Gotweb

Blob

Date:: Sat Aug 3 14:40:04 2019 UTC
Message:: add staged blob SHA1 to on-disk file index; bump file index version
Actions:: History | Blame | Raw File
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		0x0000f000
41 #define GOT_FILEIDX_F_STAGE_SHIFT	24
42 #define GOT_FILEIDX_F_NOT_FLUSHED	0x00010000
43 #define GOT_FILEIDX_F_NO_BLOB		0x00020000
44 #define GOT_FILEIDX_F_NO_COMMIT		0x00040000
45 #define GOT_FILEIDX_F_NO_FILE_ON_DISK	0x00080000
46 
47 struct got_fileindex {
48 	struct got_fileindex_tree entries;
49 	int nentries;
50 #define GOT_FILEIDX_MAX_ENTRIES INT_MAX
51 };
52 
53 uint16_t
54 got_fileindex_perms_from_st(struct stat *sb)
55 {
56 	uint16_t perms = (sb->st_mode & (S_IRWXU | S_IRWXG | S_IRWXO));
57 	return (perms << GOT_FILEIDX_MODE_PERMS_SHIFT);
58 }
59 
60 mode_t
61 got_fileindex_perms_to_st(struct got_fileindex_entry *ie)
62 {
63 	mode_t perms = (ie->mode >> GOT_FILEIDX_MODE_PERMS_SHIFT);
64 	return (perms & (S_IRWXU | S_IRWXG | S_IRWXO));
65 }
66 
67 const struct got_error *
68 got_fileindex_entry_update(struct got_fileindex_entry *ie,
69     const char *ondisk_path, uint8_t *blob_sha1, uint8_t *commit_sha1,
70     int update_timestamps)
71 {
72 	struct stat sb;
73 
74 	if (lstat(ondisk_path, &sb) != 0) {
75 		if ((ie->flags & GOT_FILEIDX_F_NO_FILE_ON_DISK) == 0)
76 			return got_error_from_errno2("lstat", ondisk_path);
77 	} else {
78 		if (sb.st_mode & S_IFDIR)
79 			return got_error_set_errno(EISDIR, ondisk_path);
80 		ie->flags &= ~GOT_FILEIDX_F_NO_FILE_ON_DISK;
81 	}
82 
83 
84 	if ((ie->flags & GOT_FILEIDX_F_NO_FILE_ON_DISK) == 0) {
85 		if (update_timestamps) {
86 			ie->ctime_sec = sb.st_ctime;
87 			ie->ctime_nsec = sb.st_ctimensec;
88 			ie->mtime_sec = sb.st_mtime;
89 			ie->mtime_nsec = sb.st_mtimensec;
90 		}
91 		ie->uid = sb.st_uid;
92 		ie->gid = sb.st_gid;
93 		ie->size = (sb.st_size & 0xffffffff);
94 		if (sb.st_mode & S_IFLNK)
95 			ie->mode = GOT_FILEIDX_MODE_SYMLINK;
96 		else
97 			ie->mode = GOT_FILEIDX_MODE_REGULAR_FILE;
98 		ie->mode |= got_fileindex_perms_from_st(&sb);
99 	}
100 
101 	if (blob_sha1) {
102 		memcpy(ie->blob_sha1, blob_sha1, SHA1_DIGEST_LENGTH);
103 		ie->flags &= ~GOT_FILEIDX_F_NO_BLOB;
104 	} else
105 		ie->flags |= GOT_FILEIDX_F_NO_BLOB;
106 
107 	if (commit_sha1) {
108 		memcpy(ie->commit_sha1, commit_sha1, SHA1_DIGEST_LENGTH);
109 		ie->flags &= ~GOT_FILEIDX_F_NO_COMMIT;
110 	} else
111 		ie->flags |= GOT_FILEIDX_F_NO_COMMIT;
112 
113 	return NULL;
114 }
115 
116 void
117 got_fileindex_entry_mark_deleted_from_disk(struct got_fileindex_entry *ie)
118 {
119 	ie->flags |= GOT_FILEIDX_F_NO_FILE_ON_DISK;
120 }
121 
122 const struct got_error *
123 got_fileindex_entry_alloc(struct got_fileindex_entry **ie,
124     const char *ondisk_path, const char *relpath, uint8_t *blob_sha1,
125     uint8_t *commit_sha1)
126 {
127 	size_t len;
128 
129 	*ie = calloc(1, sizeof(**ie));
130 	if (*ie == NULL)
131 		return got_error_from_errno("calloc");
132 
133 	(*ie)->path = strdup(relpath);
134 	if ((*ie)->path == NULL) {
135 		const struct got_error *err = got_error_from_errno("strdup");
136 		free(*ie);
137 		*ie = NULL;
138 		return err;
139 	}
140 
141 	len = strlen(relpath);
142 	if (len > GOT_FILEIDX_F_PATH_LEN)
143 		len = GOT_FILEIDX_F_PATH_LEN;
144 	(*ie)->flags |= len;
145 
146 	return got_fileindex_entry_update(*ie, ondisk_path, blob_sha1,
147 	    commit_sha1, 1);
148 }
149 
150 void
151 got_fileindex_entry_free(struct got_fileindex_entry *ie)
152 {
153 	free(ie->path);
154 	free(ie);
155 }
156 
157 size_t
158 got_fileindex_entry_path_len(const struct got_fileindex_entry *ie)
159 {
160 	return (size_t)(ie->flags & GOT_FILEIDX_F_PATH_LEN);
161 }
162 
163 uint32_t
