bf1e0cb7610d51054450eb522cb8a3b3f2117f91
   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         * our search for unique abbreviated hashes. Don't use it for tasks
  17         * requiring greater accuracy!
  18         *
  19         * Be sure to call odb_load_loose_cache() before using.
  20         */
  21        char loose_objects_subdir_seen[256];
  22        struct oid_array loose_objects_cache;
  23
  24        /*
  25         * Path to the alternative object store. If this is a relative path,
  26         * it is relative to the current working directory.
  27         */
  28        char *path;
  29};
  30
  31void prepare_alt_odb(struct repository *r);
  32char *compute_alternate_path(const char *path, struct strbuf *err);
  33typedef int alt_odb_fn(struct object_directory *, void *);
  34int foreach_alt_odb(alt_odb_fn, void*);
  35
  36/*
  37 * Add the directory to the on-disk alternates file; the new entry will also
  38 * take effect in the current process.
  39 */
  40void add_to_alternates_file(const char *dir);
  41
  42/*
  43 * Add the directory to the in-memory list of alternates (along with any
  44 * recursive alternates it points to), but do not modify the on-disk alternates
  45 * file.
  46 */
  47void add_to_alternates_memory(const char *dir);
  48
  49/*
  50 * Populate an odb's loose object cache for one particular subdirectory (i.e.,
  51 * the one that corresponds to the first byte of objects you're interested in,
  52 * from 0 to 255 inclusive).
  53 */
  54void odb_load_loose_cache(struct object_directory *odb, int subdir_nr);
  55
  56struct packed_git {
  57        struct packed_git *next;
  58        struct list_head mru;
  59        struct pack_window *windows;
  60        off_t pack_size;
  61        const void *index_data;
  62        size_t index_size;
  63        uint32_t num_objects;
  64        uint32_t num_bad_objects;
  65        unsigned char *bad_object_sha1;
  66        int index_version;
  67        time_t mtime;
  68        int pack_fd;
  69        int index;              /* for builtin/pack-objects.c */
  70        unsigned pack_local:1,
  71                 pack_keep:1,
  72                 pack_keep_in_core:1,
  73                 freshened:1,
  74                 do_not_close:1,
  75                 pack_promisor:1;
  76        unsigned char sha1[20];
  77        struct revindex_entry *revindex;
  78        /* something like ".git/objects/pack/xxxxx.pack" */
  79        char pack_name[FLEX_ARRAY]; /* more */
  80};
  81
  82struct multi_pack_index;
  83
  84struct raw_object_store {
  85        /*
  86         * Set of all object directories; the main directory is first (and
  87         * cannot be NULL after initialization). Subsequent directories are
  88         * alternates.
  89         */
  90        struct object_directory *odb;
  91        struct object_directory **odb_tail;
  92        int loaded_alternates;
  93
  94        /*
  95         * A list of alternate object directories loaded from the environment;
  96         * this should not generally need to be accessed directly, but will
  97         * populate the "odb" list when prepare_alt_odb() is run.
  98         */
  99        char *alternate_db;
 100
 101        /*
 102         * Objects that should be substituted by other objects
 103         * (see git-replace(1)).
 104         */
 105        struct oidmap *replace_map;
 106
 107        struct commit_graph *commit_graph;
 108        unsigned commit_graph_attempted : 1; /* if loading has been attempted */
 109
 110        /*
 111         * private data
 112         *
 113         * should only be accessed directly by packfile.c and midx.c
 114         */
 115        struct multi_pack_index *multi_pack_index;
 116
 117        /*
 118         * private data
 119         *
 120         * should only be accessed directly by packfile.c
 121         */
 122
 123        struct packed_git *packed_git;
 124        /* A most-recently-used ordered version of the packed_git list. */
 125        struct list_head packed_git_mru;
 126
 127        /*
 128         * A linked list containing all packfiles, starting with those
 129         * contained in the multi_pack_index.
 130         */
 131        struct packed_git *all_packs;
 132
 133        /*
 134         * A fast, rough count of the number of objects in the repository.
 135         * These two fields are not meant for direct access. Use
 136         * approximate_object_count() instead.
 137         */
 138        unsigned long approximate_object_count;
 139        unsigned approximate_object_count_valid : 1;
 140
 141        /*
 142         * Whether packed_git has already been populated with this repository's
 143         * packs.
