comparison rust/hg-core/src/revlog/index.rs @ 51233:ca81cd96000a

rust-index: add Sync bound to all relevant mmap-derived values

All readonly mmaps are Sync as far as Rust is concerned. Integrity of the
mmap'ed file is a concern separate to Rust's memory model, since it requires
out-of-program handling via locks, etc.

This will help when we start sharing the Rust Index with Python.

51232:3551f2a1c963

/// Abstracts the access to the index bytes since they can be spread between
/// the immutable (bytes) part and the mutable (added) part if any appends
/// happened. This makes it transparent for the callers.
struct IndexData {
    /// Immutable bytes, most likely taken from disk
    bytes: Box<dyn Deref<Target = [u8]> + Send>,
    /// Used when stripping index contents, keeps track of the start of the
    /// first stripped revision, which is used to give a slice of the
    /// `bytes` field.
    truncation: Option<usize>,
    /// Bytes that were added after reading the index
    added: Vec<u8>,
}

impl IndexData {
    pub fn new(bytes: Box<dyn Deref<Target = [u8]> + Send>) -> Self {
        Self {
            bytes,
            truncation: None,
            added: vec![],
        }

impl Index {
    /// Create an index from bytes.
    /// Calculate the start of each entry when is_inline is true.
    pub fn new(
        bytes: Box<dyn Deref<Target = [u8]> + Send>,
        default_header: IndexHeader,
    ) -> Result<Self, HgError> {
        let header =
            IndexHeader::parse(bytes.as_ref())?.unwrap_or(default_header);

51233:ca81cd96000a

/// Abstracts the access to the index bytes since they can be spread between
/// the immutable (bytes) part and the mutable (added) part if any appends
/// happened. This makes it transparent for the callers.
struct IndexData {
    /// Immutable bytes, most likely taken from disk
    bytes: Box<dyn Deref<Target = [u8]> + Send + Sync>,
    /// Used when stripping index contents, keeps track of the start of the
    /// first stripped revision, which is used to give a slice of the
    /// `bytes` field.
    truncation: Option<usize>,
    /// Bytes that were added after reading the index
    added: Vec<u8>,
}

impl IndexData {
    pub fn new(bytes: Box<dyn Deref<Target = [u8]> + Send + Sync>) -> Self {
        Self {
            bytes,
            truncation: None,
            added: vec![],
        }

impl Index {
    /// Create an index from bytes.
    /// Calculate the start of each entry when is_inline is true.
    pub fn new(
        bytes: Box<dyn Deref<Target = [u8]> + Send + Sync>,
        default_header: IndexHeader,
    ) -> Result<Self, HgError> {
        let header =
            IndexHeader::parse(bytes.as_ref())?.unwrap_or(default_header);