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Date:: Sat Jul 27 14:42:04 2019 UTC
Message:: add conversion functions for fileindex/stat permission bits
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1 /*
2  * Copyright (c) 2018, 2019 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/tree.h>
19 #include <sys/stat.h>
20 
21 #include <errno.h>
22 #include <dirent.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <sha1.h>
27 #include <endian.h>
28 #include <limits.h>
29 #include <uuid.h>
30 
31 #include "got_error.h"
32 #include "got_object.h"
33 #include "got_path.h"
34 
35 #include "got_lib_fileindex.h"
36 #include "got_lib_worktree.h"
37 
38 /* got_fileindex_entry flags */
39 #define GOT_FILEIDX_F_PATH_LEN		0x00000fff
40 #define GOT_FILEIDX_F_STAGE		0x00003000
41 #define GOT_FILEIDX_F_EXTENDED		0x00004000
42 #define GOT_FILEIDX_F_ASSUME_VALID	0x00008000
43 #define GOT_FILEIDX_F_NOT_FLUSHED	0x00010000
44 #define GOT_FILEIDX_F_NO_BLOB		0x00020000
45 #define GOT_FILEIDX_F_NO_COMMIT		0x00040000
46 #define GOT_FILEIDX_F_NO_FILE_ON_DISK	0x00080000
47 
48 struct got_fileindex {
49 	struct got_fileindex_tree entries;
50 	int nentries;
51 #define GOT_FILEIDX_MAX_ENTRIES INT_MAX
52 };
53 
54 uint16_t
55 got_fileindex_perms_from_st(struct stat *sb)
56 {
57 	uint16_t perms = (sb->st_mode & (S_IRWXU | S_IRWXG | S_IRWXO));
58 	return (perms << GOT_FILEIDX_MODE_PERMS_SHIFT);
59 }
60 
61 mode_t
62 got_fileindex_perms_to_st(struct got_fileindex_entry *ie)
63 {
64 	mode_t perms = (ie->mode >> GOT_FILEIDX_MODE_PERMS_SHIFT);
65 	return (perms & (S_IRWXU | S_IRWXG | S_IRWXO));
66 }
67 
68 const struct got_error *
69 got_fileindex_entry_update(struct got_fileindex_entry *entry,
70     const char *ondisk_path, uint8_t *blob_sha1, uint8_t *commit_sha1,
71     int update_timestamps)
72 {
73 	struct stat sb;
74 
75 	if (lstat(ondisk_path, &sb) != 0) {
76 		if ((entry->flags & GOT_FILEIDX_F_NO_FILE_ON_DISK) == 0)
77 			return got_error_from_errno2("lstat", ondisk_path);
78 	} else {
79 		if (sb.st_mode & S_IFDIR)
80 			return got_error_set_errno(EISDIR, ondisk_path);
81 		entry->flags &= ~GOT_FILEIDX_F_NO_FILE_ON_DISK;
82 	}
83 
84 
85 	if ((entry->flags & GOT_FILEIDX_F_NO_FILE_ON_DISK) == 0) {
86 		if (update_timestamps) {
87 			entry->ctime_sec = sb.st_ctime;
88 			entry->ctime_nsec = sb.st_ctimensec;
89 			entry->mtime_sec = sb.st_mtime;
90 			entry->mtime_nsec = sb.st_mtimensec;
91 		}
92 		entry->uid = sb.st_uid;
93 		entry->gid = sb.st_gid;
94 		entry->size = (sb.st_size & 0xffffffff);
95 		if (sb.st_mode & S_IFLNK)
96 			entry->mode = GOT_FILEIDX_MODE_SYMLINK;
97 		else
98 			entry->mode = GOT_FILEIDX_MODE_REGULAR_FILE;
99 		entry->mode |= got_fileindex_perms_from_st(&sb);
100 	}
101 
102 	if (blob_sha1) {
103 		memcpy(entry->blob_sha1, blob_sha1, SHA1_DIGEST_LENGTH);
104 		entry->flags &= ~GOT_FILEIDX_F_NO_BLOB;
105 	} else
106 		entry->flags |= GOT_FILEIDX_F_NO_BLOB;
107 
108 	if (commit_sha1) {
109 		memcpy(entry->commit_sha1, commit_sha1, SHA1_DIGEST_LENGTH);
110 		entry->flags &= ~GOT_FILEIDX_F_NO_COMMIT;
111 	} else
112 		entry->flags |= GOT_FILEIDX_F_NO_COMMIT;
113 
114 	return NULL;
115 }
116 
117 void
118 got_fileindex_entry_mark_deleted_from_disk(struct got_fileindex_entry *entry)
119 {
120 	entry->flags |= GOT_FILEIDX_F_NO_FILE_ON_DISK;
121 }
122 
123 const struct got_error *
124 got_fileindex_entry_alloc(struct got_fileindex_entry **entry,
125     const char *ondisk_path, const char *relpath, uint8_t *blob_sha1,
126     uint8_t *commit_sha1)
127 {
128 	size_t len;
129 
130 	*entry = calloc(1, sizeof(**entry));
131 	if (*entry == NULL)
132 		return got_error_from_errno("calloc");
