summaryrefslogtreecommitdiff
path: root/reflog.c
blob: 135a1a6e41cf51afaf2ffc730a225409147f81b0 (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
429
430
431
432
433
434
#include "cache.h"
#include "object-store.h"
#include "reflog.h"
#include "refs.h"
#include "revision.h"
#include "worktree.h"
 
/* Remember to update object flag allocation in object.h */
#define INCOMPLETE	(1u<<10)
#define STUDYING	(1u<<11)
#define REACHABLE	(1u<<12)
 
static int tree_is_complete(const struct object_id *oid)
{
	struct tree_desc desc;
	struct name_entry entry;
	int complete;
	struct tree *tree;
 
	tree = lookup_tree(the_repository, oid);
	if (!tree)
		return 0;
	if (tree->object.flags & SEEN)
		return 1;
	if (tree->object.flags & INCOMPLETE)
		return 0;
 
	if (!tree->buffer) {
		enum object_type type;
		unsigned long size;
		void *data = read_object_file(oid, &type, &size);
		if (!data) {
			tree->object.flags |= INCOMPLETE;
			return 0;
		}
		tree->buffer = data;
		tree->size = size;
	}
	init_tree_desc(&desc, tree->buffer, tree->size);
	complete = 1;
	while (tree_entry(&desc, &entry)) {
		if (!has_object_file(&entry.oid) ||
		    (S_ISDIR(entry.mode) && !tree_is_complete(&entry.oid))) {
			tree->object.flags |= INCOMPLETE;
			complete = 0;
		}
	}
	free_tree_buffer(tree);
 
	if (complete)
		tree->object.flags |= SEEN;
	return complete;
}
 
static int commit_is_complete(struct commit *commit)
{
	struct object_array study;
	struct object_array found;
	int is_incomplete = 0;
	int i;
 
	/* early return */
	if (commit->object.flags & SEEN)
		return 1;
	if (commit->object.flags & INCOMPLETE)
		return 0;
	/*
	 * Find all commits that are reachable and are not marked as
	 * SEEN.  Then make sure the trees and blobs contained are
	 * complete.  After that, mark these commits also as SEEN.
	 * If some of the objects that are needed to complete this
	 * commit are missing, mark this commit as INCOMPLETE.
	 */
	memset(&study, 0, sizeof(study));
	memset(&found, 0, sizeof(found));
	add_object_array(&commit->object, NULL, &study);
	add_object_array(&commit->object, NULL, &found);
	commit->object.flags |= STUDYING;
	while (study.nr) {
		struct commit *c;
		struct commit_list *parent;
 
		c = (struct commit *)object_array_pop(&study);
		if (!c->object.parsed && !parse_object(the_repository, &c->object.oid))
			c->object.flags |= INCOMPLETE;
 
		if (c->object.flags & INCOMPLETE) {
			is_incomplete = 1;
			break;
		}
		else if (c->object.flags & SEEN)
			continue;
		for (parent = c->parents; parent; parent = parent->next) {
			struct commit *p = parent->item;
			if (p->object.flags & STUDYING)
				continue;
			p->object.flags |= STUDYING;
			add_object_array(&p->object, NULL, &study);
			add_object_array(&p->object, NULL, &found);
		}
	}
	if (!is_incomplete) {
		/*
		 * make sure all commits in "found" array have all the
		 * necessary objects.
		 */
		for (i = 0; i < found.nr; i++) {
			struct commit *c =
				(struct commit *)found.objects[i].item;
			if (!tree_is_complete(get_commit_tree_oid(c))) {
				is_incomplete = 1;
				c->object.flags |= INCOMPLETE;
			}
		}
		if (!is_incomplete) {
			/* mark all found commits as complete, iow SEEN */
			for (i = 0; i < found.nr; i++)
				found.objects[i].item->flags |= SEEN;
		}
	}
	/* clear flags from the objects we traversed */
	for (i = 0; i < found.nr; i++)
		found.objects[i].item->flags &= ~STUDYING;
	if (is_incomplete)
		commit->object.flags |= INCOMPLETE;
	else {
		/*
		 * If we come here, we have (1) traversed the ancestry chain
		 * from the "commit" until we reach SEEN commits (which are
		 * known to be complete), and (2) made sure that the commits
		 * encountered during the above traversal refer to trees that
		 * are complete.  Which means that we know *all* the commits
		 * we have seen during this process are complete.
		 */
		for (i = 0; i < found.nr; i++)
			found.objects[i].item->flags |= SEEN;
	}
	/* free object arrays */
	object_array_clear(&study);
	object_array_clear(&found);
	return !is_incomplete;
}
 
static int keep_entry(struct commit **it, struct object_id *oid)
{
	struct commit *commit;
 
	if (is_null_oid(oid))
		return 1;
	commit = lookup_commit_reference_gently(the_repository, oid, 1);
	if (!commit)
		return 0;
 
