better fix

Author: mrain

hotshot-types/src/data/ns_table.rs

@@ -26,14 +26,18 @@ pub fn parse_ns_table(payload_byte_len: usize, bytes: &[u8]) -> Vec<Range<usize>
         return vec![(0..payload_byte_len)];
     }
     let num_entries = u32::from_le_bytes(bytes[..NUM_NSS_BYTE_LEN].try_into().unwrap()) as usize;
-    if num_entries == 0
-        || num_entries
-            != bytes.len().saturating_sub(NUM_NSS_BYTE_LEN)
-                / NS_ID_BYTE_LEN.saturating_add(NS_OFFSET_BYTE_LEN)
+    if num_entries
+        != bytes.len().saturating_sub(NUM_NSS_BYTE_LEN)
+            / NS_ID_BYTE_LEN.saturating_add(NS_OFFSET_BYTE_LEN)
+        || (num_entries == 0 && payload_byte_len != 0)
     {
         tracing::warn!("Failed to parse the metadata as namespace table. Use a single namespace table instead.");
         return vec![(0..payload_byte_len)];
     }
+    // Early breaks for empty payload and namespae table
+    if num_entries == 0 {
+        return vec![(0..payload_byte_len)];
+    }
     let mut l = 0;
     for i in 0..num_entries {
         let offset = NUM_NSS_BYTE_LEN + i * (NS_ID_BYTE_LEN + NS_OFFSET_BYTE_LEN) + NS_ID_BYTE_LEN;