Sync with 1.7.0.4
[git/git.git] / sha1_file.c
CommitLineData
0fcfd160
LT
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 */
0fcfd160 9#include "cache.h"
1f688557 10#include "delta.h"
a733cb60 11#include "pack.h"
8e440259
PE
12#include "blob.h"
13#include "commit.h"
14#include "tag.h"
15#include "tree.h"
f35a6d3b 16#include "refs.h"
70f5d5d3 17#include "pack-revindex.h"
628522ec 18#include "sha1-lookup.h"
0fcfd160 19
144bde78
LT
20#ifndef O_NOATIME
21#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
22#define O_NOATIME 01000000
23#else
24#define O_NOATIME 0
25#endif
26#endif
27
e05db0fd
PR
28#ifdef NO_C99_FORMAT
29#define SZ_FMT "lu"
9e42d6a1 30static unsigned long sz_fmt(size_t s) { return (unsigned long)s; }
e05db0fd
PR
31#else
32#define SZ_FMT "zu"
9e42d6a1 33static size_t sz_fmt(size_t s) { return s; }
e05db0fd
PR
34#endif
35
96f1e58f 36const unsigned char null_sha1[20];
88cd621d 37
b2cb9425
JH
38int safe_create_leading_directories(char *path)
39{
8385abfd 40 char *pos = path + offset_1st_component(path);
67d42212
JR
41 struct stat st;
42
b2cb9425
JH
43 while (pos) {
44 pos = strchr(pos, '/');
45 if (!pos)
46 break;
5f0bdf50
JH
47 while (*++pos == '/')
48 ;
49 if (!*pos)
50 break;
51 *--pos = '\0';
67d42212
JR
52 if (!stat(path, &st)) {
53 /* path exists */
54 if (!S_ISDIR(st.st_mode)) {
b2cb9425 55 *pos = '/';
67d42212 56 return -3;
b2cb9425 57 }
457f06d6 58 }
67d42212
JR
59 else if (mkdir(path, 0777)) {
60 *pos = '/';
61 return -1;
62 }
457f06d6
JS
63 else if (adjust_shared_perm(path)) {
64 *pos = '/';
65 return -2;
66 }
b2cb9425
JH
67 *pos++ = '/';
68 }
69 return 0;
70}
723c31fe 71
8e21d63b
JK
72int safe_create_leading_directories_const(const char *path)
73{
74 /* path points to cache entries, so xstrdup before messing with it */
75 char *buf = xstrdup(path);
76 int result = safe_create_leading_directories(buf);
77 free(buf);
78 return result;
79}
80
ace1534d
JH
81static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
82{
83 int i;
84 for (i = 0; i < 20; i++) {
85 static char hex[] = "0123456789abcdef";
86 unsigned int val = sha1[i];
87 char *pos = pathbuf + i*2 + (i > 0);
88 *pos++ = hex[val >> 4];
89 *pos = hex[val & 0xf];
90 }
91}
92
0fcfd160
LT
93/*
94 * NOTE! This returns a statically allocated buffer, so you have to be
790296fd 95 * careful about using it. Do an "xstrdup()" if you need to save the
0fcfd160 96 * filename.
ace1534d
JH
97 *
98 * Also note that this returns the location for creating. Reading
99 * SHA1 file can happen from any alternate directory listed in the
d19938ab 100 * DB_ENVIRONMENT environment variable if it is not found in
ace1534d 101 * the primary object database.
0fcfd160
LT
102 */
103char *sha1_file_name(const unsigned char *sha1)
104{
0fcfd160
LT
105 static char *name, *base;
106
107 if (!base) {
d19938ab 108 const char *sha1_file_directory = get_object_directory();
0fcfd160 109 int len = strlen(sha1_file_directory);
812666c8 110 base = xmalloc(len + 60);
0fcfd160
LT
111 memcpy(base, sha1_file_directory, len);
112 memset(base+len, 0, 60);
113 base[len] = '/';
114 base[len+3] = '/';
115 name = base + len + 1;
116 }
ace1534d 117 fill_sha1_path(name, sha1);
0fcfd160
LT
118 return base;
119}
120
633f43e1 121static char *sha1_get_pack_name(const unsigned char *sha1,
6eec46bd 122 char **name, char **base, const char *which)
bf592c50
DB
123{
124 static const char hex[] = "0123456789abcdef";
633f43e1 125 char *buf;
bf592c50
DB
126 int i;
127
633f43e1 128 if (!*base) {
bf592c50
DB
129 const char *sha1_file_directory = get_object_directory();
130 int len = strlen(sha1_file_directory);
633f43e1 131 *base = xmalloc(len + 60);
6eec46bd
JH
132 sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
133 sha1_file_directory, which);
633f43e1 134 *name = *base + len + 11;
bf592c50
DB
135 }
136
633f43e1 137 buf = *name;
bf592c50
DB
138
139 for (i = 0; i < 20; i++) {
140 unsigned int val = *sha1++;
141 *buf++ = hex[val >> 4];
142 *buf++ = hex[val & 0xf];
143 }
a6080a0a 144
633f43e1 145 return *base;
bf592c50
DB
146}
147
633f43e1 148char *sha1_pack_name(const unsigned char *sha1)
bf592c50 149{
633f43e1 150 static char *name, *base;
bf592c50 151
6eec46bd 152 return sha1_get_pack_name(sha1, &name, &base, "pack");
633f43e1 153}
bf592c50 154
633f43e1
HO
155char *sha1_pack_index_name(const unsigned char *sha1)
156{
157 static char *name, *base;
a6080a0a 158
6eec46bd 159 return sha1_get_pack_name(sha1, &name, &base, "idx");
bf592c50
DB
160}
161
d5a63b99
JH
162struct alternate_object_database *alt_odb_list;
163static struct alternate_object_database **alt_odb_tail;
ace1534d 164
c2f493a4
MW
165static void read_info_alternates(const char * alternates, int depth);
166
ddd5d056
JH
167/*
168 * Prepare alternate object database registry.
d5a63b99
JH
169 *
170 * The variable alt_odb_list points at the list of struct
171 * alternate_object_database. The elements on this list come from
172 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
173 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
174 * whose contents is similar to that environment variable but can be
175 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
176 * contains "/the/directory/corresponding/to/.git/objects/...", while
177 * its name points just after the slash at the end of ".git/objects/"
178 * in the example above, and has enough space to hold 40-byte hex
179 * SHA1, an extra slash for the first level indirection, and the
180 * terminating NUL.