	/*
	 * Make sure everything in this commit exists.
	 *
	 * We have walked all the objects reachable from the refs
	 * and cache earlier.  The commits reachable by this commit
	 * must meet SEEN commits -- and then we should mark them as
	 * SEEN as well.
	 */
	if (!commit_is_complete(commit))
		return 0;
	*it = commit;
	return 1;
}
 
/*
 * Starting from commits in the cb->mark_list, mark commits that are
 * reachable from them.  Stop the traversal at commits older than
 * the expire_limit and queue them back, so that the caller can call
 * us again to restart the traversal with longer expire_limit.
 */
static void mark_reachable(struct expire_reflog_policy_cb *cb)
{
	struct commit_list *pending;
	timestamp_t expire_limit = cb->mark_limit;
	struct commit_list *leftover = NULL;
 
	for (pending = cb->mark_list; pending; pending = pending->next)
		pending->item->object.flags &= ~REACHABLE;
 
	pending = cb->mark_list;
	while (pending) {
		struct commit_list *parent;
		struct commit *commit = pop_commit(&pending);
		if (commit->object.flags & REACHABLE)
			continue;
		if (parse_commit(commit))
			continue;
		commit->object.flags |= REACHABLE;
		if (commit->date < expire_limit) {
			commit_list_insert(commit, &leftover);
			continue;
		}
		commit->object.flags |= REACHABLE;
		parent = commit->parents;
		while (parent) {
			commit = parent->item;
			parent = parent->next;
			if (commit->object.flags & REACHABLE)
				continue;
			commit_list_insert(commit, &pending);
		}
	}
	cb->mark_list = leftover;
}
 
static int unreachable(struct expire_reflog_policy_cb *cb, struct commit *commit, struct object_id *oid)
{
	/*
	 * We may or may not have the commit yet - if not, look it
	 * up using the supplied sha1.
	 */
	if (!commit) {
		if (is_null_oid(oid))
			return 0;
 
		commit = lookup_commit_reference_gently(the_repository, oid,
							1);
 
		/* Not a commit -- keep it */
		if (!commit)
			return 0;
	}
 
	/* Reachable from the current ref?  Don't prune. */
	if (commit->object.flags & REACHABLE)
		return 0;
 
	if (cb->mark_list && cb->mark_limit) {
		cb->mark_limit = 0; /* dig down to the root */
		mark_reachable(cb);
	}
 
	return !(commit->object.flags & REACHABLE);
}
 
/*
 * Return true iff the specified reflog entry should be expired.
 */
int should_expire_reflog_ent(struct object_id *ooid, struct object_id *noid,
			     const char *email, timestamp_t timestamp, int tz,
			     const char *message, void *cb_data)
{
	struct expire_reflog_policy_cb *cb = cb_data;
	struct commit *old_commit, *new_commit;
 
	if (timestamp < cb->cmd.expire_total)
		return 1;
 
	old_commit = new_commit = NULL;
	if (cb->cmd.stalefix &&
	    (!keep_entry(&old_commit, ooid) || !keep_entry(&new_commit, noid)))
		return 1;
 
	if (timestamp < cb->cmd.expire_unreachable) {
		switch (cb->unreachable_expire_kind) {
		case UE_ALWAYS:
			return 1;
		case UE_NORMAL:
		case UE_HEAD:
			if (unreachable(cb, old_commit, ooid) || unreachable(cb, new_commit, noid))
				return 1;
			break;
		}
	}
 
	if (cb->cmd.recno && --(cb->cmd.recno) == 0)
		return 1;
 
	return 0;
}
 
int should_expire_reflog_ent_verbose(struct object_id *ooid,
				     struct object_id *noid,
				     const char *email,
				     timestamp_t timestamp, int tz,
				     const char *message, void *cb_data)
{
	struct expire_reflog_policy_cb *cb = cb_data;
	int expire;
 
	expire = should_expire_reflog_ent(ooid, noid, email, timestamp, tz,
					  message, cb);
 
	if (!expire)
		printf("keep %s", message);
	else if (cb->dry_run)
		printf("would prune %s", message);
	else
		printf("prune %s", message);
 
