1#include "cache.h"
2#include "builtin.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/*
12 * reflog expire
13 */
14
15static const char reflog_expire_usage[] =
16"git reflog (show|expire) [--verbose] [--dry-run] [--stale-fix] [--expire=<time>] [--expire-unreachable=<time>] [--all] <refs>...";
17static const char reflog_delete_usage[] =
18"git reflog delete [--verbose] [--dry-run] [--rewrite] [--updateref] <refs>...";
19
20static unsigned long default_reflog_expire;
21static unsigned long default_reflog_expire_unreachable;
22
23struct cmd_reflog_expire_cb {
24 struct rev_info revs;
25 int dry_run;
26 int stalefix;
27 int rewrite;
28 int updateref;
29 int verbose;
30 unsigned long expire_total;
31 unsigned long expire_unreachable;
32 int recno;
33};
34
35struct expire_reflog_cb {
36 FILE *newlog;
37 const char *ref;
38 struct commit *ref_commit;
39 struct cmd_reflog_expire_cb *cmd;
40 unsigned char last_kept_sha1[20];
41};
42
43struct collected_reflog {
44 unsigned char sha1[20];
45 char reflog[FLEX_ARRAY];
46};
47struct collect_reflog_cb {
48 struct collected_reflog **e;
49 int alloc;
50 int nr;
51};
52
53#define INCOMPLETE (1u<<10)
54#define STUDYING (1u<<11)
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);
92 tree->buffer = NULL;
93
94 if (complete)
95 tree->object.flags |= SEEN;
96 return complete;
97}
98
99static int commit_is_complete(struct commit *commit)
100{
101 struct object_array study;
102 struct object_array found;
103 int is_incomplete = 0;
104 int i;
105
106 /* early return */
107 if (commit->object.flags & SEEN)
108 return 1;
109 if (commit->object.flags & INCOMPLETE)
110 return 0;
111 /*
112 * Find all commits that are reachable and are not marked as
113 * SEEN. Then make sure the trees and blobs contained are
114 * complete. After that, mark these commits also as SEEN.
115 * If some of the objects that are needed to complete this
116 * commit are missing, mark this commit as INCOMPLETE.
117 */
118 memset(&study, 0, sizeof(study));
119 memset(&found, 0, sizeof(found));
120 add_object_array(&commit->object, NULL, &study);
121 add_object_array(&commit->object, NULL, &found);
122 commit->object.flags |= STUDYING;
123 while (study.nr) {
124 struct commit *c;
125 struct commit_list *parent;
126
127 c = (struct commit *)study.objects[--study.nr].item;
128 if (!c->object.parsed && !parse_object(c->object.sha1))
129 c->object.flags |= INCOMPLETE;
130
131 if (c->object.flags & INCOMPLETE) {
132 is_incomplete = 1;
133 break;
134 }
135 else if (c->object.flags & SEEN)
136 continue;
137 for (parent = c->parents; parent; parent = parent->next) {
138 struct commit *p = parent->item;
139 if (p->object.flags & STUDYING)
140 continue;
141 p->object.flags |= STUDYING;
142 add_object_array(&p->object, NULL, &study);
143 add_object_array(&p->object, NULL, &found);
144 }
145 }
146 if (!is_incomplete) {
147 /*
148 * make sure all commits in "found" array have all the
149 * necessary objects.
150 */
151 for (i = 0; i < found.nr; i++) {
152 struct commit *c =
153 (struct commit *)found.objects[i].item;
154 if (!tree_is_complete(c->tree->object.sha1)) {
155 is_incomplete = 1;
156 c->object.flags |= INCOMPLETE;
157 }
158 }
159 if (!is_incomplete) {
160 /* mark all found commits as complete, iow SEEN */
161 for (i = 0; i < found.nr; i++)
162 found.objects[i].item->flags |= SEEN;
163 }
164 }
165 /* clear flags from the objects we traversed */
166 for (i = 0; i < found.nr; i++)
167 found.objects[i].item->flags &= ~STUDYING;
168 if (is_incomplete)
169 commit->object.flags |= INCOMPLETE;
170 else {
171 /*
172 * If we come here, we have (1) traversed the ancestry chain
173 * from the "commit" until we reach SEEN commits (which are
174 * known to be complete), and (2) made sure that the commits
175 * encountered during the above traversal refer to trees that
176 * are complete. Which means that we know *all* the commits
177 * we have seen during this process are complete.
