1 /*
2  * Copyright (c) 2020 Ori Bernstein
3  * Copyright (c) 2021 Stefan Sperling <stsp@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/uio.h>
20 #include <sys/stat.h>
21 #include <sys/time.h>
22 #include <sys/mman.h>
23 
24 #include <errno.h>
25 #include <stdint.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <time.h>
30 #include <unistd.h>
31 #include <limits.h>
32 #include <zlib.h>
33 
34 #if defined(__FreeBSD__)
35 #include <unistd.h>
36 #endif
37 
38 #include "got_error.h"
39 #include "got_cancel.h"
40 #include "got_object.h"
41 #include "got_path.h"
42 #include "got_reference.h"
43 #include "got_repository_admin.h"
44 #include "got_opentemp.h"
45 
46 #include "got_lib_deltify.h"
47 #include "got_lib_delta.h"
48 #include "got_lib_object.h"
49 #include "got_lib_object_idset.h"
50 #include "got_lib_object_cache.h"
51 #include "got_lib_deflate.h"
52 #include "got_lib_pack.h"
53 #include "got_lib_pack_create.h"
54 #include "got_lib_privsep.h"
55 #include "got_lib_repository.h"
56 #include "got_lib_ratelimit.h"
57 #include "got_lib_inflate.h"
58 
59 #include "murmurhash2.h"
60 
61 #ifndef MIN
62 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
63 #endif
64 
65 #ifndef MAX
66 #define	MAX(_a,_b) ((_a) > (_b) ? (_a) : (_b))
67 #endif
68 
69 #ifndef nitems
70 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
71 #endif
72 
73 struct got_pack_meta {
74 	struct got_object_id id;
75 	uint32_t path_hash;
76 	int	obj_type;
77 	off_t	size;
78 	time_t	mtime;
79 
80 	/* The best delta we picked */
81 	struct got_pack_meta *head;
82 	struct got_pack_meta *prev;
83 	unsigned char *delta_buf; /* if encoded in memory (compressed) */
84 	off_t	delta_offset;	/* offset in delta cache file (compressed) */
85 	off_t	delta_len;	/* encoded delta length */
86 	off_t	delta_compressed_len; /* encoded+compressed delta length */
87 	int	nchain;
88 
89 	off_t   reused_delta_offset; /* offset of delta in reused pack file */
90 	struct got_object_id *base_obj_id;
91 
92 	/* Only used for delta window */
93 	struct got_delta_table *dtab;
94 
95 	/* Only used for writing offset deltas */
96 	off_t	off;
97 };
98 
99 struct got_pack_metavec {
100 	struct got_pack_meta **meta;
101 	int nmeta;
102 	int metasz;
103 };
104 
105 static const struct got_error *
106 alloc_meta(struct got_pack_meta **new, struct got_object_id *id,
107     const char *path, int obj_type, time_t mtime, uint32_t seed)
108 {
109 	struct got_pack_meta *m;
110 
111 	*new = NULL;
112 
113 	m = calloc(1, sizeof(*m));
114 	if (m == NULL)
115 		return got_error_from_errno("calloc");
116 
117 	memcpy(&m->id, id, sizeof(m->id));
118 
119 	m->path_hash = murmurhash2(path, strlen(path), seed);
120 	m->obj_type = obj_type;
121 	m->mtime = mtime;
122 	*new = m;
123 	return NULL;
124 }
125 
126 static void
127 clear_meta(struct got_pack_meta *meta)
128 {
129 	if (meta == NULL)
130 		return;
131 	meta->path_hash = 0;
132 	free(meta->delta_buf);
133 	meta->delta_buf = NULL;
134 	free(meta->base_obj_id);
135 	meta->base_obj_id = NULL;
136 	meta->reused_delta_offset = 0;
137 }
138 
139 static void
140 free_nmeta(struct got_pack_meta **meta, int nmeta)
141 {
142 	int i;
143 
144 	for (i = 0; i < nmeta; i++)
145 		clear_meta(meta[i]);
146 	free(meta);
147 }
148 
149 static int
150 delta_order_cmp(const void *pa, const void *pb)
151 {
152 	struct got_pack_meta *a, *b;
153 
154 	a = *(struct got_pack_meta **)pa;
155 	b = *(struct got_pack_meta **)pb;
156 
157 	if (a->obj_type != b->obj_type)
158 		return a->obj_type - b->obj_type;
159 	if (a->path_hash < b->path_hash)
160 		return -1;
161 	if (a->path_hash > b->path_hash)
162 		return 1;
163 	if (a->mtime < b->mtime)
164 		return -1;
165 	if (a->mtime > b->mtime)
166 		return 1;
167 	return got_object_id_cmp(&a->id, &b->id);
168 }
169 
170 static off_t
171 delta_size(struct got_delta_instruction *deltas, int ndeltas)
172 {
173 	int i;
174 	off_t size = 32;
175 	for (i = 0; i < ndeltas; i++) {
176 		if (deltas[i].copy)
177 			size += GOT_DELTA_SIZE_SHIFT;
178 		else
179 			size += deltas[i].len + 1;
180 	}
181 	return size;
182 }
183 
184 static const struct got_error *
185 append(unsigned char **p, size_t *len, off_t *sz, void *seg, int nseg)
186 {
187 	char *n;
188 
189 	if (*len + nseg >= *sz) {
190 		while (*len + nseg >= *sz)
191 			*sz += *sz / 2;
192 		n = realloc(*p, *sz);
193 		if (n == NULL)
194 			return got_error_from_errno("realloc");
195 		*p = n;
196 	}
197 	memcpy(*p + *len, seg, nseg);
198 	*len += nseg;
199 	return NULL;
200 }
201 
202 static const struct got_error *
203 encode_delta_in_mem(struct got_pack_meta *m, struct got_raw_object *o,
204     struct got_delta_instruction *deltas, int ndeltas,
205     off_t delta_size, off_t base_size)
206 {
207 	const struct got_error *err;
208 	unsigned char buf[16], *bp;
209 	int i, j;
210 	size_t len = 0, compressed_len;
211 	off_t bufsize = delta_size;
212 	off_t n;
213 	struct got_delta_instruction *d;
214 	uint8_t *delta_buf;
215 
216 	delta_buf = malloc(bufsize);
217 	if (delta_buf == NULL)
218 		return got_error_from_errno("malloc");
219 
220 	/* base object size */
221 	buf[0] = base_size & GOT_DELTA_SIZE_VAL_MASK;
222 	n = base_size >> GOT_DELTA_SIZE_SHIFT;
223 	for (i = 1; n > 0; i++) {
224 		buf[i - 1] |= GOT_DELTA_SIZE_MORE;
225 		buf[i] = n & GOT_DELTA_SIZE_VAL_MASK;
226 		n >>= GOT_DELTA_SIZE_SHIFT;
227 	}
228 	err = append(&delta_buf, &len, &bufsize, buf, i);
229 	if (err)
230 		goto done;
231 
232 	/* target object size */
233 	buf[0] = o->size & GOT_DELTA_SIZE_VAL_MASK;
234 	n = o->size >> GOT_DELTA_SIZE_SHIFT;
235 	for (i = 1; n > 0; i++) {
236 		buf[i - 1] |= GOT_DELTA_SIZE_MORE;
237 		buf[i] = n & GOT_DELTA_SIZE_VAL_MASK;
238 		n >>= GOT_DELTA_SIZE_SHIFT;
239 	}
240 	err = append(&delta_buf, &len, &bufsize, buf, i);
241 	if (err)
242 		goto done;
243 
244 	for (j = 0; j < ndeltas; j++) {
245 		d = &deltas[j];
246 		if (d->copy) {
247 			n = d->offset;
248 			bp = &buf[1];
249 			buf[0] = GOT_DELTA_BASE_COPY;
250 			for (i = 0; i < 4; i++) {
251 				/* DELTA_COPY_OFF1 ... DELTA_COPY_OFF4 */
252 				buf[0] |= 1 << i;
253 				*bp++ = n & 0xff;
254 				n >>= 8;
255 				if (n == 0)
256 					break;
257 			}
258 
259 			n = d->len;
260 			if (n != GOT_DELTA_COPY_DEFAULT_LEN) {
261 				/* DELTA_COPY_LEN1 ... DELTA_COPY_LEN3 */
262 				for (i = 0; i < 3 && n > 0; i++) {
263 					buf[0] |= 1 << (i + 4);
264 					*bp++ = n & 0xff;
265 					n >>= 8;
266 				}
267 			}
268 			err = append(&delta_buf, &len, &bufsize,
269 			    buf, bp - buf);
270 			if (err)
271 				goto done;
272 		} else if (o->f == NULL) {
273 			n = 0;
274 			while (n != d->len) {
275 				buf[0] = (d->len - n < 127) ? d->len - n : 127;
276 				err = append(&delta_buf, &len, &bufsize,
277 				    buf, 1);
278 				if (err)
279 					goto done;
280 				err = append(&delta_buf, &len, &bufsize,
281 				    o->data + o->hdrlen + d->offset + n,
282 				    buf[0]);
283 				if (err)
284 					goto done;
285 				n += buf[0];
286 			}
287 		} else {
288 			char content[128];
289 			size_t r;
290 			if (fseeko(o->f, o->hdrlen + d->offset, SEEK_SET) == -1) {
291 				err = got_error_from_errno("fseeko");
292 				goto done;
293 			}
294 			n = 0;
295 			while (n != d->len) {
