more idiomatic current_time determination

rust/src/main.rs

@@ -242,23 +242,15 @@ fn safe_main() -> anyhow::Result<()> {
     log(log::LogMessage::FilesystemMount, free_space.free_size as u32,
         free_space.total_size as u32, &free_space.used_size.to_string(), "");
 
-
+    let mut cur = board.get_rtc_time().or_else(|err| {
-    let mut cur = match board.get_rtc_time() {
+        println!("rtc module error: {:?}", err);
-        Ok(time) => time,
-        Err(err) => {
-            println!("rtc module error: {}", err);
         board.general_fault(true);
-            let time = board.time();
+        board.time()
-            match time {
+    }).map_err(|err| -> Result<(), _>{
-                Ok(cur) => cur,
-                Err(err) => {
         bail!("time error {}", err);
-                }
+    }).unwrap();
-            }
-        }
-    };
 
-    //check if we know the time current > 2020
+    //check if we know the time current > 2020 (plausibility check, this code is newer than 2020)
     if cur.year() < 2020 {
         to_config = true;
         log(log::LogMessage::YearInplausibleForceConfig, 0,0,"","");
@@ -988,7 +980,7 @@ fn main() {
         // if safe_main exists with error, rollback to known good ota version
         Err(err) => {
             println!("Failed main {}", err);
-            let rollback_successful = rollback_and_reboot();
+            let _rollback_successful = rollback_and_reboot();
             panic!("Failed to rollback :(");
         }
     }