git-remote-mediawiki: get rid of O(N^2) loop
[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 "string-list.h"
9 #include "remote.h"
10 #include "transport.h"
11 #include "run-command.h"
12 #include "parse-options.h"
13 #include "sigchain.h"
14 #include "transport.h"
15 #include "submodule.h"
16 #include "connected.h"
17
18 static const char * const builtin_fetch_usage[] = {
19         "git fetch [<options>] [<repository> [<refspec>...]]",
20         "git fetch [<options>] <group>",
21         "git fetch --multiple [<options>] [(<repository> | <group>)...]",
22         "git fetch --all [<options>]",
23         NULL
24 };
25
26 enum {
27         TAGS_UNSET = 0,
28         TAGS_DEFAULT = 1,
29         TAGS_SET = 2
30 };
31
32 static int all, append, dry_run, force, keep, multiple, prune, update_head_ok, verbosity;
33 static int progress = -1, recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
34 static int tags = TAGS_DEFAULT;
35 static const char *depth;
36 static const char *upload_pack;
37 static struct strbuf default_rla = STRBUF_INIT;
38 static struct transport *transport;
39 static const char *submodule_prefix = "";
40 static const char *recurse_submodules_default;
41
42 static int option_parse_recurse_submodules(const struct option *opt,
43                                    const char *arg, int unset)
44 {
45         if (unset) {
46                 recurse_submodules = RECURSE_SUBMODULES_OFF;
47         } else {
48                 if (arg)
49                         recurse_submodules = parse_fetch_recurse_submodules_arg(opt->long_name, arg);
50                 else
51                         recurse_submodules = RECURSE_SUBMODULES_ON;
52         }
53         return 0;
54 }
55
56 static struct option builtin_fetch_options[] = {
57         OPT__VERBOSITY(&verbosity),
58         OPT_BOOLEAN(0, "all", &all,
59                     "fetch from all remotes"),
60         OPT_BOOLEAN('a', "append", &append,
61                     "append to .git/FETCH_HEAD instead of overwriting"),
62         OPT_STRING(0, "upload-pack", &upload_pack, "path",
63                    "path to upload pack on remote end"),
64         OPT__FORCE(&force, "force overwrite of local branch"),
65         OPT_BOOLEAN('m', "multiple", &multiple,
66                     "fetch from multiple remotes"),
67         OPT_SET_INT('t', "tags", &tags,
68                     "fetch all tags and associated objects", TAGS_SET),
69         OPT_SET_INT('n', NULL, &tags,
70                     "do not fetch all tags (--no-tags)", TAGS_UNSET),
71         OPT_BOOLEAN('p', "prune", &prune,
72                     "prune remote-tracking branches no longer on remote"),
73         { OPTION_CALLBACK, 0, "recurse-submodules", NULL, "on-demand",
74                     "control recursive fetching of submodules",
75                     PARSE_OPT_OPTARG, option_parse_recurse_submodules },
76         OPT_BOOLEAN(0, "dry-run", &dry_run,
77                     "dry run"),
78         OPT_BOOLEAN('k', "keep", &keep, "keep downloaded pack"),
79         OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
80                     "allow updating of HEAD ref"),
81         OPT_BOOL(0, "progress", &progress, "force progress reporting"),
82         OPT_STRING(0, "depth", &depth, "depth",
83                    "deepen history of shallow clone"),
84         { OPTION_STRING, 0, "submodule-prefix", &submodule_prefix, "dir",
85                    "prepend this to submodule path output", PARSE_OPT_HIDDEN },
86         { OPTION_STRING, 0, "recurse-submodules-default",
87                    &recurse_submodules_default, NULL,
88                    "default mode for recursion", PARSE_OPT_HIDDEN },
89         OPT_END()
90 };
91
92 static void unlock_pack(void)
93 {
94         if (transport)
95                 transport_unlock_pack(transport);
96 }
97
98 static void unlock_pack_on_signal(int signo)
99 {
100         unlock_pack();
101         sigchain_pop(signo);
102         raise(signo);
103 }
104
105 static void add_merge_config(struct ref **head,
106                            const struct ref *remote_refs,
107                            struct branch *branch,
108                            struct ref ***tail)
109 {
110         int i;
111
112         for (i = 0; i < branch->merge_nr; i++) {
113                 struct ref *rm, **old_tail = *tail;
114                 struct refspec refspec;
115
116                 for (rm = *head; rm; rm = rm->next) {
117                         if (branch_merge_matches(branch, i, rm->name)) {
118                                 rm->merge = 1;
119                                 break;
120                         }
121                 }
122                 if (rm)
123                         continue;
124
125                 /*
126                  * Not fetched to a remote-tracking branch?  We need to fetch
127                  * it anyway to allow this branch's "branch.$name.merge"
128                  * to be honored by 'git pull', but we do not have to
129                  * fail if branch.$name.merge is misconfigured to point
130                  * at a nonexisting branch.  If we were indeed called by
131                  * 'git pull', it will notice the misconfiguration because
132                  * there is no entry in the resulting FETCH_HEAD marked
133                  * for merging.