	return expire;
}
 
static int push_tip_to_list(const char *refname, const struct object_id *oid,
			    int flags, void *cb_data)
{
	struct commit_list **list = cb_data;
	struct commit *tip_commit;
	if (flags & REF_ISSYMREF)
		return 0;
	tip_commit = lookup_commit_reference_gently(the_repository, oid, 1);
	if (!tip_commit)
		return 0;
	commit_list_insert(tip_commit, list);
	return 0;
}
 
static int is_head(const char *refname)
{
	switch (ref_type(refname)) {
	case REF_TYPE_OTHER_PSEUDOREF:
	case REF_TYPE_MAIN_PSEUDOREF:
		if (parse_worktree_ref(refname, NULL, NULL, &refname))
			BUG("not a worktree ref: %s", refname);
		break;
	default:
		break;
	}
	return !strcmp(refname, "HEAD");
}
 
void reflog_expiry_prepare(const char *refname,
			   const struct object_id *oid,
			   void *cb_data)
{
	struct expire_reflog_policy_cb *cb = cb_data;
	struct commit_list *elem;
	struct commit *commit = NULL;
 
	if (!cb->cmd.expire_unreachable || is_head(refname)) {
		cb->unreachable_expire_kind = UE_HEAD;
	} else {
		commit = lookup_commit(the_repository, oid);
		if (commit && is_null_oid(&commit->object.oid))
			commit = NULL;
		cb->unreachable_expire_kind = commit ? UE_NORMAL : UE_ALWAYS;
	}
 
	if (cb->cmd.expire_unreachable <= cb->cmd.expire_total)
		cb->unreachable_expire_kind = UE_ALWAYS;
 
	switch (cb->unreachable_expire_kind) {
	case UE_ALWAYS:
		return;
	case UE_HEAD:
		for_each_ref(push_tip_to_list, &cb->tips);
		for (elem = cb->tips; elem; elem = elem->next)
			commit_list_insert(elem->item, &cb->mark_list);
		break;
	case UE_NORMAL:
		commit_list_insert(commit, &cb->mark_list);
		/* For reflog_expiry_cleanup() below */
		cb->tip_commit = commit;
	}
	cb->mark_limit = cb->cmd.expire_total;
	mark_reachable(cb);
}
 
void reflog_expiry_cleanup(void *cb_data)
{
	struct expire_reflog_policy_cb *cb = cb_data;
	struct commit_list *elem;
 
	switch (cb->unreachable_expire_kind) {
	case UE_ALWAYS:
		return;
	case UE_HEAD:
		for (elem = cb->tips; elem; elem = elem->next)
			clear_commit_marks(elem->item, REACHABLE);
		free_commit_list(cb->tips);
		break;
	case UE_NORMAL:
		clear_commit_marks(cb->tip_commit, REACHABLE);
		break;
	}
}
 
int count_reflog_ent(struct object_id *ooid, struct object_id *noid,
		     const char *email, timestamp_t timestamp, int tz,
		     const char *message, void *cb_data)
{
	struct cmd_reflog_expire_cb *cb = cb_data;
	if (!cb->expire_total || timestamp < cb->expire_total)
		cb->recno++;
	return 0;
}
 
int reflog_delete(const char *rev, enum expire_reflog_flags flags, int verbose)
{
	struct cmd_reflog_expire_cb cmd = { 0 };
	int status = 0;
	reflog_expiry_should_prune_fn *should_prune_fn = should_expire_reflog_ent;
	const char *spec = strstr(rev, "@{");
	char *ep, *ref;
	int recno;
	struct expire_reflog_policy_cb cb = {
		.dry_run = !!(flags & EXPIRE_REFLOGS_DRY_RUN),
	};
 
	if (verbose)
		should_prune_fn = should_expire_reflog_ent_verbose;
 
	if (!spec)
		return error(_("not a reflog: %s"), rev);
 
	if (!dwim_log(rev, spec - rev, NULL, &ref)) {
		status |= error(_("no reflog for '%s'"), rev);
		goto cleanup;
	}
 
	recno = strtoul(spec + 2, &ep, 10);
	if (*ep == '}') {
		cmd.recno = -recno;
		for_each_reflog_ent(ref, count_reflog_ent, &cmd);
	} else {
		cmd.expire_total = approxidate(spec + 2);
		for_each_reflog_ent(ref, count_reflog_ent, &cmd);
		cmd.expire_total = 0;
	}
 
	cb.cmd = cmd;
	status |= reflog_expire(ref, flags,
				reflog_expiry_prepare,
				should_prune_fn,
				reflog_expiry_cleanup,
				&cb);
 
 cleanup:
	free(ref);
	return status;
}