Merge branch 'lt/tree-2'
[git/git.git] / sha1_file.c
1 /*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 *
6 * This handles basic git sha1 object files - packing, unpacking,
7 * creation etc.
8 */
9 #include "cache.h"
10 #include "delta.h"
11 #include "pack.h"
12 #include "blob.h"
13 #include "commit.h"
14 #include "tag.h"
15 #include "tree.h"
16
17 #ifndef O_NOATIME
18 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
19 #define O_NOATIME 01000000
20 #else
21 #define O_NOATIME 0
22 #endif
23 #endif
24
25 const unsigned char null_sha1[20] = { 0, };
26
27 static unsigned int sha1_file_open_flag = O_NOATIME;
28
29 static unsigned hexval(char c)
30 {
31 if (c >= '0' && c <= '9')
32 return c - '0';
33 if (c >= 'a' && c <= 'f')
34 return c - 'a' + 10;
35 if (c >= 'A' && c <= 'F')
36 return c - 'A' + 10;
37 return ~0;
38 }
39
40 int get_sha1_hex(const char *hex, unsigned char *sha1)
41 {
42 int i;
43 for (i = 0; i < 20; i++) {
44 unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
45 if (val & ~0xff)
46 return -1;
47 *sha1++ = val;
48 hex += 2;
49 }
50 return 0;
51 }
52
53 int adjust_shared_perm(const char *path)
54 {
55 struct stat st;
56 int mode;
57
58 if (!shared_repository)
59 return 0;
60 if (lstat(path, &st) < 0)
61 return -1;
62 mode = st.st_mode;
63 if (mode & S_IRUSR)
64 mode |= S_IRGRP;
65 if (mode & S_IWUSR)
66 mode |= S_IWGRP;
67 if (mode & S_IXUSR)
68 mode |= S_IXGRP;
69 if (S_ISDIR(mode))
70 mode |= S_ISGID;
71 if (chmod(path, mode) < 0)
72 return -2;
73 return 0;
74 }
75
76 int safe_create_leading_directories(char *path)
77 {
78 char *pos = path;
79 struct stat st;
80
81 if (*pos == '/')
82 pos++;
83
84 while (pos) {
85 pos = strchr(pos, '/');
86 if (!pos)
87 break;
88 *pos = 0;
89 if (!stat(path, &st)) {
90 /* path exists */
91 if (!S_ISDIR(st.st_mode)) {
92 *pos = '/';
93 return -3;
94 }
95 }
96 else if (mkdir(path, 0777)) {
97 *pos = '/';
98 return -1;
99 }
100 else if (adjust_shared_perm(path)) {
101 *pos = '/';
102 return -2;
103 }
104 *pos++ = '/';
105 }
106 return 0;
107 }
108
109 char * sha1_to_hex(const unsigned char *sha1)
110 {
111 static int bufno;
112 static char hexbuffer[4][50];
113 static const char hex[] = "0123456789abcdef";
114 char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
115 int i;
116
117 for (i = 0; i < 20; i++) {
118 unsigned int val = *sha1++;
119 *buf++ = hex[val >> 4];
120 *buf++ = hex[val & 0xf];
121 }
122 *buf = '\0';
123
124 return buffer;
125 }
126
127 static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
128 {
129 int i;
130 for (i = 0; i < 20; i++) {
131 static char hex[] = "0123456789abcdef";
132 unsigned int val = sha1[i];
133 char *pos = pathbuf + i*2 + (i > 0);
134 *pos++ = hex[val >> 4];
135 *pos = hex[val & 0xf];
136 }
137 }
138
139 /*
140 * NOTE! This returns a statically allocated buffer, so you have to be
141 * careful about using it. Do a "strdup()" if you need to save the
142 * filename.
143 *
144 * Also note that this returns the location for creating. Reading
145 * SHA1 file can happen from any alternate directory listed in the
146 * DB_ENVIRONMENT environment variable if it is not found in
147 * the primary object database.
148 */
149 char *sha1_file_name(const unsigned char *sha1)
150 {
151 static char *name, *base;
152
153 if (!base) {
154 const char *sha1_file_directory = get_object_directory();
155 int len = strlen(sha1_file_directory);
156 base = xmalloc(len + 60);
157 memcpy(base, sha1_file_directory, len);
158 memset(base+len, 0, 60);
159 base[len] = '/';
160 base[len+3] = '/';
161 name = base + len + 1;
162 }
163 fill_sha1_path(name, sha1);
164 return base;
165 }
166
167 char *sha1_pack_name(const unsigned char *sha1)
168 {
169 static const char hex[] = "0123456789abcdef";
170 static char *name, *base, *buf;
171 int i;
172
173 if (!base) {
174 const char *sha1_file_directory = get_object_directory();
175 int len = strlen(sha1_file_directory);
176 base = xmalloc(len + 60);
177 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
178 name = base + len + 11;
179 }
180
181 buf = name;
182
183 for (i = 0; i < 20; i++) {
184 unsigned int val = *sha1++;
185 *buf++ = hex[val >> 4];
186 *buf++ = hex[val & 0xf];
187 }
188
189 return base;
190 }
191
192 char *sha1_pack_index_name(const unsigned char *sha1)
193 {
194 static const char hex[] = "0123456789abcdef";
195 static char *name, *base, *buf;
196 int i;
197
198 if (!base) {
199 const char *sha1_file_directory = get_object_directory();
200 int len = strlen(sha1_file_directory);
201 base = xmalloc(len + 60);
202 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
203 name = base + len + 11;
204 }
205
206 buf = name;
207
208 for (i = 0; i < 20; i++) {
209 unsigned int val = *sha1++;
210 *buf++ = hex[val >> 4];
211 *buf++ = hex[val & 0xf];
212 }
213
214 return base;
215 }
216
217 struct alternate_object_database *alt_odb_list;
218 static struct alternate_object_database **alt_odb_tail;
219
220 static void read_info_alternates(const char * alternates, int depth);
221
222 /*
223 * Prepare alternate object database registry.
224 *
225 * The variable alt_odb_list points at the list of struct
226 * alternate_object_database. The elements on this list come from
227 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
228 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
229 * whose contents is similar to that environment variable but can be
230 * LF separated. Its base points at a statically allocated buffer that
231 * contains "/the/directory/corresponding/to/.git/objects/...", while
232 * its name points just after the slash at the end of ".git/objects/"
233 * in the example above, and has enough space to hold 40-byte hex
234 * SHA1, an extra slash for the first level indirection, and the
235 * terminating NUL.
