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Date:: Fri Feb 17 16:49:17 2023 UTC
Message:: unbreak gotd build after recent change to got_pack_create
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1 /*
2  * Copyright (c) 2022 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/queue.h>
18 #include <sys/types.h>
19 
20 #include <event.h>
21 #include <errno.h>
22 #include <imsg.h>
23 #include <signal.h>
24 #include <stdlib.h>
25 #include <limits.h>
26 #include <poll.h>
27 #include <sha1.h>
28 #include <siphash.h>
29 #include <stdio.h>
30 #include <string.h>
31 #include <unistd.h>
32 
33 #include "got_error.h"
34 #include "got_cancel.h"
35 #include "got_object.h"
36 #include "got_repository.h"
37 #include "got_reference.h"
38 #include "got_repository_admin.h"
39 
40 #include "got_lib_delta.h"
41 #include "got_lib_object.h"
42 #include "got_lib_object_idset.h"
43 #include "got_lib_sha1.h"
44 #include "got_lib_pack.h"
45 #include "got_lib_ratelimit.h"
46 #include "got_lib_pack_create.h"
47 #include "got_lib_poll.h"
48 
49 #include "log.h"
50 #include "gotd.h"
51 #include "repo_read.h"
52 
53 #ifndef nitems
54 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
55 #endif
56 
57 static struct repo_read {
58 	pid_t pid;
59 	const char *title;
60 	struct got_repository *repo;
61 	int *pack_fds;
62 	int *temp_fds;
63 	int session_fd;
64 	struct gotd_imsgev session_iev;
65 } repo_read;
66 
67 static struct repo_read_client {
68 	uint32_t			 id;
69 	int				 fd;
70 	int				 delta_cache_fd;
71 	int				 report_progress;
72 	int				 pack_pipe;
73 	struct gotd_object_id_array	 want_ids;
74 	struct gotd_object_id_array	 have_ids;
75 } repo_read_client;
76 
77 static volatile sig_atomic_t sigint_received;
78 static volatile sig_atomic_t sigterm_received;
79 
80 static void
81 catch_sigint(int signo)
82 {
83 	sigint_received = 1;
84 }
85 
86 static void
87 catch_sigterm(int signo)
88 {
89 	sigterm_received = 1;
90 }
91 
92 static const struct got_error *
93 check_cancelled(void *arg)
94 {
95 	if (sigint_received || sigterm_received)
96 		return got_error(GOT_ERR_CANCELLED);
97 
98 	return NULL;
99 }
100 
101 static const struct got_error *
102 send_symref(struct got_reference *symref, struct got_object_id *target_id,
103     struct imsgbuf *ibuf)
104 {
105 	const struct got_error *err = NULL;
106 	struct gotd_imsg_symref isymref;
107 	const char *refname = got_ref_get_name(symref);
108 	const char *target = got_ref_get_symref_target(symref);
109 	size_t len;
110 	struct ibuf *wbuf;
111 
112 	memset(&isymref, 0, sizeof(isymref));
113 	isymref.name_len = strlen(refname);
114 	isymref.target_len = strlen(target);
115 	memcpy(isymref.target_id, target_id->sha1, sizeof(isymref.target_id));
116 
117 	len = sizeof(isymref) + isymref.name_len + isymref.target_len;
118 	if (len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
119 		err = got_error(GOT_ERR_NO_SPACE);
120 		goto done;
121 	}
122 
123 	wbuf = imsg_create(ibuf, GOTD_IMSG_SYMREF, 0, 0, len);
124 	if (wbuf == NULL) {
125 		err = got_error_from_errno("imsg_create SYMREF");
126 		goto done;
127 	}
128 
129 	if (imsg_add(wbuf, &isymref, sizeof(isymref)) == -1) {
