1#include "cache.h"
2#include "refs.h"
3#include "pkt-line.h"
4#include "commit.h"
5#include "tag.h"
6#include "exec_cmd.h"
7#include "pack.h"
8#include "sideband.h"
9static int keep_pack;
11static int transfer_unpack_limit = -1;
12static int fetch_unpack_limit = -1;
13static int unpack_limit = 100;
14static int quiet;
15static int verbose;
16static int fetch_all;
17static int depth;
18static int no_progress;
19static const char fetch_pack_usage[] =
20"git-fetch-pack [--all] [--quiet|-q] [--keep|-k] [--thin] [--upload-pack=<git-upload-pack>] [--depth=<n>] [--no-progress] [-v] [<host>:]<directory> [<refs>...]";
21static const char *uploadpack = "git-upload-pack";
22#define COMPLETE (1U << 0)
24#define COMMON (1U << 1)
25#define COMMON_REF (1U << 2)
26#define SEEN (1U << 3)
27#define POPPED (1U << 4)
28/*
30 * After sending this many "have"s if we do not get any new ACK , we
31 * give up traversing our history.
32 */
33#define MAX_IN_VAIN 256
34static struct commit_list *rev_list;
36static int non_common_revs, multi_ack, use_thin_pack, use_sideband;
37static void rev_list_push(struct commit *commit, int mark)
39{
40 if (!(commit->object.flags & mark)) {
41 commit->object.flags |= mark;
42 if (!(commit->object.parsed))
44 parse_commit(commit);
45 insert_by_date(commit, &rev_list);
47 if (!(commit->object.flags & COMMON))
49 non_common_revs++;
50 }
51}
52static int rev_list_insert_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
54{
55 struct object *o = deref_tag(parse_object(sha1), path, 0);
56 if (o && o->type == OBJ_COMMIT)
58 rev_list_push((struct commit *)o, SEEN);
59 return 0;
61}
62/*
64 This function marks a rev and its ancestors as common.
65 In some cases, it is desirable to mark only the ancestors (for example
66 when only the server does not yet know that they are common).
67*/
68static void mark_common(struct commit *commit,
70 int ancestors_only, int dont_parse)
71{
72 if (commit != NULL && !(commit->object.flags & COMMON)) {
73 struct object *o = (struct object *)commit;
74 if (!ancestors_only)
76 o->flags |= COMMON;
77 if (!(o->flags & SEEN))
79 rev_list_push(commit, SEEN);
80 else {
81 struct commit_list *parents;
82 if (!ancestors_only && !(o->flags & POPPED))
84 non_common_revs--;
85 if (!o->parsed && !dont_parse)
86 parse_commit(commit);
87 for (parents = commit->parents;
89 parents;
90 parents = parents->next)
91 mark_common(parents->item, 0, dont_parse);
92 }
93 }
94}
95/*
97 Get the next rev to send, ignoring the common.
98*/
99static const unsigned char* get_rev(void)
101{
102 struct commit *commit = NULL;
103 while (commit == NULL) {
105 unsigned int mark;
106 struct commit_list* parents;
107 if (rev_list == NULL || non_common_revs == 0)
109 return NULL;
110 commit = rev_list->item;
112 if (!(commit->object.parsed))
113 parse_commit(commit);
114 commit->object.flags |= POPPED;
115 if (!(commit->object.flags & COMMON))
116 non_common_revs--;
117
118 parents = commit->parents;
119 if (commit->object.flags & COMMON) {
121 /* do not send "have", and ignore ancestors */
122 commit = NULL;
123 mark = COMMON | SEEN;
124 } else if (commit->object.flags & COMMON_REF)
125 /* send "have", and ignore ancestors */
126 mark = COMMON | SEEN;
127 else
128 /* send "have", also for its ancestors */
129 mark = SEEN;
130 while (parents) {
132 if (!(parents->item->object.flags & SEEN))
133 rev_list_push(parents->item, mark);
134 if (mark & COMMON)
135 mark_common(parents->item, 1, 0);
136 parents = parents->next;
137 }
138 rev_list = rev_list->next;
140 }
141 return commit->object.sha1;
143}
144static int find_common(int fd[2], unsigned char *result_sha1,
146 struct ref *refs)
147{
148 int fetching;
149 int count = 0, flushes = 0, retval;
150 const unsigned char *sha1;
151 unsigned in_vain = 0;
152 int got_continue = 0;
153 for_each_ref(rev_list_insert_ref, NULL);
155 fetching = 0;
157 for ( ; refs ; refs = refs->next) {
158 unsigned char *remote = refs->old_sha1;
159 struct object *o;
160 /*
162 * If that object is complete (i.e. it is an ancestor of a
163 * local ref), we tell them we have it but do not have to
164 * tell them about its ancestors, which they already know
165 * about.
