aboutsummaryrefslogtreecommitdiff
path: root/refs.h
blob: 8c3d433a8a5b1b29f49d82e1c5799e8e3dc6e7a4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
#ifndef REFS_H
#define REFS_H

/*
 * A ref_transaction represents a collection of ref updates
 * that should succeed or fail together.
 *
 * Calling sequence
 * ----------------
 * - Allocate and initialize a `struct ref_transaction` by calling
 *   `ref_transaction_begin()`.
 *
 * - List intended ref updates by calling functions like
 *   `ref_transaction_update()` and `ref_transaction_create()`.
 *
 * - Call `ref_transaction_commit()` to execute the transaction.
 *   If this succeeds, the ref updates will have taken place and
 *   the transaction cannot be rolled back.
 *
 * - At any time call `ref_transaction_free()` to discard the
 *   transaction and free associated resources.  In particular,
 *   this rolls back the transaction if it has not been
 *   successfully committed.
 *
 * Error handling
 * --------------
 *
 * On error, transaction functions append a message about what
 * went wrong to the 'err' argument.  The message mentions what
 * ref was being updated (if any) when the error occurred so it
 * can be passed to 'die' or 'error' as-is.
 *
 * The message is appended to err without first clearing err.
 * err will not be '\n' terminated.
 */
struct ref_transaction;

/*
 * Bit values set in the flags argument passed to each_ref_fn():
 */

/* Reference is a symbolic reference. */
#define REF_ISSYMREF 0x01

/* Reference is a packed reference. */
#define REF_ISPACKED 0x02

/*
 * Reference cannot be resolved to an object name: dangling symbolic
 * reference (directly or indirectly), corrupt reference file,
 * reference exists but name is bad, or symbolic reference refers to
 * ill-formatted reference name.
 */
#define REF_ISBROKEN 0x04

/*
 * Reference name is not well formed.
 *
 * See git-check-ref-format(1) for the definition of well formed ref names.
 */
#define REF_BAD_NAME 0x08

/*
 * The signature for the callback function for the for_each_*()
 * functions below.  The memory pointed to by the refname and sha1
 * arguments is only guaranteed to be valid for the duration of a
 * single callback invocation.
 */
typedef int each_ref_fn(const char *refname,
			const struct object_id *oid, int flags, void *cb_data);

/*
 * The following functions invoke the specified callback function for
 * each reference indicated.  If the function ever returns a nonzero
 * value, stop the iteration and return that value.  Please note that
 * it is not safe to modify references while an iteration is in
 * progress, unless the same callback function invocation that
 * modifies the reference also returns a nonzero value to immediately
 * stop the iteration.
 */
extern int head_ref(each_ref_fn, void *);
extern int for_each_ref(each_ref_fn, void *);
extern int for_each_ref_in(const char *, each_ref_fn, void *);
extern int for_each_tag_ref(each_ref_fn, void *);
extern int for_each_branch_ref(each_ref_fn, void *);
extern int for_each_remote_ref(each_ref_fn, void *);
extern int for_each_replace_ref(each_ref_fn, void *);
extern int for_each_glob_ref(each_ref_fn, const char *pattern, void *);
extern int for_each_glob_ref_in(each_ref_fn, const char *pattern, const char* prefix, void *);

extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_ref_in_submodule(const char *submodule, const char *prefix,
		each_ref_fn fn, void *cb_data);
extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);

extern int head_ref_namespaced(each_ref_fn fn, void *cb_data);
extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);

static inline const char *has_glob_specials(const char *pattern)
{
	return strpbrk(pattern, "?*[");
}

/* can be used to learn about broken ref and symref */
extern int for_each_rawref(each_ref_fn, void *);

extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames);

/*
 * Lock the packed-refs file for writing.  Flags is passed to
 * hold_lock_file_for_update().  Return 0 on success.
 * Errno is set to something meaningful on error.
 */
extern int lock_packed_refs(int flags);

/*
 * Add a reference to the in-memory packed reference cache.  This may
 * only be called while the packed-refs file is locked (see
 * lock_packed_refs()).  To actually write the packed-refs file, call
 * commit_packed_refs().
 */
extern void add_packed_ref(const char *refname, const unsigned char *sha1);

/*
 * Write the current version of the packed refs cache from memory to
 * disk.  The packed-refs file must already be locked for writing (see
 * lock_packed_refs()).  Return zero on success.
 * Sets errno to something meaningful on error.
 */
extern int commit_packed_refs(void);

/*
 * Rollback the lockfile for the packed-refs file, and discard the
 * in-memory packed reference cache.  (The packed-refs file will be
 * read anew if it is needed again after this function is called.)
 */
extern void rollback_packed_refs(void);