164 got_fileindex_entry_stage(const struct got_fileindex_entry *ie)
165 {
166 	return ((ie->flags & GOT_FILEIDX_F_STAGE) >> GOT_FILEIDX_F_STAGE_SHIFT);
167 }
168 
169 int
170 got_fileindex_entry_has_blob(struct got_fileindex_entry *ie)
171 {
172 	return (ie->flags & GOT_FILEIDX_F_NO_BLOB) == 0;
173 }
174 
175 int
176 got_fileindex_entry_has_commit(struct got_fileindex_entry *ie)
177 {
178 	return (ie->flags & GOT_FILEIDX_F_NO_COMMIT) == 0;
179 }
180 
181 int
182 got_fileindex_entry_has_file_on_disk(struct got_fileindex_entry *ie)
183 {
184 	return (ie->flags & GOT_FILEIDX_F_NO_FILE_ON_DISK) == 0;
185 }
186 
187 static const struct got_error *
188 add_entry(struct got_fileindex *fileindex, struct got_fileindex_entry *ie)
189 {
190 	if (fileindex->nentries >= GOT_FILEIDX_MAX_ENTRIES)
191 		return got_error(GOT_ERR_NO_SPACE);
192 
193 	RB_INSERT(got_fileindex_tree, &fileindex->entries, ie);
194 	fileindex->nentries++;
195 	return NULL;
196 }
197 
198 const struct got_error *
199 got_fileindex_entry_add(struct got_fileindex *fileindex,
200     struct got_fileindex_entry *ie)
201 {
202 	/* Flag this entry until it gets written out to disk. */
203 	ie->flags |= GOT_FILEIDX_F_NOT_FLUSHED;
204 
205 	return add_entry(fileindex, ie);
206 }
207 
208 void
209 got_fileindex_entry_remove(struct got_fileindex *fileindex,
210     struct got_fileindex_entry *ie)
211 {
212 	RB_REMOVE(got_fileindex_tree, &fileindex->entries, ie);
213 	fileindex->nentries--;
214 }
215 
216 struct got_fileindex_entry *
217 got_fileindex_entry_get(struct got_fileindex *fileindex, const char *path,
218     size_t path_len)
219 {
220 	struct got_fileindex_entry key;
221 	memset(&key, 0, sizeof(key));
222 	key.path = (char *)path;
223 	key.flags = (path_len & GOT_FILEIDX_F_PATH_LEN);
224 	return RB_FIND(got_fileindex_tree, &fileindex->entries, &key);
225 }
226 
227 const struct got_error *
228 got_fileindex_for_each_entry_safe(struct got_fileindex *fileindex,
229     got_fileindex_cb cb, void *cb_arg)
230 {
231 	const struct got_error *err;
232 	struct got_fileindex_entry *ie, *tmp;
233 
234 	RB_FOREACH_SAFE(ie, got_fileindex_tree, &fileindex->entries, tmp) {
235 		err = (*cb)(cb_arg, ie);
236 		if (err)
237 			return err;
238 	}
239 	return NULL;
240 }
241 
242 struct got_fileindex *
243 got_fileindex_alloc(void)
244 {
245 	struct got_fileindex *fileindex;
246 
247 	fileindex = calloc(1, sizeof(*fileindex));
248 	if (fileindex == NULL)
249 		return NULL;
250 
251 	RB_INIT(&fileindex->entries);
252 	return fileindex;
253 }
254 
255 void
256 got_fileindex_free(struct got_fileindex *fileindex)
257 {
258 	struct got_fileindex_entry *ie;
259 
260 	while ((ie = RB_MIN(got_fileindex_tree, &fileindex->entries))) {
261 		RB_REMOVE(got_fileindex_tree, &fileindex->entries, ie);
262 		got_fileindex_entry_free(ie);
263 	}
264 	free(fileindex);
265 }
266 
267 static const struct got_error *
268 write_fileindex_val64(SHA1_CTX *ctx, uint64_t val, FILE *outfile)
269 {
270 	size_t n;
271 
272 	val = htobe64(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_val32(SHA1_CTX *ctx, uint32_t val, FILE *outfile)
282 {
283 	size_t n;
284 
285 	val = htobe32(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_val16(SHA1_CTX *ctx, uint16_t val, FILE *outfile)
295 {
296 	size_t n;
297 
298 	val = htobe16(val);
299 	SHA1Update(ctx, (uint8_t *)&val, sizeof(val));
300 	n = fwrite(&val, 1, sizeof(val), outfile);
301 	if (n != sizeof(val))
302 		return got_ferror(outfile, GOT_ERR_IO);
303 	return NULL;
304 }
305 
306 static const struct got_error *
307 write_fileindex_path(SHA1_CTX *ctx, const char *path, FILE *outfile)
308 {
309 	size_t n, len, pad = 0;
310 	static const uint8_t zero[8] = { 0 };