166 *
167 * We use lookup_object here because we are only
168 * interested in the case we *know* the object is
169 * reachable and we have already scanned it.
170 */
171 if (((o = lookup_object(remote)) != NULL) &&
172 (o->flags & COMPLETE)) {
173 continue;
174 }
175 if (!fetching)
177 packet_write(fd[1], "want %s%s%s%s%s%s%s\n",
178 sha1_to_hex(remote),
179 (multi_ack ? " multi_ack" : ""),
180 (use_sideband == 2 ? " side-band-64k" : ""),
181 (use_sideband == 1 ? " side-band" : ""),
182 (use_thin_pack ? " thin-pack" : ""),
183 (no_progress ? " no-progress" : ""),
184 " ofs-delta");
185 else
186 packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
187 fetching++;
188 }
189 if (is_repository_shallow())
190 write_shallow_commits(fd[1], 1);
191 if (depth > 0)
192 packet_write(fd[1], "deepen %d", depth);
193 packet_flush(fd[1]);
194 if (!fetching)
195 return 1;
196 if (depth > 0) {
198 char line[1024];
199 unsigned char sha1[20];
200 int len;
201 while ((len = packet_read_line(fd[0], line, sizeof(line)))) {
203 if (!prefixcmp(line, "shallow ")) {
204 if (get_sha1_hex(line + 8, sha1))
205 die("invalid shallow line: %s", line);
206 register_shallow(sha1);
207 continue;
208 }
209 if (!prefixcmp(line, "unshallow ")) {
210 if (get_sha1_hex(line + 10, sha1))
211 die("invalid unshallow line: %s", line);
212 if (!lookup_object(sha1))
213 die("object not found: %s", line);
214 /* make sure that it is parsed as shallow */
215 parse_object(sha1);
216 if (unregister_shallow(sha1))
217 die("no shallow found: %s", line);
218 continue;
219 }
220 die("expected shallow/unshallow, got %s", line);
221 }
222 }
223 flushes = 0;
225 retval = -1;
226 while ((sha1 = get_rev())) {
227 packet_write(fd[1], "have %s\n", sha1_to_hex(sha1));
228 if (verbose)
229 fprintf(stderr, "have %s\n", sha1_to_hex(sha1));
230 in_vain++;
231 if (!(31 & ++count)) {
232 int ack;
233 packet_flush(fd[1]);
235 flushes++;
236 /*
238 * We keep one window "ahead" of the other side, and
239 * will wait for an ACK only on the next one
240 */
241 if (count == 32)
242 continue;
243 do {
245 ack = get_ack(fd[0], result_sha1);
246 if (verbose && ack)
247 fprintf(stderr, "got ack %d %s\n", ack,
248 sha1_to_hex(result_sha1));
249 if (ack == 1) {
250 flushes = 0;
251 multi_ack = 0;
252 retval = 0;
253 goto done;
254 } else if (ack == 2) {
255 struct commit *commit =
256 lookup_commit(result_sha1);
257 mark_common(commit, 0, 1);
258 retval = 0;
259 in_vain = 0;
260 got_continue = 1;
261 }
262 } while (ack);
263 flushes--;
264 if (got_continue && MAX_IN_VAIN < in_vain) {
265 if (verbose)
266 fprintf(stderr, "giving up\n");
267 break; /* give up */
268 }
269 }
270 }
271done:
272 packet_write(fd[1], "done\n");
273 if (verbose)
274 fprintf(stderr, "done\n");
275 if (retval != 0) {
276 multi_ack = 0;
277 flushes++;
278 }
279 while (flushes || multi_ack) {
280 int ack = get_ack(fd[0], result_sha1);
281 if (ack) {
