Struct git_pack::data::input::LookupRefDeltaObjectsIter

pub struct LookupRefDeltaObjectsIter<I, LFn> {
    pub inner: I,
    /* private fields */
}

An iterator to resolve thin packs on the fly.

Fields

inner: I

The inner iterator whose entries we will resolve.

Implementations

impl<I, LFn> LookupRefDeltaObjectsIter<I, LFn>where
    I: Iterator<Item = Result<Entry, Error>>,
    LFn: for<'a> FnMut(ObjectId, &'a mut Vec<u8>) -> Option<Data<'a>>,

pub fn new(iter: I, lookup: LFn) -> Self

Create a new instance wrapping iter and using lookup as function to retrieve objects that will serve as bases for ref deltas seen while traversing iter.

Examples found in repository

src/bundle/write/mod.rs (lines 78-86)

    pub fn write_to_directory<P>(
        pack: impl io::BufRead,
        directory: Option<impl AsRef<Path>>,
        mut progress: P,
        should_interrupt: &AtomicBool,
        thin_pack_base_object_lookup_fn: Option<ThinPackLookupFn>,
        options: Options,
    ) -> Result<Outcome, Error>
    where
        P: Progress,
    {
        let mut read_progress = progress.add_child_with_id("read pack", *b"BWRB"); /* Bundle Write Read pack Bytes*/
        read_progress.init(None, progress::bytes());
        let pack = progress::Read {
            inner: pack,
            progress: progress::ThroughputOnDrop::new(read_progress),
        };

        let object_hash = options.object_hash;
        let data_file = Arc::new(parking_lot::Mutex::new(io::BufWriter::with_capacity(
            64 * 1024,
            match directory.as_ref() {
                Some(directory) => git_tempfile::new(directory, ContainingDirectory::Exists, AutoRemove::Tempfile)?,
                None => git_tempfile::new(std::env::temp_dir(), ContainingDirectory::Exists, AutoRemove::Tempfile)?,
            },
        )));
        let (pack_entries_iter, pack_version): (
            Box<dyn Iterator<Item = Result<data::input::Entry, data::input::Error>>>,
            _,
        ) = match thin_pack_base_object_lookup_fn {
            Some(thin_pack_lookup_fn) => {
                let pack = interrupt::Read {
                    inner: pack,
                    should_interrupt,
                };
                let buffered_pack = io::BufReader::new(pack);
                let pack_entries_iter = data::input::LookupRefDeltaObjectsIter::new(
                    data::input::BytesToEntriesIter::new_from_header(
                        buffered_pack,
                        options.iteration_mode,
                        data::input::EntryDataMode::KeepAndCrc32,
                        object_hash,
                    )?,
                    thin_pack_lookup_fn,
                );
                let pack_version = pack_entries_iter.inner.version();
                let pack_entries_iter = data::input::EntriesToBytesIter::new(
                    pack_entries_iter,
                    LockWriter {
                        writer: data_file.clone(),
                    },
                    pack_version,
                    git_hash::Kind::Sha1, // Thin packs imply a pack being transported, and there we only ever know SHA1 at the moment.
                );
                (Box::new(pack_entries_iter), pack_version)
            }
            None => {
                let pack = PassThrough {
                    reader: interrupt::Read {
                        inner: pack,
                        should_interrupt,
                    },
                    writer: Some(data_file.clone()),
                };
                // This buf-reader is required to assure we call 'read()' in order to fill the (extra) buffer. Otherwise all the counting
                // we do with the wrapped pack reader doesn't work as it does not expect anyone to call BufRead functions directly.
                // However, this is exactly what's happening in the ZipReader implementation that is eventually used.
                // The performance impact of this is probably negligible, compared to all the other work that is done anyway :D.
                let buffered_pack = io::BufReader::new(pack);
                let pack_entries_iter = data::input::BytesToEntriesIter::new_from_header(
                    buffered_pack,
                    options.iteration_mode,
                    data::input::EntryDataMode::Crc32,
                    object_hash,
                )?;
                let pack_version = pack_entries_iter.version();
                (Box::new(pack_entries_iter), pack_version)
            }
        };
        let WriteOutcome {
            outcome,
            data_path,
            index_path,
            keep_path,
        } = crate::Bundle::inner_write(
            directory,
            progress,
            options,
            data_file,
            pack_entries_iter,
            should_interrupt,
            pack_version,
        )?;

        Ok(Outcome {
            index: outcome,
            object_hash,
            pack_version,
            data_path,
            index_path,
            keep_path,
        })
    }

