git-svn: reduce stat() calls for a backwards compatibility check
[git/dscho.git] / upload-pack.c
blobfe96ef15c43fa6e3f8f947f84ddce3c498e82859
1 #include "cache.h"
2 #include "refs.h"
3 #include "pkt-line.h"
4 #include "sideband.h"
5 #include "tag.h"
6 #include "object.h"
7 #include "commit.h"
8 #include "exec_cmd.h"
9 #include "diff.h"
10 #include "revision.h"
11 #include "list-objects.h"
13 static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
15 /* bits #0..7 in revision.h, #8..10 in commit.c */
16 #define THEY_HAVE (1u << 11)
17 #define OUR_REF (1u << 12)
18 #define WANTED (1u << 13)
19 #define COMMON_KNOWN (1u << 14)
20 #define REACHABLE (1u << 15)
22 #define SHALLOW (1u << 16)
23 #define NOT_SHALLOW (1u << 17)
24 #define CLIENT_SHALLOW (1u << 18)
26 static unsigned long oldest_have;
28 static int multi_ack, nr_our_refs;
29 static int use_thin_pack, use_ofs_delta, no_progress;
30 static struct object_array have_obj;
31 static struct object_array want_obj;
32 static unsigned int timeout;
33 /* 0 for no sideband,
34 * otherwise maximum packet size (up to 65520 bytes).
36 static int use_sideband;
38 static void reset_timeout(void)
40 alarm(timeout);
43 static int strip(char *line, int len)
45 if (len && line[len-1] == '\n')
46 line[--len] = 0;
47 return len;
50 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
52 if (use_sideband)
53 return send_sideband(1, fd, data, sz, use_sideband);
54 if (fd == 3)
55 /* emergency quit */
56 fd = 2;
57 if (fd == 2) {
58 /* XXX: are we happy to lose stuff here? */
59 xwrite(fd, data, sz);
60 return sz;
62 return safe_write(fd, data, sz);
65 static FILE *pack_pipe = NULL;
66 static void show_commit(struct commit *commit)
68 if (commit->object.flags & BOUNDARY)
69 fputc('-', pack_pipe);
70 if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0)
71 die("broken output pipe");
72 fputc('\n', pack_pipe);
73 fflush(pack_pipe);
74 free(commit->buffer);
75 commit->buffer = NULL;
78 static void show_object(struct object_array_entry *p)
80 /* An object with name "foo\n0000000..." can be used to
81 * confuse downstream git-pack-objects very badly.
83 const char *ep = strchr(p->name, '\n');
84 if (ep) {
85 fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(p->item->sha1),
86 (int) (ep - p->name),
87 p->name);
89 else
90 fprintf(pack_pipe, "%s %s\n",
91 sha1_to_hex(p->item->sha1), p->name);
94 static void show_edge(struct commit *commit)
96 fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1));
99 static void create_pack_file(void)
101 /* Pipes between rev-list to pack-objects, pack-objects to us
102 * and pack-objects error stream for progress bar.
