Sebastian Thieldocs for Bundle::write_*ac412536 years agoHistory
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use filebuffer::FileBuffer; use crate::pack;use git_features::{interrupt, progress, progress::Progress};use std::{    io,    path::{Path, PathBuf},    sync::Arc,};use tempfile::NamedTempFile; mod error;use error::Error; mod types;use types::PassThrough;pub use types::{Options, Outcome}; impl pack::Bundle {    /// Given a `pack` data stream into the `directory` if `Some` or discard it entirely if `None`.    ///    /// `progress` provides detailed progress information which can be discarded with [`git_features::progress::Discard`].    /// `options` further configure how the task is performed.    pub fn write_stream_to_directory(        pack: impl io::BufRead,        directory: Option<impl AsRef<Path>>,        mut progress: impl Progress,        options: Options,    ) -> Result<Outcome, Error> {        let mut read_progress = progress.add_child("read pack");        read_progress.init(None, progress::bytes());        let pack = progress::Read {            reader: pack,            progress: progress::ThroughputOnDrop::new(read_progress),        };         let data_file = Arc::new(parking_lot::Mutex::new(match directory.as_ref() {            Some(directory) => NamedTempFile::new_in(directory.as_ref())?,            None => NamedTempFile::new()?,        }));        let data_path: PathBuf = data_file.lock().path().into();        let pack = PassThrough {            reader: interrupt::Read { inner: pack },            writer: Some(data_file.clone()),        };        // This buff-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 = pack::data::Iter::new_from_header(            buffered_pack,            options.iteration_mode,            pack::data::iter::CompressedBytesMode::CRC32,        )?;        let pack_kind = pack_entries_iter.kind();        let (outcome, data_path, index_path) =            pack::Bundle::inner_write(directory, progress, options, data_file, data_path, pack_entries_iter)?;         Ok(Outcome {            index: outcome,            pack_kind,            data_path,            index_path,        })    }     /// Equivalent to [`write_stream_to_directory()`][pack::Bundle::write_stream_to_directory()] but offloads reading of the pack into its own thread, hence the `Send + 'static'` bounds.    pub fn write_to_directory_eagerly(        pack: impl io::Read + Send + 'static,        pack_size: Option<u64>,        directory: Option<impl AsRef<Path>>,        mut progress: impl Progress,        options: Options,    ) -> Result<Outcome, Error> {        let mut read_progress = progress.add_child("read pack");        read_progress.init(pack_size.map(|s| s as usize), progress::bytes());        let pack = progress::Read {            reader: pack,            progress: progress::ThroughputOnDrop::new(read_progress),        };         let data_file = Arc::new(parking_lot::Mutex::new(match directory.as_ref() {            Some(directory) => NamedTempFile::new_in(directory.as_ref())?,            None => NamedTempFile::new()?,        }));        let data_path: PathBuf = data_file.lock().path().into();        let pack = PassThrough {            reader: interrupt::Read { inner: pack },            writer: Some(data_file.clone()),        };        let eight_pages = 4096 * 8;        let buffered_pack = io::BufReader::with_capacity(eight_pages, pack);        let pack_entries_iter = pack::data::Iter::new_from_header(            buffered_pack,            options.iteration_mode,            pack::data::iter::CompressedBytesMode::CRC32,        )?;        let pack_kind = pack_entries_iter.kind();        let num_objects = pack_entries_iter.size_hint().0;        let pack_entries_iter =            git_features::parallel::EagerIterIf::new(|| num_objects > 25_000, pack_entries_iter, 5_000, 5);         let (outcome, data_path, index_path) =            pack::Bundle::inner_write(directory, progress, options, data_file, data_path, pack_entries_iter)?;         Ok(Outcome {            index: outcome,            pack_kind,            data_path,            index_path,        })    }     fn inner_write(        directory: Option<impl AsRef<Path>>,        mut progress: impl Progress,        Options {            thread_limit,            iteration_mode: _,            index_kind,        }: Options,        data_file: Arc<parking_lot::Mutex<NamedTempFile>>,        data_path: PathBuf,        pack_entries_iter: impl Iterator<Item = Result<pack::data::iter::Entry, pack::data::iter::Error>>,    ) -> Result<(pack::index::write::Outcome, Option<PathBuf>, Option<PathBuf>), Error> {        let indexing_progress = progress.add_child("create index file");        Ok(match directory {            Some(directory) => {                let directory = directory.as_ref();                let mut index_file = NamedTempFile::new_in(directory)?;                 let outcome = pack::index::File::write_data_iter_to_stream(                    index_kind,                    move || new_pack_file_resolver(data_path),                    pack_entries_iter,                    thread_limit,                    indexing_progress,                    &mut index_file,                )?;                 let data_path = directory.join(format!("{}.pack", outcome.data_hash.to_sha1_hex_string()));                let index_path = data_path.with_extension("idx");                 Arc::try_unwrap(data_file)                    .expect("only one handle left after pack was consumed")                    .into_inner()                    .persist(&data_path)?;                index_file                    .persist(&index_path)                    .map_err(|err| {                        progress.info(format!(                            "pack file at {} is retained despite failing to move the index file into place. You can use plumbing to make it usable.",                            data_path.display()                        ));                        err                    })?;                (outcome, Some(data_path), Some(index_path))            }            None => (                pack::index::File::write_data_iter_to_stream(                    index_kind,                    move || new_pack_file_resolver(data_path),                    pack_entries_iter,                    thread_limit,                    indexing_progress,                    io::sink(),                )?,                None,                None,            ),        })    }} fn new_pack_file_resolver(    data_path: PathBuf,) -> io::Result<impl Fn(pack::data::EntrySlice, &mut Vec<u8>) -> Option<()> + Send + Sync> {    let mapped_file = FileBuffer::open(data_path)?;    let pack_data_lookup = move |range: std::ops::Range<u64>, out: &mut Vec<u8>| -> Option<()> {        mapped_file            .get(range.start as usize..range.end as usize)            .map(|pack_entry| out.copy_from_slice(pack_entry))    };    Ok(pack_data_lookup)}