git/object-store.h

380 строки
12 KiB
C

#ifndef OBJECT_STORE_H
#define OBJECT_STORE_H
#include "cache.h"
#include "oidmap.h"
#include "list.h"
#include "sha1-array.h"
#include "strbuf.h"
struct object_directory {
struct object_directory *next;
/*
* Used to store the results of readdir(3) calls when we are OK
* sacrificing accuracy due to races for speed. That includes
* object existence with OBJECT_INFO_QUICK, as well as
* our search for unique abbreviated hashes. Don't use it for tasks
* requiring greater accuracy!
*
* Be sure to call odb_load_loose_cache() before using.
*/
char loose_objects_subdir_seen[256];
struct oid_array loose_objects_cache[256];
/*
* Path to the alternative object store. If this is a relative path,
* it is relative to the current working directory.
*/
char *path;
};
void prepare_alt_odb(struct repository *r);
char *compute_alternate_path(const char *path, struct strbuf *err);
typedef int alt_odb_fn(struct object_directory *, void *);
int foreach_alt_odb(alt_odb_fn, void*);
/*
* Add the directory to the on-disk alternates file; the new entry will also
* take effect in the current process.
*/
void add_to_alternates_file(const char *dir);
/*
* Add the directory to the in-memory list of alternates (along with any
* recursive alternates it points to), but do not modify the on-disk alternates
* file.
*/
void add_to_alternates_memory(const char *dir);
/*
* Populate and return the loose object cache array corresponding to the
* given object ID.
*/
struct oid_array *odb_loose_cache(struct object_directory *odb,
const struct object_id *oid);
/* Empty the loose object cache for the specified object directory. */
void odb_clear_loose_cache(struct object_directory *odb);
struct packed_git {
struct packed_git *next;
struct list_head mru;
struct pack_window *windows;
off_t pack_size;
const void *index_data;
size_t index_size;
uint32_t num_objects;
uint32_t num_bad_objects;
unsigned char *bad_object_sha1;
int index_version;
time_t mtime;
int pack_fd;
int index; /* for builtin/pack-objects.c */
unsigned pack_local:1,
pack_keep:1,
pack_keep_in_core:1,
freshened:1,
do_not_close:1,
pack_promisor:1,
multi_pack_index:1;
unsigned char hash[GIT_MAX_RAWSZ];
struct revindex_entry *revindex;
/* something like ".git/objects/pack/xxxxx.pack" */
char pack_name[FLEX_ARRAY]; /* more */
};
struct multi_pack_index;
struct raw_object_store {
/*
* Set of all object directories; the main directory is first (and
* cannot be NULL after initialization). Subsequent directories are
* alternates.
*/
struct object_directory *odb;
struct object_directory **odb_tail;
int loaded_alternates;
/*
* A list of alternate object directories loaded from the environment;
* this should not generally need to be accessed directly, but will
* populate the "odb" list when prepare_alt_odb() is run.
*/
char *alternate_db;
/*
* Objects that should be substituted by other objects
* (see git-replace(1)).
*/
struct oidmap *replace_map;
struct commit_graph *commit_graph;
unsigned commit_graph_attempted : 1; /* if loading has been attempted */
/*
* private data
*
* should only be accessed directly by packfile.c and midx.c
*/
struct multi_pack_index *multi_pack_index;
/*
* private data
*
* should only be accessed directly by packfile.c
*/
struct packed_git *packed_git;
/* A most-recently-used ordered version of the packed_git list. */
struct list_head packed_git_mru;
/*
* A fast, rough count of the number of objects in the repository.
* These two fields are not meant for direct access. Use
* approximate_object_count() instead.
*/
unsigned long approximate_object_count;
unsigned approximate_object_count_valid : 1;
/*
* Whether packed_git has already been populated with this repository's
* packs.
*/
unsigned packed_git_initialized : 1;
};
struct raw_object_store *raw_object_store_new(void);
void raw_object_store_clear(struct raw_object_store *o);
/*
* Put in `buf` the name of the file in the local object database that
* would be used to store a loose object with the specified oid.
*/
const char *loose_object_path(struct repository *r, struct strbuf *buf,
const struct object_id *oid);
void *map_loose_object(struct repository *r, const struct object_id *oid,
unsigned long *size);
void *read_object_file_extended(struct repository *r,
const struct object_id *oid,
enum object_type *type,
unsigned long *size, int lookup_replace);
static inline void *repo_read_object_file(struct repository *r,
const struct object_id *oid,
enum object_type *type,
unsigned long *size)
{
return read_object_file_extended(r, oid, type, size, 1);
}
#ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
#define read_object_file(oid, type, size) repo_read_object_file(the_repository, oid, type, size)
#endif
/* Read and unpack an object file into memory, write memory to an object file */
int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
int hash_object_file(const void *buf, unsigned long len,
const char *type, struct object_id *oid);
int write_object_file(const void *buf, unsigned long len,
const char *type, struct object_id *oid);
int hash_object_file_literally(const void *buf, unsigned long len,
const char *type, struct object_id *oid,
unsigned flags);
int pretend_object_file(void *, unsigned long, enum object_type,
struct object_id *oid);
int force_object_loose(const struct object_id *oid, time_t mtime);
/*
* Open the loose object at path, check its hash, and return the contents,
* type, and size. If the object is a blob, then "contents" may return NULL,
* to allow streaming of large blobs.
*
* Returns 0 on success, negative on error (details may be written to stderr).
