1#include "builtin.h"
2#include "lockfile.h"
3#include "commit.h"
4#include "refs.h"
5#include "dir.h"
6#include "tree-walk.h"
7#include "diff.h"
8#include "revision.h"
9#include "reachable.h"
10
11/* NEEDSWORK: switch to using parse_options */
12static const char reflog_expire_usage[] =
13"git reflog expire [--expire=<time>] [--expire-unreachable=<time>] [--rewrite] [--updateref] [--stale-fix] [--dry-run | -n] [--verbose] [--all] <refs>...";
14static const char reflog_delete_usage[] =
15"git reflog delete [--rewrite] [--updateref] [--dry-run | -n] [--verbose] <refs>...";
16
17static unsigned long default_reflog_expire;
18static unsigned long default_reflog_expire_unreachable;
19
20struct cmd_reflog_expire_cb {
21 struct rev_info revs;
22 int stalefix;
23 unsigned long expire_total;
24 unsigned long expire_unreachable;
25 int recno;
26};
27
28struct expire_reflog_policy_cb {
29 enum {
30 UE_NORMAL,
31 UE_ALWAYS,
32 UE_HEAD
33 } unreachable_expire_kind;
34 struct commit_list *mark_list;
35 unsigned long mark_limit;
36 struct cmd_reflog_expire_cb cmd;
37 struct commit *tip_commit;
38 struct commit_list *tips;
39};
40
41struct collected_reflog {
42 unsigned char sha1[20];
43 char reflog[FLEX_ARRAY];
44};
45
46struct collect_reflog_cb {
47 struct collected_reflog **e;
48 int alloc;
49 int nr;
50};
51
52#define INCOMPLETE (1u<<10)
53#define STUDYING (1u<<11)
54#define REACHABLE (1u<<12)
55
56static int tree_is_complete(const unsigned char *sha1)
57{
58 struct tree_desc desc;
59 struct name_entry entry;
60 int complete;
61 struct tree *tree;
62
63 tree = lookup_tree(sha1);
64 if (!tree)
65 return 0;
66 if (tree->object.flags & SEEN)
67 return 1;
68 if (tree->object.flags & INCOMPLETE)
69 return 0;
70
71 if (!tree->buffer) {
72 enum object_type type;
73 unsigned long size;
74 void *data = read_sha1_file(sha1, &type, &size);
75 if (!data) {
76 tree->object.flags |= INCOMPLETE;
77 return 0;
78 }
79 tree->buffer = data;
80 tree->size = size;
81 }
82 init_tree_desc(&desc, tree->buffer, tree->size);
83 complete = 1;
84 while (tree_entry(&desc, &entry)) {
85 if (!has_sha1_file(entry.sha1) ||
86 (S_ISDIR(entry.mode) && !tree_is_complete(entry.sha1))) {
87 tree->object.flags |= INCOMPLETE;
88 complete = 0;
89 }
90 }
91 free_tree_buffer(tree);
92
93 if (complete)
94 tree->object.flags |= SEEN;
95 return complete;
96}
97
98static int commit_is_complete(struct commit *commit)
99{
100 struct object_array study;
101 struct object_array found;
102 int is_incomplete = 0;
103 int i;
104
105 /* early return */
106 if (commit->object.flags & SEEN)
107 return 1;
108 if (commit->object.flags & INCOMPLETE)
109 return 0;
110 /*
111 * Find all commits that are reachable and are not marked as
112 * SEEN. Then make sure the trees and blobs contained are
113 * complete. After that, mark these commits also as SEEN.
114 * If some of the objects that are needed to complete this
115 * commit are missing, mark this commit as INCOMPLETE.