296 				buf[0] = (d->len - n < 127) ? d->len - n : 127;
297 				err = append(&delta_buf, &len, &bufsize,
298 				    buf, 1);
299 				if (err)
300 					goto done;
301 				r = fread(content, 1, buf[0], o->f);
302 				if (r != buf[0]) {
303 					err = got_ferror(o->f, GOT_ERR_IO);
304 					goto done;
305 				}
306 				err = append(&delta_buf, &len, &bufsize,
307 				    content, buf[0]);
308 				if (err)
309 					goto done;
310 				n += buf[0];
311 			}
312 		}
313 	}
314 
315 	err = got_deflate_to_mem_mmap(&m->delta_buf, &compressed_len,
316 	    NULL, NULL, delta_buf, 0, len);
317 	if (err)
318 		goto done;
319 
320 	m->delta_len = len;
321 	m->delta_compressed_len = compressed_len;
322 done:
323 	free(delta_buf);
324 	return err;
325 }
326 
327 static const struct got_error *
328 encode_delta(struct got_pack_meta *m, struct got_raw_object *o,
329     struct got_delta_instruction *deltas, int ndeltas,
330     off_t base_size, FILE *f)
331 {
332 	const struct got_error *err;
333 	unsigned char buf[16], *bp;
334 	int i, j;
335 	off_t n;
336 	struct got_deflate_buf zb;
337 	struct got_delta_instruction *d;
338 	off_t delta_len = 0, compressed_len = 0;
339 
340 	err = got_deflate_init(&zb, NULL, GOT_DEFLATE_BUFSIZE);
341 	if (err)
342 		return err;
343 
344 	/* base object size */
345 	buf[0] = base_size & GOT_DELTA_SIZE_VAL_MASK;
346 	n = base_size >> GOT_DELTA_SIZE_SHIFT;
347 	for (i = 1; n > 0; i++) {
348 		buf[i - 1] |= GOT_DELTA_SIZE_MORE;
349 		buf[i] = n & GOT_DELTA_SIZE_VAL_MASK;
350 		n >>= GOT_DELTA_SIZE_SHIFT;
351 	}
352 
353 	err = got_deflate_append_to_file_mmap(&zb, &compressed_len,
354 	    buf, 0, i, f, NULL);
355 	if (err)
356 		goto done;
357 	delta_len += i;
358 
359 	/* target object size */
360 	buf[0] = o->size & GOT_DELTA_SIZE_VAL_MASK;
361 	n = o->size >> GOT_DELTA_SIZE_SHIFT;
362 	for (i = 1; n > 0; i++) {
363 		buf[i - 1] |= GOT_DELTA_SIZE_MORE;
364 		buf[i] = n & GOT_DELTA_SIZE_VAL_MASK;
365 		n >>= GOT_DELTA_SIZE_SHIFT;
366 	}
367 
368 	err = got_deflate_append_to_file_mmap(&zb, &compressed_len,
369 	    buf, 0, i, f, NULL);
370 	if (err)
371 		goto done;
372 	delta_len += i;
373 
374 	for (j = 0; j < ndeltas; j++) {
375 		d = &deltas[j];
376 		if (d->copy) {
377 			n = d->offset;
378 			bp = &buf[1];
379 			buf[0] = GOT_DELTA_BASE_COPY;
380 			for (i = 0; i < 4; i++) {
381 				/* DELTA_COPY_OFF1 ... DELTA_COPY_OFF4 */
382 				buf[0] |= 1 << i;
383 				*bp++ = n & 0xff;
384 				n >>= 8;
385 				if (n == 0)
386 					break;
387 			}
388 			n = d->len;
389 			if (n != GOT_DELTA_COPY_DEFAULT_LEN) {
390 				/* DELTA_COPY_LEN1 ... DELTA_COPY_LEN3 */
391 				for (i = 0; i < 3 && n > 0; i++) {
392 					buf[0] |= 1 << (i + 4);
393 					*bp++ = n & 0xff;
394 					n >>= 8;
395 				}
396 			}
397 			err = got_deflate_append_to_file_mmap(&zb,
398 			    &compressed_len, buf, 0, bp - buf, f, NULL);
399 			if (err)
400 				goto done;
401 			delta_len += (bp - buf);
402 		} else if (o->f == NULL) {
403 			n = 0;
404 			while (n != d->len) {
405 				buf[0] = (d->len - n < 127) ? d->len - n : 127;
406 				err = got_deflate_append_to_file_mmap(&zb,
407 				    &compressed_len, buf, 0, 1, f, NULL);
408 				if (err)
409 					goto done;
410 				delta_len++;
411 				err = got_deflate_append_to_file_mmap(&zb,
412 				    &compressed_len,
413 				    o->data + o->hdrlen + d->offset + n, 0,
414 				    buf[0], f, NULL);
415 				if (err)
416 					goto done;
417 				delta_len += buf[0];
418 				n += buf[0];
419 			}
420 		} else {
421 			char content[128];
422 			size_t r;
423 			if (fseeko(o->f, o->hdrlen + d->offset, SEEK_SET) == -1) {
424 				err = got_error_from_errno("fseeko");
425 				goto done;
426 			}
427 			n = 0;
428 			while (n != d->len) {
429 				buf[0] = (d->len - n < 127) ? d->len - n : 127;
430 				err = got_deflate_append_to_file_mmap(&zb,
431 				    &compressed_len, buf, 0, 1, f, NULL);
432 				if (err)
433 					goto done;
434 				delta_len++;
435 				r = fread(content, 1, buf[0], o->f);
436 				if (r != buf[0]) {
437 					err = got_ferror(o->f, GOT_ERR_IO);
438 					goto done;
439 				}
440 				err = got_deflate_append_to_file_mmap(&zb,
441 				    &compressed_len, content, 0, buf[0], f,
442 				    NULL);
443 				if (err)
444 					goto done;
445 				delta_len += buf[0];
446 				n += buf[0];
447 			}
448 		}
449 	}
450 
451 	err = got_deflate_flush(&zb, f, NULL, &compressed_len);
452 	if (err)
453 		goto done;
454 
455 	/* sanity check */
456 	if (compressed_len != ftello(f) - m->delta_offset) {
457 		err = got_error(GOT_ERR_COMPRESSION);
458 		goto done;
459 	}
460 
461 	m->delta_len = delta_len;
462 	m->delta_compressed_len = compressed_len;
463 done:
464 	got_deflate_end(&zb);
465 	return err;
466 }
467 
468 static const struct got_error *
469 report_progress(got_pack_progress_cb progress_cb, void *progress_arg,
470     struct got_ratelimit *rl, int ncolored, int nfound, int ntrees,
471     off_t packfile_size, int ncommits, int nobj_total, int obj_deltify,
472     int nobj_written)
473 {
474 	const struct got_error *err;
475 	int elapsed;
476 
477 	if (progress_cb == NULL)
478 		return NULL;
479 
480 	err = got_ratelimit_check(&elapsed, rl);
481 	if (err || !elapsed)
482 		return err;
483 
484 	return progress_cb(progress_arg, ncolored, nfound, ntrees,
485 	    packfile_size, ncommits, nobj_total, obj_deltify, nobj_written);
486 }
487 
488 static const struct got_error *
489 add_meta(struct got_pack_meta *m, struct got_pack_metavec *v)
490 {
491 	if (v->nmeta == v->metasz){
492 		size_t newsize = 2 * v->metasz;
493 		struct got_pack_meta **new;
494 		new = reallocarray(v->meta, newsize, sizeof(*new));
495 		if (new == NULL)
496 			return got_error_from_errno("reallocarray");
497 		v->meta = new;
498 		v->metasz = newsize; 
499 	}
500 
501 	v->meta[v->nmeta++] = m;
502 	return NULL;
503 }
504 
505 static const struct got_error *
506 find_pack_for_reuse(struct got_packidx **best_packidx,
507     struct got_repository *repo)
508 {
509 	const struct got_error *err = NULL;
510 	struct got_pathlist_entry *pe;
511 	const char *best_packidx_path = NULL;
512 	int nobj_max = 0;
513 
514 	*best_packidx = NULL;
515 
516 	TAILQ_FOREACH(pe, &repo->packidx_paths, entry) {
517 		const char *path_packidx = pe->path;
518 		struct got_packidx *packidx;
519 		int nobj;
520 
521 		err = got_repo_get_packidx(&packidx, path_packidx, repo);
522 		if (err)
523 			break;
524 
525 		nobj = be32toh(packidx->hdr.fanout_table[0xff]);
526 		if (nobj > nobj_max) {
527 			best_packidx_path = path_packidx;
528 			nobj_max = nobj;
529 		}
530 	}
531 
532 	if (best_packidx_path) {
533 		err = got_repo_get_packidx(best_packidx, best_packidx_path,
534 		    repo);
535 	}
536 
537 	return err;
538 }
539 
540 struct send_id_arg {
541 	struct imsgbuf *ibuf;
542 	struct got_object_id *ids[GOT_IMSG_OBJ_ID_LIST_MAX_NIDS];
543 	size_t nids;
544 };
545 
546 static const struct got_error *
547 send_id(struct got_object_id *id, void *data, void *arg)
548 {
549 	const struct got_error *err = NULL;
550 	struct send_id_arg *a = arg;
551 
552 	a->ids[a->nids++] = id;
553 
554 	if (a->nids >= GOT_IMSG_OBJ_ID_LIST_MAX_NIDS) {
555 		err = got_privsep_send_object_idlist(a->ibuf, a->ids, a->nids);
556 		if (err)
557 			return err;