130 		err = got_error_from_errno("imsg_add SYMREF");
131 		goto done;
132 	}
133 	if (imsg_add(wbuf, refname, isymref.name_len) == -1) {
134 		err = got_error_from_errno("imsg_add SYMREF");
135 		goto done;
136 	}
137 	if (imsg_add(wbuf, target, isymref.target_len) == -1) {
138 		err = got_error_from_errno("imsg_add SYMREF");
139 		goto done;
140 	}
141 
142 	wbuf->fd = -1;
143 	imsg_close(ibuf, wbuf);
144 done:
145 	free(target_id);
146 	return err;
147 }
148 
149 static const struct got_error *
150 send_peeled_tag_ref(struct got_reference *ref, struct got_object *obj,
151     struct imsgbuf *ibuf)
152 {
153 	const struct got_error *err = NULL;
154 	struct got_tag_object *tag;
155 	size_t namelen, len;
156 	char *peeled_refname = NULL;
157 	struct got_object_id *id;
158 	struct ibuf *wbuf;
159 
160 	err = got_object_tag_open(&tag, repo_read.repo, obj);
161 	if (err)
162 		return err;
163 
164 	if (asprintf(&peeled_refname, "%s^{}", got_ref_get_name(ref)) == -1) {
165 		err = got_error_from_errno("asprintf");
166 		goto done;
167 	}
168 
169 	id = got_object_tag_get_object_id(tag);
170 	namelen = strlen(peeled_refname);
171 
172 	len = sizeof(struct gotd_imsg_ref) + namelen;
173 	if (len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
174 		err = got_error(GOT_ERR_NO_SPACE);
175 		goto done;
176 	}
177 
178 	wbuf = imsg_create(ibuf, GOTD_IMSG_REF, PROC_REPO_READ,
179 	    repo_read.pid, len);
180 	if (wbuf == NULL) {
181 		err = got_error_from_errno("imsg_create MREF");
182 		goto done;
183 	}
184 
185 	/* Keep in sync with struct gotd_imsg_ref definition. */
186 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
187 		err = got_error_from_errno("imsg_add REF");
188 		goto done;
189 	}
190 	if (imsg_add(wbuf, &namelen, sizeof(namelen)) == -1) {
191 		err = got_error_from_errno("imsg_add REF");
192 		goto done;
193 	}
194 	if (imsg_add(wbuf, peeled_refname, namelen) == -1) {
195 		err = got_error_from_errno("imsg_add REF");
196 		goto done;
197 	}
198 
199 	wbuf->fd = -1;
200 	imsg_close(ibuf, wbuf);
201 done:
202 	got_object_tag_close(tag);
203 	return err;
204 }
205 
206 static const struct got_error *
207 send_ref(struct got_reference *ref, struct imsgbuf *ibuf)
208 {
209 	const struct got_error *err;
210 	const char *refname = got_ref_get_name(ref);
211 	size_t namelen;
212 	struct got_object_id *id = NULL;
213 	struct got_object *obj = NULL;
214 	size_t len;
215 	struct ibuf *wbuf;
216 
217 	namelen = strlen(refname);
218 
219 	len = sizeof(struct gotd_imsg_ref) + namelen;
220 	if (len > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
221 		return got_error(GOT_ERR_NO_SPACE);
222 
223 	err = got_ref_resolve(&id, repo_read.repo, ref);
224 	if (err)
225 		return err;
226 
227 	wbuf = imsg_create(ibuf, GOTD_IMSG_REF, PROC_REPO_READ,
228 	    repo_read.pid, len);
229 	if (wbuf == NULL) {
230 		err = got_error_from_errno("imsg_create REF");
231 		goto done;
232 	}
233 
234 	/* Keep in sync with struct gotd_imsg_ref definition. */
235 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
236 		return got_error_from_errno("imsg_add REF");
237 	if (imsg_add(wbuf, &namelen, sizeof(namelen)) == -1)