    /// Equivalent to [`write_to_directory()`][crate::Bundle::write_to_directory()] but offloads reading of the pack into its own thread, hence the `Send + 'static'` bounds.
    ///
    /// # Note
    ///
    /// As it sends portions of the input to a thread it requires the 'static lifetime for the interrupt flags. This can only
    /// be satisfied by a static AtomicBool which is only suitable for programs that only run one of these operations at a time
    /// or don't mind that all of them abort when the flag is set.
    pub fn write_to_directory_eagerly<P>(
        pack: impl io::Read + Send + 'static,
        pack_size: Option<u64>,
        directory: Option<impl AsRef<Path>>,
        mut progress: P,
        should_interrupt: &'static AtomicBool,
        thin_pack_base_object_lookup_fn: Option<ThinPackLookupFnSend>,
        options: Options,
    ) -> Result<Outcome, Error>
    where
        P: Progress,
        P::SubProgress: 'static,
    {
        let mut read_progress = progress.add_child_with_id("read pack", *b"BWRB"); /* Bundle Write Read pack Bytes*/
        read_progress.init(pack_size.map(|s| s as usize), progress::bytes());
        let pack = progress::Read {
            inner: pack,
            progress: progress::ThroughputOnDrop::new(read_progress),
        };

        let data_file = Arc::new(parking_lot::Mutex::new(io::BufWriter::new(match directory.as_ref() {
            Some(directory) => git_tempfile::new(directory, ContainingDirectory::Exists, AutoRemove::Tempfile)?,
            None => git_tempfile::new(std::env::temp_dir(), ContainingDirectory::Exists, AutoRemove::Tempfile)?,
        })));
        let object_hash = options.object_hash;
        let eight_pages = 4096 * 8;
        let (pack_entries_iter, pack_version): (
            Box<dyn Iterator<Item = Result<data::input::Entry, data::input::Error>> + Send + 'static>,
            _,
        ) = match thin_pack_base_object_lookup_fn {
            Some(thin_pack_lookup_fn) => {
                let pack = interrupt::Read {
                    inner: pack,
                    should_interrupt,
                };
                let buffered_pack = io::BufReader::with_capacity(eight_pages, pack);
                let pack_entries_iter = data::input::LookupRefDeltaObjectsIter::new(
                    data::input::BytesToEntriesIter::new_from_header(
                        buffered_pack,
                        options.iteration_mode,
                        data::input::EntryDataMode::KeepAndCrc32,
                        object_hash,
                    )?,
                    thin_pack_lookup_fn,
                );
                let pack_kind = pack_entries_iter.inner.version();
                (Box::new(pack_entries_iter), pack_kind)
            }
            None => {
                let pack = PassThrough {
                    reader: interrupt::Read {
                        inner: pack,
                        should_interrupt,
                    },
                    writer: Some(data_file.clone()),
                };
                let buffered_pack = io::BufReader::with_capacity(eight_pages, pack);
                let pack_entries_iter = data::input::BytesToEntriesIter::new_from_header(
                    buffered_pack,
                    options.iteration_mode,
                    data::input::EntryDataMode::Crc32,
                    object_hash,
                )?;
                let pack_kind = pack_entries_iter.version();
                (Box::new(pack_entries_iter), pack_kind)
            }
        };
        let num_objects = pack_entries_iter.size_hint().0;
        let pack_entries_iter =
            git_features::parallel::EagerIterIf::new(move || num_objects > 25_000, pack_entries_iter, 5_000, 5);

        let WriteOutcome {
            outcome,
            data_path,
            index_path,
            keep_path,
        } = crate::Bundle::inner_write(
            directory,
            progress,
            options,
            data_file,
            pack_entries_iter,
            should_interrupt,
            pack_version,
        )?;

        Ok(Outcome {
            index: outcome,
            object_hash,
            pack_version,
            data_path,
            index_path,
            keep_path,
        })
    }

Trait Implementations

impl<I, LFn> Iterator for LookupRefDeltaObjectsIter<I, LFn>where
    I: Iterator<Item = Result<Entry, Error>>,
    LFn: for<'a> FnMut(ObjectId, &'a mut Vec<u8>) -> Option<Data<'a>>,

type Item = Result<Entry, Error>

The type of the elements being iterated over.

fn next(&mut self) -> Option<Self::Item>

Advances the iterator and returns the next value.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the iterator.

fn next_chunk<const N: usize>(
    &mut self
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
    Self: Sized,

🔬This is a nightly-only experimental API. (iter_next_chunk)

Advances the iterator and returns an array containing the next N values.

fn count(self) -> usizewhere
    Self: Sized,

Consumes the iterator, counting the number of iterations and returning it.