282 if (verbose)
283 fprintf(stderr, "got ack (%d) %s\n", ack,
284 sha1_to_hex(result_sha1));
285 if (ack == 1)
286 return 0;
287 multi_ack = 1;
288 continue;
289 }
290 flushes--;
291 }
292 return retval;
293}
294static struct commit_list *complete;
296static int mark_complete(const char *path, const unsigned char *sha1, int flag, void *cb_data)
298{
299 struct object *o = parse_object(sha1);
300 while (o && o->type == OBJ_TAG) {
302 struct tag *t = (struct tag *) o;
303 if (!t->tagged)
304 break; /* broken repository */
305 o->flags |= COMPLETE;
306 o = parse_object(t->tagged->sha1);
307 }
308 if (o && o->type == OBJ_COMMIT) {
309 struct commit *commit = (struct commit *)o;
310 commit->object.flags |= COMPLETE;
311 insert_by_date(commit, &complete);
312 }
313 return 0;
314}
315static void mark_recent_complete_commits(unsigned long cutoff)
317{
318 while (complete && cutoff <= complete->item->date) {
319 if (verbose)
320 fprintf(stderr, "Marking %s as complete\n",
321 sha1_to_hex(complete->item->object.sha1));
322 pop_most_recent_commit(&complete, COMPLETE);
323 }
324}
325static void filter_refs(struct ref **refs, int nr_match, char **match)
327{
328 struct ref **return_refs;
329 struct ref *newlist = NULL;
330 struct ref **newtail = &newlist;
331 struct ref *ref, *next;
332 struct ref *fastarray[32];
333 if (nr_match && !fetch_all) {
335 if (ARRAY_SIZE(fastarray) < nr_match)
336 return_refs = xcalloc(nr_match, sizeof(struct ref *));
337 else {
338 return_refs = fastarray;
339 memset(return_refs, 0, sizeof(struct ref *) * nr_match);
340 }
341 }
342 else
343 return_refs = NULL;
344 for (ref = *refs; ref; ref = next) {
346 next = ref->next;
347 if (!memcmp(ref->name, "refs/", 5) &&
348 check_ref_format(ref->name + 5))
349 ; /* trash */
350 else if (fetch_all &&
351 (!depth || prefixcmp(ref->name, "refs/tags/") )) {
352 *newtail = ref;
353 ref->next = NULL;
354 newtail = &ref->next;
355 continue;
356 }
357 else {
358 int order = path_match(ref->name, nr_match, match);
359 if (order) {
360 return_refs[order-1] = ref;
361 continue; /* we will link it later */
362 }
363 }
364 free(ref);
365 }
366 if (!fetch_all) {
368 int i;
369 for (i = 0; i < nr_match; i++) {
370 ref = return_refs[i];
371 if (ref) {
372 *newtail = ref;
373 ref->next = NULL;
374 newtail = &ref->next;
375 }
376 }
377 if (return_refs != fastarray)
378 free(return_refs);
379 }
380 *refs = newlist;
381}
382static int everything_local(struct ref **refs, int nr_match, char **match)
384{
385 struct ref *ref;
386 int retval;
387 unsigned long cutoff = 0;
388 track_object_refs = 0;
390 save_commit_buffer = 0;
391 for (ref = *refs; ref; ref = ref->next) {
393 struct object *o;
394 o = parse_object(ref->old_sha1);
396 if (!o)
397 continue;
398 /* We already have it -- which may mean that we were
400 * in sync with the other side at some time after
401 * that (it is OK if we guess wrong here).