134                  */
135                 memset(&refspec, 0, sizeof(refspec));
136                 refspec.src = branch->merge[i]->src;
137                 get_fetch_map(remote_refs, &refspec, tail, 1);
138                 for (rm = *old_tail; rm; rm = rm->next)
139                         rm->merge = 1;
140         }
141 }
142
143 static void find_non_local_tags(struct transport *transport,
144                         struct ref **head,
145                         struct ref ***tail);
146
147 static struct ref *get_ref_map(struct transport *transport,
148                                struct refspec *refs, int ref_count, int tags,
149                                int *autotags)
150 {
151         int i;
152         struct ref *rm;
153         struct ref *ref_map = NULL;
154         struct ref **tail = &ref_map;
155
156         const struct ref *remote_refs = transport_get_remote_refs(transport);
157
158         if (ref_count || tags == TAGS_SET) {
159                 for (i = 0; i < ref_count; i++) {
160                         get_fetch_map(remote_refs, &refs[i], &tail, 0);
161                         if (refs[i].dst && refs[i].dst[0])
162                                 *autotags = 1;
163                 }
164                 /* Merge everything on the command line, but not --tags */
165                 for (rm = ref_map; rm; rm = rm->next)
166                         rm->merge = 1;
167                 if (tags == TAGS_SET)
168                         get_fetch_map(remote_refs, tag_refspec, &tail, 0);
169         } else {
170                 /* Use the defaults */
171                 struct remote *remote = transport->remote;
172                 struct branch *branch = branch_get(NULL);
173                 int has_merge = branch_has_merge_config(branch);
174                 if (remote &&
175                     (remote->fetch_refspec_nr ||
176                      /* Note: has_merge implies non-NULL branch->remote_name */
177                      (has_merge && !strcmp(branch->remote_name, remote->name)))) {
178                         for (i = 0; i < remote->fetch_refspec_nr; i++) {
179                                 get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
180                                 if (remote->fetch[i].dst &&
181                                     remote->fetch[i].dst[0])
182                                         *autotags = 1;
183                                 if (!i && !has_merge && ref_map &&
184                                     !remote->fetch[0].pattern)
185                                         ref_map->merge = 1;
186                         }
187                         /*
188                          * if the remote we're fetching from is the same
189                          * as given in branch.<name>.remote, we add the
190                          * ref given in branch.<name>.merge, too.
191                          *
192                          * Note: has_merge implies non-NULL branch->remote_name
193                          */
194                         if (has_merge &&
195                             !strcmp(branch->remote_name, remote->name))
196                                 add_merge_config(&ref_map, remote_refs, branch, &tail);
197                 } else {
198                         ref_map = get_remote_ref(remote_refs, "HEAD");
199                         if (!ref_map)
200                                 die(_("Couldn't find remote ref HEAD"));
201                         ref_map->merge = 1;
202                         tail = &ref_map->next;
203                 }
204         }
205         if (tags == TAGS_DEFAULT && *autotags)
206                 find_non_local_tags(transport, &ref_map, &tail);
207         ref_remove_duplicates(ref_map);
208
209         return ref_map;
210 }
211
212 #define STORE_REF_ERROR_OTHER 1
213 #define STORE_REF_ERROR_DF_CONFLICT 2
214
215 static int s_update_ref(const char *action,
216                         struct ref *ref,
217                         int check_old)
218 {
219         char msg[1024];
220         char *rla = getenv("GIT_REFLOG_ACTION");
221         static struct ref_lock *lock;
222
223         if (dry_run)
224                 return 0;
225         if (!rla)
226                 rla = default_rla.buf;
227         snprintf(msg, sizeof(msg), "%s: %s", rla, action);
228         lock = lock_any_ref_for_update(ref->name,
229                                        check_old ? ref->old_sha1 : NULL, 0);
230         if (!lock)
231                 return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
232                                           STORE_REF_ERROR_OTHER;
233         if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
234                 return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
235                                           STORE_REF_ERROR_OTHER;
236         return 0;
237 }
238
239 #define REFCOL_WIDTH  10
240
241 static int update_local_ref(struct ref *ref,
242                             const char *remote,
243                             const struct ref *remote_ref,
244                             struct strbuf *display)
245 {
246         struct commit *current = NULL, *updated;
247         enum object_type type;
248         struct branch *current_branch = branch_get(NULL);
249         const char *pretty_ref = prettify_refname(ref->name);
250
251         type = sha1_object_info(ref->new_sha1, NULL);
252         if (type < 0)
253                 die(_("object %s not found"), sha1_to_hex(ref->new_sha1));
254
255         if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
256                 if (verbosity > 0)
257                         strbuf_addf(display, "= %-*s %-*s -> %s",
258                                     TRANSPORT_SUMMARY_WIDTH,
259                                     _("[up to date]"), REFCOL_WIDTH,
260                                     remote, pretty_ref);
261                 return 0;
262         }
263
264         if (current_branch &&
265             !strcmp(ref->name, current_branch->name) &&
266             !(update_head_ok || is_bare_repository()) &&
267             !is_null_sha1(ref->old_sha1)) {
268                 /*
269                  * If this is the head, and it's not okay to update
270                  * the head, and the old value of the head isn't empty...
