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
14static 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
27static unsigned long oldest_have;
28
29static int multi_ack, nr_our_refs;
30static int use_thin_pack, use_ofs_delta, use_include_tag;
31static int no_progress, daemon_mode;
32static int shallow_nr;
33static struct object_array have_obj;
34static struct object_array want_obj;
35static unsigned int timeout;
36/* 0 for no sideband,
37 * otherwise maximum packet size (up to 65520 bytes).
38 */
39static int use_sideband;
40static int debug_fd;
41
42static void reset_timeout(void)
43{
44 alarm(timeout);
45}
46
47static int strip(char *line, int len)
48{
49 if (len && line[len-1] == '\n')
50 line[--len] = 0;
51 return len;
52}
53
54static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
55{
56 if (use_sideband)
57 return send_sideband(1, fd, data, sz, use_sideband);
58 if (fd == 3)
59 /* emergency quit */
60 fd = 2;
61 if (fd == 2) {
62 /* XXX: are we happy to lose stuff here? */
63 xwrite(fd, data, sz);
64 return sz;
65 }
66 return safe_write(fd, data, sz);
67}
68
69static FILE *pack_pipe = NULL;
70static void show_commit(struct commit *commit, void *data)
71{
72 if (commit->object.flags & BOUNDARY)
73 fputc('-', pack_pipe);
74 if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0)
75 die("broken output pipe");
76 fputc('\n', pack_pipe);
77 fflush(pack_pipe);
78 free(commit->buffer);
79 commit->buffer = NULL;
80}
81
82static void show_object(struct object *obj, const struct name_path *path, const char *component)
83{
84 /* An object with name "foo\n0000000..." can be used to
85 * confuse downstream git-pack-objects very badly.
86 */
87 const char *name = path_name(path, component);
88 const char *ep = strchr(name, '\n');
89 if (ep) {
90 fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(obj->sha1),
91 (int) (ep - name),
92 name);
93 }
94 else
95 fprintf(pack_pipe, "%s %s\n",
96 sha1_to_hex(obj->sha1), name);
97 free((char *)name);
98}
99
100static void show_edge(struct commit *commit)
101{
102 fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1));
103}
104
105static int do_rev_list(int fd, void *create_full_pack)
106{
107 int i;
108 struct rev_info revs;
109
110 pack_pipe = fdopen(fd, "w");
111 init_revisions(&revs, NULL);
112 revs.tag_objects = 1;
113 revs.tree_objects = 1;
114 revs.blob_objects = 1;
115 if (use_thin_pack)
116 revs.edge_hint = 1;
117
118 if (create_full_pack) {
119 const char *args[] = {"rev-list", "--all", NULL};
120 setup_revisions(2, args, &revs, NULL);
121 } else {
122 for (i = 0; i < want_obj.nr; i++) {
123 struct object *o = want_obj.objects[i].item;
124 /* why??? */
125 o->flags &= ~UNINTERESTING;
126 add_pending_object(&revs, o, NULL);
127 }
128 for (i = 0; i < have_obj.nr; i++) {
129 struct object *o = have_obj.objects[i].item;
130 o->flags |= UNINTERESTING;
131 add_pending_object(&revs, o, NULL);
132 }
133 setup_revisions(0, NULL, &revs, NULL);
134 }
135 if (prepare_revision_walk(&revs))
136 die("revision walk setup failed");
137 mark_edges_uninteresting(revs.commits, &revs, show_edge);
138 traverse_commit_list(&revs, show_commit, show_object, NULL);
139 fflush(pack_pipe);
140 fclose(pack_pipe);
141 return 0;
142}
143
144static void create_pack_file(void)
145{
146 struct async rev_list;
147 struct child_process pack_objects;
148 int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
149 char data[8193], progress[128];
150 char abort_msg[] = "aborting due to possible repository "