ddd5d056 181 */
c2f493a4 182static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
ace1534d 183{
1494e038 184 const char *objdir = get_object_directory();
c2f493a4
MW
185 struct alternate_object_database *ent;
186 struct alternate_object_database *alt;
187 /* 43 = 40-byte + 2 '/' + terminating NUL */
188 int pfxlen = len;
189 int entlen = pfxlen + 43;
ccfd3e99 190 int base_len = -1;
d5a63b99 191
85dadc38 192 if (!is_absolute_path(entry) && relative_base) {
c2f493a4
MW
193 /* Relative alt-odb */
194 if (base_len < 0)
195 base_len = strlen(relative_base) + 1;
196 entlen += base_len;
197 pfxlen += base_len;
198 }
199 ent = xmalloc(sizeof(*ent) + entlen);
200
85dadc38 201 if (!is_absolute_path(entry) && relative_base) {
c2f493a4
MW
202 memcpy(ent->base, relative_base, base_len - 1);
203 ent->base[base_len - 1] = '/';
204 memcpy(ent->base + base_len, entry, len);
205 }
206 else
207 memcpy(ent->base, entry, pfxlen);
208
209 ent->name = ent->base + pfxlen + 1;
210 ent->base[pfxlen + 3] = '/';
211 ent->base[pfxlen] = ent->base[entlen-1] = 0;
212
213 /* Detect cases where alternate disappeared */
90b4a71c 214 if (!is_directory(ent->base)) {
c2f493a4
MW
215 error("object directory %s does not exist; "
216 "check .git/objects/info/alternates.",
217 ent->base);
218 free(ent);
219 return -1;
220 }
221
222 /* Prevent the common mistake of listing the same
223 * thing twice, or object directory itself.
224 */
225 for (alt = alt_odb_list; alt; alt = alt->next) {
226 if (!memcmp(ent->base, alt->base, pfxlen)) {
227 free(ent);
228 return -1;
229 }
230 }
231 if (!memcmp(ent->base, objdir, pfxlen)) {
232 free(ent);
233 return -1;
234 }
235
236 /* add the alternate entry */
237 *alt_odb_tail = ent;
238 alt_odb_tail = &(ent->next);
239 ent->next = NULL;
240
241 /* recursively add alternates */
242 read_info_alternates(ent->base, depth + 1);
243
244 ent->base[pfxlen] = '/';
245
246 return 0;
247}
248
249static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
250 const char *relative_base, int depth)
251{
252 const char *cp, *last;
253
254 if (depth > 5) {
255 error("%s: ignoring alternate object stores, nesting too deep.",
256 relative_base);
257 return;
258 }
259
d5a63b99 260 last = alt;
9577e7e3
JH
261 while (last < ep) {
262 cp = last;
263 if (cp < ep && *cp == '#') {
264 while (cp < ep && *cp != sep)
265 cp++;
266 last = cp + 1;
267 continue;
268 }
c2f493a4
MW
269 while (cp < ep && *cp != sep)
270 cp++;
d5a63b99 271 if (last != cp) {
85dadc38 272 if (!is_absolute_path(last) && depth) {
c2f493a4
MW
273 error("%s: ignoring relative alternate object store %s",
274 relative_base, last);
275 } else {
276 link_alt_odb_entry(last, cp - last,
277 relative_base, depth);
1494e038 278 }
d5a63b99 279 }
9577e7e3 280 while (cp < ep && *cp == sep)
d5a63b99
JH
281 cp++;
282 last = cp;
9577e7e3 283 }
d5a63b99
JH
284}
285
c2f493a4 286static void read_info_alternates(const char * relative_base, int depth)
d5a63b99 287{
9577e7e3 288 char *map;
dc49cd76 289 size_t mapsz;
d5a63b99 290 struct stat st;
9cb18f56
JM
291 const char alt_file_name[] = "info/alternates";
292 /* Given that relative_base is no longer than PATH_MAX,
293 ensure that "path" has enough space to append "/", the
294 file name, "info/alternates", and a trailing NUL. */
295 char path[PATH_MAX + 1 + sizeof alt_file_name];
c2f493a4 296 int fd;
d5a63b99 297
9cb18f56 298 sprintf(path, "%s/%s", relative_base, alt_file_name);
d5a63b99
JH
299 fd = open(path, O_RDONLY);
300 if (fd < 0)
301 return;
302 if (fstat(fd, &st) || (st.st_size == 0)) {
303 close(fd);
9a217f2a 304 return;
ace1534d 305 }
dc49cd76
SP
306 mapsz = xsize_t(st.st_size);
307 map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0);
d5a63b99 308 close(fd);
d5a63b99 309
dc49cd76 310 link_alt_odb_entries(map, map + mapsz, '\n', relative_base, depth);
c2f493a4 311
dc49cd76 312 munmap(map, mapsz);
ace1534d
JH
313}
314
bef70b22
DB
315void add_to_alternates_file(const char *reference)
316{
317 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
acd3b9ec 318 int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR);
bef70b22
DB
319 char *alt = mkpath("%s/objects\n", reference);
320 write_or_die(fd, alt, strlen(alt));
321 if (commit_lock_file(lock))
322 die("could not close alternates file");
323 if (alt_odb_tail)
324 link_alt_odb_entries(alt, alt + strlen(alt), '\n', NULL, 0);
325}
326
d79796bc
JH
327void foreach_alt_odb(alt_odb_fn fn, void *cb)
328{
329 struct alternate_object_database *ent;
330
331 prepare_alt_odb();
332 for (ent = alt_odb_list; ent; ent = ent->next)
333 if (fn(ent, cb))
334 return;
335}
336
c2f493a4
MW
337void prepare_alt_odb(void)
338{
554fe20d 339 const char *alt;
c2f493a4 340
7dc24aa5
SP
341 if (alt_odb_tail)
342 return;
343
c2f493a4
MW
344 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
345 if (!alt) alt = "";
346
c2f493a4 347 alt_odb_tail = &alt_odb_list;