238 		return got_error_from_errno("imsg_add REF");
239 	if (imsg_add(wbuf, refname, namelen) == -1)
240 		return got_error_from_errno("imsg_add REF");
241 
242 	wbuf->fd = -1;
243 	imsg_close(ibuf, wbuf);
244 
245 	err = got_object_open(&obj, repo_read.repo, id);
246 	if (err)
247 		goto done;
248 	if (obj->type == GOT_OBJ_TYPE_TAG)
249 		err = send_peeled_tag_ref(ref, obj, ibuf);
250 done:
251 	if (obj)
252 		got_object_close(obj);
253 	free(id);
254 	return err;
255 }
256 
257 static const struct got_error *
258 list_refs(struct imsg *imsg)
259 {
260 	const struct got_error *err;
261 	struct repo_read_client *client = &repo_read_client;
262 	struct got_reflist_head refs;
263 	struct got_reflist_entry *re;
264 	struct gotd_imsg_list_refs_internal ireq;
265 	size_t datalen;
266 	struct gotd_imsg_reflist irefs;
267 	struct imsgbuf ibuf;
268 	int client_fd = imsg->fd;
269 	struct got_object_id *head_target_id = NULL;
270 
271 	TAILQ_INIT(&refs);
272 
273 	if (client_fd == -1)
274 		return got_error(GOT_ERR_PRIVSEP_NO_FD);
275 
276 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
277 	if (datalen != sizeof(ireq))
278 		return got_error(GOT_ERR_PRIVSEP_LEN);
279 	memcpy(&ireq, imsg->data, sizeof(ireq));
280 
281 	if (ireq.client_id == 0)
282 		return got_error(GOT_ERR_CLIENT_ID);
283 	if (client->id != 0) {
284 		return got_error_msg(GOT_ERR_CLIENT_ID,
285 		    "duplicate list-refs request");
286 	}
287 	client->id = ireq.client_id;
288 	client->fd = client_fd;
289 
290 	imsg_init(&ibuf, client_fd);
291 
292 	err = got_ref_list(&refs, repo_read.repo, "",
293 	    got_ref_cmp_by_name, NULL);
294 	if (err)
295 		return err;
296 
297 	memset(&irefs, 0, sizeof(irefs));
298 	TAILQ_FOREACH(re, &refs, entry) {
299 		struct got_object_id *id;
300 		int obj_type;
301 
302 		if (got_ref_is_symbolic(re->ref)) {
303 			const char *refname = got_ref_get_name(re->ref);
304 			if (strcmp(refname, GOT_REF_HEAD) != 0)
305 				continue;
306 			err = got_ref_resolve(&head_target_id, repo_read.repo,
307 			    re->ref);
308 			if (err) {
309 				if (err->code != GOT_ERR_NOT_REF)
310 					return err;
311 				/*
312 				 * HEAD points to a non-existent branch.
313 				 * Do not advertise it.
314 				 * Matches git-daemon's behaviour.
315 				 */
316 				head_target_id = NULL;
317 				err = NULL;
318 			} else
319 				irefs.nrefs++;
320 			continue;
321 		}
322 
323 		irefs.nrefs++;
324 
325 		/* Account for a peeled tag refs. */
326 		err = got_ref_resolve(&id, repo_read.repo, re->ref);
327 		if (err)
328 			goto done;
329 		err = got_object_get_type(&obj_type, repo_read.repo, id);
330 		free(id);
331 		if (err)
332 			goto done;
333 		if (obj_type == GOT_OBJ_TYPE_TAG)
334 			irefs.nrefs++;
335 	}
336 
337 	if (imsg_compose(&ibuf, GOTD_IMSG_REFLIST, PROC_REPO_READ,
338 	    repo_read.pid, -1, &irefs, sizeof(irefs)) == -1) {
339 		err = got_error_from_errno("imsg_compose REFLIST");
340 		goto done;
341 	}
342 
343 	/*
344 	 * Send the HEAD symref first. In Git-protocol versions < 2
345 	 * the HEAD symref must be announced on the initial line of
346 	 * the server's ref advertisement.
347 	 * For now, we do not advertise symrefs other than HEAD.