104 int lp_pipe[2], pu_pipe[2], pe_pipe[2];
105 pid_t pid_rev_list, pid_pack_objects;
106 int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
107 char data[8193], progress[128];
108 char abort_msg[] = "aborting due to possible repository "
109 "corruption on the remote side.";
110 int buffered = -1;
112 if (pipe(lp_pipe) < 0)
113 die("git-upload-pack: unable to create pipe");
114 pid_rev_list = fork();
115 if (pid_rev_list < 0)
116 die("git-upload-pack: unable to fork git-rev-list");
118 if (!pid_rev_list) {
119 int i;
120 struct rev_info revs;
122 close(lp_pipe[0]);
123 pack_pipe = fdopen(lp_pipe[1], "w");
125 if (create_full_pack)
126 use_thin_pack = 0; /* no point doing it */
127 init_revisions(&revs, NULL);
128 revs.tag_objects = 1;
129 revs.tree_objects = 1;
130 revs.blob_objects = 1;
131 if (use_thin_pack)
132 revs.edge_hint = 1;
134 if (create_full_pack) {
135 const char *args[] = {"rev-list", "--all", NULL};
136 setup_revisions(2, args, &revs, NULL);
137 } else {
138 for (i = 0; i < want_obj.nr; i++) {
139 struct object *o = want_obj.objects[i].item;
140 /* why??? */
141 o->flags &= ~UNINTERESTING;
142 add_pending_object(&revs, o, NULL);
144 for (i = 0; i < have_obj.nr; i++) {
145 struct object *o = have_obj.objects[i].item;
146 o->flags |= UNINTERESTING;
147 add_pending_object(&revs, o, NULL);
149 setup_revisions(0, NULL, &revs, NULL);
151 prepare_revision_walk(&revs);
152 mark_edges_uninteresting(revs.commits, &revs, show_edge);
153 traverse_commit_list(&revs, show_commit, show_object);
154 exit(0);
157 if (pipe(pu_pipe) < 0)
158 die("git-upload-pack: unable to create pipe");
159 if (pipe(pe_pipe) < 0)
160 die("git-upload-pack: unable to create pipe");
161 pid_pack_objects = fork();
162 if (pid_pack_objects < 0) {
163 /* daemon sets things up to ignore TERM */
164 kill(pid_rev_list, SIGKILL);
165 die("git-upload-pack: unable to fork git-pack-objects");
167 if (!pid_pack_objects) {
168 const char *argv[10];
169 int i = 0;
171 dup2(lp_pipe[0], 0);
172 dup2(pu_pipe[1], 1);
173 dup2(pe_pipe[1], 2);
175 close(lp_pipe[0]);
176 close(lp_pipe[1]);
177 close(pu_pipe[0]);
178 close(pu_pipe[1]);
179 close(pe_pipe[0]);
180 close(pe_pipe[1]);
182 argv[i++] = "pack-objects";
183 argv[i++] = "--stdout";
184 if (!no_progress)
185 argv[i++] = "--progress";
186 if (use_ofs_delta)
187 argv[i++] = "--delta-base-offset";
188 argv[i++] = NULL;
190 execv_git_cmd(argv);
191 kill(pid_rev_list, SIGKILL);
192 die("git-upload-pack: unable to exec git-pack-objects");
195 close(lp_pipe[0]);
196 close(lp_pipe[1]);
198 /* We read from pe_pipe[0] to capture stderr output for
199 * progress bar, and pu_pipe[0] to capture the pack data.
201 close(pe_pipe[1]);
202 close(pu_pipe[1]);
204 while (1) {
205 const char *who;
206 struct pollfd pfd[2];
207 pid_t pid;
208 int status;
209 ssize_t sz;
210 int pe, pu, pollsize;
212 reset_timeout();
214 pollsize = 0;
215 pe = pu = -1;
217 if (0 <= pu_pipe[0]) {
218 pfd[pollsize].fd = pu_pipe[0];
219 pfd[pollsize].events = POLLIN;
220 pu = pollsize;
221 pollsize++;
223 if (0 <= pe_pipe[0]) {
224 pfd[pollsize].fd = pe_pipe[0];
225 pfd[pollsize].events = POLLIN;
226 pe = pollsize;
227 pollsize++;
230 if (pollsize) {
231 if (poll(pfd, pollsize, -1) < 0) {
232 if (errno != EINTR) {
233 error("poll failed, resuming: %s",
234 strerror(errno));
235 sleep(1);
237 continue;
239 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
240 /* Data ready; we keep the last byte
241 * to ourselves in case we detect
242 * broken rev-list, so that we can
243 * leave the stream corrupted. This
244 * is unfortunate -- unpack-objects
245 * would happily accept a valid pack
246 * data with trailing garbage, so
247 * appending garbage after we pass all
248 * the pack data is not good enough to
249 * signal breakage to downstream.
251 char *cp = data;
252 ssize_t outsz = 0;
253 if (0 <= buffered) {
254 *cp++ = buffered;
255 outsz++;
257 sz = xread(pu_pipe[0], cp,
258 sizeof(data) - outsz);
259 if (0 < sz)
261 else if (sz == 0) {
262 close(pu_pipe[0]);
263 pu_pipe[0] = -1;
265 else
266 goto fail;
267 sz += outsz;
268 if (1 < sz) {
269 buffered = data[sz-1] & 0xFF;
270 sz--;
272 else
273 buffered = -1;
274 sz = send_client_data(1, data, sz);
275 if (sz < 0)
276 goto fail;
278 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
279 /* Status ready; we ship that in the side-band
280 * or dump to the standard error.
