Merge branch 'ns/am-abort'
[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 2;
185         if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
186                 return 2;
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                 int r;
237                 r = s_update_ref("updating tag", ref, 0);
238                 sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : '-',
239                         SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
240                         pretty_ref, r ? "  (unable to update local ref)" : "");
241                 return r;
242         }
243
244         current = lookup_commit_reference_gently(ref->old_sha1, 1);
245         updated = lookup_commit_reference_gently(ref->new_sha1, 1);
246         if (!current || !updated) {
247                 const char *msg;
248                 const char *what;
249                 int r;
250                 if (!strncmp(ref->name, "refs/tags/", 10)) {
251                         msg = "storing tag";
252                         what = "[new tag]";
253                 }
254                 else {
255                         msg = "storing head";
256                         what = "[new branch]";
257                 }
258
259                 r = s_update_ref(msg, ref, 0);
260                 sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : '*',
261                         SUMMARY_WIDTH, what, REFCOL_WIDTH, remote, pretty_ref,
262                         r ? "  (unable to update local ref)" : "");
263                 return r;
264         }
265
266         if (in_merge_bases(current, &updated, 1)) {
267                 char quickref[83];
268                 int r;
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                 r = s_update_ref("fast forward", ref, 1);
273                 sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : ' ',
274                         SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote,
275                         pretty_ref, r ? "  (unable to update local ref)" : "");
276                 return r;
277         } else if (force || ref->force) {
278                 char quickref[84];
279                 int r;
280                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
281                 strcat(quickref, "...");
282                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
283                 r = s_update_ref("forced-update", ref, 1);
284                 sprintf(display, "%c %-*s %-*s -> %s  (%s)", r ? '!' : '+',
285                         SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote,
286                         pretty_ref,
287                         r ? "unable to update local ref" : "forced update");
288                 return r;
289         } else {
290                 sprintf(display, "! %-*s %-*s -> %s  (non fast forward)",
291                         SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
292                         pretty_ref);
293                 return 1;
294         }
295 }
296
297 static int store_updated_refs(const char *url, const char *remote_name,
298                 struct ref *ref_map)
299 {
300         FILE *fp;
301         struct commit *commit;
302         int url_len, i, note_len, shown_url = 0, rc = 0;
303         char note[1024];
304         const char *what, *kind;
305         struct ref *rm;
306         char *filename = git_path("FETCH_HEAD");
307
308         fp = fopen(filename, "a");
309         if (!fp)
310                 return error("cannot open %s: %s\n", filename, strerror(errno));
311         for (rm = ref_map; rm; rm = rm->next) {
312                 struct ref *ref = NULL;
313
314                 if (rm->peer_ref) {
315                         ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
316                         strcpy(ref->name, rm->peer_ref->name);
317                         hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
318                         hashcpy(ref->new_sha1, rm->old_sha1);
319                         ref->force = rm->peer_ref->force;
320                 }
321
322                 commit = lookup_commit_reference_gently(rm->old_sha1, 1);
323                 if (!commit)
324                         rm->merge = 0;
325
326                 if (!strcmp(rm->name, "HEAD")) {
327                         kind = "";
328                         what = "";
329                 }
330                 else if (!prefixcmp(rm->name, "refs/heads/")) {
331                         kind = "branch";
332                         what = rm->name + 11;
333                 }
334                 else if (!prefixcmp(rm->name, "refs/tags/")) {
335                         kind = "tag";
336                         what = rm->name + 10;
337                 }
338                 else if (!prefixcmp(rm->name, "refs/remotes/")) {
339                         kind = "remote branch";
340                         what = rm->name + 13;
341                 }
342                 else {
343                         kind = "";
344                         what = rm->name;
345                 }
346
347                 url_len = strlen(url);
348                 for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
349                         ;
350                 url_len = i + 1;
351                 if (4 < i && !strncmp(".git", url + i - 3, 4))
352                         url_len = i - 3;
353
354                 note_len = 0;
355                 if (*what) {
356                         if (*kind)
357                                 note_len += sprintf(note + note_len, "%s ",
358                                                     kind);
359                         note_len += sprintf(note + note_len, "'%s' of ", what);
360                 }
361                 note_len += sprintf(note + note_len, "%.*s", url_len, url);
362                 fprintf(fp, "%s\t%s\t%s\n",
363                         sha1_to_hex(commit ? commit->object.sha1 :
364                                     rm->old_sha1),
365                         rm->merge ? "" : "not-for-merge",
366                         note);
367
368                 if (ref)
369                         rc |= update_local_ref(ref, what, verbose, note);
370                 else
371                         sprintf(note, "* %-*s %-*s -> FETCH_HEAD",
372                                 SUMMARY_WIDTH, *kind ? kind : "branch",
373                                  REFCOL_WIDTH, *what ? what : "HEAD");
374                 if (*note) {
375                         if (!shown_url) {
376                                 fprintf(stderr, "From %.*s\n",
377                                                 url_len, url);
378                                 shown_url = 1;
379                         }
380                         fprintf(stderr, " %s\n", note);
381                 }
382         }
383         fclose(fp);
384         if (rc & 2)
385                 error("some local refs could not be updated; try running\n"
386                       " 'git remote prune %s' to remove any old, conflicting "
387                       "branches", remote_name);
388         return rc;
389 }
390
391 /*
392  * We would want to bypass the object transfer altogether if
393  * everything we are going to fetch already exists and connected
394  * locally.
