From d4f4d60f6da8b93f768b2b4958c04cc1b3cea443 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Tue, 18 Jun 2019 11:14:24 -0700 Subject: commit-graph: prepare for commit-graph chains To prepare for a chain of commit-graph files, augment the commit_graph struct to point to a base commit_graph. As we load commits from the graph, we may actually want to read from a base file according to the graph position. The "graph position" of a commit is given by concatenating the lexicographic commit orders from each of the commit-graph files in the chain. This means that we must distinguish two values: * lexicographic index : the position within the lexicographic order in a single commit-graph file. * graph position: the position within the concatenated order of multiple commit-graph files Given the lexicographic index of a commit in a graph, we can compute the graph position by adding the number of commits in the lower-level graphs. To find the lexicographic index of a commit, we subtract the number of commits in lower-level graphs. While here, change insert_parent_or_die() to take a uint32_t position, as that is the type used by its only caller and that makes more sense with the limits in the commit-graph format. Signed-off-by: Derrick Stolee Signed-off-by: Junio C Hamano --- commit-graph.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'commit-graph.h') diff --git a/commit-graph.h b/commit-graph.h index 390c7f6961..5819910a5b 100644 --- a/commit-graph.h +++ b/commit-graph.h @@ -48,6 +48,9 @@ struct commit_graph { uint32_t num_commits; struct object_id oid; + uint32_t num_commits_in_base; + struct commit_graph *base_graph; + const uint32_t *chunk_oid_fanout; const unsigned char *chunk_oid_lookup; const unsigned char *chunk_commit_data; -- cgit v1.2.1