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, 72 insertions, 22 deletions

diff --git a/third_party/git/commit-graph.h b/third_party/git/commit-graph.h
index df9a3b20e4ab..f8e92500c6e4 100644
--- a/third_party/git/commit-graph.h
+++ b/third_party/git/commit-graph.h
@@ -2,16 +2,30 @@
 #define COMMIT_GRAPH_H
 
 #include "git-compat-util.h"
-#include "repository.h"
-#include "string-list.h"
-#include "cache.h"
+#include "object-store.h"
+#include "oidset.h"
 
 #define GIT_TEST_COMMIT_GRAPH "GIT_TEST_COMMIT_GRAPH"
-#define GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD "GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD"
+#define GIT_TEST_COMMIT_GRAPH_DIE_ON_PARSE "GIT_TEST_COMMIT_GRAPH_DIE_ON_PARSE"
+#define GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS "GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS"
+
+/*
+ * This method is only used to enhance coverage of the commit-graph
+ * feature in the test suite with the GIT_TEST_COMMIT_GRAPH and
+ * GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS environment variables. Do not
+ * call this method oustide of a builtin, and only if you know what
+ * you are doing!
+ */
+void git_test_write_commit_graph_or_die(void);
 
 struct commit;
+struct bloom_filter_settings;
+struct repository;
+struct raw_object_store;
+struct string_list;
 
-char *get_commit_graph_filename(const char *obj_dir);
+char *get_commit_graph_filename(struct object_directory *odb);
+char *get_commit_graph_chain_filename(struct object_directory *odb);
 int open_commit_graph(const char *graph_file, int *fd, struct stat *st);
 
 /*
@@ -38,8 +52,6 @@ struct tree *get_commit_tree_in_graph(struct repository *r,
 				      const struct commit *c);
 
 struct commit_graph {
-	int graph_fd;
-
 	const unsigned char *data;
 	size_t data_len;
 
@@ -48,7 +60,7 @@ struct commit_graph {
 	uint32_t num_commits;
 	struct object_id oid;
 	char *filename;
-	const char *obj_dir;
+	struct object_directory *odb;
 
 	uint32_t num_commits_in_base;
 	struct commit_graph *base_graph;
@@ -58,12 +70,19 @@ struct commit_graph {
 	const unsigned char *chunk_commit_data;
 	const unsigned char *chunk_extra_edges;
 	const unsigned char *chunk_base_graphs;
+	const unsigned char *chunk_bloom_indexes;
+	const unsigned char *chunk_bloom_data;
+
+	struct bloom_filter_settings *bloom_filter_settings;
 };
 
-struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st);
-struct commit_graph *read_commit_graph_one(struct repository *r, const char *obj_dir);
-struct commit_graph *parse_commit_graph(void *graph_map, int fd,
-					size_t graph_size);
+struct commit_graph *load_commit_graph_one_fd_st(struct repository *r,
+						 int fd, struct stat *st,
+						 struct object_directory *odb);
+struct commit_graph *read_commit_graph_one(struct repository *r,
+					   struct object_directory *odb);
+struct commit_graph *parse_commit_graph(struct repository *r,
+					void *graph_map, size_t graph_size);
 
 /*
  * Return 1 if and only if the repository has a commit-graph
@@ -71,14 +90,28 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
  */
 int generation_numbers_enabled(struct repository *r);
 
-#define COMMIT_GRAPH_APPEND     (1 << 0)
-#define COMMIT_GRAPH_PROGRESS   (1 << 1)
-#define COMMIT_GRAPH_SPLIT      (1 << 2)
+struct bloom_filter_settings *get_bloom_filter_settings(struct repository *r);
+
+enum commit_graph_write_flags {
+	COMMIT_GRAPH_WRITE_APPEND     = (1 << 0),
+	COMMIT_GRAPH_WRITE_PROGRESS   = (1 << 1),
+	COMMIT_GRAPH_WRITE_SPLIT      = (1 << 2),
+	COMMIT_GRAPH_WRITE_BLOOM_FILTERS = (1 << 3),
+	COMMIT_GRAPH_NO_WRITE_BLOOM_FILTERS = (1 << 4),
+};
+
+enum commit_graph_split_flags {
+	COMMIT_GRAPH_SPLIT_UNSPECIFIED      = 0,
+	COMMIT_GRAPH_SPLIT_MERGE_PROHIBITED = 1,
+	COMMIT_GRAPH_SPLIT_REPLACE          = 2
+};
 
-struct split_commit_graph_opts {
+struct commit_graph_opts {
 	int size_multiple;
 	int max_commits;
 	timestamp_t expire_time;
+	enum commit_graph_split_flags split_flags;
+	int max_new_filters;
 };
 
 /*
@@ -87,13 +120,14 @@ struct split_commit_graph_opts {
  * is not compatible with the commit-graph feature, then the
  * methods will return 0 without writing a commit-graph.
  */
-int write_commit_graph_reachable(const char *obj_dir, unsigned int flags,
-				 const struct split_commit_graph_opts *split_opts);
-int write_commit_graph(const char *obj_dir,
+int write_commit_graph_reachable(struct object_directory *odb,
+				 enum commit_graph_write_flags flags,
+				 const struct commit_graph_opts *opts);
+int write_commit_graph(struct object_directory *odb,
 		       struct string_list *pack_indexes,
-		       struct string_list *commit_hex,
-		       unsigned int flags,
-		       const struct split_commit_graph_opts *split_opts);
+		       struct oidset *commits,
+		       enum commit_graph_write_flags flags,
+		       const struct commit_graph_opts *opts);
 
 #define COMMIT_GRAPH_VERIFY_SHALLOW	(1 << 0)
 
@@ -102,4 +136,20 @@ int verify_commit_graph(struct repository *r, struct commit_graph *g, int flags)
 void close_commit_graph(struct raw_object_store *);
 void free_commit_graph(struct commit_graph *);
 
+/*
+ * Disable further use of the commit graph in this process when parsing a
+ * "struct commit".
+ */
+void disable_commit_graph(struct repository *r);
+
+struct commit_graph_data {
+	uint32_t graph_pos;
+	uint32_t generation;
+};
+
+/*
+ * Commits should be parsed before accessing generation, graph positions.
+ */
+uint32_t commit_graph_generation(const struct commit *);
+uint32_t commit_graph_position(const struct commit *);
 #endif