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Date:: Fri Jul 1 21:13:24 2022 UTC
Message:: move got_opentempfd out of open_blob. ok stsp@
Actions:: History | Blame | Raw File
1 /*
2  * Copyright (c) 2022 Omar Polo <op@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  * Apply patches.
17  *
18  * Things that we may want to support:
19  *     + support indented patches?
20  *     + support other kinds of patches?
21  */
22 
23 #include <sys/types.h>
24 #include <sys/socket.h>
25 #include <sys/stat.h>
26 #include <sys/uio.h>
27 
28 #include <errno.h>
29 #include <limits.h>
30 #include <stdint.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <unistd.h>
35 
36 #include "got_error.h"
37 #include "got_object.h"
38 #include "got_path.h"
39 #include "got_reference.h"
40 #include "got_cancel.h"
41 #include "got_worktree.h"
42 #include "got_repository.h"
43 #include "got_opentemp.h"
44 #include "got_patch.h"
45 
46 #include "got_lib_delta.h"
47 #include "got_lib_diff.h"
48 #include "got_lib_object.h"
49 #include "got_lib_privsep.h"
50 #include "got_lib_sha1.h"
51 
52 #define MIN(a, b) ((a) < (b) ? (a) : (b))
53 
54 struct got_patch_hunk {
55 	STAILQ_ENTRY(got_patch_hunk) entries;
56 	const struct got_error *err;
57 	int	offset;
58 	int	old_nonl;
59 	int	new_nonl;
60 	int	old_from;
61 	int	old_lines;
62 	int	new_from;
63 	int	new_lines;
64 	size_t	len;
65 	size_t	cap;
66 	char	**lines;
67 };
68 
69 STAILQ_HEAD(got_patch_hunk_head, got_patch_hunk);
70 struct got_patch {
71 	char	*old;
72 	char	*new;
73 	char	 cid[41];
74 	char	 blob[41];
75 	struct got_patch_hunk_head head;
76 };
77 
78 struct patch_args {
79 	got_patch_progress_cb progress_cb;
80 	void	*progress_arg;
81 	struct got_patch_hunk_head *head;
82 };
83 
84 static const struct got_error *
85 send_patch(struct imsgbuf *ibuf, int fd)
86 {
87 	const struct got_error *err = NULL;
88 
89 	if (imsg_compose(ibuf, GOT_IMSG_PATCH_FILE, 0, 0, fd,
90 	    NULL, 0) == -1) {
91 		err = got_error_from_errno(
92 		    "imsg_compose GOT_IMSG_PATCH_FILE");
93 		close(fd);
94 		return err;
95 	}
96 
97 	if (imsg_flush(ibuf) == -1) {
98 		err = got_error_from_errno("imsg_flush");
99 		imsg_clear(ibuf);
100 	}
101 
102 	return err;
103 }
104 
105 static void
106 patch_free(struct got_patch *p)
107 {
108 	struct got_patch_hunk *h;
109 	size_t i;
110 
111 	while (!STAILQ_EMPTY(&p->head)) {
112 		h = STAILQ_FIRST(&p->head);
113 		STAILQ_REMOVE_HEAD(&p->head, entries);
114 
115 		for (i = 0; i < h->len; ++i)
116 			free(h->lines[i]);
117 		free(h->lines);
118 		free(h);
119 	}
120 
121 	free(p->new);
122 	free(p->old);
123 
124 	memset(p, 0, sizeof(*p));
125 	STAILQ_INIT(&p->head);
126 }
127 
128 static const struct got_error *
129 pushline(struct got_patch_hunk *h, const char *line)
130 {
131 	void 	*t;
132 	size_t	 newcap;
133 
134 	if (h->len == h->cap) {
135 		if ((newcap = h->cap * 1.5) == 0)
136 			newcap = 16;
137 		t = recallocarray(h->lines, h->cap, newcap,
138 		    sizeof(h->lines[0]));
139 		if (t == NULL)
140 			return got_error_from_errno("recallocarray");
141 		h->lines = t;
142 		h->cap = newcap;
143 	}
144 
145 	if ((t = strdup(line)) == NULL)
146 		return got_error_from_errno("strdup");
147 