133 
134 	(*entry)->path = strdup(relpath);
135 	if ((*entry)->path == NULL) {
136 		const struct got_error *err = got_error_from_errno("strdup");
137 		free(*entry);
138 		*entry = NULL;
139 		return err;
140 	}
141 
142 	len = strlen(relpath);
143 	if (len > GOT_FILEIDX_F_PATH_LEN)
144 		len = GOT_FILEIDX_F_PATH_LEN;
145 	(*entry)->flags |= len;
146 
147 	return got_fileindex_entry_update(*entry, ondisk_path, blob_sha1,
148 	    commit_sha1, 1);
149 }
150 
151 void
152 got_fileindex_entry_free(struct got_fileindex_entry *entry)
153 {
154 	free(entry->path);
155 	free(entry);
156 }
157 
158 int
159 got_fileindex_entry_has_blob(struct got_fileindex_entry *ie)
160 {
161 	return (ie->flags & GOT_FILEIDX_F_NO_BLOB) == 0;
162 }
163 
164 int
165 got_fileindex_entry_has_commit(struct got_fileindex_entry *ie)
166 {
167 	return (ie->flags & GOT_FILEIDX_F_NO_COMMIT) == 0;
168 }
169 
170 int
171 got_fileindex_entry_has_file_on_disk(struct got_fileindex_entry *ie)
172 {
173 	return (ie->flags & GOT_FILEIDX_F_NO_FILE_ON_DISK) == 0;
174 }
175 
176 static const struct got_error *
177 add_entry(struct got_fileindex *fileindex, struct got_fileindex_entry *entry)
178 {
179 	if (fileindex->nentries >= GOT_FILEIDX_MAX_ENTRIES)
180 		return got_error(GOT_ERR_NO_SPACE);
181 
182 	RB_INSERT(got_fileindex_tree, &fileindex->entries, entry);
183 	fileindex->nentries++;
184 	return NULL;
185 }
186 
187 const struct got_error *
188 got_fileindex_entry_add(struct got_fileindex *fileindex,
189     struct got_fileindex_entry *entry)
190 {
191 	/* Flag this entry until it gets written out to disk. */
192 	entry->flags |= GOT_FILEIDX_F_NOT_FLUSHED;
193 
194 	return add_entry(fileindex, entry);
195 }
196 
197 void
198 got_fileindex_entry_remove(struct got_fileindex *fileindex,
199     struct got_fileindex_entry *entry)
200 {
201 	RB_REMOVE(got_fileindex_tree, &fileindex->entries, entry);
202 	fileindex->nentries--;
203 }
204 
205 struct got_fileindex_entry *
206 got_fileindex_entry_get(struct got_fileindex *fileindex, const char *path)
207 {
208 	struct got_fileindex_entry key;
209 	memset(&key, 0, sizeof(key));
210 	key.path = (char *)path;
211 	return RB_FIND(got_fileindex_tree, &fileindex->entries, &key);
212 }
213 
214 const struct got_error *
215 got_fileindex_for_each_entry_safe(struct got_fileindex *fileindex,
216     got_fileindex_cb cb, void *cb_arg)
217 {
218 	const struct got_error *err;
219 	struct got_fileindex_entry *entry, *tmp;
220 
221 	RB_FOREACH_SAFE(entry, got_fileindex_tree, &fileindex->entries, tmp) {
222 		err = (*cb)(cb_arg, entry);
223 		if (err)
224 			return err;
225 	}
226 	return NULL;
227 }
228 
229 struct got_fileindex *
230 got_fileindex_alloc(void)
231 {
232 	struct got_fileindex *fileindex;
233 
234 	fileindex = calloc(1, sizeof(*fileindex));
235 	if (fileindex == NULL)
236 		return NULL;
237 
238 	RB_INIT(&fileindex->entries);
239 	return fileindex;
240 }
241 
242 void
243 got_fileindex_free(struct got_fileindex *fileindex)
244 {
245 	struct got_fileindex_entry *entry;
246 
247 	while ((entry = RB_MIN(got_fileindex_tree, &fileindex->entries))) {
248 		RB_REMOVE(got_fileindex_tree, &fileindex->entries, entry);
249 		got_fileindex_entry_free(entry);
250 	}
251 	free(fileindex);
252 }
253 
254 static const struct got_error *
255 write_fileindex_val64(SHA1_CTX *ctx, uint64_t val, FILE *outfile)
256 {
257 	size_t n;
258 
259 	val = htobe64(val);
260 	SHA1Update(ctx, (uint8_t *)&val, sizeof(val));
261 	n = fwrite(&val, 1, sizeof(val), outfile);
262 	if (n != sizeof(val))
263 		return got_ferror(outfile, GOT_ERR_IO);
264 	return NULL;
265 }
266 
267 static const struct got_error *
