1 files changed, 29 insertions, 0 deletions
diff --git a/vendor/gix-index/src/extension/end_of_index_entry/write.rs b/vendor/gix-index/src/extension/end_of_index_entry/write.rs
new file mode 100644
index 000000000..6752bd238
--- /dev/null
+++ b/vendor/gix-index/src/extension/end_of_index_entry/write.rs
@@ -0,0 +1,29 @@
+use crate::extension::{end_of_index_entry::SIGNATURE, Signature};
+
+/// Write this extension to out and generate a hash of `hash_kind` over all `prior_extensions` which are specified as `(signature, size)`
+/// pair. `one_past_entries` is the offset to the first byte past the entries, which is also the first byte of the signature of the
+/// first extension in `prior_extensions`. Note that `prior_extensions` must have been written prior to this one, as the name suggests,
+/// allowing this extension to be the last one in the index file.
+///
+/// Even if there are no `prior_extensions`, this extension will be written unconditionally.
+pub fn write_to(
+    mut out: impl std::io::Write,
+    hash_kind: gix_hash::Kind,
+    offset_to_extensions: u32,
+    prior_extensions: impl IntoIterator<Item = (Signature, u32)>,
+) -> Result<(), std::io::Error> {
+    out.write_all(&SIGNATURE)?;
+    let extension_size: u32 = 4 + hash_kind.len_in_bytes() as u32;
+    out.write_all(&extension_size.to_be_bytes())?;
+
+    out.write_all(&offset_to_extensions.to_be_bytes())?;
+
+    let mut hasher = gix_features::hash::hasher(hash_kind);
+    for (signature, size) in prior_extensions {
+        hasher.update(&signature);
+        hasher.update(&size.to_be_bytes());
+    }
+    out.write_all(&hasher.digest())?;
+
+    Ok(())
+}