236 */
237 static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
238 {
239 struct stat st;
240 const char *objdir = get_object_directory();
241 struct alternate_object_database *ent;
242 struct alternate_object_database *alt;
243 /* 43 = 40-byte + 2 '/' + terminating NUL */
244 int pfxlen = len;
245 int entlen = pfxlen + 43;
246 int base_len = -1;
247
248 if (*entry != '/' && relative_base) {
249 /* Relative alt-odb */
250 if (base_len < 0)
251 base_len = strlen(relative_base) + 1;
252 entlen += base_len;
253 pfxlen += base_len;
254 }
255 ent = xmalloc(sizeof(*ent) + entlen);
256
257 if (*entry != '/' && relative_base) {
258 memcpy(ent->base, relative_base, base_len - 1);
259 ent->base[base_len - 1] = '/';
260 memcpy(ent->base + base_len, entry, len);
261 }
262 else
263 memcpy(ent->base, entry, pfxlen);
264
265 ent->name = ent->base + pfxlen + 1;
266 ent->base[pfxlen + 3] = '/';
267 ent->base[pfxlen] = ent->base[entlen-1] = 0;
268
269 /* Detect cases where alternate disappeared */
270 if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
271 error("object directory %s does not exist; "
272 "check .git/objects/info/alternates.",
273 ent->base);
274 free(ent);
275 return -1;
276 }
277
278 /* Prevent the common mistake of listing the same
279 * thing twice, or object directory itself.
280 */
281 for (alt = alt_odb_list; alt; alt = alt->next) {
282 if (!memcmp(ent->base, alt->base, pfxlen)) {
283 free(ent);
284 return -1;
285 }
286 }
287 if (!memcmp(ent->base, objdir, pfxlen)) {
288 free(ent);
289 return -1;
290 }
291
292 /* add the alternate entry */
293 *alt_odb_tail = ent;
294 alt_odb_tail = &(ent->next);
295 ent->next = NULL;
296
297 /* recursively add alternates */
298 read_info_alternates(ent->base, depth + 1);
299
300 ent->base[pfxlen] = '/';
301
302 return 0;
303 }
304
305 static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
306 const char *relative_base, int depth)
307 {
308 const char *cp, *last;
309
310 if (depth > 5) {
311 error("%s: ignoring alternate object stores, nesting too deep.",
312 relative_base);
313 return;
314 }
315
316 last = alt;
317 while (last < ep) {
318 cp = last;
319 if (cp < ep && *cp == '#') {
320 while (cp < ep && *cp != sep)
321 cp++;
322 last = cp + 1;
323 continue;
324 }
325 while (cp < ep && *cp != sep)
326 cp++;
327 if (last != cp) {
328 if ((*last != '/') && depth) {
329 error("%s: ignoring relative alternate object store %s",
330 relative_base, last);
331 } else {
332 link_alt_odb_entry(last, cp - last,
333 relative_base, depth);
334 }
335 }
336 while (cp < ep && *cp == sep)
337 cp++;
338 last = cp;
339 }
340 }
341
342 static void read_info_alternates(const char * relative_base, int depth)
343 {
344 char *map;
345 struct stat st;
346 char path[PATH_MAX];
347 int fd;
348
349 sprintf(path, "%s/info/alternates", relative_base);
350 fd = open(path, O_RDONLY);
351 if (fd < 0)
352 return;
353 if (fstat(fd, &st) || (st.st_size == 0)) {
354 close(fd);
355 return;
356 }
357 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
358 close(fd);
359 if (map == MAP_FAILED)
360 return;
361
362 link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth);
363
364 munmap(map, st.st_size);
365 }
366
367 void prepare_alt_odb(void)
368 {
369 char *alt;
370
371 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
372 if (!alt) alt = "";
373
374 if (alt_odb_tail)
375 return;
376 alt_odb_tail = &alt_odb_list;
377 link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL, 0);
378
379 read_info_alternates(get_object_directory(), 0);
380 }
381
382 static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
383 {
384 char *name = sha1_file_name(sha1);
385 struct alternate_object_database *alt;
386
387 if (!stat(name, st))
388 return name;
389 prepare_alt_odb();
390 for (alt = alt_odb_list; alt; alt = alt->next) {
391 name = alt->name;
392 fill_sha1_path(name, sha1);
393 if (!stat(alt->base, st))
394 return alt->base;
395 }
396 return NULL;
397 }
398
399 #define PACK_MAX_SZ (1<<26)
400 static int pack_used_ctr;
401 static unsigned long pack_mapped;
402 struct packed_git *packed_git;
403
404 static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
405 void **idx_map_)
406 {
407 void *idx_map;
408 unsigned int *index;
409 unsigned long idx_size;
410 int nr, i;
411 int fd = open(path, O_RDONLY);
412 struct stat st;
413 if (fd < 0)
414 return -1;
415 if (fstat(fd, &st)) {
416 close(fd);
417 return -1;
418 }
419 idx_size = st.st_size;
420 idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
421 close(fd);
422 if (idx_map == MAP_FAILED)
423 return -1;
424
425 index = idx_map;
426 *idx_map_ = idx_map;
427 *idx_size_ = idx_size;
428
429 /* check index map */
430 if (idx_size < 4*256 + 20 + 20)
431 return error("index file too small");
432 nr = 0;
433 for (i = 0; i < 256; i++) {
434 unsigned int n = ntohl(index[i]);
435 if (n < nr)
436 return error("non-monotonic index");
437 nr = n;
438 }
439
440 /*
441 * Total size:
442 * - 256 index entries 4 bytes each
443 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
444 * - 20-byte SHA1 of the packfile
445 * - 20-byte SHA1 file checksum
446 */
447 if (idx_size != 4*256 + nr * 24 + 20 + 20)
448 return error("wrong index file size");
449
450 return 0;
451 }
452
453 static int unuse_one_packed_git(void)
454 {
455 struct packed_git *p, *lru = NULL;
456
457 for (p = packed_git; p; p = p->next) {
458 if (p->pack_use_cnt || !p->pack_base)
459 continue;
460 if (!lru || p->pack_last_used < lru->pack_last_used)
461 lru = p;
462 }
463 if (!lru)
464 return 0;
465 munmap(lru->pack_base, lru->pack_size);
466 lru->pack_base = NULL;
467 return 1;
468 }
469
470 void unuse_packed_git(struct packed_git *p)
471 {
472 p->pack_use_cnt--;
473 }
474
475 int use_packed_git(struct packed_git *p)
476 {
477 if (!p->pack_size) {
478 struct stat st;
479 // We created the struct before we had the pack
480 stat(p->pack_name, &st);
481 if (!S_ISREG(st.st_mode))
482 die("packfile %s not a regular file", p->pack_name);
483 p->pack_size = st.st_size;
484 }
485 if (!p->pack_base) {
486 int fd;
487 struct stat st;
488 void *map;
489
490 pack_mapped += p->pack_size;
491 while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
492 ; /* nothing */
493 fd = open(p->pack_name, O_RDONLY);
494 if (fd < 0)
495 die("packfile %s cannot be opened", p->pack_name);
496 if (fstat(fd, &st)) {
497 close(fd);
498 die("packfile %s cannot be opened", p->pack_name);
499 }
500 if (st.st_size != p->pack_size)
501 die("packfile %s size mismatch.", p->pack_name);
502 map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
503 close(fd);
504 if (map == MAP_FAILED)
505 die("packfile %s cannot be mapped.", p->pack_name);
506 p->pack_base = map;
507
508 /* Check if the pack file matches with the index file.