/*
 * Flags for controlling behaviour of pack_refs()
 * PACK_REFS_PRUNE: Prune loose refs after packing
 * PACK_REFS_ALL:   Pack _all_ refs, not just tags and already packed refs
 */
#define PACK_REFS_PRUNE 0x0001
#define PACK_REFS_ALL   0x0002

/*
 * Write a packed-refs file for the current repository.
 * flags: Combination of the above PACK_REFS_* flags.
 */
int pack_refs(unsigned int flags);

/*
 * Rewrite the packed-refs file, omitting any refs listed in
 * 'refnames'. On error, packed-refs will be unchanged, the return
 * value is nonzero, and a message about the error is written to the
 * 'err' strbuf.
 *
 * The refs in 'refnames' needn't be sorted. `err` must not be NULL.
 */
extern int repack_without_refs(struct string_list *refnames,
			       struct strbuf *err);

extern int ref_exists(const char *);

extern int is_branch(const char *refname);

/*
 * If refname is a non-symbolic reference that refers to a tag object,
 * and the tag can be (recursively) dereferenced to a non-tag object,
 * store the SHA1 of the referred-to object to sha1 and return 0.  If
 * any of these conditions are not met, return a non-zero value.
 * Symbolic references are considered unpeelable, even if they
 * ultimately resolve to a peelable tag.
 */
extern int peel_ref(const char *refname, unsigned char *sha1);

/*
 * Flags controlling ref_transaction_update(), ref_transaction_create(), etc.
 * REF_NODEREF: act on the ref directly, instead of dereferencing
 *              symbolic references.
 *
 * Other flags are reserved for internal use.
 */
#define REF_NODEREF	0x01

/*
 * Setup reflog before using. Set errno to something meaningful on failure.
 */
int log_ref_setup(const char *refname, struct strbuf *logfile);

/** Reads log for the value of ref during at_time. **/
extern int read_ref_at(const char *refname, unsigned int flags,
		       unsigned long at_time, int cnt,
		       unsigned char *sha1, char **msg,
		       unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);

/** Check if a particular reflog exists */
extern int reflog_exists(const char *refname);

/** Delete a reflog */
extern int delete_reflog(const char *refname);

/* iterate over reflog entries */
typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *);
int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);

/*
 * Calls the specified function for each reflog file until it returns nonzero,
 * and returns the value
 */
extern int for_each_reflog(each_ref_fn, void *);

#define REFNAME_ALLOW_ONELEVEL 1
#define REFNAME_REFSPEC_PATTERN 2

/*
 * Return 0 iff refname has the correct format for a refname according
 * to the rules described in Documentation/git-check-ref-format.txt.
 * If REFNAME_ALLOW_ONELEVEL is set in flags, then accept one-level
 * reference names.  If REFNAME_REFSPEC_PATTERN is set in flags, then
 * allow a "*" wildcard character in place of one of the name
 * components.  No leading or repeated slashes are accepted.
 */
extern int check_refname_format(const char *refname, int flags);

extern const char *prettify_refname(const char *refname);
extern char *shorten_unambiguous_ref(const char *refname, int strict);

/** rename ref, return 0 on success **/
extern int rename_ref(const char *oldref, const char *newref, const char *logmsg);

/**
 * Resolve refname in the nested "gitlink" repository that is located
 * at path.  If the resolution is successful, return 0 and set sha1 to
 * the name of the object; otherwise, return a non-zero value.
 */
extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1);

enum action_on_err {
	UPDATE_REFS_MSG_ON_ERR,
	UPDATE_REFS_DIE_ON_ERR,
	UPDATE_REFS_QUIET_ON_ERR
};

/*
 * Begin a reference transaction.  The reference transaction must
 * be freed by calling ref_transaction_free().
 */
struct ref_transaction *ref_transaction_begin(struct strbuf *err);

/*
 * Reference transaction updates
 *
 * The following four functions add a reference check or update to a
 * ref_transaction.  They have some common similar parameters:
 *
 *     transaction -- a pointer to an open ref_transaction, obtained
 *         from ref_transaction_begin().
 *
 *     refname -- the name of the reference to be affected.
 *
 *     flags -- flags affecting the update, passed to
 *         update_ref_lock(). Can be REF_NODEREF, which means that
 *         symbolic references should not be followed.
 *
 *     msg -- a message describing the change (for the reflog).
 *
 *     err -- a strbuf for receiving a description of any error that
 *         might have occured.
 *
 * The functions make internal copies of refname and msg, so the
 * caller retains ownership of these parameters.
 *
 * The functions return 0 on success and non-zero on failure. A
 * failure means that the transaction as a whole has failed and needs
 * to be rolled back.
 */

