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-rw-r--r--third_party/git/commit-graph.c2097
1 files changed, 0 insertions, 2097 deletions
diff --git a/third_party/git/commit-graph.c b/third_party/git/commit-graph.c
deleted file mode 100644
index fe954ab5f8..0000000000
--- a/third_party/git/commit-graph.c
+++ /dev/null
@@ -1,2097 +0,0 @@
-#include "cache.h"
-#include "config.h"
-#include "dir.h"
-#include "git-compat-util.h"
-#include "lockfile.h"
-#include "pack.h"
-#include "packfile.h"
-#include "commit.h"
-#include "object.h"
-#include "refs.h"
-#include "revision.h"
-#include "sha1-lookup.h"
-#include "commit-graph.h"
-#include "object-store.h"
-#include "alloc.h"
-#include "hashmap.h"
-#include "replace-object.h"
-#include "progress.h"
-
-#define GRAPH_SIGNATURE 0x43475048 /* "CGPH" */
-#define GRAPH_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
-#define GRAPH_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
-#define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */
-#define GRAPH_CHUNKID_EXTRAEDGES 0x45444745 /* "EDGE" */
-#define GRAPH_CHUNKID_BASE 0x42415345 /* "BASE" */
-
-#define GRAPH_DATA_WIDTH (the_hash_algo->rawsz + 16)
-
-#define GRAPH_VERSION_1 0x1
-#define GRAPH_VERSION GRAPH_VERSION_1
-
-#define GRAPH_EXTRA_EDGES_NEEDED 0x80000000
-#define GRAPH_EDGE_LAST_MASK 0x7fffffff
-#define GRAPH_PARENT_NONE 0x70000000
-
-#define GRAPH_LAST_EDGE 0x80000000
-
-#define GRAPH_HEADER_SIZE 8
-#define GRAPH_FANOUT_SIZE (4 * 256)
-#define GRAPH_CHUNKLOOKUP_WIDTH 12
-#define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
-			+ GRAPH_FANOUT_SIZE + the_hash_algo->rawsz)
-
-char *get_commit_graph_filename(const char *obj_dir)
-{
-	char *filename = xstrfmt("%s/info/commit-graph", obj_dir);
-	char *normalized = xmalloc(strlen(filename) + 1);
-	normalize_path_copy(normalized, filename);
-	free(filename);
-	return normalized;
-}
-
-static char *get_split_graph_filename(const char *obj_dir,
-				      const char *oid_hex)
-{
-	char *filename = xstrfmt("%s/info/commit-graphs/graph-%s.graph",
-				 obj_dir,
-				 oid_hex);
-	char *normalized = xmalloc(strlen(filename) + 1);
-	normalize_path_copy(normalized, filename);
-	free(filename);
-	return normalized;
-}
-
-static char *get_chain_filename(const char *obj_dir)
-{
-	return xstrfmt("%s/info/commit-graphs/commit-graph-chain", obj_dir);
-}
-
-static uint8_t oid_version(void)
-{
-	return 1;
-}
-
-static struct commit_graph *alloc_commit_graph(void)
-{
-	struct commit_graph *g = xcalloc(1, sizeof(*g));
-	g->graph_fd = -1;
-
-	return g;
-}
-
-extern int read_replace_refs;
-
-static int commit_graph_compatible(struct repository *r)
-{
-	if (!r->gitdir)
-		return 0;
-
-	if (read_replace_refs) {
-		prepare_replace_object(r);
-		if (hashmap_get_size(&r->objects->replace_map->map))
-			return 0;
-	}
-
-	prepare_commit_graft(r);
-	if (r->parsed_objects && r->parsed_objects->grafts_nr)
-		return 0;
-	if (is_repository_shallow(r))
-		return 0;
-
-	return 1;
-}
-
-int open_commit_graph(const char *graph_file, int *fd, struct stat *st)
-{
-	*fd = git_open(graph_file);
-	if (*fd < 0)
-		return 0;
-	if (fstat(*fd, st)) {
-		close(*fd);
-		return 0;
-	}
-	return 1;
-}
-
-struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st)
-{
-	void *graph_map;
-	size_t graph_size;
-	struct commit_graph *ret;
-
-	graph_size = xsize_t(st->st_size);
-
-	if (graph_size < GRAPH_MIN_SIZE) {
-		close(fd);
-		error(_("commit-graph file is too small"));
-		return NULL;
-	}
-	graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
-	ret = parse_commit_graph(graph_map, fd, graph_size);
-
-	if (!ret) {
-		munmap(graph_map, graph_size);
-		close(fd);
-	}
-
-	return ret;
-}
-
-static int verify_commit_graph_lite(struct commit_graph *g)
-{
-	/*
-	 * Basic validation shared between parse_commit_graph()
-	 * which'll be called every time the graph is used, and the
-	 * much more expensive verify_commit_graph() used by
-	 * "commit-graph verify".
-	 *
-	 * There should only be very basic checks here to ensure that
-	 * we don't e.g. segfault in fill_commit_in_graph(), but
-	 * because this is a very hot codepath nothing that e.g. loops
-	 * over g->num_commits, or runs a checksum on the commit-graph
-	 * itself.
-	 */
-	if (!g->chunk_oid_fanout) {
-		error("commit-graph is missing the OID Fanout chunk");
-		return 1;
-	}
-	if (!g->chunk_oid_lookup) {
-		error("commit-graph is missing the OID Lookup chunk");
-		return 1;
-	}
-	if (!g->chunk_commit_data) {
-		error("commit-graph is missing the Commit Data chunk");
-		return 1;
-	}
-
-	return 0;
-}
-
-struct commit_graph *parse_commit_graph(void *graph_map, int fd,
-					size_t graph_size)
-{
-	const unsigned char *data, *chunk_lookup;
-	uint32_t i;
-	struct commit_graph *graph;
-	uint64_t last_chunk_offset;
-	uint32_t last_chunk_id;
-	uint32_t graph_signature;
-	unsigned char graph_version, hash_version;
-
-	if (!graph_map)
-		return NULL;
-
-	if (graph_size < GRAPH_MIN_SIZE)
-		return NULL;
-
-	data = (const unsigned char *)graph_map;
-
-	graph_signature = get_be32(data);
-	if (graph_signature != GRAPH_SIGNATURE) {
-		error(_("commit-graph signature %X does not match signature %X"),
-		      graph_signature, GRAPH_SIGNATURE);
-		return NULL;
-	}
-
-	graph_version = *(unsigned char*)(data + 4);
-	if (graph_version != GRAPH_VERSION) {
-		error(_("commit-graph version %X does not match version %X"),
-		      graph_version, GRAPH_VERSION);
-		return NULL;
-	}
-
-	hash_version = *(unsigned char*)(data + 5);
-	if (hash_version != oid_version()) {
-		error(_("commit-graph hash version %X does not match version %X"),
-		      hash_version, oid_version());
-		return NULL;
-	}
-
-	graph = alloc_commit_graph();
-
-	graph->hash_len = the_hash_algo->rawsz;
-	graph->num_chunks = *(unsigned char*)(data + 6);
-	graph->graph_fd = fd;
-	graph->data = graph_map;
-	graph->data_len = graph_size;
-
-	last_chunk_id = 0;
-	last_chunk_offset = 8;
-	chunk_lookup = data + 8;
-	for (i = 0; i < graph->num_chunks; i++) {
-		uint32_t chunk_id;
-		uint64_t chunk_offset;
-		int chunk_repeated = 0;
-
-		if (data + graph_size - chunk_lookup <
-		    GRAPH_CHUNKLOOKUP_WIDTH) {
-			error(_("commit-graph chunk lookup table entry missing; file may be incomplete"));
-			free(graph);
-			return NULL;
-		}
-
-		chunk_id = get_be32(chunk_lookup + 0);
-		chunk_offset = get_be64(chunk_lookup + 4);
-
-		chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
-
-		if (chunk_offset > graph_size - the_hash_algo->rawsz) {
-			error(_("commit-graph improper chunk offset %08x%08x"), (uint32_t)(chunk_offset >> 32),
-			      (uint32_t)chunk_offset);
-			free(graph);
-			return NULL;
-		}
-
-		switch (chunk_id) {
-		case GRAPH_CHUNKID_OIDFANOUT:
-			if (graph->chunk_oid_fanout)
-				chunk_repeated = 1;
-			else
-				graph->chunk_oid_fanout = (uint32_t*)(data + chunk_offset);
-			break;
-
-		case GRAPH_CHUNKID_OIDLOOKUP:
-			if (graph->chunk_oid_lookup)
-				chunk_repeated = 1;
-			else
-				graph->chunk_oid_lookup = data + chunk_offset;
-			break;
-
-		case GRAPH_CHUNKID_DATA:
-			if (graph->chunk_commit_data)
-				chunk_repeated = 1;
-			else
-				graph->chunk_commit_data = data + chunk_offset;
-			break;
-
-		case GRAPH_CHUNKID_EXTRAEDGES:
-			if (graph->chunk_extra_edges)
-				chunk_repeated = 1;
-			else
-				graph->chunk_extra_edges = data + chunk_offset;
-			break;
-
-		case GRAPH_CHUNKID_BASE:
-			if (graph->chunk_base_graphs)
-				chunk_repeated = 1;
-			else
-				graph->chunk_base_graphs = data + chunk_offset;
-		}
-
-		if (chunk_repeated) {
-			error(_("commit-graph chunk id %08x appears multiple times"), chunk_id);
-			free(graph);
-			return NULL;
-		}
-
-		if (last_chunk_id == GRAPH_CHUNKID_OIDLOOKUP)
-		{
-			graph->num_commits = (chunk_offset - last_chunk_offset)
-					     / graph->hash_len;