148 	h->lines[h->len++] = t;
149 	return NULL;
150 }
151 
152 static const struct got_error *
153 recv_patch(struct imsgbuf *ibuf, int *done, struct got_patch *p, int strip)
154 {
155 	const struct got_error *err = NULL;
156 	struct imsg imsg;
157 	struct got_imsg_patch_hunk hdr;
158 	struct got_imsg_patch patch;
159 	struct got_patch_hunk *h = NULL;
160 	size_t datalen;
161 	int lastmode = -1;
162 
163 	memset(p, 0, sizeof(*p));
164 	STAILQ_INIT(&p->head);
165 
166 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
167 	if (err)
168 		return err;
169 	if (imsg.hdr.type == GOT_IMSG_PATCH_EOF) {
170 		*done = 1;
171 		goto done;
172 	}
173 	if (imsg.hdr.type != GOT_IMSG_PATCH) {
174 		err = got_error(GOT_ERR_PRIVSEP_MSG);
175 		goto done;
176 	}
177 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
178 	if (datalen != sizeof(patch)) {
179 		err = got_error(GOT_ERR_PRIVSEP_LEN);
180 		goto done;
181 	}
182 	memcpy(&patch, imsg.data, sizeof(patch));
183 
184 	if (patch.old[sizeof(patch.old)-1] != '\0' ||
185 	    patch.new[sizeof(patch.new)-1] != '\0' ||
186 	    patch.cid[sizeof(patch.cid)-1] != '\0' ||
187 	    patch.blob[sizeof(patch.blob)-1] != '\0') {
188 		err = got_error(GOT_ERR_PRIVSEP_LEN);
189 		goto done;
190 	}
191 
192 	if (*patch.cid != '\0')
193 		strlcpy(p->cid, patch.cid, sizeof(p->cid));
194 
195 	if (*patch.blob != '\0')
196 		strlcpy(p->blob, patch.blob, sizeof(p->blob));
197 
198 	/* automatically set strip=1 for git-style diffs */
199 	if (strip == -1 && patch.git &&
200 	    (*patch.old == '\0' || !strncmp(patch.old, "a/", 2)) &&
201 	    (*patch.new == '\0' || !strncmp(patch.new, "b/", 2)))
202 		strip = 1;
203 
204 	/* prefer the new name if not /dev/null for not git-style diffs */
205 	if (!patch.git && *patch.new != '\0' && *patch.old != '\0') {
206 		err = got_path_strip(&p->old, patch.new, strip);
207 		if (err)
208 			goto done;
209 	} else if (*patch.old != '\0') {
210 		err = got_path_strip(&p->old, patch.old, strip);
211 		if (err)
212 			goto done;
213 	}
214 
215 	if (*patch.new != '\0') {
216 		err = got_path_strip(&p->new, patch.new, strip);
217 		if (err)
218 			goto done;
219 	}
220 
221 	if (p->old == NULL && p->new == NULL) {
222 		err = got_error(GOT_ERR_PATCH_MALFORMED);
223 		goto done;
224 	}
225 
226 	imsg_free(&imsg);
227 
228 	for (;;) {
229 		char *t;
230 
231 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
232 		if (err) {
233 			patch_free(p);
234 			return err;
235 		}
236 
237 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
238 		switch (imsg.hdr.type) {
239 		case GOT_IMSG_PATCH_DONE:
240 			if (h != NULL && h->len == 0)
241 				err = got_error(GOT_ERR_PATCH_MALFORMED);
242 			goto done;
243 		case GOT_IMSG_PATCH_HUNK:
244 			if (h != NULL &&
245 			    (h->len == 0 || h->old_nonl || h->new_nonl)) {
246 				err = got_error(GOT_ERR_PATCH_MALFORMED);
247 				goto done;
248 			}
249 			lastmode = -1;
250 			if (datalen != sizeof(hdr)) {
251 				err = got_error(GOT_ERR_PRIVSEP_LEN);
252 				goto done;
253 			}
254 			memcpy(&hdr, imsg.data, sizeof(hdr));
255 			if (hdr.oldfrom < 0 || hdr.newfrom < 0) {
256 				err = got_error(GOT_ERR_PRIVSEP_LEN);
257 				goto done;
258 			}