311 
312 	len = strlen(path);
313 	while ((len + pad) % 8 != 0)
314 		pad++;
315 	if (pad == 0)
316 		pad = 8; /* NUL-terminate */
317 
318 	SHA1Update(ctx, path, len);
319 	n = fwrite(path, 1, len, outfile);
320 	if (n != len)
321 		return got_ferror(outfile, GOT_ERR_IO);
322 	SHA1Update(ctx, zero, pad);
323 	n = fwrite(zero, 1, pad, outfile);
324 	if (n != pad)
325 		return got_ferror(outfile, GOT_ERR_IO);
326 	return NULL;
327 }
328 
329 static const struct got_error *
330 write_fileindex_entry(SHA1_CTX *ctx, struct got_fileindex_entry *ie,
331     FILE *outfile)
332 {
333 	const struct got_error *err;
334 	size_t n;
335 	uint32_t stage;
336 
337 	err = write_fileindex_val64(ctx, ie->ctime_sec, outfile);
338 	if (err)
339 		return err;
340 	err = write_fileindex_val64(ctx, ie->ctime_nsec, outfile);
341 	if (err)
342 		return err;
343 	err = write_fileindex_val64(ctx, ie->mtime_sec, outfile);
344 	if (err)
345 		return err;
346 	err = write_fileindex_val64(ctx, ie->mtime_nsec, outfile);
347 	if (err)
348 		return err;
349 
350 	err = write_fileindex_val32(ctx, ie->uid, outfile);
351 	if (err)
352 		return err;
353 	err = write_fileindex_val32(ctx, ie->gid, outfile);
354 	if (err)
355 		return err;
356 	err = write_fileindex_val32(ctx, ie->size, outfile);
357 	if (err)
358 		return err;
359 
360 	err = write_fileindex_val16(ctx, ie->mode, outfile);
361 	if (err)
362 		return err;
363 
364 	SHA1Update(ctx, ie->blob_sha1, SHA1_DIGEST_LENGTH);
365 	n = fwrite(ie->blob_sha1, 1, SHA1_DIGEST_LENGTH, outfile);
366 	if (n != SHA1_DIGEST_LENGTH)
367 		return got_ferror(outfile, GOT_ERR_IO);
368 
369 	SHA1Update(ctx, ie->commit_sha1, SHA1_DIGEST_LENGTH);
370 	n = fwrite(ie->commit_sha1, 1, SHA1_DIGEST_LENGTH, outfile);
371 	if (n != SHA1_DIGEST_LENGTH)
372 		return got_ferror(outfile, GOT_ERR_IO);
373 
374 	err = write_fileindex_val32(ctx, ie->flags, outfile);
375 	if (err)
376 		return err;
377 
378 	err = write_fileindex_path(ctx, ie->path, outfile);
379 	if (err)
380 		return err;
381 
382 	stage = got_fileindex_entry_stage(ie);
383 	if (stage == GOT_FILEIDX_STAGE_MODIFY ||
384 	    stage == GOT_FILEIDX_STAGE_ADD) {
385 		SHA1Update(ctx, ie->staged_blob_sha1, SHA1_DIGEST_LENGTH);
386 		n = fwrite(ie->staged_blob_sha1, 1, SHA1_DIGEST_LENGTH,
387 		    outfile);
388 		if (n != SHA1_DIGEST_LENGTH)
389 			return got_ferror(outfile, GOT_ERR_IO);
390 	}
391 
392 	return NULL;
393 }
394 
395 const struct got_error *
396 got_fileindex_write(struct got_fileindex *fileindex, FILE *outfile)
397 {
398 	const struct got_error *err = NULL;
399 	struct got_fileindex_hdr hdr;
400 	SHA1_CTX ctx;
401 	uint8_t sha1[SHA1_DIGEST_LENGTH];
402 	size_t n;
403 	struct got_fileindex_entry *ie;
404 
405 	SHA1Init(&ctx);
406 
407 	hdr.signature = htobe32(GOT_FILE_INDEX_SIGNATURE);
408 	hdr.version = htobe32(GOT_FILE_INDEX_VERSION);
409 	hdr.nentries = htobe32(fileindex->nentries);
410 
411 	SHA1Update(&ctx, (uint8_t *)&hdr.signature, sizeof(hdr.signature));
412 	SHA1Update(&ctx, (uint8_t *)&hdr.version, sizeof(hdr.version));
413 	SHA1Update(&ctx, (uint8_t *)&hdr.nentries, sizeof(hdr.nentries));
414 	n = fwrite(&hdr.signature, 1, sizeof(hdr.signature), outfile);
415 	if (n != sizeof(hdr.signature))
416 		return got_ferror(outfile, GOT_ERR_IO);
417 	n = fwrite(&hdr.version, 1, sizeof(hdr.version), outfile);
418 	if (n != sizeof(hdr.version))
419 		return got_ferror(outfile, GOT_ERR_IO);
420 	n = fwrite(&hdr.nentries, 1, sizeof(hdr.nentries), outfile);
421 	if (n != sizeof(hdr.nentries))
422 		return got_ferror(outfile, GOT_ERR_IO);
423 
424 	RB_FOREACH(ie, got_fileindex_tree, &fileindex->entries) {
425 		ie->flags &= ~GOT_FILEIDX_F_NOT_FLUSHED;