-		}
-
-		last_chunk_id = chunk_id;
-		last_chunk_offset = chunk_offset;
-	}
-
-	hashcpy(graph->oid.hash, graph->data + graph->data_len - graph->hash_len);
-
-	if (verify_commit_graph_lite(graph)) {
-		free(graph);
-		return NULL;
-	}
-
-	return graph;
-}
-
-static struct commit_graph *load_commit_graph_one(const char *graph_file)
-{
-
-	struct stat st;
-	int fd;
-	struct commit_graph *g;
-	int open_ok = open_commit_graph(graph_file, &fd, &st);
-
-	if (!open_ok)
-		return NULL;
-
-	g = load_commit_graph_one_fd_st(fd, &st);
-
-	if (g)
-		g->filename = xstrdup(graph_file);
-
-	return g;
-}
-
-static struct commit_graph *load_commit_graph_v1(struct repository *r, const char *obj_dir)
-{
-	char *graph_name = get_commit_graph_filename(obj_dir);
-	struct commit_graph *g = load_commit_graph_one(graph_name);
-	free(graph_name);
-
-	if (g)
-		g->obj_dir = obj_dir;
-
-	return g;
-}
-
-static int add_graph_to_chain(struct commit_graph *g,
-			      struct commit_graph *chain,
-			      struct object_id *oids,
-			      int n)
-{
-	struct commit_graph *cur_g = chain;
-
-	if (n && !g->chunk_base_graphs) {
-		warning(_("commit-graph has no base graphs chunk"));
-		return 0;
-	}
-
-	while (n) {
-		n--;
-
-		if (!cur_g ||
-		    !oideq(&oids[n], &cur_g->oid) ||
-		    !hasheq(oids[n].hash, g->chunk_base_graphs + g->hash_len * n)) {
-			warning(_("commit-graph chain does not match"));
-			return 0;
-		}
-
-		cur_g = cur_g->base_graph;
-	}
-
-	g->base_graph = chain;
-
-	if (chain)
-		g->num_commits_in_base = chain->num_commits + chain->num_commits_in_base;
-
-	return 1;
-}
-
-static struct commit_graph *load_commit_graph_chain(struct repository *r, const char *obj_dir)
-{
-	struct commit_graph *graph_chain = NULL;
-	struct strbuf line = STRBUF_INIT;
-	struct stat st;
-	struct object_id *oids;
-	int i = 0, valid = 1, count;
-	char *chain_name = get_chain_filename(obj_dir);
-	FILE *fp;
-	int stat_res;
-
-	fp = fopen(chain_name, "r");
-	stat_res = stat(chain_name, &st);
-	free(chain_name);
-
-	if (!fp ||
-	    stat_res ||
-	    st.st_size <= the_hash_algo->hexsz)
-		return NULL;
-
-	count = st.st_size / (the_hash_algo->hexsz + 1);
-	oids = xcalloc(count, sizeof(struct object_id));
-
-	prepare_alt_odb(r);
-
-	for (i = 0; i < count; i++) {
-		struct object_directory *odb;
-
-		if (strbuf_getline_lf(&line, fp) == EOF)
-			break;
-
-		if (get_oid_hex(line.buf, &oids[i])) {
-			warning(_("invalid commit-graph chain: line '%s' not a hash"),
-				line.buf);
-			valid = 0;
-			break;
-		}
-
-		valid = 0;
-		for (odb = r->objects->odb; odb; odb = odb->next) {
-			char *graph_name = get_split_graph_filename(odb->path, line.buf);
-			struct commit_graph *g = load_commit_graph_one(graph_name);
-
-			free(graph_name);
-
-			if (g) {
-				g->obj_dir = odb->path;
-
-				if (add_graph_to_chain(g, graph_chain, oids, i)) {
-					graph_chain = g;
-					valid = 1;
-				}
-
-				break;
-			}
-		}
-
-		if (!valid) {
-			warning(_("unable to find all commit-graph files"));
-			break;
-		}
-	}
-
-	free(oids);
-	fclose(fp);
-	strbuf_release(&line);
-
-	return graph_chain;
-}
-
-struct commit_graph *read_commit_graph_one(struct repository *r, const char *obj_dir)
-{
-	struct commit_graph *g = load_commit_graph_v1(r, obj_dir);
-
-	if (!g)
-		g = load_commit_graph_chain(r, obj_dir);
-
-	return g;
-}
-
-static void prepare_commit_graph_one(struct repository *r, const char *obj_dir)
-{
-
-	if (r->objects->commit_graph)
-		return;
-
-	r->objects->commit_graph = read_commit_graph_one(r, obj_dir);
-}
-
-/*
- * Return 1 if commit_graph is non-NULL, and 0 otherwise.
- *
- * On the first invocation, this function attemps to load the commit
- * graph if the_repository is configured to have one.
- */
-static int prepare_commit_graph(struct repository *r)
-{
-	struct object_directory *odb;
-	int config_value;
-
-	if (git_env_bool(GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD, 0))
-		die("dying as requested by the '%s' variable on commit-graph load!",
-		    GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD);
-
-	if (r->objects->commit_graph_attempted)
-		return !!r->objects->commit_graph;
-	r->objects->commit_graph_attempted = 1;
-
-	if (!git_env_bool(GIT_TEST_COMMIT_GRAPH, 0) &&
-	    (repo_config_get_bool(r, "core.commitgraph", &config_value) ||
-	    !config_value))
-		/*
-		 * This repository is not configured to use commit graphs, so
-		 * do not load one. (But report commit_graph_attempted anyway
-		 * so that commit graph loading is not attempted again for this
-		 * repository.)
-		 */
-		return 0;
-
-	if (!commit_graph_compatible(r))
-		return 0;
-
-	prepare_alt_odb(r);
-	for (odb = r->objects->odb;
-	     !r->objects->commit_graph && odb;
-	     odb = odb->next)
-		prepare_commit_graph_one(r, odb->path);
-	return !!r->objects->commit_graph;
-}
-
-int generation_numbers_enabled(struct repository *r)
-{
-	uint32_t first_generation;
-	struct commit_graph *g;
-	if (!prepare_commit_graph(r))
-	       return 0;
-
-	g = r->objects->commit_graph;
-
-	if (!g->num_commits)
-		return 0;
-
-	first_generation = get_be32(g->chunk_commit_data +
-				    g->hash_len + 8) >> 2;
-
-	return !!first_generation;
-}
-
-static void close_commit_graph_one(struct commit_graph *g)
-{
-	if (!g)
-		return;
-
-	close_commit_graph_one(g->base_graph);
-	free_commit_graph(g);
-}
-
-void close_commit_graph(struct raw_object_store *o)
-{
-	close_commit_graph_one(o->commit_graph);
-	o->commit_graph = NULL;
-}
-
-static int bsearch_graph(struct commit_graph *g, struct object_id *oid, uint32_t *pos)
-{
-	return bsearch_hash(oid->hash, g->chunk_oid_fanout,
-			    g->chunk_oid_lookup, g->hash_len, pos);
-}
-
-static void load_oid_from_graph(struct commit_graph *g,
-				uint32_t pos,
-				struct object_id *oid)
-{
-	uint32_t lex_index;
-
-	while (g && pos < g->num_commits_in_base)
-		g = g->base_graph;
-
-	if (!g)
-		BUG("NULL commit-graph");
-
-	if (pos >= g->num_commits + g->num_commits_in_base)
-		die(_("invalid commit position. commit-graph is likely corrupt"));
-
-	lex_index = pos - g->num_commits_in_base;
-
-	hashcpy(oid->hash, g->chunk_oid_lookup + g->hash_len * lex_index);
-}
-
-static struct commit_list **insert_parent_or_die(struct repository *r,
-						 struct commit_graph *g,
-						 uint32_t pos,
-						 struct commit_list **pptr)
-{
-	struct commit *c;
-	struct object_id oid;
-
-	if (pos >= g->num_commits + g->num_commits_in_base)
-		die("invalid parent position %"PRIu32, pos);
-
-	load_oid_from_graph(g, pos, &oid);
-	c = lookup_commit(r, &oid);
-	if (!c)
-		die(_("could not find commit %s"), oid_to_hex(&oid));
-	c->graph_pos = pos;
-	return &commit_list_insert(c, pptr)->next;
-}
-
-static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, uint32_t pos)
-{
-	const unsigned char *commit_data;
-	uint32_t lex_index;
-
-	while (pos < g->num_commits_in_base)
-		g = g->base_graph;
-
-	lex_index = pos - g->num_commits_in_base;
-	commit_data = g->chunk_commit_data + GRAPH_DATA_WIDTH * lex_index;
-	item->graph_pos = pos;
-	item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
-}
-
-static inline void set_commit_tree(struct commit *c, struct tree *t)
-{
-	c->maybe_tree = t;
-}
-
-static int fill_commit_in_graph(struct repository *r,
-				struct commit *item,
-				struct commit_graph *g, uint32_t pos)
-{
-	uint32_t edge_value;
-	uint32_t *parent_data_ptr;
-	uint64_t date_low, date_high;
-	struct commit_list **pptr;
-	const unsigned char *commit_data;
-	uint32_t lex_index;
-
-	while (pos < g->num_commits_in_base)
-		g = g->base_graph;
-
-	if (pos >= g->num_commits + g->num_commits_in_base)
-		die(_("invalid commit position. commit-graph is likely corrupt"));
-
-	/*
-	 * Store the "full" position, but then use the
-	 * "local" position for the rest of the calculation.
