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