add get_aux_string function

libnyx/src/ffi.rs

@@ -202,4 +202,18 @@ pub extern "C" fn nyx_print_aux_buffer(nyx_process: * mut NyxProcess) {
             _ => {},
         }
     }
-}
+}
+
+#[no_mangle]
+pub extern "C" fn nyx_get_aux_string(nyx_process: * mut NyxProcess, buffer: *mut u8, size: u32) -> u32 {
+
+    unsafe{
+        assert!(!nyx_process.is_null());
+        assert!((nyx_process as usize) % std::mem::align_of::<NyxProcess>() == 0);
+        assert!((buffer as usize) % std::mem::align_of::<u8>() == 0);
+
+        let len = std::cmp::min( (*nyx_process).process.aux.misc.len as usize, size as usize);
+        std::ptr::copy((*nyx_process).process.aux.misc.data.as_mut_ptr(), buffer, len);
+        len as u32
+    }
+}

libnyx/src/lib.rs

@@ -254,7 +254,12 @@ impl NyxProcess {
     pub fn aux_tmp_snapshot_created(&self) -> bool {
         self.process.aux.result.tmp_snapshot_created != 0
     }
-    
+
+    pub fn aux_string(&self) -> String {
+        let len = self.process.aux.misc.len;
+        String::from_utf8_lossy(&self.process.aux.misc.data[0..len as usize]).to_string()
+    }
+     
     pub fn exec(&mut self) -> NyxReturnValue {
         match self.process.send_payload(){
             Err(_) =>  NyxReturnValue::IoError,