509 * this is cheap.
510 */
511 if (memcmp((char*)(p->index_base) + p->index_size - 40,
512 p->pack_base + p->pack_size - 20, 20)) {
513
514 die("packfile %s does not match index.", p->pack_name);
515 }
516 }
517 p->pack_last_used = pack_used_ctr++;
518 p->pack_use_cnt++;
519 return 0;
520 }
521
522 struct packed_git *add_packed_git(char *path, int path_len, int local)
523 {
524 struct stat st;
525 struct packed_git *p;
526 unsigned long idx_size;
527 void *idx_map;
528 unsigned char sha1[20];
529
530 if (check_packed_git_idx(path, &idx_size, &idx_map))
531 return NULL;
532
533 /* do we have a corresponding .pack file? */
534 strcpy(path + path_len - 4, ".pack");
535 if (stat(path, &st) || !S_ISREG(st.st_mode)) {
536 munmap(idx_map, idx_size);
537 return NULL;
538 }
539 /* ok, it looks sane as far as we can check without
540 * actually mapping the pack file.
541 */
542 p = xmalloc(sizeof(*p) + path_len + 2);
543 strcpy(p->pack_name, path);
544 p->index_size = idx_size;
545 p->pack_size = st.st_size;
546 p->index_base = idx_map;
547 p->next = NULL;
548 p->pack_base = NULL;
549 p->pack_last_used = 0;
550 p->pack_use_cnt = 0;
551 p->pack_local = local;
552 if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
553 memcpy(p->sha1, sha1, 20);
554 return p;
555 }
556
557 struct packed_git *parse_pack_index(unsigned char *sha1)
558 {
559 char *path = sha1_pack_index_name(sha1);
560 return parse_pack_index_file(sha1, path);
561 }
562
563 struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path)
564 {
565 struct packed_git *p;
566 unsigned long idx_size;
567 void *idx_map;
568 char *path;
569
570 if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
571 return NULL;
572
573 path = sha1_pack_name(sha1);
574
575 p = xmalloc(sizeof(*p) + strlen(path) + 2);
576 strcpy(p->pack_name, path);
577 p->index_size = idx_size;
578 p->pack_size = 0;
579 p->index_base = idx_map;
580 p->next = NULL;
581 p->pack_base = NULL;
582 p->pack_last_used = 0;
583 p->pack_use_cnt = 0;
584 memcpy(p->sha1, sha1, 20);
585 return p;
586 }
587
588 void install_packed_git(struct packed_git *pack)
589 {
590 pack->next = packed_git;
591 packed_git = pack;
592 }
593
594 static void prepare_packed_git_one(char *objdir, int local)
595 {
596 char path[PATH_MAX];
597 int len;
598 DIR *dir;
599 struct dirent *de;
600
601 sprintf(path, "%s/pack", objdir);
602 len = strlen(path);
603 dir = opendir(path);
604 if (!dir) {
605 if (errno != ENOENT)
606 error("unable to open object pack directory: %s: %s",
607 path, strerror(errno));
608 return;
609 }
610 path[len++] = '/';
611 while ((de = readdir(dir)) != NULL) {
612 int namelen = strlen(de->d_name);
613 struct packed_git *p;
614
615 if (strcmp(de->d_name + namelen - 4, ".idx"))
616 continue;
617
618 /* we have .idx. Is it a file we can map? */
619 strcpy(path + len, de->d_name);
620 for (p = packed_git; p; p = p->next) {
621 if (!memcmp(path, p->pack_name, len + namelen - 4))
622 break;
623 }
624 if (p)
625 continue;
626 p = add_packed_git(path, len + namelen, local);
627 if (!p)
628 continue;
629 p->next = packed_git;
630 packed_git = p;
631 }
632 closedir(dir);
633 }
634
635 static int prepare_packed_git_run_once = 0;
636 void prepare_packed_git(void)
637 {
638 struct alternate_object_database *alt;
639
640 if (prepare_packed_git_run_once)
641 return;
642 prepare_packed_git_one(get_object_directory(), 1);
643 prepare_alt_odb();
644 for (alt = alt_odb_list; alt; alt = alt->next) {
645 alt->name[-1] = 0;
646 prepare_packed_git_one(alt->base, 0);
647 alt->name[-1] = '/';
648 }
649 prepare_packed_git_run_once = 1;
650 }
651
652 static void reprepare_packed_git(void)
653 {
654 prepare_packed_git_run_once = 0;
655 prepare_packed_git();
656 }
657
658 int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
659 {
660 char header[100];
661 unsigned char real_sha1[20];
662 SHA_CTX c;
663
664 SHA1_Init(&c);
665 SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
666 SHA1_Update(&c, map, size);
667 SHA1_Final(real_sha1, &c);
668 return memcmp(sha1, real_sha1, 20) ? -1 : 0;
669 }
670
671 static void *map_sha1_file_internal(const unsigned char *sha1,
672 unsigned long *size)
673 {
674 struct stat st;
675 void *map;
676 int fd;
677 char *filename = find_sha1_file(sha1, &st);
678
679 if (!filename) {
680 return NULL;
681 }
682
683 fd = open(filename, O_RDONLY | sha1_file_open_flag);
684 if (fd < 0) {
685 /* See if it works without O_NOATIME */
686 switch (sha1_file_open_flag) {
687 default:
688 fd = open(filename, O_RDONLY);
689 if (fd >= 0)
690 break;
691 /* Fallthrough */
692 case 0:
693 return NULL;
694 }
695
696 /* If it failed once, it will probably fail again.