271                  */
272                 strbuf_addf(display,
273                             _("! %-*s %-*s -> %s  (can't fetch in current branch)"),
274                             TRANSPORT_SUMMARY_WIDTH, _("[rejected]"),
275                             REFCOL_WIDTH, remote, pretty_ref);
276                 return 1;
277         }
278
279         if (!is_null_sha1(ref->old_sha1) &&
280             !prefixcmp(ref->name, "refs/tags/")) {
281                 int r;
282                 r = s_update_ref("updating tag", ref, 0);
283                 strbuf_addf(display, "%c %-*s %-*s -> %s%s",
284                             r ? '!' : '-',
285                             TRANSPORT_SUMMARY_WIDTH, _("[tag update]"),
286                             REFCOL_WIDTH, remote, pretty_ref,
287                             r ? _("  (unable to update local ref)") : "");
288                 return r;
289         }
290
291         current = lookup_commit_reference_gently(ref->old_sha1, 1);
292         updated = lookup_commit_reference_gently(ref->new_sha1, 1);
293         if (!current || !updated) {
294                 const char *msg;
295                 const char *what;
296                 int r;
297                 /*
298                  * Nicely describe the new ref we're fetching.
299                  * Base this on the remote's ref name, as it's
300                  * more likely to follow a standard layout.
301                  */
302                 const char *name = remote_ref ? remote_ref->name : "";
303                 if (!prefixcmp(name, "refs/tags/")) {
304                         msg = "storing tag";
305                         what = _("[new tag]");
306                 } else if (!prefixcmp(name, "refs/heads/")) {
307                         msg = "storing head";
308                         what = _("[new branch]");
309                 } else {
310                         msg = "storing ref";
311                         what = _("[new ref]");
312                 }
313
314                 if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
315                     (recurse_submodules != RECURSE_SUBMODULES_ON))
316                         check_for_new_submodule_commits(ref->new_sha1);
317                 r = s_update_ref(msg, ref, 0);
318                 strbuf_addf(display, "%c %-*s %-*s -> %s%s",
319                             r ? '!' : '*',
320                             TRANSPORT_SUMMARY_WIDTH, what,
321                             REFCOL_WIDTH, remote, pretty_ref,
322                             r ? _("  (unable to update local ref)") : "");
323                 return r;
324         }
325
326         if (in_merge_bases(current, &updated, 1)) {
327                 char quickref[83];
328                 int r;
329                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
330                 strcat(quickref, "..");
331                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
332                 if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
333                     (recurse_submodules != RECURSE_SUBMODULES_ON))
334                         check_for_new_submodule_commits(ref->new_sha1);
335                 r = s_update_ref("fast-forward", ref, 1);
336                 strbuf_addf(display, "%c %-*s %-*s -> %s%s",
337                             r ? '!' : ' ',
338                             TRANSPORT_SUMMARY_WIDTH, quickref,
339                             REFCOL_WIDTH, remote, pretty_ref,
340                             r ? _("  (unable to update local ref)") : "");
341                 return r;
342         } else if (force || ref->force) {
343                 char quickref[84];
344                 int r;
345                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
346                 strcat(quickref, "...");
347                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
348                 if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
349                     (recurse_submodules != RECURSE_SUBMODULES_ON))
350                         check_for_new_submodule_commits(ref->new_sha1);
351                 r = s_update_ref("forced-update", ref, 1);
352                 strbuf_addf(display, "%c %-*s %-*s -> %s  (%s)",
353                             r ? '!' : '+',
354                             TRANSPORT_SUMMARY_WIDTH, quickref,
355                             REFCOL_WIDTH, remote, pretty_ref,
356                             r ? _("unable to update local ref") : _("forced update"));
357                 return r;
358         } else {
359                 strbuf_addf(display, "! %-*s %-*s -> %s  %s",
360                             TRANSPORT_SUMMARY_WIDTH, _("[rejected]"),
361                             REFCOL_WIDTH, remote, pretty_ref,
362                             _("(non-fast-forward)"));
363                 return 1;
364         }
365 }
366
367 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
368 {
369         struct ref **rm = cb_data;
370         struct ref *ref = *rm;
371
372         if (!ref)
373                 return -1; /* end of the list */
374         *rm = ref->next;
375         hashcpy(sha1, ref->old_sha1);
376         return 0;
377 }
378
379 static int store_updated_refs(const char *raw_url, const char *remote_name,
380                 struct ref *ref_map)
381 {
382         FILE *fp;
383         struct commit *commit;
384         int url_len, i, shown_url = 0, rc = 0;
385         struct strbuf note = STRBUF_INIT;
386         const char *what, *kind;
387         struct ref *rm;
388         char *url, *filename = dry_run ? "/dev/null" : git_path("FETCH_HEAD");
389         int want_merge;
390
391         fp = fopen(filename, "a");
