path: root/commit-graph.h
diff options
authorDerrick Stolee <>2019-06-18 18:14:24 (GMT)
committerJunio C Hamano <>2019-06-20 03:46:25 (GMT)
commitd4f4d60f6da8b93f768b2b4958c04cc1b3cea443 (patch)
tree1f88453dc1b3ff7d3e126b2288c9ae7076b360e3 /commit-graph.h
parent890345ac106f78dfcfcde002de39ebbb410e0b39 (diff)
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 <>
Diffstat (limited to 'commit-graph.h')
1 files changed, 3 insertions, 0 deletions
diff --git a/commit-graph.h b/commit-graph.h
index 390c7f6..5819910 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;