[PATCH 08/11] pack-objects: create pack v4 tables

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 builtin/pack-objects.c | 87 ++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 85 insertions(+), 2 deletions(-)

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index b38d3dc..69a22c1 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -18,6 +18,7 @@
 #include "refs.h"
 #include "streaming.h"
 #include "thread-utils.h"
+#include "packv4-create.h"
 
 static const char *pack_usage[] = {
 	N_("git pack-objects --stdout [options...] [< ref-list | < object-list]"),
@@ -61,6 +62,8 @@ static struct object_entry *objects;
 static struct pack_idx_entry **written_list;
 static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
 
+static struct packv4_tables v4;
+
 static int non_empty;
 static int reuse_delta = 1, reuse_object = 1;
 static int keep_unreachable, unpack_unreachable, include_tag;
@@ -2039,12 +2042,42 @@ static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, vo
 	return 0;
 }
 
+static int sha1_idx_sort(const void *a_, const void *b_)
+{
+	const struct pack_idx_entry *a = a_;
+	const struct pack_idx_entry *b = b_;
+	return hashcmp(a->sha1, b->sha1);
+}
+
+static void prepare_sha1_table(void)
+{
+	unsigned i;
+	/*
+	 * This table includes SHA-1s that may not be present in the
+	 * pack. One of the use of such SHA-1 is for completing thin
+	 * packs, where index-pack does not need to add SHA-1 to the
+	 * table at completion time.
+	 */
+	v4.all_objs = xmalloc(nr_objects * sizeof(*v4.all_objs));
+	v4.all_objs_nr = nr_objects;
+	for (i = 0; i < nr_objects; i++)
+		v4.all_objs[i] = objects[i].idx;
+	qsort(v4.all_objs, nr_objects, sizeof(*v4.all_objs),
+	      sha1_idx_sort);
+}
+
 static void prepare_pack(int window, int depth)
 {
 	struct object_entry **delta_list;
 	uint32_t i, nr_deltas;
 	unsigned n;
 
+	if (pack_version == 4) {
+		sort_dict_entries_by_hits(v4.commit_ident_table);
+		sort_dict_entries_by_hits(v4.tree_path_table);
+		prepare_sha1_table();
+	}
+
 	get_object_details();
 
 	/*
@@ -2191,6 +2224,34 @@ static void read_object_list_from_stdin(void)
 
 		add_preferred_base_object(line+41);
 		add_object_entry(sha1, 0, line+41, 0);
+
+		if (pack_version == 4) {
+			void *data;
+			enum object_type type;
+			unsigned long size;
+			int (*add_dict_entries)(struct dict_table *, void *, unsigned long);
+			struct dict_table *dict;
+
+			switch (sha1_object_info(sha1, &size)) {
+			case OBJ_COMMIT:
+				add_dict_entries = add_commit_dict_entries;
+				dict = v4.commit_ident_table;
+				break;
+			case OBJ_TREE:
+				add_dict_entries = add_tree_dict_entries;
+				dict = v4.tree_path_table;
+				break;
+			default:
+				continue;
+			}
+			data = read_sha1_file(sha1, &type, &size);
+			if (!data)
+				die("cannot unpack %s", sha1_to_hex(sha1));
+			if (add_dict_entries(dict, data, size) < 0)
+				die("can't process %s object %s",
+				    typename(type), sha1_to_hex(sha1));
+			free(data);
+		}
 	}
 }
 
@@ -2198,10 +2259,26 @@ static void read_object_list_from_stdin(void)
 
 static void show_commit(struct commit *commit, void *data)
 {
+	if (pack_version == 4) {
+		unsigned long size;
+		enum object_type type;
+		unsigned char *buf;
+
+		/* commit->buffer is NULL most of the time, don't bother */
+		buf = read_sha1_file(commit->object.sha1, &type, &size);
+		add_commit_dict_entries(v4.commit_ident_table, buf, size);
+		free(buf);
+	}
 	add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
 	commit->object.flags |= OBJECT_ADDED;
 }
 
+static void show_tree_entry(const struct name_entry *entry, void *data)
+{
+	dict_add_entry(v4.tree_path_table, entry->mode, entry->path,
+		       tree_entry_len(entry));
+}
+
 static void show_object(struct object *obj,
 			const struct name_path *path, const char *last,
 			void *data)
@@ -2380,7 +2457,9 @@ static void get_object_list(int ac, const char **av)
 	if (prepare_revision_walk(&revs))
 		die("revision walk setup failed");
 	mark_edges_uninteresting(revs.commits, &revs, show_edge);
-	traverse_commit_list(&revs, show_commit, NULL, show_object, NULL);
+	traverse_commit_list(&revs, show_commit,
+			     pack_version == 4 ? show_tree_entry : NULL,
+			     show_object, NULL);
 
 	if (keep_unreachable)
 		add_objects_in_unpacked_packs(&revs);
@@ -2527,7 +2606,7 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 	}
 	if (pack_to_stdout != !base_name || argc)
 		usage_with_options(pack_usage, pack_objects_options);
-	if (pack_version != 2)
+	if (pack_version != 2 && pack_version != 4)
 		die(_("pack version %d is not supported"), pack_version);
 
 	rp_av[rp_ac++] = "pack-objects";
@@ -2579,6 +2658,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 		progress = 2;
 
 	prepare_packed_git();
+	if (pack_version == 4) {
+		v4.commit_ident_table = create_dict_table();
+		v4.tree_path_table = create_dict_table();
+	}
 
 	if (progress)
 		progress_state = start_progress("Counting objects", 0);
-- 
1.8.2.83.gc99314b