392         if (!fp)
393                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
394
395         if (raw_url)
396                 url = transport_anonymize_url(raw_url);
397         else
398                 url = xstrdup("foreign");
399
400         rm = ref_map;
401         if (check_everything_connected(iterate_ref_map, 0, &rm)) {
402                 rc = error(_("%s did not send all necessary objects\n"), url);
403                 goto abort;
404         }
405
406         /*
407          * The first pass writes objects to be merged and then the
408          * second pass writes the rest, in order to allow using
409          * FETCH_HEAD as a refname to refer to the ref to be merged.
410          */
411         for (want_merge = 1; 0 <= want_merge; want_merge--) {
412                 for (rm = ref_map; rm; rm = rm->next) {
413                         struct ref *ref = NULL;
414
415                         commit = lookup_commit_reference_gently(rm->old_sha1, 1);
416                         if (!commit)
417                                 rm->merge = 0;
418
419                         if (rm->merge != want_merge)
420                                 continue;
421
422                         if (rm->peer_ref) {
423                                 ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
424                                 strcpy(ref->name, rm->peer_ref->name);
425                                 hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
426                                 hashcpy(ref->new_sha1, rm->old_sha1);
427                                 ref->force = rm->peer_ref->force;
428                         }
429
430
431                         if (!strcmp(rm->name, "HEAD")) {
432                                 kind = "";
433                                 what = "";
434                         }
435                         else if (!prefixcmp(rm->name, "refs/heads/")) {
436                                 kind = "branch";
437                                 what = rm->name + 11;
438                         }
439                         else if (!prefixcmp(rm->name, "refs/tags/")) {
440                                 kind = "tag";
441                                 what = rm->name + 10;
442                         }
443                         else if (!prefixcmp(rm->name, "refs/remotes/")) {
444                                 kind = "remote-tracking branch";
445                                 what = rm->name + 13;
446                         }
447                         else {
448                                 kind = "";
449                                 what = rm->name;
450                         }
451
452                         url_len = strlen(url);
453                         for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
454                                 ;
455                         url_len = i + 1;
456                         if (4 < i && !strncmp(".git", url + i - 3, 4))
457                                 url_len = i - 3;
458
459                         strbuf_reset(&note);
460                         if (*what) {
461                                 if (*kind)
462                                         strbuf_addf(&note, "%s ", kind);
463                                 strbuf_addf(&note, "'%s' of ", what);
464                         }
465                         fprintf(fp, "%s\t%s\t%s",
466                                 sha1_to_hex(rm->old_sha1),
467                                 rm->merge ? "" : "not-for-merge",
468                                 note.buf);
469                         for (i = 0; i < url_len; ++i)
470                                 if ('\n' == url[i])
471                                         fputs("\\n", fp);
472                                 else
473                                         fputc(url[i], fp);
474                         fputc('\n', fp);
475
476                         strbuf_reset(&note);
477                         if (ref) {
478                                 rc |= update_local_ref(ref, what, rm, &note);
479                                 free(ref);
480                         } else
481                                 strbuf_addf(&note, "* %-*s %-*s -> FETCH_HEAD",
482                                             TRANSPORT_SUMMARY_WIDTH,
483                                             *kind ? kind : "branch",
484                                             REFCOL_WIDTH,
485                                             *what ? what : "HEAD");
486                         if (note.len) {
487                                 if (verbosity >= 0 && !shown_url) {
488                                         fprintf(stderr, _("From %.*s\n"),
489                                                         url_len, url);
490                                         shown_url = 1;
491                                 }
492                                 if (verbosity >= 0)
493                                         fprintf(stderr, " %s\n", note.buf);
494                         }
495                 }
496         }
497
498         if (rc & STORE_REF_ERROR_DF_CONFLICT)
499                 error(_("some local refs could not be updated; try running\n"
500                       " 'git remote prune %s' to remove any old, conflicting "
501                       "branches"), remote_name);
502
503  abort:
504         strbuf_release(&note);
505         free(url);
506         fclose(fp);
507         return rc;
508 }
509
510 /*
511  * We would want to bypass the object transfer altogether if
512  * everything we are going to fetch already exists and is connected
513  * locally.