-	 */
-	item->graph_pos = pos;
-	lex_index = pos - g->num_commits_in_base;
-
-	commit_data = g->chunk_commit_data + (g->hash_len + 16) * lex_index;
-
-	item->object.parsed = 1;
-
-	set_commit_tree(item, NULL);
-
-	date_high = get_be32(commit_data + g->hash_len + 8) & 0x3;
-	date_low = get_be32(commit_data + g->hash_len + 12);
-	item->date = (timestamp_t)((date_high << 32) | date_low);
-
-	item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
-
-	pptr = &item->parents;
-
-	edge_value = get_be32(commit_data + g->hash_len);
-	if (edge_value == GRAPH_PARENT_NONE)
-		return 1;
-	pptr = insert_parent_or_die(r, g, edge_value, pptr);
-
-	edge_value = get_be32(commit_data + g->hash_len + 4);
-	if (edge_value == GRAPH_PARENT_NONE)
-		return 1;
-	if (!(edge_value & GRAPH_EXTRA_EDGES_NEEDED)) {
-		pptr = insert_parent_or_die(r, g, edge_value, pptr);
-		return 1;
-	}
-
-	parent_data_ptr = (uint32_t*)(g->chunk_extra_edges +
-			  4 * (uint64_t)(edge_value & GRAPH_EDGE_LAST_MASK));
-	do {
-		edge_value = get_be32(parent_data_ptr);
-		pptr = insert_parent_or_die(r, g,
-					    edge_value & GRAPH_EDGE_LAST_MASK,
-					    pptr);
-		parent_data_ptr++;
-	} while (!(edge_value & GRAPH_LAST_EDGE));
-
-	return 1;
-}
-
-static int find_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t *pos)
-{
-	if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
-		*pos = item->graph_pos;
-		return 1;
-	} else {
-		struct commit_graph *cur_g = g;
-		uint32_t lex_index;
-
-		while (cur_g && !bsearch_graph(cur_g, &(item->object.oid), &lex_index))
-			cur_g = cur_g->base_graph;
-
-		if (cur_g) {
-			*pos = lex_index + cur_g->num_commits_in_base;
-			return 1;
-		}
-
-		return 0;
-	}
-}
-
-static int parse_commit_in_graph_one(struct repository *r,
-				     struct commit_graph *g,
-				     struct commit *item)
-{
-	uint32_t pos;
-
-	if (item->object.parsed)
-		return 1;
-
-	if (find_commit_in_graph(item, g, &pos))
-		return fill_commit_in_graph(r, item, g, pos);
-
-	return 0;
-}
-
-int parse_commit_in_graph(struct repository *r, struct commit *item)
-{
-	if (!prepare_commit_graph(r))
-		return 0;
-	return parse_commit_in_graph_one(r, r->objects->commit_graph, item);
-}
-
-void load_commit_graph_info(struct repository *r, struct commit *item)
-{
-	uint32_t pos;
-	if (!prepare_commit_graph(r))
-		return;
-	if (find_commit_in_graph(item, r->objects->commit_graph, &pos))
-		fill_commit_graph_info(item, r->objects->commit_graph, pos);
-}
-
-static struct tree *load_tree_for_commit(struct repository *r,
-					 struct commit_graph *g,
-					 struct commit *c)
-{
-	struct object_id oid;
-	const unsigned char *commit_data;
-
-	while (c->graph_pos < g->num_commits_in_base)
-		g = g->base_graph;
-
-	commit_data = g->chunk_commit_data +
-			GRAPH_DATA_WIDTH * (c->graph_pos - g->num_commits_in_base);
-
-	hashcpy(oid.hash, commit_data);
-	set_commit_tree(c, lookup_tree(r, &oid));
-
-	return c->maybe_tree;
-}
-
-static struct tree *get_commit_tree_in_graph_one(struct repository *r,
-						 struct commit_graph *g,
-						 const struct commit *c)
-{
-	if (c->maybe_tree)
-		return c->maybe_tree;
-	if (c->graph_pos == COMMIT_NOT_FROM_GRAPH)
-		BUG("get_commit_tree_in_graph_one called from non-commit-graph commit");
-
-	return load_tree_for_commit(r, g, (struct commit *)c);
-}
-
-struct tree *get_commit_tree_in_graph(struct repository *r, const struct commit *c)
-{
-	return get_commit_tree_in_graph_one(r, r->objects->commit_graph, c);
-}
-
-struct packed_commit_list {
-	struct commit **list;
-	int nr;
-	int alloc;
-};
-
-struct packed_oid_list {
-	struct object_id *list;
-	int nr;
-	int alloc;
-};
-
-struct write_commit_graph_context {
-	struct repository *r;
-	char *obj_dir;
-	char *graph_name;
-	struct packed_oid_list oids;
-	struct packed_commit_list commits;
-	int num_extra_edges;
-	unsigned long approx_nr_objects;
-	struct progress *progress;
-	int progress_done;
-	uint64_t progress_cnt;
-
-	char *base_graph_name;
-	int num_commit_graphs_before;
-	int num_commit_graphs_after;
-	char **commit_graph_filenames_before;
-	char **commit_graph_filenames_after;
-	char **commit_graph_hash_after;
-	uint32_t new_num_commits_in_base;
-	struct commit_graph *new_base_graph;
-
-	unsigned append:1,
-		 report_progress:1,
-		 split:1;
-
-	const struct split_commit_graph_opts *split_opts;
-};
-
-static void write_graph_chunk_fanout(struct hashfile *f,
-				     struct write_commit_graph_context *ctx)
-{
-	int i, count = 0;
-	struct commit **list = ctx->commits.list;
-
-	/*
-	 * Write the first-level table (the list is sorted,
-	 * but we use a 256-entry lookup to be able to avoid
-	 * having to do eight extra binary search iterations).