259 			if ((h = calloc(1, sizeof(*h))) == NULL) {
260 				err = got_error_from_errno("calloc");
261 				goto done;
262 			}
263 			h->old_from = hdr.oldfrom;
264 			h->old_lines = hdr.oldlines;
265 			h->new_from = hdr.newfrom;
266 			h->new_lines = hdr.newlines;
267 			STAILQ_INSERT_TAIL(&p->head, h, entries);
268 			break;
269 		case GOT_IMSG_PATCH_LINE:
270 			if (h == NULL) {
271 				err = got_error(GOT_ERR_PRIVSEP_MSG);
272 				goto done;
273 			}
274 			t = imsg.data;
275 			/* at least one char */
276 			if (datalen < 2 || t[datalen-1] != '\0') {
277 				err = got_error(GOT_ERR_PRIVSEP_MSG);
278 				goto done;
279 			}
280 			if (*t != ' ' && *t != '-' && *t != '+' &&
281 			    *t != '\\') {
282 				err = got_error(GOT_ERR_PRIVSEP_MSG);
283 				goto done;
284 			}
285 
286 			if (*t != '\\')
287 				err = pushline(h, t);
288 			else if (lastmode == '-')
289 				h->old_nonl = 1;
290 			else if (lastmode == '+')
291 				h->new_nonl = 1;
292 			else
293 				err = got_error(GOT_ERR_PATCH_MALFORMED);
294 
295 			if (err)
296 				goto done;
297 
298 			lastmode = *t;
299 			break;
300 		default:
301 			err = got_error(GOT_ERR_PRIVSEP_MSG);
302 			goto done;
303 		}
304 
305 		imsg_free(&imsg);
306 	}
307 
308 done:
309 	if (err)
310 		patch_free(p);
311 
312 	imsg_free(&imsg);
313 	return err;
314 }
315 
316 /*
317  * Copy data from orig starting at copypos until pos into tmp.
318  * If pos is -1, copy until EOF.
319  */
320 static const struct got_error *
321 copy(FILE *tmp, FILE *orig, off_t copypos, off_t pos)
322 {
323 	char buf[BUFSIZ];
324 	size_t len, r, w;
325 
326 	if (fseeko(orig, copypos, SEEK_SET) == -1)
327 		return got_error_from_errno("fseeko");
328 
329 	while (pos == -1 || copypos < pos) {
330 		len = sizeof(buf);
331 		if (pos > 0)
332 			len = MIN(len, (size_t)pos - copypos);
333 		r = fread(buf, 1, len, orig);
334 		if (r != len && ferror(orig))
335 			return got_error_from_errno("fread");
336 		w = fwrite(buf, 1, r, tmp);
337 		if (w != r)
338 			return got_error_from_errno("fwrite");
339 		copypos += len;
340 		if (r != len && feof(orig)) {
341 			if (pos == -1)
342 				return NULL;
343 			return got_error(GOT_ERR_HUNK_FAILED);
344 		}
345 	}
346 	return NULL;
347 }
348 
349 static const struct got_error *
350 locate_hunk(FILE *orig, struct got_patch_hunk *h, off_t *pos, int *lineno)
351 {
352 	const struct got_error *err = NULL;
353 	char *line = NULL;
354 	char mode = *h->lines[0];
355 	size_t linesize = 0;
356 	ssize_t linelen;
357 	off_t match = -1;
358 	int match_lineno = -1;
359 
360 	for (;;) {
361 		linelen = getline(&line, &linesize, orig);
362 		if (linelen == -1) {
363 			if (ferror(orig))
364 				err = got_error_from_errno("getline");
365 			else if (match == -1)
366 				err = got_error(GOT_ERR_HUNK_FAILED);
367 			break;
368 		}
369 		if (line[linelen - 1] == '\n')
370 			line[linelen - 1] = '\0';
371 		(*lineno)++;
372 
373 		if ((mode == ' ' && !strcmp(h->lines[0] + 1, line)) ||
374 		    (mode == '-' && !strcmp(h->lines[0] + 1, line)) ||
375 		    (mode == '+' && *lineno == h->old_from)) {
376 			match = ftello(orig);
377 			if (match == -1) {
378 				err = got_error_from_errno("ftello");
379 				break;
380 			}
381 			match -= linelen;