116 */
117 memset(&study, 0, sizeof(study));
118 memset(&found, 0, sizeof(found));
119 add_object_array(&commit->object, NULL, &study);
120 add_object_array(&commit->object, NULL, &found);
121 commit->object.flags |= STUDYING;
122 while (study.nr) {
123 struct commit *c;
124 struct commit_list *parent;
125
126 c = (struct commit *)study.objects[--study.nr].item;
127 if (!c->object.parsed && !parse_object(c->object.sha1))
128 c->object.flags |= INCOMPLETE;
129
130 if (c->object.flags & INCOMPLETE) {
131 is_incomplete = 1;
132 break;
133 }
134 else if (c->object.flags & SEEN)
135 continue;
136 for (parent = c->parents; parent; parent = parent->next) {
137 struct commit *p = parent->item;
138 if (p->object.flags & STUDYING)
139 continue;
140 p->object.flags |= STUDYING;
141 add_object_array(&p->object, NULL, &study);
142 add_object_array(&p->object, NULL, &found);
143 }
144 }
145 if (!is_incomplete) {
146 /*
147 * make sure all commits in "found" array have all the
148 * necessary objects.
149 */
150 for (i = 0; i < found.nr; i++) {
151 struct commit *c =
152 (struct commit *)found.objects[i].item;
153 if (!tree_is_complete(c->tree->object.sha1)) {
154 is_incomplete = 1;
155 c->object.flags |= INCOMPLETE;
156 }
157 }
158 if (!is_incomplete) {
159 /* mark all found commits as complete, iow SEEN */
160 for (i = 0; i < found.nr; i++)
161 found.objects[i].item->flags |= SEEN;
162 }
163 }
164 /* clear flags from the objects we traversed */
165 for (i = 0; i < found.nr; i++)
166 found.objects[i].item->flags &= ~STUDYING;
167 if (is_incomplete)
168 commit->object.flags |= INCOMPLETE;
169 else {
170 /*
171 * If we come here, we have (1) traversed the ancestry chain
172 * from the "commit" until we reach SEEN commits (which are
173 * known to be complete), and (2) made sure that the commits
174 * encountered during the above traversal refer to trees that
175 * are complete. Which means that we know *all* the commits
176 * we have seen during this process are complete.
177 */
178 for (i = 0; i < found.nr; i++)
179 found.objects[i].item->flags |= SEEN;
180 }
181 /* free object arrays */
182 free(study.objects);
183 free(found.objects);
184 return !is_incomplete;
185}
186
187static int keep_entry(struct commit **it, unsigned char *sha1)
188{
189 struct commit *commit;
190
191 if (is_null_sha1(sha1))
192 return 1;
193 commit = lookup_commit_reference_gently(sha1, 1);
194 if (!commit)
195 return 0;
196
197 /*
198 * Make sure everything in this commit exists.
199 *
200 * We have walked all the objects reachable from the refs
201 * and cache earlier. The commits reachable by this commit
202 * must meet SEEN commits -- and then we should mark them as
203 * SEEN as well.
204 */
205 if (!commit_is_complete(commit))
206 return 0;
207 *it = commit;
208 return 1;
209}
210
211/*
212 * Starting from commits in the cb->mark_list, mark commits that are
213 * reachable from them. Stop the traversal at commits older than
214 * the expire_limit and queue them back, so that the caller can call
215 * us again to restart the traversal with longer expire_limit.
216 */
217static void mark_reachable(struct expire_reflog_policy_cb *cb)
218{
219 struct commit *commit;
220 struct commit_list *pending;
221 unsigned long expire_limit = cb->mark_limit;
222 struct commit_list *leftover = NULL;
223
224 for (pending = cb->mark_list; pending; pending = pending->next)
225 pending->item->object.flags &= ~REACHABLE;
226
227 pending = cb->mark_list;
228 while (pending) {
229 struct commit_list *entry = pending;
230 struct commit_list *parent;
231 pending = entry->next;
232 commit = entry->item;
233 free(entry);
234 if (commit->object.flags & REACHABLE)
235 continue;
236 if (parse_commit(commit))
237 continue;
238 commit->object.flags |= REACHABLE;
239 if (commit->date < expire_limit) {
240 commit_list_insert(commit, &leftover);
241 continue;
242 }
243 commit->object.flags |= REACHABLE;
244 parent = commit->parents;
245 while (parent) {
246 commit = parent->item;
247 parent = parent->next;
248 if (commit->object.flags & REACHABLE)
249 continue;
250 commit_list_insert(commit, &pending);
251 }
252 }
253 cb->mark_list = leftover;
254}
255
256static int unreachable(struct expire_reflog_policy_cb *cb, struct commit *commit, unsigned char *sha1)
257{
258 /*
259 * We may or may not have the commit yet - if not, look it
260 * up using the supplied sha1.