514  */
515 static int quickfetch(struct ref *ref_map)
516 {
517         struct ref *rm = ref_map;
518
519         /*
520          * If we are deepening a shallow clone we already have these
521          * objects reachable.  Running rev-list here will return with
522          * a good (0) exit status and we'll bypass the fetch that we
523          * really need to perform.  Claiming failure now will ensure
524          * we perform the network exchange to deepen our history.
525          */
526         if (depth)
527                 return -1;
528         return check_everything_connected(iterate_ref_map, 1, &rm);
529 }
530
531 static int fetch_refs(struct transport *transport, struct ref *ref_map)
532 {
533         int ret = quickfetch(ref_map);
534         if (ret)
535                 ret = transport_fetch_refs(transport, ref_map);
536         if (!ret)
537                 ret |= store_updated_refs(transport->url,
538                                 transport->remote->name,
539                                 ref_map);
540         transport_unlock_pack(transport);
541         return ret;
542 }
543
544 static int prune_refs(struct refspec *refs, int ref_count, struct ref *ref_map)
545 {
546         int result = 0;
547         struct ref *ref, *stale_refs = get_stale_heads(refs, ref_count, ref_map);
548         const char *dangling_msg = dry_run
549                 ? _("   (%s will become dangling)")
550                 : _("   (%s has become dangling)");
551
552         for (ref = stale_refs; ref; ref = ref->next) {
553                 if (!dry_run)
554                         result |= delete_ref(ref->name, NULL, 0);
555                 if (verbosity >= 0) {
556                         fprintf(stderr, " x %-*s %-*s -> %s\n",
557                                 TRANSPORT_SUMMARY_WIDTH, _("[deleted]"),
558                                 REFCOL_WIDTH, _("(none)"), prettify_refname(ref->name));
559                         warn_dangling_symref(stderr, dangling_msg, ref->name);
560                 }
561         }
562         free_refs(stale_refs);
563         return result;
564 }
565
566 static int add_existing(const char *refname, const unsigned char *sha1,
567                         int flag, void *cbdata)
568 {
569         struct string_list *list = (struct string_list *)cbdata;
570         struct string_list_item *item = string_list_insert(list, refname);
571         item->util = (void *)sha1;
572         return 0;
573 }
574
575 static int will_fetch(struct ref **head, const unsigned char *sha1)
576 {
577         struct ref *rm = *head;
578         while (rm) {
579                 if (!hashcmp(rm->old_sha1, sha1))
580                         return 1;
581                 rm = rm->next;
582         }
583         return 0;
584 }
585
586 static void find_non_local_tags(struct transport *transport,
587                         struct ref **head,
588                         struct ref ***tail)
589 {
590         struct string_list existing_refs = STRING_LIST_INIT_NODUP;
591         struct string_list remote_refs = STRING_LIST_INIT_NODUP;
592         const struct ref *ref;
593         struct string_list_item *item = NULL;
594
595         for_each_ref(add_existing, &existing_refs);
596         for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
597                 if (prefixcmp(ref->name, "refs/tags/"))
598                         continue;
599
600                 /*
601                  * The peeled ref always follows the matching base
602                  * ref, so if we see a peeled ref that we don't want
603                  * to fetch then we can mark the ref entry in the list
604                  * as one to ignore by setting util to NULL.
605                  */
606                 if (!suffixcmp(ref->name, "^{}")) {
607                         if (item && !has_sha1_file(ref->old_sha1) &&
608                             !will_fetch(head, ref->old_sha1) &&
609                             !has_sha1_file(item->util) &&
610                             !will_fetch(head, item->util))
611                                 item->util = NULL;
612                         item = NULL;
613                         continue;
614                 }
615
616                 /*
617                  * If item is non-NULL here, then we previously saw a
618                  * ref not followed by a peeled reference, so we need
619                  * to check if it is a lightweight tag that we want to
620                  * fetch.
