Revert "util: Add ArcWrapped"

This reverts commit 5c1b28e4ed8b046a251609e5f7db4b4df9e710f5.

It has only been needed to move Rust structure across C bridges. That's unneeded with more integration.

src/util.rs

@@ -16,7 +16,6 @@ pub mod c {
     use std::os::raw::c_char;
     use std::rc::Rc;
     use std::str::Utf8Error;
-    use std::sync::{ Arc, Mutex };
 
     // traits
     
@@ -130,40 +129,6 @@ pub mod c {
     }
 
     impl<T> COpaquePtr for Wrapped<T> {}
-    
-    #[repr(transparent)]
-    pub struct ArcWrapped<T>(*const Mutex<T>);
-    
-    impl<T> ArcWrapped<T> {
-        pub fn new(value: T) -> Self {
-            Self::wrap(Arc::new(Mutex::new(value)))
-        }
-        pub fn wrap(state: Arc<Mutex<T>>) -> Self {
-            Self(Arc::into_raw(state))
-        }
-        
-        /// Extracts the reference to the data.
-        /// It may cause problems if attempted in more than one place
-        pub unsafe fn unwrap(self) -> Arc<Mutex<T>> {
-            Arc::from_raw(self.0)
-        }
-        
-        /// Creates a new reference to the same data.
-        /// Use for accessing the underlying data as a reference.
-        pub fn clone_ref(&self) -> Arc<Mutex<T>> {
-            // A bit dangerous: the Arc may be in use elsewhere
-            let used_rc = unsafe { Arc::from_raw(self.0) };
-            let rc = used_rc.clone();
-            Arc::into_raw(used_rc); // prevent dropping the original reference
-            rc
-        }
-    }
-
-    impl<T> Clone for ArcWrapped<T> {
-        fn clone(&self) -> Self {
-            Self::wrap(self.clone_ref())
-        }
-    }
 }
 
 /// Clones the underlying data structure, like ToOwned.