comparison rust/hg-core/src/repo.rs @ 49146:802e2c25dab8 stable

rust-dirstate-v2: clean up previous data file after the docket is written

This was overlooked before and caused many data files to keep living forever.
We could potentially consider adding a random cleanup of them in case they
slipped through one day.

Differential Revision: https://phab.mercurial-scm.org/D12581

49145:dd2503a63d33

    pub fn write_dirstate(&self) -> Result<(), DirstateError> {
        let map = self.dirstate_map()?;
        // TODO: Maintain a `DirstateMap::dirty` flag, and return early here if
        // it’s unset
        let parents = self.dirstate_parents()?;
        let packed_dirstate = if self.has_dirstate_v2() {
            let uuid = self.dirstate_data_file_uuid.get_or_init(self)?;
            let mut uuid = uuid.as_ref();
            let can_append = uuid.is_some();
            let (data, tree_metadata, append, old_data_size) =
                map.pack_v2(can_append)?;
            if !append {
                uuid = None
            }
            let uuid = if let Some(uuid) = uuid {
                std::str::from_utf8(uuid)
                    .map_err(|_| {
                        HgError::corrupted("non-UTF-8 dirstate data file ID")
                    })?
                    .to_owned()
            } else {
                DirstateDocket::new_uid()
            };
            let data_filename = format!("dirstate.{}", uuid);
            let data_filename = self.hg_vfs().join(data_filename);
            let mut options = std::fs::OpenOptions::new();
            if append {

                    // TODO: use https://doc.rust-lang.org/std/io/trait.Seek.html#method.stream_position when we require Rust 1.51+
                    file.seek(SeekFrom::Current(0))
                }
            })()
            .when_writing_file(&data_filename)?;
            DirstateDocket::serialize(
                parents,
                tree_metadata,
                data_size,
                uuid.as_bytes(),
            )
            .map_err(|_: std::num::TryFromIntError| {
                HgError::corrupted("overflow in dirstate docket serialization")
            })?
        } else {
            map.pack_v1(parents)?
        };
        self.hg_vfs().atomic_write("dirstate", &packed_dirstate)?;
        Ok(())
    }
}

/// Lazily-initialized component of `Repo` with interior mutability

49146:802e2c25dab8

    pub fn write_dirstate(&self) -> Result<(), DirstateError> {
        let map = self.dirstate_map()?;
        // TODO: Maintain a `DirstateMap::dirty` flag, and return early here if
        // it’s unset
        let parents = self.dirstate_parents()?;
        let (packed_dirstate, old_uuid_to_remove) = if self.has_dirstate_v2() {
            let uuid = self.dirstate_data_file_uuid.get_or_init(self)?;
            let mut uuid = uuid.as_ref();
            let can_append = uuid.is_some();
            let (data, tree_metadata, append, old_data_size) =
                map.pack_v2(can_append)?;
            if !append {
                uuid = None
            }
            let (uuid, old_uuid) = if let Some(uuid) = uuid {
                let as_str = std::str::from_utf8(uuid)
                    .map_err(|_| {
                        HgError::corrupted("non-UTF-8 dirstate data file ID")
                    })?
                    .to_owned();
                let old_uuid_to_remove = Some(as_str.to_owned());
                (as_str, old_uuid_to_remove)
            } else {
                (DirstateDocket::new_uid(), None)
            };
            let data_filename = format!("dirstate.{}", uuid);
            let data_filename = self.hg_vfs().join(data_filename);
            let mut options = std::fs::OpenOptions::new();
            if append {

                    // TODO: use https://doc.rust-lang.org/std/io/trait.Seek.html#method.stream_position when we require Rust 1.51+
                    file.seek(SeekFrom::Current(0))
                }
            })()
            .when_writing_file(&data_filename)?;

            let packed_dirstate = DirstateDocket::serialize(
                parents,
                tree_metadata,
                data_size,
                uuid.as_bytes(),
            )
            .map_err(|_: std::num::TryFromIntError| {
                HgError::corrupted("overflow in dirstate docket serialization")
            })?;

            (packed_dirstate, old_uuid)
        } else {
            (map.pack_v1(parents)?, None)
        };

        let vfs = self.hg_vfs();
        vfs.atomic_write("dirstate", &packed_dirstate)?;
        if let Some(uuid) = old_uuid_to_remove {
            // Remove the old data file after the new docket pointing to the
            // new data file was written.
            vfs.remove_file(format!("dirstate.{}", uuid))?;
        }
        Ok(())
    }
}

/// Lazily-initialized component of `Repo` with interior mutability