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