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 name of the (local) packfile with the specified sha1 in
  36  * its name.  The return value is a pointer to memory that is
  37  * overwritten each time this function is called.
  38  */
  39 char *sha1_pack_name(const unsigned char *sha1);
  40
  41 /*
  42  * Return the name of the (local) pack index file with the specified
  43  * sha1 in its name.  The return value is a pointer to memory that is
  44  * overwritten each time this function is called.
  45  */
  46 char *sha1_pack_index_name(const unsigned char *sha1);
  47
  48 /*
  49  * Return the basename of the packfile, omitting any containing directory
  50  * (e.g., "pack-1234abcd[...].pack").
  51  */
  52 const char *pack_basename(struct packed_git *p);
  53
  54 struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
  55
  56 typedef void each_file_in_pack_dir_fn(const char *full_path, size_t full_path_len,
  57                                       const char *file_name, void *data);
  58 void for_each_file_in_pack_dir(const char *objdir,
  59                                each_file_in_pack_dir_fn fn,
  60                                void *data);
  61
  62 /* A hook to report invalid files in pack directory */
  63 #define PACKDIR_FILE_PACK 1
  64 #define PACKDIR_FILE_IDX 2
  65 #define PACKDIR_FILE_GARBAGE 4
  66 extern void (*report_garbage)(unsigned seen_bits, const char *path);
  67
  68 void reprepare_packed_git(struct repository *r);
  69 void install_packed_git(struct repository *r, struct packed_git *pack);
  70
  71 struct packed_git *get_packed_git(struct repository *r);
  72 struct list_head *get_packed_git_mru(struct repository *r);
  73 struct multi_pack_index *get_multi_pack_index(struct repository *r);
  74 struct multi_pack_index *get_local_multi_pack_index(struct repository *r);
  75 struct packed_git *get_all_packs(struct repository *r);
  76
  77 /*
  78  * Give a rough count of objects in the repository. This sacrifices accuracy
  79  * for speed.
  80  */
  81 unsigned long repo_approximate_object_count(struct repository *r);
  82
  83 struct packed_git *find_sha1_pack(const unsigned char *sha1,
  84                                   struct packed_git *packs);
  85
  86 void pack_report(void);
  87
  88 /*
  89  * mmap the index file for the specified packfile (if it is not
  90  * already mmapped).  Return 0 on success.
  91  */
  92 int open_pack_index(struct packed_git *);
  93
  94 /*
  95  * munmap the index file for the specified packfile (if it is
  96  * currently mmapped).
  97  */
  98 void close_pack_index(struct packed_git *);
  99
 100 int close_pack_fd(struct packed_git *p);
 101
 102 uint32_t get_pack_fanout(struct packed_git *p, uint32_t value);
 103
 104 struct raw_object_store;
 105
 106 unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
 107 void close_pack_windows(struct packed_git *);
 108 void close_pack(struct packed_git *);
 109 void close_object_store(struct raw_object_store *o);
 110 void unuse_pack(struct pack_window **);
 111 void clear_delta_base_cache(void);
 112 struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
 113
 114 /*
 115  * Unlink the .pack and associated extension files.
 116  * Does not unlink if 'force_delete' is false and the pack-file is
 117  * marked as ".keep".
 118  */
 119 void unlink_pack_path(const char *pack_name, int force_delete);
 120
 121 /*
 122  * Make sure that a pointer access into an mmap'd index file is within bounds,
 123  * and can provide at least 8 bytes of data.
 124  *
 125  * Note that this is only necessary for variable-length segments of the file
 126  * (like the 64-bit extended offset table), as we compare the size to the
 127  * fixed-length parts when we open the file.
 128  */
 129 void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
 130
 131 /*
 132  * Perform binary search on a pack-index for a given oid. Packfile is expected to
 133  * have a valid pack-index.
 134  *
 135  * See 'bsearch_hash' for more information.
 136  */
 137 int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result);
 138
 139 /*
 140  * Write the oid of the nth object within the specified packfile into the first
 141  * parameter. Open the index if it is not already open.  Returns 0 on success,
 142  * negative otherwise.
 143  */
 144 int nth_packed_object_id(struct object_id *, struct packed_git *, uint32_t n);
 145
 146 /*
 147  * Return the offset of the nth object within the specified packfile.
 148  * The index must already be opened.
 149  */
 150 off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
 151
 152 /*
 153  * If the object named sha1 is present in the specified packfile,
 154  * return its offset within the packfile; otherwise, return 0.
 155  */
 156 off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
 157
 158 int is_pack_valid(struct packed_git *);
 159 void *unpack_entry(struct repository *r, struct packed_git *, off_t, enum object_type *, unsigned long *);
 160 unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
 161 unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
 162 int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
 163 off_t get_delta_base(struct packed_git *p, struct pack_window **w_curs,
 164                      off_t *curpos, enum object_type type,
 165                      off_t delta_obj_offset);
 166
 167 void release_pack_memory(size_t);
 168
 169 /* global flag to enable extra checks when accessing packed objects */
 170 extern int do_check_packed_object_crc;
 171
 172 int packed_object_info(struct repository *r,
 173                        struct packed_git *pack,
 174                        off_t offset, struct object_info *);
 175
 176 void mark_bad_packed_object(struct packed_git *, const struct object_id *);
 177 const struct packed_git *has_packed_and_bad(struct repository *, const struct object_id *);
 178
 179 #define ON_DISK_KEEP_PACKS 1
 180 #define IN_CORE_KEEP_PACKS 2
 181
 182 /*
 183  * Iff a pack file in the given repository contains the object named by sha1,
 184  * return true and store its location to e.
 185  */
 186 int find_pack_entry(struct repository *r, const struct object_id *oid, struct pack_entry *e);
 187 int find_kept_pack_entry(struct repository *r, const struct object_id *oid, unsigned flags, struct pack_entry *e);
 188
 189 int has_object_pack(const struct object_id *oid);
 190 int has_object_kept_pack(const struct object_id *oid, unsigned flags);
 191
 192 int has_pack_index(const unsigned char *sha1);
 193
 194 /*
 195  * Return 1 if an object in a promisor packfile is or refers to the given
 196  * object, 0 otherwise.
 197  */
 198 int is_promisor_object(const struct object_id *oid);
 199
 200 /*
 201  * Expose a function for fuzz testing.
 202  *
 203  * load_idx() parses a block of memory as a packfile index and puts the results
 204  * into a struct packed_git.
 205  *
 206  * This function should not be used directly. It is exposed here only so that we
 207  * have a convenient entry-point for fuzz testing. For real uses, you should
 208  * probably use open_pack_index() or parse_pack_index() instead.
 209  */
 210 int load_idx(const char *path, const unsigned int hashsz, void *idx_map,
 211              size_t idx_size, struct packed_git *p);
 212
 213 #endif