268 write_fileindex_val32(SHA1_CTX *ctx, uint32_t val, FILE *outfile)
269 {
270 	size_t n;
271 
272 	val = htobe32(val);
273 	SHA1Update(ctx, (uint8_t *)&val, sizeof(val));
274 	n = fwrite(&val, 1, sizeof(val), outfile);
275 	if (n != sizeof(val))
276 		return got_ferror(outfile, GOT_ERR_IO);
277 	return NULL;
278 }
279 
280 static const struct got_error *
281 write_fileindex_val16(SHA1_CTX *ctx, uint16_t val, FILE *outfile)
282 {
283 	size_t n;
284 
285 	val = htobe16(val);
286 	SHA1Update(ctx, (uint8_t *)&val, sizeof(val));
287 	n = fwrite(&val, 1, sizeof(val), outfile);
288 	if (n != sizeof(val))
289 		return got_ferror(outfile, GOT_ERR_IO);
290 	return NULL;
291 }
292 
293 static const struct got_error *
294 write_fileindex_path(SHA1_CTX *ctx, const char *path, FILE *outfile)
295 {
296 	size_t n, len, pad = 0;
297 	static const uint8_t zero[8] = { 0 };
298 
299 	len = strlen(path);
300 	while ((len + pad) % 8 != 0)
301 		pad++;
302 	if (pad == 0)
303 		pad = 8; /* NUL-terminate */
304 
305 	SHA1Update(ctx, path, len);
306 	n = fwrite(path, 1, len, outfile);
307 	if (n != len)
308 		return got_ferror(outfile, GOT_ERR_IO);
309 	SHA1Update(ctx, zero, pad);
310 	n = fwrite(zero, 1, pad, outfile);
311 	if (n != pad)
312 		return got_ferror(outfile, GOT_ERR_IO);
313 	return NULL;
314 }
315 
316 static const struct got_error *
317 write_fileindex_entry(SHA1_CTX *ctx, struct got_fileindex_entry *entry,
318     FILE *outfile)
319 {
320 	const struct got_error *err;
321 	size_t n;
322 
323 	err = write_fileindex_val64(ctx, entry->ctime_sec, outfile);
324 	if (err)
325 		return err;
326 	err = write_fileindex_val64(ctx, entry->ctime_nsec, outfile);
327 	if (err)
328 		return err;
329 	err = write_fileindex_val64(ctx, entry->mtime_sec, outfile);
330 	if (err)
331 		return err;
332 	err = write_fileindex_val64(ctx, entry->mtime_nsec, outfile);
333 	if (err)
334 		return err;
335 
336 	err = write_fileindex_val32(ctx, entry->uid, outfile);
337 	if (err)
338 		return err;
339 	err = write_fileindex_val32(ctx, entry->gid, outfile);
340 	if (err)
341 		return err;
342 	err = write_fileindex_val32(ctx, entry->size, outfile);
343 	if (err)
344 		return err;
345 
346 	err = write_fileindex_val16(ctx, entry->mode, outfile);
347 	if (err)
348 		return err;
349 
350 	SHA1Update(ctx, entry->blob_sha1, SHA1_DIGEST_LENGTH);
351 	n = fwrite(entry->blob_sha1, 1, SHA1_DIGEST_LENGTH, outfile);
352 	if (n != SHA1_DIGEST_LENGTH)
353 		return got_ferror(outfile, GOT_ERR_IO);
354 
355 	SHA1Update(ctx, entry->commit_sha1, SHA1_DIGEST_LENGTH);
356 	n = fwrite(entry->commit_sha1, 1, SHA1_DIGEST_LENGTH, outfile);
357 	if (n != SHA1_DIGEST_LENGTH)
358 		return got_ferror(outfile, GOT_ERR_IO);
359 
360 	err = write_fileindex_val32(ctx, entry->flags, outfile);
361 	if (err)
362 		return err;
363 
364 	err = write_fileindex_path(ctx, entry->path, outfile);
365 	return err;
366 }
367 
368 const struct got_error *
369 got_fileindex_write(struct got_fileindex *fileindex, FILE *outfile)
370 {
371 	const struct got_error *err = NULL;
372 	struct got_fileindex_hdr hdr;
373 	SHA1_CTX ctx;
374 	uint8_t sha1[SHA1_DIGEST_LENGTH];
375 	size_t n;
376 	struct got_fileindex_entry *entry;
377 
378 	SHA1Init(&ctx);
379 
380 	hdr.signature = htobe32(GOT_FILE_INDEX_SIGNATURE);
381 	hdr.version = htobe32(GOT_FILE_INDEX_VERSION);
382 	hdr.nentries = htobe32(fileindex->nentries);
383 
384 	SHA1Update(&ctx, (uint8_t *)&hdr.signature, sizeof(hdr.signature));
385 	SHA1Update(&ctx, (uint8_t *)&hdr.version, sizeof(hdr.version));
386 	SHA1Update(&ctx, (uint8_t *)&hdr.nentries, sizeof(hdr.nentries));
387 	n = fwrite(&hdr.signature, 1, sizeof(hdr.signature), outfile);
