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Date:: Fri Dec 30 16:19:01 2022 UTC
Message:: convert gotd repo_read.c and repo_write.c to single-client Because these processes are now started on demand per client connection there is no need to keep track of multiple clients anymore. Also, these processes can now exit when a disconnect event is received. ok op, jamsek
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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 } repo_read;
64 
65 static struct repo_read_client {
66 	uint32_t			 id;
67 	int				 fd;
68 	int				 delta_cache_fd;
69 	int				 report_progress;
70 	int				 pack_pipe;
71 	struct gotd_object_id_array	 want_ids;
72 	struct gotd_object_id_array	 have_ids;
73 } repo_read_client;
74 
75 static volatile sig_atomic_t sigint_received;
76 static volatile sig_atomic_t sigterm_received;
77 
78 static void
79 catch_sigint(int signo)
80 {
81 	sigint_received = 1;
82 }
83 
84 static void
85 catch_sigterm(int signo)
86 {
87 	sigterm_received = 1;
88 }
89 
90 static const struct got_error *
91 check_cancelled(void *arg)
92 {
93 	if (sigint_received || sigterm_received)
94 		return got_error(GOT_ERR_CANCELLED);
95 
96 	return NULL;
97 }
98 
99 static const struct got_error *
100 send_symref(struct got_reference *symref, struct got_object_id *target_id,
101     struct imsgbuf *ibuf)
102 {
103 	const struct got_error *err = NULL;
104 	struct gotd_imsg_symref isymref;
105 	const char *refname = got_ref_get_name(symref);
106 	const char *target = got_ref_get_symref_target(symref);
107 	size_t len;
108 	struct ibuf *wbuf;
109 
110 	memset(&isymref, 0, sizeof(isymref));
111 	isymref.name_len = strlen(refname);
112 	isymref.target_len = strlen(target);
113 	memcpy(isymref.target_id, target_id->sha1, sizeof(isymref.target_id));
114 
115 	len = sizeof(isymref) + isymref.name_len + isymref.target_len;
116 	if (len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
117 		err = got_error(GOT_ERR_NO_SPACE);
118 		goto done;
119 	}
120 
121 	wbuf = imsg_create(ibuf, GOTD_IMSG_SYMREF, 0, 0, len);
122 	if (wbuf == NULL) {
123 		err = got_error_from_errno("imsg_create SYMREF");
124 		goto done;
125 	}
126 
127 	if (imsg_add(wbuf, &isymref, sizeof(isymref)) == -1) {
128 		err = got_error_from_errno("imsg_add SYMREF");
129 		goto done;
130 	}
131 	if (imsg_add(wbuf, refname, isymref.name_len) == -1) {
132 		err = got_error_from_errno("imsg_add SYMREF");
133 		goto done;
134 	}
135 	if (imsg_add(wbuf, target, isymref.target_len) == -1) {
136 		err = got_error_from_errno("imsg_add SYMREF");
137 		goto done;
138 	}
139 
140 	wbuf->fd = -1;
141 	imsg_close(ibuf, wbuf);
142 done:
143 	free(target_id);
144 	return err;
145 }
146 
147 static const struct got_error *
148 send_peeled_tag_ref(struct got_reference *ref, struct got_object *obj,
149     struct imsgbuf *ibuf)
150 {
151 	const struct got_error *err = NULL;
152 	struct got_tag_object *tag;
153 	size_t namelen, len;
154 	char *peeled_refname = NULL;
155 	struct got_object_id *id;
156 	struct ibuf *wbuf;
157 
158 	err = got_object_tag_open(&tag, repo_read.repo, obj);
159 	if (err)
160 		return err;
161 