178 */
179 for (i = 0; i < found.nr; i++)
180 found.objects[i].item->flags |= SEEN;
181 }
182 /* free object arrays */
183 free(study.objects);
184 free(found.objects);
185 return !is_incomplete;
186}
187
188static int keep_entry(struct commit **it, unsigned char *sha1)
189{
190 struct commit *commit;
191
192 if (is_null_sha1(sha1))
193 return 1;
194 commit = lookup_commit_reference_gently(sha1, 1);
195 if (!commit)
196 return 0;
197
198 /*
199 * Make sure everything in this commit exists.
200 *
201 * We have walked all the objects reachable from the refs
202 * and cache earlier. The commits reachable by this commit
203 * must meet SEEN commits -- and then we should mark them as
204 * SEEN as well.
205 */
206 if (!commit_is_complete(commit))
207 return 0;
208 *it = commit;
209 return 1;
210}
211
212static int expire_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
213 const char *email, unsigned long timestamp, int tz,
214 const char *message, void *cb_data)
215{
216 struct expire_reflog_cb *cb = cb_data;
217 struct commit *old, *new;
218
219 if (timestamp < cb->cmd->expire_total)
220 goto prune;
221
222 if (cb->cmd->rewrite)
223 osha1 = cb->last_kept_sha1;
224
225 old = new = NULL;
226 if (cb->cmd->stalefix &&
227 (!keep_entry(&old, osha1) || !keep_entry(&new, nsha1)))
228 goto prune;
229
230 if (timestamp < cb->cmd->expire_unreachable) {
231 if (!cb->ref_commit)
232 goto prune;
233 if (!old && !is_null_sha1(osha1))
234 old = lookup_commit_reference_gently(osha1, 1);
235 if (!new && !is_null_sha1(nsha1))
236 new = lookup_commit_reference_gently(nsha1, 1);
237 if ((old && !in_merge_bases(old, &cb->ref_commit, 1)) ||
238 (new && !in_merge_bases(new, &cb->ref_commit, 1)))
239 goto prune;
240 }
241
242 if (cb->cmd->recno && --(cb->cmd->recno) == 0)
243 goto prune;
244
245 if (cb->newlog) {
246 char sign = (tz < 0) ? '-' : '+';
247 int zone = (tz < 0) ? (-tz) : tz;
248 fprintf(cb->newlog, "%s %s %s %lu %c%04d\t%s",
249 sha1_to_hex(osha1), sha1_to_hex(nsha1),
250 email, timestamp, sign, zone,
251 message);
252 hashcpy(cb->last_kept_sha1, nsha1);
253 }
254 if (cb->cmd->verbose)
255 printf("keep %s", message);
256 return 0;
257 prune:
258 if (!cb->newlog || cb->cmd->verbose)
259 printf("%sprune %s", cb->newlog ? "" : "would ", message);
260 return 0;
261}
262
263static int expire_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
264{
265 struct cmd_reflog_expire_cb *cmd = cb_data;
266 struct expire_reflog_cb cb;
267 struct ref_lock *lock;
268 char *log_file, *newlog_path = NULL;
269 int status = 0;
270
271 memset(&cb, 0, sizeof(cb));
272
273 /*
274 * we take the lock for the ref itself to prevent it from
275 * getting updated.