261 */
262 if (!commit) {
263 if (is_null_sha1(sha1))
264 return 0;
265
266 commit = lookup_commit_reference_gently(sha1, 1);
267
268 /* Not a commit -- keep it */
269 if (!commit)
270 return 0;
271 }
272
273 /* Reachable from the current ref? Don't prune. */
274 if (commit->object.flags & REACHABLE)
275 return 0;
276
277 if (cb->mark_list && cb->mark_limit) {
278 cb->mark_limit = 0; /* dig down to the root */
279 mark_reachable(cb);
280 }
281
282 return !(commit->object.flags & REACHABLE);
283}
284
285/*
286 * Return true iff the specified reflog entry should be expired.
287 */
288static int should_expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
289 const char *email, unsigned long timestamp, int tz,
290 const char *message, void *cb_data)
291{
292 struct expire_reflog_policy_cb *cb = cb_data;
293 struct commit *old, *new;
294
295 if (timestamp < cb->cmd.expire_total)
296 return 1;
297
298 old = new = NULL;
299 if (cb->cmd.stalefix &&
300 (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
301 return 1;
302
303 if (timestamp < cb->cmd.expire_unreachable) {
304 if (cb->unreachable_expire_kind == UE_ALWAYS)
305 return 1;
306 if (unreachable(cb, old, osha1) || unreachable(cb, new, nsha1))
307 return 1;
308 }
309
310 if (cb->cmd.recno && --(cb->cmd.recno) == 0)
311 return 1;
312
313 return 0;
314}
315
316static int push_tip_to_list(const char *refname, const unsigned char *sha1,
317 int flags, void *cb_data)
318{
319 struct commit_list **list = cb_data;
320 struct commit *tip_commit;
321 if (flags & REF_ISSYMREF)
322 return 0;
323 tip_commit = lookup_commit_reference_gently(sha1, 1);
324 if (!tip_commit)
325 return 0;
326 commit_list_insert(tip_commit, list);
327 return 0;
328}
329
330static void reflog_expiry_prepare(const char *refname,
331 const unsigned char *sha1,
332 void *cb_data)
333{
334 struct expire_reflog_policy_cb *cb = cb_data;
335
336 if (!cb->cmd.expire_unreachable || !strcmp(refname, "HEAD")) {
337 cb->tip_commit = NULL;
338 cb->unreachable_expire_kind = UE_HEAD;
339 } else {
340 cb->tip_commit = lookup_commit_reference_gently(sha1, 1);
341 if (!cb->tip_commit)
342 cb->unreachable_expire_kind = UE_ALWAYS;
343 else
344 cb->unreachable_expire_kind = UE_NORMAL;
345 }
346
347 if (cb->cmd.expire_unreachable <= cb->cmd.expire_total)
348 cb->unreachable_expire_kind = UE_ALWAYS;
349
350 cb->mark_list = NULL;
351 cb->tips = NULL;
352 if (cb->unreachable_expire_kind != UE_ALWAYS) {
353 if (cb->unreachable_expire_kind == UE_HEAD) {
354 struct commit_list *elem;
355 for_each_ref(push_tip_to_list, &cb->tips);
356 for (elem = cb->tips; elem; elem = elem->next)
357 commit_list_insert(elem->item, &cb->mark_list);
358 } else {
359 commit_list_insert(cb->tip_commit, &cb->mark_list);
360 }
361 cb->mark_limit = cb->cmd.expire_total;
362 mark_reachable(cb);
363 }
364}
365
366static void reflog_expiry_cleanup(void *cb_data)
367{
368 struct expire_reflog_policy_cb *cb = cb_data;
369
370 if (cb->unreachable_expire_kind != UE_ALWAYS) {