-	 */
-	for (i = 0; i < 256; i++) {
-		while (count < ctx->commits.nr) {
-			if ((*list)->object.oid.hash[0] != i)
-				break;
-			display_progress(ctx->progress, ++ctx->progress_cnt);
-			count++;
-			list++;
-		}
-
-		hashwrite_be32(f, count);
-	}
-}
-
-static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
-				   struct write_commit_graph_context *ctx)
-{
-	struct commit **list = ctx->commits.list;
-	int count;
-	for (count = 0; count < ctx->commits.nr; count++, list++) {
-		display_progress(ctx->progress, ++ctx->progress_cnt);
-		hashwrite(f, (*list)->object.oid.hash, (int)hash_len);
-	}
-}
-
-static const unsigned char *commit_to_sha1(size_t index, void *table)
-{
-	struct commit **commits = table;
-	return commits[index]->object.oid.hash;
-}
-
-static void write_graph_chunk_data(struct hashfile *f, int hash_len,
-				   struct write_commit_graph_context *ctx)
-{
-	struct commit **list = ctx->commits.list;
-	struct commit **last = ctx->commits.list + ctx->commits.nr;
-	uint32_t num_extra_edges = 0;
-
-	while (list < last) {
-		struct commit_list *parent;
-		int edge_value;
-		uint32_t packedDate[2];
-		display_progress(ctx->progress, ++ctx->progress_cnt);
-
-		parse_commit_no_graph(*list);
-		hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
-
-		parent = (*list)->parents;
-
-		if (!parent)
-			edge_value = GRAPH_PARENT_NONE;
-		else {
-			edge_value = sha1_pos(parent->item->object.oid.hash,
-					      ctx->commits.list,
-					      ctx->commits.nr,
-					      commit_to_sha1);
-
-			if (edge_value >= 0)
-				edge_value += ctx->new_num_commits_in_base;
-			else {
-				uint32_t pos;
-				if (find_commit_in_graph(parent->item,
-							 ctx->new_base_graph,
-							 &pos))
-					edge_value = pos;
-			}
-
-			if (edge_value < 0)
-				BUG("missing parent %s for commit %s",
-				    oid_to_hex(&parent->item->object.oid),
-				    oid_to_hex(&(*list)->object.oid));
-		}
-
-		hashwrite_be32(f, edge_value);
-
-		if (parent)
-			parent = parent->next;
-
-		if (!parent)
-			edge_value = GRAPH_PARENT_NONE;
-		else if (parent->next)
-			edge_value = GRAPH_EXTRA_EDGES_NEEDED | num_extra_edges;
-		else {
-			edge_value = sha1_pos(parent->item->object.oid.hash,
-					      ctx->commits.list,
-					      ctx->commits.nr,
-					      commit_to_sha1);
-
-			if (edge_value >= 0)
-				edge_value += ctx->new_num_commits_in_base;
-			else {
-				uint32_t pos;
-				if (find_commit_in_graph(parent->item,
-							 ctx->new_base_graph,
-							 &pos))
-					edge_value = pos;
-			}
-
-			if (edge_value < 0)
-				BUG("missing parent %s for commit %s",
-				    oid_to_hex(&parent->item->object.oid),
-				    oid_to_hex(&(*list)->object.oid));
-		}
-
-		hashwrite_be32(f, edge_value);
-
-		if (edge_value & GRAPH_EXTRA_EDGES_NEEDED) {
-			do {
-				num_extra_edges++;
-				parent = parent->next;
-			} while (parent);
-		}
-
-		if (sizeof((*list)->date) > 4)
-			packedDate[0] = htonl(((*list)->date >> 32) & 0x3);
-		else
-			packedDate[0] = 0;
-
-		packedDate[0] |= htonl((*list)->generation << 2);
-
-		packedDate[1] = htonl((*list)->date);
-		hashwrite(f, packedDate, 8);
-
-		list++;
-	}
-}
-
-static void write_graph_chunk_extra_edges(struct hashfile *f,
-					  struct write_commit_graph_context *ctx)
-{
-	struct commit **list = ctx->commits.list;
-	struct commit **last = ctx->commits.list + ctx->commits.nr;
-	struct commit_list *parent;
-
-	while (list < last) {
-		int num_parents = 0;
-
-		display_progress(ctx->progress, ++ctx->progress_cnt);
-
-		for (parent = (*list)->parents; num_parents < 3 && parent;
-		     parent = parent->next)
-			num_parents++;
-
-		if (num_parents <= 2) {
-			list++;
-			continue;
-		}
-
-		/* Since num_parents > 2, this initializer is safe. */
-		for (parent = (*list)->parents->next; parent; parent = parent->next) {
-			int edge_value = sha1_pos(parent->item->object.oid.hash,
-						  ctx->commits.list,
-						  ctx->commits.nr,
-						  commit_to_sha1);
-
-			if (edge_value >= 0)
-				edge_value += ctx->new_num_commits_in_base;
-			else {
-				uint32_t pos;
-				if (find_commit_in_graph(parent->item,
-							 ctx->new_base_graph,
-							 &pos))
-					edge_value = pos;
-			}
-
-			if (edge_value < 0)
-				BUG("missing parent %s for commit %s",
-				    oid_to_hex(&parent->item->object.oid),
-				    oid_to_hex(&(*list)->object.oid));
-			else if (!parent->next)
-				edge_value |= GRAPH_LAST_EDGE;
-
-			hashwrite_be32(f, edge_value);
-		}
-
-		list++;
-	}
-}
-
-static int oid_compare(const void *_a, const void *_b)
-{
-	const struct object_id *a = (const struct object_id *)_a;
-	const struct object_id *b = (const struct object_id *)_b;
-	return oidcmp(a, b);
-}
-
-static int add_packed_commits(const struct object_id *oid,
-			      struct packed_git *pack,
-			      uint32_t pos,
-			      void *data)
-{
-	struct write_commit_graph_context *ctx = (struct write_commit_graph_context*)data;
-	enum object_type type;
-	off_t offset = nth_packed_object_offset(pack, pos);
-	struct object_info oi = OBJECT_INFO_INIT;
-
-	if (ctx->progress)
-		display_progress(ctx->progress, ++ctx->progress_done);
-
-	oi.typep = &type;
-	if (packed_object_info(ctx->r, pack, offset, &oi) < 0)
-		die(_("unable to get type of object %s"), oid_to_hex(oid));
-
-	if (type != OBJ_COMMIT)
-		return 0;
-
-	ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
-	oidcpy(&(ctx->oids.list[ctx->oids.nr]), oid);
-	ctx->oids.nr++;
-
-	return 0;
-}
-
-static void add_missing_parents(struct write_commit_graph_context *ctx, struct commit *commit)
-{
-	struct commit_list *parent;
-	for (parent = commit->parents; parent; parent = parent->next) {
-		if (!(parent->item->object.flags & UNINTERESTING)) {
-			ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
-			oidcpy(&ctx->oids.list[ctx->oids.nr], &(parent->item->object.oid));
-			ctx->oids.nr++;
-			parent->item->object.flags |= UNINTERESTING;
-		}
-	}
-}
-
-static void close_reachable(struct write_commit_graph_context *ctx)
-{
-	int i;
-	struct commit *commit;
-
-	if (ctx->report_progress)
-		ctx->progress = start_delayed_progress(
-					_("Loading known commits in commit graph"),
-					ctx->oids.nr);
-	for (i = 0; i < ctx->oids.nr; i++) {
-		display_progress(ctx->progress, i + 1);
-		commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
-		if (commit)
-			commit->object.flags |= UNINTERESTING;
-	}
-	stop_progress(&ctx->progress);
-
-	/*
-	 * As this loop runs, ctx->oids.nr may grow, but not more
-	 * than the number of missing commits in the reachable
-	 * closure.
