30faf7b3919162cd6eeaaa87eb3aeb18f74dc6fa
   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 searching
  15         * for unique abbreviated hashes.  This cache is never
  16         * invalidated, thus it's racy and not necessarily accurate.
  17         * That's fine for its purpose; don't use it for tasks requiring
  18         * greater accuracy!
  19         */
  20        char loose_objects_subdir_seen[256];
  21        struct oid_array loose_objects_cache;
  22
  23        /*
  24         * Path to the alternative object store. If this is a relative path,
  25         * it is relative to the current working directory.
  26         */
  27        char *path;
  28};
  29
  30void prepare_alt_odb(struct repository *r);
  31char *compute_alternate_path(const char *path, struct strbuf *err);
  32typedef int alt_odb_fn(struct object_directory *, void *);
  33int foreach_alt_odb(alt_odb_fn, void*);
  34
  35/*
  36 * Add the directory to the on-disk alternates file; the new entry will also
  37 * take effect in the current process.
  38 */
  39void add_to_alternates_file(const char *dir);
  40
  41/*
  42 * Add the directory to the in-memory list of alternates (along with any
  43 * recursive alternates it points to), but do not modify the on-disk alternates
  44 * file.
  45 */
  46void add_to_alternates_memory(const char *dir);
  47
  48struct packed_git {
  49        struct packed_git *next;
  50        struct list_head mru;
  51        struct pack_window *windows;
  52        off_t pack_size;
  53        const void *index_data;
  54        size_t index_size;
  55        uint32_t num_objects;
  56        uint32_t num_bad_objects;
  57        unsigned char *bad_object_sha1;
  58        int index_version;
  59        time_t mtime;
  60        int pack_fd;
  61        int index;              /* for builtin/pack-objects.c */
  62        unsigned pack_local:1,
  63                 pack_keep:1,
  64                 pack_keep_in_core:1,
  65                 freshened:1,
  66                 do_not_close:1,
  67                 pack_promisor:1;
  68        unsigned char sha1[20];
  69        struct revindex_entry *revindex;
  70        /* something like ".git/objects/pack/xxxxx.pack" */
  71        char pack_name[FLEX_ARRAY]; /* more */
  72};
  73
  74struct multi_pack_index;
  75
  76struct raw_object_store {
  77        /*
  78         * Set of all object directories; the main directory is first (and
  79         * cannot be NULL after initialization). Subsequent directories are
  80         * alternates.
  81         */
  82        struct object_directory *odb;
  83        struct object_directory **odb_tail;
  84        int loaded_alternates;
  85
  86        /*
  87         * A list of alternate object directories loaded from the environment;
  88         * this should not generally need to be accessed directly, but will
  89         * populate the "odb" list when prepare_alt_odb() is run.
  90         */
  91        char *alternate_db;
  92
  93        /*
  94         * Objects that should be substituted by other objects
  95         * (see git-replace(1)).
  96         */
  97        struct oidmap *replace_map;
  98
  99        struct commit_graph *commit_graph;
 100        unsigned commit_graph_attempted : 1; /* if loading has been attempted */
 101
 102        /*
 103         * private data
 104         *
 105         * should only be accessed directly by packfile.c and midx.c
 106         */
 107        struct multi_pack_index *multi_pack_index;
 108
 109        /*
 110         * private data
 111         *
 112         * should only be accessed directly by packfile.c
 113         */
 114
 115        struct packed_git *packed_git;
 116        /* A most-recently-used ordered version of the packed_git list. */
 117        struct list_head packed_git_mru;
 118
 119        /*
 120         * A linked list containing all packfiles, starting with those
 121         * contained in the multi_pack_index.
 122         */
 123        struct packed_git *all_packs;
 124
 125        /*
 126         * A fast, rough count of the number of objects in the repository.
 127         * These two fields are not meant for direct access. Use
 128         * approximate_object_count() instead.
 129         */
 130        unsigned long approximate_object_count;
 131        unsigned approximate_object_count_valid : 1;
 132
 133        /*
 134         * Whether packed_git has already been populated with this repository's
 135         * packs.
 136         */
 137        unsigned packed_git_initialized : 1;
 138};
 139
 140struct raw_object_store *raw_object_store_new(void);
 141void raw_object_store_clear(struct raw_object_store *o);
 142
 143/*
 144 * Put in `buf` the name of the file in the local object database that
 145 * would be used to store a loose object with the specified sha1.