426 		err = write_fileindex_entry(&ctx, ie, outfile);
427 		if (err)
428 			return err;
429 	}
430 
431 	SHA1Final(sha1, &ctx);
432 	n = fwrite(sha1, 1, sizeof(sha1), outfile);
433 	if (n != sizeof(sha1))
434 		return got_ferror(outfile, GOT_ERR_IO);
435 
436 	if (fflush(outfile) != 0)
437 		return got_error_from_errno("fflush");
438 
439 	return NULL;
440 }
441 
442 static const struct got_error *
443 read_fileindex_val64(uint64_t *val, SHA1_CTX *ctx, FILE *infile)
444 {
445 	size_t n;
446 
447 	n = fread(val, 1, sizeof(*val), infile);
448 	if (n != sizeof(*val))
449 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
450 	SHA1Update(ctx, (uint8_t *)val, sizeof(*val));
451 	*val = be64toh(*val);
452 	return NULL;
453 }
454 
455 static const struct got_error *
456 read_fileindex_val32(uint32_t *val, SHA1_CTX *ctx, FILE *infile)
457 {
458 	size_t n;
459 
460 	n = fread(val, 1, sizeof(*val), infile);
461 	if (n != sizeof(*val))
462 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
463 	SHA1Update(ctx, (uint8_t *)val, sizeof(*val));
464 	*val = be32toh(*val);
465 	return NULL;
466 }
467 
468 static const struct got_error *
469 read_fileindex_val16(uint16_t *val, SHA1_CTX *ctx, FILE *infile)
470 {
471 	size_t n;
472 
473 	n = fread(val, 1, sizeof(*val), infile);
474 	if (n != sizeof(*val))
475 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
476 	SHA1Update(ctx, (uint8_t *)val, sizeof(*val));
477 	*val = be16toh(*val);
478 	return NULL;
479 }
480 
481 static const struct got_error *
482 read_fileindex_path(char **path, SHA1_CTX *ctx, FILE *infile)
483 {
484 	const struct got_error *err = NULL;
485 	const size_t chunk_size = 8;
486 	size_t n, len = 0, totlen = chunk_size;
487 
488 	*path = malloc(totlen);
489 	if (*path == NULL)
490 		return got_error_from_errno("malloc");
491 
492 	do {
493 		if (len + chunk_size > totlen) {
494 			char *p = reallocarray(*path, totlen + chunk_size, 1);
495 			if (p == NULL) {
496 				err = got_error_from_errno("reallocarray");
497 				break;
498 			}
499 			totlen += chunk_size;
500 			*path = p;
501 		}
502 		n = fread(*path + len, 1, chunk_size, infile);
503 		if (n != chunk_size) {
504 			err = got_ferror(infile, GOT_ERR_FILEIDX_BAD);
505 			break;
506 		}
507 		SHA1Update(ctx, *path + len, chunk_size);
508 		len += chunk_size;
509 	} while (memchr(*path + len - chunk_size, '\0', chunk_size) == NULL);
510 
511 	if (err) {
512 		free(*path);
513 		*path = NULL;
514 	}
515 	return err;
516 }
517 
518 static const struct got_error *
519 read_fileindex_entry(struct got_fileindex_entry **iep, SHA1_CTX *ctx,
520     FILE *infile, uint32_t version)
521 {
522 	const struct got_error *err;
523 	struct got_fileindex_entry *ie;
524 	size_t n;
525 
526 	*iep = NULL;
527 
528 	ie = calloc(1, sizeof(*ie));
529 	if (ie == NULL)
530 		return got_error_from_errno("calloc");
531 
532 	err = read_fileindex_val64(&ie->ctime_sec, ctx, infile);
533 	if (err)
534 		goto done;
535 	err = read_fileindex_val64(&ie->ctime_nsec, ctx, infile);
536 	if (err)
537 		goto done;
538 	err = read_fileindex_val64(&ie->mtime_sec, ctx, infile);
539 	if (err)
540 		goto done;
541 	err = read_fileindex_val64(&ie->mtime_nsec, ctx, infile);
542 	if (err)
543 		goto done;
544 
545 	err = read_fileindex_val32(&ie->uid, ctx, infile);
546 	if (err)
547 		goto done;
548 	err = read_fileindex_val32(&ie->gid, ctx, infile);
549 	if (err)
550 		goto done;
551 	err = read_fileindex_val32(&ie->size, ctx, infile);
552 	if (err)
553 		goto done;
554 
555 	err = read_fileindex_val16(&ie->mode, ctx, infile);
556 	if (err)
557 		goto done;
558 
559 	n = fread(ie->blob_sha1, 1, SHA1_DIGEST_LENGTH, infile);
560 	if (n != SHA1_DIGEST_LENGTH) {