282 sz = xread(pe_pipe[0], progress,
283 sizeof(progress));
284 if (0 < sz)
285 send_client_data(2, progress, sz);
286 else if (sz == 0) {
287 close(pe_pipe[0]);
288 pe_pipe[0] = -1;
290 else
291 goto fail;
295 /* See if the children are still there */
296 if (pid_rev_list || pid_pack_objects) {
297 pid = waitpid(-1, &status, WNOHANG);
298 if (!pid)
299 continue;
300 who = ((pid == pid_rev_list) ? "git-rev-list" :
301 (pid == pid_pack_objects) ? "git-pack-objects" :
302 NULL);
303 if (!who) {
304 if (pid < 0) {
305 error("git-upload-pack: %s",
306 strerror(errno));
307 goto fail;
309 error("git-upload-pack: we weren't "
310 "waiting for %d", pid);
311 continue;
313 if (!WIFEXITED(status) || WEXITSTATUS(status) > 0) {
314 error("git-upload-pack: %s died with error.",
315 who);
316 goto fail;
318 if (pid == pid_rev_list)
319 pid_rev_list = 0;
320 if (pid == pid_pack_objects)
321 pid_pack_objects = 0;
322 if (pid_rev_list || pid_pack_objects)
323 continue;
326 /* both died happily */
327 if (pollsize)
328 continue;
330 /* flush the data */
331 if (0 <= buffered) {
332 data[0] = buffered;
333 sz = send_client_data(1, data, 1);
334 if (sz < 0)
335 goto fail;
336 fprintf(stderr, "flushed.\n");
338 if (use_sideband)
339 packet_flush(1);
340 return;
342 fail:
343 if (pid_pack_objects)
344 kill(pid_pack_objects, SIGKILL);
345 if (pid_rev_list)
346 kill(pid_rev_list, SIGKILL);
347 send_client_data(3, abort_msg, sizeof(abort_msg));
348 die("git-upload-pack: %s", abort_msg);
351 static int got_sha1(char *hex, unsigned char *sha1)
353 struct object *o;
354 int we_knew_they_have = 0;
356 if (get_sha1_hex(hex, sha1))
357 die("git-upload-pack: expected SHA1 object, got '%s'", hex);
358 if (!has_sha1_file(sha1))
359 return -1;
361 o = lookup_object(sha1);
362 if (!(o && o->parsed))
363 o = parse_object(sha1);
364 if (!o)
365 die("oops (%s)", sha1_to_hex(sha1));
366 if (o->type == OBJ_COMMIT) {
367 struct commit_list *parents;
368 struct commit *commit = (struct commit *)o;
369 if (o->flags & THEY_HAVE)
370 we_knew_they_have = 1;
371 else
372 o->flags |= THEY_HAVE;
373 if (!oldest_have || (commit->date < oldest_have))
374 oldest_have = commit->date;
375 for (parents = commit->parents;
376 parents;
377 parents = parents->next)
378 parents->item->object.flags |= THEY_HAVE;
380 if (!we_knew_they_have) {
381 add_object_array(o, NULL, &have_obj);
382 return 1;
384 return 0;
387 static int reachable(struct commit *want)
389 struct commit_list *work = NULL;
391 insert_by_date(want, &work);
392 while (work) {
393 struct commit_list *list = work->next;
394 struct commit *commit = work->item;
395 free(work);
396 work = list;
398 if (commit->object.flags & THEY_HAVE) {
399 want->object.flags |= COMMON_KNOWN;
400 break;
402 if (!commit->object.parsed)
403 parse_object(commit->object.sha1);
404 if (commit->object.flags & REACHABLE)
405 continue;
406 commit->object.flags |= REACHABLE;
407 if (commit->date < oldest_have)
408 continue;
409 for (list = commit->parents; list; list = list->next) {
410 struct commit *parent = list->item;
411 if (!(parent->object.flags & REACHABLE))
412 insert_by_date(parent, &work);
415 want->object.flags |= REACHABLE;
416 clear_commit_marks(want, REACHABLE);
417 free_commit_list(work);
418 return (want->object.flags & COMMON_KNOWN);
421 static int ok_to_give_up(void)
423 int i;
425 if (!have_obj.nr)
426 return 0;
428 for (i = 0; i < want_obj.nr; i++) {
429 struct object *want = want_obj.objects[i].item;
431 if (want->flags & COMMON_KNOWN)
432 continue;
433 want = deref_tag(want, "a want line", 0);
434 if (!want || want->type != OBJ_COMMIT) {
435 /* no way to tell if this is reachable by
436 * looking at the ancestry chain alone, so
437 * leave a note to ourselves not to worry about
438 * this object anymore.