-	 */
-	if (ctx->report_progress)
-		ctx->progress = start_delayed_progress(
-					_("Expanding reachable commits in commit graph"),
-					ctx->oids.nr);
-	for (i = 0; i < ctx->oids.nr; i++) {
-		display_progress(ctx->progress, i + 1);
-		commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
-
-		if (!commit)
-			continue;
-		if (ctx->split) {
-			if (!parse_commit(commit) &&
-			    commit->graph_pos == COMMIT_NOT_FROM_GRAPH)
-				add_missing_parents(ctx, commit);
-		} else if (!parse_commit_no_graph(commit))
-			add_missing_parents(ctx, commit);
-	}
-	stop_progress(&ctx->progress);
-
-	if (ctx->report_progress)
-		ctx->progress = start_delayed_progress(
-					_("Clearing commit marks in commit graph"),
-					ctx->oids.nr);
-	for (i = 0; i < ctx->oids.nr; i++) {
-		display_progress(ctx->progress, i + 1);
-		commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
-
-		if (commit)
-			commit->object.flags &= ~UNINTERESTING;
-	}
-	stop_progress(&ctx->progress);
-}
-
-static void compute_generation_numbers(struct write_commit_graph_context *ctx)
-{
-	int i;
-	struct commit_list *list = NULL;
-
-	if (ctx->report_progress)
-		ctx->progress = start_progress(
-					_("Computing commit graph generation numbers"),
-					ctx->commits.nr);
-	for (i = 0; i < ctx->commits.nr; i++) {
-		display_progress(ctx->progress, i + 1);
-		if (ctx->commits.list[i]->generation != GENERATION_NUMBER_INFINITY &&
-		    ctx->commits.list[i]->generation != GENERATION_NUMBER_ZERO)
-			continue;
-
-		commit_list_insert(ctx->commits.list[i], &list);
-		while (list) {
-			struct commit *current = list->item;
-			struct commit_list *parent;
-			int all_parents_computed = 1;
-			uint32_t max_generation = 0;
-
-			for (parent = current->parents; parent; parent = parent->next) {
-				if (parent->item->generation == GENERATION_NUMBER_INFINITY ||
-				    parent->item->generation == GENERATION_NUMBER_ZERO) {
-					all_parents_computed = 0;
-					commit_list_insert(parent->item, &list);
-					break;
-				} else if (parent->item->generation > max_generation) {
-					max_generation = parent->item->generation;
-				}
-			}
-
-			if (all_parents_computed) {
-				current->generation = max_generation + 1;
-				pop_commit(&list);
-
-				if (current->generation > GENERATION_NUMBER_MAX)
-					current->generation = GENERATION_NUMBER_MAX;
-			}
-		}
-	}
-	stop_progress(&ctx->progress);
-}
-
-static int add_ref_to_list(const char *refname,
-			   const struct object_id *oid,
-			   int flags, void *cb_data)
-{
-	struct string_list *list = (struct string_list *)cb_data;
-
-	string_list_append(list, oid_to_hex(oid));
-	return 0;
-}
-
-int write_commit_graph_reachable(const char *obj_dir, unsigned int flags,
-				 const struct split_commit_graph_opts *split_opts)
-{
-	struct string_list list = STRING_LIST_INIT_DUP;
-	int result;
-
-	for_each_ref(add_ref_to_list, &list);
-	result = write_commit_graph(obj_dir, NULL, &list,
-				    flags, split_opts);
-
-	string_list_clear(&list, 0);
-	return result;
-}
-
-static int fill_oids_from_packs(struct write_commit_graph_context *ctx,
-				struct string_list *pack_indexes)
-{
-	uint32_t i;
-	struct strbuf progress_title = STRBUF_INIT;
-	struct strbuf packname = STRBUF_INIT;
-	int dirlen;
-
-	strbuf_addf(&packname, "%s/pack/", ctx->obj_dir);
-	dirlen = packname.len;
-	if (ctx->report_progress) {
-		strbuf_addf(&progress_title,
-			    Q_("Finding commits for commit graph in %d pack",
-			       "Finding commits for commit graph in %d packs",
-			       pack_indexes->nr),
-			    pack_indexes->nr);
-		ctx->progress = start_delayed_progress(progress_title.buf, 0);
-		ctx->progress_done = 0;
-	}
-	for (i = 0; i < pack_indexes->nr; i++) {
-		struct packed_git *p;
-		strbuf_setlen(&packname, dirlen);
-		strbuf_addstr(&packname, pack_indexes->items[i].string);
-		p = add_packed_git(packname.buf, packname.len, 1);
-		if (!p) {
-			error(_("error adding pack %s"), packname.buf);
-			return -1;
-		}
-		if (open_pack_index(p)) {
-			error(_("error opening index for %s"), packname.buf);
-			return -1;
-		}
-		for_each_object_in_pack(p, add_packed_commits, ctx,
-					FOR_EACH_OBJECT_PACK_ORDER);
-		close_pack(p);
-		free(p);
-	}
-
-	stop_progress(&ctx->progress);
-	strbuf_release(&progress_title);
-	strbuf_release(&packname);
-
-	return 0;
-}
-
-static void fill_oids_from_commit_hex(struct write_commit_graph_context *ctx,
-				      struct string_list *commit_hex)
-{
-	uint32_t i;
-	struct strbuf progress_title = STRBUF_INIT;
-
-	if (ctx->report_progress) {
-		strbuf_addf(&progress_title,
-			    Q_("Finding commits for commit graph from %d ref",
-			       "Finding commits for commit graph from %d refs",
-			       commit_hex->nr),
-			    commit_hex->nr);
-		ctx->progress = start_delayed_progress(
-					progress_title.buf,
-					commit_hex->nr);
-	}
-	for (i = 0; i < commit_hex->nr; i++) {
-		const char *end;
-		struct object_id oid;
-		struct commit *result;
-
-		display_progress(ctx->progress, i + 1);
-		if (commit_hex->items[i].string &&
-		    parse_oid_hex(commit_hex->items[i].string, &oid, &end))
-			continue;
-
-		result = lookup_commit_reference_gently(ctx->r, &oid, 1);
-
-		if (result) {
-			ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
-			oidcpy(&ctx->oids.list[ctx->oids.nr], &(result->object.oid));
-			ctx->oids.nr++;
-		}
-	}
-	stop_progress(&ctx->progress);
-	strbuf_release(&progress_title);
-}
-
-static void fill_oids_from_all_packs(struct write_commit_graph_context *ctx)
-{
-	if (ctx->report_progress)
-		ctx->progress = start_delayed_progress(
-			_("Finding commits for commit graph among packed objects"),
-			ctx->approx_nr_objects);
-	for_each_packed_object(add_packed_commits, ctx,
-			       FOR_EACH_OBJECT_PACK_ORDER);
-	if (ctx->progress_done < ctx->approx_nr_objects)
-		display_progress(ctx->progress, ctx->approx_nr_objects);
-	stop_progress(&ctx->progress);
-}
-
-static uint32_t count_distinct_commits(struct write_commit_graph_context *ctx)
-{
-	uint32_t i, count_distinct = 1;
-
-	if (ctx->report_progress)
-		ctx->progress = start_delayed_progress(
-			_("Counting distinct commits in commit graph"),
-			ctx->oids.nr);
-	display_progress(ctx->progress, 0); /* TODO: Measure QSORT() progress */
-	QSORT(ctx->oids.list, ctx->oids.nr, oid_compare);
-
-	for (i = 1; i < ctx->oids.nr; i++) {
-		display_progress(ctx->progress, i + 1);
-		if (!oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i])) {
-			if (ctx->split) {
-				struct commit *c = lookup_commit(ctx->r, &ctx->oids.list[i]);
-
-				if (!c || c->graph_pos != COMMIT_NOT_FROM_GRAPH)
-					continue;
-			}
-
-			count_distinct++;
-		}
-	}
-	stop_progress(&ctx->progress);
-
-	return count_distinct;
-}
-
-static void copy_oids_to_commits(struct write_commit_graph_context *ctx)
-{
-	uint32_t i;
-	struct commit_list *parent;
-
-	ctx->num_extra_edges = 0;
-	if (ctx->report_progress)
-		ctx->progress = start_delayed_progress(
-			_("Finding extra edges in commit graph"),
-			ctx->oids.nr);
-	for (i = 0; i < ctx->oids.nr; i++) {
-		int num_parents = 0;
-		display_progress(ctx->progress, i + 1);
-		if (i > 0 && oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i]))
-			continue;
-
-		ALLOC_GROW(ctx->commits.list, ctx->commits.nr + 1, ctx->commits.alloc);
-		ctx->commits.list[ctx->commits.nr] = lookup_commit(ctx->r, &ctx->oids.list[i]);
-
-		if (ctx->split &&
-		    ctx->commits.list[ctx->commits.nr]->graph_pos != COMMIT_NOT_FROM_GRAPH)
-			continue;
-
-		parse_commit_no_graph(ctx->commits.list[ctx->commits.nr]);
-
-		for (parent = ctx->commits.list[ctx->commits.nr]->parents;
-		     parent; parent = parent->next)
-			num_parents++;
-
-		if (num_parents > 2)
-			ctx->num_extra_edges += num_parents - 1;
-
-		ctx->commits.nr++;
-	}
-	stop_progress(&ctx->progress);
-}
-
-static int write_graph_chunk_base_1(struct hashfile *f,
-				    struct commit_graph *g)
-{
-	int num = 0;
-
-	if (!g)
-		return 0;
-
-	num = write_graph_chunk_base_1(f, g->base_graph);
-	hashwrite(f, g->oid.hash, the_hash_algo->rawsz);