382 			match_lineno = (*lineno)-1;
383 		}
384 
385 		if (*lineno >= h->old_from && match != -1)
386 			break;
387 	}
388 
389 	if (err == NULL) {
390 		*pos = match;
391 		*lineno = match_lineno;
392 		if (fseeko(orig, match, SEEK_SET) == -1)
393 			err = got_error_from_errno("fseeko");
394 	}
395 
396 	free(line);
397 	return err;
398 }
399 
400 static const struct got_error *
401 test_hunk(FILE *orig, struct got_patch_hunk *h)
402 {
403 	const struct got_error *err = NULL;
404 	char *line = NULL;
405 	size_t linesize = 0, i = 0;
406 	ssize_t linelen;
407 
408 	for (i = 0; i < h->len; ++i) {
409 		switch (*h->lines[i]) {
410 		case '+':
411 			continue;
412 		case ' ':
413 		case '-':
414 			linelen = getline(&line, &linesize, orig);
415 			if (linelen == -1) {
416 				if (ferror(orig))
417 					err = got_error_from_errno("getline");
418 				else
419 					err = got_error(
420 					    GOT_ERR_HUNK_FAILED);
421 				goto done;
422 			}
423 			if (line[linelen - 1] == '\n')
424 				line[linelen - 1] = '\0';
425 			if (strcmp(h->lines[i] + 1, line)) {
426 				err = got_error(GOT_ERR_HUNK_FAILED);
427 				goto done;
428 			}
429 			break;
430 		}
431 	}
432 
433 done:
434 	free(line);
435 	return err;
436 }
437 
438 static const struct got_error *
439 apply_hunk(FILE *tmp, struct got_patch_hunk *h, int *lineno)
440 {
441 	size_t i, new = 0;
442 
443 	for (i = 0; i < h->len; ++i) {
444 		switch (*h->lines[i]) {
445 		case ' ':
446 			if (fprintf(tmp, "%s\n", h->lines[i] + 1) < 0)
447 				return got_error_from_errno("fprintf");
448 			/* fallthrough */
449 		case '-':
450 			(*lineno)++;
451 			break;
452 		case '+':
453 			new++;
454 			if (fprintf(tmp, "%s", h->lines[i] + 1) < 0)
455 				return got_error_from_errno("fprintf");
456 			if (new != h->new_lines || !h->new_nonl) {
457 				if (fprintf(tmp, "\n") < 0)
458 					return got_error_from_errno(
459 					    "fprintf");
460 			}
461 			break;
462 		}
463 	}
464 	return NULL;
465 }
466 
467 static const struct got_error *
468 patch_file(struct got_patch *p, FILE *orig, FILE *tmp, mode_t *mode)
469 {
470 	const struct got_error *err = NULL;
471 	struct got_patch_hunk *h;
472 	struct stat sb;
473 	int lineno = 0;
474 	off_t copypos, pos;
475 	char *line = NULL;
476 	size_t linesize = 0;
477 	ssize_t linelen;
478 
479 	if (p->old == NULL) {				/* create */
480 		h = STAILQ_FIRST(&p->head);
481 		if (h == NULL || STAILQ_NEXT(h, entries) != NULL)
482 			return got_error(GOT_ERR_PATCH_MALFORMED);
483 		return apply_hunk(tmp, h, &lineno);
484 	}
485 
486 	if (fstat(fileno(orig), &sb) == -1)
487 		return got_error_from_errno("fstat");
488 	*mode = sb.st_mode;
489 
490 	copypos = 0;
491 	STAILQ_FOREACH(h, &p->head, entries) {
492 	tryagain:
493 		err = locate_hunk(orig, h, &pos, &lineno);
494 		if (err != NULL && err->code == GOT_ERR_HUNK_FAILED)
495 			h->err = err;
496 		if (err != NULL)
497 			return err;
498 		err = copy(tmp, orig, copypos, pos);
499 		if (err != NULL)
500 			return err;
501 		copypos = pos;
502 
503 		err = test_hunk(orig, h);
504 		if (err != NULL && err->code == GOT_ERR_HUNK_FAILED) {
505 			/*
506 			 * try to apply the hunk again starting the search
507 			 * after the previous partial match.