561 		err = got_ferror(infile, GOT_ERR_FILEIDX_BAD);
562 		goto done;
563 	}
564 	SHA1Update(ctx, ie->blob_sha1, SHA1_DIGEST_LENGTH);
565 
566 	n = fread(ie->commit_sha1, 1, SHA1_DIGEST_LENGTH, infile);
567 	if (n != SHA1_DIGEST_LENGTH) {
568 		err = got_ferror(infile, GOT_ERR_FILEIDX_BAD);
569 		goto done;
570 	}
571 	SHA1Update(ctx, ie->commit_sha1, SHA1_DIGEST_LENGTH);
572 
573 	err = read_fileindex_val32(&ie->flags, ctx, infile);
574 	if (err)
575 		goto done;
576 
577 	err = read_fileindex_path(&ie->path, ctx, infile);
578 	if (err)
579 		goto done;
580 
581 	if (version >= 2) {
582 		uint32_t stage = got_fileindex_entry_stage(ie);
583 		if (stage == GOT_FILEIDX_STAGE_MODIFY ||
584 		    stage == GOT_FILEIDX_STAGE_ADD) {
585 			n = fread(ie->staged_blob_sha1, 1, SHA1_DIGEST_LENGTH,
586 			    infile);
587 			if (n != SHA1_DIGEST_LENGTH) {
588 				err = got_ferror(infile, GOT_ERR_FILEIDX_BAD);
589 				goto done;
590 			}
591 			SHA1Update(ctx, ie->staged_blob_sha1, SHA1_DIGEST_LENGTH);
592 		}
593 	} else {
594 		/* GOT_FILE_INDEX_VERSION 1 does not support staging. */
595 		ie->flags &= ~GOT_FILEIDX_F_STAGE;
596 	}
597 
598 done:
599 	if (err)
600 		got_fileindex_entry_free(ie);
601 	else
602 		*iep = ie;
603 	return err;
604 }
605 
606 const struct got_error *
607 got_fileindex_read(struct got_fileindex *fileindex, FILE *infile)
608 {
609 	const struct got_error *err = NULL;
610 	struct got_fileindex_hdr hdr;
611 	SHA1_CTX ctx;
612 	struct got_fileindex_entry *ie;
613 	uint8_t sha1_expected[SHA1_DIGEST_LENGTH];
614 	uint8_t sha1[SHA1_DIGEST_LENGTH];
615 	size_t n;
616 	int i;
617 
618 	SHA1Init(&ctx);
619 
620 	n = fread(&hdr.signature, 1, sizeof(hdr.signature), infile);
621 	if (n != sizeof(hdr.signature)) {
622 		if (n == 0) /* EOF */
623 			return NULL;
624 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
625 	}
626 	n = fread(&hdr.version, 1, sizeof(hdr.version), infile);
627 	if (n != sizeof(hdr.version)) {
628 		if (n == 0) /* EOF */
629 			return NULL;
630 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
631 	}
632 	n = fread(&hdr.nentries, 1, sizeof(hdr.nentries), infile);
633 	if (n != sizeof(hdr.nentries)) {
634 		if (n == 0) /* EOF */
635 			return NULL;
636 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
637 	}
638 
639 	SHA1Update(&ctx, (uint8_t *)&hdr.signature, sizeof(hdr.signature));
640 	SHA1Update(&ctx, (uint8_t *)&hdr.version, sizeof(hdr.version));
641 	SHA1Update(&ctx, (uint8_t *)&hdr.nentries, sizeof(hdr.nentries));
642 
643 	hdr.signature = be32toh(hdr.signature);
644 	hdr.version = be32toh(hdr.version);
645 	hdr.nentries = be32toh(hdr.nentries);
646 
647 	if (hdr.signature != GOT_FILE_INDEX_SIGNATURE)
648 		return got_error(GOT_ERR_FILEIDX_SIG);
649 	if (hdr.version > GOT_FILE_INDEX_VERSION)
650 		return got_error(GOT_ERR_FILEIDX_VER);
651 
652 	for (i = 0; i < hdr.nentries; i++) {
653 		err = read_fileindex_entry(&ie, &ctx, infile, hdr.version);
654 		if (err)
655 			return err;
656 		err = add_entry(fileindex, ie);
657 		if (err)
658 			return err;
659 	}
660 
661 	n = fread(sha1_expected, 1, sizeof(sha1_expected), infile);
662 	if (n != sizeof(sha1_expected))
663 		return got_ferror(infile, GOT_ERR_FILEIDX_BAD);
664 	SHA1Final(sha1, &ctx);
665 	if (memcmp(sha1, sha1_expected, SHA1_DIGEST_LENGTH) != 0)
666 		return got_error(GOT_ERR_FILEIDX_CSUM);
667 
668 	return NULL;
669 }
670 
671 static struct got_fileindex_entry *
672 walk_fileindex(struct got_fileindex *fileindex, struct got_fileindex_entry *ie)
673 {
674 	struct got_fileindex_entry *next;
675 
676 	next = RB_NEXT(got_fileindex_tree, &fileindex->entries, ie);
677 
678 	/* Skip entries which were newly added by diff callbacks. */
