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