162 	if (asprintf(&peeled_refname, "%s^{}", got_ref_get_name(ref)) == -1) {
163 		err = got_error_from_errno("asprintf");
164 		goto done;
165 	}
166 
167 	id = got_object_tag_get_object_id(tag);
168 	namelen = strlen(peeled_refname);
169 
170 	len = sizeof(struct gotd_imsg_ref) + namelen;
171 	if (len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
172 		err = got_error(GOT_ERR_NO_SPACE);
173 		goto done;
174 	}
175 
176 	wbuf = imsg_create(ibuf, GOTD_IMSG_REF, PROC_REPO_READ,
177 	    repo_read.pid, len);
178 	if (wbuf == NULL) {
179 		err = got_error_from_errno("imsg_create MREF");
180 		goto done;
181 	}
182 
183 	/* Keep in sync with struct gotd_imsg_ref definition. */
184 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
185 		err = got_error_from_errno("imsg_add REF");
186 		goto done;
187 	}
188 	if (imsg_add(wbuf, &namelen, sizeof(namelen)) == -1) {
189 		err = got_error_from_errno("imsg_add REF");
190 		goto done;
191 	}
192 	if (imsg_add(wbuf, peeled_refname, namelen) == -1) {
193 		err = got_error_from_errno("imsg_add REF");
194 		goto done;
195 	}
196 
197 	wbuf->fd = -1;
198 	imsg_close(ibuf, wbuf);
199 done:
200 	got_object_tag_close(tag);
201 	return err;
202 }
203 
204 static const struct got_error *
205 send_ref(struct got_reference *ref, struct imsgbuf *ibuf)
206 {
207 	const struct got_error *err;
208 	const char *refname = got_ref_get_name(ref);
209 	size_t namelen;
210 	struct got_object_id *id = NULL;
211 	struct got_object *obj = NULL;
212 	size_t len;
213 	struct ibuf *wbuf;
214 
215 	namelen = strlen(refname);
216 
217 	len = sizeof(struct gotd_imsg_ref) + namelen;
218 	if (len > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
219 		return got_error(GOT_ERR_NO_SPACE);
220 
221 	err = got_ref_resolve(&id, repo_read.repo, ref);
222 	if (err)
223 		return err;
224 
225 	wbuf = imsg_create(ibuf, GOTD_IMSG_REF, PROC_REPO_READ,
226 	    repo_read.pid, len);
227 	if (wbuf == NULL) {
228 		err = got_error_from_errno("imsg_create REF");
229 		goto done;
230 	}
231 
232 	/* Keep in sync with struct gotd_imsg_ref definition. */
233 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
234 		return got_error_from_errno("imsg_add REF");
235 	if (imsg_add(wbuf, &namelen, sizeof(namelen)) == -1)
236 		return got_error_from_errno("imsg_add REF");
237 	if (imsg_add(wbuf, refname, namelen) == -1)
238 		return got_error_from_errno("imsg_add REF");
239 
240 	wbuf->fd = -1;
241 	imsg_close(ibuf, wbuf);
242 
243 	err = got_object_open(&obj, repo_read.repo, id);
244 	if (err)
245 		goto done;
246 	if (obj->type == GOT_OBJ_TYPE_TAG)
247 		err = send_peeled_tag_ref(ref, obj, ibuf);
248 done:
249 	if (obj)
250 		got_object_close(obj);
251 	free(id);
252 	return err;
253 }
254 
255 static const struct got_error *
256 list_refs(struct imsg *imsg)
257 {
258 	const struct got_error *err;
259 	struct repo_read_client *client = &repo_read_client;
260 	struct got_reflist_head refs;
261 	struct got_reflist_entry *re;
262 	struct gotd_imsg_list_refs_internal ireq;
263 	size_t datalen;
264 	struct gotd_imsg_reflist irefs;
265 	struct imsgbuf ibuf;
266 	int client_fd = imsg->fd;
267 	struct got_object_id *head_target_id = NULL;
268 
269 	TAILQ_INIT(&refs);