388 	if (n != sizeof(hdr.signature))
389 		return got_ferror(outfile, GOT_ERR_IO);
390 	n = fwrite(&hdr.version, 1, sizeof(hdr.version), outfile);
391 	if (n != sizeof(hdr.version))
392 		return got_ferror(outfile, GOT_ERR_IO);
393 	n = fwrite(&hdr.nentries, 1, sizeof(hdr.nentries), outfile);
394 	if (n != sizeof(hdr.nentries))
395 		return got_ferror(outfile, GOT_ERR_IO);
396 
397 	RB_FOREACH(entry, got_fileindex_tree, &fileindex->entries) {
398 		entry->flags &= ~GOT_FILEIDX_F_NOT_FLUSHED;
399 		err = write_fileindex_entry(&ctx, entry, outfile);
400 		if (err)
401 			return err;
402 	}
403 
404 	SHA1Final(sha1, &ctx);
405 	n = fwrite(sha1, 1, sizeof(sha1), outfile);
406 	if (n != sizeof(sha1))
407 		return got_ferror(outfile, GOT_ERR_IO);
408 
409 	if (fflush(outfile) != 0)
410 		return got_error_from_errno("fflush");
411 
412 	return NULL;
413 }
414 
415 static const struct got_error *
416 read_fileindex_val64(uint64_t *val, SHA1_CTX *ctx, FILE *infile)
417 {
418 	size_t n;
419 
420 	n = fread(val, 1, sizeof(*val), infile);
421 	if (n != sizeof(*val))
422 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
423 	SHA1Update(ctx, (uint8_t *)val, sizeof(*val));
424 	*val = be64toh(*val);
425 	return NULL;
426 }
427 
428 static const struct got_error *
429 read_fileindex_val32(uint32_t *val, SHA1_CTX *ctx, FILE *infile)
430 {
431 	size_t n;
432 
433 	n = fread(val, 1, sizeof(*val), infile);
434 	if (n != sizeof(*val))
435 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
436 	SHA1Update(ctx, (uint8_t *)val, sizeof(*val));
437 	*val = be32toh(*val);
438 	return NULL;
439 }
440 
441 static const struct got_error *
442 read_fileindex_val16(uint16_t *val, SHA1_CTX *ctx, FILE *infile)
443 {
444 	size_t n;
445 
446 	n = fread(val, 1, sizeof(*val), infile);
447 	if (n != sizeof(*val))
448 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
449 	SHA1Update(ctx, (uint8_t *)val, sizeof(*val));
450 	*val = be16toh(*val);
451 	return NULL;
452 }
453 
454 static const struct got_error *
455 read_fileindex_path(char **path, SHA1_CTX *ctx, FILE *infile)
456 {
457 	const struct got_error *err = NULL;
458 	uint8_t buf[8];
459 	size_t n, len = 0, totlen = sizeof(buf);
460 
461 	*path = malloc(totlen);
462 	if (*path == NULL)
463 		return got_error_from_errno("malloc");
464 
465 	do {
466 		n = fread(buf, 1, sizeof(buf), infile);
467 		if (n != sizeof(buf))
468 			return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
469 		if (len + sizeof(buf) > totlen) {
470 			char *p = reallocarray(*path, totlen + sizeof(buf), 1);
471 			if (p == NULL) {
472 				err = got_error_from_errno("reallocarray");
473 				break;
474 			}
475 			totlen += sizeof(buf);
476 			*path = p;
477 		}
478 		SHA1Update(ctx, buf, sizeof(buf));
479 		memcpy(*path + len, buf, sizeof(buf));
480 		len += sizeof(buf);
481 	} while (memchr(buf, '\0', sizeof(buf)) == NULL);
482 
483 	if (err) {
484 		free(*path);
485 		*path = NULL;
486 	}
487 	return err;
488 }
489 
490 static const struct got_error *
491 read_fileindex_entry(struct got_fileindex_entry **entryp, SHA1_CTX *ctx,
492     FILE *infile)
493 {
494 	const struct got_error *err;
495 	struct got_fileindex_entry *entry;
496 	size_t n;
497 
498 	*entryp = NULL;
499 
500 	entry = calloc(1, sizeof(*entry));
501 	if (entry == NULL)
502 		return got_error_from_errno("calloc");
503 
504 	err = read_fileindex_val64(&entry->ctime_sec, ctx, infile);
505 	if (err)
506 		goto done;
507 	err = read_fileindex_val64(&entry->ctime_nsec, ctx, infile);
508 	if (err)
509 		goto done;
510 	err = read_fileindex_val64(&entry->mtime_sec, ctx, infile);
511 	if (err)
