git-commit-vandalism/packfile.h
Jeff Hostetler 5ae18df9d8 midx: during verify group objects by packfile to speed verification
Teach `multi-pack-index verify` to sort the set of object by
packfile so that only one packfile needs to be open at a time.

This is a performance improvement.  Previously, objects were
verified in OID order.  This essentially requires all packfiles
to be open at the same time.  If the number of packfiles exceeds
the open file limit, packfiles would be LRU-closed and re-opened
many times.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-03-22 14:31:11 +09:00

183 lines
6.6 KiB
C

#ifndef PACKFILE_H
#define PACKFILE_H
#include "cache.h"
#include "oidset.h"
/* in object-store.h */
struct packed_git;
struct object_info;
/*
* Generate the filename to be used for a pack file with checksum "sha1" and
* extension "ext". The result is written into the strbuf "buf", overwriting
* any existing contents. A pointer to buf->buf is returned as a convenience.
*
* Example: odb_pack_name(out, sha1, "idx") => ".git/objects/pack/pack-1234..idx"
*/
extern char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, const char *ext);
/*
* Return the name of the (local) packfile with the specified sha1 in
* its name. The return value is a pointer to memory that is
* overwritten each time this function is called.
*/
extern char *sha1_pack_name(const unsigned char *sha1);
/*
* Return the name of the (local) pack index file with the specified
* sha1 in its name. The return value is a pointer to memory that is
* overwritten each time this function is called.
*/
extern char *sha1_pack_index_name(const unsigned char *sha1);
extern struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
typedef void each_file_in_pack_dir_fn(const char *full_path, size_t full_path_len,
const char *file_pach, void *data);
void for_each_file_in_pack_dir(const char *objdir,
each_file_in_pack_dir_fn fn,
void *data);
/* A hook to report invalid files in pack directory */
#define PACKDIR_FILE_PACK 1
#define PACKDIR_FILE_IDX 2
#define PACKDIR_FILE_GARBAGE 4
extern void (*report_garbage)(unsigned seen_bits, const char *path);
extern void reprepare_packed_git(struct repository *r);
extern void install_packed_git(struct repository *r, struct packed_git *pack);
struct packed_git *get_packed_git(struct repository *r);
struct list_head *get_packed_git_mru(struct repository *r);
struct multi_pack_index *get_multi_pack_index(struct repository *r);
struct packed_git *get_all_packs(struct repository *r);
/*
* Give a rough count of objects in the repository. This sacrifices accuracy
* for speed.
*/
unsigned long approximate_object_count(void);
extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
struct packed_git *packs);
extern void pack_report(void);
/*
* mmap the index file for the specified packfile (if it is not
* already mmapped). Return 0 on success.
*/
extern int open_pack_index(struct packed_git *);
/*
* munmap the index file for the specified packfile (if it is
* currently mmapped).
*/
extern void close_pack_index(struct packed_git *);
int close_pack_fd(struct packed_git *p);
extern uint32_t get_pack_fanout(struct packed_git *p, uint32_t value);
extern unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
extern void close_pack_windows(struct packed_git *);
extern void close_pack(struct packed_git *);
extern void close_all_packs(struct raw_object_store *o);
extern void unuse_pack(struct pack_window **);
extern void clear_delta_base_cache(void);
extern struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
/*
* Make sure that a pointer access into an mmap'd index file is within bounds,
* and can provide at least 8 bytes of data.
*
* Note that this is only necessary for variable-length segments of the file
* (like the 64-bit extended offset table), as we compare the size to the
* fixed-length parts when we open the file.
*/
extern void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
/*
* Perform binary search on a pack-index for a given oid. Packfile is expected to
* have a valid pack-index.
*
* See 'bsearch_hash' for more information.
*/
int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result);
/*
* Return the SHA-1 of the nth object within the specified packfile.
* Open the index if it is not already open. The return value points
* at the SHA-1 within the mmapped index. Return NULL if there is an
* error.
*/
extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
/*
* Like nth_packed_object_sha1, but write the data into the object specified by
* the the first argument. Returns the first argument on success, and NULL on
* error.
*/
extern const struct object_id *nth_packed_object_oid(struct object_id *, struct packed_git *, uint32_t n);
/*
* Return the offset of the nth object within the specified packfile.
* The index must already be opened.
*/
extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
/*
* If the object named sha1 is present in the specified packfile,
* return its offset within the packfile; otherwise, return 0.
*/
extern off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
extern int is_pack_valid(struct packed_git *);
extern void *unpack_entry(struct repository *r, struct packed_git *, off_t, enum object_type *, unsigned long *);
extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
extern int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
extern void release_pack_memory(size_t);
/* global flag to enable extra checks when accessing packed objects */
extern int do_check_packed_object_crc;
extern int packed_object_info(struct repository *r,
struct packed_git *pack,
off_t offset, struct object_info *);
extern void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1);
extern const struct packed_git *has_packed_and_bad(struct repository *r, const unsigned char *sha1);
/*
* Iff a pack file in the given repository contains the object named by sha1,
* return true and store its location to e.
*/
extern int find_pack_entry(struct repository *r, const struct object_id *oid, struct pack_entry *e);
extern int has_object_pack(const struct object_id *oid);
extern int has_pack_index(const unsigned char *sha1);
/*
* Return 1 if an object in a promisor packfile is or refers to the given
* object, 0 otherwise.
*/
extern int is_promisor_object(const struct object_id *oid);
/*
* Expose a function for fuzz testing.
*
* load_idx() parses a block of memory as a packfile index and puts the results
* into a struct packed_git.
*
* This function should not be used directly. It is exposed here only so that we
* have a convenient entry-point for fuzz testing. For real uses, you should
* probably use open_pack_index() or parse_pack_index() instead.
*/
extern int load_idx(const char *path, const unsigned int hashsz, void *idx_map,
size_t idx_size, struct packed_git *p);
#endif