git-gc --prune is deprecated
[git] / builtin-fetch.c
1 /*
2  * "git fetch"
3  */
4 #include "cache.h"
5 #include "refs.h"
6 #include "commit.h"
7 #include "builtin.h"
8 #include "path-list.h"
9 #include "remote.h"
10 #include "transport.h"
11 #include "run-command.h"
12 #include "parse-options.h"
13
14 static const char * const builtin_fetch_usage[] = {
15         "git-fetch [options] [<repository> <refspec>...]",
16         NULL
17 };
18
19 enum {
20         TAGS_UNSET = 0,
21         TAGS_DEFAULT = 1,
22         TAGS_SET = 2
23 };
24
25 static int append, force, keep, update_head_ok, verbose, quiet;
26 static int tags = TAGS_DEFAULT;
27 static const char *depth;
28 static const char *upload_pack;
29 static struct strbuf default_rla = STRBUF_INIT;
30 static struct transport *transport;
31
32 static struct option builtin_fetch_options[] = {
33         OPT__QUIET(&quiet),
34         OPT__VERBOSE(&verbose),
35         OPT_BOOLEAN('a', "append", &append,
36                     "append to .git/FETCH_HEAD instead of overwriting"),
37         OPT_STRING(0, "upload-pack", &upload_pack, "PATH",
38                    "path to upload pack on remote end"),
39         OPT_BOOLEAN('f', "force", &force,
40                     "force overwrite of local branch"),
41         OPT_SET_INT('t', "tags", &tags,
42                     "fetch all tags and associated objects", TAGS_SET),
43         OPT_SET_INT('n', NULL, &tags,
44                     "do not fetch all tags (--no-tags)", TAGS_UNSET),
45         OPT_BOOLEAN('k', "keep", &keep, "keep downloaded pack"),
46         OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
47                     "allow updating of HEAD ref"),
48         OPT_STRING(0, "depth", &depth, "DEPTH",
49                    "deepen history of shallow clone"),
50         OPT_END()
51 };
52
53 static void unlock_pack(void)
54 {
55         if (transport)
56                 transport_unlock_pack(transport);
57 }
58
59 static void unlock_pack_on_signal(int signo)
60 {
61         unlock_pack();
62         signal(SIGINT, SIG_DFL);
63         raise(signo);
64 }
65
66 static void add_merge_config(struct ref **head,
67                            const struct ref *remote_refs,
68                            struct branch *branch,
69                            struct ref ***tail)
70 {
71         int i;
72
73         for (i = 0; i < branch->merge_nr; i++) {
74                 struct ref *rm, **old_tail = *tail;
75                 struct refspec refspec;
76
77                 for (rm = *head; rm; rm = rm->next) {
78                         if (branch_merge_matches(branch, i, rm->name)) {
79                                 rm->merge = 1;
80                                 break;
81                         }
82                 }
83                 if (rm)
84                         continue;
85
86                 /*
87                  * Not fetched to a tracking branch?  We need to fetch
88                  * it anyway to allow this branch's "branch.$name.merge"
89                  * to be honored by git-pull, but we do not have to
90                  * fail if branch.$name.merge is misconfigured to point
91                  * at a nonexisting branch.  If we were indeed called by
92                  * git-pull, it will notice the misconfiguration because
93                  * there is no entry in the resulting FETCH_HEAD marked
94                  * for merging.
95                  */
96                 refspec.src = branch->merge[i]->src;
97                 refspec.dst = NULL;
98                 refspec.pattern = 0;
99                 refspec.force = 0;
100                 get_fetch_map(remote_refs, &refspec, tail, 1);
101                 for (rm = *old_tail; rm; rm = rm->next)
102                         rm->merge = 1;
103         }
104 }
105
106 static void find_non_local_tags(struct transport *transport,
107                         struct ref **head,
108                         struct ref ***tail);
109
110 static struct ref *get_ref_map(struct transport *transport,
111                                struct refspec *refs, int ref_count, int tags,
112                                int *autotags)
113 {
114         int i;
115         struct ref *rm;
116         struct ref *ref_map = NULL;
117         struct ref **tail = &ref_map;
118
119         const struct ref *remote_refs = transport_get_remote_refs(transport);
120
121         if (ref_count || tags == TAGS_SET) {
122                 for (i = 0; i < ref_count; i++) {
123                         get_fetch_map(remote_refs, &refs[i], &tail, 0);
124                         if (refs[i].dst && refs[i].dst[0])
125                                 *autotags = 1;
126                 }
127                 /* Merge everything on the command line, but not --tags */
128                 for (rm = ref_map; rm; rm = rm->next)
129                         rm->merge = 1;
130                 if (tags == TAGS_SET) {
131                         struct refspec refspec;
132                         refspec.src = "refs/tags/";
133                         refspec.dst = "refs/tags/";
134                         refspec.pattern = 1;
135                         refspec.force = 0;
136                         get_fetch_map(remote_refs, &refspec, &tail, 0);
137                 }
138         } else {
139                 /* Use the defaults */
140                 struct remote *remote = transport->remote;
141                 struct branch *branch = branch_get(NULL);
142                 int has_merge = branch_has_merge_config(branch);
143                 if (remote && (remote->fetch_refspec_nr || has_merge)) {
144                         for (i = 0; i < remote->fetch_refspec_nr; i++) {
145                                 get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
146                                 if (remote->fetch[i].dst &&
147                                     remote->fetch[i].dst[0])
148                                         *autotags = 1;
149                                 if (!i && !has_merge && ref_map &&
150                                     !remote->fetch[0].pattern)
151                                         ref_map->merge = 1;
152                         }
153                         /*
154                          * if the remote we're fetching from is the same
155                          * as given in branch.<name>.remote, we add the
156                          * ref given in branch.<name>.merge, too.