fn last(self) -> Option<Self::Item>where
    Self: Sized,

Consumes the iterator, returning the last element.

fn advance_by(&mut self, n: usize) -> Result<(), usize>

🔬This is a nightly-only experimental API. (iter_advance_by)

Advances the iterator by n elements.

fn nth(&mut self, n: usize) -> Option<Self::Item>

Returns the nth element of the iterator.

fn step_by(self, step: usize) -> StepBy<Self>where
    Self: Sized,

Creates an iterator starting at the same point, but stepping by the given amount at each iteration.

fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>where
    Self: Sized,
    U: IntoIterator<Item = Self::Item>,

Takes two iterators and creates a new iterator over both in sequence.

fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>where
    Self: Sized,
    U: IntoIterator,

‘Zips up’ two iterators into a single iterator of pairs.

fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>where
    Self: Sized,
    G: FnMut() -> Self::Item,

🔬This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator.

fn map<B, F>(self, f: F) -> Map<Self, F>where
    Self: Sized,
    F: FnMut(Self::Item) -> B,

Takes a closure and creates an iterator which calls that closure on each element.

fn for_each<F>(self, f: F)where
    Self: Sized,
    F: FnMut(Self::Item),

Calls a closure on each element of an iterator.

fn filter<P>(self, predicate: P) -> Filter<Self, P>where
    Self: Sized,
    P: FnMut(&Self::Item) -> bool,

Creates an iterator which uses a closure to determine if an element should be yielded.

fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>where
    Self: Sized,
    F: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both filters and maps.

fn enumerate(self) -> Enumerate<Self>where
    Self: Sized,

Creates an iterator which gives the current iteration count as well as the next value.

fn peekable(self) -> Peekable<Self>where
    Self: Sized,

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information.

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>where
    Self: Sized,
    P: FnMut(&Self::Item) -> bool,

Creates an iterator that skips elements based on a predicate.

fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>where
    Self: Sized,
    P: FnMut(&Self::Item) -> bool,

Creates an iterator that yields elements based on a predicate.

fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>where
    Self: Sized,
    P: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both yields elements based on a predicate and maps.

fn skip(self, n: usize) -> Skip<Self>where
    Self: Sized,

Creates an iterator that skips the first n elements.

fn take(self, n: usize) -> Take<Self>where
    Self: Sized,

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner.

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F>where
    Self: Sized,
    F: FnMut(&mut St, Self::Item) -> Option<B>,

An iterator adapter similar to fold that holds internal state and produces a new iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>where
    Self: Sized,
    U: IntoIterator,
    F: FnMut(Self::Item) -> U,

Creates an iterator that works like map, but flattens nested structure.

fn fuse(self) -> Fuse<Self>where
    Self: Sized,

Creates an iterator which ends after the first None.

fn inspect<F>(self, f: F) -> Inspect<Self, F>where
    Self: Sized,
    F: FnMut(&Self::Item),

Does something with each element of an iterator, passing the value on.

fn by_ref(&mut self) -> &mut Selfwhere
    Self: Sized,

Borrows an iterator, rather than consuming it.

fn collect<B>(self) -> Bwhere
    B: FromIterator<Self::Item>,
    Self: Sized,

Transforms an iterator into a collection.

fn collect_into<E>(self, collection: &mut E) -> &mut Ewhere
    E: Extend<Self::Item>,
    Self: Sized,

🔬This is a nightly-only experimental API. (iter_collect_into)

Collects all the items from an iterator into a collection.

fn partition<B, F>(self, f: F) -> (B, B)where
    Self: Sized,
    B: Default + Extend<Self::Item>,
    F: FnMut(&Self::Item) -> bool,

Consumes an iterator, creating two collections from it.

fn is_partitioned<P>(self, predicate: P) -> boolwhere
    Self: Sized,
    P: FnMut(Self::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_is_partitioned)

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false.

fn try_fold<B, F, R>(&mut self, init: B, f: F) -> Rwhere
    Self: Sized,
    F: FnMut(B, Self::Item) -> R,
    R: Try<Output = B>,

An iterator method that applies a function as long as it returns successfully, producing a single, final value.

fn try_for_each<F, R>(&mut self, f: F) -> Rwhere
    Self: Sized,
    F: FnMut(Self::Item) -> R,
    R: Try<Output = ()>,

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error.

fn fold<B, F>(self, init: B, f: F) -> Bwhere
    Self: Sized,
    F: FnMut(B, Self::Item) -> B,

Folds every element into an accumulator by applying an operation, returning the final result.