512 		goto done;
513 	err = read_fileindex_val64(&entry->mtime_nsec, ctx, infile);
514 	if (err)
515 		goto done;
516 
517 	err = read_fileindex_val32(&entry->uid, ctx, infile);
518 	if (err)
519 		goto done;
520 	err = read_fileindex_val32(&entry->gid, ctx, infile);
521 	if (err)
522 		goto done;
523 	err = read_fileindex_val32(&entry->size, ctx, infile);
524 	if (err)
525 		goto done;
526 
527 	err = read_fileindex_val16(&entry->mode, ctx, infile);
528 	if (err)
529 		goto done;
530 
531 	n = fread(entry->blob_sha1, 1, SHA1_DIGEST_LENGTH, infile);
532 	if (n != SHA1_DIGEST_LENGTH) {
533 		err = got_ferror(infile, GOT_ERR_FILEIDX_BAD);
534 		goto done;
535 	}
536 	SHA1Update(ctx, entry->blob_sha1, SHA1_DIGEST_LENGTH);
537 
538 	n = fread(entry->commit_sha1, 1, SHA1_DIGEST_LENGTH, infile);
539 	if (n != SHA1_DIGEST_LENGTH) {
540 		err = got_ferror(infile, GOT_ERR_FILEIDX_BAD);
541 		goto done;
542 	}
543 	SHA1Update(ctx, entry->commit_sha1, SHA1_DIGEST_LENGTH);
544 
545 	err = read_fileindex_val32(&entry->flags, ctx, infile);
546 	if (err)
547 		goto done;
548 
549 	err = read_fileindex_path(&entry->path, ctx, infile);
550 done:
551 	if (err)
552 		free(entry);
553 	else
554 		*entryp = entry;
555 	return err;
556 }
557 
558 const struct got_error *
559 got_fileindex_read(struct got_fileindex *fileindex, FILE *infile)
560 {
561 	const struct got_error *err = NULL;
562 	struct got_fileindex_hdr hdr;
563 	SHA1_CTX ctx;
564 	struct got_fileindex_entry *entry;
565 	uint8_t sha1_expected[SHA1_DIGEST_LENGTH];
566 	uint8_t sha1[SHA1_DIGEST_LENGTH];
567 	size_t n;
568 	int i;
569 
570 	SHA1Init(&ctx);
571 
572 	n = fread(&hdr.signature, 1, sizeof(hdr.signature), infile);
573 	if (n != sizeof(hdr.signature)) {
574 		if (n == 0) /* EOF */
575 			return NULL;
576 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
577 	}
578 	n = fread(&hdr.version, 1, sizeof(hdr.version), infile);
579 	if (n != sizeof(hdr.version)) {
580 		if (n == 0) /* EOF */
581 			return NULL;
582 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
583 	}
584 	n = fread(&hdr.nentries, 1, sizeof(hdr.nentries), infile);
585 	if (n != sizeof(hdr.nentries)) {
586 		if (n == 0) /* EOF */
587 			return NULL;
588 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
589 	}
590 
591 	SHA1Update(&ctx, (uint8_t *)&hdr.signature, sizeof(hdr.signature));
592 	SHA1Update(&ctx, (uint8_t *)&hdr.version, sizeof(hdr.version));
593 	SHA1Update(&ctx, (uint8_t *)&hdr.nentries, sizeof(hdr.nentries));
594 
595 	hdr.signature = be32toh(hdr.signature);
596 	hdr.version = be32toh(hdr.version);
597 	hdr.nentries = be32toh(hdr.nentries);
598 
599 	if (hdr.signature != GOT_FILE_INDEX_SIGNATURE)
600 		return got_error(GOT_ERR_FILEIDX_SIG);
601 	if (hdr.version != GOT_FILE_INDEX_VERSION)
602 		return got_error(GOT_ERR_FILEIDX_VER);
603 
604 	for (i = 0; i < hdr.nentries; i++) {
605 		err = read_fileindex_entry(&entry, &ctx, infile);
606 		if (err)
607 			return err;
608 		err = add_entry(fileindex, entry);
609 		if (err)
610 			return err;
611 	}
612 
613 	n = fread(sha1_expected, 1, sizeof(sha1_expected), infile);
614 	if (n != sizeof(sha1_expected))
615 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
616 	SHA1Final(sha1, &ctx);
617 	if (memcmp(sha1, sha1_expected, SHA1_DIGEST_LENGTH) != 0)
618 		return got_error(GOT_ERR_FILEIDX_CSUM);
619 
620 	return NULL;
621 }
622 
623 static struct got_fileindex_entry *
624 walk_fileindex(struct got_fileindex *fileindex, struct got_fileindex_entry *ie)
625 {
626 	struct got_fileindex_entry *next;
627 
628 	next = RB_NEXT(got_fileindex_tree, &fileindex->entries, ie);
629 
