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
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 struct refspec refspec;
132 refspec.src = "refs/tags/";
133 refspec.dst = "refs/tags/";
134 refspec.pattern = 1;
135 refspec.force = 0;
136 get_fetch_map(remote_refs, &refspec, &tail, 0);
137 }
138 } else {
139 /* Use the defaults */
140 struct remote *remote = transport->remote;
141 struct branch *branch = branch_get(NULL);
142 int has_merge = branch_has_merge_config(branch);
143 if (remote && (remote->fetch_refspec_nr || has_merge)) {
144 for (i = 0; i < remote->fetch_refspec_nr; i++) {
145 get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
146 if (remote->fetch[i].dst &&
147 remote->fetch[i].dst[0])
148 *autotags = 1;
149 if (!i && !has_merge && ref_map &&
150 !remote->fetch[0].pattern)
151 ref_map->merge = 1;
152 }
153 /*
154 * if the remote we're fetching from is the same
155 * as given in branch.<name>.remote, we add the
156 * ref given in branch.<name>.merge, too.
157 */
158 if (has_merge &&
159 !strcmp(branch->remote_name, remote->name))
160 add_merge_config(&ref_map, remote_refs, branch, &tail);
161 } else {
162 ref_map = get_remote_ref(remote_refs, "HEAD");
163 if (!ref_map)
164 die("Couldn't find remote ref HEAD");
165 ref_map->merge = 1;
166 tail = &ref_map->next;
167 }
168 }
169 if (tags == TAGS_DEFAULT && *autotags)
170 find_non_local_tags(transport, &ref_map, &tail);
171 ref_remove_duplicates(ref_map);
172
173 return ref_map;
174}
175
176static int s_update_ref(const char *action,
177 struct ref *ref,
178 int check_old)
179{
180 char msg[1024];
181 char *rla = getenv("GIT_REFLOG_ACTION");
182 static struct ref_lock *lock;
183
184 if (!rla)
185 rla = default_rla.buf;
186 snprintf(msg, sizeof(msg), "%s: %s", rla, action);
187 lock = lock_any_ref_for_update(ref->name,
188 check_old ? ref->old_sha1 : NULL, 0);
189 if (!lock)
190 return 1;
191 if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
192 return 1;
193 return 0;
194}
195
196#define SUMMARY_WIDTH (2 * DEFAULT_ABBREV + 3)
197#define REFCOL_WIDTH 10
198
199static int update_local_ref(struct ref *ref,
200 const char *remote,
201 int verbose,
202 char *display)
203{
204 struct commit *current = NULL, *updated;
205 enum object_type type;
206 struct branch *current_branch = branch_get(NULL);
207 const char *pretty_ref = ref->name + (
208 !prefixcmp(ref->name, "refs/heads/") ? 11 :
209 !prefixcmp(ref->name, "refs/tags/") ? 10 :
210 !prefixcmp(ref->name, "refs/remotes/") ? 13 :
211 0);
212
213 *display = 0;
214 type = sha1_object_info(ref->new_sha1, NULL);
215 if (type < 0)
216 die("object %s not found", sha1_to_hex(ref->new_sha1));
217
218 if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
219 if (verbose)
220 sprintf(display, "= %-*s %-*s -> %s", SUMMARY_WIDTH,
221 "[up to date]", REFCOL_WIDTH, remote,
222 pretty_ref);
223 return 0;
224 }
225
226 if (current_branch &&
227 !strcmp(ref->name, current_branch->name) &&
228 !(update_head_ok || is_bare_repository()) &&
229 !is_null_sha1(ref->old_sha1)) {
230 /*
231 * If this is the head, and it's not okay to update
232 * the head, and the old value of the head isn't empty...