157                          */
158                         if (has_merge &&
159                             !strcmp(branch->remote_name, remote->name))
160                                 add_merge_config(&ref_map, remote_refs, branch, &tail);
161                 } else {
162                         ref_map = get_remote_ref(remote_refs, "HEAD");
163                         if (!ref_map)
164                                 die("Couldn't find remote ref HEAD");
165                         ref_map->merge = 1;
166                         tail = &ref_map->next;
167                 }
168         }
169         if (tags == TAGS_DEFAULT && *autotags)
170                 find_non_local_tags(transport, &ref_map, &tail);
171         ref_remove_duplicates(ref_map);
172
173         return ref_map;
174 }
175
176 static int s_update_ref(const char *action,
177                         struct ref *ref,
178                         int check_old)
179 {
180         char msg[1024];
181         char *rla = getenv("GIT_REFLOG_ACTION");
182         static struct ref_lock *lock;
183
184         if (!rla)
185                 rla = default_rla.buf;
186         snprintf(msg, sizeof(msg), "%s: %s", rla, action);
187         lock = lock_any_ref_for_update(ref->name,
188                                        check_old ? ref->old_sha1 : NULL, 0);
189         if (!lock)
190                 return 1;
191         if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
192                 return 1;
193         return 0;
194 }
195
196 #define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
197 #define REFCOL_WIDTH  10
198
199 static int update_local_ref(struct ref *ref,
200                             const char *remote,
201                             int verbose,
202                             char *display)
203 {
204         struct commit *current = NULL, *updated;
205         enum object_type type;
206         struct branch *current_branch = branch_get(NULL);
207         const char *pretty_ref = ref->name + (
208                 !prefixcmp(ref->name, "refs/heads/") ? 11 :
209                 !prefixcmp(ref->name, "refs/tags/") ? 10 :
210                 !prefixcmp(ref->name, "refs/remotes/") ? 13 :
211                 0);
212
213         *display = 0;
214         type = sha1_object_info(ref->new_sha1, NULL);
215         if (type < 0)
216                 die("object %s not found", sha1_to_hex(ref->new_sha1));
217
218         if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
219                 if (verbose)
220                         sprintf(display, "= %-*s %-*s -> %s", SUMMARY_WIDTH,
221                                 "[up to date]", REFCOL_WIDTH, remote,
222                                 pretty_ref);
223                 return 0;
224         }
225
226         if (current_branch &&
227             !strcmp(ref->name, current_branch->name) &&
228             !(update_head_ok || is_bare_repository()) &&
229             !is_null_sha1(ref->old_sha1)) {
230                 /*
231                  * If this is the head, and it's not okay to update
232                  * the head, and the old value of the head isn't empty...