402 */
403 if (o->type == OBJ_COMMIT) {
404 struct commit *commit = (struct commit *)o;
405 if (!cutoff || cutoff < commit->date)
406 cutoff = commit->date;
407 }
408 }
409 if (!depth) {
411 for_each_ref(mark_complete, NULL);
412 if (cutoff)
413 mark_recent_complete_commits(cutoff);
414 }
415 /*
417 * Mark all complete remote refs as common refs.
418 * Don't mark them common yet; the server has to be told so first.
419 */
420 for (ref = *refs; ref; ref = ref->next) {
421 struct object *o = deref_tag(lookup_object(ref->old_sha1),
422 NULL, 0);
423 if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
425 continue;
426 if (!(o->flags & SEEN)) {
428 rev_list_push((struct commit *)o, COMMON_REF | SEEN);
429 mark_common((struct commit *)o, 1, 1);
431 }
432 }
433 filter_refs(refs, nr_match, match);
435 for (retval = 1, ref = *refs; ref ; ref = ref->next) {
437 const unsigned char *remote = ref->old_sha1;
438 unsigned char local[20];
439 struct object *o;
440 o = lookup_object(remote);
442 if (!o || !(o->flags & COMPLETE)) {
443 retval = 0;
444 if (!verbose)
445 continue;
446 fprintf(stderr,
447 "want %s (%s)\n", sha1_to_hex(remote),
448 ref->name);
449 continue;
450 }
451 hashcpy(ref->new_sha1, local);
453 if (!verbose)
454 continue;
455 fprintf(stderr,
456 "already have %s (%s)\n", sha1_to_hex(remote),
457 ref->name);
458 }
459 return retval;
460}
461static pid_t setup_sideband(int fd[2], int xd[2])
463{
464 pid_t side_pid;
465 if (!use_sideband) {
467 fd[0] = xd[0];
468 fd[1] = xd[1];
469 return 0;
470 }
471 /* xd[] is talking with upload-pack; subprocess reads from
472 * xd[0], spits out band#2 to stderr, and feeds us band#1
473 * through our fd[0].
474 */
475 if (pipe(fd) < 0)
476 die("fetch-pack: unable to set up pipe");
477 side_pid = fork();
478 if (side_pid < 0)
479 die("fetch-pack: unable to fork off sideband demultiplexer");
480 if (!side_pid) {
481 /* subprocess */
482 close(fd[0]);
483 if (xd[0] != xd[1])
484 close(xd[1]);
485 if (recv_sideband("fetch-pack", xd[0], fd[1], 2))
486 exit(1);
487 exit(0);
488 }
489 close(xd[0]);
490 close(fd[1]);
491 fd[1] = xd[1];
492 return side_pid;
493}
494static int get_pack(int xd[2])
496{
497 int status;
498 pid_t pid, side_pid;
499 int fd[2];
500 const char *argv[20];
501 char keep_arg[256];
502 char hdr_arg[256];
503 const char **av;
504 int do_keep = keep_pack;
505 side_pid = setup_sideband(fd, xd);
507 av = argv;
509 *hdr_arg = 0;
510 if (unpack_limit) {
511 struct pack_header header;
512 if (read_pack_header(fd[0], &header))
514 die("protocol error: bad pack header");
515 snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
516 ntohl(header.hdr_version), ntohl(header.hdr_entries));
517 if (ntohl(header.hdr_entries) < unpack_limit)
518 do_keep = 0;
519 else
520 do_keep = 1;
521 }