697 * Stop using O_NOATIME
698 */
699 sha1_file_open_flag = 0;
700 }
701 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
702 close(fd);
703 if (map == MAP_FAILED)
704 return NULL;
705 *size = st.st_size;
706 return map;
707 }
708
709 int unpack_sha1_header(z_stream *stream, void *map, unsigned long mapsize, void *buffer, unsigned long size)
710 {
711 /* Get the data stream */
712 memset(stream, 0, sizeof(*stream));
713 stream->next_in = map;
714 stream->avail_in = mapsize;
715 stream->next_out = buffer;
716 stream->avail_out = size;
717
718 inflateInit(stream);
719 return inflate(stream, 0);
720 }
721
722 static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
723 {
724 int bytes = strlen(buffer) + 1;
725 unsigned char *buf = xmalloc(1+size);
726
727 memcpy(buf, buffer + bytes, stream->total_out - bytes);
728 bytes = stream->total_out - bytes;
729 if (bytes < size) {
730 stream->next_out = buf + bytes;
731 stream->avail_out = size - bytes;
732 while (inflate(stream, Z_FINISH) == Z_OK)
733 /* nothing */;
734 }
735 buf[size] = 0;
736 inflateEnd(stream);
737 return buf;
738 }
739
740 /*
741 * We used to just use "sscanf()", but that's actually way
742 * too permissive for what we want to check. So do an anal
743 * object header parse by hand.
744 */
745 int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
746 {
747 int i;
748 unsigned long size;
749
750 /*
751 * The type can be at most ten bytes (including the
752 * terminating '\0' that we add), and is followed by
753 * a space.
754 */
755 i = 10;
756 for (;;) {
757 char c = *hdr++;
758 if (c == ' ')
759 break;
760 if (!--i)
761 return -1;
762 *type++ = c;
763 }
764 *type = 0;
765
766 /*
767 * The length must follow immediately, and be in canonical
768 * decimal format (ie "010" is not valid).
769 */
770 size = *hdr++ - '0';
771 if (size > 9)
772 return -1;
773 if (size) {
774 for (;;) {
775 unsigned long c = *hdr - '0';
776 if (c > 9)
777 break;
778 hdr++;
779 size = size * 10 + c;
780 }
781 }
782 *sizep = size;
783
784 /*
785 * The length must be followed by a zero byte
786 */
787 return *hdr ? -1 : 0;
788 }
789
790 void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
791 {
792 int ret;
793 z_stream stream;
794 char hdr[8192];
795
796 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
797 if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0)
798 return NULL;
799
800 return unpack_sha1_rest(&stream, hdr, *size);
801 }
802
803 /* forward declaration for a mutually recursive function */
804 static int packed_object_info(struct pack_entry *entry,
805 char *type, unsigned long *sizep);
806
807 static int packed_delta_info(unsigned char *base_sha1,
808 unsigned long delta_size,
809 unsigned long left,
810 char *type,
811 unsigned long *sizep,
812 struct packed_git *p)
813 {
814 struct pack_entry base_ent;
815
816 if (left < 20)
817 die("truncated pack file");
818
819 /* The base entry _must_ be in the same pack */
820 if (!find_pack_entry_one(base_sha1, &base_ent, p))
821 die("failed to find delta-pack base object %s",
822 sha1_to_hex(base_sha1));
823
824 /* We choose to only get the type of the base object and
825 * ignore potentially corrupt pack file that expects the delta
826 * based on a base with a wrong size. This saves tons of
827 * inflate() calls.
828 */
829
830 if (packed_object_info(&base_ent, type, NULL))
831 die("cannot get info for delta-pack base");
832
833 if (sizep) {
834 const unsigned char *data;
835 unsigned char delta_head[64];
836 unsigned long result_size;
837 z_stream stream;
838 int st;
839
840 memset(&stream, 0, sizeof(stream));
841
842 data = stream.next_in = base_sha1 + 20;
843 stream.avail_in = left - 20;
844 stream.next_out = delta_head;
845 stream.avail_out = sizeof(delta_head);
846
847 inflateInit(&stream);
848 st = inflate(&stream, Z_FINISH);
849 inflateEnd(&stream);
850 if ((st != Z_STREAM_END) &&
851 stream.total_out != sizeof(delta_head))
852 die("delta data unpack-initial failed");
853
854 /* Examine the initial part of the delta to figure out
855 * the result size.
856 */
857 data = delta_head;
858
859 /* ignore base size */
860 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
861
862 /* Read the result size */
863 result_size = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
864 *sizep = result_size;
865 }
866 return 0;
867 }
868
869 static unsigned long unpack_object_header(struct packed_git *p, unsigned long offset,
870 enum object_type *type, unsigned long *sizep)
871 {
872 unsigned shift;
873 unsigned char *pack, c;
874 unsigned long size;
875
876 if (offset >= p->pack_size)
877 die("object offset outside of pack file");
878
879 pack = p->pack_base + offset;
880 c = *pack++;
881 offset++;
882 *type = (c >> 4) & 7;
883 size = c & 15;
884 shift = 4;
885 while (c & 0x80) {
886 if (offset >= p->pack_size)
887 die("object offset outside of pack file");
888 c = *pack++;
889 offset++;
890 size += (c & 0x7f) << shift;
891 shift += 7;
892 }
893 *sizep = size;
894 return offset;
895 }
896
897 int check_reuse_pack_delta(struct packed_git *p, unsigned long offset,
898 unsigned char *base, unsigned long *sizep,
899 enum object_type *kindp)
900 {
901 unsigned long ptr;
902 int status = -1;
903
904 use_packed_git(p);
905 ptr = offset;
906 ptr = unpack_object_header(p, ptr, kindp, sizep);
907 if (*kindp != OBJ_DELTA)
908 goto done;
909 memcpy(base, p->pack_base + ptr, 20);
910 status = 0;
911 done:
912 unuse_packed_git(p);
913 return status;
914 }
915
916 void packed_object_info_detail(struct pack_entry *e,
917 char *type,
918 unsigned long *size,
919 unsigned long *store_size,
920 unsigned int *delta_chain_length,
921 unsigned char *base_sha1)
922 {
923 struct packed_git *p = e->p;
924 unsigned long offset;
925 unsigned char *pack;