151 "corruption on the remote side.";
152 int buffered = -1;
153 ssize_t sz;
154 const char *argv[10];
155 int arg = 0;
156
157 if (shallow_nr) {
158 rev_list.proc = do_rev_list;
159 rev_list.data = 0;
160 if (start_async(&rev_list))
161 die("git upload-pack: unable to fork git-rev-list");
162 argv[arg++] = "pack-objects";
163 } else {
164 argv[arg++] = "pack-objects";
165 argv[arg++] = "--revs";
166 if (create_full_pack)
167 argv[arg++] = "--all";
168 else if (use_thin_pack)
169 argv[arg++] = "--thin";
170 }
171
172 argv[arg++] = "--stdout";
173 if (!no_progress)
174 argv[arg++] = "--progress";
175 if (use_ofs_delta)
176 argv[arg++] = "--delta-base-offset";
177 if (use_include_tag)
178 argv[arg++] = "--include-tag";
179 argv[arg++] = NULL;
180
181 memset(&pack_objects, 0, sizeof(pack_objects));
182 pack_objects.in = shallow_nr ? rev_list.out : -1;
183 pack_objects.out = -1;
184 pack_objects.err = -1;
185 pack_objects.git_cmd = 1;
186 pack_objects.argv = argv;
187
188 if (start_command(&pack_objects))
189 die("git upload-pack: unable to fork git-pack-objects");
190
191 /* pass on revisions we (don't) want */
192 if (!shallow_nr) {
193 FILE *pipe_fd = fdopen(pack_objects.in, "w");
194 if (!create_full_pack) {
195 int i;
196 for (i = 0; i < want_obj.nr; i++)
197 fprintf(pipe_fd, "%s\n", sha1_to_hex(want_obj.objects[i].item->sha1));
198 fprintf(pipe_fd, "--not\n");
199 for (i = 0; i < have_obj.nr; i++)
200 fprintf(pipe_fd, "%s\n", sha1_to_hex(have_obj.objects[i].item->sha1));
201 }
202
203 fprintf(pipe_fd, "\n");
204 fflush(pipe_fd);
205 fclose(pipe_fd);
206 }
207
208
209 /* We read from pack_objects.err to capture stderr output for
210 * progress bar, and pack_objects.out to capture the pack data.
211 */
212
213 while (1) {
214 struct pollfd pfd[2];
215 int pe, pu, pollsize;
216
217 reset_timeout();
218
219 pollsize = 0;
220 pe = pu = -1;
221
222 if (0 <= pack_objects.out) {
223 pfd[pollsize].fd = pack_objects.out;
224 pfd[pollsize].events = POLLIN;
225 pu = pollsize;
226 pollsize++;
227 }
228 if (0 <= pack_objects.err) {
229 pfd[pollsize].fd = pack_objects.err;
230 pfd[pollsize].events = POLLIN;
231 pe = pollsize;
232 pollsize++;
233 }
234
235 if (!pollsize)
236 break;
237
238 if (poll(pfd, pollsize, -1) < 0) {
239 if (errno != EINTR) {
240 error("poll failed, resuming: %s",
241 strerror(errno));
242 sleep(1);
243 }
244 continue;
245 }
246 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
247 /* Data ready; we keep the last byte to ourselves
248 * in case we detect broken rev-list, so that we
249 * can leave the stream corrupted. This is
250 * unfortunate -- unpack-objects would happily
251 * accept a valid packdata with trailing garbage,
252 * so appending garbage after we pass all the
253 * pack data is not good enough to signal
254 * breakage to downstream.
255 */
256 char *cp = data;
257 ssize_t outsz = 0;
258 if (0 <= buffered) {
259 *cp++ = buffered;
260 outsz++;
261 }
262 sz = xread(pack_objects.out, cp,
263 sizeof(data) - outsz);
264 if (0 < sz)
265 ;
266 else if (sz == 0) {
267 close(pack_objects.out);
268 pack_objects.out = -1;
269 }
270 else
271 goto fail;
272 sz += outsz;
273 if (1 < sz) {
274 buffered = data[sz-1] & 0xFF;
275 sz--;
276 }
277 else
278 buffered = -1;
279 sz = send_client_data(1, data, sz);
280 if (sz < 0)
281 goto fail;
282 }
283 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
284 /* Status ready; we ship that in the side-band
285 * or dump to the standard error.
