packfile.h

   1 #ifndef PACKFILE_H
   2 #define PACKFILE_H
   3
   4 #include "object.h"
   5 #include "oidset.h"
   6
   7 /* in object-store.h */
   8 struct packed_git;
   9 struct object_info;
  10
  11 struct pack_window {
  12         struct pack_window *next;
  13         unsigned char *base;
  14         off_t offset;
  15         size_t len;
  16         unsigned int last_used;
  17         unsigned int inuse_cnt;
  18 };
  19
  20 struct pack_entry {
  21         off_t offset;
  22         struct packed_git *p;
  23 };
  24
  25 /*
  26  * Generate the filename to be used for a pack file with checksum "sha1" and
  27  * extension "ext". The result is written into the strbuf "buf", overwriting
  28  * any existing contents. A pointer to buf->buf is returned as a convenience.
  29  *
  30  * Example: odb_pack_name(out, sha1, "idx") => ".git/objects/pack/pack-1234..idx"
  31  */
  32 char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, const char *ext);
  33
  34 /*
  35  * Return the basename of the packfile, omitting any containing directory
  36  * (e.g., "pack-1234abcd[...].pack").
  37  */
  38 const char *pack_basename(struct packed_git *p);
  39
  40 /*
  41  * Parse the pack idx file found at idx_path and create a packed_git struct
  42  * which can be used with find_pack_entry_one().
  43  *
  44  * You probably don't want to use this function! It skips most of the normal
  45  * sanity checks (including whether we even have the matching .pack file),
  46  * and does not add the resulting packed_git struct to the internal list of
  47  * packs. You probably want add_packed_git() instead.
  48  */
  49 struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
  50
  51 typedef void each_file_in_pack_dir_fn(const char *full_path, size_t full_path_len,
  52                                       const char *file_name, void *data);
  53 void for_each_file_in_pack_subdir(const char *objdir,
  54                                   const char *subdir,
  55                                   each_file_in_pack_dir_fn fn,
  56                                   void *data);
  57 void for_each_file_in_pack_dir(const char *objdir,
  58                                each_file_in_pack_dir_fn fn,
  59                                void *data);
  60
  61 /* A hook to report invalid files in pack directory */
  62 #define PACKDIR_FILE_PACK 1
  63 #define PACKDIR_FILE_IDX 2
  64 #define PACKDIR_FILE_GARBAGE 4
  65 extern void (*report_garbage)(unsigned seen_bits, const char *path);
  66
  67 void reprepare_packed_git(struct repository *r);
  68 void install_packed_git(struct repository *r, struct packed_git *pack);
  69
  70 struct packed_git *get_packed_git(struct repository *r);
  71 struct list_head *get_packed_git_mru(struct repository *r);
  72 struct multi_pack_index *get_multi_pack_index(struct repository *r);
  73 struct multi_pack_index *get_local_multi_pack_index(struct repository *r);
  74 struct packed_git *get_all_packs(struct repository *r);
  75
  76 /*
  77  * Give a rough count of objects in the repository. This sacrifices accuracy
  78  * for speed.
  79  */
  80 unsigned long repo_approximate_object_count(struct repository *r);
  81
  82 /*
  83  * Find the pack within the "packs" list whose index contains the object "oid".
  84  * For general object lookups, you probably don't want this; use
  85  * find_pack_entry() instead.
  86  */
  87 struct packed_git *find_oid_pack(const struct object_id *oid,
  88                                  struct packed_git *packs);
  89
  90 void pack_report(void);
  91
  92 /*
  93  * mmap the index file for the specified packfile (if it is not
  94  * already mmapped).  Return 0 on success.
  95  */
  96 int open_pack_index(struct packed_git *);
  97
  98 /*
  99  * munmap the index file for the specified packfile (if it is
 100  * currently mmapped).
