dd3f9b75f04e6a23b235d415d15824aca8a43d20
[git/git.git] / object-store.h
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
10 struct 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[256];
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
32 void prepare_alt_odb(struct repository *r);
33 char *compute_alternate_path(const char *path, struct strbuf *err);
34 typedef int alt_odb_fn(struct object_directory *, void *);
35 int 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 */
41 void 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 */
48 void add_to_alternates_memory(const char *dir);
49
50 /*
51 * Populate and return the loose object cache array corresponding to the
52 * given object ID.
53 */
54 struct oid_array *odb_loose_cache(struct object_directory *odb,
55 const struct object_id *oid);
56
57 /* Empty the loose object cache for the specified object directory. */
58 void odb_clear_loose_cache(struct object_directory *odb);
59
60 struct packed_git {
61 struct packed_git *next;
62 struct list_head mru;
63 struct pack_window *windows;
64 off_t pack_size;
65 const void *index_data;
66 size_t index_size;
67 uint32_t num_objects;
68 uint32_t num_bad_objects;
69 unsigned char *bad_object_sha1;
70 int index_version;
71 time_t mtime;
72 int pack_fd;
73 int index; /* for builtin/pack-objects.c */
74 unsigned pack_local:1,
75 pack_keep:1,
76 pack_keep_in_core:1,
77 freshened:1,
78 do_not_close:1,
79 pack_promisor:1;
80 unsigned char sha1[20];
81 struct revindex_entry *revindex;
82 /* something like ".git/objects/pack/xxxxx.pack" */
83 char pack_name[FLEX_ARRAY]; /* more */
84 };
85
86 struct multi_pack_index;
87
88 struct raw_object_store {
89 /*
90 * Set of all object directories; the main directory is first (and
91 * cannot be NULL after initialization). Subsequent directories are
92 * alternates.
93 */
94 struct object_directory *odb;
95 struct object_directory **odb_tail;
96 int loaded_alternates;
97
98 /*
99 * A list of alternate object directories loaded from the environment;
100 * this should not generally need to be accessed directly, but will
101 * populate the "odb" list when prepare_alt_odb() is run.
102 */
103 char *alternate_db;
104
105 /*
106 * Objects that should be substituted by other objects
107 * (see git-replace(1)).
108 */
109 struct oidmap *replace_map;
110
111 struct commit_graph *commit_graph;
112 unsigned commit_graph_attempted : 1; /* if loading has been attempted */
113
114 /*
115 * private data
116 *
117 * should only be accessed directly by packfile.c and midx.c
118 */
119 struct multi_pack_index *multi_pack_index;
120
121 /*
122 * private data
123 *
124 * should only be accessed directly by packfile.c
125 */
126
127 struct packed_git *packed_git;
128 /* A most-recently-used ordered version of the packed_git list. */
129 struct list_head packed_git_mru;
130
131 /*
132 * A linked list containing all packfiles, starting with those
133 * contained in the multi_pack_index.
134 */
135 struct packed_git *all_packs;
136
137 /*
138 * A fast, rough count of the number of objects in the repository.
139 * These two fields are not meant for direct access. Use
140 * approximate_object_count() instead.
141 */
142 unsigned long approximate_object_count;
143 unsigned approximate_object_count_valid : 1;
144
145 /*
146 * Whether packed_git has already been populated with this repository's
147 * packs.
148 */
149 unsigned packed_git_initialized : 1;
150 };
151
152 struct raw_object_store *raw_object_store_new(void);
153 void raw_object_store_clear(struct raw_object_store *o);
154
155 /*
156 * Put in `buf` the name of the file in the local object database that
157 * would be used to store a loose object with the specified oid.