286 */
287 sz = xread(pack_objects.err, progress,
288 sizeof(progress));
289 if (0 < sz)
290 send_client_data(2, progress, sz);
291 else if (sz == 0) {
292 close(pack_objects.err);
293 pack_objects.err = -1;
294 }
295 else
296 goto fail;
297 }
298 }
299
300 if (finish_command(&pack_objects)) {
301 error("git upload-pack: git-pack-objects died with error.");
302 goto fail;
303 }
304 if (shallow_nr && finish_async(&rev_list))
305 goto fail; /* error was already reported */
306
307 /* flush the data */
308 if (0 <= buffered) {
309 data[0] = buffered;
310 sz = send_client_data(1, data, 1);
311 if (sz < 0)
312 goto fail;
313 fprintf(stderr, "flushed.\n");
314 }
315 if (use_sideband)
316 packet_flush(1);
317 return;
318
319 fail:
320 send_client_data(3, abort_msg, sizeof(abort_msg));
321 die("git upload-pack: %s", abort_msg);
322}
323
324static int got_sha1(char *hex, unsigned char *sha1)
325{
326 struct object *o;
327 int we_knew_they_have = 0;
328
329 if (get_sha1_hex(hex, sha1))
330 die("git upload-pack: expected SHA1 object, got '%s'", hex);
331 if (!has_sha1_file(sha1))
332 return -1;
333
334 o = lookup_object(sha1);
335 if (!(o && o->parsed))
336 o = parse_object(sha1);
337 if (!o)
338 die("oops (%s)", sha1_to_hex(sha1));
339 if (o->type == OBJ_COMMIT) {
340 struct commit_list *parents;
341 struct commit *commit = (struct commit *)o;
342 if (o->flags & THEY_HAVE)
343 we_knew_they_have = 1;
344 else
345 o->flags |= THEY_HAVE;
346 if (!oldest_have || (commit->date < oldest_have))
347 oldest_have = commit->date;
348 for (parents = commit->parents;
349 parents;
350 parents = parents->next)
351 parents->item->object.flags |= THEY_HAVE;
352 }
353 if (!we_knew_they_have) {
354 add_object_array(o, NULL, &have_obj);
355 return 1;
356 }
357 return 0;
358}
359
360static int reachable(struct commit *want)
361{
362 struct commit_list *work = NULL;
363
364 insert_by_date(want, &work);
365 while (work) {
366 struct commit_list *list = work->next;
367 struct commit *commit = work->item;
368 free(work);
369 work = list;
370
371 if (commit->object.flags & THEY_HAVE) {
372 want->object.flags |= COMMON_KNOWN;
373 break;
374 }
375 if (!commit->object.parsed)
376 parse_object(commit->object.sha1);
377 if (commit->object.flags & REACHABLE)
378 continue;
379 commit->object.flags |= REACHABLE;
380 if (commit->date < oldest_have)
381 continue;
382 for (list = commit->parents; list; list = list->next) {
383 struct commit *parent = list->item;
384 if (!(parent->object.flags & REACHABLE))
385 insert_by_date(parent, &work);
386 }
387 }
388 want->object.flags |= REACHABLE;
389 clear_commit_marks(want, REACHABLE);
390 free_commit_list(work);
391 return (want->object.flags & COMMON_KNOWN);
392}
393
394static int ok_to_give_up(void)
395{
396 int i;
397
398 if (!have_obj.nr)
399 return 0;
400
401 for (i = 0; i < want_obj.nr; i++) {
402 struct object *want = want_obj.objects[i].item;
403
404 if (want->flags & COMMON_KNOWN)
405 continue;
406 want = deref_tag(want, "a want line", 0);
407 if (!want || want->type != OBJ_COMMIT) {
408 /* no way to tell if this is reachable by
409 * looking at the ancestry chain alone, so
410 * leave a note to ourselves not to worry about
411 * this object anymore.