 146 */
 147const char *loose_object_path(struct repository *r, struct strbuf *buf, const unsigned char *sha1);
 148
 149void *map_sha1_file(struct repository *r, const unsigned char *sha1, unsigned long *size);
 150
 151extern void *read_object_file_extended(const struct object_id *oid,
 152                                       enum object_type *type,
 153                                       unsigned long *size, int lookup_replace);
 154static inline void *read_object_file(const struct object_id *oid, enum object_type *type, unsigned long *size)
 155{
 156        return read_object_file_extended(oid, type, size, 1);
 157}
 158
 159/* Read and unpack an object file into memory, write memory to an object file */
 160int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
 161
 162extern int hash_object_file(const void *buf, unsigned long len,
 163                            const char *type, struct object_id *oid);
 164
 165extern int write_object_file(const void *buf, unsigned long len,
 166                             const char *type, struct object_id *oid);
 167
 168extern int hash_object_file_literally(const void *buf, unsigned long len,
 169                                      const char *type, struct object_id *oid,
 170                                      unsigned flags);
 171
 172extern int pretend_object_file(void *, unsigned long, enum object_type,
 173                               struct object_id *oid);
 174
 175extern int force_object_loose(const struct object_id *oid, time_t mtime);
 176
 177/*
 178 * Open the loose object at path, check its hash, and return the contents,
 179 * type, and size. If the object is a blob, then "contents" may return NULL,
 180 * to allow streaming of large blobs.
 181 *
 182 * Returns 0 on success, negative on error (details may be written to stderr).
 183 */
 184int read_loose_object(const char *path,
 185                      const struct object_id *expected_oid,
 186                      enum object_type *type,
 187                      unsigned long *size,
 188                      void **contents);
 189
 190/*
 191 * Convenience for sha1_object_info_extended() with a NULL struct
 192 * object_info. OBJECT_INFO_SKIP_CACHED is automatically set; pass
 193 * nonzero flags to also set other flags.
 194 */
 195extern int has_sha1_file_with_flags(const unsigned char *sha1, int flags);
 196static inline int has_sha1_file(const unsigned char *sha1)
 197{
 198        return has_sha1_file_with_flags(sha1, 0);
 199}
 200
 201/* Same as the above, except for struct object_id. */
 202extern int has_object_file(const struct object_id *oid);
 203extern int has_object_file_with_flags(const struct object_id *oid, int flags);
 204
 205/*
 206 * Return true iff an alternate object database has a loose object
 207 * with the specified name.  This function does not respect replace
 208 * references.
 209 */
 210extern int has_loose_object_nonlocal(const struct object_id *);
 211
 212extern void assert_oid_type(const struct object_id *oid, enum object_type expect);
 213
 214struct object_info {
 215        /* Request */
 216        enum object_type *typep;
 217        unsigned long *sizep;
 218        off_t *disk_sizep;
 219        unsigned char *delta_base_sha1;
 220        struct strbuf *type_name;
 221        void **contentp;
 222
 223        /* Response */
 224        enum {
 225                OI_CACHED,
 226                OI_LOOSE,
 227                OI_PACKED,
 228                OI_DBCACHED
 229        } whence;
 230        union {
 231                /*
 232                 * struct {
 233                 *      ... Nothing to expose in this case
 234                 * } cached;
 235                 * struct {
 236                 *      ... Nothing to expose in this case
 237                 * } loose;
 238                 */
 239                struct {
 240                        struct packed_git *pack;
 241                        off_t offset;
 242                        unsigned int is_delta;
 243                } packed;
 244        } u;
 245};
 246
 247/*
 248 * Initializer for a "struct object_info" that wants no items. You may
 249 * also memset() the memory to all-zeroes.
