add Reply::as_raw

See #265

build/cg/request.rs

@@ -354,6 +354,10 @@ impl CodeGen {
         writeln!(out, "        std::mem::forget(self);")?;
         writeln!(out, "        raw")?;
         writeln!(out, "    }}")?;
+        writeln!(out)?;
+        writeln!(out, "    unsafe fn as_raw(&self) -> *const u8 {{")?;
+        writeln!(out, "        self.raw")?;
+        writeln!(out, "    }}")?;
         writeln!(out, "}}")?;
 
         self.emit_debug_impl(out, reply_rs_typ, &reply.fields)?;

src/base.rs

@@ -311,6 +311,13 @@ pub trait Reply {
     /// The returned pointer must be freed with [`libc::free`] to avoid any memory leak, or be used
     /// to build another reply.
     unsafe fn into_raw(self) -> *const u8;
+
+    /// Get the raw pointer of the XCB reply.
+    ///
+    /// # Safety
+    /// The returned pointer must NOT be freed. Passing this pointer to [`libc::free`] will result in a double free
+    /// when the reply is dropped.
+    unsafe fn as_raw(&self) -> *const u8;
 }
 
 /// General trait for cookies returned by requests.