4ab15116c0125dcfb3c2dad54267cb986bd76c3c
[git/git.git] / packfile.h
1 #ifndef PACKFILE_H
2 #define PACKFILE_H
3
4 /*
5 * Generate the filename to be used for a pack file with checksum "sha1" and
6 * extension "ext". The result is written into the strbuf "buf", overwriting
7 * any existing contents. A pointer to buf->buf is returned as a convenience.
8 *
9 * Example: odb_pack_name(out, sha1, "idx") => ".git/objects/pack/pack-1234..idx"
10 */
11 extern char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, const char *ext);
12
13 /*
14 * Return the name of the (local) packfile with the specified sha1 in
15 * its name. The return value is a pointer to memory that is
16 * overwritten each time this function is called.
17 */
18 extern char *sha1_pack_name(const unsigned char *sha1);
19
20 /*
21 * Return the name of the (local) pack index file with the specified
22 * sha1 in its name. The return value is a pointer to memory that is
23 * overwritten each time this function is called.
24 */
25 extern char *sha1_pack_index_name(const unsigned char *sha1);
26
27 extern struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
28
29 /* A hook to report invalid files in pack directory */
30 #define PACKDIR_FILE_PACK 1
31 #define PACKDIR_FILE_IDX 2
32 #define PACKDIR_FILE_GARBAGE 4
33 extern void (*report_garbage)(unsigned seen_bits, const char *path);
34
35 extern void prepare_packed_git(void);
36 extern void reprepare_packed_git(void);
37 extern void install_packed_git(struct packed_git *pack);
38
39 /*
40 * Give a rough count of objects in the repository. This sacrifices accuracy
41 * for speed.
42 */
43 unsigned long approximate_object_count(void);
44
45 extern void pack_report(void);
46
47 /*
48 * mmap the index file for the specified packfile (if it is not
49 * already mmapped). Return 0 on success.
50 */
51 extern int open_pack_index(struct packed_git *);
52
53 /*
54 * munmap the index file for the specified packfile (if it is
55 * currently mmapped).
56 */
57 extern void close_pack_index(struct packed_git *);
58
59 extern unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
60 extern void close_pack_windows(struct packed_git *);
61 extern void close_all_packs(void);
62 extern void unuse_pack(struct pack_window **);
63 extern void clear_delta_base_cache(void);
64 extern struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
65
66 /*
67 * Make sure that a pointer access into an mmap'd index file is within bounds,
68 * and can provide at least 8 bytes of data.
69 *
70 * Note that this is only necessary for variable-length segments of the file
71 * (like the 64-bit extended offset table), as we compare the size to the
72 * fixed-length parts when we open the file.
73 */
74 extern void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
75
76 /*
77 * Return the SHA-1 of the nth object within the specified packfile.
78 * Open the index if it is not already open. The return value points
79 * at the SHA-1 within the mmapped index. Return NULL if there is an
80 * error.
81 */
82 extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
83 /*
84 * Like nth_packed_object_sha1, but write the data into the object specified by
85 * the the first argument. Returns the first argument on success, and NULL on
86 * error.
87 */
88 extern const struct object_id *nth_packed_object_oid(struct object_id *, struct packed_git *, uint32_t n);
89
90 /*
91 * Return the offset of the nth object within the specified packfile.
92 * The index must already be opened.
93 */
94 extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
95
96 /*
97 * If the object named sha1 is present in the specified packfile,
98 * return its offset within the packfile; otherwise, return 0.
99 */
100 extern off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
101
102 extern int is_pack_valid(struct packed_git *);
103 extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
104 extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
105 extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
106 extern int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
107
108 extern void release_pack_memory(size_t);
109
110 /* global flag to enable extra checks when accessing packed objects */
111 extern int do_check_packed_object_crc;
112
113 extern int packed_object_info(struct packed_git *pack, off_t offset, struct object_info *);
114
115 extern void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1);
116 extern const struct packed_git *has_packed_and_bad(const unsigned char *sha1);
117
118 #endif