80ba074f 348 link_alt_odb_entries(alt, alt + strlen(alt), PATH_SEP, NULL, 0);
c2f493a4
MW
349
350 read_info_alternates(get_object_directory(), 0);
351}
352
0f4dc14a 353static int has_loose_object_local(const unsigned char *sha1)
ace1534d 354{
ace1534d 355 char *name = sha1_file_name(sha1);
0f4dc14a
BC
356 return !access(name, F_OK);
357}
ace1534d 358
0f4dc14a
BC
359int has_loose_object_nonlocal(const unsigned char *sha1)
360{
361 struct alternate_object_database *alt;
9a217f2a 362 prepare_alt_odb();
d5a63b99 363 for (alt = alt_odb_list; alt; alt = alt->next) {
0f4dc14a 364 fill_sha1_path(alt->name, sha1);
c529d75a
LT
365 if (!access(alt->base, F_OK))
366 return 1;
ace1534d 367 }
c529d75a 368 return 0;
ace1534d
JH
369}
370
0f4dc14a
BC
371static int has_loose_object(const unsigned char *sha1)
372{
373 return has_loose_object_local(sha1) ||
374 has_loose_object_nonlocal(sha1);
375}
376
60bb8b14 377static unsigned int pack_used_ctr;
a53128b6
SP
378static unsigned int pack_mmap_calls;
379static unsigned int peak_pack_open_windows;
380static unsigned int pack_open_windows;
381static size_t peak_pack_mapped;
60bb8b14 382static size_t pack_mapped;
9a217f2a 383struct packed_git *packed_git;
1f688557 384
b79d18c9 385void pack_report(void)
a53128b6
SP
386{
387 fprintf(stderr,
e05db0fd
PR
388 "pack_report: getpagesize() = %10" SZ_FMT "\n"
389 "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
390 "pack_report: core.packedGitLimit = %10" SZ_FMT "\n",
9e42d6a1
SP
391 sz_fmt(getpagesize()),
392 sz_fmt(packed_git_window_size),
393 sz_fmt(packed_git_limit));
a53128b6
SP
394 fprintf(stderr,
395 "pack_report: pack_used_ctr = %10u\n"
396 "pack_report: pack_mmap_calls = %10u\n"
397 "pack_report: pack_open_windows = %10u / %10u\n"
e05db0fd
PR
398 "pack_report: pack_mapped = "
399 "%10" SZ_FMT " / %10" SZ_FMT "\n",
a53128b6
SP
400 pack_used_ctr,
401 pack_mmap_calls,
402 pack_open_windows, peak_pack_open_windows,
9e42d6a1 403 sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped));
a53128b6
SP
404}
405
42873078 406static int check_packed_git_idx(const char *path, struct packed_git *p)
1f688557
JH
407{
408 void *idx_map;
42873078 409 struct pack_idx_header *hdr;
dc49cd76 410 size_t idx_size;
74e34e1f 411 uint32_t version, nr, i, *index;
e93ec6f9 412 int fd = open(path, O_RDONLY);
1f688557 413 struct stat st;
42873078 414
1f688557
JH
415 if (fd < 0)
416 return -1;
417 if (fstat(fd, &st)) {
418 close(fd);
419 return -1;
420 }
dc49cd76 421 idx_size = xsize_t(st.st_size);
2d88451b
SP
422 if (idx_size < 4 * 256 + 20 + 20) {
423 close(fd);
424 return error("index file %s is too small", path);
425 }
c4712e45 426 idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
1f688557 427 close(fd);
1f688557 428
42873078
NP
429 hdr = idx_map;
430 if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) {
74e34e1f
NP
431 version = ntohl(hdr->idx_version);
432 if (version < 2 || version > 2) {
433 munmap(idx_map, idx_size);
6e1c2344 434 return error("index file %s is version %"PRIu32
74e34e1f
NP
435 " and is not supported by this binary"
436 " (try upgrading GIT to a newer version)",
437 path, version);
438 }
439 } else
440 version = 1;
df1b059d 441
1f688557 442 nr = 0;
42873078 443 index = idx_map;
74e34e1f
NP
444 if (version > 1)
445 index += 2; /* skip index header */
1f688557 446 for (i = 0; i < 256; i++) {
326bf396 447 uint32_t n = ntohl(index[i]);
2d88451b
SP
448 if (n < nr) {
449 munmap(idx_map, idx_size);
df1b059d 450 return error("non-monotonic index %s", path);
2d88451b 451 }
1f688557
JH
452 nr = n;
453 }
454
74e34e1f
NP
455 if (version == 1) {
456 /*
457 * Total size:
458 * - 256 index entries 4 bytes each
459 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
460 * - 20-byte SHA1 of the packfile
461 * - 20-byte SHA1 file checksum
462 */
463 if (idx_size != 4*256 + nr * 24 + 20 + 20) {
464 munmap(idx_map, idx_size);
eef427a0 465 return error("wrong index v1 file size in %s", path);
74e34e1f
NP
466 }
467 } else if (version == 2) {
468 /*
469 * Minimum size:
470 * - 8 bytes of header
471 * - 256 index entries 4 bytes each
472 * - 20-byte sha1 entry * nr
473 * - 4-byte crc entry * nr
474 * - 4-byte offset entry * nr
475 * - 20-byte SHA1 of the packfile
476 * - 20-byte SHA1 file checksum
477 * And after the 4-byte offset table might be a
478 * variable sized table containing 8-byte entries
479 * for offsets larger than 2^31.
480 */
481 unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20;
1164f1e4
LT
482 unsigned long max_size = min_size;
483 if (nr)
484 max_size += (nr - 1)*8;
485 if (idx_size < min_size || idx_size > max_size) {
74e34e1f 486 munmap(idx_map, idx_size);
eef427a0 487 return error("wrong index v2 file size in %s", path);
74e34e1f 488 }
7109c889
JH
489 if (idx_size != min_size &&
490 /*
491 * make sure we can deal with large pack offsets.
492 * 31-bit signed offset won't be enough, neither
493 * 32-bit unsigned one will be.