558 		a->nids = 0;
559 	}
560 
561 	return NULL;
562 }
563 
564 static const struct got_error *
565 recv_reused_delta(struct got_imsg_reused_delta *delta,
566     struct got_object_idset *idset, struct got_pack_metavec *v)
567 {
568 	struct got_pack_meta *m, *base;
569 
570 	if (delta->delta_offset + delta->delta_size < delta->delta_offset ||
571 	    delta->delta_offset +
572 	    delta->delta_compressed_size < delta->delta_offset)
573 		return got_error(GOT_ERR_BAD_PACKFILE);
574 
575 	m = got_object_idset_get(idset, &delta->id);
576 	if (m == NULL)
577 		return got_error(GOT_ERR_NO_OBJ);
578 
579 	base = got_object_idset_get(idset, &delta->base_id);
580 	if (base == NULL)
581 		return got_error(GOT_ERR_NO_OBJ);
582 
583 	m->delta_len = delta->delta_size;
584 	m->delta_compressed_len = delta->delta_compressed_size;
585 	m->delta_offset = delta->delta_out_offset;
586 	m->prev = base;
587 	m->size = delta->result_size;
588 	m->reused_delta_offset = delta->delta_offset;
589 	m->base_obj_id = got_object_id_dup(&delta->base_id);
590 	if (m->base_obj_id == NULL)
591 		return got_error_from_errno("got_object_id_dup");
592 
593 	return add_meta(m, v);
594 }
595 
596 static const struct got_error *
597 search_deltas(struct got_pack_metavec *v, struct got_object_idset *idset,
598     int delta_cache_fd, int ncolored, int nfound, int ntrees, int ncommits,
599     struct got_repository *repo,
600     got_pack_progress_cb progress_cb, void *progress_arg,
601     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
602 {
603 	const struct got_error *err = NULL;
604 	struct got_packidx *packidx;
605 	struct got_pack *pack;
606 	struct send_id_arg sia;
607 	struct got_imsg_reused_delta deltas[GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS];
608 	size_t ndeltas, i;
609 
610 	err = find_pack_for_reuse(&packidx, repo);
611 	if (err)
612 		return err;
613 
614 	if (packidx == NULL)
615 		return NULL;
616 
617 	err = got_object_prepare_delta_reuse(&pack, packidx,
618 	    delta_cache_fd, repo);
619 	if (err)
620 		return err;
621 
622 	memset(&sia, 0, sizeof(sia));
623 	sia.ibuf = pack->privsep_child->ibuf;
624 	err = got_object_idset_for_each(idset, send_id, &sia);
625 	if (err)
626 		return err;
627 	if (sia.nids > 0) {
628 		err = got_privsep_send_object_idlist(pack->privsep_child->ibuf,
629 		    sia.ids, sia.nids);
630 		if (err)
631 			return err;
632 	}
633 	err = got_privsep_send_object_idlist_done(pack->privsep_child->ibuf);
634 	if (err)
635 		return err;
636 
637 	for (;;) {
638 		int done = 0;
639 
640 		if (cancel_cb) {
641 			err = (*cancel_cb)(cancel_arg);
642 			if (err)
643 				break;
644 		}
645 
646 		err = got_privsep_recv_reused_deltas(&done, deltas, &ndeltas,
647 		    pack->privsep_child->ibuf);
648 		if (err || done)
649 			break;
650 
651 		for (i = 0; i < ndeltas; i++) {
652 			struct got_imsg_reused_delta *delta = &deltas[i];
653 			err = recv_reused_delta(delta, idset, v);
654 			if (err)
655 				goto done;
656 		}
657 
658 		err = report_progress(progress_cb, progress_arg, rl,
659 		    ncolored, nfound, ntrees, 0L, ncommits,
660 		    got_object_idset_num_elements(idset), v->nmeta, 0);
661 		if (err)
662 			break;
663 	}
664 done:
665 	return err;
666 }
667 
668 static const struct got_error *
669 pick_deltas(struct got_pack_meta **meta, int nmeta, int ncolored,
670     int nfound, int ntrees, int ncommits, int nreused, FILE *delta_cache,
671     struct got_repository *repo,
672     got_pack_progress_cb progress_cb, void *progress_arg,
673     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
674 {
675 	const struct got_error *err = NULL;
676 	struct got_pack_meta *m = NULL, *base = NULL;
677 	struct got_raw_object *raw = NULL, *base_raw = NULL;
678 	struct got_delta_instruction *deltas = NULL, *best_deltas = NULL;
679 	int i, j, ndeltas, best_ndeltas;
680 	off_t size, best_size;
681 	const int max_base_candidates = 3;
682 	size_t delta_memsize = 0;
683 	const size_t max_delta_memsize = 4 * GOT_DELTA_RESULT_SIZE_CACHED_MAX;
684 	int outfd = -1;
685 	uint32_t delta_seed;
686 
687 	delta_seed = arc4random();
688 
689 	qsort(meta, nmeta, sizeof(struct got_pack_meta *), delta_order_cmp);
690 	for (i = 0; i < nmeta; i++) {
691 		if (cancel_cb) {
692 			err = (*cancel_cb)(cancel_arg);
693 			if (err)
694 				break;
695 		}
696 		err = report_progress(progress_cb, progress_arg, rl,
697 		    ncolored, nfound, ntrees, 0L, ncommits, nreused + nmeta,
698 		    nreused + i, 0);
699 		if (err)
700 			goto done;
701 		m = meta[i];
702 
703 		if (m->obj_type == GOT_OBJ_TYPE_COMMIT ||
704 		    m->obj_type == GOT_OBJ_TYPE_TAG)
705 			continue;
706 
707 		err = got_object_raw_open(&raw, &outfd, repo, &m->id);
708 		if (err)
709 			goto done;
710 		m->size = raw->size;
711 
712 		if (raw->f == NULL) {
713 			err = got_deltify_init_mem(&m->dtab, raw->data,
714 			    raw->hdrlen, raw->size + raw->hdrlen, delta_seed);
715 		} else {
716 			err = got_deltify_init(&m->dtab, raw->f, raw->hdrlen,
717 			    raw->size + raw->hdrlen, delta_seed);
718 		}
719 		if (err)
720 			goto done;
721 
722 		if (i > max_base_candidates) {
723 			struct got_pack_meta *n = NULL;
724 			n = meta[i - (max_base_candidates + 1)];
725 			got_deltify_free(n->dtab);
726 			n->dtab = NULL;
727 		}
728 
729 		best_size = raw->size;
730 		best_ndeltas = 0;
731 		for (j = MAX(0, i - max_base_candidates); j < i; j++) {
732 			if (cancel_cb) {
733 				err = (*cancel_cb)(cancel_arg);
734 				if (err)
735 					goto done;
736 			}
737 			base = meta[j];
738 			/* long chains make unpacking slow, avoid such bases */
739 			if (base->nchain >= 128 ||
740 			    base->obj_type != m->obj_type)
741 				continue;
742 
743 			err = got_object_raw_open(&base_raw, &outfd, repo,
744 			    &base->id);
745 			if (err)
746 				goto done;
747 
748 			if (raw->f == NULL && base_raw->f == NULL) {
749 				err = got_deltify_mem_mem(&deltas, &ndeltas,
750 				    raw->data, raw->hdrlen,
751 				    raw->size + raw->hdrlen, delta_seed,
752 				    base->dtab, base_raw->data,
753 				    base_raw->hdrlen,
754 				    base_raw->size + base_raw->hdrlen);
755 			} else if (raw->f == NULL) {
756 				err = got_deltify_mem_file(&deltas, &ndeltas,
757 				    raw->data, raw->hdrlen,
758 				    raw->size + raw->hdrlen, delta_seed,
759 				    base->dtab, base_raw->f,
760 				    base_raw->hdrlen,
761 				    base_raw->size + base_raw->hdrlen);
762 			} else if (base_raw->f == NULL) {
763 				err = got_deltify_file_mem(&deltas, &ndeltas,
764 				    raw->f, raw->hdrlen,
765 				    raw->size + raw->hdrlen, delta_seed,
766 				    base->dtab, base_raw->data,
767 				    base_raw->hdrlen,
768 				    base_raw->size + base_raw->hdrlen);
769 			} else {
770 				err = got_deltify(&deltas, &ndeltas,
771 				    raw->f, raw->hdrlen,
772 				    raw->size + raw->hdrlen, delta_seed,
773 				    base->dtab, base_raw->f, base_raw->hdrlen,
774 				    base_raw->size + base_raw->hdrlen);
775 			}
776 			got_object_raw_close(base_raw);
777 			base_raw = NULL;
778 			if (err)
779 				goto done;
780 
781 			size = delta_size(deltas, ndeltas);
782 			if (size + 32 < best_size){
783 				/*
784 				 * if we already picked a best delta,
785 				 * replace it.