*/
int read_loose_object(const char *path,
const struct object_id *expected_oid,
enum object_type *type,
unsigned long *size,
void **contents);
#ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
#define has_sha1_file_with_flags(sha1, flags) repo_has_sha1_file_with_flags(the_repository, sha1, flags)
#define has_sha1_file(sha1) repo_has_sha1_file(the_repository, sha1)
#endif
/* Same as the above, except for struct object_id. */
int repo_has_object_file(struct repository *r, const struct object_id *oid);
int repo_has_object_file_with_flags(struct repository *r,
const struct object_id *oid, int flags);
#ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
#define has_object_file(oid) repo_has_object_file(the_repository, oid)
#define has_object_file_with_flags(oid, flags) repo_has_object_file_with_flags(the_repository, oid, flags)
#endif
/*
* Return true iff an alternate object database has a loose object
* with the specified name. This function does not respect replace
* references.
*/
int has_loose_object_nonlocal(const struct object_id *);
void assert_oid_type(const struct object_id *oid, enum object_type expect);
struct object_info {
/* Request */
enum object_type *typep;
unsigned long *sizep;
off_t *disk_sizep;
unsigned char *delta_base_sha1;
struct strbuf *type_name;
void **contentp;
/* Response */
enum {
OI_CACHED,
OI_LOOSE,
OI_PACKED,
OI_DBCACHED
} whence;
union {
/*
* struct {
* ... Nothing to expose in this case
* } cached;
* struct {
* ... Nothing to expose in this case
* } loose;
*/
struct {
struct packed_git *pack;
off_t offset;
unsigned int is_delta;
} packed;
} u;
};
/*
* Initializer for a "struct object_info" that wants no items. You may
* also memset() the memory to all-zeroes.
*/
#define OBJECT_INFO_INIT {NULL}
/* Invoke lookup_replace_object() on the given hash */
#define OBJECT_INFO_LOOKUP_REPLACE 1
/* Allow reading from a loose object file of unknown/bogus type */
#define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2
/* Do not check cached storage */
#define OBJECT_INFO_SKIP_CACHED 4
/* Do not retry packed storage after checking packed and loose storage */
#define OBJECT_INFO_QUICK 8
/* Do not check loose object */
#define OBJECT_INFO_IGNORE_LOOSE 16
/*
* Do not attempt to fetch the object if missing (even if fetch_is_missing is
* nonzero). This is meant for bulk prefetching of missing blobs in a partial
* clone. Implies OBJECT_INFO_QUICK.
*/
#define OBJECT_INFO_FOR_PREFETCH (32 + OBJECT_INFO_QUICK)
int oid_object_info_extended(struct repository *r,
const struct object_id *,
struct object_info *, unsigned flags);
/*
* Iterate over the files in the loose-object parts of the object
* directory "path", triggering the following callbacks:
*
* - loose_object is called for each loose object we find.
*
* - loose_cruft is called for any files that do not appear to be
* loose objects. Note that we only look in the loose object
* directories "objects/[0-9a-f]{2}/", so we will not report
* "objects/foobar" as cruft.
*
* - loose_subdir is called for each top-level hashed subdirectory
* of the object directory (e.g., "$OBJDIR/f0"). It is called
* after the objects in the directory are processed.
*
* Any callback that is NULL will be ignored. Callbacks returning non-zero
* will end the iteration.
*
* In the "buf" variant, "path" is a strbuf which will also be used as a
* scratch buffer, but restored to its original contents before
* the function returns.
*/
typedef int each_loose_object_fn(const struct object_id *oid,
const char *path,
void *data);
typedef int each_loose_cruft_fn(const char *basename,
const char *path,
void *data);
typedef int each_loose_subdir_fn(unsigned int nr,
const char *path,
void *data);
int for_each_file_in_obj_subdir(unsigned int subdir_nr,
struct strbuf *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data);
int for_each_loose_file_in_objdir(const char *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data);
int for_each_loose_file_in_objdir_buf(struct strbuf *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data);
/* Flags for for_each_*_object() below. */
enum for_each_object_flags {
/* Iterate only over local objects, not alternates. */
FOR_EACH_OBJECT_LOCAL_ONLY = (1<<0),
/* Only iterate over packs obtained from the promisor remote. */
FOR_EACH_OBJECT_PROMISOR_ONLY = (1<<1),
/*
* Visit objects within a pack in packfile order rather than .idx order
*/
FOR_EACH_OBJECT_PACK_ORDER = (1<<2),
};
/*
* Iterate over all accessible loose objects without respect to
* reachability. By default, this includes both local and alternate objects.
* The order in which objects are visited is unspecified.
*
* Any flags specific to packs are ignored.
*/
int for_each_loose_object(each_loose_object_fn, void *,
enum for_each_object_flags flags);
/*
* Iterate over all accessible packed objects without respect to reachability.
* By default, this includes both local and alternate packs.
*
* Note that some objects may appear twice if they are found in multiple packs.
* Each pack is visited in an unspecified order. By default, objects within a
* pack are visited in pack-idx order (i.e., sorted by oid).
*/
typedef int each_packed_object_fn(const struct object_id *oid,
struct packed_git *pack,
uint32_t pos,
void *data);
int for_each_object_in_pack(struct packed_git *p,
each_packed_object_fn, void *data,
enum for_each_object_flags flags);
int for_each_packed_object(each_packed_object_fn, void *,
enum for_each_object_flags flags);
#endif /* OBJECT_STORE_H */