494 */
495 (sizeof(off_t) <= 4)) {
496 munmap(idx_map, idx_size);
497 return error("pack too large for current definition of off_t in %s", path);
74e34e1f 498 }
2d88451b 499 }
1f688557 500
74e34e1f 501 p->index_version = version;
42873078
NP
502 p->index_data = idx_map;
503 p->index_size = idx_size;
57059091 504 p->num_objects = nr;
1f688557
JH
505 return 0;
506}
507
bc8e478a 508int open_pack_index(struct packed_git *p)
d079837e
SP
509{
510 char *idx_name;
511 int ret;
512
513 if (p->index_data)
514 return 0;
515
516 idx_name = xstrdup(p->pack_name);
517 strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx");
518 ret = check_packed_git_idx(idx_name, p);
519 free(idx_name);
520 return ret;
521}
522
11daf39b
SP
523static void scan_windows(struct packed_git *p,
524 struct packed_git **lru_p,
525 struct pack_window **lru_w,
526 struct pack_window **lru_l)
1f688557 527{
11daf39b
SP
528 struct pack_window *w, *w_l;
529
530 for (w_l = NULL, w = p->windows; w; w = w->next) {
531 if (!w->inuse_cnt) {
532 if (!*lru_w || w->last_used < (*lru_w)->last_used) {
533 *lru_p = p;
534 *lru_w = w;
535 *lru_l = w_l;
54044bf8 536 }
54044bf8 537 }
11daf39b 538 w_l = w;
f9253394 539 }
11daf39b
SP
540}
541
d1efefa4 542static int unuse_one_window(struct packed_git *current, int keep_fd)
11daf39b
SP
543{
544 struct packed_git *p, *lru_p = NULL;
545 struct pack_window *lru_w = NULL, *lru_l = NULL;
546
547 if (current)
548 scan_windows(current, &lru_p, &lru_w, &lru_l);
549 for (p = packed_git; p; p = p->next)
550 scan_windows(p, &lru_p, &lru_w, &lru_l);
54044bf8
SP
551 if (lru_p) {
552 munmap(lru_w->base, lru_w->len);
553 pack_mapped -= lru_w->len;
554 if (lru_l)
555 lru_l->next = lru_w->next;
556 else {
557 lru_p->windows = lru_w->next;
d1efefa4 558 if (!lru_p->windows && lru_p->pack_fd != keep_fd) {
54044bf8
SP
559 close(lru_p->pack_fd);
560 lru_p->pack_fd = -1;
561 }
562 }
563 free(lru_w);
a53128b6 564 pack_open_windows--;
54044bf8
SP
565 return 1;
566 }
567 return 0;
f9253394
JH
568}
569
d1efefa4 570void release_pack_memory(size_t need, int fd)
97bfeb34
SP
571{
572 size_t cur = pack_mapped;
d1efefa4 573 while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd))
97bfeb34
SP
574 ; /* nothing */
575}
576
c9ced051
SP
577void close_pack_windows(struct packed_git *p)
578{
579 while (p->windows) {
580 struct pack_window *w = p->windows;
581
582 if (w->inuse_cnt)
583 die("pack '%s' still has open windows to it",
584 p->pack_name);
585 munmap(w->base, w->len);
586 pack_mapped -= w->len;
587 pack_open_windows--;
588 p->windows = w->next;
589 free(w);
590 }
591}
592
03e79c88 593void unuse_pack(struct pack_window **w_cursor)
f9253394 594{
03e79c88
SP
595 struct pack_window *w = *w_cursor;
596 if (w) {
597 w->inuse_cnt--;
598 *w_cursor = NULL;
599 }
1f688557
JH
600}
601
c74faea1
NP
602/*
603 * This is used by git-repack in case a newly created pack happens to
604 * contain the same set of objects as an existing one. In that case
605 * the resulting file might be different even if its name would be the
606 * same. It is best to close any reference to the old pack before it is
607 * replaced on disk. Of course no index pointers nor windows for given pack
608 * must subsist at this point. If ever objects from this pack are requested
609 * again, the new version of the pack will be reinitialized through
610 * reprepare_packed_git().
611 */
612void free_pack_by_name(const char *pack_name)
613{
614 struct packed_git *p, **pp = &packed_git;
615
616 while (*pp) {
617 p = *pp;
618 if (strcmp(pack_name, p->pack_name) == 0) {
fa3a0c94 619 clear_delta_base_cache();
c74faea1
NP
620 close_pack_windows(p);
621 if (p->pack_fd != -1)
622 close(p->pack_fd);
623 if (p->index_data)
624 munmap((void *)p->index_data, p->index_size);
625 free(p->bad_object_sha1);
626 *pp = p->next;
627 free(p);
628 return;
629 }
630 pp = &p->next;
631 }
632}
633
3cf8b462
SP
634/*
635 * Do not call this directly as this leaks p->pack_fd on error return;
636 * call open_packed_git() instead.
637 */
638static int open_packed_git_1(struct packed_git *p)
1f688557 639{
9bc879c1
SP
640 struct stat st;
641 struct pack_header hdr;
642 unsigned char sha1[20];
643 unsigned char *idx_sha1;
2c039da8 644 long fd_flag;
9bc879c1 645
d079837e
SP
646 if (!p->index_data && open_pack_index(p))
647 return error("packfile %s index unavailable", p->pack_name);
648
9bc879c1 649 p->pack_fd = open(p->pack_name, O_RDONLY);
fd73ccf2
JS
650 while (p->pack_fd < 0 && errno == EMFILE && unuse_one_window(p, -1))
651 p->pack_fd = open(p->pack_name, O_RDONLY);
9bc879c1 652 if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
072db278 653 return -1;
9bc879c1
SP
654
655 /* If we created the struct before we had the pack we lack size. */
bf592c50 656 if (!p->pack_size) {
bf592c50 657 if (!S_ISREG(st.st_mode))
072db278 658 return error("packfile %s not a regular file", p->pack_name);
bf592c50 659 p->pack_size = st.st_size;
9bc879c1 660 } else if (p->pack_size != st.st_size)
072db278 661 return error("packfile %s size changed", p->pack_name);
9bc879c1 662
2c039da8
JH
663 /* We leave these file descriptors open with sliding mmap;
664 * there is no point keeping them open across exec(), though.