440 want_obj.objects[i].item->flags |= COMMON_KNOWN;
441 continue;
443 if (!reachable((struct commit *)want))
444 return 0;
446 return 1;
449 static int get_common_commits(void)
451 static char line[1000];
452 unsigned char sha1[20];
453 char hex[41], last_hex[41];
454 int len;
456 track_object_refs = 0;
457 save_commit_buffer = 0;
459 for(;;) {
460 len = packet_read_line(0, line, sizeof(line));
461 reset_timeout();
463 if (!len) {
464 if (have_obj.nr == 0 || multi_ack)
465 packet_write(1, "NAK\n");
466 continue;
468 len = strip(line, len);
469 if (!prefixcmp(line, "have ")) {
470 switch (got_sha1(line+5, sha1)) {
471 case -1: /* they have what we do not */
472 if (multi_ack && ok_to_give_up())
473 packet_write(1, "ACK %s continue\n",
474 sha1_to_hex(sha1));
475 break;
476 default:
477 memcpy(hex, sha1_to_hex(sha1), 41);
478 if (multi_ack) {
479 const char *msg = "ACK %s continue\n";
480 packet_write(1, msg, hex);
481 memcpy(last_hex, hex, 41);
483 else if (have_obj.nr == 1)
484 packet_write(1, "ACK %s\n", hex);
485 break;
487 continue;
489 if (!strcmp(line, "done")) {
490 if (have_obj.nr > 0) {
491 if (multi_ack)
492 packet_write(1, "ACK %s\n", last_hex);
493 return 0;
495 packet_write(1, "NAK\n");
496 return -1;
498 die("git-upload-pack: expected SHA1 list, got '%s'", line);
502 static void receive_needs(void)
504 struct object_array shallows = {0, 0, NULL};
505 static char line[1000];
506 int len, depth = 0;
508 for (;;) {
509 struct object *o;
510 unsigned char sha1_buf[20];
511 len = packet_read_line(0, line, sizeof(line));
512 reset_timeout();
513 if (!len)
514 break;
516 if (!prefixcmp(line, "shallow ")) {
517 unsigned char sha1[20];
518 struct object *object;
519 use_thin_pack = 0;
520 if (get_sha1(line + 8, sha1))
521 die("invalid shallow line: %s", line);
522 object = parse_object(sha1);
523 if (!object)
524 die("did not find object for %s", line);
525 object->flags |= CLIENT_SHALLOW;
526 add_object_array(object, NULL, &shallows);
527 continue;
529 if (!prefixcmp(line, "deepen ")) {
530 char *end;
531 use_thin_pack = 0;
532 depth = strtol(line + 7, &end, 0);
533 if (end == line + 7 || depth <= 0)
534 die("Invalid deepen: %s", line);
535 continue;
537 if (prefixcmp(line, "want ") ||
538 get_sha1_hex(line+5, sha1_buf))
539 die("git-upload-pack: protocol error, "
540 "expected to get sha, not '%s'", line);
541 if (strstr(line+45, "multi_ack"))
542 multi_ack = 1;
543 if (strstr(line+45, "thin-pack"))
544 use_thin_pack = 1;
545 if (strstr(line+45, "ofs-delta"))
546 use_ofs_delta = 1;
547 if (strstr(line+45, "side-band-64k"))
548 use_sideband = LARGE_PACKET_MAX;
549 else if (strstr(line+45, "side-band"))
550 use_sideband = DEFAULT_PACKET_MAX;
551 if (strstr(line+45, "no-progress"))
552 no_progress = 1;
554 /* We have sent all our refs already, and the other end
555 * should have chosen out of them; otherwise they are
556 * asking for nonsense.
