cleanup ignore_eof_error (#26838)

runtime/src/serde_snapshot/newer.rs

@@ -9,7 +9,7 @@ use {
         stakes::{serde_stakes_enum_compat, StakesEnum},
     },
     solana_measure::measure::Measure,
-    solana_sdk::stake::state::Delegation,
+    solana_sdk::{deserialize_utils::ignore_eof_error, stake::state::Delegation},
     std::{cell::RefCell, collections::HashSet, sync::RwLock},
 };
 
@@ -310,11 +310,7 @@ impl<'a> TypeContext<'a> for Context {
             deserialize_from::<_, DeserializableVersionedBank>(&mut stream)?.into();
         let accounts_db_fields = Self::deserialize_accounts_db_fields(stream)?;
         // Process extra fields
-        let lamports_per_signature: u64 = match deserialize_from(stream) {
-            Err(err) if err.to_string() == "io error: unexpected end of file" => Ok(0),
-            Err(err) if err.to_string() == "io error: failed to fill whole buffer" => Ok(0),
-            result => result,
-        }?;
+        let lamports_per_signature = ignore_eof_error(deserialize_from(&mut stream))?;
         bank_fields.fee_rate_governor = bank_fields
             .fee_rate_governor
             .clone_with_lamports_per_signature(lamports_per_signature);

sdk/src/deserialize_utils.rs

@@ -10,6 +10,14 @@ where
     T: Deserialize<'de> + Default,
 {
     let result = T::deserialize(d);
+    ignore_eof_error::<'de, T, D::Error>(result)
+}
+
+pub fn ignore_eof_error<'de, T, D>(result: Result<T, D>) -> Result<T, D>
+where
+    T: Deserialize<'de> + Default,
+    D: std::fmt::Display,
+{
     match result {
         Err(err) if err.to_string() == "io error: unexpected end of file" => Ok(T::default()),
         Err(err) if err.to_string() == "io error: failed to fill whole buffer" => Ok(T::default()),