786 				 */
787 				best_size = size;
788 				free(best_deltas);
789 				best_deltas = deltas;
790 				best_ndeltas = ndeltas;
791 				deltas = NULL;
792 				m->nchain = base->nchain + 1;
793 				m->prev = base;
794 				m->head = base->head;
795 				if (m->head == NULL)
796 					m->head = base;
797 			} else {
798 				free(deltas);
799 				deltas = NULL;
800 				ndeltas = 0;
801 			}
802 		}
803 
804 		if (best_ndeltas > 0) {
805 			if (best_size <= GOT_DELTA_RESULT_SIZE_CACHED_MAX &&
806 			    delta_memsize + best_size <= max_delta_memsize) {
807 				delta_memsize += best_size;
808 				err = encode_delta_in_mem(m, raw, best_deltas,
809 				    best_ndeltas, best_size, m->prev->size);
810 			} else {
811 				m->delta_offset = ftello(delta_cache);
812 				err = encode_delta(m, raw, best_deltas,
813 				    best_ndeltas, m->prev->size, delta_cache);
814 			}
815 			free(best_deltas);
816 			best_deltas = NULL;
817 			best_ndeltas = 0;
818 			if (err)
819 				goto done;
820 		}
821 
822 		got_object_raw_close(raw);
823 		raw = NULL;
824 	}
825 done:
826 	for (i = MAX(0, nmeta - max_base_candidates); i < nmeta; i++) {
827 		got_deltify_free(meta[i]->dtab);
828 		meta[i]->dtab = NULL;
829 	}
830 	if (raw)
831 		got_object_raw_close(raw);
832 	if (base_raw)
833 		got_object_raw_close(base_raw);
834 	if (outfd != -1 && close(outfd) == -1 && err == NULL)
835 		err = got_error_from_errno("close");
836 	free(deltas);
837 	free(best_deltas);
838 	return err;
839 }
840 
841 static const struct got_error *
842 search_packidx(int *found, struct got_object_id *id,
843     struct got_repository *repo)
844 {
845 	const struct got_error *err = NULL;
846 	struct got_packidx *packidx = NULL;
847 	int idx;
848 
849 	*found = 0;
850 
851 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
852 	if (err == NULL)
853 		*found = 1; /* object is already packed */
854 	else if (err->code == GOT_ERR_NO_OBJ)
855 		err = NULL;
856 	return err;
857 }
858 
859 static const struct got_error *
860 add_object(int want_meta, struct got_object_idset *idset,
861     struct got_object_id *id, const char *path, int obj_type,
862     time_t mtime, uint32_t seed, int loose_obj_only,
863     struct got_repository *repo, int *ncolored, int *nfound, int *ntrees,
864     got_pack_progress_cb progress_cb, void *progress_arg,
865     struct got_ratelimit *rl)
866 {
867 	const struct got_error *err;
868 	struct got_pack_meta *m = NULL;
869 
870 	if (loose_obj_only) {
871 		int is_packed;
872 		err = search_packidx(&is_packed, id, repo);
873 		if (err)
874 			return err;
875 		if (is_packed && want_meta)
876 			return NULL;
877 	}
878 
879 	if (want_meta) {
880 		err = alloc_meta(&m, id, path, obj_type, mtime, seed);
881 		if (err)
882 			return err;
883 
884 		(*nfound)++;
885 		err = report_progress(progress_cb, progress_arg, rl,
886 		    *ncolored, *nfound, *ntrees, 0L, 0, 0, 0, 0);
887 		if (err) {
888 			clear_meta(m);
889 			free(m);
890 			return err;
891 		}
892 	}
893 
894 	err = got_object_idset_add(idset, id, m);
895 	if (err) {
896 		clear_meta(m);
897 		free(m);
898 	}
899 	return err;
900 }
901 
902 static const struct got_error *
903 load_tree_entries(struct got_object_id_queue *ids, int want_meta,
904     struct got_object_idset *idset, struct got_object_idset *idset_exclude,
905     struct got_object_id *tree_id,
906     const char *dpath, time_t mtime, uint32_t seed, struct got_repository *repo,
907     int loose_obj_only, int *ncolored, int *nfound, int *ntrees,
908     got_pack_progress_cb progress_cb, void *progress_arg,
909     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
910 {
911 	const struct got_error *err;
912 	struct got_tree_object *tree;
913 	char *p = NULL;
914 	int i;
915 
916 	err = got_object_open_as_tree(&tree, repo, tree_id);
917 	if (err)
918 		return err;
919 
920 	(*ntrees)++;
921 	err = report_progress(progress_cb, progress_arg, rl,
922 	    *ncolored, *nfound, *ntrees, 0L, 0, 0, 0, 0);
923 	if (err)
924 		return err;
925 
926 	for (i = 0; i < got_object_tree_get_nentries(tree); i++) {
927 		struct got_tree_entry *e = got_object_tree_get_entry(tree, i);
928 		struct got_object_id *id = got_tree_entry_get_id(e);
929 		mode_t mode = got_tree_entry_get_mode(e);
930 
931 		if (cancel_cb) {
932 			err = (*cancel_cb)(cancel_arg);
933 			if (err)
934 				break;
935 		}
936 
937 		if (got_object_tree_entry_is_submodule(e) ||
938 		    got_object_idset_contains(idset, id) ||
939 		    got_object_idset_contains(idset_exclude, id))
940 			continue;
941 		
942 		if (asprintf(&p, "%s%s%s", dpath, dpath[0] != '\0' ? "/" : "",
943 		    got_tree_entry_get_name(e)) == -1) {
944 			err = got_error_from_errno("asprintf");
945 			break;
946 		}
947 
948 		if (S_ISDIR(mode)) {
949 			struct got_object_qid *qid;
950 			err = got_object_qid_alloc(&qid, id);
951 			if (err)
952 				break;
953 			qid->data = p;
954 			p = NULL;
955 			STAILQ_INSERT_TAIL(ids, qid, entry);
956 		} else if (S_ISREG(mode) || S_ISLNK(mode)) {
957 			err = add_object(want_meta,
958 			    want_meta ? idset : idset_exclude, id, p,
959 			    GOT_OBJ_TYPE_BLOB, mtime, seed, loose_obj_only,
960 			    repo, ncolored, nfound, ntrees,
961 			    progress_cb, progress_arg, rl);
962 			if (err)
963 				break;
964 			free(p);
965 			p = NULL;
966 		} else {
967 			free(p);
968 			p = NULL;
969 		}
970 	}
971 
972 	got_object_tree_close(tree);
973 	free(p);
974 	return err;
975 }
976 
977 static const struct got_error *
978 load_tree(int want_meta, struct got_object_idset *idset,
979     struct got_object_idset *idset_exclude,
980     struct got_object_id *tree_id, const char *dpath, time_t mtime,
981     uint32_t seed, struct got_repository *repo, int loose_obj_only,
982     int *ncolored, int *nfound, int *ntrees,
983     got_pack_progress_cb progress_cb, void *progress_arg,
984     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
985 {
986 	const struct got_error *err = NULL;
987 	struct got_object_id_queue tree_ids;
988 	struct got_object_qid *qid;
989 
990 	if (got_object_idset_contains(idset, tree_id) ||
991 	    got_object_idset_contains(idset_exclude, tree_id))
992 		return NULL;
993 
994 	err = got_object_qid_alloc(&qid, tree_id);
995 	if (err)
996 		return err;
997 	qid->data = strdup(dpath);
998 	if (qid->data == NULL) {
999 		err = got_error_from_errno("strdup");
1000 		got_object_qid_free(qid);
1001 		return err;
1002 	}
1003 
1004 	STAILQ_INIT(&tree_ids);
1005 	STAILQ_INSERT_TAIL(&tree_ids, qid, entry);
1006 
1007 	while (!STAILQ_EMPTY(&tree_ids)) {
1008 		const char *path;
1009 		if (cancel_cb) {
1010 			err = (*cancel_cb)(cancel_arg);
1011 			if (err)
1012 				break;
1013 		}
1014 
1015 		qid = STAILQ_FIRST(&tree_ids);
1016 		STAILQ_REMOVE_HEAD(&tree_ids, entry);
1017 		path = qid->data;
1018 
1019 		if (got_object_idset_contains(idset, &qid->id) ||
1020 		    got_object_idset_contains(idset_exclude, &qid->id)) {
1021 			free(qid->data);
1022 			got_object_qid_free(qid);
1023 			continue;
1024 		}
1025 
1026 		err = add_object(want_meta, want_meta ? idset : idset_exclude,
1027 		    &qid->id, path, GOT_OBJ_TYPE_TREE,
1028 		    mtime, seed, loose_obj_only, repo,
1029 		    ncolored, nfound, ntrees, progress_cb, progress_arg, rl);
1030 		if (err) {
1031 			free(qid->data);
1032 			got_object_qid_free(qid);
1033 			break;
1034 		}
1035 
1036 		err = load_tree_entries(&tree_ids, want_meta, idset,
1037 		    idset_exclude, &qid->id,
1038 		    path, mtime, seed, repo, loose_obj_only, ncolored, nfound,
1039 		    ntrees, progress_cb, progress_arg, rl,
1040 		    cancel_cb, cancel_arg);
1041 		free(qid->data);
