edc78612289c5bd774e18fe5f8e1b9ea80378a5f
[git/git.git] / upload-pack.c
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"
12 #include "run-command.h"
13
14 static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=nn] <dir>";
15
16 /* bits #0..7 in revision.h, #8..10 in commit.c */
17 #define THEY_HAVE (1u << 11)
18 #define OUR_REF (1u << 12)
19 #define WANTED (1u << 13)
20 #define COMMON_KNOWN (1u << 14)
21 #define REACHABLE (1u << 15)
22
23 #define SHALLOW (1u << 16)
24 #define NOT_SHALLOW (1u << 17)
25 #define CLIENT_SHALLOW (1u << 18)
26
27 static unsigned long oldest_have;
28
29 static int multi_ack, nr_our_refs;
30 static int use_thin_pack, use_ofs_delta, use_include_tag;
31 static int no_progress;
32 static struct object_array have_obj;
33 static struct object_array want_obj;
34 static unsigned int timeout;
35 /* 0 for no sideband,
36 * otherwise maximum packet size (up to 65520 bytes).
37 */
38 static int use_sideband;
39 static int debug_fd;
40
41 static void reset_timeout(void)
42 {
43 alarm(timeout);
44 }
45
46 static int strip(char *line, int len)
47 {
48 if (len && line[len-1] == '\n')
49 line[--len] = 0;
50 return len;
51 }
52
53 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
54 {
55 if (use_sideband)
56 return send_sideband(1, fd, data, sz, use_sideband);
57 if (fd == 3)
58 /* emergency quit */
59 fd = 2;
60 if (fd == 2) {
61 /* XXX: are we happy to lose stuff here? */
62 xwrite(fd, data, sz);
63 return sz;
64 }
65 return safe_write(fd, data, sz);
66 }
67
68 static FILE *pack_pipe = NULL;
69 static void show_commit(struct commit *commit, void *data)
70 {
71 if (commit->object.flags & BOUNDARY)
72 fputc('-', pack_pipe);
73 if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0)
74 die("broken output pipe");
75 fputc('\n', pack_pipe);
76 fflush(pack_pipe);
77 free(commit->buffer);
78 commit->buffer = NULL;
79 }
80
81 static void show_object(struct object *obj, const struct name_path *path, const char *component)
82 {
83 /* An object with name "foo\n0000000..." can be used to
84 * confuse downstream git-pack-objects very badly.
85 */
86 const char *name = path_name(path, component);
87 const char *ep = strchr(name, '\n');
88 if (ep) {
89 fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(obj->sha1),
90 (int) (ep - name),
91 name);
92 }
93 else
94 fprintf(pack_pipe, "%s %s\n",
95 sha1_to_hex(obj->sha1), name);
96 free((char *)name);
97 }
98
99 static void show_edge(struct commit *commit)
100 {
101 fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1));
102 }
103
104 static int do_rev_list(int fd, void *create_full_pack)
105 {
106 int i;
107 struct rev_info revs;
108
109 pack_pipe = fdopen(fd, "w");
110 if (create_full_pack)
111 use_thin_pack = 0; /* no point doing it */
112 init_revisions(&revs, NULL);
113 revs.tag_objects = 1;
114 revs.tree_objects = 1;
115 revs.blob_objects = 1;
116 if (use_thin_pack)
117 revs.edge_hint = 1;
118
119 if (create_full_pack) {
120 const char *args[] = {"rev-list", "--all", NULL};
121 setup_revisions(2, args, &revs, NULL);
122 } else {
123 for (i = 0; i < want_obj.nr; i++) {
124 struct object *o = want_obj.objects[i].item;
125 /* why??? */
126 o->flags &= ~UNINTERESTING;
127 add_pending_object(&revs, o, NULL);
128 }
129 for (i = 0; i < have_obj.nr; i++) {
130 struct object *o = have_obj.objects[i].item;
131 o->flags |= UNINTERESTING;
132 add_pending_object(&revs, o, NULL);
133 }