630 	/* Skip entries which were newly added by diff callbacks. */
631 	while (next && (next->flags & GOT_FILEIDX_F_NOT_FLUSHED))
632 		next = RB_NEXT(got_fileindex_tree, &fileindex->entries, next);
633 
634 	return next;
635 }
636 
637 static const struct got_error *
638 diff_fileindex_tree(struct got_fileindex *, struct got_fileindex_entry **,
639     const struct got_tree_entries *, const char *, const char *,
640     struct got_repository *, struct got_fileindex_diff_tree_cb *, void *);
641 
642 static const struct got_error *
643 walk_tree(struct got_tree_entry **next, struct got_fileindex *fileindex,
644     struct got_fileindex_entry **ie, struct got_tree_entry *te,
645     const char *path, const char *entry_name, struct got_repository *repo,
646     struct got_fileindex_diff_tree_cb *cb, void *cb_arg)
647 {
648 	const struct got_error *err = NULL;
649 
650 	if (S_ISDIR(te->mode)) {
651 		char *subpath;
652 		struct got_tree_object *subtree;
653 
654 		if (asprintf(&subpath, "%s%s%s", path,
655 		    path[0] == '\0' ? "" : "/", te->name) == -1)
656 			return got_error_from_errno("asprintf");
657 
658 		err = got_object_open_as_tree(&subtree, repo, te->id);
659 		if (err) {
660 			free(subpath);
661 			return err;
662 		}
663 
664 		err = diff_fileindex_tree(fileindex, ie,
665 		    got_object_tree_get_entries(subtree), subpath, entry_name,
666 		    repo, cb, cb_arg);
667 		free(subpath);
668 		got_object_tree_close(subtree);
669 		if (err)
670 			return err;
671 	}
672 
673 	*next = SIMPLEQ_NEXT(te, entry);
674 	return NULL;
675 }
676 
677 static const struct got_error *
678 diff_fileindex_tree(struct got_fileindex *fileindex,
679     struct got_fileindex_entry **ie, const struct got_tree_entries *entries,
680     const char *path, const char *entry_name, struct got_repository *repo,
681     struct got_fileindex_diff_tree_cb *cb, void *cb_arg)
682 {
683 	const struct got_error *err = NULL;
684 	struct got_tree_entry *te = NULL;
685 	size_t path_len = strlen(path);
686 	struct got_fileindex_entry *next;
687 
688 	te = SIMPLEQ_FIRST(&entries->head);
689 	while ((*ie && got_path_is_child((*ie)->path, path, path_len)) || te) {
690 		if (te && *ie) {
691 			char *te_path;
692 			int cmp;
693 			if (asprintf(&te_path, "%s/%s", path, te->name) == -1) {
694 				err = got_error_from_errno("asprintf");
695 				break;
696 			}
697 			cmp = got_path_cmp((*ie)->path, te_path);
698 			free(te_path);
699 			if (cmp == 0) {
700 				if (got_path_is_child((*ie)->path, path,
701 				    path_len) && (entry_name == NULL ||
702 				    strcmp(te->name, entry_name) == 0)) {
703 					err = cb->diff_old_new(cb_arg, *ie, te,
704 					    path);
705 					if (err || entry_name)
706 						break;
707 				}
708 				*ie = walk_fileindex(fileindex, *ie);
709 				err = walk_tree(&te, fileindex, ie, te,
710 				    path, entry_name, repo, cb, cb_arg);
711 			} else if (cmp < 0) {
712 				next = walk_fileindex(fileindex, *ie);
713 				if (got_path_is_child((*ie)->path, path,
714 				    path_len) && (entry_name == NULL ||
715 				    strcmp(te->name, entry_name) == 0)) {
716 					err = cb->diff_old(cb_arg, *ie, path);
717 					if (err || entry_name)
718 						break;
719 				}
720 				*ie = next;
721 			} else {
722 				if ((entry_name == NULL ||
723 				    strcmp(te->name, entry_name) == 0)) {
724 					err = cb->diff_new(cb_arg, te, path);
725 					if (err || entry_name)
726 						break;
727 				}
728 				err = walk_tree(&te, fileindex, ie, te,
729 				    path, entry_name, repo, cb, cb_arg);
730 			}
731 			if (err)
732 				break;
733 		} else if (*ie) {
734 			next = walk_fileindex(fileindex, *ie);
735 			if (got_path_is_child((*ie)->path, path, path_len) &&
