Method truncate

crates/commitlog/src/index/indexfile.rs:212–249

Truncates the index file starting from the entry with a key greater than or equal to the given key. If successful, `key` will no longer be in the index.

(&mut self, key: Key)

    ///
    /// If successful, `key` will no longer be in the index.
    pub(crate) fn truncate(&mut self, key: Key) -> Result<(), IndexError> {
        let key = key.into();
        let (found_key, index) = self
            .find_index(Key::from(key))
            .map(|(found, index)| (found.into(), index))
            .or_else(|e| {
                match e {
                    // If key is smaller than first entry, truncate all entries
                    IndexError::KeyNotFound => Ok((key, 0)),
                    _ => Err(e),
                }
            })?;

        // If returned key is smaller than asked key, truncate from next entry
        self.num_entries = if found_key == key {
            index as usize
        } else {
            index as usize + 1
        };

        let start = self.num_entries * ENTRY_SIZE;
        trace!(
            "truncate key={} found={} index={} num-entries={} start={}",
            key,
            found_key,
            index,
            self.num_entries,
            start
        );

        if start < self.inner.len() {
            self.inner[start..].fill(0);
        }

        self.inner.flush()?;

        Ok(())
    }

    /// Obtain an iterator over the entries of the index.
    pub fn entries(&self) -> Entries<'_, Key> {