generalize extension writing so that writing more will be easier

Sebastian Thiel committed 4 years ago

Commit 8ef53781 parent 18b722e2 files · +29 −15Browse files

Unified · Split

2 files

git-index/src/extension/end_of_index_entry/write.rs +2 −2
git-index/src/write.rs +27 −13

git-index/src/extension/end_of_index_entry/write.rs+2−2

@@ -11,7 +11,7 @@ pub fn write_to( · 10 unmodified lines
11	11	out: &mut impl std::io::Write,
12	12	hash_kind: git_hash::Kind,
13	13	offset_to_extensions: u32,
14		− prior_extensions: &[(Signature, u32)],
	14	+ prior_extensions: impl Iterator<Item = (Signature, u32)>,
15	15	) -> Result<(), std::io::Error> {
16	16	out.write_all(&SIGNATURE)?;
17	17	let extension_size: u32 = 4 + hash_kind.len_in_bytes() as u32;
@@ -21,7 +21,7 @@ pub fn write_to( · 3 unmodified lines
21	21
22	22	let mut hasher = git_features::hash::hasher(hash_kind);
23	23	for (signature, size) in prior_extensions {
24		− hasher.update(signature);
	24	+ hasher.update(&signature);
25	25	hasher.update(&size.to_be_bytes());
26	26	}
27	27	out.write_all(&hasher.digest())?;

git-index/src/write.rs+27−13

@@ -63,21 +63,35 @@ impl State { · 62 unmodified lines
63	63	let offset_to_entries = header(&mut write, version, num_entries)?;
64	64	let offset_to_extensions = entries(&mut write, self, offset_to_entries)?;
65	65
66		− let mut extensions = Vec::with_capacity(5);
67		− if let Some(offset_past_tree_ext) = tree_cache_extension
68		− .then(\|\| self.tree())
69		− .flatten()
70		− .map(\|tree\| tree.write_to(&mut write).map(\|_\| write.count))
71		− .transpose()?
72		− {
73		− extensions.push((
74		− extension::tree::SIGNATURE,
75		− offset_past_tree_ext - offset_to_extensions - (extension::MIN_SIZE as u32),
76		− ));
77		− }
	66	+ let extensions = {
	67	+ let extensions: &[&dyn Fn(&mut dyn std::io::Write) -> Option<std::io::Result<extension::Signature>>] =
	68	+ &[&\|write\| {
	69	+ tree_cache_extension
	70	+ .then(\|\| self.tree())
	71	+ .flatten()
	72	+ .map(\|tree\| tree.write_to(write).map(\|_\| extension::tree::SIGNATURE))
	73	+ }];
	74	+
	75	+ let mut offset_to_previous_ext = offset_to_extensions;
	76	+ let mut out = Vec::with_capacity(5);
	77	+ for write_ext in extensions {
	78	+ if let Some(signature) = write_ext(&mut write).transpose()? {
	79	+ let offset_past_ext = write.count;
	80	+ let ext_size = offset_past_ext - offset_to_previous_ext - (extension::MIN_SIZE as u32);
	81	+ offset_to_previous_ext = offset_past_ext;
	82	+ out.push((signature, ext_size));
	83	+ }
	84	+ }
	85	+ out
	86	+ };
78	87
79	88	if num_entries > 0 && end_of_index_entry_extension && !extensions.is_empty() {
80		− extension::end_of_index_entry::write_to(write.inner, hash_kind, offset_to_extensions, &extensions)?
	89	+ extension::end_of_index_entry::write_to(
	90	+ write.inner,
	91	+ hash_kind,
	92	+ offset_to_extensions,
	93	+ extensions.into_iter(),
	94	+ )?
81	95	}
82	96
83	97	Ok(())