- int roundtrip = last_missing;
- while (chunks[last_missing]) {
- ++last_missing;
- last_missing %= total_length;
- if (last_missing == roundtrip) {
- break;
+ if (MissingChunks() > 0) {
+ int roundtrip = last_missing;
+ last_missing = (last_missing + 1) % total_length;
+ while (chunks[last_missing]) {
+ last_missing = (last_missing + 1) % total_length;
+ if (last_missing == roundtrip) {
+ break;
+ }