270 
271 	if (client_fd == -1)
272 		return got_error(GOT_ERR_PRIVSEP_NO_FD);
273 
274 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
275 	if (datalen != sizeof(ireq))
276 		return got_error(GOT_ERR_PRIVSEP_LEN);
277 	memcpy(&ireq, imsg->data, sizeof(ireq));
278 
279 	if (ireq.client_id == 0)
280 		return got_error(GOT_ERR_CLIENT_ID);
281 	if (client->id != 0) {
282 		return got_error_msg(GOT_ERR_CLIENT_ID,
283 		    "duplicate list-refs request");
284 	}
285 	client->id = ireq.client_id;
286 	client->fd = client_fd;
287 	client->delta_cache_fd = -1;
288 	client->pack_pipe = -1;
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, 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 const struct got_error *
672 recv_disconnect(struct imsg *imsg)
673 {
674 	const struct got_error *err = NULL;
675 	struct gotd_imsg_disconnect idisconnect;
676 	size_t datalen;
677 	int delta_cache_fd, pack_pipe;
678 	struct repo_read_client *client = &repo_read_client;
679 
680 	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
681 	if (datalen != sizeof(idisconnect))
682 		return got_error(GOT_ERR_PRIVSEP_LEN);
683 	memcpy(&idisconnect, imsg->data, sizeof(idisconnect));
684 
685 	log_debug("client disconnecting");
686 
687 	free_object_ids(&client->have_ids);
688 	free_object_ids(&client->want_ids);
689 	if (close(client->fd) == -1)
690 		err = got_error_from_errno("close");
691 	delta_cache_fd = client->delta_cache_fd;
692 	if (delta_cache_fd != -1 && close(delta_cache_fd) == -1 && err == NULL)
693 		return got_error_from_errno("close");
694 	pack_pipe = client->pack_pipe;
695 	if (pack_pipe != -1 && close(pack_pipe) == -1 && err == NULL)
696 		return got_error_from_errno("close");
697 	return err;
698 }
699 
700 static void
701 repo_read_dispatch(int fd, short event, void *arg)
702 {
703 	const struct got_error *err = NULL;
704 	struct gotd_imsgev *iev = arg;
705 	struct imsgbuf *ibuf = &iev->ibuf;
706 	struct imsg imsg;
707 	ssize_t n;
708 	int shut = 0;
709 	struct repo_read_client *client = &repo_read_client;
710 
711 	if (event & EV_READ) {
712 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
713 			fatal("imsg_read error");
714 		if (n == 0)	/* Connection closed. */
715 			shut = 1;
716 	}
717 
718 	if (event & EV_WRITE) {
719 		n = msgbuf_write(&ibuf->w);
720 		if (n == -1 && errno != EAGAIN)
721 			fatal("msgbuf_write");
722 		if (n == 0)	/* Connection closed. */
723 			shut = 1;
724 	}
725 
726 	while (err == NULL && check_cancelled(NULL) == NULL) {
727 		if ((n = imsg_get(ibuf, &imsg)) == -1)
728 			fatal("%s: imsg_get", __func__);
729 		if (n == 0)	/* No more messages. */
730 			break;
731 
732 		if (imsg.hdr.type != GOTD_IMSG_LIST_REFS_INTERNAL &&
733 		    client->id == 0) {
734 			err = got_error(GOT_ERR_PRIVSEP_MSG);
735 			break;
736 		}
737 
738 		switch (imsg.hdr.type) {
739 		case GOTD_IMSG_LIST_REFS_INTERNAL:
740 			err = list_refs(&imsg);
741 			if (err)
742 				log_warnx("%s: ls-refs: %s", repo_read.title,
743 				    err->msg);
744 			break;
745 		case GOTD_IMSG_WANT:
746 			err = recv_want(&imsg);
747 			if (err)
748 				log_warnx("%s: want-line: %s", repo_read.title,
749 				    err->msg);