 144         */
 145        unsigned packed_git_initialized : 1;
 146};
 147
 148struct raw_object_store *raw_object_store_new(void);
 149void raw_object_store_clear(struct raw_object_store *o);
 150
 151/*
 152 * Put in `buf` the name of the file in the local object database that
 153 * would be used to store a loose object with the specified sha1.
 154 */
 155const char *loose_object_path(struct repository *r, struct strbuf *buf, const unsigned char *sha1);
 156
 157void *map_sha1_file(struct repository *r, const unsigned char *sha1, unsigned long *size);
 158
 159extern void *read_object_file_extended(const struct object_id *oid,
 160                                       enum object_type *type,
 161                                       unsigned long *size, int lookup_replace);
 162static inline void *read_object_file(const struct object_id *oid, enum object_type *type, unsigned long *size)
 163{
 164        return read_object_file_extended(oid, type, size, 1);
 165}
 166
 167/* Read and unpack an object file into memory, write memory to an object file */
 168int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
 169
 170extern int hash_object_file(const void *buf, unsigned long len,
 171                            const char *type, struct object_id *oid);
 172
 173extern int write_object_file(const void *buf, unsigned long len,
 174                             const char *type, struct object_id *oid);
 175
 176extern int hash_object_file_literally(const void *buf, unsigned long len,
 177                                      const char *type, struct object_id *oid,
 178                                      unsigned flags);
 179
 180extern int pretend_object_file(void *, unsigned long, enum object_type,
 181                               struct object_id *oid);
 182
 183extern int force_object_loose(const struct object_id *oid, time_t mtime);
 184
 185/*
 186 * Open the loose object at path, check its hash, and return the contents,
 187 * type, and size. If the object is a blob, then "contents" may return NULL,
 188 * to allow streaming of large blobs.
 189 *
 190 * Returns 0 on success, negative on error (details may be written to stderr).
 191 */
 192int read_loose_object(const char *path,
 193                      const struct object_id *expected_oid,
 194                      enum object_type *type,
 195                      unsigned long *size,
 196                      void **contents);
 197
 198/*
 199 * Convenience for sha1_object_info_extended() with a NULL struct
 200 * object_info. OBJECT_INFO_SKIP_CACHED is automatically set; pass
 201 * nonzero flags to also set other flags.
 202 */
 203extern int has_sha1_file_with_flags(const unsigned char *sha1, int flags);
 204static inline int has_sha1_file(const unsigned char *sha1)
 205{
 206        return has_sha1_file_with_flags(sha1, 0);
 207}
 208
 209/* Same as the above, except for struct object_id. */
 210extern int has_object_file(const struct object_id *oid);
 211extern int has_object_file_with_flags(const struct object_id *oid, int flags);
 212
 213/*
 214 * Return true iff an alternate object database has a loose object
 215 * with the specified name.  This function does not respect replace
 216 * references.
 217 */
 218extern int has_loose_object_nonlocal(const struct object_id *);
 219
 220extern void assert_oid_type(const struct object_id *oid, enum object_type expect);
 221
 222struct object_info {
 223        /* Request */
 224        enum object_type *typep;
 225        unsigned long *sizep;
 226        off_t *disk_sizep;
 227        unsigned char *delta_base_sha1;
 228        struct strbuf *type_name;
 229        void **contentp;
 230
 231        /* Response */
 232        enum {
 233                OI_CACHED,
 234                OI_LOOSE,
 235                OI_PACKED,
 236                OI_DBCACHED
 237        } whence;
 238        union {
 239                /*
 240                 * struct {
 241                 *      ... Nothing to expose in this case
 242                 * } cached;
 243                 * struct {
 244                 *      ... Nothing to expose in this case
 245                 * } loose;
 246                 */
 247                struct {
 248                        struct packed_git *pack;
 249                        off_t offset;
 250                        unsigned int is_delta;
 251                } packed;
 252        } u;
 253};
 254
 255/*
 256 * Initializer for a "struct object_info" that wants no items. You may
 257 * also memset() the memory to all-zeroes.