1042 		got_object_qid_free(qid);
1043 		if (err)
1044 			break;
1045 	}
1046 
1047 	STAILQ_FOREACH(qid, &tree_ids, entry)
1048 		free(qid->data);
1049 	got_object_id_queue_free(&tree_ids);
1050 	return err;
1051 }
1052 
1053 static const struct got_error *
1054 load_commit(int want_meta, struct got_object_idset *idset,
1055     struct got_object_idset *idset_exclude,
1056     struct got_object_id *id, struct got_repository *repo, uint32_t seed,
1057     int loose_obj_only, int *ncolored, int *nfound, int *ntrees,
1058     got_pack_progress_cb progress_cb, void *progress_arg,
1059     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
1060 {
1061 	const struct got_error *err;
1062 	struct got_commit_object *commit;
1063 
1064 	if (got_object_idset_contains(idset, id) ||
1065 	    got_object_idset_contains(idset_exclude, id))
1066 		return NULL;
1067 
1068 	if (loose_obj_only) {
1069 		int is_packed;
1070 		err = search_packidx(&is_packed, id, repo);
1071 		if (err)
1072 			return err;
1073 		if (is_packed && want_meta)
1074 			return NULL;
1075 	}
1076 
1077 	err = got_object_open_as_commit(&commit, repo, id);
1078 	if (err)
1079 		return err;
1080 
1081 	err = add_object(want_meta, want_meta ? idset : idset_exclude,
1082 	    id, "", GOT_OBJ_TYPE_COMMIT,
1083 	    got_object_commit_get_committer_time(commit), seed,
1084 	    loose_obj_only, repo,
1085 	    ncolored, nfound, ntrees, progress_cb, progress_arg, rl);
1086 	if (err)
1087 		goto done;
1088 
1089 	err = load_tree(want_meta, idset, idset_exclude,
1090 	    got_object_commit_get_tree_id(commit),
1091 	    "", got_object_commit_get_committer_time(commit), seed,
1092 	    repo, loose_obj_only, ncolored, nfound, ntrees,
1093 	    progress_cb, progress_arg, rl, cancel_cb, cancel_arg);
1094 done:
1095 	got_object_commit_close(commit);
1096 	return err;
1097 }
1098 
1099 static const struct got_error *
1100 load_tag(int want_meta, struct got_object_idset *idset,
1101     struct got_object_idset *idset_exclude,
1102     struct got_object_id *id, struct got_repository *repo, uint32_t seed,
1103     int loose_obj_only, int *ncolored, int *nfound, int *ntrees,
1104     got_pack_progress_cb progress_cb, void *progress_arg,
1105     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
1106 {
1107 	const struct got_error *err;
1108 	struct got_tag_object *tag = NULL;
1109 
1110 	if (got_object_idset_contains(idset, id) ||
1111 	    got_object_idset_contains(idset_exclude, id))
1112 		return NULL;
1113 
1114 	if (loose_obj_only) {
1115 		int is_packed;
1116 		err = search_packidx(&is_packed, id, repo);
1117 		if (err)
1118 			return err;
1119 		if (is_packed && want_meta)
1120 			return NULL;
1121 	}
1122 
1123 	err = got_object_open_as_tag(&tag, repo, id);
1124 	if (err)
1125 		return err;
1126 
1127 	err = add_object(want_meta, want_meta ? idset : idset_exclude,
1128 	    id, "", GOT_OBJ_TYPE_TAG,
1129 	    got_object_tag_get_tagger_time(tag), seed, loose_obj_only, repo,
1130 	    ncolored, nfound, ntrees, progress_cb, progress_arg, rl);
1131 	if (err)
1132 		goto done;
1133 
1134 	switch (got_object_tag_get_object_type(tag)) {
1135 	case GOT_OBJ_TYPE_COMMIT:
1136 		err = load_commit(want_meta, idset, idset_exclude,
1137 		    got_object_tag_get_object_id(tag), repo, seed,
1138 		    loose_obj_only, ncolored, nfound, ntrees,
1139 		    progress_cb, progress_arg, rl, cancel_cb, cancel_arg);
1140 		break;
1141 	case GOT_OBJ_TYPE_TREE:
1142 		err = load_tree(want_meta, idset, idset_exclude,
1143 		    got_object_tag_get_object_id(tag), "",
1144 		    got_object_tag_get_tagger_time(tag), seed, repo,
1145 		    loose_obj_only, ncolored, nfound, ntrees,
1146 		    progress_cb, progress_arg, rl, cancel_cb, cancel_arg);
1147 		break;
1148 	default:
1149 		break;
1150 	}
1151 
1152 done:
1153 	got_object_tag_close(tag);
1154 	return err;
1155 }
1156 
1157 enum findtwixt_color {
1158 	COLOR_KEEP = 0,
1159 	COLOR_DROP,
1160 	COLOR_BLANK,
1161 	COLOR_SKIP,
1162 };
1163 
1164 static const int findtwixt_colors[] = {
1165 	COLOR_KEEP,
1166 	COLOR_DROP,
1167 	COLOR_BLANK,
1168 	COLOR_SKIP,
1169 };
1170 
1171 static const struct got_error *
1172 paint_commit(struct got_object_qid *qid, int color)
1173 {
1174 	if (color < 0 || color >= nitems(findtwixt_colors))
1175 		return got_error(GOT_ERR_RANGE);
1176 
1177 	qid->data = (void *)&findtwixt_colors[color];
1178 	return NULL;
1179 }
1180 
1181 static const struct got_error *
1182 queue_commit_id(struct got_object_id_queue *ids, struct got_object_id *id,
1183     int color, struct got_repository *repo)
1184 {
1185 	const struct got_error *err;
1186 	struct got_object_qid *qid;
1187 
1188 	err = got_object_qid_alloc(&qid, id);
1189 	if (err)
1190 		return err;
1191 
1192 	STAILQ_INSERT_TAIL(ids, qid, entry);
1193 	return paint_commit(qid, color);
1194 }
1195 
1196 struct append_id_arg {
1197 	struct got_object_id **array;
1198 	int idx;
1199 	struct got_object_idset *drop;
1200 	struct got_object_idset *skip;
1201 };
1202 
1203 static const struct got_error *
1204 append_id(struct got_object_id *id, void *data, void *arg)
1205 {
1206 	struct append_id_arg *a = arg;
1207 
1208 	if (got_object_idset_contains(a->skip, id) ||
1209 	    got_object_idset_contains(a->drop, id))
1210 		return NULL;
1211 
1212 	a->array[++a->idx] = got_object_id_dup(id);
1213 	if (a->array[a->idx] == NULL)
1214 		return got_error_from_errno("got_object_id_dup");
1215 
1216 	return NULL;
1217 }
1218 
1219 static const struct got_error *
1220 queue_commit_or_tag_id(struct got_object_id *id, int color,
1221     struct got_object_id_queue *ids, struct got_repository *repo)
1222 {
1223 	const struct got_error *err;
1224 	struct got_tag_object *tag = NULL;
1225 	int obj_type;
1226 
1227 	err = got_object_get_type(&obj_type, repo, id);
1228 	if (err)
1229 		return err;
1230 
1231 	if (obj_type == GOT_OBJ_TYPE_TAG) {
1232 		err = got_object_open_as_tag(&tag, repo, id);
1233 		if (err)
1234 			return err;
1235 		obj_type = got_object_tag_get_object_type(tag);
1236 		id = got_object_tag_get_object_id(tag);
1237 	}
1238 
1239 	if (obj_type == GOT_OBJ_TYPE_COMMIT) {
1240 		err = queue_commit_id(ids, id, color, repo);
1241 		if (err)
1242 			goto done;
1243 	}
1244 done:
1245 	if (tag)
1246 		got_object_tag_close(tag);
1247 	return err;
1248 }
1249 
1250 static const struct got_error *
1251 paint_commits(int *ncolored, struct got_object_id_queue *ids, int nids,
1252     struct got_object_idset *keep, struct got_object_idset *drop,
1253     struct got_object_idset *skip, struct got_repository *repo,
1254     got_pack_progress_cb progress_cb, void *progress_arg,
1255     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
1256 {
1257 	const struct got_error *err = NULL;
1258 	struct got_commit_object *commit = NULL;
1259 	const struct got_object_id_queue *parents;
1260 	struct got_object_qid *qid;
1261 	int nqueued = nids, nskip = 0;
1262 
1263 	while (!STAILQ_EMPTY(ids) && nskip != nqueued) {
1264 		int color;
1265 
1266 		if (cancel_cb) {
1267 			err = cancel_cb(cancel_arg);
1268 			if (err)
1269 				break;
1270 		}
1271 
1272 		qid = STAILQ_FIRST(ids);
1273 		STAILQ_REMOVE_HEAD(ids, entry);
1274 		nqueued--;
1275 		color = *((int *)qid->data);
1276 		if (color == COLOR_SKIP)
1277 			nskip--;
1278 
1279 		if (got_object_idset_contains(skip, &qid->id)) {
1280 			got_object_qid_free(qid);
1281 			continue;
1282 		}
1283 
1284 		switch (color) {
1285 		case COLOR_KEEP:
1286 			if (got_object_idset_contains(keep, &qid->id)) {
1287 				got_object_qid_free(qid);
1288 				continue;
1289 			}
1290 			if (got_object_idset_contains(drop, &qid->id)) {