508 			 */
509 			if (fseeko(orig, pos, SEEK_SET) == -1)
510 				return got_error_from_errno("fseeko");
511 			linelen = getline(&line, &linesize, orig);
512 			if (linelen == -1)
513 				return got_error_from_errno("getline");
514 			lineno++;
515 			goto tryagain;
516 		}
517 		if (err != NULL)
518 			return err;
519 
520 		if (lineno + 1 != h->old_from)
521 			h->offset = lineno + 1 - h->old_from;
522 
523 		err = apply_hunk(tmp, h, &lineno);
524 		if (err != NULL)
525 			return err;
526 
527 		copypos = ftello(orig);
528 		if (copypos == -1)
529 			return got_error_from_errno("ftello");
530 	}
531 
532 	if (p->new == NULL && sb.st_size != copypos) {
533 		h = STAILQ_FIRST(&p->head);
534 		h->err = got_error(GOT_ERR_HUNK_FAILED);
535 		err = h->err;
536 	} else if (!feof(orig))
537 		err = copy(tmp, orig, copypos, -1);
538 
539 	return err;
540 }
541 
542 static const struct got_error *
543 report_progress(struct patch_args *pa, const char *old, const char *new,
544     unsigned char status, const struct got_error *orig_error)
545 {
546 	const struct got_error *err;
547 	struct got_patch_hunk *h;
548 
549 	err = pa->progress_cb(pa->progress_arg, old, new, status,
550 	    orig_error, 0, 0, 0, 0, 0, NULL);
551 	if (err)
552 		return err;
553 
554 	STAILQ_FOREACH(h, pa->head, entries) {
555 		if (h->offset == 0 && h->err == NULL)
556 			continue;
557 
558 		err = pa->progress_cb(pa->progress_arg, old, new, 0, NULL,
559 		    h->old_from, h->old_lines, h->new_from, h->new_lines,
560 		    h->offset, h->err);
561 		if (err)
562 			return err;
563 	}
564 
565 	return NULL;
566 }
567 
568 static const struct got_error *
569 patch_delete(void *arg, unsigned char status, unsigned char staged_status,
570     const char *path)
571 {
572 	return report_progress(arg, path, NULL, status, NULL);
573 }
574 
575 static const struct got_error *
576 patch_add(void *arg, unsigned char status, const char *path)
577 {
578 	return report_progress(arg, NULL, path, status, NULL);
579 }
580 
581 static const struct got_error *
582 open_blob(char **path, FILE **fp, const char *blobid,
583     struct got_repository *repo)
584 {
585 	const struct got_error *err = NULL;
586 	struct got_blob_object *blob = NULL;
587 	struct got_object_id id, *idptr, *matched_id = NULL;
588 	int fd = -1;
589 
590 	*fp = NULL;
591 	*path = NULL;
592 
593 	if (strlen(blobid) != SHA1_DIGEST_STRING_LENGTH - 1) {
594 		err = got_repo_match_object_id(&matched_id, NULL, blobid,
595 		    GOT_OBJ_TYPE_BLOB, NULL /* do not resolve tags */,
596 		    repo);
597 		if (err)
598 			return err;
599 		idptr = matched_id;
600 	} else {
601 		if (!got_parse_sha1_digest(id.sha1, blobid))
602 			return got_error(GOT_ERR_BAD_OBJ_ID_STR);
603 		idptr = &id;
604 	}
605 
606 	fd = got_opentempfd();
607 	if (fd == -1) {
608 		err = got_error_from_errno("got_opentempfd");
609 		goto done;
610 	}
611 
612 	err = got_object_open_as_blob(&blob, repo, idptr, 8192, fd);
613 	if (err)
614 		goto done;
615 
616 	err = got_opentemp_named(path, fp, GOT_TMPDIR_STR "/got-patch-blob");
617 	if (err)
618 		goto done;
619 
620 	err = got_object_blob_dump_to_file(NULL, NULL, NULL, *fp, blob);
621 	if (err)
622 		goto done;
623 
624 done:
625 	if (fd != -1 && close(fd) == -1 && err == NULL)
626 		err = got_error_from_errno("close");
627 	if (blob)
628 		got_object_blob_close(blob);
629 	if (matched_id != NULL)