348 	 */
349 	TAILQ_FOREACH(re, &refs, entry) {
350 		if (!got_ref_is_symbolic(re->ref) ||
351 		    strcmp(got_ref_get_name(re->ref), GOT_REF_HEAD) != 0 ||
352 		    head_target_id == NULL)
353 			continue;
354 		err = send_symref(re->ref, head_target_id, &ibuf);
355 		if (err)
356 			goto done;
357 		break;
358 	}
359 	TAILQ_FOREACH(re, &refs, entry) {
360 		if (got_ref_is_symbolic(re->ref))
361 			continue;
362 		err = send_ref(re->ref, &ibuf);
363 		if (err)
364 			goto done;
365 	}
366 
367 	err = gotd_imsg_flush(&ibuf);
368 done:
369 	got_ref_list_free(&refs);
370 	imsg_clear(&ibuf);
371 	return err;
372 }
373 
374 static const struct got_error *
375 record_object_id(struct gotd_object_id_array *array, struct got_object_id *id)
376 {
377 	const size_t alloc_chunksz = 256;
378 
379 	if (array->ids == NULL) {
380 		array->ids = reallocarray(NULL, alloc_chunksz,
381 		    sizeof(*array->ids));
382 		if (array->ids == NULL)
383 			return got_error_from_errno("reallocarray");
384 		array->nalloc = alloc_chunksz;
385 		array->nids = 0;
386 	} else if (array->nalloc <= array->nids) {
387 		struct got_object_id **new;
388 		new = recallocarray(array->ids, array->nalloc,
389 		    array->nalloc + alloc_chunksz, sizeof(*new));
390 		if (new == NULL)
391 			return got_error_from_errno("recallocarray");
392 		array->ids = new;
393 		array->nalloc += alloc_chunksz;
394 	}
395 
396 	array->ids[array->nids] = got_object_id_dup(id);
397 	if (array->ids[array->nids] == NULL)
398 		return got_error_from_errno("got_object_id_dup");
399 	array->nids++;
400 	return NULL;
401 }
402 
403 static void
404 free_object_ids(struct gotd_object_id_array *array)
405 {
406 	size_t i;
407 
408 	for (i = 0; i < array->nids; i++)
409 		free(array->ids[i]);
410 	free(array->ids);
411 
412 	array->ids = NULL;
413 	array->nalloc = 0;
414 	array->nids = 0;
415 }
416 
417 static const struct got_error *
418 recv_want(struct imsg *imsg)
419 {
420 	const struct got_error *err;
421 	struct repo_read_client *client = &repo_read_client;
422 	struct gotd_imsg_want iwant;
423 	size_t datalen;
424 	char hex[SHA1_DIGEST_STRING_LENGTH];
425 	struct got_object_id id;
426 	int obj_type;
427 	struct imsgbuf ibuf;
428 
429 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
430 	if (datalen != sizeof(iwant))
431 		return got_error(GOT_ERR_PRIVSEP_LEN);
432 	memcpy(&iwant, imsg->data, sizeof(iwant));
433 
434 	memset(&id, 0, sizeof(id));
435 	memcpy(id.sha1, iwant.object_id, SHA1_DIGEST_LENGTH);
436 
437 	if (log_getverbose() > 0 &&
438 	    got_sha1_digest_to_str(id.sha1, hex, sizeof(hex)))
439 		log_debug("client wants %s", hex);
440 
441 	imsg_init(&ibuf, client->fd);
442 
443 	err = got_object_get_type(&obj_type, repo_read.repo, &id);
444 	if (err)
445 		return err;
446 
447 	if (obj_type != GOT_OBJ_TYPE_COMMIT &&
448 	    obj_type != GOT_OBJ_TYPE_TAG)
449 		return got_error(GOT_ERR_OBJ_TYPE);
450 
451 	err = record_object_id(&client->want_ids, &id);
452 	if (err)
453 		return err;
454 
455 	gotd_imsg_send_ack(&id, &ibuf, PROC_REPO_READ, repo_read.pid);
456 	imsg_clear(&ibuf);
457 	return err;
458 }
459 
460 static const struct got_error *
461 recv_have(struct imsg *imsg)
462 {
463 	const struct got_error *err;
464 	struct repo_read_client *client = &repo_read_client;
465 	struct gotd_imsg_have ihave;
466 	size_t datalen;
467 	char hex[SHA1_DIGEST_STRING_LENGTH];
468 	struct got_object_id id;