 250 */
 251#define OBJECT_INFO_INIT {NULL}
 252
 253/* Invoke lookup_replace_object() on the given hash */
 254#define OBJECT_INFO_LOOKUP_REPLACE 1
 255/* Allow reading from a loose object file of unknown/bogus type */
 256#define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2
 257/* Do not check cached storage */
 258#define OBJECT_INFO_SKIP_CACHED 4
 259/* Do not retry packed storage after checking packed and loose storage */
 260#define OBJECT_INFO_QUICK 8
 261/* Do not check loose object */
 262#define OBJECT_INFO_IGNORE_LOOSE 16
 263
 264int oid_object_info_extended(struct repository *r,
 265                             const struct object_id *,
 266                             struct object_info *, unsigned flags);
 267
 268/*
 269 * Iterate over the files in the loose-object parts of the object
 270 * directory "path", triggering the following callbacks:
 271 *
 272 *  - loose_object is called for each loose object we find.
 273 *
 274 *  - loose_cruft is called for any files that do not appear to be
 275 *    loose objects. Note that we only look in the loose object
 276 *    directories "objects/[0-9a-f]{2}/", so we will not report
 277 *    "objects/foobar" as cruft.
 278 *
 279 *  - loose_subdir is called for each top-level hashed subdirectory
 280 *    of the object directory (e.g., "$OBJDIR/f0"). It is called
 281 *    after the objects in the directory are processed.
 282 *
 283 * Any callback that is NULL will be ignored. Callbacks returning non-zero
 284 * will end the iteration.
 285 *
 286 * In the "buf" variant, "path" is a strbuf which will also be used as a
 287 * scratch buffer, but restored to its original contents before
 288 * the function returns.
 289 */
 290typedef int each_loose_object_fn(const struct object_id *oid,
 291                                 const char *path,
 292                                 void *data);
 293typedef int each_loose_cruft_fn(const char *basename,
 294                                const char *path,
 295                                void *data);
 296typedef int each_loose_subdir_fn(unsigned int nr,
 297                                 const char *path,
 298                                 void *data);
 299int for_each_file_in_obj_subdir(unsigned int subdir_nr,
 300                                struct strbuf *path,
 301                                each_loose_object_fn obj_cb,
 302                                each_loose_cruft_fn cruft_cb,
 303                                each_loose_subdir_fn subdir_cb,
 304                                void *data);
 305int for_each_loose_file_in_objdir(const char *path,
 306                                  each_loose_object_fn obj_cb,
 307                                  each_loose_cruft_fn cruft_cb,
 308                                  each_loose_subdir_fn subdir_cb,
 309                                  void *data);
 310int for_each_loose_file_in_objdir_buf(struct strbuf *path,
 311                                      each_loose_object_fn obj_cb,
 312                                      each_loose_cruft_fn cruft_cb,
 313                                      each_loose_subdir_fn subdir_cb,
 314                                      void *data);
 315
 316/* Flags for for_each_*_object() below. */
 317enum for_each_object_flags {
 318        /* Iterate only over local objects, not alternates. */
 319        FOR_EACH_OBJECT_LOCAL_ONLY = (1<<0),
 320
 321        /* Only iterate over packs obtained from the promisor remote. */
 322        FOR_EACH_OBJECT_PROMISOR_ONLY = (1<<1),
 323
 324        /*
 325         * Visit objects within a pack in packfile order rather than .idx order
 326         */
 327        FOR_EACH_OBJECT_PACK_ORDER = (1<<2),
 328};
 329
 330/*
 331 * Iterate over all accessible loose objects without respect to
 332 * reachability. By default, this includes both local and alternate objects.
 333 * The order in which objects are visited is unspecified.
 334 *
 335 * Any flags specific to packs are ignored.
 336 */
 337int for_each_loose_object(each_loose_object_fn, void *,
 338                          enum for_each_object_flags flags);
 339
 340/*
 341 * Iterate over all accessible packed objects without respect to reachability.
 342 * By default, this includes both local and alternate packs.
 343 *
 344 * Note that some objects may appear twice if they are found in multiple packs.
 345 * Each pack is visited in an unspecified order. By default, objects within a
 346 * pack are visited in pack-idx order (i.e., sorted by oid).
 347 */
 348typedef int each_packed_object_fn(const struct object_id *oid,
 349                                  struct packed_git *pack,
 350                                  uint32_t pos,
 351                                  void *data);
 352int for_each_object_in_pack(struct packed_git *p,
 353                            each_packed_object_fn, void *data,
 354                            enum for_each_object_flags flags);
 355int for_each_packed_object(each_packed_object_fn, void *,
 356                           enum for_each_object_flags flags);
 357
 358#endif /* OBJECT_STORE_H */