packfile.h

   1 #ifndef PACKFILE_H
   2 #define PACKFILE_H
   3
   4 #include "cache.h"
   5 #include "oidset.h"
   6
   7 /* in object-store.h */
   8 struct packed_git;
   9 struct object_info;
  10
  11 /*
  12  * Generate the filename to be used for a pack file with checksum "sha1" and
  13  * extension "ext". The result is written into the strbuf "buf", overwriting
  14  * any existing contents. A pointer to buf->buf is returned as a convenience.
  15  *
  16  * Example: odb_pack_name(out, sha1, "idx") => ".git/objects/pack/pack-1234..idx"
  17  */
  18 char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, const char *ext);
  19
  20 /*
  21  * Return the name of the (local) packfile with the specified sha1 in
  22  * its name.  The return value is a pointer to memory that is
  23  * overwritten each time this function is called.
  24  */
  25 char *sha1_pack_name(const unsigned char *sha1);
  26
  27 /*
  28  * Return the name of the (local) pack index file with the specified
  29  * sha1 in its name.  The return value is a pointer to memory that is
  30  * overwritten each time this function is called.
  31  */
  32 char *sha1_pack_index_name(const unsigned char *sha1);
  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 struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
  41
  42 typedef void each_file_in_pack_dir_fn(const char *full_path, size_t full_path_len,
  43                                       const char *file_pach, void *data);
  44 void for_each_file_in_pack_dir(const char *objdir,
  45                                each_file_in_pack_dir_fn fn,
  46                                void *data);
  47
  48 /* A hook to report invalid files in pack directory */
  49 #define PACKDIR_FILE_PACK 1
  50 #define PACKDIR_FILE_IDX 2
  51 #define PACKDIR_FILE_GARBAGE 4
  52 extern void (*report_garbage)(unsigned seen_bits, const char *path);
  53
  54 void reprepare_packed_git(struct repository *r);
  55 void install_packed_git(struct repository *r, struct packed_git *pack);
  56
  57 struct packed_git *get_packed_git(struct repository *r);
  58 struct list_head *get_packed_git_mru(struct repository *r);
  59 struct multi_pack_index *get_multi_pack_index(struct repository *r);
  60 struct packed_git *get_all_packs(struct repository *r);
  61
  62 /*
  63  * Give a rough count of objects in the repository. This sacrifices accuracy
  64  * for speed.
  65  */
  66 unsigned long approximate_object_count(void);
  67
  68 struct packed_git *find_sha1_pack(const unsigned char *sha1,
  69                                   struct packed_git *packs);
  70
  71 void pack_report(void);
  72
  73 /*
  74  * mmap the index file for the specified packfile (if it is not
  75  * already mmapped).  Return 0 on success.
  76  */
  77 int open_pack_index(struct packed_git *);
  78
  79 /*
  80  * munmap the index file for the specified packfile (if it is
  81  * currently mmapped).
  82  */
  83 void close_pack_index(struct packed_git *);
  84
  85 int close_pack_fd(struct packed_git *p);
  86
  87 uint32_t get_pack_fanout(struct packed_git *p, uint32_t value);
  88
  89 unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
  90 void close_pack_windows(struct packed_git *);
  91 void close_pack(struct packed_git *);
  92 void close_all_packs(struct raw_object_store *o);
  93 void unuse_pack(struct pack_window **);
  94 void clear_delta_base_cache(void);
  95 struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
  96
  97 /*
  98  * Make sure that a pointer access into an mmap'd index file is within bounds,
  99  * and can provide at least 8 bytes of data.
 100  *
 101  * Note that this is only necessary for variable-length segments of the file
 102  * (like the 64-bit extended offset table), as we compare the size to the
 103  * fixed-length parts when we open the file.
 104  */
 105 void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
 106
 107 /*
 108  * Perform binary search on a pack-index for a given oid. Packfile is expected to
 109  * have a valid pack-index.
 110  *
 111  * See 'bsearch_hash' for more information.
 112  */
 113 int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result);
 114
 115 /*
 116  * Return the SHA-1 of the nth object within the specified packfile.
 117  * Open the index if it is not already open.  The return value points
 118  * at the SHA-1 within the mmapped index.  Return NULL if there is an
 119  * error.
 120  */
 121 const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
 122 /*
 123  * Like nth_packed_object_sha1, but write the data into the object specified by
 124  * the the first argument.  Returns the first argument on success, and NULL on
 125  * error.
 126  */
 127 const struct object_id *nth_packed_object_oid(struct object_id *, struct packed_git *, uint32_t n);
 128
 129 /*
 130  * Return the offset of the nth object within the specified packfile.
 131  * The index must already be opened.
 132  */
 133 off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
 134
 135 /*
 136  * If the object named sha1 is present in the specified packfile,
 137  * return its offset within the packfile; otherwise, return 0.
 138  */
 139 off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
 140
 141 int is_pack_valid(struct packed_git *);
 142 void *unpack_entry(struct repository *r, struct packed_git *, off_t, enum object_type *, unsigned long *);
 143 unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
 144 unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
 145 int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
 146
 147 void release_pack_memory(size_t);
 148
 149 /* global flag to enable extra checks when accessing packed objects */
 150 extern int do_check_packed_object_crc;
 151
 152 int packed_object_info(struct repository *r,
 153                        struct packed_git *pack,
 154                        off_t offset, struct object_info *);
 155
 156 void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1);
 157 const struct packed_git *has_packed_and_bad(struct repository *r, const unsigned char *sha1);
 158
 159 /*
 160  * Iff a pack file in the given repository contains the object named by sha1,
 161  * return true and store its location to e.
 162  */
 163 int find_pack_entry(struct repository *r, const struct object_id *oid, struct pack_entry *e);
 164
 165 int has_object_pack(const struct object_id *oid);
 166
 167 int has_pack_index(const unsigned char *sha1);
 168
 169 /*
 170  * Return 1 if an object in a promisor packfile is or refers to the given
 171  * object, 0 otherwise.
 172  */
 173 int is_promisor_object(const struct object_id *oid);
 174
 175 /*
 176  * Expose a function for fuzz testing.
 177  *
 178  * load_idx() parses a block of memory as a packfile index and puts the results
 179  * into a struct packed_git.
 180  *
 181  * This function should not be used directly. It is exposed here only so that we
 182  * have a convenient entry-point for fuzz testing. For real uses, you should
 183  * probably use open_pack_index() or parse_pack_index() instead.
 184  */
 185 int load_idx(const char *path, const unsigned int hashsz, void *idx_map,
 186              size_t idx_size, struct packed_git *p);
 187
 188 #endif