7236c571c0c036ceab15b1579841dd4eab09e761
   1#ifndef OBJECT_STORE_H
   2#define OBJECT_STORE_H
   3
   4#include "cache.h"
   5#include "oidmap.h"
   6#include "list.h"
   7#include "sha1-array.h"
   8#include "strbuf.h"
   9
  10struct object_directory {
  11        struct object_directory *next;
  12
  13        /*
  14         * Used to store the results of readdir(3) calls when we are OK
  15         * sacrificing accuracy due to races for speed. That includes
  16         * object existence with OBJECT_INFO_QUICK, as well as
  17         * our search for unique abbreviated hashes. Don't use it for tasks
  18         * requiring greater accuracy!
  19         *
  20         * Be sure to call odb_load_loose_cache() before using.
  21         */
  22        char loose_objects_subdir_seen[256];
  23        struct oid_array loose_objects_cache;
  24
  25        /*
  26         * Path to the alternative object store. If this is a relative path,
  27         * it is relative to the current working directory.
  28         */
  29        char *path;
  30};
  31
  32void prepare_alt_odb(struct repository *r);
  33char *compute_alternate_path(const char *path, struct strbuf *err);
  34typedef int alt_odb_fn(struct object_directory *, void *);
  35int foreach_alt_odb(alt_odb_fn, void*);
  36
  37/*
  38 * Add the directory to the on-disk alternates file; the new entry will also
  39 * take effect in the current process.
  40 */
  41void add_to_alternates_file(const char *dir);
  42
  43/*
  44 * Add the directory to the in-memory list of alternates (along with any
  45 * recursive alternates it points to), but do not modify the on-disk alternates
  46 * file.
  47 */
  48void add_to_alternates_memory(const char *dir);
  49
  50/*
  51 * Populate an odb's loose object cache for one particular subdirectory (i.e.,
  52 * the one that corresponds to the first byte of objects you're interested in,
  53 * from 0 to 255 inclusive).
  54 */
  55void odb_load_loose_cache(struct object_directory *odb, int subdir_nr);
  56
  57/*
  58 * Populate and return the loose object cache array corresponding to the
  59 * given object ID.
  60 */
  61struct oid_array *odb_loose_cache(struct object_directory *odb,
  62                                  const struct object_id *oid);
  63
  64struct packed_git {
  65        struct packed_git *next;
  66        struct list_head mru;
  67        struct pack_window *windows;
  68        off_t pack_size;
  69        const void *index_data;
  70        size_t index_size;
  71        uint32_t num_objects;
  72        uint32_t num_bad_objects;
  73        unsigned char *bad_object_sha1;
  74        int index_version;
  75        time_t mtime;
  76        int pack_fd;
  77        int index;              /* for builtin/pack-objects.c */
  78        unsigned pack_local:1,
  79                 pack_keep:1,
  80                 pack_keep_in_core:1,
  81                 freshened:1,
  82                 do_not_close:1,
  83                 pack_promisor:1;
  84        unsigned char sha1[20];
  85        struct revindex_entry *revindex;
  86        /* something like ".git/objects/pack/xxxxx.pack" */
  87        char pack_name[FLEX_ARRAY]; /* more */
  88};
  89
  90struct multi_pack_index;
  91
  92struct raw_object_store {
  93        /*
  94         * Set of all object directories; the main directory is first (and
  95         * cannot be NULL after initialization). Subsequent directories are
  96         * alternates.
  97         */
  98        struct object_directory *odb;
  99        struct object_directory **odb_tail;
 100        int loaded_alternates;
 101
 102        /*
 103         * A list of alternate object directories loaded from the environment;
 104         * this should not generally need to be accessed directly, but will
 105         * populate the "odb" list when prepare_alt_odb() is run.
 106         */
 107        char *alternate_db;
 108
 109        /*
 110         * Objects that should be substituted by other objects
 111         * (see git-replace(1)).
 112         */
 113        struct oidmap *replace_map;
 114
 115        struct commit_graph *commit_graph;
 116        unsigned commit_graph_attempted : 1; /* if loading has been attempted */
 117
 118        /*
 119         * private data
 120         *
 121         * should only be accessed directly by packfile.c and midx.c
 122         */
 123        struct multi_pack_index *multi_pack_index;
 124
 125        /*
 126         * private data
 127         *
 128         * should only be accessed directly by packfile.c
 129         */
 130
 131        struct packed_git *packed_git;
 132        /* A most-recently-used ordered version of the packed_git list. */
 133        struct list_head packed_git_mru;
 134
 135        /*
 136         * A linked list containing all packfiles, starting with those
 137         * contained in the multi_pack_index.