630 		free(matched_id);
631 	if (err) {
632 		if (*fp != NULL)
633 			fclose(*fp);
634 		if (*path != NULL)
635 			unlink(*path);
636 		free(*path);
637 		*fp = NULL;
638 		*path = NULL;
639 	}
640 	return err;
641 }
642 
643 static const struct got_error *
644 apply_patch(int *overlapcnt, struct got_worktree *worktree,
645     struct got_repository *repo, struct got_fileindex *fileindex,
646     const char *old, const char *new, struct got_patch *p, int nop,
647     struct patch_args *pa, got_cancel_cb cancel_cb, void *cancel_arg)
648 {
649 	const struct got_error *err = NULL;
650 	int do_merge = 0, file_renamed = 0;
651 	char *oldlabel = NULL, *newlabel = NULL, *anclabel = NULL;
652 	char *oldpath = NULL, *newpath = NULL;
653 	char *tmppath = NULL, *template = NULL, *parent = NULL;
654 	char *apath = NULL, *mergepath = NULL;
655 	FILE *oldfile = NULL, *tmpfile = NULL, *afile = NULL, *mergefile = NULL;
656 	int outfd;
657 	const char *outpath;
658 	mode_t mode = GOT_DEFAULT_FILE_MODE;
659 
660 	*overlapcnt = 0;
661 
662 	/* don't run the diff3 merge on creations/deletions */
663 	if (*p->blob != '\0' && p->old != NULL && p->new != NULL) {
664 		err = open_blob(&apath, &afile, p->blob, repo);
665 		/*
666 		 * ignore failures to open this blob, we might have
667 		 * parsed gibberish.
668 		 */
669 		if (err && !(err->code == GOT_ERR_ERRNO && errno == ENOENT) &&
670 		    err->code != GOT_ERR_NO_OBJ)
671 			return err;
672 		else if (err == NULL)
673 			do_merge = 1;
674 		err = NULL;
675 	}
676 
677 	if (asprintf(&oldpath, "%s/%s", got_worktree_get_root_path(worktree),
678 	    old) == -1) {
679 		err = got_error_from_errno("asprintf");
680 		goto done;
681 	}
682 
683 	if (asprintf(&newpath, "%s/%s", got_worktree_get_root_path(worktree),
684 	    new) == -1) {
685 		err = got_error_from_errno("asprintf");
686 		goto done;
687 	}
688 
689 	file_renamed = strcmp(oldpath, newpath);
690 
691 	if (asprintf(&template, "%s/got-patch",
692 	    got_worktree_get_root_path(worktree)) == -1) {
693 		err = got_error_from_errno(template);
694 		goto done;
695 	}
696 
697 	if (p->old != NULL && (oldfile = fopen(oldpath, "r")) == NULL) {
698 		err = got_error_from_errno2("open", oldpath);
699 		goto done;
700 	}
701 
702 	err = got_opentemp_named(&tmppath, &tmpfile, template);
703 	if (err)
704 		goto done;
705 	outpath = tmppath;
706 	outfd = fileno(tmpfile);
707 	err = patch_file(p, afile != NULL ? afile : oldfile, tmpfile, &mode);
708 	if (err)
709 		goto done;
710 
711 	if (do_merge) {
712 		const char *type, *id;
713 
714 		if (fseeko(afile, 0, SEEK_SET) == -1 ||
715 		    fseeko(oldfile, 0, SEEK_SET) == -1 ||
716 		    fseeko(tmpfile, 0, SEEK_SET) == -1) {
717 			err = got_error_from_errno("fseeko");
718 			goto done;
719 		}
720 
721 		if (asprintf(&oldlabel, "--- %s", p->old) == -1) {
722 			err = got_error_from_errno("asprintf");
723 			oldlabel = NULL;
724 			goto done;
725 		}
726 
727 		if (asprintf(&newlabel, "+++ %s", p->new) == -1) {
728 			err = got_error_from_errno("asprintf");
729 			newlabel = NULL;
730 			goto done;
731 		}
732 
733 		if (*p->cid != '\0') {
734 			type = "commit";
735 			id = p->cid;
736 		} else {
737 			type = "blob";
738 			id = p->blob;
739 		}
740 
741 		if (asprintf(&anclabel, "%s %s", type, id) == -1) {
742 			err = got_error_from_errno("asprintf");
743 			anclabel = NULL;
744 			goto done;
745 		}