233                  */
234                 sprintf(display, "! %-*s %-*s -> %s  (can't fetch in current branch)",
235                         SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
236                         pretty_ref);
237                 return 1;
238         }
239
240         if (!is_null_sha1(ref->old_sha1) &&
241             !prefixcmp(ref->name, "refs/tags/")) {
242                 sprintf(display, "- %-*s %-*s -> %s",
243                         SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
244                         pretty_ref);
245                 return s_update_ref("updating tag", ref, 0);
246         }
247
248         current = lookup_commit_reference_gently(ref->old_sha1, 1);
249         updated = lookup_commit_reference_gently(ref->new_sha1, 1);
250         if (!current || !updated) {
251                 const char *msg;
252                 const char *what;
253                 if (!strncmp(ref->name, "refs/tags/", 10)) {
254                         msg = "storing tag";
255                         what = "[new tag]";
256                 }
257                 else {
258                         msg = "storing head";
259                         what = "[new branch]";
260                 }
261
262                 sprintf(display, "* %-*s %-*s -> %s", SUMMARY_WIDTH, what,
263                         REFCOL_WIDTH, remote, pretty_ref);
264                 return s_update_ref(msg, ref, 0);
265         }
266
267         if (in_merge_bases(current, &updated, 1)) {
268                 char quickref[83];
269                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
270                 strcat(quickref, "..");
271                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
272                 sprintf(display, "  %-*s %-*s -> %s", SUMMARY_WIDTH, quickref,
273                         REFCOL_WIDTH, remote, pretty_ref);
274                 return s_update_ref("fast forward", ref, 1);
275         } else if (force || ref->force) {
276                 char quickref[84];
277                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
278                 strcat(quickref, "...");
279                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
280                 sprintf(display, "+ %-*s %-*s -> %s  (forced update)",
281                         SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote, pretty_ref);
282                 return s_update_ref("forced-update", ref, 1);
283         } else {
284                 sprintf(display, "! %-*s %-*s -> %s  (non fast forward)",
285                         SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
286                         pretty_ref);
287                 return 1;
288         }
289 }
290
291 static int store_updated_refs(const char *url, struct ref *ref_map)
292 {
293         FILE *fp;
294         struct commit *commit;
295         int url_len, i, note_len, shown_url = 0;
296         char note[1024];
297         const char *what, *kind;
298         struct ref *rm;
299         char *filename = git_path("FETCH_HEAD");
300
301         fp = fopen(filename, "a");
302         if (!fp)
303                 return error("cannot open %s: %s\n", filename, strerror(errno));
304         for (rm = ref_map; rm; rm = rm->next) {
305                 struct ref *ref = NULL;
306
307                 if (rm->peer_ref) {
308                         ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
309                         strcpy(ref->name, rm->peer_ref->name);
310                         hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
311                         hashcpy(ref->new_sha1, rm->old_sha1);
312                         ref->force = rm->peer_ref->force;
313                 }
314
315                 commit = lookup_commit_reference_gently(rm->old_sha1, 1);
316                 if (!commit)
317                         rm->merge = 0;
318
319                 if (!strcmp(rm->name, "HEAD")) {
320                         kind = "";
321                         what = "";
322                 }
323                 else if (!prefixcmp(rm->name, "refs/heads/")) {
324                         kind = "branch";
325                         what = rm->name + 11;
326                 }
327                 else if (!prefixcmp(rm->name, "refs/tags/")) {
328                         kind = "tag";
329                         what = rm->name + 10;
330                 }
331                 else if (!prefixcmp(rm->name, "refs/remotes/")) {
332                         kind = "remote branch";
333                         what = rm->name + 13;
334                 }
335                 else {
336                         kind = "";
337                         what = rm->name;
338                 }
339
340                 url_len = strlen(url);
341                 for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
342                         ;
343                 url_len = i + 1;
344                 if (4 < i && !strncmp(".git", url + i - 3, 4))
345                         url_len = i - 3;
346
347                 note_len = 0;
348                 if (*what) {
349                         if (*kind)
350                                 note_len += sprintf(note + note_len, "%s ",
351                                                     kind);
352                         note_len += sprintf(note + note_len, "'%s' of ", what);
353                 }
354                 note_len += sprintf(note + note_len, "%.*s", url_len, url);
355                 fprintf(fp, "%s\t%s\t%s\n",
356                         sha1_to_hex(commit ? commit->object.sha1 :
357                                     rm->old_sha1),
358                         rm->merge ? "" : "not-for-merge",
359                         note);
360
361                 if (ref)
362                         update_local_ref(ref, what, verbose, note);
363                 else if (verbose)
364                         sprintf(note, "* %-*s %-*s -> FETCH_HEAD",
365                                 SUMMARY_WIDTH, *kind ? kind : "branch",
366                                  REFCOL_WIDTH, *what ? what : "HEAD");
367                 else
368                         *note = '\0';
369                 if (*note) {
370                         if (!shown_url) {
371                                 fprintf(stderr, "From %.*s\n",
372                                                 url_len, url);
373                                 shown_url = 1;
374                         }
375                         fprintf(stderr, " %s\n", note);
376                 }
377         }
378         fclose(fp);
379         return 0;
380 }
381
382 /*
383  * We would want to bypass the object transfer altogether if
384  * everything we are going to fetch already exists and connected
385  * locally.