233 */
234 sprintf(display, "! %-*s %-*s -> %s (can't fetch in current branch)",
235 SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
236 pretty_ref);
237 return 1;
238 }
239
240 if (!is_null_sha1(ref->old_sha1) &&
241 !prefixcmp(ref->name, "refs/tags/")) {
242 sprintf(display, "- %-*s %-*s -> %s",
243 SUMMARY_WIDTH, "[tag update]", REFCOL_WIDTH, remote,
244 pretty_ref);
245 return s_update_ref("updating tag", ref, 0);
246 }
247
248 current = lookup_commit_reference_gently(ref->old_sha1, 1);
249 updated = lookup_commit_reference_gently(ref->new_sha1, 1);
250 if (!current || !updated) {
251 const char *msg;
252 const char *what;
253 if (!strncmp(ref->name, "refs/tags/", 10)) {
254 msg = "storing tag";
255 what = "[new tag]";
256 }
257 else {
258 msg = "storing head";
259 what = "[new branch]";
260 }
261
262 sprintf(display, "* %-*s %-*s -> %s", SUMMARY_WIDTH, what,
263 REFCOL_WIDTH, remote, pretty_ref);
264 return s_update_ref(msg, ref, 0);
265 }
266
267 if (in_merge_bases(current, &updated, 1)) {
268 char quickref[83];
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 sprintf(display, " %-*s %-*s -> %s", SUMMARY_WIDTH, quickref,
273 REFCOL_WIDTH, remote, pretty_ref);
274 return s_update_ref("fast forward", ref, 1);
275 } else if (force || ref->force) {
276 char quickref[84];
277 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
278 strcat(quickref, "...");
279 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
280 sprintf(display, "+ %-*s %-*s -> %s (forced update)",
281 SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote, pretty_ref);
282 return s_update_ref("forced-update", ref, 1);
283 } else {
284 sprintf(display, "! %-*s %-*s -> %s (non fast forward)",
285 SUMMARY_WIDTH, "[rejected]", REFCOL_WIDTH, remote,
286 pretty_ref);
287 return 1;
288 }
289}
290
291static int store_updated_refs(const char *url, struct ref *ref_map)
292{
293 FILE *fp;
294 struct commit *commit;
295 int url_len, i, note_len, shown_url = 0;
296 char note[1024];
297 const char *what, *kind;
298 struct ref *rm;
299 char *filename = git_path("FETCH_HEAD");
300
301 fp = fopen(filename, "a");
302 if (!fp)
303 return error("cannot open %s: %s\n", filename, strerror(errno));
304 for (rm = ref_map; rm; rm = rm->next) {
305 struct ref *ref = NULL;
306
307 if (rm->peer_ref) {
308 ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
309 strcpy(ref->name, rm->peer_ref->name);
310 hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
311 hashcpy(ref->new_sha1, rm->old_sha1);
312 ref->force = rm->peer_ref->force;
313 }
314
315 commit = lookup_commit_reference_gently(rm->old_sha1, 1);
316 if (!commit)
317 rm->merge = 0;
318
319 if (!strcmp(rm->name, "HEAD")) {
320 kind = "";
321 what = "";
322 }
323 else if (!prefixcmp(rm->name, "refs/heads/")) {
324 kind = "branch";
325 what = rm->name + 11;
326 }
327 else if (!prefixcmp(rm->name, "refs/tags/")) {
328 kind = "tag";
329 what = rm->name + 10;
330 }
331 else if (!prefixcmp(rm->name, "refs/remotes/")) {
332 kind = "remote branch";
333 what = rm->name + 13;
334 }
335 else {
336 kind = "";
337 what = rm->name;
338 }
339
340 url_len = strlen(url);
341 for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
342 ;
343 url_len = i + 1;
344 if (4 < i && !strncmp(".git", url + i - 3, 4))
345 url_len = i - 3;
346
347 note_len = 0;
348 if (*what) {
349 if (*kind)
350 note_len += sprintf(note + note_len, "%s ",
351 kind);
352 note_len += sprintf(note + note_len, "'%s' of ", what);
353 }
354 note_len += sprintf(note + note_len, "%.*s", url_len, url);
355 fprintf(fp, "%s\t%s\t%s\n",
356 sha1_to_hex(commit ? commit->object.sha1 :
357 rm->old_sha1),
358 rm->merge ? "" : "not-for-merge",
359 note);
360
361 if (ref)
362 update_local_ref(ref, what, verbose, note);
363 else if (verbose)
364 sprintf(note, "* %-*s %-*s -> FETCH_HEAD",
365 SUMMARY_WIDTH, *kind ? kind : "branch",
366 REFCOL_WIDTH, *what ? what : "HEAD");
367 else
368 *note = '\0';
369 if (*note) {
370 if (!shown_url) {
371 fprintf(stderr, "From %.*s\n",
372 url_len, url);
373 shown_url = 1;
374 }
375 fprintf(stderr, " %s\n", note);
376 }
377 }
378 fclose(fp);
379 return 0;
380}
381
382/*
383 * We would want to bypass the object transfer altogether if
384 * everything we are going to fetch already exists and connected
385 * locally.
386 *
387 * The refs we are going to fetch are in to_fetch (nr_heads in
388 * total). If running
389 *
390 * $ git-rev-list --objects to_fetch[0] to_fetch[1] ... --not --all
391 *
392 * does not error out, that means everything reachable from the
393 * refs we are going to fetch exists and is connected to some of
394 * our existing refs.