1291 				err = paint_commit(qid, COLOR_SKIP);
1292 				if (err)
1293 					goto done;
1294 			} else
1295 				(*ncolored)++;
1296 			err = got_object_idset_add(keep, &qid->id, NULL);
1297 			if (err)
1298 				goto done;
1299 			break;
1300 		case COLOR_DROP:
1301 			if (got_object_idset_contains(drop, &qid->id)) {
1302 				got_object_qid_free(qid);
1303 				continue;
1304 			}
1305 			if (got_object_idset_contains(keep, &qid->id)) {
1306 				err = paint_commit(qid, COLOR_SKIP);
1307 				if (err)
1308 					goto done;
1309 			} else
1310 				(*ncolored)++;
1311 			err = got_object_idset_add(drop, &qid->id, NULL);
1312 			if (err)
1313 				goto done;
1314 			break;
1315 		case COLOR_SKIP:
1316 			if (!got_object_idset_contains(skip, &qid->id)) {
1317 				err = got_object_idset_add(skip, &qid->id,
1318 				    NULL);
1319 				if (err)
1320 					goto done;
1321 			}
1322 			break;
1323 		default:
1324 			/* should not happen */
1325 			err = got_error_fmt(GOT_ERR_NOT_IMPL,
1326 			    "%s invalid commit color %d", __func__, color);
1327 			goto done;
1328 		}
1329 
1330 		err = report_progress(progress_cb, progress_arg, rl,
1331 		    *ncolored, 0, 0, 0L, 0, 0, 0, 0);
1332 		if (err)
1333 			break;
1334 
1335 
1336 		err = got_object_open_as_commit(&commit, repo, &qid->id);
1337 		if (err)
1338 			break;
1339 
1340 		parents = got_object_commit_get_parent_ids(commit);
1341 		if (parents) {
1342 			struct got_object_qid *pid;
1343 			color = *((int *)qid->data);
1344 			STAILQ_FOREACH(pid, parents, entry) {
1345 				err = queue_commit_id(ids, &pid->id, color,
1346 				    repo);
1347 				if (err)
1348 					break;
1349 				nqueued++;
1350 				if (color == COLOR_SKIP)
1351 					nskip++;
1352 			}
1353 		}
1354 
1355 		got_object_commit_close(commit);
1356 		commit = NULL;
1357 		got_object_qid_free(qid);
1358 	}
1359 done:
1360 	if (commit)
1361 		got_object_commit_close(commit);
1362 	return err;
1363 }
1364 
1365 static const struct got_error *
1366 findtwixt(struct got_object_id ***res, int *nres, int *ncolored,
1367     struct got_object_id **head, int nhead,
1368     struct got_object_id **tail, int ntail,
1369     struct got_repository *repo,
1370     got_pack_progress_cb progress_cb, void *progress_arg,
1371     struct got_ratelimit *rl, got_cancel_cb cancel_cb, void *cancel_arg)
1372 {
1373 	const struct got_error *err = NULL;
1374 	struct got_object_id_queue ids;
1375 	struct got_object_idset *keep, *drop, *skip = NULL;
1376 	int i, nkeep;
1377 
1378 	STAILQ_INIT(&ids);
1379 	*res = NULL;
1380 	*nres = 0;
1381 	*ncolored = 0;
1382 
1383 	keep = got_object_idset_alloc();
1384 	if (keep == NULL)
1385 		return got_error_from_errno("got_object_idset_alloc");
1386 
1387 	drop = got_object_idset_alloc();
1388 	if (drop == NULL) {
1389 		err = got_error_from_errno("got_object_idset_alloc");
1390 		goto done;
1391 	}
1392 
1393 	skip = got_object_idset_alloc();
1394 	if (skip == NULL) {
1395 		err = got_error_from_errno("got_object_idset_alloc");
1396 		goto done;
1397 	}
1398 
1399 	for (i = 0; i < nhead; i++) {
1400 		struct got_object_id *id = head[i];
1401 		if (id == NULL)
1402 			continue;
1403 		err = queue_commit_or_tag_id(id, COLOR_KEEP, &ids, repo);
1404 		if (err)
1405 			goto done;
1406 	}		
1407 
1408 	for (i = 0; i < ntail; i++) {
1409 		struct got_object_id *id = tail[i];
1410 		if (id == NULL)
1411 			continue;
1412 		err = queue_commit_or_tag_id(id, COLOR_DROP, &ids, repo);
1413 		if (err)
1414 			goto done;
1415 	}
1416 
1417 	err = paint_commits(ncolored, &ids, nhead + ntail,
1418 	    keep, drop, skip, repo, progress_cb, progress_arg, rl,
1419 	    cancel_cb, cancel_arg);
1420 	if (err)
1421 		goto done;
1422 
1423 	nkeep = got_object_idset_num_elements(keep);
1424 	if (nkeep > 0) {
1425 		struct append_id_arg arg;
1426 		arg.array = calloc(nkeep, sizeof(struct got_object_id *));
1427 		if (arg.array == NULL) {
1428 			err = got_error_from_errno("calloc");
1429 			goto done;
1430 		}
1431 		arg.idx = -1;
1432 		arg.skip = skip;
1433 		arg.drop = drop;
1434 		err = got_object_idset_for_each(keep, append_id, &arg);
1435 		if (err) {
1436 			free(arg.array);
1437 			goto done;
1438 		}
1439 		*res = arg.array;
1440 		*nres = arg.idx + 1;
1441 	}
1442 done:
1443 	got_object_idset_free(keep);
1444 	got_object_idset_free(drop);
1445 	if (skip)
1446 		got_object_idset_free(skip);
1447 	got_object_id_queue_free(&ids);
1448 	return err;
1449 }
1450 
1451 static const struct got_error *
1452 load_object_ids(int *ncolored, int *nfound, int *ntrees,
1453     struct got_object_idset *idset, struct got_object_id **theirs, int ntheirs,
1454     struct got_object_id **ours, int nours, struct got_repository *repo,
1455     uint32_t seed, int loose_obj_only, got_pack_progress_cb progress_cb,
1456     void *progress_arg, struct got_ratelimit *rl, got_cancel_cb cancel_cb,
1457     void *cancel_arg)
1458 {
1459 	const struct got_error *err = NULL;
1460 	struct got_object_id **ids = NULL;
1461 	int i, nobj = 0, obj_type;
1462 	struct got_object_idset *idset_exclude;
1463 
1464 	idset_exclude = got_object_idset_alloc();
1465 	if (idset_exclude == NULL)
1466 		return got_error_from_errno("got_object_idset_alloc");
1467 
1468 	*ncolored = 0;
1469 	*nfound = 0;
1470 	*ntrees = 0;
1471 
1472 	err = findtwixt(&ids, &nobj, ncolored, ours, nours, theirs, ntheirs,
1473 	    repo, progress_cb, progress_arg, rl, cancel_cb, cancel_arg);
1474 	if (err)
1475 		goto done;
1476 
1477 	for (i = 0; i < ntheirs; i++) {
1478 		struct got_object_id *id = theirs[i];
1479 		if (id == NULL)
1480 			continue;
1481 		err = got_object_get_type(&obj_type, repo, id);
1482 		if (err)
1483 			return err;
1484 		if (obj_type == GOT_OBJ_TYPE_COMMIT) {
1485 			err = load_commit(0, idset, idset_exclude, id, repo,
1486 			    seed, loose_obj_only, ncolored, nfound, ntrees,
1487 			    progress_cb, progress_arg, rl,
1488 			    cancel_cb, cancel_arg);
1489 			if (err)
1490 				goto done;
1491 		} else if (obj_type == GOT_OBJ_TYPE_TAG) {
1492 			err = load_tag(0, idset, idset_exclude, id, repo,
1493 			    seed, loose_obj_only, ncolored, nfound, ntrees,
1494 			    progress_cb, progress_arg, rl,
1495 			    cancel_cb, cancel_arg);
1496 			if (err)
1497 				goto done;
1498 		}
1499 	}
1500 
1501 	for (i = 0; i < nobj; i++) {
1502 		err = load_commit(1, idset, idset_exclude, ids[i], repo,
1503 		    seed, loose_obj_only, ncolored, nfound, ntrees,
1504 		    progress_cb, progress_arg, rl, cancel_cb, cancel_arg);
1505 		if (err)
1506 			goto done;
1507 	}
1508 
1509 	for (i = 0; i < nours; i++) {
1510 		struct got_object_id *id = ours[i];
1511 		struct got_pack_meta *m;
1512 		if (id == NULL)
1513 			continue;
1514 		m = got_object_idset_get(idset, id);
1515 		if (m == NULL) {
1516 			err = got_object_get_type(&obj_type, repo, id);
1517 			if (err)
1518 				goto done;
1519 		} else
1520 			obj_type = m->obj_type;
1521 		if (obj_type != GOT_OBJ_TYPE_TAG)
1522 			continue;
1523 		err = load_tag(1, idset, idset_exclude, id, repo,
1524 		    seed, loose_obj_only, ncolored, nfound, ntrees,
1525 		    progress_cb, progress_arg, rl, cancel_cb, cancel_arg);
1526 		if (err)
1527 			goto done;
1528 	}
1529 done:
1530 	for (i = 0; i < nobj; i++) {
1531 		free(ids[i]);
1532 	}
1533 	free(ids);
1534 	got_object_idset_free(idset_exclude);
1535 	return err;
1536 }
1537 
1538 const struct got_error *
1539 hwrite(FILE *f, void *buf, off_t len, SHA1_CTX *ctx)
1540 {
1541 	size_t n;
1542 
1543 	SHA1Update(ctx, buf, len);
1544 	n = fwrite(buf, 1, len, f);
1545 	if (n != len)
1546 		return got_ferror(f, GOT_ERR_IO);