522 if (do_keep) {
524 *av++ = "index-pack";
525 *av++ = "--stdin";
526 if (!quiet && !no_progress)
527 *av++ = "-v";
528 if (use_thin_pack)
529 *av++ = "--fix-thin";
530 if (keep_pack > 1 || unpack_limit) {
531 int s = sprintf(keep_arg,
532 "--keep=fetch-pack %d on ", getpid());
533 if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
534 strcpy(keep_arg + s, "localhost");
535 *av++ = keep_arg;
536 }
537 }
538 else {
539 *av++ = "unpack-objects";
540 if (quiet)
541 *av++ = "-q";
542 }
543 if (*hdr_arg)
544 *av++ = hdr_arg;
545 *av++ = NULL;
546 pid = fork();
548 if (pid < 0)
549 die("fetch-pack: unable to fork off %s", argv[0]);
550 if (!pid) {
551 dup2(fd[0], 0);
552 close(fd[0]);
553 close(fd[1]);
554 execv_git_cmd(argv);
555 die("%s exec failed", argv[0]);
556 }
557 close(fd[0]);
558 close(fd[1]);
559 while (waitpid(pid, &status, 0) < 0) {
560 if (errno != EINTR)
561 die("waiting for %s: %s", argv[0], strerror(errno));
562 }
563 if (WIFEXITED(status)) {
564 int code = WEXITSTATUS(status);
565 if (code)
566 die("%s died with error code %d", argv[0], code);
567 return 0;
568 }
569 if (WIFSIGNALED(status)) {
570 int sig = WTERMSIG(status);
571 die("%s died of signal %d", argv[0], sig);
572 }
573 die("%s died of unnatural causes %d", argv[0], status);
574}
575static int fetch_pack(int fd[2], int nr_match, char **match)
577{
578 struct ref *ref;
579 unsigned char sha1[20];
580 get_remote_heads(fd[0], &ref, 0, NULL, 0);
582 if (is_repository_shallow() && !server_supports("shallow"))
583 die("Server does not support shallow clients");
584 if (server_supports("multi_ack")) {
585 if (verbose)
586 fprintf(stderr, "Server supports multi_ack\n");
587 multi_ack = 1;
588 }
589 if (server_supports("side-band-64k")) {
590 if (verbose)
591 fprintf(stderr, "Server supports side-band-64k\n");
592 use_sideband = 2;
593 }
594 else if (server_supports("side-band")) {
595 if (verbose)
596 fprintf(stderr, "Server supports side-band\n");
597 use_sideband = 1;
598 }
599 if (!ref) {
600 packet_flush(fd[1]);
601 die("no matching remote head");
602 }
603 if (everything_local(&ref, nr_match, match)) {
604 packet_flush(fd[1]);
605 goto all_done;
606 }
607 if (find_common(fd, sha1, ref) < 0)
608 if (keep_pack != 1)
609 /* When cloning, it is not unusual to have
610 * no common commit.
611 */
612 fprintf(stderr, "warning: no common commits\n");
613 if (get_pack(fd))
615 die("git-fetch-pack: fetch failed.");
616 all_done:
618 while (ref) {
619 printf("%s %s\n",
620 sha1_to_hex(ref->old_sha1), ref->name);
621 ref = ref->next;
622 }
623 return 0;
624}
625static int remove_duplicates(int nr_heads, char **heads)
627{
628 int src, dst;
629 for (src = dst = 0; src < nr_heads; src++) {
631 /* If heads[src] is different from any of
632 * heads[0..dst], push it in.