665 */
666 fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
667 if (fd_flag < 0)
072db278 668 return error("cannot determine file descriptor flags");
2c039da8
JH
669 fd_flag |= FD_CLOEXEC;
670 if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
072db278 671 return error("cannot set FD_CLOEXEC");
2c039da8 672
9bc879c1 673 /* Verify we recognize this pack file format. */
e6e2bd62 674 if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
072db278 675 return error("file %s is far too short to be a packfile", p->pack_name);
9bc879c1 676 if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
072db278 677 return error("file %s is not a GIT packfile", p->pack_name);
9bc879c1 678 if (!pack_version_ok(hdr.hdr_version))
6e1c2344
RJ
679 return error("packfile %s is version %"PRIu32" and not"
680 " supported (try upgrading GIT to a newer version)",
9bc879c1
SP
681 p->pack_name, ntohl(hdr.hdr_version));
682
683 /* Verify the pack matches its index. */
57059091 684 if (p->num_objects != ntohl(hdr.hdr_entries))
6e1c2344
RJ
685 return error("packfile %s claims to have %"PRIu32" objects"
686 " while index indicates %"PRIu32" objects",
57059091
NP
687 p->pack_name, ntohl(hdr.hdr_entries),
688 p->num_objects);
9bc879c1 689 if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
072db278 690 return error("end of packfile %s is unavailable", p->pack_name);
e6e2bd62 691 if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
072db278 692 return error("packfile %s signature is unavailable", p->pack_name);
42873078 693 idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40;
9bc879c1 694 if (hashcmp(sha1, idx_sha1))
072db278
SP
695 return error("packfile %s does not match index", p->pack_name);
696 return 0;
9bc879c1
SP
697}
698
3cf8b462
SP
699static int open_packed_git(struct packed_git *p)
700{
701 if (!open_packed_git_1(p))
702 return 0;
703 if (p->pack_fd != -1) {
704 close(p->pack_fd);
705 p->pack_fd = -1;
706 }
707 return -1;
708}
709
c4001d92 710static int in_window(struct pack_window *win, off_t offset)
60bb8b14
SP
711{
712 /* We must promise at least 20 bytes (one hash) after the
713 * offset is available from this window, otherwise the offset
714 * is not actually in this window and a different window (which
715 * has that one hash excess) must be used. This is to support
716 * the object header and delta base parsing routines below.
717 */
718 off_t win_off = win->offset;
719 return win_off <= offset
720 && (offset + 20) <= (win_off + win->len);
721}
722
4b25d091 723unsigned char *use_pack(struct packed_git *p,
03e79c88 724 struct pack_window **w_cursor,
c4001d92 725 off_t offset,
03e79c88 726 unsigned int *left)
9bc879c1 727{
60bb8b14 728 struct pack_window *win = *w_cursor;
03e79c88 729
072db278
SP
730 if (p->pack_fd == -1 && open_packed_git(p))
731 die("packfile %s cannot be accessed", p->pack_name);
60bb8b14 732
a9d98a14 733 /* Since packfiles end in a hash of their content and it's
60bb8b14
SP
734 * pointless to ask for an offset into the middle of that
735 * hash, and the in_window function above wouldn't match
736 * don't allow an offset too close to the end of the file.
737 */
738 if (offset > (p->pack_size - 20))
739 die("offset beyond end of packfile (truncated pack?)");
740
741 if (!win || !in_window(win, offset)) {
742 if (win)
743 win->inuse_cnt--;
744 for (win = p->windows; win; win = win->next) {
745 if (in_window(win, offset))
746 break;
747 }
748 if (!win) {
78a28df9 749 size_t window_align = packed_git_window_size / 2;
dc49cd76 750 off_t len;
60bb8b14 751 win = xcalloc(1, sizeof(*win));
78a28df9 752 win->offset = (offset / window_align) * window_align;
dc49cd76
SP
753 len = p->pack_size - win->offset;
754 if (len > packed_git_window_size)
755 len = packed_git_window_size;
756 win->len = (size_t)len;
60bb8b14 757 pack_mapped += win->len;
11daf39b 758 while (packed_git_limit < pack_mapped
d1efefa4 759 && unuse_one_window(p, p->pack_fd))
60bb8b14 760 ; /* nothing */
c4712e45 761 win->base = xmmap(NULL, win->len,
60bb8b14
SP
762 PROT_READ, MAP_PRIVATE,
763 p->pack_fd, win->offset);
764 if (win->base == MAP_FAILED)
73b4e4be
SP
765 die("packfile %s cannot be mapped: %s",
766 p->pack_name,
767 strerror(errno));
a53128b6
SP
768 pack_mmap_calls++;
769 pack_open_windows++;
770 if (pack_mapped > peak_pack_mapped)
771 peak_pack_mapped = pack_mapped;
772 if (pack_open_windows > peak_pack_open_windows)
773 peak_pack_open_windows = pack_open_windows;
60bb8b14
SP
774 win->next = p->windows;
775 p->windows = win;
776 }
1f688557 777 }
03e79c88
SP
778 if (win != *w_cursor) {
779 win->last_used = pack_used_ctr++;
780 win->inuse_cnt++;
781 *w_cursor = win;
782 }
60bb8b14 783 offset -= win->offset;
03e79c88 784 if (left)
dc49cd76 785 *left = win->len - xsize_t(offset);
03e79c88 786 return win->base + offset;
1f688557
JH
787}
788
27d69a46
NP
789static struct packed_git *alloc_packed_git(int extra)
790{
791 struct packed_git *p = xmalloc(sizeof(*p) + extra);
792 memset(p, 0, sizeof(*p));
793 p->pack_fd = -1;
794 return p;
795}
796
42873078 797struct packed_git *add_packed_git(const char *path, int path_len, int local)
1f688557
JH
798{
799 struct stat st;
27d69a46 800 struct packed_git *p = alloc_packed_git(path_len + 2);
1f688557 801
42873078
NP
802 /*
803 * Make sure a corresponding .pack file exists and that
804 * the index looks sane.
805 */
806 path_len -= strlen(".idx");
27d69a46
NP
807 if (path_len < 1) {
808 free(p);
1f688557 809 return NULL;
27d69a46 810 }
42873078 811 memcpy(p->pack_name, path, path_len);
8d25931d
BC
812
813 strcpy(p->pack_name + path_len, ".keep");
814 if (!access(p->pack_name, F_OK))
815 p->pack_keep = 1;
816
42873078 817 strcpy(p->pack_name + path_len, ".pack");
d079837e 818 if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
42873078 819 free(p);
1f688557
JH
820 return NULL;
821 }
42873078 822
1f688557
JH
823 /* ok, it looks sane as far as we can check without
824 * actually mapping the pack file.