679 	while (next && (next->flags & GOT_FILEIDX_F_NOT_FLUSHED))
680 		next = RB_NEXT(got_fileindex_tree, &fileindex->entries, next);
681 
682 	return next;
683 }
684 
685 static const struct got_error *
686 diff_fileindex_tree(struct got_fileindex *, struct got_fileindex_entry **,
687     const struct got_tree_entries *, const char *, const char *,
688     struct got_repository *, struct got_fileindex_diff_tree_cb *, void *);
689 
690 static const struct got_error *
691 walk_tree(struct got_tree_entry **next, struct got_fileindex *fileindex,
692     struct got_fileindex_entry **ie, struct got_tree_entry *te,
693     const char *path, const char *entry_name, struct got_repository *repo,
694     struct got_fileindex_diff_tree_cb *cb, void *cb_arg)
695 {
696 	const struct got_error *err = NULL;
697 
698 	if (S_ISDIR(te->mode)) {
699 		char *subpath;
700 		struct got_tree_object *subtree;
701 
702 		if (asprintf(&subpath, "%s%s%s", path,
703 		    path[0] == '\0' ? "" : "/", te->name) == -1)
704 			return got_error_from_errno("asprintf");
705 
706 		err = got_object_open_as_tree(&subtree, repo, te->id);
707 		if (err) {
708 			free(subpath);
709 			return err;
710 		}
711 
712 		err = diff_fileindex_tree(fileindex, ie,
713 		    got_object_tree_get_entries(subtree), subpath, entry_name,
714 		    repo, cb, cb_arg);
715 		free(subpath);
716 		got_object_tree_close(subtree);
717 		if (err)
718 			return err;
719 	}
720 
721 	*next = SIMPLEQ_NEXT(te, entry);
722 	return NULL;
723 }
724 
725 static const struct got_error *
726 diff_fileindex_tree(struct got_fileindex *fileindex,
727     struct got_fileindex_entry **ie, const struct got_tree_entries *entries,
728     const char *path, const char *entry_name, struct got_repository *repo,
729     struct got_fileindex_diff_tree_cb *cb, void *cb_arg)
730 {
731 	const struct got_error *err = NULL;
732 	struct got_tree_entry *te = NULL;
733 	size_t path_len = strlen(path);
734 	struct got_fileindex_entry *next;
735 
736 	te = SIMPLEQ_FIRST(&entries->head);
737 	while ((*ie && got_path_is_child((*ie)->path, path, path_len)) || te) {
738 		if (te && *ie) {
739 			char *te_path;
740 			int cmp;
741 			if (asprintf(&te_path, "%s/%s", path, te->name) == -1) {
742 				err = got_error_from_errno("asprintf");
743 				break;
744 			}
745 			cmp = got_path_cmp((*ie)->path, te_path,
746 			    got_fileindex_entry_path_len(*ie), strlen(te_path));
747 			free(te_path);
748 			if (cmp == 0) {
749 				if (got_path_is_child((*ie)->path, path,
750 				    path_len) && (entry_name == NULL ||
751 				    strcmp(te->name, entry_name) == 0)) {
752 					err = cb->diff_old_new(cb_arg, *ie, te,
753 					    path);
754 					if (err || entry_name)
755 						break;
756 				}
757 				*ie = walk_fileindex(fileindex, *ie);
758 				err = walk_tree(&te, fileindex, ie, te,
759 				    path, entry_name, repo, cb, cb_arg);
760 			} else if (cmp < 0) {
761 				next = walk_fileindex(fileindex, *ie);
762 				if (got_path_is_child((*ie)->path, path,
763 				    path_len) && (entry_name == NULL ||
764 				    strcmp(te->name, entry_name) == 0)) {
765 					err = cb->diff_old(cb_arg, *ie, path);
766 					if (err || entry_name)
767 						break;
768 				}
769 				*ie = next;
770 			} else {
771 				if ((entry_name == NULL ||
772 				    strcmp(te->name, entry_name) == 0)) {
773 					err = cb->diff_new(cb_arg, te, path);
774 					if (err || entry_name)
775 						break;
776 				}
777 				err = walk_tree(&te, fileindex, ie, te,
778 				    path, entry_name, repo, cb, cb_arg);
779 			}
780 			if (err)
781 				break;
782 		} else if (*ie) {
783 			next = walk_fileindex(fileindex, *ie);
784 			if (got_path_is_child((*ie)->path, path, path_len) &&
