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 struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path);
  35
  36 typedef void each_file_in_pack_dir_fn(const char *full_path, size_t full_path_len,
  37                                       const char *file_pach, void *data);
  38 void for_each_file_in_pack_dir(const char *objdir,
  39                                each_file_in_pack_dir_fn fn,
  40                                void *data);
  41
  42 /* A hook to report invalid files in pack directory */
  43 #define PACKDIR_FILE_PACK 1
  44 #define PACKDIR_FILE_IDX 2
  45 #define PACKDIR_FILE_GARBAGE 4
  46 extern void (*report_garbage)(unsigned seen_bits, const char *path);
  47
  48 void reprepare_packed_git(struct repository *r);
  49 void install_packed_git(struct repository *r, struct packed_git *pack);
  50
  51 struct packed_git *get_packed_git(struct repository *r);
  52 struct list_head *get_packed_git_mru(struct repository *r);
  53 struct multi_pack_index *get_multi_pack_index(struct repository *r);
  54 struct packed_git *get_all_packs(struct repository *r);
  55
  56 /*
  57  * Give a rough count of objects in the repository. This sacrifices accuracy
  58  * for speed.
  59  */
  60 unsigned long approximate_object_count(void);
  61
  62 struct packed_git *find_sha1_pack(const unsigned char *sha1,
  63                                   struct packed_git *packs);
  64
  65 void pack_report(void);
  66
  67 /*
  68  * mmap the index file for the specified packfile (if it is not
  69  * already mmapped).  Return 0 on success.
  70  */
  71 int open_pack_index(struct packed_git *);
  72
  73 /*
  74  * munmap the index file for the specified packfile (if it is
  75  * currently mmapped).
  76  */
  77 void close_pack_index(struct packed_git *);
  78
  79 int close_pack_fd(struct packed_git *p);
  80
  81 uint32_t get_pack_fanout(struct packed_git *p, uint32_t value);
  82
  83 unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
  84 void close_pack_windows(struct packed_git *);
  85 void close_pack(struct packed_git *);
  86 void close_all_packs(struct raw_object_store *o);
  87 void unuse_pack(struct pack_window **);
  88 void clear_delta_base_cache(void);
  89 struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
  90
  91 /*
  92  * Make sure that a pointer access into an mmap'd index file is within bounds,
  93  * and can provide at least 8 bytes of data.
  94  *
  95  * Note that this is only necessary for variable-length segments of the file
  96  * (like the 64-bit extended offset table), as we compare the size to the
  97  * fixed-length parts when we open the file.
  98  */
  99 void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
 100
 101 /*
 102  * Perform binary search on a pack-index for a given oid. Packfile is expected to
 103  * have a valid pack-index.
 104  *
 105  * See 'bsearch_hash' for more information.
 106  */
 107 int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result);
 108
 109 /*
 110  * Return the SHA-1 of the nth object within the specified packfile.
 111  * Open the index if it is not already open.  The return value points
 112  * at the SHA-1 within the mmapped index.  Return NULL if there is an
 113  * error.
 114  */
 115 const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
 116 /*
 117  * Like nth_packed_object_sha1, but write the data into the object specified by
 118  * the the first argument.  Returns the first argument on success, and NULL on
 119  * error.
 120  */
 121 const struct object_id *nth_packed_object_oid(struct object_id *, struct packed_git *, uint32_t n);
 122
 123 /*
 124  * Return the offset of the nth object within the specified packfile.
 125  * The index must already be opened.
 126  */
 127 off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
 128
 129 /*
 130  * If the object named sha1 is present in the specified packfile,
 131  * return its offset within the packfile; otherwise, return 0.
 132  */
 133 off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
 134
 135 int is_pack_valid(struct packed_git *);
 136 void *unpack_entry(struct repository *r, struct packed_git *, off_t, enum object_type *, unsigned long *);
 137 unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
 138 unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
 139 int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
 140
 141 void release_pack_memory(size_t);
 142
 143 /* global flag to enable extra checks when accessing packed objects */
 144 extern int do_check_packed_object_crc;
 145
 146 int packed_object_info(struct repository *r,
 147                        struct packed_git *pack,
 148                        off_t offset, struct object_info *);
 149
 150 void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1);
 151 const struct packed_git *has_packed_and_bad(struct repository *r, const unsigned char *sha1);
 152
 153 /*
 154  * Iff a pack file in the given repository contains the object named by sha1,
 155  * return true and store its location to e.
 156  */
 157 int find_pack_entry(struct repository *r, const struct object_id *oid, struct pack_entry *e);
 158
 159 int has_object_pack(const struct object_id *oid);
 160
 161 int has_pack_index(const unsigned char *sha1);
 162
 163 /*
 164  * Return 1 if an object in a promisor packfile is or refers to the given
 165  * object, 0 otherwise.
 166  */
 167 int is_promisor_object(const struct object_id *oid);
 168
 169 /*
 170  * Expose a function for fuzz testing.
 171  *
 172  * load_idx() parses a block of memory as a packfile index and puts the results
 173  * into a struct packed_git.
 174  *
 175  * This function should not be used directly. It is exposed here only so that we
 176  * have a convenient entry-point for fuzz testing. For real uses, you should
 177  * probably use open_pack_index() or parse_pack_index() instead.
 178  */
 179 int load_idx(const char *path, const unsigned int hashsz, void *idx_map,
 180              size_t idx_size, struct packed_git *p);
 181
 182 #endif