395 */
396static int quickfetch(struct ref *ref_map)
397{
398 struct child_process revlist;
399 struct ref *ref;
400 char **argv;
401 int i, err;
402
403 /*
404 * If we are deepening a shallow clone we already have these
405 * objects reachable. Running rev-list here will return with
406 * a good (0) exit status and we'll bypass the fetch that we
407 * really need to perform. Claiming failure now will ensure
408 * we perform the network exchange to deepen our history.
409 */
410 if (depth)
411 return -1;
412
413 for (i = 0, ref = ref_map; ref; ref = ref->next)
414 i++;
415 if (!i)
416 return 0;
417
418 argv = xmalloc(sizeof(*argv) * (i + 6));
419 i = 0;
420 argv[i++] = xstrdup("rev-list");
421 argv[i++] = xstrdup("--quiet");
422 argv[i++] = xstrdup("--objects");
423 for (ref = ref_map; ref; ref = ref->next)
424 argv[i++] = xstrdup(sha1_to_hex(ref->old_sha1));
425 argv[i++] = xstrdup("--not");
426 argv[i++] = xstrdup("--all");
427 argv[i++] = NULL;
428
429 memset(&revlist, 0, sizeof(revlist));
430 revlist.argv = (const char**)argv;
431 revlist.git_cmd = 1;
432 revlist.no_stdin = 1;
433 revlist.no_stdout = 1;
434 revlist.no_stderr = 1;
435 err = run_command(&revlist);
436
437 for (i = 0; argv[i]; i++)
438 free(argv[i]);
439 free(argv);
440 return err;
441}
442
443static int fetch_refs(struct transport *transport, struct ref *ref_map)
444{
445 int ret = quickfetch(ref_map);
446 if (ret)
447 ret = transport_fetch_refs(transport, ref_map);
448 if (!ret)
449 ret |= store_updated_refs(transport->url, ref_map);
450 transport_unlock_pack(transport);
451 return ret;
452}
453
454static int add_existing(const char *refname, const unsigned char *sha1,
455 int flag, void *cbdata)
456{
457 struct path_list *list = (struct path_list *)cbdata;
458 path_list_insert(refname, list);
459 return 0;
460}
461
462static int will_fetch(struct ref **head, const unsigned char *sha1)
463{
464 struct ref *rm = *head;
465 while (rm) {
466 if (!hashcmp(rm->old_sha1, sha1))
467 return 1;
468 rm = rm->next;
469 }
470 return 0;
471}
472
473static void find_non_local_tags(struct transport *transport,
474 struct ref **head,
475 struct ref ***tail)
476{
477 struct path_list existing_refs = { NULL, 0, 0, 0 };
478 struct path_list new_refs = { NULL, 0, 0, 1 };
479 char *ref_name;
480 int ref_name_len;
481 const unsigned char *ref_sha1;
482 const struct ref *tag_ref;
483 struct ref *rm = NULL;
484 const struct ref *ref;
485
486 for_each_ref(add_existing, &existing_refs);
487 for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
488 if (prefixcmp(ref->name, "refs/tags"))
489 continue;
490
491 ref_name = xstrdup(ref->name);
492 ref_name_len = strlen(ref_name);
493 ref_sha1 = ref->old_sha1;
494
495 if (!strcmp(ref_name + ref_name_len - 3, "^{}")) {
496 ref_name[ref_name_len - 3] = 0;
497 tag_ref = transport_get_remote_refs(transport);
498 while (tag_ref) {
499 if (!strcmp(tag_ref->name, ref_name)) {
500 ref_sha1 = tag_ref->old_sha1;
501 break;
502 }
503 tag_ref = tag_ref->next;
504 }
505 }
506
507 if (!path_list_has_path(&existing_refs, ref_name) &&
508 !path_list_has_path(&new_refs, ref_name) &&
509 (has_sha1_file(ref->old_sha1) ||
510 will_fetch(head, ref->old_sha1))) {
511 path_list_insert(ref_name, &new_refs);
512
513 rm = alloc_ref(strlen(ref_name) + 1);
514 strcpy(rm->name, ref_name);
515 rm->peer_ref = alloc_ref(strlen(ref_name) + 1);
516 strcpy(rm->peer_ref->name, ref_name);
517 hashcpy(rm->old_sha1, ref_sha1);
518
519 **tail = rm;
520 *tail = &rm->next;
521 }
522 free(ref_name);
523 }
524 path_list_clear(&existing_refs, 0);
525 path_list_clear(&new_refs, 0);
526}
527
528static int do_fetch(struct transport *transport,