134 setup_revisions(0, NULL, &revs, NULL);
135 }
136 if (prepare_revision_walk(&revs))
137 die("revision walk setup failed");
138 mark_edges_uninteresting(revs.commits, &revs, show_edge);
139 traverse_commit_list(&revs, show_commit, show_object, NULL);
140 fflush(pack_pipe);
141 fclose(pack_pipe);
142 return 0;
143 }
144
145 static void create_pack_file(void)
146 {
147 struct async rev_list;
148 struct child_process pack_objects;
149 int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
150 char data[8193], progress[128];
151 char abort_msg[] = "aborting due to possible repository "
152 "corruption on the remote side.";
153 int buffered = -1;
154 ssize_t sz;
155 const char *argv[10];
156 int arg = 0;
157
158 rev_list.proc = do_rev_list;
159 /* .data is just a boolean: any non-NULL value will do */
160 rev_list.data = create_full_pack ? &rev_list : NULL;
161 if (start_async(&rev_list))
162 die("git upload-pack: unable to fork git-rev-list");
163
164 argv[arg++] = "pack-objects";
165 argv[arg++] = "--stdout";
166 if (!no_progress)
167 argv[arg++] = "--progress";
168 if (use_ofs_delta)
169 argv[arg++] = "--delta-base-offset";
170 if (use_include_tag)
171 argv[arg++] = "--include-tag";
172 argv[arg++] = NULL;
173
174 memset(&pack_objects, 0, sizeof(pack_objects));
175 pack_objects.in = rev_list.out; /* start_command closes it */
176 pack_objects.out = -1;
177 pack_objects.err = -1;
178 pack_objects.git_cmd = 1;
179 pack_objects.argv = argv;
180
181 if (start_command(&pack_objects))
182 die("git upload-pack: unable to fork git-pack-objects");
183
184 /* We read from pack_objects.err to capture stderr output for
185 * progress bar, and pack_objects.out to capture the pack data.
186 */
187
188 while (1) {
189 struct pollfd pfd[2];
190 int pe, pu, pollsize;
191
192 reset_timeout();
193
194 pollsize = 0;
195 pe = pu = -1;
196
197 if (0 <= pack_objects.out) {
198 pfd[pollsize].fd = pack_objects.out;
199 pfd[pollsize].events = POLLIN;
200 pu = pollsize;
201 pollsize++;
202 }
203 if (0 <= pack_objects.err) {
204 pfd[pollsize].fd = pack_objects.err;
205 pfd[pollsize].events = POLLIN;
206 pe = pollsize;
207 pollsize++;
208 }
209
210 if (!pollsize)
211 break;
212
213 if (poll(pfd, pollsize, -1) < 0) {
214 if (errno != EINTR) {
215 error("poll failed, resuming: %s",
216 strerror(errno));
217 sleep(1);
218 }
219 continue;
220 }
221 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
222 /* Data ready; we keep the last byte to ourselves
223 * in case we detect broken rev-list, so that we
224 * can leave the stream corrupted. This is
225 * unfortunate -- unpack-objects would happily
226 * accept a valid packdata with trailing garbage,
227 * so appending garbage after we pass all the
228 * pack data is not good enough to signal
229 * breakage to downstream.
230 */
231 char *cp = data;
232 ssize_t outsz = 0;
233 if (0 <= buffered) {
234 *cp++ = buffered;
235 outsz++;
236 }
237 sz = xread(pack_objects.out, cp,
238 sizeof(data) - outsz);
239 if (0 < sz)
240 ;
241 else if (sz == 0) {
242 close(pack_objects.out);
243 pack_objects.out = -1;
244 }
245 else
246 goto fail;
247 sz += outsz;
248 if (1 < sz) {
249 buffered = data[sz-1] & 0xFF;
250 sz--;
251 }
252 else
253 buffered = -1;
254 sz = send_client_data(1, data, sz);
255 if (sz < 0)
256 goto fail;
257 }
258 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
259 /* Status ready; we ship that in the side-band
260 * or dump to the standard error.