 258 */
 259#define OBJECT_INFO_INIT {NULL}
 260
 261/* Invoke lookup_replace_object() on the given hash */
 262#define OBJECT_INFO_LOOKUP_REPLACE 1
 263/* Allow reading from a loose object file of unknown/bogus type */
 264#define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2
 265/* Do not check cached storage */
 266#define OBJECT_INFO_SKIP_CACHED 4
 267/* Do not retry packed storage after checking packed and loose storage */
 268#define OBJECT_INFO_QUICK 8
 269/* Do not check loose object */
 270#define OBJECT_INFO_IGNORE_LOOSE 16
 271
 272int oid_object_info_extended(struct repository *r,
 273                             const struct object_id *,
 274                             struct object_info *, unsigned flags);
 275
 276/*
 277 * Iterate over the files in the loose-object parts of the object
 278 * directory "path", triggering the following callbacks:
 279 *
 280 *  - loose_object is called for each loose object we find.
 281 *
 282 *  - loose_cruft is called for any files that do not appear to be
 283 *    loose objects. Note that we only look in the loose object
 284 *    directories "objects/[0-9a-f]{2}/", so we will not report
 285 *    "objects/foobar" as cruft.
 286 *
 287 *  - loose_subdir is called for each top-level hashed subdirectory
 288 *    of the object directory (e.g., "$OBJDIR/f0"). It is called
 289 *    after the objects in the directory are processed.
 290 *
 291 * Any callback that is NULL will be ignored. Callbacks returning non-zero
 292 * will end the iteration.
 293 *
 294 * In the "buf" variant, "path" is a strbuf which will also be used as a
 295 * scratch buffer, but restored to its original contents before
 296 * the function returns.
 297 */
 298typedef int each_loose_object_fn(const struct object_id *oid,
 299                                 const char *path,
 300                                 void *data);
 301typedef int each_loose_cruft_fn(const char *basename,
 302                                const char *path,
 303                                void *data);
 304typedef int each_loose_subdir_fn(unsigned int nr,
 305                                 const char *path,
 306                                 void *data);
 307int for_each_file_in_obj_subdir(unsigned int subdir_nr,
 308                                struct strbuf *path,
 309                                each_loose_object_fn obj_cb,
 310                                each_loose_cruft_fn cruft_cb,
 311                                each_loose_subdir_fn subdir_cb,
 312                                void *data);
 313int for_each_loose_file_in_objdir(const char *path,
 314                                  each_loose_object_fn obj_cb,
 315                                  each_loose_cruft_fn cruft_cb,
 316                                  each_loose_subdir_fn subdir_cb,
 317                                  void *data);
 318int for_each_loose_file_in_objdir_buf(struct strbuf *path,
 319                                      each_loose_object_fn obj_cb,
 320                                      each_loose_cruft_fn cruft_cb,
 321                                      each_loose_subdir_fn subdir_cb,
 322                                      void *data);
 323
 324/* Flags for for_each_*_object() below. */
 325enum for_each_object_flags {
 326        /* Iterate only over local objects, not alternates. */
 327        FOR_EACH_OBJECT_LOCAL_ONLY = (1<<0),
 328
 329        /* Only iterate over packs obtained from the promisor remote. */
 330        FOR_EACH_OBJECT_PROMISOR_ONLY = (1<<1),
 331
 332        /*
 333         * Visit objects within a pack in packfile order rather than .idx order
 334         */
 335        FOR_EACH_OBJECT_PACK_ORDER = (1<<2),
 336};
 337
 338/*
 339 * Iterate over all accessible loose objects without respect to
 340 * reachability. By default, this includes both local and alternate objects.
 341 * The order in which objects are visited is unspecified.
 342 *
 343 * Any flags specific to packs are ignored.
 344 */
 345int for_each_loose_object(each_loose_object_fn, void *,
 346                          enum for_each_object_flags flags);
 347
 348/*
 349 * Iterate over all accessible packed objects without respect to reachability.
 350 * By default, this includes both local and alternate packs.
 351 *
 352 * Note that some objects may appear twice if they are found in multiple packs.
 353 * Each pack is visited in an unspecified order. By default, objects within a
 354 * pack are visited in pack-idx order (i.e., sorted by oid).
 355 */
 356typedef int each_packed_object_fn(const struct object_id *oid,
 357                                  struct packed_git *pack,
 358                                  uint32_t pos,
 359                                  void *data);
 360int for_each_object_in_pack(struct packed_git *p,
 361                            each_packed_object_fn, void *data,
 362                            enum for_each_object_flags flags);
 363int for_each_packed_object(each_packed_object_fn, void *,
 364                           enum for_each_object_flags flags);
 365
 366#endif /* OBJECT_STORE_H */