412 */
413 want_obj.objects[i].item->flags |= COMMON_KNOWN;
414 continue;
415 }
416 if (!reachable((struct commit *)want))
417 return 0;
418 }
419 return 1;
420}
421
422static int get_common_commits(void)
423{
424 static char line[1000];
425 unsigned char sha1[20];
426 char hex[41], last_hex[41];
427
428 save_commit_buffer = 0;
429
430 for(;;) {
431 int len = packet_read_line(0, line, sizeof(line));
432 reset_timeout();
433
434 if (!len) {
435 if (have_obj.nr == 0 || multi_ack)
436 packet_write(1, "NAK\n");
437 continue;
438 }
439 strip(line, len);
440 if (!prefixcmp(line, "have ")) {
441 switch (got_sha1(line+5, sha1)) {
442 case -1: /* they have what we do not */
443 if (multi_ack && ok_to_give_up())
444 packet_write(1, "ACK %s continue\n",
445 sha1_to_hex(sha1));
446 break;
447 default:
448 memcpy(hex, sha1_to_hex(sha1), 41);
449 if (multi_ack) {
450 const char *msg = "ACK %s continue\n";
451 packet_write(1, msg, hex);
452 memcpy(last_hex, hex, 41);
453 }
454 else if (have_obj.nr == 1)
455 packet_write(1, "ACK %s\n", hex);
456 break;
457 }
458 continue;
459 }
460 if (!strcmp(line, "done")) {
461 if (have_obj.nr > 0) {
462 if (multi_ack)
463 packet_write(1, "ACK %s\n", last_hex);
464 return 0;
465 }
466 packet_write(1, "NAK\n");
467 return -1;
468 }
469 die("git upload-pack: expected SHA1 list, got '%s'", line);
470 }
471}
472
473static void receive_needs(void)
474{
475 struct object_array shallows = {0, 0, NULL};
476 static char line[1000];
477 int len, depth = 0;
478
479 shallow_nr = 0;
480 if (debug_fd)
481 write_in_full(debug_fd, "#S\n", 3);
482 for (;;) {
483 struct object *o;
484 unsigned char sha1_buf[20];
485 len = packet_read_line(0, line, sizeof(line));
486 reset_timeout();
487 if (!len)
488 break;
489 if (debug_fd)
490 write_in_full(debug_fd, line, len);
491
492 if (!prefixcmp(line, "shallow ")) {
493 unsigned char sha1[20];
494 struct object *object;
495 use_thin_pack = 0;
496 if (get_sha1(line + 8, sha1))
497 die("invalid shallow line: %s", line);
498 object = parse_object(sha1);
499 if (!object)
500 die("did not find object for %s", line);
501 object->flags |= CLIENT_SHALLOW;
502 add_object_array(object, NULL, &shallows);
503 continue;
504 }
505 if (!prefixcmp(line, "deepen ")) {
506 char *end;
507 use_thin_pack = 0;
508 depth = strtol(line + 7, &end, 0);
509 if (end == line + 7 || depth <= 0)
510 die("Invalid deepen: %s", line);
511 continue;
512 }
513 if (prefixcmp(line, "want ") ||
514 get_sha1_hex(line+5, sha1_buf))
515 die("git upload-pack: protocol error, "
516 "expected to get sha, not '%s'", line);
517 if (strstr(line+45, "multi_ack"))
518 multi_ack = 1;
519 if (strstr(line+45, "thin-pack"))
520 use_thin_pack = 1;
521 if (strstr(line+45, "ofs-delta"))
522 use_ofs_delta = 1;
523 if (strstr(line+45, "side-band-64k"))
524 use_sideband = LARGE_PACKET_MAX;
525 else if (strstr(line+45, "side-band"))
526 use_sideband = DEFAULT_PACKET_MAX;
527 if (strstr(line+45, "no-progress"))
528 no_progress = 1;
529 if (strstr(line+45, "include-tag"))
530 use_include_tag = 1;
531
532 /* We have sent all our refs already, and the other end
533 * should have chosen out of them; otherwise they are
534 * asking for nonsense.
535 *
536 * Hmph. We may later want to allow "want" line that
537 * asks for something like "master~10" (symbolic)...
538 * would it make sense? I don't know.