261 */
262 sz = xread(pack_objects.err, progress,
263 sizeof(progress));
264 if (0 < sz)
265 send_client_data(2, progress, sz);
266 else if (sz == 0) {
267 close(pack_objects.err);
268 pack_objects.err = -1;
269 }
270 else
271 goto fail;
272 }
273 }
274
275 if (finish_command(&pack_objects)) {
276 error("git upload-pack: git-pack-objects died with error.");
277 goto fail;
278 }
279 if (finish_async(&rev_list))
280 goto fail; /* error was already reported */
281
282 /* flush the data */
283 if (0 <= buffered) {
284 data[0] = buffered;
285 sz = send_client_data(1, data, 1);
286 if (sz < 0)
287 goto fail;
288 fprintf(stderr, "flushed.\n");
289 }
290 if (use_sideband)
291 packet_flush(1);
292 return;
293
294 fail:
295 send_client_data(3, abort_msg, sizeof(abort_msg));
296 die("git upload-pack: %s", abort_msg);
297 }
298
299 static int got_sha1(char *hex, unsigned char *sha1)
300 {
301 struct object *o;
302 int we_knew_they_have = 0;
303
304 if (get_sha1_hex(hex, sha1))
305 die("git upload-pack: expected SHA1 object, got '%s'", hex);
306 if (!has_sha1_file(sha1))
307 return -1;
308
309 o = lookup_object(sha1);
310 if (!(o && o->parsed))
311 o = parse_object(sha1);
312 if (!o)
313 die("oops (%s)", sha1_to_hex(sha1));
314 if (o->type == OBJ_COMMIT) {
315 struct commit_list *parents;
316 struct commit *commit = (struct commit *)o;
317 if (o->flags & THEY_HAVE)
318 we_knew_they_have = 1;
319 else
320 o->flags |= THEY_HAVE;
321 if (!oldest_have || (commit->date < oldest_have))
322 oldest_have = commit->date;
323 for (parents = commit->parents;
324 parents;
325 parents = parents->next)
326 parents->item->object.flags |= THEY_HAVE;
327 }
328 if (!we_knew_they_have) {
329 add_object_array(o, NULL, &have_obj);
330 return 1;
331 }
332 return 0;
333 }
334
335 static int reachable(struct commit *want)
336 {
337 struct commit_list *work = NULL;
338
339 insert_by_date(want, &work);
340 while (work) {
341 struct commit_list *list = work->next;
342 struct commit *commit = work->item;
343 free(work);
344 work = list;
345
346 if (commit->object.flags & THEY_HAVE) {
347 want->object.flags |= COMMON_KNOWN;
348 break;
349 }
350 if (!commit->object.parsed)
351 parse_object(commit->object.sha1);
352 if (commit->object.flags & REACHABLE)
353 continue;
354 commit->object.flags |= REACHABLE;
355 if (commit->date < oldest_have)
356 continue;
357 for (list = commit->parents; list; list = list->next) {
358 struct commit *parent = list->item;
359 if (!(parent->object.flags & REACHABLE))
360 insert_by_date(parent, &work);
361 }
362 }
363 want->object.flags |= REACHABLE;
364 clear_commit_marks(want, REACHABLE);
365 free_commit_list(work);
366 return (want->object.flags & COMMON_KNOWN);
367 }
368
369 static int ok_to_give_up(void)
370 {
371 int i;
372
373 if (!have_obj.nr)
374 return 0;
375
376 for (i = 0; i < want_obj.nr; i++) {
377 struct object *want = want_obj.objects[i].item;
378
379 if (want->flags & COMMON_KNOWN)
380 continue;
381 want = deref_tag(want, "a want line", 0);
382 if (!want || want->type != OBJ_COMMIT) {
383 /* no way to tell if this is reachable by
384 * looking at the ancestry chain alone, so
385 * leave a note to ourselves not to worry about
386 * this object anymore.