825 */
1f688557 826 p->pack_size = st.st_size;
9d835df2 827 p->pack_local = local;
b867092f 828 p->mtime = st.st_mtime;
42873078
NP
829 if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1))
830 hashclr(p->sha1);
1f688557
JH
831 return p;
832}
833
bf592c50 834struct packed_git *parse_pack_index(unsigned char *sha1)
c508df5e 835{
79c6dca4 836 const char *idx_path = sha1_pack_index_name(sha1);
42873078 837 const char *path = sha1_pack_name(sha1);
27d69a46 838 struct packed_git *p = alloc_packed_git(strlen(path) + 1);
bf592c50 839
27d69a46
NP
840 strcpy(p->pack_name, path);
841 hashcpy(p->sha1, sha1);
42873078
NP
842 if (check_packed_git_idx(idx_path, p)) {
843 free(p);
bf592c50 844 return NULL;
42873078 845 }
bf592c50 846
bf592c50
DB
847 return p;
848}
849
850void install_packed_git(struct packed_git *pack)
851{
852 pack->next = packed_git;
853 packed_git = pack;
854}
855
9d835df2 856static void prepare_packed_git_one(char *objdir, int local)
1f688557 857{
9cb18f56
JM
858 /* Ensure that this buffer is large enough so that we can
859 append "/pack/" without clobbering the stack even if
860 strlen(objdir) were PATH_MAX. */
861 char path[PATH_MAX + 1 + 4 + 1 + 1];
1f688557
JH
862 int len;
863 DIR *dir;
864 struct dirent *de;
865
866 sprintf(path, "%s/pack", objdir);
867 len = strlen(path);
868 dir = opendir(path);
fd73ccf2
JS
869 while (!dir && errno == EMFILE && unuse_one_window(packed_git, -1))
870 dir = opendir(path);
b5b16990 871 if (!dir) {
26125f6b 872 if (errno != ENOENT)
bd2afde8 873 error("unable to open object pack directory: %s: %s",
26125f6b 874 path, strerror(errno));
1f688557 875 return;
b5b16990 876 }
1f688557
JH
877 path[len++] = '/';
878 while ((de = readdir(dir)) != NULL) {
879 int namelen = strlen(de->d_name);
880 struct packed_git *p;
881
5bb1cda5 882 if (!has_extension(de->d_name, ".idx"))
1f688557
JH
883 continue;
884
9cb18f56
JM
885 if (len + namelen + 1 > sizeof(path))
886 continue;
887
54a15a8d 888 /* Don't reopen a pack we already have. */
1f688557 889 strcpy(path + len, de->d_name);
86f7780c
JK
890 for (p = packed_git; p; p = p->next) {
891 if (!memcmp(path, p->pack_name, len + namelen - 4))
892 break;
893 }
894 if (p)
895 continue;
54a15a8d
SP
896 /* See if it really is a valid .idx file with corresponding
897 * .pack file that we can map.
898 */
9d835df2 899 p = add_packed_git(path, len + namelen, local);
1f688557
JH
900 if (!p)
901 continue;
625e9421 902 install_packed_git(p);
1f688557 903 }
5b35bcd5 904 closedir(dir);
1f688557
JH
905}
906
b867092f
JH
907static int sort_pack(const void *a_, const void *b_)
908{
909 struct packed_git *a = *((struct packed_git **)a_);
910 struct packed_git *b = *((struct packed_git **)b_);
911 int st;
912
913 /*
914 * Local packs tend to contain objects specific to our
915 * variant of the project than remote ones. In addition,
916 * remote ones could be on a network mounted filesystem.
917 * Favor local ones for these reasons.
918 */
919 st = a->pack_local - b->pack_local;
920 if (st)
921 return -st;
922
923 /*
924 * Younger packs tend to contain more recent objects,
925 * and more recent objects tend to get accessed more
926 * often.
927 */
928 if (a->mtime < b->mtime)
929 return 1;
930 else if (a->mtime == b->mtime)
931 return 0;
932 return -1;
933}
934
935static void rearrange_packed_git(void)
936{
937 struct packed_git **ary, *p;
938 int i, n;
939
940 for (n = 0, p = packed_git; p; p = p->next)
941 n++;
942 if (n < 2)
943 return;
944
945 /* prepare an array of packed_git for easier sorting */
946 ary = xcalloc(n, sizeof(struct packed_git *));
947 for (n = 0, p = packed_git; p; p = p->next)
948 ary[n++] = p;
949
950 qsort(ary, n, sizeof(struct packed_git *), sort_pack);
951
952 /* link them back again */
953 for (i = 0; i < n - 1; i++)
954 ary[i]->next = ary[i + 1];
955 ary[n - 1]->next = NULL;
956 packed_git = ary[0];
957
958 free(ary);
959}
960
637cdd9d 961static int prepare_packed_git_run_once = 0;
9a217f2a 962void prepare_packed_git(void)
1f688557 963{
d5a63b99 964 struct alternate_object_database *alt;
1f688557 965
637cdd9d 966 if (prepare_packed_git_run_once)
1f688557 967 return;
9d835df2 968 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 969 prepare_alt_odb();
d5a63b99 970 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 971 alt->name[-1] = 0;
9d835df2 972 prepare_packed_git_one(alt->base, 0);
1494e038 973 alt->name[-1] = '/';
1f688557 974 }
b867092f 975 rearrange_packed_git();
637cdd9d
JK
976 prepare_packed_git_run_once = 1;
977}
978
fc04c412 979void reprepare_packed_git(void)
637cdd9d 980{
4b480c67 981 discard_revindex();
637cdd9d
JK
982 prepare_packed_git_run_once = 0;
983 prepare_packed_git();
1f688557
JH
984}
985
8eca0b47
NP
986static void mark_bad_packed_object(struct packed_git *p,
987 const unsigned char *sha1)
988{
989 unsigned i;
990 for (i = 0; i < p->num_bad_objects; i++)
991 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
992 return;
993 p->bad_object_sha1 = xrealloc(p->bad_object_sha1, 20 * (p->num_bad_objects + 1));
994 hashcpy(p->bad_object_sha1 + 20 * p->num_bad_objects, sha1);
995 p->num_bad_objects++;
996}
997
ac939109
NP
998static int has_packed_and_bad(const unsigned char *sha1)
999{
1000 struct packed_git *p;
1001 unsigned i;
1002
1003 for (p = packed_git; p; p = p->next)
1004 for (i = 0; i < p->num_bad_objects; i++)
1005 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1006 return 1;
1007 return 0;