395  *
396  * The refs we are going to fetch are in to_fetch (nr_heads in
397  * total).  If running
398  *
399  *  $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
400  *
401  * does not error out, that means everything reachable from the
402  * refs we are going to fetch exists and is connected to some of
403  * our existing refs.
404  */
405 static int quickfetch(struct ref *ref_map)
406 {
407         struct child_process revlist;
408         struct ref *ref;
409         char **argv;
410         int i, err;
411
412         /*
413          * If we are deepening a shallow clone we already have these
414          * objects reachable.  Running rev-list here will return with
415          * a good (0) exit status and we'll bypass the fetch that we
416          * really need to perform.  Claiming failure now will ensure
417          * we perform the network exchange to deepen our history.
418          */
419         if (depth)
420                 return -1;
421
422         for (i = 0, ref = ref_map; ref; ref = ref->next)
423                 i++;
424         if (!i)
425                 return 0;
426
427         argv = xmalloc(sizeof(*argv) * (i + 6));
428         i = 0;
429         argv[i++] = xstrdup("rev-list");
430         argv[i++] = xstrdup("--quiet");
431         argv[i++] = xstrdup("--objects");
432         for (ref = ref_map; ref; ref = ref->next)
433                 argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
434         argv[i++] = xstrdup("--not");
435         argv[i++] = xstrdup("--all");
436         argv[i++] = NULL;
437
438         memset(&revlist, 0, sizeof(revlist));
439         revlist.argv = (const char**)argv;
440         revlist.git_cmd = 1;
441         revlist.no_stdin = 1;
442         revlist.no_stdout = 1;
443         revlist.no_stderr = 1;
444         err = run_command(&revlist);
445
446         for (i = 0; argv[i]; i++)
447                 free(argv[i]);
448         free(argv);
449         return err;
450 }
451
452 static int fetch_refs(struct transport *transport, struct ref *ref_map)
453 {
454         int ret = quickfetch(ref_map);
455         if (ret)
456                 ret = transport_fetch_refs(transport, ref_map);
457         if (!ret)
458                 ret |= store_updated_refs(transport->url,
459                                 transport->remote->name,
460                                 ref_map);
461         transport_unlock_pack(transport);
462         return ret;
463 }
464
465 static int add_existing(const char *refname, const unsigned char *sha1,
466                         int flag, void *cbdata)
467 {
468         struct path_list *list = (struct path_list *)cbdata;
469         path_list_insert(refname, list);
470         return 0;
471 }
472
473 static int will_fetch(struct ref **head, const unsigned char *sha1)
474 {
475         struct ref *rm = *head;
476         while (rm) {
477                 if (!hashcmp(rm->old_sha1, sha1))
478                         return 1;
479                 rm = rm->next;
480         }
481         return 0;
482 }
483
484 static void find_non_local_tags(struct transport *transport,
485                         struct ref **head,
486                         struct ref ***tail)
487 {
488         struct path_list existing_refs = { NULL, 0, 0, 0 };
489         struct path_list new_refs = { NULL, 0, 0, 1 };
490         char *ref_name;
491         int ref_name_len;
492         const unsigned char *ref_sha1;
493         const struct ref *tag_ref;
494         struct ref *rm = NULL;
495         const struct ref *ref;
496
497         for_each_ref(add_existing, &existing_refs);
498         for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
499                 if (prefixcmp(ref->name, "refs/tags"))
500                         continue;
501
502                 ref_name = xstrdup(ref->name);
503                 ref_name_len = strlen(ref_name);
504                 ref_sha1 = ref->old_sha1;
505
506                 if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
507                         ref_name[ref_name_len - 3] = 0;
508                         tag_ref = transport_get_remote_refs(transport);
509                         while (tag_ref) {
510                                 if (!strcmp(tag_ref->name, ref_name)) {
511                                         ref_sha1 = tag_ref->old_sha1;
512                                         break;
513                                 }
514                                 tag_ref = tag_ref->next;
515                         }
516                 }
517
518                 if (!path_list_has_path(&existing_refs, ref_name) &&
519                     !path_list_has_path(&new_refs, ref_name) &&
520                     (has_sha1_file(ref->old_sha1) ||
521                      will_fetch(head, ref->old_sha1))) {
522                         path_list_insert(ref_name, &new_refs);
523
524                         rm = alloc_ref_from_str(ref_name);
525                         rm->peer_ref = alloc_ref_from_str(ref_name);
526                         hashcpy(rm->old_sha1, ref_sha1);
527
528                         **tail = rm;
529                         *tail = &rm->next;
530                 }
531                 free(ref_name);
532         }
533         path_list_clear(&existing_refs, 0);