276 */
277 lock = lock_any_ref_for_update(ref, sha1, 0);
278 if (!lock)
279 return error("cannot lock ref '%s'", ref);
280 log_file = xstrdup(git_path("logs/%s", ref));
281 if (!file_exists(log_file))
282 goto finish;
283 if (!cmd->dry_run) {
284 newlog_path = xstrdup(git_path("logs/%s.lock", ref));
285 cb.newlog = fopen(newlog_path, "w");
286 }
287
288 cb.ref_commit = lookup_commit_reference_gently(sha1, 1);
289 cb.ref = ref;
290 cb.cmd = cmd;
291 for_each_reflog_ent(ref, expire_reflog_ent, &cb);
292 finish:
293 if (cb.newlog) {
294 if (fclose(cb.newlog)) {
295 status |= error("%s: %s", strerror(errno),
296 newlog_path);
297 unlink(newlog_path);
298 } else if (cmd->updateref &&
299 (write_in_full(lock->lock_fd,
300 sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
301 write_in_full(lock->lock_fd, "\n", 1) != 1 ||
302 close_ref(lock) < 0)) {
303 status |= error("Couldn't write %s",
304 lock->lk->filename);
305 unlink(newlog_path);
306 } else if (rename(newlog_path, log_file)) {
307 status |= error("cannot rename %s to %s",
308 newlog_path, log_file);
309 unlink(newlog_path);
310 } else if (cmd->updateref && commit_ref(lock)) {
311 status |= error("Couldn't set %s", lock->ref_name);
312 } else {
313 adjust_shared_perm(log_file);
314 }
315 }
316 free(newlog_path);
317 free(log_file);
318 unlock_ref(lock);
319 return status;
320}
321
322static int collect_reflog(const char *ref, const unsigned char *sha1, int unused, void *cb_data)
323{
324 struct collected_reflog *e;
325 struct collect_reflog_cb *cb = cb_data;
326 size_t namelen = strlen(ref);
327
328 e = xmalloc(sizeof(*e) + namelen + 1);
329 hashcpy(e->sha1, sha1);
330 memcpy(e->reflog, ref, namelen + 1);
331 ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
332 cb->e[cb->nr++] = e;
333 return 0;
334}
335
336static struct reflog_expire_cfg {
337 struct reflog_expire_cfg *next;
338 unsigned long expire_total;
339 unsigned long expire_unreachable;
340 size_t len;
341 char pattern[FLEX_ARRAY];
342} *reflog_expire_cfg, **reflog_expire_cfg_tail;
343
344static struct reflog_expire_cfg *find_cfg_ent(const char *pattern, size_t len)
345{
346 struct reflog_expire_cfg *ent;
347
348 if (!reflog_expire_cfg_tail)
349 reflog_expire_cfg_tail = &reflog_expire_cfg;
350
351 for (ent = reflog_expire_cfg; ent; ent = ent->next)
352 if (ent->len == len &&
353 !memcmp(ent->pattern, pattern, len))
354 return ent;
355
356 ent = xcalloc(1, (sizeof(*ent) + len));
357 memcpy(ent->pattern, pattern, len);
358 ent->len = len;
359 *reflog_expire_cfg_tail = ent;
360 reflog_expire_cfg_tail = &(ent->next);
361 return ent;
362}
363
364static int parse_expire_cfg_value(const char *var, const char *value, unsigned long *expire)
365{
366 if (!value)
367 return config_error_nonbool(var);
368 if (!strcmp(value, "never") || !strcmp(value, "false")) {
369 *expire = 0;
370 return 0;
371 }
372 *expire = approxidate(value);
373 return 0;
374}
375
376/* expiry timer slot */
377#define EXPIRE_TOTAL 01
378#define EXPIRE_UNREACH 02
379
380static int reflog_expire_config(const char *var, const char *value, void *cb)
381{
382 const char *lastdot = strrchr(var, '.');
383 unsigned long expire;
384 int slot;
385 struct reflog_expire_cfg *ent;
386
387 if (!lastdot || prefixcmp(var, "gc."))