469 	int obj_type;
470 	struct imsgbuf ibuf;
471 
472 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
473 	if (datalen != sizeof(ihave))
474 		return got_error(GOT_ERR_PRIVSEP_LEN);
475 	memcpy(&ihave, imsg->data, sizeof(ihave));
476 
477 	memset(&id, 0, sizeof(id));
478 	memcpy(id.sha1, ihave.object_id, SHA1_DIGEST_LENGTH);
479 
480 	if (log_getverbose() > 0 &&
481 	    got_sha1_digest_to_str(id.sha1, hex, sizeof(hex)))
482 		log_debug("client has %s", hex);
483 
484 	imsg_init(&ibuf, client->fd);
485 
486 	err = got_object_get_type(&obj_type, repo_read.repo, &id);
487 	if (err) {
488 		if (err->code == GOT_ERR_NO_OBJ) {
489 			gotd_imsg_send_nak(&id, &ibuf,
490 			    PROC_REPO_READ, repo_read.pid);
491 			err = NULL;
492 		}
493 		goto done;
494 	}
495 
496 	if (obj_type != GOT_OBJ_TYPE_COMMIT &&
497 	    obj_type != GOT_OBJ_TYPE_TAG) {
498 		gotd_imsg_send_nak(&id, &ibuf, PROC_REPO_READ, repo_read.pid);
499 		err = got_error(GOT_ERR_OBJ_TYPE);
500 		goto done;
501 	}
502 
503 	err = record_object_id(&client->have_ids, &id);
504 	if (err)
505 		return err;
506 
507 	gotd_imsg_send_ack(&id, &ibuf, PROC_REPO_READ, repo_read.pid);
508 done:
509 	imsg_clear(&ibuf);
510 	return err;
511 }
512 
513 struct repo_read_pack_progress_arg {
514 	int report_progress;
515 	struct imsgbuf *ibuf;
516 	int sent_ready;
517 };
518 
519 static const struct got_error *
520 pack_progress(void *arg, int ncolored, int nfound, int ntrees,
521     off_t packfile_size, int ncommits, int nobj_total, int nobj_deltify,
522     int nobj_written)
523 {
524 	struct repo_read_pack_progress_arg *a = arg;
525 	struct gotd_imsg_packfile_progress iprog;
526 	int ret;
527 
528 	if (!a->report_progress)
529 		return NULL;
530 	if (packfile_size > 0 && a->sent_ready)
531 		return NULL;
532 
533 	memset(&iprog, 0, sizeof(iprog));
534 	iprog.ncolored = ncolored;
535 	iprog.nfound = nfound;
536 	iprog.ntrees = ntrees;
537 	iprog.packfile_size = packfile_size;
538 	iprog.ncommits = ncommits;
539 	iprog.nobj_total = nobj_total;
540 	iprog.nobj_deltify = nobj_deltify;
541 	iprog.nobj_written = nobj_written;
542 
543 	/* Using synchronous writes since we are blocking the event loop. */
544 	if (packfile_size == 0) {
545 		ret = imsg_compose(a->ibuf, GOTD_IMSG_PACKFILE_PROGRESS,
546 		    PROC_REPO_READ, repo_read.pid, -1, &iprog, sizeof(iprog));
547 		if (ret == -1) {
548 			return got_error_from_errno("imsg compose "
549 			    "PACKFILE_PROGRESS");
550 		}
551 	} else {
552 		a->sent_ready = 1;
553 		ret = imsg_compose(a->ibuf, GOTD_IMSG_PACKFILE_READY,
554 		    PROC_REPO_READ, repo_read.pid, -1, &iprog, sizeof(iprog));
555 		if (ret == -1) {
556 			return got_error_from_errno("imsg compose "
557 			    "PACKFILE_READY");
558 		}
559 	}
560 
561 	return gotd_imsg_flush(a->ibuf);
562 }
563 
564 static const struct got_error *
565 receive_delta_cache_fd(struct imsg *imsg,
566     struct gotd_imsgev *iev)
567 {
568 	struct repo_read_client *client = &repo_read_client;
569 	struct gotd_imsg_send_packfile ireq;
570 	size_t datalen;
571 
572 	log_debug("receving delta cache file");
573 
574 	if (imsg->fd == -1)
575 		return got_error(GOT_ERR_PRIVSEP_NO_FD);
576 
577 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
578 	if (datalen != sizeof(ireq))
579 		return got_error(GOT_ERR_PRIVSEP_LEN);
580 	memcpy(&ireq, imsg->data, sizeof(ireq));
581 
582 	if (client->delta_cache_fd != -1)