 138         */
 139        struct packed_git *all_packs;
 140
 141        /*
 142         * A fast, rough count of the number of objects in the repository.
 143         * These two fields are not meant for direct access. Use
 144         * approximate_object_count() instead.
 145         */
 146        unsigned long approximate_object_count;
 147        unsigned approximate_object_count_valid : 1;
 148
 149        /*
 150         * Whether packed_git has already been populated with this repository's
 151         * packs.
 152         */
 153        unsigned packed_git_initialized : 1;
 154};
 155
 156struct raw_object_store *raw_object_store_new(void);
 157void raw_object_store_clear(struct raw_object_store *o);
 158
 159/*
 160 * Put in `buf` the name of the file in the local object database that
 161 * would be used to store a loose object with the specified sha1.
 162 */
 163const char *loose_object_path(struct repository *r, struct strbuf *buf, const unsigned char *sha1);
 164
 165void *map_sha1_file(struct repository *r, const unsigned char *sha1, unsigned long *size);
 166
 167extern void *read_object_file_extended(const struct object_id *oid,
 168                                       enum object_type *type,
 169                                       unsigned long *size, int lookup_replace);
 170static inline void *read_object_file(const struct object_id *oid, enum object_type *type, unsigned long *size)
 171{
 172        return read_object_file_extended(oid, type, size, 1);
 173}
 174
 175/* Read and unpack an object file into memory, write memory to an object file */
 176int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
 177
 178extern int hash_object_file(const void *buf, unsigned long len,
 179                            const char *type, struct object_id *oid);
 180
 181extern int write_object_file(const void *buf, unsigned long len,
 182                             const char *type, struct object_id *oid);
 183
 184extern int hash_object_file_literally(const void *buf, unsigned long len,
 185                                      const char *type, struct object_id *oid,
 186                                      unsigned flags);
 187
 188extern int pretend_object_file(void *, unsigned long, enum object_type,
 189                               struct object_id *oid);
 190
 191extern int force_object_loose(const struct object_id *oid, time_t mtime);
 192
 193/*
 194 * Open the loose object at path, check its hash, and return the contents,
 195 * type, and size. If the object is a blob, then "contents" may return NULL,
 196 * to allow streaming of large blobs.
 197 *
 198 * Returns 0 on success, negative on error (details may be written to stderr).
 199 */
 200int read_loose_object(const char *path,
 201                      const struct object_id *expected_oid,
 202                      enum object_type *type,
 203                      unsigned long *size,
 204                      void **contents);
 205
 206/*
 207 * Convenience for sha1_object_info_extended() with a NULL struct
 208 * object_info. OBJECT_INFO_SKIP_CACHED is automatically set; pass
 209 * nonzero flags to also set other flags.
 210 */
 211extern int has_sha1_file_with_flags(const unsigned char *sha1, int flags);
 212static inline int has_sha1_file(const unsigned char *sha1)
 213{
 214        return has_sha1_file_with_flags(sha1, 0);
 215}
 216
 217/* Same as the above, except for struct object_id. */
 218extern int has_object_file(const struct object_id *oid);
 219extern int has_object_file_with_flags(const struct object_id *oid, int flags);
 220
 221/*
 222 * Return true iff an alternate object database has a loose object
 223 * with the specified name.  This function does not respect replace
 224 * references.
 225 */
 226extern int has_loose_object_nonlocal(const struct object_id *);
 227
 228extern void assert_oid_type(const struct object_id *oid, enum object_type expect);
 229
 230struct object_info {
 231        /* Request */
 232        enum object_type *typep;
 233        unsigned long *sizep;
 234        off_t *disk_sizep;
 235        unsigned char *delta_base_sha1;
 236        struct strbuf *type_name;
 237        void **contentp;
 238
 239        /* Response */
 240        enum {
 241                OI_CACHED,
 242                OI_LOOSE,
 243                OI_PACKED,
 244                OI_DBCACHED
 245        } whence;
 246        union {
 247                /*
 248                 * struct {
 249                 *      ... Nothing to expose in this case
 250                 * } cached;
 251                 * struct {
 252                 *      ... Nothing to expose in this case
 253                 * } loose;
 254                 */
 255                struct {
 256                        struct packed_git *pack;
 257                        off_t offset;
 258                        unsigned int is_delta;
 259                } packed;
 260        } u;
 261};
 262
 263/*
 264 * Initializer for a "struct object_info" that wants no items. You may
 265 * also memset() the memory to all-zeroes.
