merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 49 insertions, 3 deletions

diff --git a/third_party/git/repository.h b/third_party/git/repository.h
index 4fb6a5885f..bacf843d46 100644
--- a/third_party/git/repository.h
+++ b/third_party/git/repository.h
@@ -11,6 +11,36 @@ struct pathspec;
 struct raw_object_store;
 struct submodule_cache;
 
+enum untracked_cache_setting {
+	UNTRACKED_CACHE_UNSET = -1,
+	UNTRACKED_CACHE_REMOVE = 0,
+	UNTRACKED_CACHE_KEEP = 1,
+	UNTRACKED_CACHE_WRITE = 2
+};
+
+enum fetch_negotiation_setting {
+	FETCH_NEGOTIATION_UNSET = -1,
+	FETCH_NEGOTIATION_NONE = 0,
+	FETCH_NEGOTIATION_DEFAULT = 1,
+	FETCH_NEGOTIATION_SKIPPING = 2,
+	FETCH_NEGOTIATION_NOOP = 3,
+};
+
+struct repo_settings {
+	int initialized;
+
+	int core_commit_graph;
+	int commit_graph_read_changed_paths;
+	int gc_write_commit_graph;
+	int fetch_write_commit_graph;
+
+	int index_version;
+	enum untracked_cache_setting core_untracked_cache;
+
+	int pack_use_sparse;
+	enum fetch_negotiation_setting fetch_negotiation_algorithm;
+};
+
 struct repository {
 	/* Environment */
 	/*
@@ -39,8 +69,12 @@ struct repository {
 	 */
 	struct parsed_object_pool *parsed_objects;
 
-	/* The store in which the refs are held. */
-	struct ref_store *refs;
+	/*
+	 * The store in which the refs are held. This should generally only be
+	 * accessed via get_main_ref_store(), as that will lazily initialize
+	 * the ref object.
+	 */
+	struct ref_store *refs_private;
 
 	/*
 	 * Contains path to often used file names.
@@ -72,6 +106,8 @@ struct repository {
 	 */
 	char *submodule_prefix;
 
+	struct repo_settings settings;
+
 	/* Subsystems */
 	/*
 	 * Repository's config which contains key-value pairs from the usual
@@ -95,6 +131,9 @@ struct repository {
 	/* A unique-id for tracing purposes. */
 	int trace2_repo_id;
 
+	/* True if commit-graph has been disabled within this process. */
+	int commit_graph_disabled;
+
 	/* Configurations */
 
 	/* Indicate if a repository has a different 'commondir' from 'gitdir' */
@@ -139,7 +178,7 @@ void repo_clear(struct repository *repo);
  * be allocated if needed.
  *
  * Return the number of index entries in the populated index or a value less
- * than zero if an error occured.  If the repository's index has already been
+ * than zero if an error occurred.  If the repository's index has already been
  * populated then the number of entries will simply be returned.
  */
 int repo_read_index(struct repository *repo);
@@ -157,5 +196,12 @@ int repo_read_index_unmerged(struct repository *);
  */
 void repo_update_index_if_able(struct repository *, struct lock_file *);
 
+void prepare_repo_settings(struct repository *r);
+
+/*
+ * Return 1 if upgrade repository format to target_version succeeded,
+ * 0 if no upgrade is necessary, and -1 when upgrade is not possible.
+ */
+int upgrade_repository_format(int target_version);
 
 #endif /* REPOSITORY_H */