926 enum object_type kind;
927
928 offset = unpack_object_header(p, e->offset, &kind, size);
929 pack = p->pack_base + offset;
930 if (kind != OBJ_DELTA)
931 *delta_chain_length = 0;
932 else {
933 unsigned int chain_length = 0;
934 if (p->pack_size <= offset + 20)
935 die("pack file %s records an incomplete delta base",
936 p->pack_name);
937 memcpy(base_sha1, pack, 20);
938 do {
939 struct pack_entry base_ent;
940 unsigned long junk;
941
942 find_pack_entry_one(pack, &base_ent, p);
943 offset = unpack_object_header(p, base_ent.offset,
944 &kind, &junk);
945 pack = p->pack_base + offset;
946 chain_length++;
947 } while (kind == OBJ_DELTA);
948 *delta_chain_length = chain_length;
949 }
950 switch (kind) {
951 case OBJ_COMMIT:
952 strcpy(type, commit_type);
953 break;
954 case OBJ_TREE:
955 strcpy(type, tree_type);
956 break;
957 case OBJ_BLOB:
958 strcpy(type, blob_type);
959 break;
960 case OBJ_TAG:
961 strcpy(type, tag_type);
962 break;
963 default:
964 die("corrupted pack file %s containing object of kind %d",
965 p->pack_name, kind);
966 }
967 *store_size = 0; /* notyet */
968 }
969
970 static int packed_object_info(struct pack_entry *entry,
971 char *type, unsigned long *sizep)
972 {
973 struct packed_git *p = entry->p;
974 unsigned long offset, size, left;
975 unsigned char *pack;
976 enum object_type kind;
977 int retval;
978
979 if (use_packed_git(p))
980 die("cannot map packed file");
981
982 offset = unpack_object_header(p, entry->offset, &kind, &size);
983 pack = p->pack_base + offset;
984 left = p->pack_size - offset;
985
986 switch (kind) {
987 case OBJ_DELTA:
988 retval = packed_delta_info(pack, size, left, type, sizep, p);
989 unuse_packed_git(p);
990 return retval;
991 case OBJ_COMMIT:
992 strcpy(type, commit_type);
993 break;
994 case OBJ_TREE:
995 strcpy(type, tree_type);
996 break;
997 case OBJ_BLOB:
998 strcpy(type, blob_type);
999 break;
1000 case OBJ_TAG:
1001 strcpy(type, tag_type);
1002 break;
1003 default:
1004 die("corrupted pack file %s containing object of kind %d",
1005 p->pack_name, kind);
1006 }
1007 if (sizep)
1008 *sizep = size;
1009 unuse_packed_git(p);
1010 return 0;
1011 }
1012
1013 /* forward declaration for a mutually recursive function */
1014 static void *unpack_entry(struct pack_entry *, char *, unsigned long *);
1015
1016 static void *unpack_delta_entry(unsigned char *base_sha1,
1017 unsigned long delta_size,
1018 unsigned long left,
1019 char *type,
1020 unsigned long *sizep,
1021 struct packed_git *p)
1022 {
1023 struct pack_entry base_ent;
1024 void *data, *delta_data, *result, *base;
1025 unsigned long data_size, result_size, base_size;
1026 z_stream stream;
1027 int st;
1028
1029 if (left < 20)
1030 die("truncated pack file");
1031
1032 /* The base entry _must_ be in the same pack */
1033 if (!find_pack_entry_one(base_sha1, &base_ent, p))
1034 die("failed to find delta-pack base object %s",
1035 sha1_to_hex(base_sha1));
1036 base = unpack_entry_gently(&base_ent, type, &base_size);
1037 if (!base)
1038 die("failed to read delta-pack base object %s",
1039 sha1_to_hex(base_sha1));
1040
1041 data = base_sha1 + 20;
1042 data_size = left - 20;
1043 delta_data = xmalloc(delta_size);
1044
1045 memset(&stream, 0, sizeof(stream));
1046
1047 stream.next_in = data;
1048 stream.avail_in = data_size;
1049 stream.next_out = delta_data;
1050 stream.avail_out = delta_size;
1051
1052 inflateInit(&stream);
1053 st = inflate(&stream, Z_FINISH);
1054 inflateEnd(&stream);
1055 if ((st != Z_STREAM_END) || stream.total_out != delta_size)
1056 die("delta data unpack failed");
1057
1058 result = patch_delta(base, base_size,
1059 delta_data, delta_size,
1060 &result_size);
1061 if (!result)
1062 die("failed to apply delta");
1063 free(delta_data);
1064 free(base);
1065 *sizep = result_size;
1066 return result;
1067 }
1068
1069 static void *unpack_non_delta_entry(unsigned char *data,
1070 unsigned long size,
1071 unsigned long left)
1072 {
1073 int st;
1074 z_stream stream;
1075 unsigned char *buffer;
1076
1077 buffer = xmalloc(size + 1);
1078 buffer[size] = 0;
1079 memset(&stream, 0, sizeof(stream));
1080 stream.next_in = data;
1081 stream.avail_in = left;
1082 stream.next_out = buffer;
1083 stream.avail_out = size;
1084
1085 inflateInit(&stream);
1086 st = inflate(&stream, Z_FINISH);
1087 inflateEnd(&stream);
1088 if ((st != Z_STREAM_END) || stream.total_out != size) {
1089 free(buffer);
1090 return NULL;
1091 }
1092
1093 return buffer;
1094 }
1095
1096 static void *unpack_entry(struct pack_entry *entry,
1097 char *type, unsigned long *sizep)
1098 {
1099 struct packed_git *p = entry->p;
1100 void *retval;
1101
1102 if (use_packed_git(p))
1103 die("cannot map packed file");
1104 retval = unpack_entry_gently(entry, type, sizep);
1105 unuse_packed_git(p);
1106 if (!retval)
1107 die("corrupted pack file %s", p->pack_name);
1108 return retval;
1109 }
1110
1111 /* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
1112 void *unpack_entry_gently(struct pack_entry *entry,
1113 char *type, unsigned long *sizep)
1114 {
1115 struct packed_git *p = entry->p;
1116 unsigned long offset, size, left;
1117 unsigned char *pack;
1118 enum object_type kind;
1119 void *retval;
1120
1121 offset = unpack_object_header(p, entry->offset, &kind, &size);
1122 pack = p->pack_base + offset;
1123 left = p->pack_size - offset;
1124 switch (kind) {
1125 case OBJ_DELTA:
1126 retval = unpack_delta_entry(pack, size, left, type, sizep, p);
1127 return retval;
1128 case OBJ_COMMIT:
1129 strcpy(type, commit_type);
1130 break;
1131 case OBJ_TREE:
1132 strcpy(type, tree_type);
1133 break;
1134 case OBJ_BLOB:
1135 strcpy(type, blob_type);
1136 break;
1137 case OBJ_TAG:
1138 strcpy(type, tag_type);
1139 break;
1140 default:
1141 return NULL;
1142 }
1143 *sizep = size;