736 			    (entry_name == NULL ||
737 			    strcmp(te->name, entry_name) == 0)) {
738 				err = cb->diff_old(cb_arg, *ie, path);
739 				if (err || entry_name)
740 					break;
741 			}
742 			*ie = next;
743 		} else if (te) {
744 			if (entry_name == NULL ||
745 			    strcmp(te->name, entry_name) == 0) {
746 				err = cb->diff_new(cb_arg, te, path);
747 				if (err || entry_name)
748 					break;
749 			}
750 			err = walk_tree(&te, fileindex, ie, te, path,
751 			    entry_name, repo, cb, cb_arg);
752 			if (err)
753 				break;
754 		}
755 	}
756 
757 	return err;
758 }
759 
760 const struct got_error *
761 got_fileindex_diff_tree(struct got_fileindex *fileindex,
762     struct got_tree_object *tree, const char *path, const char *entry_name,
763     struct got_repository *repo,
764     struct got_fileindex_diff_tree_cb *cb, void *cb_arg)
765 {
766 	struct got_fileindex_entry *ie;
767 	ie = RB_MIN(got_fileindex_tree, &fileindex->entries);
768 	while (ie && !got_path_is_child(ie->path, path, strlen(path)))
769 		ie = walk_fileindex(fileindex, ie);
770 	return diff_fileindex_tree(fileindex, &ie,
771 	    got_object_tree_get_entries(tree), path, entry_name, repo,
772 	    cb, cb_arg);
773 }
774 
775 static const struct got_error *
776 diff_fileindex_dir(struct got_fileindex *, struct got_fileindex_entry **,
777     struct got_pathlist_head *, const char *, const char *,
778     struct got_repository *, struct got_fileindex_diff_dir_cb *, void *);
779 
780 static const struct got_error *
781 read_dirlist(struct got_pathlist_head *dirlist, DIR *dir, const char *path)
782 {
783 	const struct got_error *err = NULL;
784 	struct got_pathlist_entry *new = NULL;
785 	struct dirent *dep = NULL;
786 	struct dirent *de = NULL;
787 
788 	for (;;) {
789 		de = malloc(sizeof(struct dirent) + NAME_MAX + 1);
790 		if (de == NULL) {
791 			err = got_error_from_errno("malloc");
792 			break;
793 		}
794 
795 		if (readdir_r(dir, de, &dep) != 0) {
796 			err = got_error_from_errno("readdir_r");
797 			free(de);
798 			break;
799 		}
800 		if (dep == NULL) {
801 			free(de);
802 			break;
803 		}
804 
805 		if (strcmp(de->d_name, ".") == 0 ||
806 		    strcmp(de->d_name, "..") == 0 ||
807 		    (path[0] == '\0' &&
808 		    strcmp(de->d_name, GOT_WORKTREE_GOT_DIR) == 0)) {
809 			free(de);
810 			continue;
811 		}
812 
813 		err = got_pathlist_insert(&new, dirlist, de->d_name, de);
814 		if (err) {
815 			free(de);
816 			break;
817 		}
818 		if (new == NULL) {
819 			err = got_error(GOT_ERR_DIR_DUP_ENTRY);
820 			free(de);
821 			break;
822 		}
823 	}
824 
825 	return err;
826 }
827 
828 void
829 free_dirlist(struct got_pathlist_head *dirlist)
830 {
831 	struct got_pathlist_entry *dle;
832 
833 	TAILQ_FOREACH(dle, dirlist, entry)
834 		free(dle->data);
835 	got_pathlist_free(dirlist);
836 }
837 
838 static const struct got_error *
839 walk_dir(struct got_pathlist_entry **next, struct got_fileindex *fileindex,
840     struct got_fileindex_entry **ie, struct got_pathlist_entry *dle,
841     const char *path, const char *rootpath, struct got_repository *repo,
842     struct got_fileindex_diff_dir_cb *cb, void *cb_arg)
843 {
844 	const struct got_error *err = NULL;
845 	struct dirent *de = dle->data;
846 
847 	*next = NULL;
848 
849 	if (de->d_type == DT_DIR) {
850 		char *subpath;
851 		char *subdirpath;
852 		DIR *subdir;
853 		struct got_pathlist_head subdirlist;
854 
855 		TAILQ_INIT(&subdirlist);
856 
857 		if (asprintf(&subpath, "%s%s%s", path,
858 		    path[0] == '\0' ? "" : "/", de->d_name) == -1)
859 			return got_error_from_errno("asprintf");
860 