746 
747 		err = got_opentemp_named(&mergepath, &mergefile, template);
748 		if (err)
749 			goto done;
750 		outpath = mergepath;
751 		outfd = fileno(mergefile);
752 
753 		err = got_merge_diff3(overlapcnt, outfd, tmpfile, afile,
754 		    oldfile, oldlabel, anclabel, newlabel,
755 		    GOT_DIFF_ALGORITHM_PATIENCE);
756 		if (err)
757 			goto done;
758 	}
759 
760 	if (nop)
761 		goto done;
762 
763 	if (p->old != NULL && p->new == NULL) {
764 		err = got_worktree_patch_schedule_rm(old, repo, worktree,
765 		    fileindex, patch_delete, pa);
766 		goto done;
767 	}
768 
769 	if (fchmod(outfd, mode) == -1) {
770 		err = got_error_from_errno2("chmod", tmppath);
771 		goto done;
772 	}
773 
774 	if (rename(outpath, newpath) == -1) {
775 		if (errno != ENOENT) {
776 			err = got_error_from_errno3("rename", outpath,
777 			    newpath);
778 			goto done;
779 		}
780 
781 		err = got_path_dirname(&parent, newpath);
782 		if (err != NULL)
783 			goto done;
784 		err = got_path_mkdir(parent);
785 		if (err != NULL)
786 			goto done;
787 		if (rename(outpath, newpath) == -1) {
788 			err = got_error_from_errno3("rename", outpath,
789 			    newpath);
790 			goto done;
791 		}
792 	}
793 
794 	if (file_renamed) {
795 		err = got_worktree_patch_schedule_rm(old, repo, worktree,
796 		    fileindex, patch_delete, pa);
797 		if (err == NULL)
798 			err = got_worktree_patch_schedule_add(new, repo,
799 			    worktree, fileindex, patch_add,
800 			    pa);
801 		if (err)
802 			unlink(newpath);
803 	} else if (p->old == NULL) {
804 		err = got_worktree_patch_schedule_add(new, repo, worktree,
805 		    fileindex, patch_add, pa);
806 		if (err)
807 			unlink(newpath);
808 	} else if (*overlapcnt != 0)
809 		err = report_progress(pa, old, new, GOT_STATUS_CONFLICT, NULL);
810 	else if (do_merge)
811 		err = report_progress(pa, old, new, GOT_STATUS_MERGE, NULL);
812 	else
813 		err = report_progress(pa, old, new, GOT_STATUS_MODIFY, NULL);
814 
815 done:
816 	free(parent);
817 	free(template);
818 
819 	if (tmppath != NULL)
820 		unlink(tmppath);
821 	if (tmpfile != NULL && fclose(tmpfile) == EOF && err == NULL)
822 		err = got_error_from_errno("fclose");
823 	free(tmppath);
824 
825 	free(oldpath);
826 	if (oldfile != NULL && fclose(oldfile) == EOF && err == NULL)
827 		err = got_error_from_errno("fclose");
828 
829 	if (apath != NULL)
830 		unlink(apath);
831 	if (afile != NULL && fclose(afile) == EOF && err == NULL)
832 		err = got_error_from_errno("fclose");
833 	free(apath);
834 
835 	if (mergepath != NULL)
836 		unlink(mergepath);
837 	if (mergefile != NULL && fclose(mergefile) == EOF && err == NULL)
838 		err = got_error_from_errno("fclose");
839 	free(mergepath);
840 
841 	free(newpath);
842 	free(oldlabel);
843 	free(newlabel);
844 	free(anclabel);
845 	return err;
846 }
847 
848 static void
849 reverse_patch(struct got_patch *p)
850 {
851 	struct got_patch_hunk *h;
852 	size_t i;
853 	int tmp;
854 
855 	STAILQ_FOREACH(h, &p->head, entries) {
856 		tmp = h->old_from;
857 		h->old_from = h->new_from;
858 		h->new_from = tmp;
859 
860 		tmp = h->old_lines;
861 		h->old_lines = h->new_lines;
862 		h->new_lines = tmp;
863 
864 		tmp = h->old_nonl;
865 		h->old_nonl = h->new_nonl;
866 		h->new_nonl = tmp;
867 
868 		for (i = 0; i < h->len; ++i) {
869 			if (*h->lines[i] == '+')
870 				*h->lines[i] = '-';
871 			else if (*h->lines[i] == '-')