1547 	return NULL;
1548 }
1549 
1550 const struct got_error *
1551 hcopy(FILE *fsrc, FILE *fdst, off_t len, SHA1_CTX *ctx)
1552 {
1553 	unsigned char buf[65536];
1554 	off_t remain = len;
1555 	size_t n;
1556 
1557 	while (remain > 0) {
1558 		size_t copylen = MIN(sizeof(buf), remain);
1559 		n = fread(buf, 1, copylen, fsrc);
1560 		if (n != copylen)
1561 			return got_ferror(fsrc, GOT_ERR_IO);
1562 		SHA1Update(ctx, buf, copylen);
1563 		n = fwrite(buf, 1, copylen, fdst);
1564 		if (n != copylen)
1565 			return got_ferror(fdst, GOT_ERR_IO);
1566 		remain -= copylen;
1567 	}
1568 
1569 	return NULL;
1570 }
1571 
1572 const struct got_error *
1573 hcopy_mmap(uint8_t *src, off_t src_offset, size_t src_size,
1574     FILE *fdst, off_t len, SHA1_CTX *ctx)
1575 {
1576 	size_t n;
1577 
1578 	if (src_offset + len > src_size)
1579 		return got_error(GOT_ERR_RANGE);
1580 
1581 	SHA1Update(ctx, src + src_offset, len);
1582 	n = fwrite(src + src_offset, 1, len, fdst);
1583 	if (n != len)
1584 		return got_ferror(fdst, GOT_ERR_IO);
1585 
1586 	return NULL;
1587 }
1588 
1589 static void
1590 putbe32(char *b, uint32_t n)
1591 {
1592 	b[0] = n >> 24;
1593 	b[1] = n >> 16;
1594 	b[2] = n >> 8;
1595 	b[3] = n >> 0;
1596 }
1597 
1598 static int
1599 write_order_cmp(const void *pa, const void *pb)
1600 {
1601 	struct got_pack_meta *a, *b, *ahd, *bhd;
1602 
1603 	a = *(struct got_pack_meta **)pa;
1604 	b = *(struct got_pack_meta **)pb;
1605 	ahd = (a->head == NULL) ? a : a->head;
1606 	bhd = (b->head == NULL) ? b : b->head;
1607 	if (bhd->mtime < ahd->mtime)
1608 		return -1;
1609 	if (bhd->mtime > ahd->mtime)
1610 		return 1;
1611 	if (bhd < ahd)
1612 		return -1;
1613 	if (bhd > ahd)
1614 		return 1;
1615 	if (a->nchain != b->nchain)
1616 		return a->nchain - b->nchain;
1617 	if (a->mtime < b->mtime)
1618 		return -1;
1619 	if (a->mtime > b->mtime)
1620 		return 1;
1621 	return got_object_id_cmp(&a->id, &b->id);
1622 }
1623 
1624 static int
1625 reuse_write_order_cmp(const void *pa, const void *pb)
1626 {
1627 	struct got_pack_meta *a, *b;
1628 
1629 	a = *(struct got_pack_meta **)pa;
1630 	b = *(struct got_pack_meta **)pb;
1631 
1632 	if (a->reused_delta_offset < b->reused_delta_offset)
1633 		return -1;
1634 	if (a->reused_delta_offset > b->reused_delta_offset)
1635 		return 1;
1636 	return 0;
1637 }
1638 
1639 static const struct got_error *
1640 packhdr(int *hdrlen, char *hdr, size_t bufsize, int obj_type, size_t len)
1641 {
1642 	size_t i;
1643 
1644 	*hdrlen = 0;
1645 
1646 	hdr[0] = obj_type << 4;
1647 	hdr[0] |= len & 0xf;
1648 	len >>= 4;
1649 	for (i = 1; len != 0; i++){
1650 		if (i >= bufsize)
1651 			return got_error(GOT_ERR_NO_SPACE);
1652 		hdr[i - 1] |= GOT_DELTA_SIZE_MORE;
1653 		hdr[i] = len & GOT_DELTA_SIZE_VAL_MASK;
1654 		len >>= GOT_DELTA_SIZE_SHIFT;
1655 	}
1656 
1657 	*hdrlen = i;
1658 	return NULL;
1659 }
1660 
1661 static int
1662 packoff(char *hdr, off_t off)
1663 {
1664 	int i, j;
1665 	char rbuf[8];
1666 
1667 	rbuf[0] = off & GOT_DELTA_SIZE_VAL_MASK;
1668 	for (i = 1; (off >>= GOT_DELTA_SIZE_SHIFT) != 0; i++) {
1669 		rbuf[i] = (--off & GOT_DELTA_SIZE_VAL_MASK) |
1670 		    GOT_DELTA_SIZE_MORE;
1671 	}
1672 
1673 	j = 0;
1674 	while (i > 0)
1675 		hdr[j++] = rbuf[--i];
1676 	return j;
1677 }
1678 
1679 static const struct got_error *
1680 deltahdr(off_t *packfile_size, SHA1_CTX *ctx, FILE *packfile,
1681     struct got_pack_meta *m)
1682 {
1683 	const struct got_error *err;
1684 	char buf[32];
1685 	int nh;
1686 
1687 	if (m->prev->off != 0) {
1688 		err = packhdr(&nh, buf, sizeof(buf),
1689 		    GOT_OBJ_TYPE_OFFSET_DELTA, m->delta_len);
1690 		if (err)
1691 			return err;
1692 		nh += packoff(buf + nh, m->off - m->prev->off);
1693 		err = hwrite(packfile, buf, nh, ctx);
1694 		if (err)
1695 			return err;
1696 		*packfile_size += nh;
1697 	} else {
1698 		err = packhdr(&nh, buf, sizeof(buf),
1699 		    GOT_OBJ_TYPE_REF_DELTA, m->delta_len);
1700 		if (err)
1701 			return err;
1702 		err = hwrite(packfile, buf, nh, ctx);
1703 		if (err)
1704 			return err;
1705 		*packfile_size += nh;
1706 		err = hwrite(packfile, m->prev->id.sha1,
1707 		    sizeof(m->prev->id.sha1), ctx);
1708 		if (err)
1709 			return err;
1710 		*packfile_size += sizeof(m->prev->id.sha1);
1711 	}
1712 
1713 	return NULL;
1714 }
1715 
1716 static const struct got_error *
1717 write_packed_object(off_t *packfile_size, FILE *packfile,
1718     FILE *delta_cache, uint8_t *delta_cache_map, size_t delta_cache_size,
1719     struct got_pack_meta *m, int *outfd, SHA1_CTX *ctx,
1720     struct got_repository *repo)
1721 {
1722 	const struct got_error *err = NULL;
1723 	struct got_deflate_checksum csum;
1724 	char buf[32];
1725 	int nh;
1726 	struct got_raw_object *raw = NULL;
1727 	off_t outlen;
1728 
1729 	csum.output_sha1 = ctx;
1730 	csum.output_crc = NULL;
1731 
1732 	m->off = ftello(packfile);
1733 	if (m->delta_len == 0) {
1734 		err = got_object_raw_open(&raw, outfd, repo, &m->id);
1735 		if (err)
1736 			goto done;
1737 		err = packhdr(&nh, buf, sizeof(buf),
1738 		    m->obj_type, raw->size);
1739 		if (err)
1740 			goto done;
1741 		err = hwrite(packfile, buf, nh, ctx);
1742 		if (err)
1743 			goto done;
1744 		*packfile_size += nh;
1745 		if (raw->f == NULL) {
1746 			err = got_deflate_to_file_mmap(&outlen,
1747 			    raw->data + raw->hdrlen, 0, raw->size,
1748 			    packfile, &csum);
1749 			if (err)
1750 				goto done;
1751 		} else {
1752 			if (fseeko(raw->f, raw->hdrlen, SEEK_SET)
1753 			    == -1) {
1754 				err = got_error_from_errno("fseeko");
1755 				goto done;
1756 			}
1757 			err = got_deflate_to_file(&outlen, raw->f,
1758 			    raw->size, packfile, &csum);
1759 			if (err)
1760 				goto done;
1761 		}
1762 		*packfile_size += outlen;
1763 		got_object_raw_close(raw);
1764 		raw = NULL;
1765 	} else if (m->delta_buf) {
1766 		err = deltahdr(packfile_size, ctx, packfile, m);
1767 		if (err)
1768 			goto done;
1769 		err = hwrite(packfile, m->delta_buf,
1770 		    m->delta_compressed_len, ctx);
1771 		if (err)
1772 			goto done;
1773 		*packfile_size += m->delta_compressed_len;
1774 		free(m->delta_buf);
1775 		m->delta_buf = NULL;
1776 	} else if (delta_cache_map) {
1777 		err = deltahdr(packfile_size, ctx, packfile, m);
1778 		if (err)
1779 			goto done;
1780 		err = hcopy_mmap(delta_cache_map, m->delta_offset,
1781 		    delta_cache_size, packfile, m->delta_compressed_len,
1782 		    ctx);
1783 		if (err)
1784 			goto done;
1785 		*packfile_size += m->delta_compressed_len;
1786 	} else {
1787 		if (fseeko(delta_cache, m->delta_offset, SEEK_SET)
1788 		    == -1) {
1789 			err = got_error_from_errno("fseeko");
1790 			goto done;
1791 		}
1792 		err = deltahdr(packfile_size, ctx, packfile, m);
1793 		if (err)
1794 			goto done;
1795 		err = hcopy(delta_cache, packfile,
1796 		    m->delta_compressed_len, ctx);
1797 		if (err)
1798 			goto done;
1799 		*packfile_size += m->delta_compressed_len;
1800 	}
1801 done:
1802 	if (raw)
1803 		got_object_raw_close(raw);
1804 	return err;
1805 }
1806 
1807 static const struct got_error *
1808 genpack(uint8_t *pack_sha1, FILE *packfile, FILE *delta_cache,
1809     struct got_pack_meta **deltify, int ndeltify,
1810     struct got_pack_meta **reuse, int nreuse,
1811     int ncolored, int nfound, int ntrees, int nours,
1812     struct got_repository *repo,
1813     got_pack_progress_cb progress_cb, void *progress_arg,
1814     struct got_ratelimit *rl,
1815     got_cancel_cb cancel_cb, void *cancel_arg)
1816 {
1817 	const struct got_error *err = NULL;
1818 	int i;
1819 	SHA1_CTX ctx;
1820 	struct got_pack_meta *m;