583 		return got_error(GOT_ERR_PRIVSEP_MSG);
584 
585 	client->delta_cache_fd = imsg->fd;
586 	client->report_progress = ireq.report_progress;
587 	return NULL;
588 }
589 
590 static const struct got_error *
591 receive_pack_pipe(struct imsg *imsg, struct gotd_imsgev *iev)
592 {
593 	struct repo_read_client *client = &repo_read_client;
594 	struct gotd_imsg_packfile_pipe ireq;
595 	size_t datalen;
596 
597 	log_debug("receving pack pipe descriptor");
598 
599 	if (imsg->fd == -1)
600 		return got_error(GOT_ERR_PRIVSEP_NO_FD);
601 
602 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
603 	if (datalen != sizeof(ireq))
604 		return got_error(GOT_ERR_PRIVSEP_LEN);
605 	memcpy(&ireq, imsg->data, sizeof(ireq));
606 
607 	if (client->pack_pipe != -1)
608 		return got_error(GOT_ERR_PRIVSEP_MSG);
609 
610 	client->pack_pipe = imsg->fd;
611 	return NULL;
612 }
613 
614 static const struct got_error *
615 send_packfile(struct imsg *imsg, struct gotd_imsgev *iev)
616 {
617 	const struct got_error *err = NULL;
618 	struct repo_read_client *client = &repo_read_client;
619 	struct gotd_imsg_packfile_done idone;
620 	uint8_t packsha1[SHA1_DIGEST_LENGTH];
621 	char hex[SHA1_DIGEST_STRING_LENGTH];
622 	FILE *delta_cache = NULL;
623 	struct imsgbuf ibuf;
624 	struct repo_read_pack_progress_arg pa;
625 	struct got_ratelimit rl;
626 
627 	log_debug("packfile request received");
628 
629 	got_ratelimit_init(&rl, 2, 0);
630 
631 	if (client->delta_cache_fd == -1 || client->pack_pipe == -1)
632 		return got_error(GOT_ERR_PRIVSEP_NO_FD);
633 
634 	imsg_init(&ibuf, client->fd);
635 
636 	delta_cache = fdopen(client->delta_cache_fd, "w+");
637 	if (delta_cache == NULL) {
638 		err = got_error_from_errno("fdopen");
639 		goto done;
640 	}
641 	client->delta_cache_fd = -1;
642 
643 	memset(&pa, 0, sizeof(pa));
644 	pa.ibuf = &ibuf;
645 	pa.report_progress = client->report_progress;
646 
647 	err = got_pack_create(packsha1, client->pack_pipe, delta_cache,
648 	    client->have_ids.ids, client->have_ids.nids,
649 	    client->want_ids.ids, client->want_ids.nids,
650 	    repo_read.repo, 0, 1, 0, pack_progress, &pa, &rl,
651 	    check_cancelled, NULL);
652 	if (err)
653 		goto done;
654 
655 	if (log_getverbose() > 0 &&
656 	    got_sha1_digest_to_str(packsha1, hex, sizeof(hex)))
657 		log_debug("sent pack-%s.pack", hex);
658 
659 	memset(&idone, 0, sizeof(idone));
660 	idone.client_id = client->id;
661 	if (gotd_imsg_compose_event(iev, GOTD_IMSG_PACKFILE_DONE,
662 	    PROC_REPO_READ, -1, &idone, sizeof(idone)) == -1)
663 		err = got_error_from_errno("imsg compose PACKFILE_DONE");
664 done:
665 	if (delta_cache != NULL && fclose(delta_cache) == EOF && err == NULL)
666 		err = got_error_from_errno("fclose");
667 	imsg_clear(&ibuf);
668 	return err;
669 }
670 
671 static void
672 repo_read_dispatch_session(int fd, short event, void *arg)
673 {
674 	const struct got_error *err = NULL;
675 	struct gotd_imsgev *iev = arg;
676 	struct imsgbuf *ibuf = &iev->ibuf;
677 	struct imsg imsg;
678 	ssize_t n;
679 	int shut = 0;
680 	struct repo_read_client *client = &repo_read_client;
681 
682 	if (event & EV_READ) {
683 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
684 			fatal("imsg_read error");
685 		if (n == 0)	/* Connection closed. */
686 			shut = 1;
687 	}
688 
689 	if (event & EV_WRITE) {
690 		n = msgbuf_write(&ibuf->w);
691 		if (n == -1 && errno != EAGAIN)
692 			fatal("msgbuf_write");