529 struct refspec *refs, int ref_count)
530{
531 struct ref *ref_map;
532 struct ref *rm;
533 int autotags = (transport->remote->fetch_tags == 1);
534 if (transport->remote->fetch_tags == 2 && tags != TAGS_UNSET)
535 tags = TAGS_SET;
536 if (transport->remote->fetch_tags == -1)
537 tags = TAGS_UNSET;
538
539 if (!transport->get_refs_list || !transport->fetch)
540 die("Don't know how to fetch from %s", transport->url);
541
542 /* if not appending, truncate FETCH_HEAD */
543 if (!append) {
544 char *filename = git_path("FETCH_HEAD");
545 FILE *fp = fopen(filename, "w");
546 if (!fp)
547 return error("cannot open %s: %s\n", filename, strerror(errno));
548 fclose(fp);
549 }
550
551 ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
552
553 for (rm = ref_map; rm; rm = rm->next) {
554 if (rm->peer_ref)
555 read_ref(rm->peer_ref->name, rm->peer_ref->old_sha1);
556 }
557
558 if (tags == TAGS_DEFAULT && autotags)
559 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
560 if (fetch_refs(transport, ref_map)) {
561 free_refs(ref_map);
562 return 1;
563 }
564 free_refs(ref_map);
565
566 /* if neither --no-tags nor --tags was specified, do automated tag
567 * following ... */
568 if (tags == TAGS_DEFAULT && autotags) {
569 struct ref **tail = &ref_map;
570 ref_map = NULL;
571 find_non_local_tags(transport, &ref_map, &tail);
572 if (ref_map) {
573 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
574 transport_set_option(transport, TRANS_OPT_DEPTH, "0");
575 fetch_refs(transport, ref_map);
576 }
577 free_refs(ref_map);
578 }
579
580 return 0;
581}
582
583static void set_option(const char *name, const char *value)
584{
585 int r = transport_set_option(transport, name, value);
586 if (r < 0)
587 die("Option \"%s\" value \"%s\" is not valid for %s\n",
588 name, value, transport->url);
589 if (r > 0)
590 warning("Option \"%s\" is ignored for %s\n",
591 name, transport->url);
592}
593
594int cmd_fetch(int argc, const char **argv, const char *prefix)
595{
596 struct remote *remote;
597 int i;
598 static const char **refs = NULL;
599 int ref_nr = 0;
600 int exit_code;
601
602 /* Record the command line for the reflog */
603 strbuf_addstr(&default_rla, "fetch");
604 for (i = 1; i < argc; i++)
605 strbuf_addf(&default_rla, " %s", argv[i]);
606
607 argc = parse_options(argc, argv,
608 builtin_fetch_options, builtin_fetch_usage, 0);
609
610 if (argc == 0)
611 remote = remote_get(NULL);
612 else
613 remote = remote_get(argv[0]);
614
615 transport = transport_get(remote, remote->url[0]);
616 if (verbose >= 2)
617 transport->verbose = 1;
618 if (quiet)
619 transport->verbose = -1;
620 if (upload_pack)
621 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
622 if (keep)
623 set_option(TRANS_OPT_KEEP, "yes");
624 if (depth)
625 set_option(TRANS_OPT_DEPTH, depth);
626
627 if (!transport->url)
628 die("Where do you want to fetch from today?");
629
630 if (argc > 1) {
631 int j = 0;
632 refs = xcalloc(argc + 1, sizeof(const char *));
633 for (i = 1; i < argc; i++) {
634 if (!strcmp(argv[i], "tag")) {
635 char *ref;
636 i++;
637 if (i >= argc)
638 die("You need to specify a tag name.");
639 ref = xmalloc(strlen(argv[i]) * 2 + 22);
640 strcpy(ref, "refs/tags/");
641 strcat(ref, argv[i]);
642 strcat(ref, ":refs/tags/");
643 strcat(ref, argv[i]);
644 refs[j++] = ref;
645 } else
646 refs[j++] = argv[i];
647 }
648 refs[j] = NULL;
649 ref_nr = j;
650 }
651
652 signal(SIGINT, unlock_pack_on_signal);
653 atexit(unlock_pack);
654 exit_code = do_fetch(transport,
655 parse_fetch_refspec(ref_nr, refs), ref_nr);
656 transport_disconnect(transport);
657 transport = NULL;
658 return exit_code;
659}