mirror of
https://github.com/git/git
synced 2024-08-27 11:39:22 +00:00
![Taylor Blau](/assets/img/avatar_default.png)
When writing a new pack with a bitmap, it is sometimes convenient to indicate some reference prefixes which should receive priority when selecting which commits to receive bitmaps. A truly motivated caller could accomplish this by setting 'pack.islandCore', (since all commits in the core island are similarly marked as preferred) but this requires callers to opt into using delta islands, which they may or may not want to do. Introduce a new multi-valued configuration, 'pack.preferBitmapTips' to allow callers to specify a list of reference prefixes. All references which have a prefix contained in 'pack.preferBitmapTips' will mark their tips as "preferred" in the same way as commits are marked as preferred for selection by 'pack.islandCore'. The choice of the verb "prefer" is intentional: marking the NEEDS_BITMAP flag on an object does *not* guarantee that that object will receive a bitmap. It merely guarantees that that commit will receive a bitmap over any *other* commit in the same window by bitmap_writer_select_commits(). The test this patch adds reflects this quirk, too. It only tests that a commit (which didn't receive bitmaps by default) is selected for bitmaps after changing the value of 'pack.preferBitmapTips' to include it. Other commits may lose their bitmaps as a byproduct of how the selection process works (bitmap_writer_select_commits() ignores the remainder of a window after seeing a commit with the NEEDS_BITMAP flag). This configuration will aide in selecting important references for multi-pack bitmaps, since they do not respect the same pack.islandCore configuration. (They could, but doing so may be confusing, since it is packs--not bitmaps--which are influenced by the delta-islands configuration). In a fork network repository (one which lists all forks of a given repository as remotes), for example, it is useful to set pack.preferBitmapTips to 'refs/remotes/<root>/heads' and 'refs/remotes/<root>/tags', where '<root>' is an opaque identifier referring to the repository which is at the base of the fork chain. Suggested-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
98 lines
3.1 KiB
C
98 lines
3.1 KiB
C
#ifndef PACK_BITMAP_H
|
|
#define PACK_BITMAP_H
|
|
|
|
#include "ewah/ewok.h"
|
|
#include "khash.h"
|
|
#include "pack.h"
|
|
#include "pack-objects.h"
|
|
#include "string-list.h"
|
|
|
|
struct commit;
|
|
struct repository;
|
|
struct rev_info;
|
|
struct list_objects_filter_options;
|
|
|
|
static const char BITMAP_IDX_SIGNATURE[] = {'B', 'I', 'T', 'M'};
|
|
|
|
struct bitmap_disk_header {
|
|
char magic[ARRAY_SIZE(BITMAP_IDX_SIGNATURE)];
|
|
uint16_t version;
|
|
uint16_t options;
|
|
uint32_t entry_count;
|
|
unsigned char checksum[GIT_MAX_RAWSZ];
|
|
};
|
|
|
|
#define NEEDS_BITMAP (1u<<22)
|
|
|
|
enum pack_bitmap_opts {
|
|
BITMAP_OPT_FULL_DAG = 1,
|
|
BITMAP_OPT_HASH_CACHE = 4,
|
|
};
|
|
|
|
enum pack_bitmap_flags {
|
|
BITMAP_FLAG_REUSE = 0x1
|
|
};
|
|
|
|
typedef int (*show_reachable_fn)(
|
|
const struct object_id *oid,
|
|
enum object_type type,
|
|
int flags,
|
|
uint32_t hash,
|
|
struct packed_git *found_pack,
|
|
off_t found_offset);
|
|
|
|
struct bitmap_index;
|
|
|
|
struct bitmap_index *prepare_bitmap_git(struct repository *r);
|
|
void count_bitmap_commit_list(struct bitmap_index *, uint32_t *commits,
|
|
uint32_t *trees, uint32_t *blobs, uint32_t *tags);
|
|
void traverse_bitmap_commit_list(struct bitmap_index *,
|
|
struct rev_info *revs,
|
|
show_reachable_fn show_reachable);
|
|
void test_bitmap_walk(struct rev_info *revs);
|
|
int test_bitmap_commits(struct repository *r);
|
|
struct bitmap_index *prepare_bitmap_walk(struct rev_info *revs,
|
|
struct list_objects_filter_options *filter);
|
|
int reuse_partial_packfile_from_bitmap(struct bitmap_index *,
|
|
struct packed_git **packfile,
|
|
uint32_t *entries,
|
|
struct bitmap **reuse_out);
|
|
int rebuild_existing_bitmaps(struct bitmap_index *, struct packing_data *mapping,
|
|
kh_oid_map_t *reused_bitmaps, int show_progress);
|
|
void free_bitmap_index(struct bitmap_index *);
|
|
int bitmap_walk_contains(struct bitmap_index *,
|
|
struct bitmap *bitmap, const struct object_id *oid);
|
|
|
|
/*
|
|
* After a traversal has been performed by prepare_bitmap_walk(), this can be
|
|
* queried to see if a particular object was reachable from any of the
|
|
* objects flagged as UNINTERESTING.
|
|
*/
|
|
int bitmap_has_oid_in_uninteresting(struct bitmap_index *, const struct object_id *oid);
|
|
|
|
off_t get_disk_usage_from_bitmap(struct bitmap_index *, struct rev_info *);
|
|
|
|
void bitmap_writer_show_progress(int show);
|
|
void bitmap_writer_set_checksum(unsigned char *sha1);
|
|
void bitmap_writer_build_type_index(struct packing_data *to_pack,
|
|
struct pack_idx_entry **index,
|
|
uint32_t index_nr);
|
|
uint32_t *create_bitmap_mapping(struct bitmap_index *bitmap_git,
|
|
struct packing_data *mapping);
|
|
int rebuild_bitmap(const uint32_t *reposition,
|
|
struct ewah_bitmap *source,
|
|
struct bitmap *dest);
|
|
struct ewah_bitmap *bitmap_for_commit(struct bitmap_index *bitmap_git,
|
|
struct commit *commit);
|
|
void bitmap_writer_select_commits(struct commit **indexed_commits,
|
|
unsigned int indexed_commits_nr, int max_bitmaps);
|
|
void bitmap_writer_build(struct packing_data *to_pack);
|
|
void bitmap_writer_finish(struct pack_idx_entry **index,
|
|
uint32_t index_nr,
|
|
const char *filename,
|
|
uint16_t options);
|
|
|
|
const struct string_list *bitmap_preferred_tips(struct repository *r);
|
|
|
|
#endif
|