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