 266 */
 267#define OBJECT_INFO_INIT {NULL}
 268
 269/* Invoke lookup_replace_object() on the given hash */
 270#define OBJECT_INFO_LOOKUP_REPLACE 1
 271/* Allow reading from a loose object file of unknown/bogus type */
 272#define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2
 273/* Do not check cached storage */
 274#define OBJECT_INFO_SKIP_CACHED 4
 275/* Do not retry packed storage after checking packed and loose storage */
 276#define OBJECT_INFO_QUICK 8
 277/* Do not check loose object */
 278#define OBJECT_INFO_IGNORE_LOOSE 16
 279
 280int oid_object_info_extended(struct repository *r,
 281                             const struct object_id *,
 282                             struct object_info *, unsigned flags);
 283
 284/*
 285 * Iterate over the files in the loose-object parts of the object
 286 * directory "path", triggering the following callbacks:
 287 *
 288 *  - loose_object is called for each loose object we find.
 289 *
 290 *  - loose_cruft is called for any files that do not appear to be
 291 *    loose objects. Note that we only look in the loose object
 292 *    directories "objects/[0-9a-f]{2}/", so we will not report
 293 *    "objects/foobar" as cruft.
 294 *
 295 *  - loose_subdir is called for each top-level hashed subdirectory
 296 *    of the object directory (e.g., "$OBJDIR/f0"). It is called
 297 *    after the objects in the directory are processed.
 298 *
 299 * Any callback that is NULL will be ignored. Callbacks returning non-zero
 300 * will end the iteration.
 301 *
 302 * In the "buf" variant, "path" is a strbuf which will also be used as a
 303 * scratch buffer, but restored to its original contents before
 304 * the function returns.
 305 */
 306typedef int each_loose_object_fn(const struct object_id *oid,
 307                                 const char *path,
 308                                 void *data);
 309typedef int each_loose_cruft_fn(const char *basename,
 310                                const char *path,
 311                                void *data);
 312typedef int each_loose_subdir_fn(unsigned int nr,
 313                                 const char *path,
 314                                 void *data);
 315int for_each_file_in_obj_subdir(unsigned int subdir_nr,
 316                                struct strbuf *path,
 317                                each_loose_object_fn obj_cb,
 318                                each_loose_cruft_fn cruft_cb,
 319                                each_loose_subdir_fn subdir_cb,
 320                                void *data);
 321int for_each_loose_file_in_objdir(const char *path,
 322                                  each_loose_object_fn obj_cb,
 323                                  each_loose_cruft_fn cruft_cb,
 324                                  each_loose_subdir_fn subdir_cb,
 325                                  void *data);
 326int for_each_loose_file_in_objdir_buf(struct strbuf *path,
 327                                      each_loose_object_fn obj_cb,
 328                                      each_loose_cruft_fn cruft_cb,
 329                                      each_loose_subdir_fn subdir_cb,
 330                                      void *data);
 331
 332/* Flags for for_each_*_object() below. */
 333enum for_each_object_flags {
 334        /* Iterate only over local objects, not alternates. */
 335        FOR_EACH_OBJECT_LOCAL_ONLY = (1<<0),
 336
 337        /* Only iterate over packs obtained from the promisor remote. */
 338        FOR_EACH_OBJECT_PROMISOR_ONLY = (1<<1),
 339
 340        /*
 341         * Visit objects within a pack in packfile order rather than .idx order
 342         */
 343        FOR_EACH_OBJECT_PACK_ORDER = (1<<2),
 344};
 345
 346/*
 347 * Iterate over all accessible loose objects without respect to
 348 * reachability. By default, this includes both local and alternate objects.
 349 * The order in which objects are visited is unspecified.
 350 *
 351 * Any flags specific to packs are ignored.
 352 */
 353int for_each_loose_object(each_loose_object_fn, void *,
 354                          enum for_each_object_flags flags);
 355
 356/*
 357 * Iterate over all accessible packed objects without respect to reachability.
 358 * By default, this includes both local and alternate packs.
 359 *
 360 * Note that some objects may appear twice if they are found in multiple packs.
 361 * Each pack is visited in an unspecified order. By default, objects within a
 362 * pack are visited in pack-idx order (i.e., sorted by oid).
 363 */
 364typedef int each_packed_object_fn(const struct object_id *oid,
 365                                  struct packed_git *pack,
 366                                  uint32_t pos,
 367                                  void *data);
 368int for_each_object_in_pack(struct packed_git *p,
 369                            each_packed_object_fn, void *data,
 370                            enum for_each_object_flags flags);
 371int for_each_packed_object(each_packed_object_fn, void *,
 372                           enum for_each_object_flags flags);
 373
 374#endif /* OBJECT_STORE_H */