621                  */
622                 if (item && !has_sha1_file(item->util) &&
623                     !will_fetch(head, item->util))
624                         item->util = NULL;
625
626                 item = NULL;
627
628                 /* skip duplicates and refs that we already have */
629                 if (string_list_has_string(&remote_refs, ref->name) ||
630                     string_list_has_string(&existing_refs, ref->name))
631                         continue;
632
633                 item = string_list_insert(&remote_refs, ref->name);
634                 item->util = (void *)ref->old_sha1;
635         }
636         string_list_clear(&existing_refs, 0);
637
638         /*
639          * We may have a final lightweight tag that needs to be
640          * checked to see if it needs fetching.
641          */
642         if (item && !has_sha1_file(item->util) &&
643             !will_fetch(head, item->util))
644                 item->util = NULL;
645
646         /*
647          * For all the tags in the remote_refs string list,
648          * add them to the list of refs to be fetched
649          */
650         for_each_string_list_item(item, &remote_refs) {
651                 /* Unless we have already decided to ignore this item... */
652                 if (item->util)
653                 {
654                         struct ref *rm = alloc_ref(item->string);
655                         rm->peer_ref = alloc_ref(item->string);
656                         hashcpy(rm->old_sha1, item->util);
657                         **tail = rm;
658                         *tail = &rm->next;
659                 }
660         }
661
662         string_list_clear(&remote_refs, 0);
663 }
664
665 static void check_not_current_branch(struct ref *ref_map)
666 {
667         struct branch *current_branch = branch_get(NULL);
668
669         if (is_bare_repository() || !current_branch)
670                 return;
671
672         for (; ref_map; ref_map = ref_map->next)
673                 if (ref_map->peer_ref && !strcmp(current_branch->refname,
674                                         ref_map->peer_ref->name))
675                         die(_("Refusing to fetch into current branch %s "
676                             "of non-bare repository"), current_branch->refname);
677 }
678
679 static int truncate_fetch_head(void)
680 {
681         char *filename = git_path("FETCH_HEAD");
682         FILE *fp = fopen(filename, "w");
683
684         if (!fp)
685                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
686         fclose(fp);
687         return 0;
688 }
689
690 static int do_fetch(struct transport *transport,
691                     struct refspec *refs, int ref_count)
692 {
693         struct string_list existing_refs = STRING_LIST_INIT_NODUP;
694         struct string_list_item *peer_item = NULL;
695         struct ref *ref_map;
696         struct ref *rm;
697         int autotags = (transport->remote->fetch_tags == 1);
698
699         for_each_ref(add_existing, &existing_refs);
700
701         if (tags == TAGS_DEFAULT) {
702                 if (transport->remote->fetch_tags == 2)
703                         tags = TAGS_SET;
704                 if (transport->remote->fetch_tags == -1)
705                         tags = TAGS_UNSET;
706         }
707
708         if (!transport->get_refs_list || !transport->fetch)
709                 die(_("Don't know how to fetch from %s"), transport->url);
710
711         /* if not appending, truncate FETCH_HEAD */
712         if (!append && !dry_run) {
713                 int errcode = truncate_fetch_head();
714                 if (errcode)
715                         return errcode;
716         }
717
718         ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
719         if (!update_head_ok)
720                 check_not_current_branch(ref_map);
721
722         for (rm = ref_map; rm; rm = rm->next) {
723                 if (rm->peer_ref) {
724                         peer_item = string_list_lookup(&existing_refs,
725                                                        rm->peer_ref->name);
726                         if (peer_item)
727                                 hashcpy(rm->peer_ref->old_sha1,
728                                         peer_item->util);
729                 }
730         }
731
732         if (tags == TAGS_DEFAULT && autotags)
733                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
734         if (fetch_refs(transport, ref_map)) {
735                 free_refs(ref_map);
736                 return 1;
737         }
738         if (prune) {
739                 /* If --tags was specified, pretend the user gave us the canonical tags refspec */
740                 if (tags == TAGS_SET) {
741                         const char *tags_str = "refs/tags/*:refs/tags/*";
742                         struct refspec *tags_refspec, *refspec;
743
744                         /* Copy the refspec and add the tags to it */
745                         refspec = xcalloc(ref_count + 1, sizeof(struct refspec));
746                         tags_refspec = parse_fetch_refspec(1, &tags_str);
747                         memcpy(refspec, refs, ref_count * sizeof(struct refspec));
748                         memcpy(&refspec[ref_count], tags_refspec, sizeof(struct refspec));
749                         ref_count++;
750
751                         prune_refs(refspec, ref_count, ref_map);
752
753                         ref_count--;