158 */
159 const char *loose_object_path(struct repository *r, struct strbuf *buf,
160 const struct object_id *oid);
161
162 void *map_loose_object(struct repository *r, const struct object_id *oid,
163 unsigned long *size);
164
165 extern void *read_object_file_extended(struct repository *r,
166 const struct object_id *oid,
167 enum object_type *type,
168 unsigned long *size, int lookup_replace);
169 static inline void *repo_read_object_file(struct repository *r,
170 const struct object_id *oid,
171 enum object_type *type,
172 unsigned long *size)
173 {
174 return read_object_file_extended(r, oid, type, size, 1);
175 }
176 #ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
177 #define read_object_file(oid, type, size) repo_read_object_file(the_repository, oid, type, size)
178 #endif
179
180 /* Read and unpack an object file into memory, write memory to an object file */
181 int oid_object_info(struct repository *r, const struct object_id *, unsigned long *);
182
183 extern int hash_object_file(const void *buf, unsigned long len,
184 const char *type, struct object_id *oid);
185
186 extern int write_object_file(const void *buf, unsigned long len,
187 const char *type, struct object_id *oid);
188
189 extern int hash_object_file_literally(const void *buf, unsigned long len,
190 const char *type, struct object_id *oid,
191 unsigned flags);
192
193 extern int pretend_object_file(void *, unsigned long, enum object_type,
194 struct object_id *oid);
195
196 extern int force_object_loose(const struct object_id *oid, time_t mtime);
197
198 /*
199 * Open the loose object at path, check its hash, and return the contents,
200 * type, and size. If the object is a blob, then "contents" may return NULL,
201 * to allow streaming of large blobs.
202 *
203 * Returns 0 on success, negative on error (details may be written to stderr).
204 */
205 int read_loose_object(const char *path,
206 const struct object_id *expected_oid,
207 enum object_type *type,
208 unsigned long *size,
209 void **contents);
210
211 #ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
212 #define has_sha1_file_with_flags(sha1, flags) repo_has_sha1_file_with_flags(the_repository, sha1, flags)
213 #define has_sha1_file(sha1) repo_has_sha1_file(the_repository, sha1)
214 #endif
215
216 /* Same as the above, except for struct object_id. */
217 int repo_has_object_file(struct repository *r, const struct object_id *oid);
218 int repo_has_object_file_with_flags(struct repository *r,
219 const struct object_id *oid, int flags);
220 #ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
221 #define has_object_file(oid) repo_has_object_file(the_repository, oid)
222 #define has_object_file_with_flags(oid, flags) repo_has_object_file_with_flags(the_repository, oid, flags)
223 #endif
224
225 /*
226 * Return true iff an alternate object database has a loose object
227 * with the specified name. This function does not respect replace
228 * references.
229 */
230 extern int has_loose_object_nonlocal(const struct object_id *);
231
232 extern void assert_oid_type(const struct object_id *oid, enum object_type expect);
233
234 struct object_info {
235 /* Request */
236 enum object_type *typep;
237 unsigned long *sizep;
238 off_t *disk_sizep;
239 unsigned char *delta_base_sha1;
240 struct strbuf *type_name;
241 void **contentp;
242
243 /* Response */
244 enum {
245 OI_CACHED,
246 OI_LOOSE,
247 OI_PACKED,
248 OI_DBCACHED
249 } whence;
250 union {
251 /*
252 * struct {
253 * ... Nothing to expose in this case
254 * } cached;
255 * struct {
256 * ... Nothing to expose in this case
257 * } loose;
258 */
259 struct {
260 struct packed_git *pack;
261 off_t offset;
262 unsigned int is_delta;
263 } packed;
264 } u;
265 };
266
267 /*
268 * Initializer for a "struct object_info" that wants no items. You may
269 * also memset() the memory to all-zeroes.
270 */
271 #define OBJECT_INFO_INIT {NULL}
272
273 /* Invoke lookup_replace_object() on the given hash */
274 #define OBJECT_INFO_LOOKUP_REPLACE 1
275 /* Allow reading from a loose object file of unknown/bogus type */
276 #define OBJECT_INFO_ALLOW_UNKNOWN_TYPE 2
277 /* Do not check cached storage */
278 #define OBJECT_INFO_SKIP_CACHED 4
279 /* Do not retry packed storage after checking packed and loose storage */
280 #define OBJECT_INFO_QUICK 8
281 /* Do not check loose object */
282 #define OBJECT_INFO_IGNORE_LOOSE 16
283 /*
284 * Do not attempt to fetch the object if missing (even if fetch_is_missing is
285 * nonzero). This is meant for bulk prefetching of missing blobs in a partial
286 * clone. Implies OBJECT_INFO_QUICK.