 101  */
 102 void close_pack_index(struct packed_git *);
 103
 104 int close_pack_fd(struct packed_git *p);
 105
 106 uint32_t get_pack_fanout(struct packed_git *p, uint32_t value);
 107
 108 struct raw_object_store;
 109
 110 unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
 111 void close_pack_windows(struct packed_git *);
 112 void close_pack(struct packed_git *);
 113 void close_object_store(struct raw_object_store *o);
 114 void unuse_pack(struct pack_window **);
 115 void clear_delta_base_cache(void);
 116 struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
 117
 118 /*
 119  * Unlink the .pack and associated extension files.
 120  * Does not unlink if 'force_delete' is false and the pack-file is
 121  * marked as ".keep".
 122  */
 123 void unlink_pack_path(const char *pack_name, int force_delete);
 124
 125 /*
 126  * Make sure that a pointer access into an mmap'd index file is within bounds,
 127  * and can provide at least 8 bytes of data.
 128  *
 129  * Note that this is only necessary for variable-length segments of the file
 130  * (like the 64-bit extended offset table), as we compare the size to the
 131  * fixed-length parts when we open the file.
 132  */
 133 void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
 134
 135 /*
 136  * Perform binary search on a pack-index for a given oid. Packfile is expected to
 137  * have a valid pack-index.
 138  *
 139  * See 'bsearch_hash' for more information.
 140  */
 141 int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result);
 142
 143 /*
 144  * Write the oid of the nth object within the specified packfile into the first
 145  * parameter. Open the index if it is not already open.  Returns 0 on success,
 146  * negative otherwise.
 147  */
 148 int nth_packed_object_id(struct object_id *, struct packed_git *, uint32_t n);
 149
 150 /*
 151  * Return the offset of the nth object within the specified packfile.
 152  * The index must already be opened.
 153  */
 154 off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
 155
 156 /*
 157  * If the object named by oid is present in the specified packfile,
 158  * return its offset within the packfile; otherwise, return 0.
 159  */
 160 off_t find_pack_entry_one(const struct object_id *oid, struct packed_git *);
 161
 162 int is_pack_valid(struct packed_git *);
 163 void *unpack_entry(struct repository *r, struct packed_git *, off_t, enum object_type *, unsigned long *);
 164 unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
 165 unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
 166 int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
 167 off_t get_delta_base(struct packed_git *p, struct pack_window **w_curs,
 168                      off_t *curpos, enum object_type type,
 169                      off_t delta_obj_offset);
 170
 171 void release_pack_memory(size_t);
 172
 173 /* global flag to enable extra checks when accessing packed objects */
 174 extern int do_check_packed_object_crc;
 175
 176 int packed_object_info(struct repository *r,
 177                        struct packed_git *pack,
 178                        off_t offset, struct object_info *);
 179
 180 void mark_bad_packed_object(struct packed_git *, const struct object_id *);
 181 const struct packed_git *has_packed_and_bad(struct repository *, const struct object_id *);
 182
 183 #define ON_DISK_KEEP_PACKS 1
 184 #define IN_CORE_KEEP_PACKS 2
 185
 186 /*
 187  * Iff a pack file in the given repository contains the object named by sha1,
 188  * return true and store its location to e.
 189  */
 190 int find_pack_entry(struct repository *r, const struct object_id *oid, struct pack_entry *e);
 191 int find_kept_pack_entry(struct repository *r, const struct object_id *oid, unsigned flags, struct pack_entry *e);
 192
 193 int has_object_pack(const struct object_id *oid);
 194 int has_object_kept_pack(const struct object_id *oid, unsigned flags);
 195
 196 /*
 197  * Return 1 if an object in a promisor packfile is or refers to the given
 198  * object, 0 otherwise.
 199  */
 200 int is_promisor_object(const struct object_id *oid);
 201
 202 /*
 203  * Expose a function for fuzz testing.
 204  *
 205  * load_idx() parses a block of memory as a packfile index and puts the results
 206  * into a struct packed_git.
 207  *
 208  * This function should not be used directly. It is exposed here only so that we
 209  * have a convenient entry-point for fuzz testing. For real uses, you should
 210  * probably use open_pack_index() instead.
 211  */
 212 int load_idx(const char *path, const unsigned int hashsz, void *idx_map,
 213              size_t idx_size, struct packed_git *p);
 214
 215 #endif