872 				*h->lines[i] = '+';
873 		}
874 	}
875 }
876 
877 const struct got_error *
878 got_patch(int fd, struct got_worktree *worktree, struct got_repository *repo,
879     int nop, int strip, int reverse, got_patch_progress_cb progress_cb,
880     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
881 {
882 	const struct got_error *err = NULL, *complete_err = NULL;
883 	struct got_fileindex *fileindex = NULL;
884 	char *fileindex_path = NULL;
885 	char *oldpath, *newpath;
886 	struct imsgbuf *ibuf;
887 	int imsg_fds[2] = {-1, -1};
888 	int overlapcnt, done = 0, failed = 0;
889 	pid_t pid;
890 
891 	ibuf = calloc(1, sizeof(*ibuf));
892 	if (ibuf == NULL) {
893 		err = got_error_from_errno("calloc");
894 		goto done;
895 	}
896 
897 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
898 		err = got_error_from_errno("socketpair");
899 		goto done;
900 	}
901 
902 	pid = fork();
903 	if (pid == -1) {
904 		err = got_error_from_errno("fork");
905 		goto done;
906 	} else if (pid == 0) {
907 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_PATCH,
908 		    NULL);
909 		/* not reached */
910 	}
911 
912 	if (close(imsg_fds[1]) == -1) {
913 		err = got_error_from_errno("close");
914 		goto done;
915 	}
916 	imsg_fds[1] = -1;
917 	imsg_init(ibuf, imsg_fds[0]);
918 
919 	err = send_patch(ibuf, fd);
920 	fd = -1;
921 	if (err)
922 		goto done;
923 
924 	err = got_worktree_patch_prepare(&fileindex, &fileindex_path,
925 	    worktree);
926 	if (err)
927 		goto done;
928 
929 	while (!done && err == NULL) {
930 		struct got_patch p;
931 		struct patch_args pa;
932 
933 		pa.progress_cb = progress_cb;
934 		pa.progress_arg = progress_arg;
935 		pa.head = &p.head;
936 
937 		err = recv_patch(ibuf, &done, &p, strip);
938 		if (err || done)
939 			break;
940 
941 		if (reverse)
942 			reverse_patch(&p);
943 
944 		err = got_worktree_patch_check_path(p.old, p.new, &oldpath,
945 		    &newpath, worktree, repo, fileindex);
946 		if (err == NULL)
947 			err = apply_patch(&overlapcnt, worktree, repo,
948 			    fileindex, oldpath, newpath, &p, nop, &pa,
949 			    cancel_cb, cancel_arg);
950 		if (err != NULL) {
951 			failed = 1;
952 			/* recoverable errors */
953 			if (err->code == GOT_ERR_FILE_STATUS ||
954 			    (err->code == GOT_ERR_ERRNO && errno == ENOENT))
955 				err = report_progress(&pa, p.old, p.new,
956 				    GOT_STATUS_CANNOT_UPDATE, err);
957 			else if (err->code == GOT_ERR_HUNK_FAILED)
958 				err = report_progress(&pa, p.old, p.new,
959 				    GOT_STATUS_CANNOT_UPDATE, NULL);
960 		}
961 		if (overlapcnt != 0)
962 			failed = 1;
963 
964 		free(oldpath);
965 		free(newpath);
966 		patch_free(&p);
967 
968 		if (err)
969 			break;
970 	}
971 
972 done:
973 	if (fileindex != NULL)
974 		complete_err = got_worktree_patch_complete(fileindex,
975 		    fileindex_path);
976 	if (complete_err && err == NULL)
977 		err = complete_err;
978 	free(fileindex_path);
979 	if (fd != -1 && close(fd) == -1 && err == NULL)
980 		err = got_error_from_errno("close");
981 	if (ibuf != NULL)
982 		imsg_clear(ibuf);
983 	if (imsg_fds[0] != -1 && close(imsg_fds[0]) == -1 && err == NULL)
984 		err = got_error_from_errno("close");
985 	if (imsg_fds[1] != -1 && close(imsg_fds[1]) == -1 && err == NULL)
986 		err = got_error_from_errno("close");
987 	if (err == NULL && failed)
988 		err = got_error(GOT_ERR_PATCH_FAILED);
989 	return err;
990 }