386  *
387  * The refs we are going to fetch are in to_fetch (nr_heads in
388  * total).  If running
389  *
390  *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
391  *
392  * does not error out, that means everything reachable from the
393  * refs we are going to fetch exists and is connected to some of
394  * our existing refs.
395  */
396 static int quickfetch(struct ref *ref_map)
397 {
398         struct child_process revlist;
399         struct ref *ref;
400         char **argv;
401         int i, err;
402
403         /*
404          * If we are deepening a shallow clone we already have these
405          * objects reachable.  Running rev-list here will return with
406          * a good (0) exit status and we'll bypass the fetch that we
407          * really need to perform.  Claiming failure now will ensure
408          * we perform the network exchange to deepen our history.
409          */
410         if (depth)
411                 return -1;
412
413         for (i = 0, ref = ref_map; ref; ref = ref->next)
414                 i++;
415         if (!i)
416                 return 0;
417
418         argv = xmalloc(sizeof(*argv) * (i + 6));
419         i = 0;
420         argv[i++] = xstrdup("rev-list");
421         argv[i++] = xstrdup("--quiet");
422         argv[i++] = xstrdup("--objects");
423         for (ref = ref_map; ref; ref = ref->next)
424                 argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
425         argv[i++] = xstrdup("--not");
426         argv[i++] = xstrdup("--all");
427         argv[i++] = NULL;
428
429         memset(&revlist, 0, sizeof(revlist));
430         revlist.argv = (const char**)argv;
431         revlist.git_cmd = 1;
432         revlist.no_stdin = 1;
433         revlist.no_stdout = 1;
434         revlist.no_stderr = 1;
435         err = run_command(&revlist);
436
437         for (i = 0; argv[i]; i++)
438                 free(argv[i]);
439         free(argv);
440         return err;
441 }
442
443 static int fetch_refs(struct transport *transport, struct ref *ref_map)
444 {
445         int ret = quickfetch(ref_map);
446         if (ret)
447                 ret = transport_fetch_refs(transport, ref_map);
448         if (!ret)
449                 ret |= store_updated_refs(transport->url, ref_map);
450         transport_unlock_pack(transport);
451         return ret;
452 }
453
454 static int add_existing(const char *refname, const unsigned char *sha1,
455                         int flag, void *cbdata)
456 {
457         struct path_list *list = (struct path_list *)cbdata;
458         path_list_insert(refname, list);
459         return 0;
460 }
461
462 static int will_fetch(struct ref **head, const unsigned char *sha1)
463 {
464         struct ref *rm = *head;
465         while (rm) {
466                 if (!hashcmp(rm->old_sha1, sha1))
467                         return 1;
468                 rm = rm->next;
469         }
470         return 0;
471 }
472
473 static void find_non_local_tags(struct transport *transport,
474                         struct ref **head,
475                         struct ref ***tail)
476 {
477         struct path_list existing_refs = { NULL, 0, 0, 0 };
478         struct path_list new_refs = { NULL, 0, 0, 1 };
479         char *ref_name;
480         int ref_name_len;
481         const unsigned char *ref_sha1;
482         const struct ref *tag_ref;
483         struct ref *rm = NULL;
484         const struct ref *ref;
485
486         for_each_ref(add_existing, &existing_refs);
487         for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
488                 if (prefixcmp(ref->name, "refs/tags"))
489                         continue;
490
491                 ref_name = xstrdup(ref->name);
492                 ref_name_len = strlen(ref_name);
493                 ref_sha1 = ref->old_sha1;
494
495                 if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
496                         ref_name[ref_name_len - 3] = 0;
497                         tag_ref = transport_get_remote_refs(transport);
498                         while (tag_ref) {
499                                 if (!strcmp(tag_ref->name, ref_name)) {
500                                         ref_sha1 = tag_ref->old_sha1;
501                                         break;
502                                 }
503                                 tag_ref = tag_ref->next;
504                         }
505                 }
506
507                 if (!path_list_has_path(&existing_refs, ref_name) &&
508                     !path_list_has_path(&new_refs, ref_name) &&
509                     (has_sha1_file(ref->old_sha1) ||
510                      will_fetch(head, ref->old_sha1))) {
511                         path_list_insert(ref_name, &new_refs);
512
513                         rm = alloc_ref(strlen(ref_name) + 1);
514                         strcpy(rm->name, ref_name);
515                         rm->peer_ref = alloc_ref(strlen(ref_name) + 1);
516                         strcpy(rm->peer_ref->name, ref_name);
517                         hashcpy(rm->old_sha1, ref_sha1);
518
519                         **tail = rm;
520                         *tail = &rm->next;
521                 }
522                 free(ref_name);
523         }