750 			break;
751 		case GOTD_IMSG_HAVE:
752 			err = recv_have(&imsg);
753 			if (err)
754 				log_warnx("%s: have-line: %s", repo_read.title,
755 				    err->msg);
756 			break;
757 		case GOTD_IMSG_SEND_PACKFILE:
758 			err = receive_delta_cache_fd(&imsg, iev);
759 			if (err)
760 				log_warnx("%s: receiving delta cache: %s",
761 				    repo_read.title, err->msg);
762 			break;
763 		case GOTD_IMSG_PACKFILE_PIPE:
764 			err = receive_pack_pipe(&imsg, iev);
765 			if (err) {
766 				log_warnx("%s: receiving pack pipe: %s",
767 				    repo_read.title, err->msg);
768 				break;
769 			}
770 			err = send_packfile(&imsg, iev);
771 			if (err)
772 				log_warnx("%s: sending packfile: %s",
773 				    repo_read.title, err->msg);
774 			break;
775 		case GOTD_IMSG_DISCONNECT:
776 			err = recv_disconnect(&imsg);
777 			if (err)
778 				log_warnx("%s: disconnect: %s",
779 				    repo_read.title, err->msg);
780 			shut = 1;
781 			break;
782 		default:
783 			log_debug("%s: unexpected imsg %d", repo_read.title,
784 			    imsg.hdr.type);
785 			break;
786 		}
787 
788 		imsg_free(&imsg);
789 	}
790 
791 	if (!shut && check_cancelled(NULL) == NULL) {
792 		if (err &&
793 		    gotd_imsg_send_error_event(iev, PROC_REPO_READ,
794 		        client->id, err) == -1) {
795 			log_warnx("could not send error to parent: %s",
796 			    err->msg);
797 		}
798 		gotd_imsg_event_add(iev);
799 	} else {
800 		/* This pipe is dead. Remove its event handler */
801 		event_del(&iev->ev);
802 		event_loopexit(NULL);
803 	}
804 }
805 
806 void
807 repo_read_main(const char *title, const char *repo_path,
808     int *pack_fds, int *temp_fds)
809 {
810 	const struct got_error *err = NULL;
811 	struct gotd_imsgev iev;
812 
813 	repo_read.title = title;
814 	repo_read.pid = getpid();
815 	repo_read.pack_fds = pack_fds;
816 	repo_read.temp_fds = temp_fds;
817 
818 	err = got_repo_open(&repo_read.repo, repo_path, NULL, pack_fds);
819 	if (err)
820 		goto done;
821 	if (!got_repo_is_bare(repo_read.repo)) {
822 		err = got_error_msg(GOT_ERR_NOT_GIT_REPO,
823 		    "bare git repository required");
824 		goto done;
825 	}
826 
827 	got_repo_temp_fds_set(repo_read.repo, temp_fds);
828 
829 	signal(SIGINT, catch_sigint);
830 	signal(SIGTERM, catch_sigterm);
831 	signal(SIGPIPE, SIG_IGN);
832 	signal(SIGHUP, SIG_IGN);
833 
834 	imsg_init(&iev.ibuf, GOTD_FILENO_MSG_PIPE);
835 	iev.handler = repo_read_dispatch;
836 	iev.events = EV_READ;
837 	iev.handler_arg = NULL;
838 	event_set(&iev.ev, iev.ibuf.fd, EV_READ, repo_read_dispatch, &iev);
839 
840 	if (gotd_imsg_compose_event(&iev, GOTD_IMSG_REPO_CHILD_READY,
841 	    PROC_REPO_READ, -1, NULL, 0) == -1) {
842 		err = got_error_from_errno("imsg compose REPO_CHILD_READY");
843 		goto done;
844 	}
845 
846 	event_dispatch();
847 done:
848 	if (err)
849 		log_warnx("%s: %s", title, err->msg);
850 	repo_read_shutdown();
851 }
852 
853 void
854 repo_read_shutdown(void)
855 {
856 	log_debug("%s: shutting down", repo_read.title);
857 	if (repo_read.repo)
858 		got_repo_close(repo_read.repo);
859 	got_repo_pack_fds_close(repo_read.pack_fds);
860 	got_repo_temp_fds_close(repo_read.temp_fds);
861 	exit(0);
862 }