1008}
1009
5d6ccf5c 1010int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
0fcfd160
LT
1011{
1012 unsigned char real_sha1[20];
7cfb5f36 1013 hash_sha1_file(map, size, type, real_sha1);
a89fccd2 1014 return hashcmp(sha1, real_sha1) ? -1 : 0;
0fcfd160
LT
1015}
1016
44d1c19e
LT
1017static int git_open_noatime(const char *name)
1018{
1019 static int sha1_file_open_flag = O_NOATIME;
1020 int fd = open(name, O_RDONLY | sha1_file_open_flag);
1021
1022 /* Might the failure be due to O_NOATIME? */
1023 if (fd < 0 && errno != ENOENT && sha1_file_open_flag) {
1024 fd = open(name, O_RDONLY);
1025 if (fd >= 0)
1026 sha1_file_open_flag = 0;
1027 }
1028 return fd;
1029}
1030
1031static int open_sha1_file(const unsigned char *sha1)
1032{
1033 int fd;
1034 char *name = sha1_file_name(sha1);
1035 struct alternate_object_database *alt;
1036
1037 fd = git_open_noatime(name);
1038 if (fd >= 0)
1039 return fd;
1040
1041 prepare_alt_odb();
1042 errno = ENOENT;
1043 for (alt = alt_odb_list; alt; alt = alt->next) {
1044 name = alt->name;
1045 fill_sha1_path(name, sha1);
1046 fd = git_open_noatime(alt->base);
1047 if (fd >= 0)
1048 return fd;
1049 }
1050 return -1;
1051}
1052
4175e9e3 1053static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
0fcfd160 1054{
0fcfd160 1055 void *map;
144bde78 1056 int fd;
ace1534d 1057
44d1c19e
LT
1058 fd = open_sha1_file(sha1);
1059 map = NULL;
1060 if (fd >= 0) {
1061 struct stat st;
0fcfd160 1062
44d1c19e
LT
1063 if (!fstat(fd, &st)) {
1064 *size = xsize_t(st.st_size);
1065 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
144bde78 1066 }
44d1c19e 1067 close(fd);
0fcfd160 1068 }
0fcfd160
LT
1069 return map;
1070}
1071
726f852b 1072static int legacy_loose_object(unsigned char *map)
bb6b8e4f
JH
1073{
1074 unsigned int word;
1075
1076 /*
1077 * Is it a zlib-compressed buffer? If so, the first byte
1078 * must be 0x78 (15-bit window size, deflated), and the
1079 * first 16-bit word is evenly divisible by 31
1080 */
1081 word = (map[0] << 8) + map[1];
1082 if (map[0] == 0x78 && !(word % 31))
1083 return 1;
1084 else
1085 return 0;
1086}
1087
09ded04b
NP
1088unsigned long unpack_object_header_buffer(const unsigned char *buf,
1089 unsigned long len, enum object_type *type, unsigned long *sizep)
c4483576 1090{
ad1ed5ee 1091 unsigned shift;
48fb7deb 1092 unsigned long size, c;
ad1ed5ee
JH
1093 unsigned long used = 0;
1094
1095 c = buf[used++];
1096 *type = (c >> 4) & 7;
1097 size = c & 15;
1098 shift = 4;
1099 while (c & 0x80) {
f630cfda 1100 if (len <= used || bitsizeof(long) <= shift) {
09ded04b 1101 error("bad object header");
ad1ed5ee 1102 return 0;
09ded04b 1103 }
ad1ed5ee
JH
1104 c = buf[used++];
1105 size += (c & 0x7f) << shift;
1106 shift += 7;
1107 }
1108 *sizep = size;
1109 return used;
1110}
1111
1112static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
1113{
1114 unsigned long size, used;
1115 static const char valid_loose_object_type[8] = {
1116 0, /* OBJ_EXT */
1117 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
1118 0, /* "delta" and others are invalid in a loose object */
93821bd9 1119 };
ad1ed5ee 1120 enum object_type type;
93821bd9 1121
c4483576
LT
1122 /* Get the data stream */
1123 memset(stream, 0, sizeof(*stream));
1124 stream->next_in = map;
1125 stream->avail_in = mapsize;
1126 stream->next_out = buffer;
93821bd9
LT
1127 stream->avail_out = bufsiz;
1128
bb6b8e4f 1129 if (legacy_loose_object(map)) {
39c68542
LT
1130 git_inflate_init(stream);
1131 return git_inflate(stream, 0);
93821bd9
LT
1132 }
1133
726f852b
NP
1134
1135 /*
1136 * There used to be a second loose object header format which
1137 * was meant to mimic the in-pack format, allowing for direct
1138 * copy of the object data. This format turned up not to be
1139 * really worth it and we don't write it any longer. But we
1140 * can still read it.
1141 */
09ded04b 1142 used = unpack_object_header_buffer(map, mapsize, &type, &size);
ad1ed5ee 1143 if (!used || !valid_loose_object_type[type])
93821bd9 1144 return -1;
ad1ed5ee
JH
1145 map += used;
1146 mapsize -= used;
93821bd9
LT
1147
1148 /* Set up the stream for the rest.. */
1149 stream->next_in = map;
1150 stream->avail_in = mapsize;
39c68542 1151 git_inflate_init(stream);
93821bd9
LT
1152
1153 /* And generate the fake traditional header */
ad1ed5ee 1154 stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
df843662 1155 typename(type), size);
93821bd9 1156 return 0;
c4483576
LT
1157}
1158
7efbff75 1159static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
5180cacc
LT
1160{
1161 int bytes = strlen(buffer) + 1;
3aee68aa 1162 unsigned char *buf = xmallocz(size);
93821bd9 1163 unsigned long n;
7efbff75 1164 int status = Z_OK;
5180cacc 1165
93821bd9
LT
1166 n = stream->total_out - bytes;
1167 if (n > size)
1168 n = size;
1169 memcpy(buf, (char *) buffer + bytes, n);
1170 bytes = n;
456cdf6e
LT
1171 if (bytes <= size) {
1172 /*
1173 * The above condition must be (bytes <= size), not
1174 * (bytes < size). In other words, even though we
1175 * expect no more output and set avail_out to zer0,
1176 * the input zlib stream may have bytes that express
1177 * "this concludes the stream", and we *do* want to
1178 * eat that input.
1179 *
1180 * Otherwise we would not be able to test that we
1181 * consumed all the input to reach the expected size;
1182 * we also want to check that zlib tells us that all
1183 * went well with status == Z_STREAM_END at the end.