785 			    (entry_name == NULL ||
786 			    strcmp(te->name, entry_name) == 0)) {
787 				err = cb->diff_old(cb_arg, *ie, path);
788 				if (err || entry_name)
789 					break;
790 			}
791 			*ie = next;
792 		} else if (te) {
793 			if (entry_name == NULL ||
794 			    strcmp(te->name, entry_name) == 0) {
795 				err = cb->diff_new(cb_arg, te, path);
796 				if (err || entry_name)
797 					break;
798 			}
799 			err = walk_tree(&te, fileindex, ie, te, path,
800 			    entry_name, repo, cb, cb_arg);
801 			if (err)
802 				break;
803 		}
804 	}
805 
806 	return err;
807 }
808 
809 const struct got_error *
810 got_fileindex_diff_tree(struct got_fileindex *fileindex,
811     struct got_tree_object *tree, const char *path, const char *entry_name,
812     struct got_repository *repo,
813     struct got_fileindex_diff_tree_cb *cb, void *cb_arg)
814 {
815 	struct got_fileindex_entry *ie;
816 	ie = RB_MIN(got_fileindex_tree, &fileindex->entries);
817 	while (ie && !got_path_is_child(ie->path, path, strlen(path)))
818 		ie = walk_fileindex(fileindex, ie);
819 	return diff_fileindex_tree(fileindex, &ie,
820 	    got_object_tree_get_entries(tree), path, entry_name, repo,
821 	    cb, cb_arg);
822 }
823 
824 static const struct got_error *
825 diff_fileindex_dir(struct got_fileindex *, struct got_fileindex_entry **,
826     struct got_pathlist_head *, const char *, const char *,
827     struct got_repository *, struct got_fileindex_diff_dir_cb *, void *);
828 
829 static const struct got_error *
830 read_dirlist(struct got_pathlist_head *dirlist, DIR *dir, const char *path)
831 {
832 	const struct got_error *err = NULL;
833 	struct got_pathlist_entry *new = NULL;
834 	struct dirent *dep = NULL;
835 	struct dirent *de = NULL;
836 
837 	for (;;) {
838 		de = malloc(sizeof(struct dirent) + NAME_MAX + 1);
839 		if (de == NULL) {
840 			err = got_error_from_errno("malloc");
841 			break;
842 		}
843 
844 		if (readdir_r(dir, de, &dep) != 0) {
845 			err = got_error_from_errno("readdir_r");
846 			free(de);
847 			break;
848 		}
849 		if (dep == NULL) {
850 			free(de);
851 			break;
852 		}
853 
854 		if (strcmp(de->d_name, ".") == 0 ||
855 		    strcmp(de->d_name, "..") == 0 ||
856 		    (path[0] == '\0' &&
857 		    strcmp(de->d_name, GOT_WORKTREE_GOT_DIR) == 0)) {
858 			free(de);
859 			continue;
860 		}
861 
862 		err = got_pathlist_insert(&new, dirlist, de->d_name, de);
863 		if (err) {
864 			free(de);
865 			break;
866 		}
867 		if (new == NULL) {
868 			err = got_error(GOT_ERR_DIR_DUP_ENTRY);
869 			free(de);
870 			break;
871 		}
872 	}
873 
874 	return err;
875 }
876 
877 void
878 free_dirlist(struct got_pathlist_head *dirlist)
879 {
880 	struct got_pathlist_entry *dle;
881 
882 	TAILQ_FOREACH(dle, dirlist, entry)
883 		free(dle->data);
884 	got_pathlist_free(dirlist);
885 }
886 
887 static const struct got_error *
888 walk_dir(struct got_pathlist_entry **next, struct got_fileindex *fileindex,
889     struct got_fileindex_entry **ie, struct got_pathlist_entry *dle,
890     const char *path, const char *rootpath, struct got_repository *repo,
891     struct got_fileindex_diff_dir_cb *cb, void *cb_arg)
892 {
893 	const struct got_error *err = NULL;
894 	struct dirent *de = dle->data;
895 
896 	*next = NULL;
897 
898 	if (de->d_type == DT_DIR) {
899 		char *subpath;
900 		char *subdirpath;
901 		DIR *subdir;
902 		struct got_pathlist_head subdirlist;
903 
904 		TAILQ_INIT(&subdirlist);
905 
906 		if (asprintf(&subpath, "%s%s%s", path,
907 		    path[0] == '\0' ? "" : "/", de->d_name) == -1)
908 			return got_error_from_errno("asprintf");
909 
910 		if (asprintf(&subdirpath, "%s/%s", rootpath, subpath) == -1) {
911 			free(subpath);