287 */
288 #define OBJECT_INFO_FOR_PREFETCH (32 + OBJECT_INFO_QUICK)
289
290 int oid_object_info_extended(struct repository *r,
291 const struct object_id *,
292 struct object_info *, unsigned flags);
293
294 /*
295 * Iterate over the files in the loose-object parts of the object
296 * directory "path", triggering the following callbacks:
297 *
298 * - loose_object is called for each loose object we find.
299 *
300 * - loose_cruft is called for any files that do not appear to be
301 * loose objects. Note that we only look in the loose object
302 * directories "objects/[0-9a-f]{2}/", so we will not report
303 * "objects/foobar" as cruft.
304 *
305 * - loose_subdir is called for each top-level hashed subdirectory
306 * of the object directory (e.g., "$OBJDIR/f0"). It is called
307 * after the objects in the directory are processed.
308 *
309 * Any callback that is NULL will be ignored. Callbacks returning non-zero
310 * will end the iteration.
311 *
312 * In the "buf" variant, "path" is a strbuf which will also be used as a
313 * scratch buffer, but restored to its original contents before
314 * the function returns.
315 */
316 typedef int each_loose_object_fn(const struct object_id *oid,
317 const char *path,
318 void *data);
319 typedef int each_loose_cruft_fn(const char *basename,
320 const char *path,
321 void *data);
322 typedef int each_loose_subdir_fn(unsigned int nr,
323 const char *path,
324 void *data);
325 int for_each_file_in_obj_subdir(unsigned int subdir_nr,
326 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 int for_each_loose_file_in_objdir(const char *path,
332 each_loose_object_fn obj_cb,
333 each_loose_cruft_fn cruft_cb,
334 each_loose_subdir_fn subdir_cb,
335 void *data);
336 int for_each_loose_file_in_objdir_buf(struct strbuf *path,
337 each_loose_object_fn obj_cb,
338 each_loose_cruft_fn cruft_cb,
339 each_loose_subdir_fn subdir_cb,
340 void *data);
341
342 /* Flags for for_each_*_object() below. */
343 enum for_each_object_flags {
344 /* Iterate only over local objects, not alternates. */
345 FOR_EACH_OBJECT_LOCAL_ONLY = (1<<0),
346
347 /* Only iterate over packs obtained from the promisor remote. */
348 FOR_EACH_OBJECT_PROMISOR_ONLY = (1<<1),
349
350 /*
351 * Visit objects within a pack in packfile order rather than .idx order
352 */
353 FOR_EACH_OBJECT_PACK_ORDER = (1<<2),
354 };
355
356 /*
357 * Iterate over all accessible loose objects without respect to
358 * reachability. By default, this includes both local and alternate objects.
359 * The order in which objects are visited is unspecified.
360 *
361 * Any flags specific to packs are ignored.
362 */
363 int for_each_loose_object(each_loose_object_fn, void *,
364 enum for_each_object_flags flags);
365
366 /*
367 * Iterate over all accessible packed objects without respect to reachability.
368 * By default, this includes both local and alternate packs.
369 *
370 * Note that some objects may appear twice if they are found in multiple packs.
371 * Each pack is visited in an unspecified order. By default, objects within a
372 * pack are visited in pack-idx order (i.e., sorted by oid).
373 */
374 typedef int each_packed_object_fn(const struct object_id *oid,
375 struct packed_git *pack,
376 uint32_t pos,
377 void *data);
378 int for_each_object_in_pack(struct packed_git *p,
379 each_packed_object_fn, void *data,
380 enum for_each_object_flags flags);
381 int for_each_packed_object(each_packed_object_fn, void *,
382 enum for_each_object_flags flags);
383
384 #endif /* OBJECT_STORE_H */