fn reduce<F>(self, f: F) -> Option<Self::Item>where
    Self: Sized,
    F: FnMut(Self::Item, Self::Item) -> Self::Item,

Reduces the elements to a single one, by repeatedly applying a reducing operation.

fn try_reduce<F, R>(
    &mut self,
    f: F
) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryTypewhere
    Self: Sized,
    F: FnMut(Self::Item, Self::Item) -> R,
    R: Try<Output = Self::Item>,
    <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (iterator_try_reduce)

Reduces the elements to a single one by repeatedly applying a reducing operation. If the closure returns a failure, the failure is propagated back to the caller immediately.

fn all<F>(&mut self, f: F) -> boolwhere
    Self: Sized,
    F: FnMut(Self::Item) -> bool,

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> boolwhere
    Self: Sized,
    F: FnMut(Self::Item) -> bool,

Tests if any element of the iterator matches a predicate.

fn find<P>(&mut self, predicate: P) -> Option<Self::Item>where
    Self: Sized,
    P: FnMut(&Self::Item) -> bool,

Searches for an element of an iterator that satisfies a predicate.

fn find_map<B, F>(&mut self, f: F) -> Option<B>where
    Self: Sized,
    F: FnMut(Self::Item) -> Option<B>,

Applies function to the elements of iterator and returns the first non-none result.

fn try_find<F, R>(
    &mut self,
    f: F
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryTypewhere
    Self: Sized,
    F: FnMut(&Self::Item) -> R,
    R: Try<Output = bool>,
    <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (try_find)

Applies function to the elements of iterator and returns the first true result or the first error.

fn position<P>(&mut self, predicate: P) -> Option<usize>where
    Self: Sized,
    P: FnMut(Self::Item) -> bool,

Searches for an element in an iterator, returning its index.

fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>where
    B: Ord,
    Self: Sized,
    F: FnMut(&Self::Item) -> B,

Returns the element that gives the maximum value from the specified function.

fn max_by<F>(self, compare: F) -> Option<Self::Item>where
    Self: Sized,
    F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the maximum value with respect to the specified comparison function.

fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>where
    B: Ord,
    Self: Sized,
    F: FnMut(&Self::Item) -> B,

Returns the element that gives the minimum value from the specified function.

fn min_by<F>(self, compare: F) -> Option<Self::Item>where
    Self: Sized,
    F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the minimum value with respect to the specified comparison function.

fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)where
    FromA: Default + Extend<A>,
    FromB: Default + Extend<B>,
    Self: Sized + Iterator<Item = (A, B)>,

Converts an iterator of pairs into a pair of containers.

fn copied<'a, T>(self) -> Copied<Self>where
    T: 'a + Copy,
    Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which copies all of its elements.

fn cloned<'a, T>(self) -> Cloned<Self>where
    T: 'a + Clone,
    Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which clones all of its elements.

fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>where
    Self: Sized,

🔬This is a nightly-only experimental API. (iter_array_chunks)

Returns an iterator over N elements of the iterator at a time.

fn sum<S>(self) -> Swhere
    Self: Sized,
    S: Sum<Self::Item>,

Sums the elements of an iterator.

fn product<P>(self) -> Pwhere
    Self: Sized,
    P: Product<Self::Item>,

Iterates over the entire iterator, multiplying all the elements

fn cmp_by<I, F>(self, other: I, cmp: F) -> Orderingwhere
    Self: Sized,
    I: IntoIterator,
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn partial_cmp<I>(self, other: I) -> Option<Ordering>where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

Lexicographically compares the elements of this Iterator with those of another.

fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>where
    Self: Sized,
    I: IntoIterator,
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn eq<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>,
    Self: Sized,

Determines if the elements of this Iterator are equal to those of another.

fn eq_by<I, F>(self, other: I, eq: F) -> boolwhere
    Self: Sized,
    I: IntoIterator,
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_order_by)

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function.

fn ne<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>,
    Self: Sized,

Determines if the elements of this Iterator are unequal to those of another.

fn lt<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

Determines if the elements of this Iterator are lexicographically less than those of another.

fn le<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

Determines if the elements of this Iterator are lexicographically less or equal to those of another.

fn gt<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than those of another.

fn ge<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another.

fn is_sorted_by<F>(self, compare: F) -> boolwhere
    Self: Sized,
    F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>,

🔬This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this iterator are sorted using the given comparator function.

fn is_sorted_by_key<F, K>(self, f: F) -> boolwhere
    Self: Sized,
    F: FnMut(Self::Item) -> K,
    K: PartialOrd<K>,

🔬This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this iterator are sorted using the given key extraction function.