693 		if (n == 0)	/* Connection closed. */
694 			shut = 1;
695 	}
696 
697 	while (err == NULL && check_cancelled(NULL) == NULL) {
698 		if ((n = imsg_get(ibuf, &imsg)) == -1)
699 			fatal("%s: imsg_get", __func__);
700 		if (n == 0)	/* No more messages. */
701 			break;
702 
703 		if (imsg.hdr.type != GOTD_IMSG_LIST_REFS_INTERNAL &&
704 		    client->id == 0) {
705 			err = got_error(GOT_ERR_PRIVSEP_MSG);
706 			break;
707 		}
708 
709 		switch (imsg.hdr.type) {
710 		case GOTD_IMSG_LIST_REFS_INTERNAL:
711 			err = list_refs(&imsg);
712 			if (err)
713 				log_warnx("%s: ls-refs: %s", repo_read.title,
714 				    err->msg);
715 			break;
716 		case GOTD_IMSG_WANT:
717 			err = recv_want(&imsg);
718 			if (err)
719 				log_warnx("%s: want-line: %s", repo_read.title,
720 				    err->msg);
721 			break;
722 		case GOTD_IMSG_HAVE:
723 			err = recv_have(&imsg);
724 			if (err)
725 				log_warnx("%s: have-line: %s", repo_read.title,
726 				    err->msg);
727 			break;
728 		case GOTD_IMSG_SEND_PACKFILE:
729 			err = receive_delta_cache_fd(&imsg, iev);
730 			if (err)
731 				log_warnx("%s: receiving delta cache: %s",
732 				    repo_read.title, err->msg);
733 			break;
734 		case GOTD_IMSG_PACKFILE_PIPE:
735 			err = receive_pack_pipe(&imsg, iev);
736 			if (err) {
737 				log_warnx("%s: receiving pack pipe: %s",
738 				    repo_read.title, err->msg);
739 				break;
740 			}
741 			err = send_packfile(&imsg, iev);
742 			if (err)
743 				log_warnx("%s: sending packfile: %s",
744 				    repo_read.title, err->msg);
745 			break;
746 		default:
747 			log_debug("%s: unexpected imsg %d", repo_read.title,
748 			    imsg.hdr.type);
749 			break;
750 		}
751 
752 		imsg_free(&imsg);
753 	}
754 
755 	if (!shut && check_cancelled(NULL) == NULL) {
756 		if (err &&
757 		    gotd_imsg_send_error_event(iev, PROC_REPO_READ,
758 		        client->id, err) == -1) {
759 			log_warnx("could not send error to parent: %s",
760 			    err->msg);
761 		}
762 		gotd_imsg_event_add(iev);
763 	} else {
764 		/* This pipe is dead. Remove its event handler */
765 		event_del(&iev->ev);
766 		event_loopexit(NULL);
767 	}
768 }
769 
770 static const struct got_error *
771 recv_connect(struct imsg *imsg)
772 {
773 	struct gotd_imsgev *iev = &repo_read.session_iev;
774 	size_t datalen;
775 
776 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
777 	if (datalen != 0)
778 		return got_error(GOT_ERR_PRIVSEP_LEN);
779 	if (imsg->fd == -1)
780 		return got_error(GOT_ERR_PRIVSEP_NO_FD);
781 
782 	if (repo_read.session_fd != -1)
783 		return got_error(GOT_ERR_PRIVSEP_MSG);
784 
785 	repo_read.session_fd = imsg->fd;
786 
787 	imsg_init(&iev->ibuf, repo_read.session_fd);
788 	iev->handler = repo_read_dispatch_session;
789 	iev->events = EV_READ;
790 	iev->handler_arg = NULL;
791 	event_set(&iev->ev, iev->ibuf.fd, EV_READ,
792 	    repo_read_dispatch_session, iev);
793 	gotd_imsg_event_add(iev);
794 
795 	return NULL;
796 }
797 
798 static void
799 repo_read_dispatch(int fd, short event, void *arg)
800 {
801 	const struct got_error *err = NULL;
802 	struct gotd_imsgev *iev = arg;
803 	struct imsgbuf *ibuf = &iev->ibuf;
804 	struct imsg imsg;
805 	ssize_t n;
806 	int shut = 0;
807 	struct repo_read_client *client = &repo_read_client;
808 
809 	if (event & EV_READ) {
810 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
811 			fatal("imsg_read error");
812 		if (n == 0)	/* Connection closed. */