387 */
388 want_obj.objects[i].item->flags |= COMMON_KNOWN;
389 continue;
390 }
391 if (!reachable((struct commit *)want))
392 return 0;
393 }
394 return 1;
395 }
396
397 static int get_common_commits(void)
398 {
399 static char line[1000];
400 unsigned char sha1[20];
401 char hex[41], last_hex[41];
402
403 save_commit_buffer = 0;
404
405 for(;;) {
406 int len = packet_read_line(0, line, sizeof(line));
407 reset_timeout();
408
409 if (!len) {
410 if (have_obj.nr == 0 || multi_ack)
411 packet_write(1, "NAK\n");
412 continue;
413 }
414 strip(line, len);
415 if (!prefixcmp(line, "have ")) {
416 switch (got_sha1(line+5, sha1)) {
417 case -1: /* they have what we do not */
418 if (multi_ack && ok_to_give_up())
419 packet_write(1, "ACK %s continue\n",
420 sha1_to_hex(sha1));
421 break;
422 default:
423 memcpy(hex, sha1_to_hex(sha1), 41);
424 if (multi_ack) {
425 const char *msg = "ACK %s continue\n";
426 packet_write(1, msg, hex);
427 memcpy(last_hex, hex, 41);
428 }
429 else if (have_obj.nr == 1)
430 packet_write(1, "ACK %s\n", hex);
431 break;
432 }
433 continue;
434 }
435 if (!strcmp(line, "done")) {
436 if (have_obj.nr > 0) {
437 if (multi_ack)
438 packet_write(1, "ACK %s\n", last_hex);
439 return 0;
440 }
441 packet_write(1, "NAK\n");
442 return -1;
443 }
444 die("git upload-pack: expected SHA1 list, got '%s'", line);
445 }
446 }
447
448 static void receive_needs(void)
449 {
450 struct object_array shallows = {0, 0, NULL};
451 static char line[1000];
452 int len, depth = 0;
453
454 if (debug_fd)
455 write_in_full(debug_fd, "#S\n", 3);
456 for (;;) {
457 struct object *o;
458 unsigned char sha1_buf[20];
459 len = packet_read_line(0, line, sizeof(line));
460 reset_timeout();
461 if (!len)
462 break;
463 if (debug_fd)
464 write_in_full(debug_fd, line, len);
465
466 if (!prefixcmp(line, "shallow ")) {
467 unsigned char sha1[20];
468 struct object *object;
469 use_thin_pack = 0;
470 if (get_sha1(line + 8, sha1))
471 die("invalid shallow line: %s", line);
472 object = parse_object(sha1);
473 if (!object)
474 die("did not find object for %s", line);
475 object->flags |= CLIENT_SHALLOW;
476 add_object_array(object, NULL, &shallows);
477 continue;
478 }
479 if (!prefixcmp(line, "deepen ")) {
480 char *end;
481 use_thin_pack = 0;
482 depth = strtol(line + 7, &end, 0);
483 if (end == line + 7 || depth <= 0)
484 die("Invalid deepen: %s", line);
485 continue;
486 }
487 if (prefixcmp(line, "want ") ||
488 get_sha1_hex(line+5, sha1_buf))
489 die("git upload-pack: protocol error, "
490 "expected to get sha, not '%s'", line);
491 if (strstr(line+45, "multi_ack"))
492 multi_ack = 1;
493 if (strstr(line+45, "thin-pack"))
494 use_thin_pack = 1;
495 if (strstr(line+45, "ofs-delta"))
496 use_ofs_delta = 1;
497 if (strstr(line+45, "side-band-64k"))
498 use_sideband = LARGE_PACKET_MAX;
499 else if (strstr(line+45, "side-band"))
500 use_sideband = DEFAULT_PACKET_MAX;
501 if (strstr(line+45, "no-progress"))
502 no_progress = 1;
503 if (strstr(line+45, "include-tag"))
504 use_include_tag = 1;
505
506 /* We have sent all our refs already, and the other end
507 * should have chosen out of them; otherwise they are
508 * asking for nonsense.
509 *
510 * Hmph. We may later want to allow "want" line that
511 * asks for something like "master~10" (symbolic)...
512 * would it make sense? I don't know.