-	return num + 1;
-}
-
-static int write_graph_chunk_base(struct hashfile *f,
-				  struct write_commit_graph_context *ctx)
-{
-	int num = write_graph_chunk_base_1(f, ctx->new_base_graph);
-
-	if (num != ctx->num_commit_graphs_after - 1) {
-		error(_("failed to write correct number of base graph ids"));
-		return -1;
-	}
-
-	return 0;
-}
-
-static int write_commit_graph_file(struct write_commit_graph_context *ctx)
-{
-	uint32_t i;
-	int fd;
-	struct hashfile *f;
-	struct lock_file lk = LOCK_INIT;
-	uint32_t chunk_ids[6];
-	uint64_t chunk_offsets[6];
-	const unsigned hashsz = the_hash_algo->rawsz;
-	struct strbuf progress_title = STRBUF_INIT;
-	int num_chunks = 3;
-	struct object_id file_hash;
-
-	if (ctx->split) {
-		struct strbuf tmp_file = STRBUF_INIT;
-
-		strbuf_addf(&tmp_file,
-			    "%s/info/commit-graphs/tmp_graph_XXXXXX",
-			    ctx->obj_dir);
-		ctx->graph_name = strbuf_detach(&tmp_file, NULL);
-	} else {
-		ctx->graph_name = get_commit_graph_filename(ctx->obj_dir);
-	}
-
-	if (safe_create_leading_directories(ctx->graph_name)) {
-		UNLEAK(ctx->graph_name);
-		error(_("unable to create leading directories of %s"),
-			ctx->graph_name);
-		return -1;
-	}
-
-	if (ctx->split) {
-		char *lock_name = get_chain_filename(ctx->obj_dir);
-
-		hold_lock_file_for_update(&lk, lock_name, LOCK_DIE_ON_ERROR);
-
-		fd = git_mkstemp_mode(ctx->graph_name, 0444);
-		if (fd < 0) {
-			error(_("unable to create '%s'"), ctx->graph_name);
-			return -1;
-		}
-
-		f = hashfd(fd, ctx->graph_name);
-	} else {
-		hold_lock_file_for_update(&lk, ctx->graph_name, LOCK_DIE_ON_ERROR);
-		fd = lk.tempfile->fd;
-		f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
-	}
-
-	chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
-	chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
-	chunk_ids[2] = GRAPH_CHUNKID_DATA;
-	if (ctx->num_extra_edges) {
-		chunk_ids[num_chunks] = GRAPH_CHUNKID_EXTRAEDGES;
-		num_chunks++;
-	}
-	if (ctx->num_commit_graphs_after > 1) {
-		chunk_ids[num_chunks] = GRAPH_CHUNKID_BASE;
-		num_chunks++;
-	}
-
-	chunk_ids[num_chunks] = 0;
-
-	chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
-	chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
-	chunk_offsets[2] = chunk_offsets[1] + hashsz * ctx->commits.nr;
-	chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * ctx->commits.nr;
-
-	num_chunks = 3;
-	if (ctx->num_extra_edges) {
-		chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
-						4 * ctx->num_extra_edges;
-		num_chunks++;
-	}
-	if (ctx->num_commit_graphs_after > 1) {
-		chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
-						hashsz * (ctx->num_commit_graphs_after - 1);
-		num_chunks++;
-	}
-
-	hashwrite_be32(f, GRAPH_SIGNATURE);
-
-	hashwrite_u8(f, GRAPH_VERSION);
-	hashwrite_u8(f, oid_version());
-	hashwrite_u8(f, num_chunks);
-	hashwrite_u8(f, ctx->num_commit_graphs_after - 1);
-
-	for (i = 0; i <= num_chunks; i++) {
-		uint32_t chunk_write[3];
-
-		chunk_write[0] = htonl(chunk_ids[i]);
-		chunk_write[1] = htonl(chunk_offsets[i] >> 32);
-		chunk_write[2] = htonl(chunk_offsets[i] & 0xffffffff);
-		hashwrite(f, chunk_write, 12);
-	}
-
-	if (ctx->report_progress) {
-		strbuf_addf(&progress_title,
-			    Q_("Writing out commit graph in %d pass",
-			       "Writing out commit graph in %d passes",
-			       num_chunks),
-			    num_chunks);
-		ctx->progress = start_delayed_progress(
-			progress_title.buf,
-			num_chunks * ctx->commits.nr);
-	}
-	write_graph_chunk_fanout(f, ctx);
-	write_graph_chunk_oids(f, hashsz, ctx);
-	write_graph_chunk_data(f, hashsz, ctx);
-	if (ctx->num_extra_edges)
-		write_graph_chunk_extra_edges(f, ctx);
-	if (ctx->num_commit_graphs_after > 1 &&
-	    write_graph_chunk_base(f, ctx)) {
-		return -1;
-	}
-	stop_progress(&ctx->progress);
-	strbuf_release(&progress_title);
-
-	if (ctx->split && ctx->base_graph_name && ctx->num_commit_graphs_after > 1) {
-		char *new_base_hash = xstrdup(oid_to_hex(&ctx->new_base_graph->oid));
-		char *new_base_name = get_split_graph_filename(ctx->new_base_graph->obj_dir, new_base_hash);
-
-		free(ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2]);
-		free(ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2]);
-		ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2] = new_base_name;
-		ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2] = new_base_hash;
-	}
-
-	close_commit_graph(ctx->r->objects);
-	finalize_hashfile(f, file_hash.hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
-
-	if (ctx->split) {
-		FILE *chainf = fdopen_lock_file(&lk, "w");
-		char *final_graph_name;
-		int result;
-
-		close(fd);
-
-		if (!chainf) {
-			error(_("unable to open commit-graph chain file"));
-			return -1;
-		}
-
-		if (ctx->base_graph_name) {
-			const char *dest = ctx->commit_graph_filenames_after[
-						ctx->num_commit_graphs_after - 2];
-
-			if (strcmp(ctx->base_graph_name, dest)) {
-				result = rename(ctx->base_graph_name, dest);
-
-				if (result) {
-					error(_("failed to rename base commit-graph file"));
-					return -1;
-				}
-			}
-		} else {
-			char *graph_name = get_commit_graph_filename(ctx->obj_dir);
-			unlink(graph_name);
-		}
-
-		ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1] = xstrdup(oid_to_hex(&file_hash));
-		final_graph_name = get_split_graph_filename(ctx->obj_dir,
-					ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1]);
-		ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 1] = final_graph_name;
-
-		result = rename(ctx->graph_name, final_graph_name);
-
-		for (i = 0; i < ctx->num_commit_graphs_after; i++)
-			fprintf(lk.tempfile->fp, "%s\n", ctx->commit_graph_hash_after[i]);
-
-		if (result) {
-			error(_("failed to rename temporary commit-graph file"));
-			return -1;
-		}
-	}
-
-	commit_lock_file(&lk);
-
-	return 0;
-}
-
-static void split_graph_merge_strategy(struct write_commit_graph_context *ctx)
-{
-	struct commit_graph *g = ctx->r->objects->commit_graph;
-	uint32_t num_commits = ctx->commits.nr;
-	uint32_t i;
-
-	int max_commits = 0;
-	int size_mult = 2;
-
-	if (ctx->split_opts) {
-		max_commits = ctx->split_opts->max_commits;
-		size_mult = ctx->split_opts->size_multiple;
-	}
-
-	g = ctx->r->objects->commit_graph;
-	ctx->num_commit_graphs_after = ctx->num_commit_graphs_before + 1;
-
-	while (g && (g->num_commits <= size_mult * num_commits ||
-		    (max_commits && num_commits > max_commits))) {
-		if (strcmp(g->obj_dir, ctx->obj_dir))
-			break;
-
-		num_commits += g->num_commits;
-		g = g->base_graph;
-
-		ctx->num_commit_graphs_after--;
-	}
-
-	ctx->new_base_graph = g;
-
-	if (ctx->num_commit_graphs_after == 2) {
-		char *old_graph_name = get_commit_graph_filename(g->obj_dir);
-
-		if (!strcmp(g->filename, old_graph_name) &&
-		    strcmp(g->obj_dir, ctx->obj_dir)) {
-			ctx->num_commit_graphs_after = 1;
-			ctx->new_base_graph = NULL;
-		}
-
-		free(old_graph_name);
-	}
-
-	ALLOC_ARRAY(ctx->commit_graph_filenames_after, ctx->num_commit_graphs_after);
-	ALLOC_ARRAY(ctx->commit_graph_hash_after, ctx->num_commit_graphs_after);
-
-	for (i = 0; i < ctx->num_commit_graphs_after &&
-		    i < ctx->num_commit_graphs_before; i++)
-		ctx->commit_graph_filenames_after[i] = xstrdup(ctx->commit_graph_filenames_before[i]);
-
-	i = ctx->num_commit_graphs_before - 1;
-	g = ctx->r->objects->commit_graph;
-
-	while (g) {
-		if (i < ctx->num_commit_graphs_after)
-			ctx->commit_graph_hash_after[i] = xstrdup(oid_to_hex(&g->oid));
-
-		i--;
-		g = g->base_graph;
-	}
-}
-
-static void merge_commit_graph(struct write_commit_graph_context *ctx,
-			       struct commit_graph *g)
-{
-	uint32_t i;
-	uint32_t offset = g->num_commits_in_base;
-
-	ALLOC_GROW(ctx->commits.list, ctx->commits.nr + g->num_commits, ctx->commits.alloc);
-
-	for (i = 0; i < g->num_commits; i++) {
-		struct object_id oid;
-		struct commit *result;
-
-		display_progress(ctx->progress, i + 1);
-
-		load_oid_from_graph(g, i + offset, &oid);
-
-		/* only add commits if they still exist in the repo */
