rust: support memory

Author: axic

bindings/rust/src/lib.rs

@@ -139,6 +139,38 @@ impl From<ExecutionResult> for sys::FizzyExecutionResult {
 }
 
 impl Instance {
+    fn checked_memory_range(&self, offset: u32) -> core::ops::Range<usize> {
+        let offset = offset as usize;
+        let size = 0 as usize;
+        offset..offset + size
+    }
+
+    pub fn memory_size(&self) -> usize {
+        unsafe { sys::fizzy_get_instance_memory_size(self.0.as_ptr()) }
+    }
+
+    pub fn memory_get_into(&mut self, offset: u32, target: &mut [u8]) -> Result<(), ()> {
+        let mem = unsafe {
+            std::slice::from_raw_parts(
+                sys::fizzy_get_instance_memory_data(self.0.as_ptr()),
+                sys::fizzy_get_instance_memory_size(self.0.as_ptr()),
+            )
+        };
+        target.copy_from_slice(&mem[self.checked_memory_range(offset)]);
+        Ok(())
+    }
+
+    pub fn memory_set(&mut self, offset: u32, value: &[u8]) -> Result<(), ()> {
+        let mem = unsafe {
+            std::slice::from_raw_parts_mut(
+                sys::fizzy_get_instance_memory_data(self.0.as_ptr()),
+                sys::fizzy_get_instance_memory_size(self.0.as_ptr()),
+            )
+        };
+        mem[self.checked_memory_range(offset)].copy_from_slice(value);
+        Ok(())
+    }
+
     pub unsafe fn unsafe_execute(&mut self, func_idx: u32, args: &[Value]) -> ExecutionResult {
         ExecutionResult {
             0: sys::fizzy_execute(self.0.as_ptr(), func_idx, args.as_ptr(), 0),