388 return git_default_config(var, value, cb);
389
390 if (!strcmp(lastdot, ".reflogexpire")) {
391 slot = EXPIRE_TOTAL;
392 if (parse_expire_cfg_value(var, value, &expire))
393 return -1;
394 } else if (!strcmp(lastdot, ".reflogexpireunreachable")) {
395 slot = EXPIRE_UNREACH;
396 if (parse_expire_cfg_value(var, value, &expire))
397 return -1;
398 } else
399 return git_default_config(var, value, cb);
400
401 if (lastdot == var + 2) {
402 switch (slot) {
403 case EXPIRE_TOTAL:
404 default_reflog_expire = expire;
405 break;
406 case EXPIRE_UNREACH:
407 default_reflog_expire_unreachable = expire;
408 break;
409 }
410 return 0;
411 }
412
413 ent = find_cfg_ent(var + 3, lastdot - (var+3));
414 if (!ent)
415 return -1;
416 switch (slot) {
417 case EXPIRE_TOTAL:
418 ent->expire_total = expire;
419 break;
420 case EXPIRE_UNREACH:
421 ent->expire_unreachable = expire;
422 break;
423 }
424 return 0;
425}
426
427static void set_reflog_expiry_param(struct cmd_reflog_expire_cb *cb, int slot, const char *ref)
428{
429 struct reflog_expire_cfg *ent;
430
431 if (slot == (EXPIRE_TOTAL|EXPIRE_UNREACH))
432 return; /* both given explicitly -- nothing to tweak */
433
434 for (ent = reflog_expire_cfg; ent; ent = ent->next) {
435 if (!fnmatch(ent->pattern, ref, 0)) {
436 if (!(slot & EXPIRE_TOTAL))
437 cb->expire_total = ent->expire_total;
438 if (!(slot & EXPIRE_UNREACH))
439 cb->expire_unreachable = ent->expire_unreachable;
440 return;
441 }
442 }
443
444 /*
445 * If unconfigured, make stash never expire
446 */
447 if (!strcmp(ref, "refs/stash")) {
448 if (!(slot & EXPIRE_TOTAL))
449 cb->expire_total = 0;
450 if (!(slot & EXPIRE_UNREACH))
451 cb->expire_unreachable = 0;
452 return;
453 }
454
455 /* Nothing matched -- use the default value */
456 if (!(slot & EXPIRE_TOTAL))
457 cb->expire_total = default_reflog_expire;
458 if (!(slot & EXPIRE_UNREACH))
459 cb->expire_unreachable = default_reflog_expire_unreachable;
460}
461
462static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
463{
464 struct cmd_reflog_expire_cb cb;
465 unsigned long now = time(NULL);
466 int i, status, do_all;
467 int explicit_expiry = 0;
468
469 git_config(reflog_expire_config, NULL);
470
471 save_commit_buffer = 0;
472 do_all = status = 0;
473 memset(&cb, 0, sizeof(cb));
474
475 if (!default_reflog_expire_unreachable)
476 default_reflog_expire_unreachable = now - 30 * 24 * 3600;
477 if (!default_reflog_expire)
478 default_reflog_expire = now - 90 * 24 * 3600;
479 cb.expire_total = default_reflog_expire;
480 cb.expire_unreachable = default_reflog_expire_unreachable;
481
482 for (i = 1; i < argc; i++) {
483 const char *arg = argv[i];
484 if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
485 cb.dry_run = 1;
486 else if (!prefixcmp(arg, "--expire=")) {
487 cb.expire_total = approxidate(arg + 9);
488 explicit_expiry |= EXPIRE_TOTAL;
489 }
490 else if (!prefixcmp(arg, "--expire-unreachable=")) {
491 cb.expire_unreachable = approxidate(arg + 21);
492 explicit_expiry |= EXPIRE_UNREACH;
493 }
494 else if (!strcmp(arg, "--stale-fix"))
495 cb.stalefix = 1;
496 else if (!strcmp(arg, "--rewrite"))
497 cb.rewrite = 1;
498 else if (!strcmp(arg, "--updateref"))
499 cb.updateref = 1;
500 else if (!strcmp(arg, "--all"))
501 do_all = 1;
502 else if (!strcmp(arg, "--verbose"))
503 cb.verbose = 1;
504 else if (!strcmp(arg, "--")) {
505 i++;
506 break;
507 }
508 else if (arg[0] == '-')
509 usage(reflog_expire_usage);
510 else
511 break;
512 }
513
514 /*
515 * We can trust the commits and objects reachable from refs
516 * even in older repository. We cannot trust what's reachable
517 * from reflog if the repository was pruned with older git.