524         path_list_clear(&existing_refs, 0);
525         path_list_clear(&new_refs, 0);
526 }
527
528 static int do_fetch(struct transport *transport,
529                     struct refspec *refs, int ref_count)
530 {
531         struct ref *ref_map;
532         struct ref *rm;
533         int autotags = (transport->remote->fetch_tags == 1);
534         if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
535                 tags = TAGS_SET;
536         if (transport->remote->fetch_tags == -1)
537                 tags = TAGS_UNSET;
538
539         if (!transport->get_refs_list || !transport->fetch)
540                 die("Don't know how to fetch from %s", transport->url);
541
542         /* if not appending, truncate FETCH_HEAD */
543         if (!append) {
544                 char *filename = git_path("FETCH_HEAD");
545                 FILE *fp = fopen(filename, "w");
546                 if (!fp)
547                         return error("cannot open %s: %s\n", filename, strerror(errno));
548                 fclose(fp);
549         }
550
551         ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
552
553         for (rm = ref_map; rm; rm = rm->next) {
554                 if (rm->peer_ref)
555                         read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
556         }
557
558         if (tags == TAGS_DEFAULT && autotags)
559                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
560         if (fetch_refs(transport, ref_map)) {
561                 free_refs(ref_map);
562                 return 1;
563         }
564         free_refs(ref_map);
565
566         /* if neither --no-tags nor --tags was specified, do automated tag
567          * following ... */
568         if (tags == TAGS_DEFAULT && autotags) {
569                 struct ref **tail = &ref_map;
570                 ref_map = NULL;
571                 find_non_local_tags(transport, &ref_map, &tail);
572                 if (ref_map) {
573                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
574                         transport_set_option(transport, TRANS_OPT_DEPTH, "0");
575                         fetch_refs(transport, ref_map);
576                 }
577                 free_refs(ref_map);
578         }
579
580         transport_disconnect(transport);
581
582         return 0;
583 }
584
585 static void set_option(const char *name, const char *value)
586 {
587         int r = transport_set_option(transport, name, value);
588         if (r < 0)
589                 die("Option \"%s\" value \"%s\" is not valid for %s\n",
590                         name, value, transport->url);
591         if (r > 0)
592                 warning("Option \"%s\" is ignored for %s\n",
593                         name, transport->url);
594 }
595
596 int cmd_fetch(int argc, const char **argv, const char *prefix)
597 {
598         struct remote *remote;
599         int i;
600         static const char **refs = NULL;
601         int ref_nr = 0;
602
603         /* Record the command line for the reflog */
604         strbuf_addstr(&default_rla, "fetch");
605         for (i = 1; i < argc; i++)
606                 strbuf_addf(&default_rla, " %s", argv[i]);
607
608         argc = parse_options(argc, argv,
609                              builtin_fetch_options, builtin_fetch_usage, 0);
610
611         if (argc == 0)
612                 remote = remote_get(NULL);
613         else
614                 remote = remote_get(argv[0]);
615
616         transport = transport_get(remote, remote->url[0]);
617         if (verbose >= 2)
618                 transport->verbose = 1;
619         if (quiet)
620                 transport->verbose = -1;
621         if (upload_pack)
622                 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
623         if (keep)
624                 set_option(TRANS_OPT_KEEP, "yes");
625         if (depth)
626                 set_option(TRANS_OPT_DEPTH, depth);
627
628         if (!transport->url)
629                 die("Where do you want to fetch from today?");
630
631         if (argc > 1) {
632                 int j = 0;
633                 refs = xcalloc(argc + 1, sizeof(const char *));
634                 for (i = 1; i < argc; i++) {
635                         if (!strcmp(argv[i], "tag")) {
636                                 char *ref;
637                                 i++;
638                                 if (i >= argc)
639                                         die("You need to specify a tag name.");
640                                 ref = xmalloc(strlen(argv[i]) * 2 + 22);
641                                 strcpy(ref, "refs/tags/");
642                                 strcat(ref, argv[i]);
643                                 strcat(ref, ":refs/tags/");
644                                 strcat(ref, argv[i]);
645                                 refs[j++] = ref;
646                         } else
647                                 refs[j++] = argv[i];
648                 }
649                 refs[j] = NULL;
650                 ref_nr = j;
651         }
652
653         signal(SIGINT, unlock_pack_on_signal);
654         atexit(unlock_pack);
655         return do_fetch(transport,
656                         parse_fetch_refspec(ref_nr, refs), ref_nr);
657 }