1 files changed, 46 insertions, 0 deletions
diff --git a/vendor/gix-commitgraph/src/file/mod.rs b/vendor/gix-commitgraph/src/file/mod.rs
new file mode 100644
index 000000000..528cd69fb
--- /dev/null
+++ b/vendor/gix-commitgraph/src/file/mod.rs
@@ -0,0 +1,46 @@
+//! Operations on a single commit-graph file.
+
+use std::fmt::{Display, Formatter};
+
+pub use self::{commit::Commit, init::Error};
+
+mod access;
+pub mod commit;
+mod init;
+pub mod verify;
+
+const COMMIT_DATA_ENTRY_SIZE_SANS_HASH: usize = 16;
+pub(crate) const FAN_LEN: usize = 256;
+const HEADER_LEN: usize = 8;
+
+const SIGNATURE: &[u8] = b"CGPH";
+
+type ChunkId = gix_chunk::Id;
+const BASE_GRAPHS_LIST_CHUNK_ID: ChunkId = *b"BASE";
+const COMMIT_DATA_CHUNK_ID: ChunkId = *b"CDAT";
+const EXTENDED_EDGES_LIST_CHUNK_ID: ChunkId = *b"EDGE";
+const OID_FAN_CHUNK_ID: ChunkId = *b"OIDF";
+const OID_LOOKUP_CHUNK_ID: ChunkId = *b"OIDL";
+
+// Note that git's commit-graph-format.txt as of v2.28.0 gives an incorrect value 0x0700_0000 for
+// NO_PARENT. Fixed in https://github.com/git/git/commit/4d515253afcef985e94400adbfed7044959f9121 .
+const NO_PARENT: u32 = 0x7000_0000;
+const EXTENDED_EDGES_MASK: u32 = 0x8000_0000;
+const LAST_EXTENDED_EDGE_MASK: u32 = 0x8000_0000;
+
+/// The position of a given commit within a graph file, starting at 0.
+///
+/// Commits within a graph file are sorted in lexicographical order by OID; a commit's lexicographical position
+/// is its position in this ordering. If a commit graph spans multiple files, each file's commits
+/// start at lexicographical position 0, so it is unique across a single file but is not unique across
+/// the whole commit graph. Each commit also has a graph position ([`Position`][crate::Position]),
+/// which is unique across the whole commit graph.
+/// In order to avoid accidentally mixing lexicographical positions with graph positions, distinct types are used for each.
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub struct Position(pub u32);
+
+impl Display for Position {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        self.0.fmt(f)
+    }
+}