518 */
519 if (cb.stalefix) {
520 init_revisions(&cb.revs, prefix);
521 if (cb.verbose)
522 printf("Marking reachable objects...");
523 mark_reachable_objects(&cb.revs, 0);
524 if (cb.verbose)
525 putchar('\n');
526 }
527
528 if (do_all) {
529 struct collect_reflog_cb collected;
530 int i;
531
532 memset(&collected, 0, sizeof(collected));
533 for_each_reflog(collect_reflog, &collected);
534 for (i = 0; i < collected.nr; i++) {
535 struct collected_reflog *e = collected.e[i];
536 set_reflog_expiry_param(&cb, explicit_expiry, e->reflog);
537 status |= expire_reflog(e->reflog, e->sha1, 0, &cb);
538 free(e);
539 }
540 free(collected.e);
541 }
542
543 while (i < argc) {
544 const char *ref = argv[i++];
545 unsigned char sha1[20];
546 if (!resolve_ref(ref, sha1, 1, NULL)) {
547 status |= error("%s points nowhere!", ref);
548 continue;
549 }
550 set_reflog_expiry_param(&cb, explicit_expiry, ref);
551 status |= expire_reflog(ref, sha1, 0, &cb);
552 }
553 return status;
554}
555
556static int count_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
557 const char *email, unsigned long timestamp, int tz,
558 const char *message, void *cb_data)
559{
560 struct cmd_reflog_expire_cb *cb = cb_data;
561 if (!cb->expire_total || timestamp < cb->expire_total)
562 cb->recno++;
563 return 0;
564}
565
566static int cmd_reflog_delete(int argc, const char **argv, const char *prefix)
567{
568 struct cmd_reflog_expire_cb cb;
569 int i, status = 0;
570
571 memset(&cb, 0, sizeof(cb));
572
573 for (i = 1; i < argc; i++) {
574 const char *arg = argv[i];
575 if (!strcmp(arg, "--dry-run") || !strcmp(arg, "-n"))
576 cb.dry_run = 1;
577 else if (!strcmp(arg, "--rewrite"))
578 cb.rewrite = 1;
579 else if (!strcmp(arg, "--updateref"))
580 cb.updateref = 1;
581 else if (!strcmp(arg, "--verbose"))
582 cb.verbose = 1;
583 else if (!strcmp(arg, "--")) {
584 i++;
585 break;
586 }
587 else if (arg[0] == '-')
588 usage(reflog_delete_usage);
589 else
590 break;
591 }
592
593 if (argc - i < 1)
594 return error("Nothing to delete?");
595
596 for ( ; i < argc; i++) {
597 const char *spec = strstr(argv[i], "@{");
598 unsigned char sha1[20];
599 char *ep, *ref;
600 int recno;
601
602 if (!spec) {
603 status |= error("Not a reflog: %s", argv[i]);
604 continue;
605 }
606
607 if (!dwim_log(argv[i], spec - argv[i], sha1, &ref)) {
608 status |= error("no reflog for '%s'", argv[i]);
609 continue;
610 }
611
612 recno = strtoul(spec + 2, &ep, 10);
613 if (*ep == '}') {
614 cb.recno = -recno;
615 for_each_reflog_ent(ref, count_reflog_ent, &cb);
616 } else {
617 cb.expire_total = approxidate(spec + 2);
618 for_each_reflog_ent(ref, count_reflog_ent, &cb);
619 cb.expire_total = 0;
620 }
621
622 status |= expire_reflog(ref, sha1, 0, &cb);
623 free(ref);
624 }
625 return status;
626}
627
628/*
629 * main "reflog"
630 */
631
632static const char reflog_usage[] =
633"git reflog (expire | ...)";
634
635int cmd_reflog(int argc, const char **argv, const char *prefix)
636{
637 /* With no command, we default to showing it. */
638 if (argc < 2 || *argv[1] == '-')
639 return cmd_log_reflog(argc, argv, prefix);
640
641 if (!strcmp(argv[1], "show"))
642 return cmd_log_reflog(argc - 1, argv + 1, prefix);
643
644 if (!strcmp(argv[1], "expire"))
645 return cmd_reflog_expire(argc - 1, argv + 1, prefix);
646
647 if (!strcmp(argv[1], "delete"))
648 return cmd_reflog_delete(argc - 1, argv + 1, prefix);
649
650 /* Not a recognized reflog command..*/
651 usage(reflog_usage);
652}