fixed possible issue in uninstaller where file types without existing handlers could leave ours hanging in the registry added support for long paths to the dll

Author: ppound

src/handler.rs

@@ -136,7 +136,12 @@ impl PropertyHandler {
 }
 
 impl IInitializeWithFile_Impl for PropertyHandler_Impl {
-    fn Initialize(&self, pszfilepath: &PCWSTR, _grfmode: u32) -> Result<()> {
+    fn Initialize(&self, pszfilepath: &PCWSTR, grfmode: u32) -> Result<()> {
+        // Enforce read-only access (STGM_READ is 0; STGM_WRITE=1, STGM_READWRITE=2 are masked by 0x3)
+        if (grfmode & 0x3) != 0 {
+            return Err(Error::from(STG_E_ACCESSDENIED));
+        }
+
         let path_str = unsafe { pszfilepath.to_string()? };
         let path = Path::new(&path_str);
 

src/registry.rs

@@ -44,9 +44,9 @@ fn get_dll_path() -> Result<String> {
             PCWSTR(get_dll_path as *const () as usize as *const u16),
             &mut hmod,
         )?;
-        let mut buf = [0u16; 260];
-        let len = GetModuleFileNameW(hmod, &mut buf);
-        if len == 0 {
+        let mut buf = vec![0u16; 32768];
+        let len = GetModuleFileNameW(hmod, &mut buf[..]);
+        if len == 0 || len as usize >= buf.len() {
             return Err(Error::from_win32());
         }
         Ok(String::from_utf16_lossy(&buf[..len as usize]))
@@ -315,6 +315,10 @@ pub fn unregister() -> Result<()> {
                     unsafe {
                         let _ = RegDeleteValueW(hk, PCWSTR(w.as_ptr()));
                     }
+                } else {
+                    unsafe {
+                        let _ = RegDeleteValueW(hk, PCWSTR(core::ptr::null()));
+                    }
                 }
             }
             unsafe {