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