-		result = lookup_commit_reference_gently(ctx->r, &oid, 1);
-
-		if (result) {
-			ctx->commits.list[ctx->commits.nr] = result;
-			ctx->commits.nr++;
-		}
-	}
-}
-
-static int commit_compare(const void *_a, const void *_b)
-{
-	const struct commit *a = *(const struct commit **)_a;
-	const struct commit *b = *(const struct commit **)_b;
-	return oidcmp(&a->object.oid, &b->object.oid);
-}
-
-static void sort_and_scan_merged_commits(struct write_commit_graph_context *ctx)
-{
-	uint32_t i, num_parents;
-	struct commit_list *parent;
-
-	if (ctx->report_progress)
-		ctx->progress = start_delayed_progress(
-					_("Scanning merged commits"),
-					ctx->commits.nr);
-
-	QSORT(ctx->commits.list, ctx->commits.nr, commit_compare);
-
-	ctx->num_extra_edges = 0;
-	for (i = 0; i < ctx->commits.nr; i++) {
-		display_progress(ctx->progress, i);
-
-		if (i && oideq(&ctx->commits.list[i - 1]->object.oid,
-			  &ctx->commits.list[i]->object.oid)) {
-			die(_("unexpected duplicate commit id %s"),
-			    oid_to_hex(&ctx->commits.list[i]->object.oid));
-		} else {
-			num_parents = 0;
-			for (parent = ctx->commits.list[i]->parents; parent; parent = parent->next)
-				num_parents++;
-
-			if (num_parents > 2)
-				ctx->num_extra_edges += num_parents - 1;
-		}
-	}
-
-	stop_progress(&ctx->progress);
-}
-
-static void merge_commit_graphs(struct write_commit_graph_context *ctx)
-{
-	struct commit_graph *g = ctx->r->objects->commit_graph;
-	uint32_t current_graph_number = ctx->num_commit_graphs_before;
-	struct strbuf progress_title = STRBUF_INIT;
-
-	while (g && current_graph_number >= ctx->num_commit_graphs_after) {
-		current_graph_number--;
-
-		if (ctx->report_progress) {
-			strbuf_addstr(&progress_title, _("Merging commit-graph"));
-			ctx->progress = start_delayed_progress(progress_title.buf, 0);
-		}
-
-		merge_commit_graph(ctx, g);
-		stop_progress(&ctx->progress);
-		strbuf_release(&progress_title);
-
-		g = g->base_graph;
-	}
-
-	if (g) {
-		ctx->new_base_graph = g;
-		ctx->new_num_commits_in_base = g->num_commits + g->num_commits_in_base;
-	}
-
-	if (ctx->new_base_graph)
-		ctx->base_graph_name = xstrdup(ctx->new_base_graph->filename);
-
-	sort_and_scan_merged_commits(ctx);
-}
-
-static void mark_commit_graphs(struct write_commit_graph_context *ctx)
-{
-	uint32_t i;
-	time_t now = time(NULL);
-
-	for (i = ctx->num_commit_graphs_after - 1; i < ctx->num_commit_graphs_before; i++) {
-		struct stat st;
-		struct utimbuf updated_time;
-
-		stat(ctx->commit_graph_filenames_before[i], &st);
-
-		updated_time.actime = st.st_atime;
-		updated_time.modtime = now;
-		utime(ctx->commit_graph_filenames_before[i], &updated_time);
-	}
-}
-
-static void expire_commit_graphs(struct write_commit_graph_context *ctx)
-{
-	struct strbuf path = STRBUF_INIT;
-	DIR *dir;
-	struct dirent *de;
-	size_t dirnamelen;
-	timestamp_t expire_time = time(NULL);
-
-	if (ctx->split_opts && ctx->split_opts->expire_time)
-		expire_time -= ctx->split_opts->expire_time;
-	if (!ctx->split) {
-		char *chain_file_name = get_chain_filename(ctx->obj_dir);
-		unlink(chain_file_name);
-		free(chain_file_name);
-		ctx->num_commit_graphs_after = 0;
-	}
-
-	strbuf_addstr(&path, ctx->obj_dir);
-	strbuf_addstr(&path, "/info/commit-graphs");
-	dir = opendir(path.buf);
-
-	if (!dir)
-		goto out;
-
-	strbuf_addch(&path, '/');
-	dirnamelen = path.len;
-	while ((de = readdir(dir)) != NULL) {
-		struct stat st;
-		uint32_t i, found = 0;
-
-		strbuf_setlen(&path, dirnamelen);
-		strbuf_addstr(&path, de->d_name);
-
-		stat(path.buf, &st);
-
-		if (st.st_mtime > expire_time)
-			continue;
-		if (path.len < 6 || strcmp(path.buf + path.len - 6, ".graph"))
-			continue;
-
-		for (i = 0; i < ctx->num_commit_graphs_after; i++) {
-			if (!strcmp(ctx->commit_graph_filenames_after[i],
-				    path.buf)) {
-				found = 1;
-				break;
-			}
-		}
-
-		if (!found)
-			unlink(path.buf);
-	}
-
-out:
-	strbuf_release(&path);
-}
-
-int write_commit_graph(const char *obj_dir,
-		       struct string_list *pack_indexes,
-		       struct string_list *commit_hex,
-		       unsigned int flags,
-		       const struct split_commit_graph_opts *split_opts)
-{
-	struct write_commit_graph_context *ctx;
-	uint32_t i, count_distinct = 0;
-	size_t len;
-	int res = 0;
-
-	if (!commit_graph_compatible(the_repository))
-		return 0;
-
-	ctx = xcalloc(1, sizeof(struct write_commit_graph_context));
-	ctx->r = the_repository;
-
-	/* normalize object dir with no trailing slash */
-	ctx->obj_dir = xmallocz(strlen(obj_dir) + 1);
-	normalize_path_copy(ctx->obj_dir, obj_dir);
-	len = strlen(ctx->obj_dir);
-	if (len && ctx->obj_dir[len - 1] == '/')
-		ctx->obj_dir[len - 1] = 0;
-
-	ctx->append = flags & COMMIT_GRAPH_APPEND ? 1 : 0;
-	ctx->report_progress = flags & COMMIT_GRAPH_PROGRESS ? 1 : 0;
-	ctx->split = flags & COMMIT_GRAPH_SPLIT ? 1 : 0;
-	ctx->split_opts = split_opts;
-
-	if (ctx->split) {
-		struct commit_graph *g;
-		prepare_commit_graph(ctx->r);
-
-		g = ctx->r->objects->commit_graph;
-
-		while (g) {
-			ctx->num_commit_graphs_before++;
-			g = g->base_graph;
-		}
-
-		if (ctx->num_commit_graphs_before) {
-			ALLOC_ARRAY(ctx->commit_graph_filenames_before, ctx->num_commit_graphs_before);
-			i = ctx->num_commit_graphs_before;
-			g = ctx->r->objects->commit_graph;
-
-			while (g) {
-				ctx->commit_graph_filenames_before[--i] = xstrdup(g->filename);
-				g = g->base_graph;
-			}
-		}
-	}
-
-	ctx->approx_nr_objects = approximate_object_count();
-	ctx->oids.alloc = ctx->approx_nr_objects / 32;
-
-	if (ctx->split && split_opts && ctx->oids.alloc > split_opts->max_commits)
-		ctx->oids.alloc = split_opts->max_commits;
-
-	if (ctx->append) {
-		prepare_commit_graph_one(ctx->r, ctx->obj_dir);
-		if (ctx->r->objects->commit_graph)
-			ctx->oids.alloc += ctx->r->objects->commit_graph->num_commits;
-	}
-
-	if (ctx->oids.alloc < 1024)
-		ctx->oids.alloc = 1024;
-	ALLOC_ARRAY(ctx->oids.list, ctx->oids.alloc);
-
-	if (ctx->append && ctx->r->objects->commit_graph) {
-		struct commit_graph *g = ctx->r->objects->commit_graph;
-		for (i = 0; i < g->num_commits; i++) {
-			const unsigned char *hash = g->chunk_oid_lookup + g->hash_len * i;
-			hashcpy(ctx->oids.list[ctx->oids.nr++].hash, hash);
-		}
-	}
-
-	if (pack_indexes) {
-		if ((res = fill_oids_from_packs(ctx, pack_indexes)))
-			goto cleanup;
-	}
-
-	if (commit_hex)
-		fill_oids_from_commit_hex(ctx, commit_hex);
-
-	if (!pack_indexes && !commit_hex)
-		fill_oids_from_all_packs(ctx);
-
-	close_reachable(ctx);
-
-	count_distinct = count_distinct_commits(ctx);
-
-	if (count_distinct >= GRAPH_EDGE_LAST_MASK) {
-		error(_("the commit graph format cannot write %d commits"), count_distinct);
-		res = -1;
-		goto cleanup;
-	}
-
-	ctx->commits.alloc = count_distinct;
-	ALLOC_ARRAY(ctx->commits.list, ctx->commits.alloc);
-
-	copy_oids_to_commits(ctx);
-
-	if (ctx->commits.nr >= GRAPH_EDGE_LAST_MASK) {
-		error(_("too many commits to write graph"));
-		res = -1;
-		goto cleanup;
-	}
-
-	if (!ctx->commits.nr)
-		goto cleanup;
-
-	if (ctx->split) {
-		split_graph_merge_strategy(ctx);
-
-		merge_commit_graphs(ctx);
-	} else
-		ctx->num_commit_graphs_after = 1;
-
-	compute_generation_numbers(ctx);
-
-	res = write_commit_graph_file(ctx);
-
-	if (ctx->split)
-		mark_commit_graphs(ctx);
-
-	expire_commit_graphs(ctx);
-
-cleanup:
-	free(ctx->graph_name);
-	free(ctx->commits.list);
-	free(ctx->oids.list);
-	free(ctx->obj_dir);
-
-	if (ctx->commit_graph_filenames_after) {
-		for (i = 0; i < ctx->num_commit_graphs_after; i++) {
-			free(ctx->commit_graph_filenames_after[i]);
-			free(ctx->commit_graph_hash_after[i]);
-		}
-
-		for (i = 0; i < ctx->num_commit_graphs_before; i++)
-			free(ctx->commit_graph_filenames_before[i]);
-
-		free(ctx->commit_graph_filenames_after);
-		free(ctx->commit_graph_filenames_before);
-		free(ctx->commit_graph_hash_after);
-	}
-
-	free(ctx);
-
-	return res;
-}
-
-#define VERIFY_COMMIT_GRAPH_ERROR_HASH 2
-static int verify_commit_graph_error;
-
-static void graph_report(const char *fmt, ...)