912 			return got_error_from_errno("asprintf");
913 		}
914 
915 		subdir = opendir(subdirpath);
916 		if (subdir == NULL) {
917 			free(subpath);
918 			free(subdirpath);
919 			return got_error_from_errno2("opendir", subdirpath);
920 		}
921 
922 		err = read_dirlist(&subdirlist, subdir, subdirpath);
923 		if (err) {
924 			free(subpath);
925 			free(subdirpath);
926 			closedir(subdir);
927 			return err;
928 		}
929 		err = diff_fileindex_dir(fileindex, ie, &subdirlist, rootpath,
930 		    subpath, repo, cb, cb_arg);
931 		free(subpath);
932 		free(subdirpath);
933 		closedir(subdir);
934 		free_dirlist(&subdirlist);
935 		if (err)
936 			return err;
937 	}
938 
939 	*next = TAILQ_NEXT(dle, entry);
940 	return NULL;
941 }
942 
943 static const struct got_error *
944 diff_fileindex_dir(struct got_fileindex *fileindex,
945     struct got_fileindex_entry **ie, struct got_pathlist_head *dirlist,
946     const char *rootpath, const char *path, struct got_repository *repo,
947     struct got_fileindex_diff_dir_cb *cb, void *cb_arg)
948 {
949 	const struct got_error *err = NULL;
950 	struct dirent *de = NULL;
951 	size_t path_len = strlen(path);
952 	struct got_pathlist_entry *dle;
953 
954 	dle = TAILQ_FIRST(dirlist);
955 	while ((*ie && got_path_is_child((*ie)->path, path, path_len)) || dle) {
956 		if (dle && *ie) {
957 			char *de_path;
958 			int cmp;
959 			de = dle->data;
960 			if (asprintf(&de_path, "%s/%s", path,
961 			    de->d_name) == -1) {
962 				err = got_error_from_errno("asprintf");
963 				break;
964 			}
965 			cmp = got_path_cmp((*ie)->path, de_path,
966 			    got_fileindex_entry_path_len(*ie),
967 			    strlen(path) + 1 + de->d_namlen);
968 			free(de_path);
969 			if (cmp == 0) {
970 				err = cb->diff_old_new(cb_arg, *ie, de, path);
971 				if (err)
972 					break;
973 				*ie = walk_fileindex(fileindex, *ie);
974 				err = walk_dir(&dle, fileindex, ie, dle, path,
975 				    rootpath, repo, cb, cb_arg);
976 			} else if (cmp < 0 ) {
977 				err = cb->diff_old(cb_arg, *ie, path);
978 				if (err)
979 					break;
980 				*ie = walk_fileindex(fileindex, *ie);
981 			} else {
982 				err = cb->diff_new(cb_arg, de, path);
983 				if (err)
984 					break;
985 				err = walk_dir(&dle, fileindex, ie, dle, path,
986 				    rootpath, repo, cb, cb_arg);
987 			}
988 			if (err)
989 				break;
990 		} else if (*ie) {
991 			err = cb->diff_old(cb_arg, *ie, path);
992 			if (err)
993 				break;
994 			*ie = walk_fileindex(fileindex, *ie);
995 		} else if (dle) {
996 			de = dle->data;
997 			err = cb->diff_new(cb_arg, de, path);
998 			if (err)
999 				break;
1000 			err = walk_dir(&dle, fileindex, ie, dle, path,
1001 			    rootpath, repo, cb, cb_arg);
1002 			if (err)
1003 				break;
1004 		}
1005 	}
1006 
1007 	return err;
1008 }
1009 
1010 const struct got_error *
1011 got_fileindex_diff_dir(struct got_fileindex *fileindex, DIR *rootdir,
1012     const char *rootpath, const char *path, struct got_repository *repo,
1013     struct got_fileindex_diff_dir_cb *cb, void *cb_arg)
1014 {
1015 	const struct got_error *err;
1016 	struct got_fileindex_entry *ie;
1017 	struct got_pathlist_head dirlist;
1018 
1019 	TAILQ_INIT(&dirlist);
1020 	err = read_dirlist(&dirlist, rootdir, path);
1021 	if (err)
1022 		return err;
1023 	ie = RB_MIN(got_fileindex_tree, &fileindex->entries);
1024 	while (ie && !got_path_is_child(ie->path, path, strlen(path)))
1025 		ie = walk_fileindex(fileindex, ie);
1026 	err = diff_fileindex_dir(fileindex, &ie, &dirlist, rootpath, path,
1027 	    repo, cb, cb_arg);
1028 	free_dirlist(&dirlist);
1029 	return err;
1030 }
1031 
1032 RB_GENERATE(got_fileindex_tree, got_fileindex_entry, entry, got_fileindex_cmp);