861 		if (asprintf(&subdirpath, "%s/%s", rootpath, subpath) == -1) {
862 			free(subpath);
863 			return got_error_from_errno("asprintf");
864 		}
865 
866 		subdir = opendir(subdirpath);
867 		if (subdir == NULL) {
868 			free(subpath);
869 			free(subdirpath);
870 			return got_error_from_errno2("opendir", subdirpath);
871 		}
872 
873 		err = read_dirlist(&subdirlist, subdir, subdirpath);
874 		if (err) {
875 			free(subpath);
876 			free(subdirpath);
877 			closedir(subdir);
878 			return err;
879 		}
880 		err = diff_fileindex_dir(fileindex, ie, &subdirlist, rootpath,
881 		    subpath, repo, cb, cb_arg);
882 		free(subpath);
883 		free(subdirpath);
884 		closedir(subdir);
885 		free_dirlist(&subdirlist);
886 		if (err)
887 			return err;
888 	}
889 
890 	*next = TAILQ_NEXT(dle, entry);
891 	return NULL;
892 }
893 
894 static const struct got_error *
895 diff_fileindex_dir(struct got_fileindex *fileindex,
896     struct got_fileindex_entry **ie, struct got_pathlist_head *dirlist,
897     const char *rootpath, const char *path, struct got_repository *repo,
898     struct got_fileindex_diff_dir_cb *cb, void *cb_arg)
899 {
900 	const struct got_error *err = NULL;
901 	struct dirent *de = NULL;
902 	size_t path_len = strlen(path);
903 	struct got_pathlist_entry *dle;
904 
905 	dle = TAILQ_FIRST(dirlist);
906 	while ((*ie && got_path_is_child((*ie)->path, path, path_len)) || dle) {
907 		if (dle && *ie) {
908 			char *de_path;
909 			int cmp;
910 			de = dle->data;
911 			if (asprintf(&de_path, "%s/%s", path,
912 			    de->d_name) == -1) {
913 				err = got_error_from_errno("asprintf");
914 				break;
915 			}
916 			cmp = got_path_cmp((*ie)->path, de_path);
917 			free(de_path);
918 			if (cmp == 0) {
919 				err = cb->diff_old_new(cb_arg, *ie, de, path);
920 				if (err)
921 					break;
922 				*ie = walk_fileindex(fileindex, *ie);
923 				err = walk_dir(&dle, fileindex, ie, dle, path,
924 				    rootpath, repo, cb, cb_arg);
925 			} else if (cmp < 0 ) {
926 				err = cb->diff_old(cb_arg, *ie, path);
927 				if (err)
928 					break;
929 				*ie = walk_fileindex(fileindex, *ie);
930 			} else {
931 				err = cb->diff_new(cb_arg, de, path);
932 				if (err)
933 					break;
934 				err = walk_dir(&dle, fileindex, ie, dle, path,
935 				    rootpath, repo, cb, cb_arg);
936 			}
937 			if (err)
938 				break;
939 		} else if (*ie) {
940 			err = cb->diff_old(cb_arg, *ie, path);
941 			if (err)
942 				break;
943 			*ie = walk_fileindex(fileindex, *ie);
944 		} else if (dle) {
945 			de = dle->data;
946 			err = cb->diff_new(cb_arg, de, path);
947 			if (err)
948 				break;
949 			err = walk_dir(&dle, fileindex, ie, dle, path,
950 			    rootpath, repo, cb, cb_arg);
951 			if (err)
952 				break;
953 		}
954 	}
955 
956 	return err;
957 }
958 
959 const struct got_error *
960 got_fileindex_diff_dir(struct got_fileindex *fileindex, DIR *rootdir,
961     const char *rootpath, const char *path, struct got_repository *repo,
962     struct got_fileindex_diff_dir_cb *cb, void *cb_arg)
963 {
964 	const struct got_error *err;
965 	struct got_fileindex_entry *ie;
966 	struct got_pathlist_head dirlist;
967 
968 	TAILQ_INIT(&dirlist);
969 	err = read_dirlist(&dirlist, rootdir, path);
970 	if (err)
971 		return err;
972 	ie = RB_MIN(got_fileindex_tree, &fileindex->entries);
973 	while (ie && !got_path_is_child(ie->path, path, strlen(path)))
974 		ie = walk_fileindex(fileindex, ie);
975 	err = diff_fileindex_dir(fileindex, &ie, &dirlist, rootpath, path,
976 	    repo, cb, cb_arg);
977 	free_dirlist(&dirlist);
978 	return err;
979 }
980 
981 RB_GENERATE(got_fileindex_tree, got_fileindex_entry, entry, got_fileindex_cmp);