gix_object/traits/mod.rs
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use std::io;
use crate::Kind;
/// Describe the capability to write git objects into an object store.
pub trait Write {
/// Write objects using the intrinsic kind of [`hash`](gix_hash::Kind) into the database,
/// returning id to reference it in subsequent reads.
fn write(&self, object: &dyn WriteTo) -> Result<gix_hash::ObjectId, crate::write::Error> {
let mut buf = Vec::with_capacity(2048);
object.write_to(&mut buf)?;
self.write_stream(object.kind(), buf.len() as u64, &mut buf.as_slice())
}
/// As [`write`](Write::write), but takes an [`object` kind](Kind) along with its encoded bytes.
fn write_buf(&self, object: crate::Kind, mut from: &[u8]) -> Result<gix_hash::ObjectId, crate::write::Error> {
self.write_stream(object, from.len() as u64, &mut from)
}
/// As [`write`](Write::write), but takes an input stream.
/// This is commonly used for writing blobs directly without reading them to memory first.
fn write_stream(
&self,
kind: crate::Kind,
size: u64,
from: &mut dyn io::Read,
) -> Result<gix_hash::ObjectId, crate::write::Error>;
}
/// Writing of objects to a `Write` implementation
pub trait WriteTo {
/// Write a representation of this instance to `out`.
fn write_to(&self, out: &mut dyn std::io::Write) -> std::io::Result<()>;
/// Returns the type of this object.
fn kind(&self) -> Kind;
/// Returns the size of this object's representation (the amount
/// of data which would be written by [`write_to`](Self::write_to)).
///
/// [`size`](Self::size)'s value has no bearing on the validity of
/// the object, as such it's possible for [`size`](Self::size) to
/// return a sensible value but [`write_to`](Self::write_to) to
/// fail because the object was not actually valid in some way.
fn size(&self) -> u64;
/// Returns a loose object header based on the object's data
fn loose_header(&self) -> smallvec::SmallVec<[u8; 28]> {
crate::encode::loose_header(self.kind(), self.size())
}
}
mod _impls;
mod find;
pub use find::*;