558 * Hmph. We may later want to allow "want" line that
559 * asks for something like "master~10" (symbolic)...
560 * would it make sense? I don't know.
562 o = lookup_object(sha1_buf);
563 if (!o || !(o->flags & OUR_REF))
564 die("git-upload-pack: not our ref %s", line+5);
565 if (!(o->flags & WANTED)) {
566 o->flags |= WANTED;
567 add_object_array(o, NULL, &want_obj);
570 if (depth == 0 && shallows.nr == 0)
571 return;
572 if (depth > 0) {
573 struct commit_list *result, *backup;
574 int i;
575 backup = result = get_shallow_commits(&want_obj, depth,
576 SHALLOW, NOT_SHALLOW);
577 while (result) {
578 struct object *object = &result->item->object;
579 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
580 packet_write(1, "shallow %s",
581 sha1_to_hex(object->sha1));
582 register_shallow(object->sha1);
584 result = result->next;
586 free_commit_list(backup);
587 for (i = 0; i < shallows.nr; i++) {
588 struct object *object = shallows.objects[i].item;
589 if (object->flags & NOT_SHALLOW) {
590 struct commit_list *parents;
591 packet_write(1, "unshallow %s",
592 sha1_to_hex(object->sha1));
593 object->flags &= ~CLIENT_SHALLOW;
594 /* make sure the real parents are parsed */
595 unregister_shallow(object->sha1);
596 object->parsed = 0;
597 parse_commit((struct commit *)object);
598 parents = ((struct commit *)object)->parents;
599 while (parents) {
600 add_object_array(&parents->item->object,
601 NULL, &want_obj);
602 parents = parents->next;
605 /* make sure commit traversal conforms to client */
606 register_shallow(object->sha1);
608 packet_flush(1);
609 } else
610 if (shallows.nr > 0) {
611 int i;
612 for (i = 0; i < shallows.nr; i++)
613 register_shallow(shallows.objects[i].item->sha1);
615 free(shallows.objects);
618 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
620 static const char *capabilities = "multi_ack thin-pack side-band"
621 " side-band-64k ofs-delta shallow no-progress";
622 struct object *o = parse_object(sha1);
624 if (!o)
625 die("git-upload-pack: cannot find object %s:", sha1_to_hex(sha1));
627 if (capabilities)
628 packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
629 0, capabilities);
630 else
631 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
632 capabilities = NULL;
633 if (!(o->flags & OUR_REF)) {
634 o->flags |= OUR_REF;
635 nr_our_refs++;
637 if (o->type == OBJ_TAG) {
638 o = deref_tag(o, refname, 0);
639 packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
641 return 0;
644 static void upload_pack(void)
646 reset_timeout();
647 head_ref(send_ref, NULL);
648 for_each_ref(send_ref, NULL);
649 packet_flush(1);
650 receive_needs();
651 if (want_obj.nr) {
652 get_common_commits();
653 create_pack_file();
657 int main(int argc, char **argv)
659 char *dir;
660 int i;
661 int strict = 0;
663 for (i = 1; i < argc; i++) {
664 char *arg = argv[i];
666 if (arg[0] != '-')
667 break;
668 if (!strcmp(arg, "--strict")) {
669 strict = 1;
670 continue;
672 if (!prefixcmp(arg, "--timeout=")) {
673 timeout = atoi(arg+10);
674 continue;
676 if (!strcmp(arg, "--")) {
677 i++;
678 break;
682 if (i != argc-1)
683 usage(upload_pack_usage);
684 dir = argv[i];
686 if (!enter_repo(dir, strict))
687 die("'%s': unable to chdir or not a git archive", dir);
688 if (is_repository_shallow())
689 die("attempt to fetch/clone from a shallow repository");
690 upload_pack();
691 return 0;