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
14static const char * const builtin_fetch_usage[] = {
15 "git fetch [options] [<repository> <refspec>...]",
16 NULL
17};
18
19enum {
20 TAGS_UNSET = 0,
21 TAGS_DEFAULT = 1,
22 TAGS_SET = 2
23};
24
25static int append, force, keep, update_head_ok, verbose, quiet;
26static int tags = TAGS_DEFAULT;
27static const char *depth;
28static const char *upload_pack;
29static struct strbuf default_rla = STRBUF_INIT;
30static struct transport *transport;
31
32static 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
53static void unlock_pack(void)
54{
55 if (transport)
56 transport_unlock_pack(transport);
57}
58
59static void unlock_pack_on_signal(int signo)
60{
61 unlock_pack();
62 signal(SIGINT, SIG_DFL);
63 raise(signo);
64}
65
66static 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
106static void find_non_local_tags(struct transport *transport,
107 struct ref **head,
108 struct ref ***tail);
109
110static 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
170static 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
193static 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
297static 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 */
405static 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
452static 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
465static int add_existing(const char *refname, const unsigned char *sha1,
466 int flag, void *cbdata)
467{
468 struct string_list *list = (struct string_list *)cbdata;
469 string_list_insert(refname, list);
470 return 0;
471}
472
473static 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
484static void find_non_local_tags(struct transport *transport,
485 struct ref **head,
486 struct ref ***tail)
487{
488 struct string_list existing_refs = { NULL, 0, 0, 0 };
489 struct string_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 (!string_list_has_string(&existing_refs, ref_name) &&
519 !string_list_has_string(&new_refs, ref_name) &&
520 (has_sha1_file(ref->old_sha1) ||
521 will_fetch(head, ref->old_sha1))) {
522 string_list_insert(ref_name, &new_refs);
523
524 rm = alloc_ref(ref_name);
525 rm->peer_ref = alloc_ref(ref_name);
526 hashcpy(rm->old_sha1, ref_sha1);
527
528 **tail = rm;
529 *tail = &rm->next;
530 }
531 free(ref_name);
532 }
533 string_list_clear(&existing_refs, 0);
534 string_list_clear(&new_refs, 0);
535}
536
537static 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
592static 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
603int 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}