371 if (cb->unreachable_expire_kind == UE_HEAD) {
372 struct commit_list *elem;
373 for (elem = cb->tips; elem; elem = elem->next)
374 clear_commit_marks(elem->item, REACHABLE);
375 free_commit_list(cb->tips);
376 } else {
377 clear_commit_marks(cb->tip_commit, REACHABLE);
378 }
379 }
380}
381
382static int collect_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
383{
384 struct collected_reflog *e;
385 struct collect_reflog_cb *cb = cb_data;
386 size_t namelen = strlen(ref);
387
388 e = xmalloc(sizeof(*e) + namelen + 1);
389 hashcpy(e->sha1, sha1);
390 memcpy(e->reflog, ref, namelen + 1);
391 ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
392 cb->e[cb->nr++] = e;
393 return 0;
394}
395
396static struct reflog_expire_cfg {
397 struct reflog_expire_cfg *next;
398 unsigned long expire_total;
399 unsigned long expire_unreachable;
400 size_t len;
401 char pattern[FLEX_ARRAY];
402} *reflog_expire_cfg, **reflog_expire_cfg_tail;
403
404static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
405{
406 struct reflog_expire_cfg *ent;
407
408 if (!reflog_expire_cfg_tail)
409 reflog_expire_cfg_tail = &reflog_expire_cfg;
410
411 for (ent = reflog_expire_cfg; ent; ent = ent->next)
412 if (ent->len == len &&
413 !memcmp(ent->pattern, pattern, len))
414 return ent;
415
416 ent = xcalloc(1, (sizeof(*ent) + len));
417 memcpy(ent->pattern, pattern, len);
418 ent->len = len;
419 *reflog_expire_cfg_tail = ent;
420 reflog_expire_cfg_tail = &(ent->next);
421 return ent;
422}
423
424static int parse_expire_cfg_value(const char *var, const char *value, unsigned long *expire)
425{
426 if (!value)
427 return config_error_nonbool(var);
428 if (parse_expiry_date(value, expire))
429 return error(_("%s' for '%s' is not a valid timestamp"),
430 value, var);
431 return 0;
432}
433
434/* expiry timer slot */
435#define EXPIRE_TOTAL 01
436#define EXPIRE_UNREACH 02
437
438static int reflog_expire_config(const char *var, const char *value, void *cb)
439{
440 const char *pattern, *key;
441 int pattern_len;
442 unsigned long expire;
443 int slot;
444 struct reflog_expire_cfg *ent;
445
446 if (parse_config_key(var, "gc", &pattern, &pattern_len, &key) < 0)
447 return git_default_config(var, value, cb);
448
449 if (!strcmp(key, "reflogexpire")) {
450 slot = EXPIRE_TOTAL;
451 if (parse_expire_cfg_value(var, value, &expire))
452 return -1;
453 } else if (!strcmp(key, "reflogexpireunreachable")) {
454 slot = EXPIRE_UNREACH;
455 if (parse_expire_cfg_value(var, value, &expire))
456 return -1;
457 } else
458 return git_default_config(var, value, cb);
459
460 if (!pattern) {
461 switch (slot) {
462 case EXPIRE_TOTAL:
463 default_reflog_expire = expire;
464 break;
465 case EXPIRE_UNREACH:
466 default_reflog_expire_unreachable = expire;
467 break;
468 }
469 return 0;
470 }
471
472 ent = find_cfg_ent(pattern, pattern_len);
473 if (!ent)
474 return -1;
475 switch (slot) {
476 case EXPIRE_TOTAL:
477 ent->expire_total = expire;
478 break;
479 case EXPIRE_UNREACH:
