diff options
Diffstat (limited to 'log_db/src/log_reader_forward.rs')
| -rw-r--r-- | log_db/src/log_reader_forward.rs | 53 |
1 files changed, 9 insertions, 44 deletions
diff --git a/log_db/src/log_reader_forward.rs b/log_db/src/log_reader_forward.rs index bfd329b..343d7ff 100644 --- a/log_db/src/log_reader_forward.rs +++ b/log_db/src/log_reader_forward.rs @@ -21,29 +21,7 @@ impl<'a> ForwardLogReader { ret } - pub fn new_with_index( - metadata_file: fs::File, - data_file: fs::File, - index: u64, - ) -> ForwardLogReader { - let mut ret = ForwardLogReader { - metadata_reader: io::BufReader::new(metadata_file), - data_reader: io::BufReader::new(data_file), - }; - - ret.metadata_reader - .seek(io::SeekFrom::Start( - METADATA_FILE_HEADER_SIZE as u64 + 16 * index, - )) - .expect("Seek failed"); - - ret - } - - fn read_record(&mut self) -> Result<Option<ForwardLogReaderItem>, io::Error> { - let metadata_index = - (self.metadata_reader.stream_position()? - METADATA_FILE_HEADER_SIZE as u64) / 16; - + fn read_record(&mut self) -> Result<Option<Record>, io::Error> { let mut metadata_entry_buf = vec![0; 16]; // 2x u64 if let Err(e) = self.metadata_reader.read_exact(&mut metadata_entry_buf) { if e.kind() == io::ErrorKind::UnexpectedEof { @@ -54,37 +32,24 @@ impl<'a> ForwardLogReader { } // First u64 is the offset of the record in the data file, second is the length of the record - let data_offset = u64::from_be_bytes(metadata_entry_buf[0..8].try_into().unwrap()); - let data_length = u64::from_be_bytes(metadata_entry_buf[8..16].try_into().unwrap()); + let entry_offset = u64::from_be_bytes(metadata_entry_buf[0..8].try_into().unwrap()); + let entry_length = u64::from_be_bytes(metadata_entry_buf[8..16].try_into().unwrap()); // Use .seek_relative instead of .seek to avoid dropping the BufReader internal buffer when // the seek distance is small - let seek_distance = data_offset - self.data_reader.stream_position()?; + let seek_distance = entry_offset - self.data_reader.stream_position()?; self.data_reader.seek_relative(seek_distance as i64)?; - let mut result_buf = vec![0; data_length as usize]; + let mut result_buf = vec![0; entry_length as usize]; self.data_reader.read_exact(&mut result_buf)?; let record = Record::deserialize(&result_buf); - let item = ForwardLogReaderItem { - metadata_index, - data_offset, - data_length, - record, - }; - Ok(Some(item)) + Ok(Some(record)) } } -pub struct ForwardLogReaderItem { - pub metadata_index: u64, - pub data_offset: u64, - pub data_length: u64, - pub record: Record, -} - impl Iterator for ForwardLogReader { - type Item = ForwardLogReaderItem; + type Item = Record; fn next(&mut self) -> Option<Self::Item> { match self.read_record() { @@ -118,10 +83,10 @@ mod tests { // There are two records in the log with "schema" with one field: Bytes - let first_item = forward_log_reader + let first_record = forward_log_reader .next() .expect("Failed to read the first record"); - assert!(match first_item.record.values() { + assert!(match first_record.values() { [Value::Bytes(bytes)] => bytes.len() == 256, _ => false, }); |
