add backend

src/backend.rs

@@ -0,0 +1,33 @@
+use sptr::Strict;
+
+pub trait Backend<T> {
+    type Stored: Copy;
+
+    fn get_ptr(s: Self::Stored) -> (*mut T, Self);
+
+    fn set_ptr(provenance: *mut T, addr: Self) -> Self::Stored;
+
+    fn get_int(s: Self::Stored) -> Self;
+
+    fn set_int(s: Self::Stored, int: Self) -> Self::Stored;
+}
+
+impl<T> Backend<T> for usize {
+    type Stored = *mut T;
+
+    fn get_ptr(s: Self::Stored) -> (*mut T, Self) {
+        (s, Strict::addr(s))
+    }
+
+    fn set_ptr(provenance: *mut T, addr: Self) -> Self::Stored {
+        Strict::with_addr(provenance, addr)
+    }
+
+    fn get_int(s: Self::Stored) -> Self {
+        Strict::addr(s)
+    }
+
+    fn set_int(s: Self::Stored, int: Self) -> Self::Stored {
+        Strict::with_addr(s, int)
+    }
+}