1144 retval = unpack_non_delta_entry(pack, size, left);
1145 return retval;
1146 }
1147
1148 int num_packed_objects(const struct packed_git *p)
1149 {
1150 /* See check_packed_git_idx() */
1151 return (p->index_size - 20 - 20 - 4*256) / 24;
1152 }
1153
1154 int nth_packed_object_sha1(const struct packed_git *p, int n,
1155 unsigned char* sha1)
1156 {
1157 void *index = p->index_base + 256;
1158 if (n < 0 || num_packed_objects(p) <= n)
1159 return -1;
1160 memcpy(sha1, (index + 24 * n + 4), 20);
1161 return 0;
1162 }
1163
1164 int find_pack_entry_one(const unsigned char *sha1,
1165 struct pack_entry *e, struct packed_git *p)
1166 {
1167 unsigned int *level1_ofs = p->index_base;
1168 int hi = ntohl(level1_ofs[*sha1]);
1169 int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
1170 void *index = p->index_base + 256;
1171
1172 do {
1173 int mi = (lo + hi) / 2;
1174 int cmp = memcmp(index + 24 * mi + 4, sha1, 20);
1175 if (!cmp) {
1176 e->offset = ntohl(*((unsigned int *)(index + 24 * mi)));
1177 memcpy(e->sha1, sha1, 20);
1178 e->p = p;
1179 return 1;
1180 }
1181 if (cmp > 0)
1182 hi = mi;
1183 else
1184 lo = mi+1;
1185 } while (lo < hi);
1186 return 0;
1187 }
1188
1189 static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1190 {
1191 struct packed_git *p;
1192 prepare_packed_git();
1193
1194 for (p = packed_git; p; p = p->next) {
1195 if (find_pack_entry_one(sha1, e, p))
1196 return 1;
1197 }
1198 return 0;
1199 }
1200
1201 struct packed_git *find_sha1_pack(const unsigned char *sha1,
1202 struct packed_git *packs)
1203 {
1204 struct packed_git *p;
1205 struct pack_entry e;
1206
1207 for (p = packs; p; p = p->next) {
1208 if (find_pack_entry_one(sha1, &e, p))
1209 return p;
1210 }
1211 return NULL;
1212
1213 }
1214
1215 int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
1216 {
1217 int status;
1218 unsigned long mapsize, size;
1219 void *map;
1220 z_stream stream;
1221 char hdr[128];
1222
1223 map = map_sha1_file_internal(sha1, &mapsize);
1224 if (!map) {
1225 struct pack_entry e;
1226
1227 if (find_pack_entry(sha1, &e))
1228 return packed_object_info(&e, type, sizep);
1229 reprepare_packed_git();
1230 if (find_pack_entry(sha1, &e))
1231 return packed_object_info(&e, type, sizep);
1232 return error("unable to find %s", sha1_to_hex(sha1));
1233 }
1234 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1235 status = error("unable to unpack %s header",
1236 sha1_to_hex(sha1));
1237 if (parse_sha1_header(hdr, type, &size) < 0)
1238 status = error("unable to parse %s header", sha1_to_hex(sha1));
1239 else {
1240 status = 0;
1241 if (sizep)
1242 *sizep = size;
1243 }
1244 inflateEnd(&stream);
1245 munmap(map, mapsize);
1246 return status;
1247 }
1248
1249 static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size)
1250 {
1251 struct pack_entry e;
1252
1253 if (!find_pack_entry(sha1, &e)) {
1254 error("cannot read sha1_file for %s", sha1_to_hex(sha1));
1255 return NULL;
1256 }
1257 return unpack_entry(&e, type, size);
1258 }
1259
1260 void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
1261 {
1262 unsigned long mapsize;
1263 void *map, *buf;
1264 struct pack_entry e;
1265
1266 if (find_pack_entry(sha1, &e))
1267 return read_packed_sha1(sha1, type, size);
1268 map = map_sha1_file_internal(sha1, &mapsize);
1269 if (map) {
1270 buf = unpack_sha1_file(map, mapsize, type, size);
1271 munmap(map, mapsize);
1272 return buf;
1273 }
1274 reprepare_packed_git();
1275 if (find_pack_entry(sha1, &e))
1276 return read_packed_sha1(sha1, type, size);
1277 return NULL;
1278 }
1279
1280 void *read_object_with_reference(const unsigned char *sha1,
1281 const char *required_type,
1282 unsigned long *size,
1283 unsigned char *actual_sha1_return)
1284 {
1285 char type[20];
1286 void *buffer;
1287 unsigned long isize;
1288 unsigned char actual_sha1[20];
1289
1290 memcpy(actual_sha1, sha1, 20);
1291 while (1) {
1292 int ref_length = -1;
1293 const char *ref_type = NULL;
1294
1295 buffer = read_sha1_file(actual_sha1, type, &isize);
1296 if (!buffer)
1297 return NULL;
1298 if (!strcmp(type, required_type)) {
1299 *size = isize;
1300 if (actual_sha1_return)
1301 memcpy(actual_sha1_return, actual_sha1, 20);
1302 return buffer;
1303 }
1304 /* Handle references */
1305 else if (!strcmp(type, commit_type))
1306 ref_type = "tree ";
1307 else if (!strcmp(type, tag_type))
1308 ref_type = "object ";
1309 else {
1310 free(buffer);
1311 return NULL;
1312 }
1313 ref_length = strlen(ref_type);
1314
1315 if (memcmp(buffer, ref_type, ref_length) ||
1316 get_sha1_hex(buffer + ref_length, actual_sha1)) {
1317 free(buffer);
1318 return NULL;
1319 }
1320 free(buffer);
1321 /* Now we have the ID of the referred-to object in
1322 * actual_sha1. Check again. */
1323 }
1324 }
1325
1326 char *write_sha1_file_prepare(void *buf,
1327 unsigned long len,
1328 const char *type,
1329 unsigned char *sha1,
1330 unsigned char *hdr,
1331 int *hdrlen)
1332 {
1333 SHA_CTX c;
1334
1335 /* Generate the header */
1336 *hdrlen = sprintf((char *)hdr, "%s %lu", type, len)+1;
1337
1338 /* Sha1.. */
1339 SHA1_Init(&c);
1340 SHA1_Update(&c, hdr, *hdrlen);
1341 SHA1_Update(&c, buf, len);
1342 SHA1_Final(sha1, &c);
1343
1344 return sha1_file_name(sha1);
1345 }
1346
1347 /*
1348 * Link the tempfile to the final place, possibly creating the
1349 * last directory level as you do so.
1350 *
1351 * Returns the errno on failure, 0 on success.
1352 */
1353 static int link_temp_to_file(const char *tmpfile, char *filename)
1354 {
1355 int ret;
1356
1357 if (!link(tmpfile, filename))
1358 return 0;
1359
1360 /*
1361 * Try to mkdir the last path component if that failed
1362 * with an ENOENT.
1363 *
1364 * Re-try the "link()" regardless of whether the mkdir
1365 * succeeds, since a race might mean that somebody
1366 * else succeeded.