754                         /* The rest of the strings belong to fetch_one */
755                         free_refspec(1, tags_refspec);
756                         free(refspec);
757                 } else if (ref_count) {
758                         prune_refs(refs, ref_count, ref_map);
759                 } else {
760                         prune_refs(transport->remote->fetch, transport->remote->fetch_refspec_nr, ref_map);
761                 }
762         }
763         free_refs(ref_map);
764
765         /* if neither --no-tags nor --tags was specified, do automated tag
766          * following ... */
767         if (tags == TAGS_DEFAULT && autotags) {
768                 struct ref **tail = &ref_map;
769                 ref_map = NULL;
770                 find_non_local_tags(transport, &ref_map, &tail);
771                 if (ref_map) {
772                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
773                         transport_set_option(transport, TRANS_OPT_DEPTH, "0");
774                         fetch_refs(transport, ref_map);
775                 }
776                 free_refs(ref_map);
777         }
778
779         return 0;
780 }
781
782 static void set_option(const char *name, const char *value)
783 {
784         int r = transport_set_option(transport, name, value);
785         if (r < 0)
786                 die(_("Option \"%s\" value \"%s\" is not valid for %s"),
787                         name, value, transport->url);
788         if (r > 0)
789                 warning(_("Option \"%s\" is ignored for %s\n"),
790                         name, transport->url);
791 }
792
793 static int get_one_remote_for_fetch(struct remote *remote, void *priv)
794 {
795         struct string_list *list = priv;
796         if (!remote->skip_default_update)
797                 string_list_append(list, remote->name);
798         return 0;
799 }
800
801 struct remote_group_data {
802         const char *name;
803         struct string_list *list;
804 };
805
806 static int get_remote_group(const char *key, const char *value, void *priv)
807 {
808         struct remote_group_data *g = priv;
809
810         if (!prefixcmp(key, "remotes.") &&
811                         !strcmp(key + 8, g->name)) {
812                 /* split list by white space */
813                 int space = strcspn(value, " \t\n");
814                 while (*value) {
815                         if (space > 1) {
816                                 string_list_append(g->list,
817                                                    xstrndup(value, space));
818                         }
819                         value += space + (value[space] != '\0');
820                         space = strcspn(value, " \t\n");
821                 }
822         }
823
824         return 0;
825 }
826
827 static int add_remote_or_group(const char *name, struct string_list *list)
828 {
829         int prev_nr = list->nr;
830         struct remote_group_data g;
831         g.name = name; g.list = list;
832
833         git_config(get_remote_group, &g);
834         if (list->nr == prev_nr) {
835                 struct remote *remote;
836                 if (!remote_is_configured(name))
837                         return 0;
838                 remote = remote_get(name);
839                 string_list_append(list, remote->name);
840         }
841         return 1;
842 }
843
844 static void add_options_to_argv(int *argc, const char **argv)
845 {
846         if (dry_run)
847                 argv[(*argc)++] = "--dry-run";
848         if (prune)
849                 argv[(*argc)++] = "--prune";
850         if (update_head_ok)
851                 argv[(*argc)++] = "--update-head-ok";
852         if (force)
853                 argv[(*argc)++] = "--force";
854         if (keep)
855                 argv[(*argc)++] = "--keep";
856         if (recurse_submodules == RECURSE_SUBMODULES_ON)
857                 argv[(*argc)++] = "--recurse-submodules";
858         else if (recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)
859                 argv[(*argc)++] = "--recurse-submodules=on-demand";
860         if (verbosity >= 2)
861                 argv[(*argc)++] = "-v";
862         if (verbosity >= 1)
863                 argv[(*argc)++] = "-v";
864         else if (verbosity < 0)
865                 argv[(*argc)++] = "-q";
866
867 }
868
869 static int fetch_multiple(struct string_list *list)
870 {
871         int i, result = 0;
872         const char *argv[12] = { "fetch", "--append" };
873         int argc = 2;
874
875         add_options_to_argv(&argc, argv);
876
877         if (!append && !dry_run) {
878                 int errcode = truncate_fetch_head();
879                 if (errcode)
880                         return errcode;
881         }
882
883         for (i = 0; i < list->nr; i++) {
884                 const char *name = list->items[i].string;
885                 argv[argc] = name;
886                 argv[argc + 1] = NULL;
887                 if (verbosity >= 0)
888                         printf(_("Fetching %s\n"), name);
889                 if (run_command_v_opt(argv, RUN_GIT_CMD)) {
890                         error(_("Could not fetch %s"), name);
891                         result = 1;
892                 }
893         }
894
895         return result;
896 }
897
898 static int fetch_one(struct remote *remote, int argc, const char **argv)
899 {
900         int i;
901         static const char **refs = NULL;
902         struct refspec *refspec;
903         int ref_nr = 0;