1821 	char buf[32];
1822 	size_t n;
1823 	off_t packfile_size = 0;
1824 	int outfd = -1;
1825 	int delta_cache_fd = -1;
1826 	uint8_t *delta_cache_map = NULL;
1827 	size_t delta_cache_size = 0;
1828 
1829 	SHA1Init(&ctx);
1830 
1831 #ifndef GOT_PACK_NO_MMAP
1832 	delta_cache_fd = dup(fileno(delta_cache));
1833 	if (delta_cache_fd != -1) {
1834 		struct stat sb;
1835 		if (fstat(delta_cache_fd, &sb) == -1) {
1836 			err = got_error_from_errno("fstat");
1837 			goto done;
1838 		}
1839 		if (sb.st_size > 0 && sb.st_size <= SIZE_MAX) {
1840 			delta_cache_map = mmap(NULL, sb.st_size,
1841 			    PROT_READ, MAP_PRIVATE, delta_cache_fd, 0);
1842 			if (delta_cache_map == MAP_FAILED) {
1843 				if (errno != ENOMEM) {
1844 					err = got_error_from_errno("mmap");
1845 					goto done;
1846 				}
1847 				delta_cache_map = NULL; /* fallback on stdio */
1848 			} else
1849 				delta_cache_size = (size_t)sb.st_size;
1850 		}
1851 	}
1852 #endif
1853 	err = hwrite(packfile, "PACK", 4, &ctx);
1854 	if (err)
1855 		goto done;
1856 	putbe32(buf, GOT_PACKFILE_VERSION);
1857 	err = hwrite(packfile, buf, 4, &ctx);
1858 	if (err)
1859 		goto done;
1860 	putbe32(buf, ndeltify + nreuse);
1861 	err = hwrite(packfile, buf, 4, &ctx);
1862 	if (err)
1863 		goto done;
1864 
1865 	qsort(deltify, ndeltify, sizeof(struct got_pack_meta *),
1866 	    write_order_cmp);
1867 	for (i = 0; i < ndeltify; i++) {
1868 		err = report_progress(progress_cb, progress_arg, rl,
1869 		    ncolored, nfound, ntrees, packfile_size, nours,
1870 		    ndeltify + nreuse, ndeltify + nreuse, i);
1871 		if (err)
1872 			goto done;
1873 		m = deltify[i];
1874 		err = write_packed_object(&packfile_size, packfile,
1875 		    delta_cache, delta_cache_map, delta_cache_size,
1876 		    m, &outfd, &ctx, repo);
1877 		if (err)
1878 			goto done;
1879 	}
1880 
1881 	qsort(reuse, nreuse, sizeof(struct got_pack_meta *),
1882 	    reuse_write_order_cmp);
1883 	for (i = 0; i < nreuse; i++) {
1884 		err = report_progress(progress_cb, progress_arg, rl,
1885 		    ncolored, nfound, ntrees, packfile_size, nours,
1886 		    ndeltify + nreuse, ndeltify + nreuse, ndeltify + i);
1887 		if (err)
1888 			goto done;
1889 		m = reuse[i];
1890 		err = write_packed_object(&packfile_size, packfile,
1891 		    delta_cache, delta_cache_map, delta_cache_size,
1892 		    m, &outfd, &ctx, repo);
1893 		if (err)
1894 			goto done;
1895 	}
1896 
1897 	SHA1Final(pack_sha1, &ctx);
1898 	n = fwrite(pack_sha1, 1, SHA1_DIGEST_LENGTH, packfile);
1899 	if (n != SHA1_DIGEST_LENGTH)
1900 		err = got_ferror(packfile, GOT_ERR_IO);
1901 	packfile_size += SHA1_DIGEST_LENGTH;
1902 	packfile_size += sizeof(struct got_packfile_hdr);
1903 	if (progress_cb) {
1904 		err = progress_cb(progress_arg, ncolored, nfound, ntrees,
1905 		    packfile_size, nours, ndeltify + nreuse,
1906 		    ndeltify + nreuse, ndeltify + nreuse);
1907 		if (err)
1908 			goto done;
1909 	}
1910 done:
1911 	if (outfd != -1 && close(outfd) == -1 && err == NULL)
1912 		err = got_error_from_errno("close");
1913 	if (delta_cache_map && munmap(delta_cache_map, delta_cache_size) == -1)
1914 		err = got_error_from_errno("munmap");
1915 	if (delta_cache_fd != -1 && close(delta_cache_fd) == -1 && err == NULL)
1916 		err = got_error_from_errno("close");
1917 	return err;
1918 }
1919 
1920 static const struct got_error *
1921 add_meta_idset_cb(struct got_object_id *id, void *data, void *arg)
1922 {
1923 	struct got_pack_meta *m = data;
1924 	struct got_pack_metavec *v = arg;
1925 
1926 	if (m->reused_delta_offset != 0)
1927 		return NULL;
1928 
1929 	return add_meta(m, v);
1930 }
1931 
1932 const struct got_error *
1933 got_pack_create(uint8_t *packsha1, FILE *packfile,
1934     struct got_object_id **theirs, int ntheirs,
1935     struct got_object_id **ours, int nours,
1936     struct got_repository *repo, int loose_obj_only, int allow_empty,
1937     got_pack_progress_cb progress_cb, void *progress_arg,
1938     got_cancel_cb cancel_cb, void *cancel_arg)
1939 {
1940 	const struct got_error *err;
1941 	int delta_cache_fd = -1;
1942 	FILE *delta_cache = NULL;
1943 	struct got_object_idset *idset;
1944 	struct got_ratelimit rl;
1945 	struct got_pack_metavec deltify, reuse;
1946 	int ncolored = 0, nfound = 0, ntrees = 0;
1947 	size_t ndeltify;
1948 	uint32_t seed;
1949 
1950 	seed = arc4random();
1951 
1952 	memset(&deltify, 0, sizeof(deltify));
1953 	memset(&reuse, 0, sizeof(reuse));
1954 
1955 	got_ratelimit_init(&rl, 0, 500);
1956 
1957 	idset = got_object_idset_alloc();
1958 	if (idset == NULL)
1959 		return got_error_from_errno("got_object_idset_alloc");
1960 
1961 	err = load_object_ids(&ncolored, &nfound, &ntrees, idset, theirs,
1962 	    ntheirs, ours, nours, repo, seed, loose_obj_only,
1963 	    progress_cb, progress_arg, &rl, cancel_cb, cancel_arg);
1964 	if (err)
1965 		goto done;
1966 
1967 	if (progress_cb) {
1968 		err = progress_cb(progress_arg, ncolored, nfound, ntrees,
1969 		    0L, nours, got_object_idset_num_elements(idset), 0, 0);
1970 		if (err)
1971 			goto done;
1972 	}
1973 
1974 	if (got_object_idset_num_elements(idset) == 0 && !allow_empty) {
1975 		err = got_error(GOT_ERR_CANNOT_PACK);
1976 		goto done;
1977 	}
1978 
1979 	delta_cache_fd = got_opentempfd();
1980 	if (delta_cache_fd == -1) {
1981 		err = got_error_from_errno("got_opentemp");
1982 		goto done;
1983 	}
1984 
1985 	reuse.metasz = 64;
1986 	reuse.meta = calloc(reuse.metasz,
1987 	    sizeof(struct got_pack_meta *));
1988 	if (reuse.meta == NULL) {
1989 		err = got_error_from_errno("calloc");
1990 		goto done;
1991 	}
1992 
1993 	err = search_deltas(&reuse, idset, delta_cache_fd, ncolored, nfound,
1994 	    ntrees, nours, repo, progress_cb, progress_arg, &rl,
1995 	    cancel_cb, cancel_arg);
1996 	if (err)
1997 		goto done;
1998 
1999 	delta_cache = fdopen(delta_cache_fd, "a+");
2000 	if (delta_cache == NULL) {
2001 		err = got_error_from_errno("fdopen");
2002 		goto done;
2003 	}
2004 	delta_cache_fd = -1;
2005 
2006 	if (fseeko(delta_cache, 0L, SEEK_END) == -1) {
2007 		err = got_error_from_errno("fseeko");
2008 		goto done;
2009 	}
2010 
2011 	ndeltify = got_object_idset_num_elements(idset) - reuse.nmeta;
2012 	if (ndeltify > 0) {
2013 		deltify.meta = calloc(ndeltify, sizeof(struct got_pack_meta *));
2014 		if (deltify.meta == NULL) {
2015 			err = got_error_from_errno("calloc");
2016 			goto done;
2017 		}
2018 		deltify.metasz = ndeltify;
2019 
2020 		err = got_object_idset_for_each(idset, add_meta_idset_cb,
2021 		    &deltify);
2022 		if (err)
2023 			goto done;
2024 		if (deltify.nmeta > 0) {
2025 			err = pick_deltas(deltify.meta, deltify.nmeta,
2026 			    ncolored, nfound, ntrees, nours, reuse.nmeta,
2027 			    delta_cache, repo, progress_cb, progress_arg, &rl,
2028 			    cancel_cb, cancel_arg);
2029 			if (err)
2030 				goto done;
2031 		}
2032 	}
2033 
2034 	if (fflush(delta_cache) == EOF) {
2035 		err = got_error_from_errno("fflush");
2036 		goto done;
2037 	}
2038 	err = genpack(packsha1, packfile, delta_cache, deltify.meta,
2039 	    deltify.nmeta, reuse.meta, reuse.nmeta, ncolored, nfound, ntrees,
2040 	    nours, repo, progress_cb, progress_arg, &rl,
2041 	    cancel_cb, cancel_arg);
2042 	if (err)
2043 		goto done;
2044 done:
2045 	free_nmeta(deltify.meta, deltify.nmeta);
2046 	free_nmeta(reuse.meta, reuse.nmeta);
2047 	got_object_idset_free(idset);
2048 	if (delta_cache_fd != -1 && close(delta_cache_fd) == -1 && err == NULL)
2049 		err = got_error_from_errno("close");
2050 	if (delta_cache && fclose(delta_cache) == EOF && err == NULL)
2051 		err = got_error_from_errno("fclose");
2052 	return err;
2053 }