1367 */
1368 ret = errno;
1369 if (ret == ENOENT) {
1370 char *dir = strrchr(filename, '/');
1371 if (dir) {
1372 *dir = 0;
1373 mkdir(filename, 0777);
1374 if (adjust_shared_perm(filename))
1375 return -2;
1376 *dir = '/';
1377 if (!link(tmpfile, filename))
1378 return 0;
1379 ret = errno;
1380 }
1381 }
1382 return ret;
1383 }
1384
1385 /*
1386 * Move the just written object into its final resting place
1387 */
1388 int move_temp_to_file(const char *tmpfile, char *filename)
1389 {
1390 int ret = link_temp_to_file(tmpfile, filename);
1391
1392 /*
1393 * Coda hack - coda doesn't like cross-directory links,
1394 * so we fall back to a rename, which will mean that it
1395 * won't be able to check collisions, but that's not a
1396 * big deal.
1397 *
1398 * The same holds for FAT formatted media.
1399 *
1400 * When this succeeds, we just return 0. We have nothing
1401 * left to unlink.
1402 */
1403 if (ret && ret != EEXIST) {
1404 if (!rename(tmpfile, filename))
1405 return 0;
1406 ret = errno;
1407 }
1408 unlink(tmpfile);
1409 if (ret) {
1410 if (ret != EEXIST) {
1411 fprintf(stderr, "unable to write sha1 filename %s: %s\n", filename, strerror(ret));
1412 return -1;
1413 }
1414 /* FIXME!!! Collision check here ? */
1415 }
1416
1417 return 0;
1418 }
1419
1420 static int write_buffer(int fd, const void *buf, size_t len)
1421 {
1422 while (len) {
1423 ssize_t size;
1424
1425 size = write(fd, buf, len);
1426 if (!size)
1427 return error("file write: disk full");
1428 if (size < 0) {
1429 if (errno == EINTR || errno == EAGAIN)
1430 continue;
1431 return error("file write error (%s)", strerror(errno));
1432 }
1433 len -= size;
1434 buf += size;
1435 }
1436 return 0;
1437 }
1438
1439 int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
1440 {
1441 int size;
1442 unsigned char *compressed;
1443 z_stream stream;
1444 unsigned char sha1[20];
1445 char *filename;
1446 static char tmpfile[PATH_MAX];
1447 unsigned char hdr[50];
1448 int fd, hdrlen;
1449
1450 /* Normally if we have it in the pack then we do not bother writing
1451 * it out into .git/objects/??/?{38} file.
1452 */
1453 filename = write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1454 if (returnsha1)
1455 memcpy(returnsha1, sha1, 20);
1456 if (has_sha1_file(sha1))
1457 return 0;
1458 fd = open(filename, O_RDONLY);
1459 if (fd >= 0) {
1460 /*
1461 * FIXME!!! We might do collision checking here, but we'd
1462 * need to uncompress the old file and check it. Later.
1463 */
1464 close(fd);
1465 return 0;
1466 }
1467
1468 if (errno != ENOENT) {
1469 fprintf(stderr, "sha1 file %s: %s\n", filename, strerror(errno));
1470 return -1;
1471 }
1472
1473 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
1474
1475 fd = mkstemp(tmpfile);
1476 if (fd < 0) {
1477 fprintf(stderr, "unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
1478 return -1;
1479 }
1480
1481 /* Set it up */
1482 memset(&stream, 0, sizeof(stream));
1483 deflateInit(&stream, Z_BEST_COMPRESSION);
1484 size = deflateBound(&stream, len+hdrlen);
1485 compressed = xmalloc(size);
1486
1487 /* Compress it */
1488 stream.next_out = compressed;
1489 stream.avail_out = size;
1490
1491 /* First header.. */
1492 stream.next_in = hdr;
1493 stream.avail_in = hdrlen;
1494 while (deflate(&stream, 0) == Z_OK)
1495 /* nothing */;
1496
1497 /* Then the data itself.. */
1498 stream.next_in = buf;
1499 stream.avail_in = len;
1500 while (deflate(&stream, Z_FINISH) == Z_OK)
1501 /* nothing */;
1502 deflateEnd(&stream);
1503 size = stream.total_out;
1504
1505 if (write_buffer(fd, compressed, size) < 0)
1506 die("unable to write sha1 file");
1507 fchmod(fd, 0444);
1508 close(fd);
1509 free(compressed);
1510
1511 return move_temp_to_file(tmpfile, filename);
1512 }
1513
1514 /*
1515 * We need to unpack and recompress the object for writing
1516 * it out to a different file.
1517 */
1518 static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
1519 {
1520 size_t size;
1521 z_stream stream;
1522 unsigned char *unpacked;
1523 unsigned long len;
1524 char type[20];
1525 char hdr[50];
1526 int hdrlen;
1527 void *buf;
1528
1529 // need to unpack and recompress it by itself
1530 unpacked = read_packed_sha1(sha1, type, &len);
1531
1532 hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
1533
1534 /* Set it up */
1535 memset(&stream, 0, sizeof(stream));
1536 deflateInit(&stream, Z_BEST_COMPRESSION);
1537 size = deflateBound(&stream, len + hdrlen);
1538 buf = xmalloc(size);
1539
1540 /* Compress it */
1541 stream.next_out = buf;
1542 stream.avail_out = size;
1543
1544 /* First header.. */
1545 stream.next_in = (void *)hdr;
1546 stream.avail_in = hdrlen;
1547 while (deflate(&stream, 0) == Z_OK)
1548 /* nothing */;
1549
1550 /* Then the data itself.. */
1551 stream.next_in = unpacked;
1552 stream.avail_in = len;
1553 while (deflate(&stream, Z_FINISH) == Z_OK)
1554 /* nothing */;
1555 deflateEnd(&stream);
1556 free(unpacked);
1557
1558 *objsize = stream.total_out;
1559 return buf;
1560 }
1561
1562 int write_sha1_to_fd(int fd, const unsigned char *sha1)
1563 {
1564 int retval;
1565 unsigned long objsize;
1566 void *buf = map_sha1_file_internal(sha1, &objsize);
1567
1568 if (buf) {
1569 retval = write_buffer(fd, buf, objsize);
1570 munmap(buf, objsize);
1571 return retval;
1572 }
1573
1574 buf = repack_object(sha1, &objsize);
1575 retval = write_buffer(fd, buf, objsize);
1576 free(buf);
1577 return retval;
1578 }
1579
1580 int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
1581 size_t bufsize, size_t *bufposn)
1582 {
1583 char tmpfile[PATH_MAX];
1584 int local;