813 			shut = 1;
814 	}
815 
816 	if (event & EV_WRITE) {
817 		n = msgbuf_write(&ibuf->w);
818 		if (n == -1 && errno != EAGAIN)
819 			fatal("msgbuf_write");
820 		if (n == 0)	/* Connection closed. */
821 			shut = 1;
822 	}
823 
824 	while (err == NULL && check_cancelled(NULL) == NULL) {
825 		if ((n = imsg_get(ibuf, &imsg)) == -1)
826 			fatal("%s: imsg_get", __func__);
827 		if (n == 0)	/* No more messages. */
828 			break;
829 
830 		switch (imsg.hdr.type) {
831 		case GOTD_IMSG_CONNECT_REPO_CHILD:
832 			err = recv_connect(&imsg);
833 			break;
834 		default:
835 			log_debug("%s: unexpected imsg %d", repo_read.title,
836 			    imsg.hdr.type);
837 			break;
838 		}
839 
840 		imsg_free(&imsg);
841 	}
842 
843 	if (!shut && check_cancelled(NULL) == NULL) {
844 		if (err &&
845 		    gotd_imsg_send_error_event(iev, PROC_REPO_READ,
846 		        client->id, err) == -1) {
847 			log_warnx("could not send error to parent: %s",
848 			    err->msg);
849 		}
850 		gotd_imsg_event_add(iev);
851 	} else {
852 		/* This pipe is dead. Remove its event handler */
853 		event_del(&iev->ev);
854 		event_loopexit(NULL);
855 	}
856 }
857 
858 void
859 repo_read_main(const char *title, const char *repo_path,
860     int *pack_fds, int *temp_fds)
861 {
862 	const struct got_error *err = NULL;
863 	struct repo_read_client *client = &repo_read_client;
864 	struct gotd_imsgev iev;
865 
866 	client->fd = -1;
867 	client->delta_cache_fd = -1;
868 	client->pack_pipe = -1;
869 
870 	repo_read.title = title;
871 	repo_read.pid = getpid();
872 	repo_read.pack_fds = pack_fds;
873 	repo_read.temp_fds = temp_fds;
874 	repo_read.session_fd = -1;
875 	repo_read.session_iev.ibuf.fd = -1;
876 
877 	err = got_repo_open(&repo_read.repo, repo_path, NULL, pack_fds);
878 	if (err)
879 		goto done;
880 	if (!got_repo_is_bare(repo_read.repo)) {
881 		err = got_error_msg(GOT_ERR_NOT_GIT_REPO,
882 		    "bare git repository required");
883 		goto done;
884 	}
885 
886 	got_repo_temp_fds_set(repo_read.repo, temp_fds);
887 
888 	signal(SIGINT, catch_sigint);
889 	signal(SIGTERM, catch_sigterm);
890 	signal(SIGPIPE, SIG_IGN);
891 	signal(SIGHUP, SIG_IGN);
892 
893 	imsg_init(&iev.ibuf, GOTD_FILENO_MSG_PIPE);
894 	iev.handler = repo_read_dispatch;
895 	iev.events = EV_READ;
896 	iev.handler_arg = NULL;
897 	event_set(&iev.ev, iev.ibuf.fd, EV_READ, repo_read_dispatch, &iev);
898 
899 	if (gotd_imsg_compose_event(&iev, GOTD_IMSG_REPO_CHILD_READY,
900 	    PROC_REPO_READ, -1, NULL, 0) == -1) {
901 		err = got_error_from_errno("imsg compose REPO_CHILD_READY");
902 		goto done;
903 	}
904 
905 	event_dispatch();
906 done:
907 	if (err)
908 		log_warnx("%s: %s", title, err->msg);
909 	repo_read_shutdown();
910 }
911 
912 void
913 repo_read_shutdown(void)
914 {
915 	struct repo_read_client *client = &repo_read_client;
916 
917 	log_debug("%s: shutting down", repo_read.title);
918 
919 	free_object_ids(&client->have_ids);
920 	free_object_ids(&client->want_ids);
921 	if (client->fd != -1)
922 		close(client->fd);
923 	if (client->delta_cache_fd != -1)
924 		close(client->delta_cache_fd);
925 	if (client->pack_pipe != -1)
926 		close(client->pack_pipe);
927 
928 	if (repo_read.repo)
929 		got_repo_close(repo_read.repo);
930 	got_repo_pack_fds_close(repo_read.pack_fds);
931 	got_repo_temp_fds_close(repo_read.temp_fds);
932 	if (repo_read.session_fd != -1)
933 		close(repo_read.session_fd);
934 	exit(0);
935 }