umskt/src/confid/mod.rs

@@ -1,3 +1,5 @@
+use std::ffi::{CStr, CString};
+
 use thiserror::Error;
 
 mod black_box;
@@ -25,9 +27,9 @@ pub fn generate(installation_id: &str) -> Result<String, ConfirmationIdError> {
     if installation_id.len() > 54 {
         return Err(ConfirmationIdError::TooLarge);
     }
-    let inst_id = installation_id.as_bytes();
-    let mut conf_id = [0u8; 48];
-    let result = black_box::generate(inst_id, &mut conf_id);
+    let inst_id = CString::new(installation_id).unwrap();
+    let conf_id = [0u8; 49];
+    let result = unsafe { black_box::generate(inst_id.as_ptr(), conf_id.as_ptr() as *mut i8) };
     match result {
         0 => {}
         1 => return Err(ConfirmationIdError::TooShort),
@@ -38,7 +40,12 @@ pub fn generate(installation_id: &str) -> Result<String, ConfirmationIdError> {
         6 => return Err(ConfirmationIdError::Unlucky),
         _ => panic!("Unknown error code: {}", result),
     }
-    Ok(String::from_utf8_lossy(&conf_id).into())
+    unsafe {
+        Ok(CStr::from_ptr(conf_id.as_ptr() as *const i8)
+            .to_str()
+            .unwrap()
+            .to_string())
+    }
 }
 
 #[cfg(test)]