFilename.GetVolume().Length() == 1 )
+        // assume single letter == drive volume
+        aFilename.SetVolume( "\\\\?\\" + aFilename.GetVolume() + ":" );
+    else if( aFilename.GetVolume().Length() > 1
+            && aFilename.GetVolume().StartsWith( wxT( "\\\\" ) )
+            && !aFilename.GetVolume().StartsWith( wxT( "\\\\?\\" ) ) )
+        // unc path aka network share, wx returns with \\ already
+        // so skip the first slash and combine with the prefix
+        // which in the case of UNCs is actually \\?\UNC\<server>\<share>
+        // where UNC is literally the text UNC
+        aFilename.SetVolume( "\\\\?\\UNC" + aFilename.GetVolume().Mid(1) );
 }