539 */
540 o = lookup_object(sha1_buf);
541 if (!o || !(o->flags & OUR_REF))
542 die("git upload-pack: not our ref %s", line+5);
543 if (!(o->flags & WANTED)) {
544 o->flags |= WANTED;
545 add_object_array(o, NULL, &want_obj);
546 }
547 }
548 if (debug_fd)
549 write_in_full(debug_fd, "#E\n", 3);
550
551 if (!use_sideband && daemon_mode)
552 no_progress = 1;
553
554 if (depth == 0 && shallows.nr == 0)
555 return;
556 if (depth > 0) {
557 struct commit_list *result, *backup;
558 int i;
559 backup = result = get_shallow_commits(&want_obj, depth,
560 SHALLOW, NOT_SHALLOW);
561 while (result) {
562 struct object *object = &result->item->object;
563 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
564 packet_write(1, "shallow %s",
565 sha1_to_hex(object->sha1));
566 register_shallow(object->sha1);
567 shallow_nr++;
568 }
569 result = result->next;
570 }
571 free_commit_list(backup);
572 for (i = 0; i < shallows.nr; i++) {
573 struct object *object = shallows.objects[i].item;
574 if (object->flags & NOT_SHALLOW) {
575 struct commit_list *parents;
576 packet_write(1, "unshallow %s",
577 sha1_to_hex(object->sha1));
578 object->flags &= ~CLIENT_SHALLOW;
579 /* make sure the real parents are parsed */
580 unregister_shallow(object->sha1);
581 object->parsed = 0;
582 if (parse_commit((struct commit *)object))
583 die("invalid commit");
584 parents = ((struct commit *)object)->parents;
585 while (parents) {
586 add_object_array(&parents->item->object,
587 NULL, &want_obj);
588 parents = parents->next;
589 }
590 }
591 /* make sure commit traversal conforms to client */
592 register_shallow(object->sha1);
593 }
594 packet_flush(1);
595 } else
596 if (shallows.nr > 0) {
597 int i;
598 for (i = 0; i < shallows.nr; i++)
599 register_shallow(shallows.objects[i].item->sha1);
600 }
601
602 shallow_nr += shallows.nr;
603 free(shallows.objects);
604}
605
606static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
607{
608 static const char *capabilities = "multi_ack thin-pack side-band"
609 " side-band-64k ofs-delta shallow no-progress"
610 " include-tag";
611 struct object *o = parse_object(sha1);
612
613 if (!o)
614 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
615
616 if (capabilities)
617 packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
618 0, capabilities);
619 else
620 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
621 capabilities = NULL;
622 if (!(o->flags & OUR_REF)) {
623 o->flags |= OUR_REF;
624 nr_our_refs++;
625 }
626 if (o->type == OBJ_TAG) {
627 o = deref_tag(o, refname, 0);
628 if (o)
629 packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
630 }
631 return 0;
632}
633
634static void upload_pack(void)
635{
636 reset_timeout();
637 head_ref(send_ref, NULL);
638 for_each_ref(send_ref, NULL);
639 packet_flush(1);
640 receive_needs();
641 if (want_obj.nr) {
642 get_common_commits();
643 create_pack_file();
644 }
645}
646
647int main(int argc, char **argv)
648{
649 char *dir;
650 int i;
651 int strict = 0;
652
653 git_extract_argv0_path(argv[0]);
654 read_replace_refs = 0;
655
656 for (i = 1; i < argc; i++) {
657 char *arg = argv[i];
658
659 if (arg[0] != '-')
660 break;
661 if (!strcmp(arg, "--strict")) {
662 strict = 1;
663 continue;
664 }
665 if (!prefixcmp(arg, "--timeout=")) {
666 timeout = atoi(arg+10);
667 daemon_mode = 1;
668 continue;
669 }
670 if (!strcmp(arg, "--")) {
671 i++;
672 break;
673 }
674 }
675
676 if (i != argc-1)
677 usage(upload_pack_usage);
678
679 setup_path();
680
681 dir = argv[i];
682
683 if (!enter_repo(dir, strict))
684 die("'%s' does not appear to be a git repository", dir);
685 if (is_repository_shallow())
686 die("attempt to fetch/clone from a shallow repository");
687 if (getenv("GIT_DEBUG_SEND_PACK"))
688 debug_fd = atoi(getenv("GIT_DEBUG_SEND_PACK"));
689 upload_pack();
690 return 0;
691}