633 */
634 int i;
635 for (i = 0; i < dst; i++) {
636 if (!strcmp(heads[i], heads[src]))
637 break;
638 }
639 if (i < dst)
640 continue;
641 if (src != dst)
642 heads[dst] = heads[src];
643 dst++;
644 }
645 heads[dst] = 0;
646 return dst;
647}
648static int fetch_pack_config(const char *var, const char *value)
650{
651 if (strcmp(var, "fetch.unpacklimit") == 0) {
652 fetch_unpack_limit = git_config_int(var, value);
653 return 0;
654 }
655 if (strcmp(var, "transfer.unpacklimit") == 0) {
657 transfer_unpack_limit = git_config_int(var, value);
658 return 0;
659 }
660 return git_default_config(var, value);
662}
663static struct lock_file lock;
665int main(int argc, char **argv)
667{
668 int i, ret, nr_heads;
669 char *dest = NULL, **heads;
670 int fd[2];
671 pid_t pid;
672 struct stat st;
673 setup_git_directory();
675 git_config(fetch_pack_config);
676 if (0 <= transfer_unpack_limit)
678 unpack_limit = transfer_unpack_limit;
679 else if (0 <= fetch_unpack_limit)
680 unpack_limit = fetch_unpack_limit;
681 nr_heads = 0;
683 heads = NULL;
684 for (i = 1; i < argc; i++) {
685 char *arg = argv[i];
686 if (*arg == '-') {
688 if (!prefixcmp(arg, "--upload-pack=")) {
689 uploadpack = arg + 14;
690 continue;
691 }
692 if (!prefixcmp(arg, "--exec=")) {
693 uploadpack = arg + 7;
694 continue;
695 }
696 if (!strcmp("--quiet", arg) || !strcmp("-q", arg)) {
697 quiet = 1;
698 continue;
699 }
700 if (!strcmp("--keep", arg) || !strcmp("-k", arg)) {
701 keep_pack++;
702 unpack_limit = 0;
703 continue;
704 }
705 if (!strcmp("--thin", arg)) {
706 use_thin_pack = 1;
707 continue;
708 }
709 if (!strcmp("--all", arg)) {
710 fetch_all = 1;
711 continue;
712 }
713 if (!strcmp("-v", arg)) {
714 verbose = 1;
715 continue;
716 }
717 if (!prefixcmp(arg, "--depth=")) {
718 depth = strtol(arg + 8, NULL, 0);
719 if (stat(git_path("shallow"), &st))
720 st.st_mtime = 0;
721 continue;
722 }
723 if (!strcmp("--no-progress", arg)) {
724 no_progress = 1;
725 continue;
726 }
727 usage(fetch_pack_usage);
728 }
729 dest = arg;
730 heads = argv + i + 1;
731 nr_heads = argc - i - 1;
732 break;
733 }
734 if (!dest)
735 usage(fetch_pack_usage);
736 pid = git_connect(fd, dest, uploadpack);
737 if (pid < 0)
738 return 1;
739 if (heads && nr_heads)
740 nr_heads = remove_duplicates(nr_heads, heads);
741 ret = fetch_pack(fd, nr_heads, heads);
742 close(fd[0]);
743 close(fd[1]);
744 ret |= finish_connect(pid);
745 if (!ret && nr_heads) {
747 /* If the heads to pull were given, we should have
748 * consumed all of them by matching the remote.
749 * Otherwise, 'git-fetch remote no-such-ref' would
750 * silently succeed without issuing an error.
751 */
752 for (i = 0; i < nr_heads; i++)
753 if (heads[i] && heads[i][0]) {
754 error("no such remote ref %s", heads[i]);
755 ret = 1;
756 }
757 }
758 if (!ret && depth > 0) {
760 struct cache_time mtime;
761 char *shallow = git_path("shallow");
762 int fd;
763 mtime.sec = st.st_mtime;
765#ifdef USE_NSEC
766 mtime.usec = st.st_mtim.usec;
767#endif
768 if (stat(shallow, &st)) {
769 if (mtime.sec)
770 die("shallow file was removed during fetch");
771 } else if (st.st_mtime != mtime.sec
772#ifdef USE_NSEC
773 || st.st_mtim.usec != mtime.usec
774#endif
775 )
776 die("shallow file was changed during fetch");
777 fd = hold_lock_file_for_update(&lock, shallow, 1);
779 if (!write_shallow_commits(fd, 0)) {
780 unlink(shallow);
781 rollback_lock_file(&lock);
782 } else {
783 close(fd);
784 commit_lock_file(&lock);
785 }
786 }
787 return !!ret;
789}