/*
 * Add a reference update to transaction. new_sha1 is the value that
 * the reference should have after the update, or null_sha1 if it
 * should be deleted. If new_sha1 is NULL, then the reference is not
 * changed at all. old_sha1 is the value that the reference must have
 * before the update, or null_sha1 if it must not have existed
 * beforehand. The old value is checked after the lock is taken to
 * prevent races. If the old value doesn't agree with old_sha1, the
 * whole transaction fails. If old_sha1 is NULL, then the previous
 * value is not checked.
 *
 * See the above comment "Reference transaction updates" for more
 * information.
 */
int ref_transaction_update(struct ref_transaction *transaction,
			   const char *refname,
			   const unsigned char *new_sha1,
			   const unsigned char *old_sha1,
			   unsigned int flags, const char *msg,
			   struct strbuf *err);

/*
 * Add a reference creation to transaction. new_sha1 is the value that
 * the reference should have after the update; it must not be
 * null_sha1. It is verified that the reference does not exist
 * already.
 *
 * See the above comment "Reference transaction updates" for more
 * information.
 */
int ref_transaction_create(struct ref_transaction *transaction,
			   const char *refname,
			   const unsigned char *new_sha1,
			   unsigned int flags, const char *msg,
			   struct strbuf *err);

/*
 * Add a reference deletion to transaction. If old_sha1 is non-NULL,
 * then it holds the value that the reference should have had before
 * the update (which must not be null_sha1).
 *
 * See the above comment "Reference transaction updates" for more
 * information.
 */
int ref_transaction_delete(struct ref_transaction *transaction,
			   const char *refname,
			   const unsigned char *old_sha1,
			   unsigned int flags, const char *msg,
			   struct strbuf *err);

/*
 * Verify, within a transaction, that refname has the value old_sha1,
 * or, if old_sha1 is null_sha1, then verify that the reference
 * doesn't exist. old_sha1 must be non-NULL.
 *
 * See the above comment "Reference transaction updates" for more
 * information.
 */
int ref_transaction_verify(struct ref_transaction *transaction,
			   const char *refname,
			   const unsigned char *old_sha1,
			   unsigned int flags,
			   struct strbuf *err);

/*
 * Commit all of the changes that have been queued in transaction, as
 * atomically as possible.
 *
 * Returns 0 for success, or one of the below error codes for errors.
 */
/* Naming conflict (for example, the ref names A and A/B conflict). */
#define TRANSACTION_NAME_CONFLICT -1
/* All other errors. */
#define TRANSACTION_GENERIC_ERROR -2
int ref_transaction_commit(struct ref_transaction *transaction,
			   struct strbuf *err);

/*
 * Free an existing transaction and all associated data.
 */
void ref_transaction_free(struct ref_transaction *transaction);

/**
 * Lock, update, and unlock a single reference. This function
 * basically does a transaction containing a single call to
 * ref_transaction_update(). The parameters to this function have the
 * same meaning as the corresponding parameters to
 * ref_transaction_update(). Handle errors as requested by the `onerr`
 * argument.
 */
int update_ref(const char *msg, const char *refname,
	       const unsigned char *new_sha1, const unsigned char *old_sha1,
	       unsigned int flags, enum action_on_err onerr);

extern int parse_hide_refs_config(const char *var, const char *value, const char *);
extern int ref_is_hidden(const char *);

enum expire_reflog_flags {
	EXPIRE_REFLOGS_DRY_RUN = 1 << 0,
	EXPIRE_REFLOGS_UPDATE_REF = 1 << 1,
	EXPIRE_REFLOGS_VERBOSE = 1 << 2,
	EXPIRE_REFLOGS_REWRITE = 1 << 3
};

/*
 * The following interface is used for reflog expiration. The caller
 * calls reflog_expire(), supplying it with three callback functions,
 * of the following types. The callback functions define the
 * expiration policy that is desired.
 *
 * reflog_expiry_prepare_fn -- Called once after the reference is
 *     locked.
 *
 * reflog_expiry_should_prune_fn -- Called once for each entry in the
 *     existing reflog. It should return true iff that entry should be
 *     pruned.
 *
 * reflog_expiry_cleanup_fn -- Called once before the reference is
 *     unlocked again.
 */
typedef void reflog_expiry_prepare_fn(const char *refname,
				      const unsigned char *sha1,
				      void *cb_data);
typedef int reflog_expiry_should_prune_fn(unsigned char *osha1,
					  unsigned char *nsha1,
					  const char *email,
					  unsigned long timestamp, int tz,
					  const char *message, void *cb_data);
typedef void reflog_expiry_cleanup_fn(void *cb_data);

/*
 * Expire reflog entries for the specified reference. sha1 is the old
 * value of the reference. flags is a combination of the constants in
 * enum expire_reflog_flags. The three function pointers are described
 * above. On success, return zero.
 */
extern int reflog_expire(const char *refname, const unsigned char *sha1,
			 unsigned int flags,
			 reflog_expiry_prepare_fn prepare_fn,
			 reflog_expiry_should_prune_fn should_prune_fn,
			 reflog_expiry_cleanup_fn cleanup_fn,
			 void *policy_cb_data);

#endif /* REFS_H */