534         path_list_clear(&new_refs, 0);
535 }
536
537 static int do_fetch(struct transport *transport,
538                     struct refspec *refs, int ref_count)
539 {
540         struct ref *ref_map;
541         struct ref *rm;
542         int autotags = (transport->remote->fetch_tags == 1);
543         if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
544                 tags = TAGS_SET;
545         if (transport->remote->fetch_tags == -1)
546                 tags = TAGS_UNSET;
547
548         if (!transport->get_refs_list || !transport->fetch)
549                 die("Don't know how to fetch from %s", transport->url);
550
551         /* if not appending, truncate FETCH_HEAD */
552         if (!append) {
553                 char *filename = git_path("FETCH_HEAD");
554                 FILE *fp = fopen(filename, "w");
555                 if (!fp)
556                         return error("cannot open %s: %s\n", filename, strerror(errno));
557                 fclose(fp);
558         }
559
560         ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
561
562         for (rm = ref_map; rm; rm = rm->next) {
563                 if (rm->peer_ref)
564                         read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
565         }
566
567         if (tags == TAGS_DEFAULT && autotags)
568                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
569         if (fetch_refs(transport, ref_map)) {
570                 free_refs(ref_map);
571                 return 1;
572         }
573         free_refs(ref_map);
574
575         /* if neither --no-tags nor --tags was specified, do automated tag
576          * following ... */
577         if (tags == TAGS_DEFAULT && autotags) {
578                 struct ref **tail = &ref_map;
579                 ref_map = NULL;
580                 find_non_local_tags(transport, &ref_map, &tail);
581                 if (ref_map) {
582                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
583                         transport_set_option(transport, TRANS_OPT_DEPTH, "0");
584                         fetch_refs(transport, ref_map);
585                 }
586                 free_refs(ref_map);
587         }
588
589         return 0;
590 }
591
592 static void set_option(const char *name, const char *value)
593 {
594         int r = transport_set_option(transport, name, value);
595         if (r < 0)
596                 die("Option \"%s\" value \"%s\" is not valid for %s\n",
597                         name, value, transport->url);
598         if (r > 0)
599                 warning("Option \"%s\" is ignored for %s\n",
600                         name, transport->url);
601 }
602
603 int cmd_fetch(int argc, const char **argv, const char *prefix)
604 {
605         struct remote *remote;
606         int i;
607         static const char **refs = NULL;
608         int ref_nr = 0;
609         int exit_code;
610
611         /* Record the command line for the reflog */
612         strbuf_addstr(&default_rla, "fetch");
613         for (i = 1; i < argc; i++)
614                 strbuf_addf(&default_rla, " %s", argv[i]);
615
616         argc = parse_options(argc, argv,
617                              builtin_fetch_options, builtin_fetch_usage, 0);
618
619         if (argc == 0)
620                 remote = remote_get(NULL);
621         else
622                 remote = remote_get(argv[0]);
623
624         transport = transport_get(remote, remote->url[0]);
625         if (verbose >= 2)
626                 transport->verbose = 1;
627         if (quiet)
628                 transport->verbose = -1;
629         if (upload_pack)
630                 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
631         if (keep)
632                 set_option(TRANS_OPT_KEEP, "yes");
633         if (depth)
634                 set_option(TRANS_OPT_DEPTH, depth);
635
636         if (!transport->url)
637                 die("Where do you want to fetch from today?");
638
639         if (argc > 1) {
640                 int j = 0;
641                 refs = xcalloc(argc + 1, sizeof(const char *));
642                 for (i = 1; i < argc; i++) {
643                         if (!strcmp(argv[i], "tag")) {
644                                 char *ref;
645                                 i++;
646                                 if (i >= argc)
647                                         die("You need to specify a tag name.");
648                                 ref = xmalloc(strlen(argv[i]) * 2 + 22);
649                                 strcpy(ref, "refs/tags/");
650                                 strcat(ref, argv[i]);
651                                 strcat(ref, ":refs/tags/");
652                                 strcat(ref, argv[i]);
653                                 refs[j++] = ref;
654                         } else
655                                 refs[j++] = argv[i];
656                 }
657                 refs[j] = NULL;
658                 ref_nr = j;
659         }
660
661         signal(SIGINT, unlock_pack_on_signal);
662         atexit(unlock_pack);
663         exit_code = do_fetch(transport,
664                         parse_fetch_refspec(ref_nr, refs), ref_nr);
665         transport_disconnect(transport);
666         transport = NULL;
667         return exit_code;
668 }