case kEof:
if (in_fragmented_record) {
- ReportCorruption(scratch->size(), "partial record without end(3)");
+ // This can be caused by the writer dying immediately after
+ // writing a physical record but before completing the next; don't
+ // treat it as a corruption, just ignore the entire logical record.
scratch->clear();
}
return false;
eof_ = true;
}
continue;
- } else if (buffer_.size() == 0) {
- // End of file
- return kEof;
} else {
- size_t drop_size = buffer_.size();
+ // Note that if buffer_ is non-empty, we have a truncated header at the
+ // end of the file, which can be caused by the writer crashing in the
+ // middle of writing the header. Instead of considering this an error,
+ // just report EOF.
buffer_.clear();
- ReportCorruption(drop_size, "truncated record at end of file");
return kEof;
}
}
if (kHeaderSize + length > buffer_.size()) {
size_t drop_size = buffer_.size();
buffer_.clear();
- ReportCorruption(drop_size, "bad record length");
- return kBadRecord;
+ if (!eof_) {
+ ReportCorruption(drop_size, "bad record length");
+ return kBadRecord;
+ }
+ // If the end of the file has been reached without reading |length| bytes
+ // of payload, assume the writer died in the middle of writing the record.
+ // Don't report a corruption.
+ return kEof;
}
if (type == kZeroType && length == 0) {
ASSERT_EQ("OK", MatchError("unknown record type"));
}
-TEST(LogTest, TruncatedTrailingRecord) {
+TEST(LogTest, TruncatedTrailingRecordIsIgnored) {
Write("foo");
ShrinkSize(4); // Drop all payload as well as a header byte
ASSERT_EQ("EOF", Read());
- ASSERT_EQ(kHeaderSize - 1, DroppedBytes());
- ASSERT_EQ("OK", MatchError("truncated record at end of file"));
+ // Truncated last record is ignored, not treated as an error.
+ ASSERT_EQ(0, DroppedBytes());
+ ASSERT_EQ("", ReportMessage());
}
TEST(LogTest, BadLength) {
+ const int kPayloadSize = kBlockSize - kHeaderSize;
+ Write(BigString("bar", kPayloadSize));
+ Write("foo");
+ // Least significant size byte is stored in header[4].
+ IncrementByte(4, 1);
+ ASSERT_EQ("foo", Read());
+ ASSERT_EQ(kBlockSize, DroppedBytes());
+ ASSERT_EQ("OK", MatchError("bad record length"));
+}
+
+TEST(LogTest, BadLengthAtEndIsIgnored) {
Write("foo");
ShrinkSize(1);
ASSERT_EQ("EOF", Read());
- ASSERT_EQ(kHeaderSize + 2, DroppedBytes());
- ASSERT_EQ("OK", MatchError("bad record length"));
+ ASSERT_EQ(0, DroppedBytes());
+ ASSERT_EQ("", ReportMessage());
}
TEST(LogTest, ChecksumMismatch) {
ASSERT_EQ("OK", MatchError("partial record without end"));
}
+TEST(LogTest, MissingLastIsIgnored) {
+ Write(BigString("bar", kBlockSize));
+ // Remove the LAST block, including header.
+ ShrinkSize(14);
+ ASSERT_EQ("EOF", Read());
+ ASSERT_EQ("", ReportMessage());
+ ASSERT_EQ(0, DroppedBytes());
+}
+
+TEST(LogTest, PartialLastIsIgnored) {
+ Write(BigString("bar", kBlockSize));
+ // Cause a bad record length in the LAST block.
+ ShrinkSize(1);
+ ASSERT_EQ("EOF", Read());
+ ASSERT_EQ("", ReportMessage());
+ ASSERT_EQ(0, DroppedBytes());
+}
+
TEST(LogTest, ErrorJoinsRecords) {
// Consider two fragmented records:
// first(R1) last(R1) first(R2) last(R2)