-{
-	va_list ap;
-
-	verify_commit_graph_error = 1;
-	va_start(ap, fmt);
-	vfprintf(stderr, fmt, ap);
-	fprintf(stderr, "\n");
-	va_end(ap);
-}
-
-#define GENERATION_ZERO_EXISTS 1
-#define GENERATION_NUMBER_EXISTS 2
-
-int verify_commit_graph(struct repository *r, struct commit_graph *g, int flags)
-{
-	uint32_t i, cur_fanout_pos = 0;
-	struct object_id prev_oid, cur_oid, checksum;
-	int generation_zero = 0;
-	struct hashfile *f;
-	int devnull;
-	struct progress *progress = NULL;
-	int local_error = 0;
-
-	if (!g) {
-		graph_report("no commit-graph file loaded");
-		return 1;
-	}
-
-	verify_commit_graph_error = verify_commit_graph_lite(g);
-	if (verify_commit_graph_error)
-		return verify_commit_graph_error;
-
-	devnull = open("/dev/null", O_WRONLY);
-	f = hashfd(devnull, NULL);
-	hashwrite(f, g->data, g->data_len - g->hash_len);
-	finalize_hashfile(f, checksum.hash, CSUM_CLOSE);
-	if (!hasheq(checksum.hash, g->data + g->data_len - g->hash_len)) {
-		graph_report(_("the commit-graph file has incorrect checksum and is likely corrupt"));
-		verify_commit_graph_error = VERIFY_COMMIT_GRAPH_ERROR_HASH;
-	}
-
-	for (i = 0; i < g->num_commits; i++) {
-		struct commit *graph_commit;
-
-		hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
-
-		if (i && oidcmp(&prev_oid, &cur_oid) >= 0)
-			graph_report(_("commit-graph has incorrect OID order: %s then %s"),
-				     oid_to_hex(&prev_oid),
-				     oid_to_hex(&cur_oid));
-
-		oidcpy(&prev_oid, &cur_oid);
-
-		while (cur_oid.hash[0] > cur_fanout_pos) {
-			uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
-
-			if (i != fanout_value)
-				graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
-					     cur_fanout_pos, fanout_value, i);
-			cur_fanout_pos++;
-		}
-
-		graph_commit = lookup_commit(r, &cur_oid);
-		if (!parse_commit_in_graph_one(r, g, graph_commit))
-			graph_report(_("failed to parse commit %s from commit-graph"),
-				     oid_to_hex(&cur_oid));
-	}
-
-	while (cur_fanout_pos < 256) {
-		uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
-
-		if (g->num_commits != fanout_value)
-			graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
-				     cur_fanout_pos, fanout_value, i);
-
-		cur_fanout_pos++;
-	}
-
-	if (verify_commit_graph_error & ~VERIFY_COMMIT_GRAPH_ERROR_HASH)
-		return verify_commit_graph_error;
-
-	progress = start_progress(_("Verifying commits in commit graph"),
-				  g->num_commits);
-	for (i = 0; i < g->num_commits; i++) {
-		struct commit *graph_commit, *odb_commit;
-		struct commit_list *graph_parents, *odb_parents;
-		uint32_t max_generation = 0;
-
-		display_progress(progress, i + 1);
-		hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
-
-		graph_commit = lookup_commit(r, &cur_oid);
-		odb_commit = (struct commit *)create_object(r, &cur_oid, alloc_commit_node(r));
-		if (parse_commit_internal(odb_commit, 0, 0)) {
-			graph_report(_("failed to parse commit %s from object database for commit-graph"),
-				     oid_to_hex(&cur_oid));
-			continue;
-		}
-
-		if (!oideq(&get_commit_tree_in_graph_one(r, g, graph_commit)->object.oid,
-			   get_commit_tree_oid(odb_commit)))
-			graph_report(_("root tree OID for commit %s in commit-graph is %s != %s"),
-				     oid_to_hex(&cur_oid),
-				     oid_to_hex(get_commit_tree_oid(graph_commit)),
-				     oid_to_hex(get_commit_tree_oid(odb_commit)));
-
-		graph_parents = graph_commit->parents;
-		odb_parents = odb_commit->parents;
-
-		while (graph_parents) {
-			if (odb_parents == NULL) {
-				graph_report(_("commit-graph parent list for commit %s is too long"),
-					     oid_to_hex(&cur_oid));
-				break;
-			}
-
-			/* parse parent in case it is in a base graph */
-			parse_commit_in_graph_one(r, g, graph_parents->item);
-
-			if (!oideq(&graph_parents->item->object.oid, &odb_parents->item->object.oid))
-				graph_report(_("commit-graph parent for %s is %s != %s"),
-					     oid_to_hex(&cur_oid),
-					     oid_to_hex(&graph_parents->item->object.oid),
-					     oid_to_hex(&odb_parents->item->object.oid));
-
-			if (graph_parents->item->generation > max_generation)
-				max_generation = graph_parents->item->generation;
-
-			graph_parents = graph_parents->next;
-			odb_parents = odb_parents->next;
-		}
-
-		if (odb_parents != NULL)
-			graph_report(_("commit-graph parent list for commit %s terminates early"),
-				     oid_to_hex(&cur_oid));
-
-		if (!graph_commit->generation) {
-			if (generation_zero == GENERATION_NUMBER_EXISTS)
-				graph_report(_("commit-graph has generation number zero for commit %s, but non-zero elsewhere"),
-					     oid_to_hex(&cur_oid));
-			generation_zero = GENERATION_ZERO_EXISTS;
-		} else if (generation_zero == GENERATION_ZERO_EXISTS)
-			graph_report(_("commit-graph has non-zero generation number for commit %s, but zero elsewhere"),
-				     oid_to_hex(&cur_oid));
-
-		if (generation_zero == GENERATION_ZERO_EXISTS)
-			continue;
-
-		/*
-		 * If one of our parents has generation GENERATION_NUMBER_MAX, then
-		 * our generation is also GENERATION_NUMBER_MAX. Decrement to avoid
-		 * extra logic in the following condition.
-		 */
-		if (max_generation == GENERATION_NUMBER_MAX)
-			max_generation--;
-
-		if (graph_commit->generation != max_generation + 1)
-			graph_report(_("commit-graph generation for commit %s is %u != %u"),
-				     oid_to_hex(&cur_oid),
-				     graph_commit->generation,
-				     max_generation + 1);
-
-		if (graph_commit->date != odb_commit->date)
-			graph_report(_("commit date for commit %s in commit-graph is %"PRItime" != %"PRItime),
-				     oid_to_hex(&cur_oid),
-				     graph_commit->date,
-				     odb_commit->date);
-	}
-	stop_progress(&progress);
-
-	local_error = verify_commit_graph_error;
-
-	if (!(flags & COMMIT_GRAPH_VERIFY_SHALLOW) && g->base_graph)
-		local_error |= verify_commit_graph(r, g->base_graph, flags);
-
-	return local_error;
-}
-
-void free_commit_graph(struct commit_graph *g)
-{
-	if (!g)
-		return;
-	if (g->graph_fd >= 0) {
-		munmap((void *)g->data, g->data_len);
-		g->data = NULL;
-		close(g->graph_fd);
-	}
-	free(g->filename);
-	free(g);
-}