513 */
514 o = lookup_object(sha1_buf);
515 if (!o || !(o->flags & OUR_REF))
516 die("git upload-pack: not our ref %s", line+5);
517 if (!(o->flags & WANTED)) {
518 o->flags |= WANTED;
519 add_object_array(o, NULL, &want_obj);
520 }
521 }
522 if (debug_fd)
523 write_in_full(debug_fd, "#E\n", 3);
524 if (depth == 0 && shallows.nr == 0)
525 return;
526 if (depth > 0) {
527 struct commit_list *result, *backup;
528 int i;
529 backup = result = get_shallow_commits(&want_obj, depth,
530 SHALLOW, NOT_SHALLOW);
531 while (result) {
532 struct object *object = &result->item->object;
533 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
534 packet_write(1, "shallow %s",
535 sha1_to_hex(object->sha1));
536 register_shallow(object->sha1);
537 }
538 result = result->next;
539 }
540 free_commit_list(backup);
541 for (i = 0; i < shallows.nr; i++) {
542 struct object *object = shallows.objects[i].item;
543 if (object->flags & NOT_SHALLOW) {
544 struct commit_list *parents;
545 packet_write(1, "unshallow %s",
546 sha1_to_hex(object->sha1));
547 object->flags &= ~CLIENT_SHALLOW;
548 /* make sure the real parents are parsed */
549 unregister_shallow(object->sha1);
550 object->parsed = 0;
551 if (parse_commit((struct commit *)object))
552 die("invalid commit");
553 parents = ((struct commit *)object)->parents;
554 while (parents) {
555 add_object_array(&parents->item->object,
556 NULL, &want_obj);
557 parents = parents->next;
558 }
559 }
560 /* make sure commit traversal conforms to client */
561 register_shallow(object->sha1);
562 }
563 packet_flush(1);
564 } else
565 if (shallows.nr > 0) {
566 int i;
567 for (i = 0; i < shallows.nr; i++)
568 register_shallow(shallows.objects[i].item->sha1);
569 }
570 free(shallows.objects);
571 }
572
573 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
574 {
575 static const char *capabilities = "multi_ack thin-pack side-band"
576 " side-band-64k ofs-delta shallow no-progress"
577 " include-tag";
578 struct object *o = parse_object(sha1);
579
580 if (!o)
581 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
582
583 if (capabilities)
584 packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
585 0, capabilities);
586 else
587 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
588 capabilities = NULL;
589 if (!(o->flags & OUR_REF)) {
590 o->flags |= OUR_REF;
591 nr_our_refs++;
592 }
593 if (o->type == OBJ_TAG) {
594 o = deref_tag(o, refname, 0);
595 if (o)
596 packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
597 }
598 return 0;
599 }
600
601 static void upload_pack(void)
602 {
603 reset_timeout();
604 head_ref(send_ref, NULL);
605 for_each_ref(send_ref, NULL);
606 packet_flush(1);
607 receive_needs();
608 if (want_obj.nr) {
609 get_common_commits();
610 create_pack_file();
611 }
612 }
613
614 int main(int argc, char **argv)
615 {
616 char *dir;
617 int i;
618 int strict = 0;
619
620 git_extract_argv0_path(argv[0]);
621
622 for (i = 1; i < argc; i++) {
623 char *arg = argv[i];
624
625 if (arg[0] != '-')
626 break;
627 if (!strcmp(arg, "--strict")) {
628 strict = 1;
629 continue;
630 }
631 if (!prefixcmp(arg, "--timeout=")) {
632 timeout = atoi(arg+10);
633 continue;
634 }
635 if (!strcmp(arg, "--")) {
636 i++;
637 break;
638 }
639 }
640
641 if (i != argc-1)
642 usage(upload_pack_usage);
643
644 setup_path();
645
646 dir = argv[i];
647
648 if (!enter_repo(dir, strict))
649 die("'%s' does not appear to be a git repository", dir);
650 if (is_repository_shallow())
651 die("attempt to fetch/clone from a shallow repository");
652 if (getenv("GIT_DEBUG_SEND_PACK"))
653 debug_fd = atoi(getenv("GIT_DEBUG_SEND_PACK"));
654 upload_pack();
655 return 0;
656 }