480 ent->expire_unreachable = expire;
481 break;
482 }
483 return 0;
484}
485
486static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
487{
488 struct reflog_expire_cfg *ent;
489
490 if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
491 return; /* both given explicitly -- nothing to tweak */
492
493 for (ent = reflog_expire_cfg; ent; ent = ent->next) {
494 if (!wildmatch(ent->pattern, ref, 0, NULL)) {
495 if (!(slot & EXPIRE_TOTAL))
496 cb->expire_total = ent->expire_total;
497 if (!(slot & EXPIRE_UNREACH))
498 cb->expire_unreachable = ent->expire_unreachable;
499 return;
500 }
501 }
502
503 /*
504 * If unconfigured, make stash never expire
505 */
506 if (!strcmp(ref, "refs/stash")) {
507 if (!(slot & EXPIRE_TOTAL))
508 cb->expire_total = 0;
509 if (!(slot & EXPIRE_UNREACH))
510 cb->expire_unreachable = 0;
511 return;
512 }
513
514 /* Nothing matched -- use the default value */
515 if (!(slot & EXPIRE_TOTAL))
516 cb->expire_total = default_reflog_expire;
517 if (!(slot & EXPIRE_UNREACH))
518 cb->expire_unreachable = default_reflog_expire_unreachable;
519}
520
521static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
522{
523 struct expire_reflog_policy_cb cb;
524 unsigned long now = time(NULL);
525 int i, status, do_all;
526 int explicit_expiry = 0;
527 unsigned int flags = 0;
528
529 default_reflog_expire_unreachable = now - 30 * 24 * 3600;
530 default_reflog_expire = now - 90 * 24 * 3600;
531 git_config(reflog_expire_config, NULL);
532
533 save_commit_buffer = 0;
534 do_all = status = 0;
535 memset(&cb, 0, sizeof(cb));
536
537 cb.cmd.expire_total = default_reflog_expire;
538 cb.cmd.expire_unreachable = default_reflog_expire_unreachable;
539
540 for (i = 1; i < argc; i++) {
541 const char *arg = argv[i];
542 if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
543 flags |= EXPIRE_REFLOGS_DRY_RUN;
544 else if (starts_with(arg, "--expire=")) {
545 if (parse_expiry_date(arg + 9, &cb.cmd.expire_total))
546 die(_("'%s' is not a valid timestamp"), arg);
547 explicit_expiry |= EXPIRE_TOTAL;
548 }
549 else if (starts_with(arg, "--expire-unreachable=")) {
550 if (parse_expiry_date(arg + 21, &cb.cmd.expire_unreachable))
551 die(_("'%s' is not a valid timestamp"), arg);
552 explicit_expiry |= EXPIRE_UNREACH;
553 }
554 else if (!strcmp(arg, "--stale-fix"))
555 cb.cmd.stalefix = 1;
556 else if (!strcmp(arg, "--rewrite"))
557 flags |= EXPIRE_REFLOGS_REWRITE;
558 else if (!strcmp(arg, "--updateref"))
559 flags |= EXPIRE_REFLOGS_UPDATE_REF;
560 else if (!strcmp(arg, "--all"))
561 do_all = 1;
562 else if (!strcmp(arg, "--verbose"))
563 flags |= EXPIRE_REFLOGS_VERBOSE;
564 else if (!strcmp(arg, "--")) {
565 i++;
566 break;
567 }
568 else if (arg[0] == '-')
569 usage(reflog_expire_usage);
570 else
571 break;
572 }
573
574 /*
575 * We can trust the commits and objects reachable from refs
576 * even in older repository. We cannot trust what's reachable
577 * from reflog if the repository was pruned with older git.