1585 z_stream stream;
1586 unsigned char real_sha1[20];
1587 unsigned char discard[4096];
1588 int ret;
1589 SHA_CTX c;
1590
1591 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
1592
1593 local = mkstemp(tmpfile);
1594 if (local < 0)
1595 return error("Couldn't open %s for %s",
1596 tmpfile, sha1_to_hex(sha1));
1597
1598 memset(&stream, 0, sizeof(stream));
1599
1600 inflateInit(&stream);
1601
1602 SHA1_Init(&c);
1603
1604 do {
1605 ssize_t size;
1606 if (*bufposn) {
1607 stream.avail_in = *bufposn;
1608 stream.next_in = (unsigned char *) buffer;
1609 do {
1610 stream.next_out = discard;
1611 stream.avail_out = sizeof(discard);
1612 ret = inflate(&stream, Z_SYNC_FLUSH);
1613 SHA1_Update(&c, discard, sizeof(discard) -
1614 stream.avail_out);
1615 } while (stream.avail_in && ret == Z_OK);
1616 if (write_buffer(local, buffer, *bufposn - stream.avail_in) < 0)
1617 die("unable to write sha1 file");
1618 memmove(buffer, buffer + *bufposn - stream.avail_in,
1619 stream.avail_in);
1620 *bufposn = stream.avail_in;
1621 if (ret != Z_OK)
1622 break;
1623 }
1624 size = read(fd, buffer + *bufposn, bufsize - *bufposn);
1625 if (size <= 0) {
1626 close(local);
1627 unlink(tmpfile);
1628 if (!size)
1629 return error("Connection closed?");
1630 perror("Reading from connection");
1631 return -1;
1632 }
1633 *bufposn += size;
1634 } while (1);
1635 inflateEnd(&stream);
1636
1637 close(local);
1638 SHA1_Final(real_sha1, &c);
1639 if (ret != Z_STREAM_END) {
1640 unlink(tmpfile);
1641 return error("File %s corrupted", sha1_to_hex(sha1));
1642 }
1643 if (memcmp(sha1, real_sha1, 20)) {
1644 unlink(tmpfile);
1645 return error("File %s has bad hash", sha1_to_hex(sha1));
1646 }
1647
1648 return move_temp_to_file(tmpfile, sha1_file_name(sha1));
1649 }
1650
1651 int has_pack_index(const unsigned char *sha1)
1652 {
1653 struct stat st;
1654 if (stat(sha1_pack_index_name(sha1), &st))
1655 return 0;
1656 return 1;
1657 }
1658
1659 int has_pack_file(const unsigned char *sha1)
1660 {
1661 struct stat st;
1662 if (stat(sha1_pack_name(sha1), &st))
1663 return 0;
1664 return 1;
1665 }
1666
1667 int has_sha1_pack(const unsigned char *sha1)
1668 {
1669 struct pack_entry e;
1670 return find_pack_entry(sha1, &e);
1671 }
1672
1673 int has_sha1_file(const unsigned char *sha1)
1674 {
1675 struct stat st;
1676 struct pack_entry e;
1677
1678 if (find_pack_entry(sha1, &e))
1679 return 1;
1680 return find_sha1_file(sha1, &st) ? 1 : 0;
1681 }
1682
1683 /*
1684 * reads from fd as long as possible into a supplied buffer of size bytes.
1685 * If neccessary the buffer's size is increased using realloc()
1686 *
1687 * returns 0 if anything went fine and -1 otherwise
1688 *
1689 * NOTE: both buf and size may change, but even when -1 is returned
1690 * you still have to free() it yourself.
1691 */
1692 int read_pipe(int fd, char** return_buf, unsigned long* return_size)
1693 {
1694 char* buf = *return_buf;
1695 unsigned long size = *return_size;
1696 int iret;
1697 unsigned long off = 0;
1698
1699 do {
1700 iret = xread(fd, buf + off, size - off);
1701 if (iret > 0) {
1702 off += iret;
1703 if (off == size) {
1704 size *= 2;
1705 buf = realloc(buf, size);
1706 }
1707 }
1708 } while (iret > 0);
1709
1710 *return_buf = buf;
1711 *return_size = off;
1712
1713 if (iret < 0)
1714 return -1;
1715 return 0;
1716 }
1717
1718 int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
1719 {
1720 unsigned long size = 4096;
1721 char *buf = malloc(size);
1722 int ret;
1723 unsigned char hdr[50];
1724 int hdrlen;
1725
1726 if (read_pipe(fd, &buf, &size)) {
1727 free(buf);
1728 return -1;
1729 }
1730
1731 if (!type)
1732 type = blob_type;
1733 if (write_object)
1734 ret = write_sha1_file(buf, size, type, sha1);
1735 else {
1736 write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);
1737 ret = 0;
1738 }
1739 free(buf);
1740 return ret;
1741 }
1742
1743 int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type)
1744 {
1745 unsigned long size = st->st_size;
1746 void *buf;
1747 int ret;
1748 unsigned char hdr[50];
1749 int hdrlen;
1750
1751 buf = "";
1752 if (size)
1753 buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
1754 close(fd);
1755 if (buf == MAP_FAILED)
1756 return -1;
1757
1758 if (!type)
1759 type = blob_type;
1760 if (write_object)
1761 ret = write_sha1_file(buf, size, type, sha1);
1762 else {
1763 write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);
1764 ret = 0;
1765 }
1766 if (size)
1767 munmap(buf, size);
1768 return ret;
1769 }
1770
1771 int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
1772 {
1773 int fd;
1774 char *target;
1775
1776 switch (st->st_mode & S_IFMT) {
1777 case S_IFREG:
1778 fd = open(path, O_RDONLY);
1779 if (fd < 0)
1780 return error("open(\"%s\"): %s", path,
1781 strerror(errno));
1782 if (index_fd(sha1, fd, st, write_object, NULL) < 0)
1783 return error("%s: failed to insert into database",
1784 path);
1785 break;
1786 case S_IFLNK:
1787 target = xmalloc(st->st_size+1);
1788 if (readlink(path, target, st->st_size+1) != st->st_size) {
1789 char *errstr = strerror(errno);
1790 free(target);
1791 return error("readlink(\"%s\"): %s", path,
1792 errstr);
1793 }
1794 if (!write_object) {
1795 unsigned char hdr[50];
1796 int hdrlen;
1797 write_sha1_file_prepare(target, st->st_size, blob_type,
1798 sha1, hdr, &hdrlen);
1799 } else if (write_sha1_file(target, st->st_size, blob_type, sha1))
1800 return error("%s: failed to insert into database",
1801 path);
1802 free(target);
1803 break;
1804 default:
1805 return error("%s: unsupported file type", path);
1806 }
1807 return 0;
1808 }