904         int exit_code;
905
906         if (!remote)
907                 die(_("No remote repository specified.  Please, specify either a URL or a\n"
908                     "remote name from which new revisions should be fetched."));
909
910         transport = transport_get(remote, NULL);
911         transport_set_verbosity(transport, verbosity, progress);
912         if (upload_pack)
913                 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
914         if (keep)
915                 set_option(TRANS_OPT_KEEP, "yes");
916         if (depth)
917                 set_option(TRANS_OPT_DEPTH, depth);
918
919         if (argc > 0) {
920                 int j = 0;
921                 refs = xcalloc(argc + 1, sizeof(const char *));
922                 for (i = 0; i < argc; i++) {
923                         if (!strcmp(argv[i], "tag")) {
924                                 char *ref;
925                                 i++;
926                                 if (i >= argc)
927                                         die(_("You need to specify a tag name."));
928                                 ref = xmalloc(strlen(argv[i]) * 2 + 22);
929                                 strcpy(ref, "refs/tags/");
930                                 strcat(ref, argv[i]);
931                                 strcat(ref, ":refs/tags/");
932                                 strcat(ref, argv[i]);
933                                 refs[j++] = ref;
934                         } else
935                                 refs[j++] = argv[i];
936                 }
937                 refs[j] = NULL;
938                 ref_nr = j;
939         }
940
941         sigchain_push_common(unlock_pack_on_signal);
942         atexit(unlock_pack);
943         refspec = parse_fetch_refspec(ref_nr, refs);
944         exit_code = do_fetch(transport, refspec, ref_nr);
945         free_refspec(ref_nr, refspec);
946         transport_disconnect(transport);
947         transport = NULL;
948         return exit_code;
949 }
950
951 int cmd_fetch(int argc, const char **argv, const char *prefix)
952 {
953         int i;
954         struct string_list list = STRING_LIST_INIT_NODUP;
955         struct remote *remote;
956         int result = 0;
957
958         packet_trace_identity("fetch");
959
960         /* Record the command line for the reflog */
961         strbuf_addstr(&default_rla, "fetch");
962         for (i = 1; i < argc; i++)
963                 strbuf_addf(&default_rla, " %s", argv[i]);
964
965         argc = parse_options(argc, argv, prefix,
966                              builtin_fetch_options, builtin_fetch_usage, 0);
967
968         if (recurse_submodules != RECURSE_SUBMODULES_OFF) {
969                 if (recurse_submodules_default) {
970                         int arg = parse_fetch_recurse_submodules_arg("--recurse-submodules-default", recurse_submodules_default);
971                         set_config_fetch_recurse_submodules(arg);
972                 }
973                 gitmodules_config();
974                 git_config(submodule_config, NULL);
975         }
976
977         if (all) {
978                 if (argc == 1)
979                         die(_("fetch --all does not take a repository argument"));
980                 else if (argc > 1)
981                         die(_("fetch --all does not make sense with refspecs"));
982                 (void) for_each_remote(get_one_remote_for_fetch, &list);
983                 result = fetch_multiple(&list);
984         } else if (argc == 0) {
985                 /* No arguments -- use default remote */
986                 remote = remote_get(NULL);
987                 result = fetch_one(remote, argc, argv);
988         } else if (multiple) {
989                 /* All arguments are assumed to be remotes or groups */
990                 for (i = 0; i < argc; i++)
991                         if (!add_remote_or_group(argv[i], &list))
992                                 die(_("No such remote or remote group: %s"), argv[i]);
993                 result = fetch_multiple(&list);
994         } else {
995                 /* Single remote or group */
996                 (void) add_remote_or_group(argv[0], &list);
997                 if (list.nr > 1) {
998                         /* More than one remote */
999                         if (argc > 1)
1000                                 die(_("Fetching a group and specifying refspecs does not make sense"));
1001                         result = fetch_multiple(&list);
1002                 } else {
1003                         /* Zero or one remotes */
1004                         remote = remote_get(argv[0]);
1005                         result = fetch_one(remote, argc-1, argv+1);
1006                 }
1007         }
1008
1009         if (!result && (recurse_submodules != RECURSE_SUBMODULES_OFF)) {
1010                 const char *options[10];
1011                 int num_options = 0;
1012                 add_options_to_argv(&num_options, options);
1013                 result = fetch_populated_submodules(num_options, options,
1014                                                     submodule_prefix,
1015                                                     recurse_submodules,
1016                                                     verbosity < 0);
1017         }
1018
1019         /* All names were strdup()ed or strndup()ed */
1020         list.strdup_strings = 1;
1021         string_list_clear(&list, 0);
1022
1023         return result;
1024 }