578 */
579 if (cb.cmd.stalefix) {
580 init_revisions(&cb.cmd.revs, prefix);
581 if (flags & EXPIRE_REFLOGS_VERBOSE)
582 printf("Marking reachable objects...");
583 mark_reachable_objects(&cb.cmd.revs, 0, 0, NULL);
584 if (flags & EXPIRE_REFLOGS_VERBOSE)
585 putchar('\n');
586 }
587
588 if (do_all) {
589 struct collect_reflog_cb collected;
590 int i;
591
592 memset(&collected, 0, sizeof(collected));
593 for_each_reflog(collect_reflog, &collected);
594 for (i = 0; i < collected.nr; i++) {
595 struct collected_reflog *e = collected.e[i];
596 set_reflog_expiry_param(&cb.cmd, explicit_expiry, e->reflog);
597 status |= reflog_expire(e->reflog, e->sha1, flags,
598 reflog_expiry_prepare,
599 should_expire_reflog_ent,
600 reflog_expiry_cleanup,
601 &cb);
602 free(e);
603 }
604 free(collected.e);
605 }
606
607 for (; i < argc; i++) {
608 char *ref;
609 unsigned char sha1[20];
610 if (!dwim_log(argv[i], strlen(argv[i]), sha1, &ref)) {
611 status |= error("%s points nowhere!", argv[i]);
612 continue;
613 }
614 set_reflog_expiry_param(&cb.cmd, explicit_expiry, ref);
615 status |= reflog_expire(ref, sha1, flags,
616 reflog_expiry_prepare,
617 should_expire_reflog_ent,
618 reflog_expiry_cleanup,
619 &cb);
620 }
621 return status;
622}
623
624static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
625 const char *email, unsigned long timestamp, int tz,
626 const char *message, void *cb_data)
627{
628 struct expire_reflog_policy_cb *cb = cb_data;
629 if (!cb->cmd.expire_total || timestamp < cb->cmd.expire_total)
630 cb->cmd.recno++;
631 return 0;
632}
633
634static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
635{
636 struct expire_reflog_policy_cb cb;
637 int i, status = 0;
638 unsigned int flags = 0;
639
640 memset(&cb, 0, sizeof(cb));
641
642 for (i = 1; i < argc; i++) {
643 const char *arg = argv[i];
644 if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
645 flags |= EXPIRE_REFLOGS_DRY_RUN;
646 else if (!strcmp(arg, "--rewrite"))
647 flags |= EXPIRE_REFLOGS_REWRITE;
648 else if (!strcmp(arg, "--updateref"))
649 flags |= EXPIRE_REFLOGS_UPDATE_REF;
650 else if (!strcmp(arg, "--verbose"))
651 flags |= EXPIRE_REFLOGS_VERBOSE;
652 else if (!strcmp(arg, "--")) {
653 i++;
654 break;
655 }
656 else if (arg[0] == '-')
657 usage(reflog_delete_usage);
658 else
659 break;
660 }
661
662 if (argc - i < 1)
663 return error("Nothing to delete?");
664
665 for ( ; i < argc; i++) {
666 const char *spec = strstr(argv[i], "@{");
667 unsigned char sha1[20];
668 char *ep, *ref;
669 int recno;
670
671 if (!spec) {
672 status |= error("Not a reflog: %s", argv[i]);
673 continue;
674 }
675
676 if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
677 status |= error("no reflog for '%s'", argv[i]);
678 continue;
679 }
680
681 recno = strtoul(spec + 2, &ep, 10);
682 if (*ep == '}') {
683 cb.cmd.recno = -recno;
684 for_each_reflog_ent(ref, count_reflog_ent, &cb);
685 } else {
686 cb.cmd.expire_total = approxidate(spec + 2);
687 for_each_reflog_ent(ref, count_reflog_ent, &cb);
688 cb.cmd.expire_total = 0;
689 }
690
691 status |= reflog_expire(ref, sha1, flags,
692 reflog_expiry_prepare,
693 should_expire_reflog_ent,
694 reflog_expiry_cleanup,
695 &cb);
696 free(ref);
697 }
698 return status;
699}
700
701/*
702 * main "reflog"
703 */
704
705static const char reflog_usage[] =
706"git reflog [ show | expire | delete ]";
707
708int cmd_reflog(int argc, const char **argv, const char *prefix)
709{
710 if (argc > 1 && !strcmp(argv[1], "-h"))
711 usage(reflog_usage);
712
713 /* With no command, we default to showing it. */
714 if (argc < 2 || *argv[1] == '-')
715 return cmd_log_reflog(argc, argv, prefix);
716
717 if (!strcmp(argv[1], "show"))
718 return cmd_log_reflog(argc - 1, argv + 1, prefix);
719
720 if (!strcmp(argv[1], "expire"))
721 return cmd_reflog_expire(argc - 1, argv + 1, prefix);
722
723 if (!strcmp(argv[1], "delete"))
724 return cmd_reflog_delete(argc - 1, argv + 1, prefix);
725
726 return cmd_log_reflog(argc, argv, prefix);
727}