1184 */
5180cacc
LT
1185 stream->next_out = buf + bytes;
1186 stream->avail_out = size - bytes;
7efbff75 1187 while (status == Z_OK)
39c68542 1188 status = git_inflate(stream, Z_FINISH);
5180cacc 1189 }
456cdf6e 1190 if (status == Z_STREAM_END && !stream->avail_in) {
39c68542 1191 git_inflate_end(stream);
7efbff75
JH
1192 return buf;
1193 }
1194
1195 if (status < 0)
1196 error("corrupt loose object '%s'", sha1_to_hex(sha1));
1197 else if (stream->avail_in)
1198 error("garbage at end of loose object '%s'",
1199 sha1_to_hex(sha1));
1200 free(buf);
1201 return NULL;
5180cacc
LT
1202}
1203
1204/*
1205 * We used to just use "sscanf()", but that's actually way
1206 * too permissive for what we want to check. So do an anal
1207 * object header parse by hand.
1208 */
21666f1a 1209static int parse_sha1_header(const char *hdr, unsigned long *sizep)
5180cacc 1210{
21666f1a 1211 char type[10];
5180cacc
LT
1212 int i;
1213 unsigned long size;
1214
1215 /*
a6080a0a 1216 * The type can be at most ten bytes (including the
5180cacc 1217 * terminating '\0' that we add), and is followed by
21666f1a 1218 * a space.
5180cacc 1219 */
21666f1a 1220 i = 0;
5180cacc
LT
1221 for (;;) {
1222 char c = *hdr++;
1223 if (c == ' ')
1224 break;
21666f1a
NP
1225 type[i++] = c;
1226 if (i >= sizeof(type))
5180cacc 1227 return -1;
5180cacc 1228 }
21666f1a 1229 type[i] = 0;
5180cacc
LT
1230
1231 /*
1232 * The length must follow immediately, and be in canonical
1233 * decimal format (ie "010" is not valid).
1234 */
1235 size = *hdr++ - '0';
1236 if (size > 9)
1237 return -1;
1238 if (size) {
1239 for (;;) {
1240 unsigned long c = *hdr - '0';
1241 if (c > 9)
1242 break;
1243 hdr++;
1244 size = size * 10 + c;
1245 }
1246 }
1247 *sizep = size;
1248
1249 /*
1250 * The length must be followed by a zero byte
1251 */
21666f1a 1252 return *hdr ? -1 : type_from_string(type);
5180cacc
LT
1253}
1254
7efbff75 1255static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
0fcfd160 1256{
5180cacc 1257 int ret;
0fcfd160 1258 z_stream stream;
5180cacc 1259 char hdr[8192];
0fcfd160 1260
5180cacc 1261 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
21666f1a 1262 if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
0fcfd160
LT
1263 return NULL;
1264
7efbff75 1265 return unpack_sha1_rest(&stream, hdr, *size, sha1);
0fcfd160
LT
1266}
1267
54dab52a
NP
1268unsigned long get_size_from_delta(struct packed_git *p,
1269 struct pack_window **w_curs,
1270 off_t curpos)
1271{
1272 const unsigned char *data;
1273 unsigned char delta_head[20], *in;
1274 z_stream stream;
1275 int st;
1276
1277 memset(&stream, 0, sizeof(stream));
1278 stream.next_out = delta_head;
1279 stream.avail_out = sizeof(delta_head);
1280
39c68542 1281 git_inflate_init(&stream);
54dab52a
NP
1282 do {
1283 in = use_pack(p, w_curs, curpos, &stream.avail_in);
1284 stream.next_in = in;
39c68542 1285 st = git_inflate(&stream, Z_FINISH);
54dab52a
NP
1286 curpos += stream.next_in - in;
1287 } while ((st == Z_OK || st == Z_BUF_ERROR) &&
1288 stream.total_out < sizeof(delta_head));
39c68542 1289 git_inflate_end(&stream);
3d77d877
NP
1290 if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) {
1291 error("delta data unpack-initial failed");
1292 return 0;
1293 }
54dab52a
NP
1294
1295 /* Examine the initial part of the delta to figure out
1296 * the result size.
1297 */
1298 data = delta_head;
1299
1300 /* ignore base size */
1301 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1302
1303 /* Read the result size */
1304 return get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1305}
1306
c4001d92 1307static off_t get_delta_base(struct packed_git *p,
03e79c88 1308 struct pack_window **w_curs,
c4001d92 1309 off_t *curpos,
21666f1a 1310 enum object_type type,
c4001d92 1311 off_t delta_obj_offset)
eb32d236 1312{
2b87c45b 1313 unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
c4001d92 1314 off_t base_offset;
eb32d236 1315
8d8a4ea5
SP
1316 /* use_pack() assured us we have [base_info, base_info + 20)
1317 * as a range that we can look at without walking off the
1318 * end of the mapped window. Its actually the hash size
1319 * that is assured. An OFS_DELTA longer than the hash size
1320 * is stupid, as then a REF_DELTA would be smaller to store.
1321 */
21666f1a 1322 if (type == OBJ_OFS_DELTA) {
eb32d236
NP
1323 unsigned used = 0;
1324 unsigned char c = base_info[used++];
1325 base_offset = c & 127;
1326 while (c & 128) {
1327 base_offset += 1;
8723f216 1328 if (!base_offset || MSB(base_offset, 7))
8eca0b47 1329 return 0; /* overflow */
eb32d236
NP
1330 c = base_info[used++];
1331 base_offset = (base_offset << 7) + (c & 127);
1332 }
1333 base_offset = delta_obj_offset - base_offset;
d8f32556 1334 if (base_offset <= 0 || base_offset >= delta_obj_offset)
8eca0b47 1335 return 0; /* out of bound */
2b87c45b 1336 *curpos += used;
21666f1a 1337 } else if (type == OBJ_REF_DELTA) {
eb32d236
NP
1338 /* The base entry _must_ be in the same pack */
1339 base_offset = find_pack_entry_one(base_info, p);
2b87c45b 1340 *curpos += 20;
eb32d236
NP
1341 } else
1342 die("I am totally screwed");
2b87c45b 1343 return base_offset;
eb32d236
NP
1344}
1345
f3bf9224 1346/* forward declaration for a mutually recursive function */
c4001d92 1347static int packed_object_info(struct packed_git *p, off_t offset,
21666f1a 1348 unsigned long *sizep);
f3bf9224 1349
43057304 1350static int packed_delta_info(struct packed_git *p,
03e79c88 1351 struct pack_window **w_curs,
c4001d92 1352 off_t curpos,
21666f1a 1353 enum object_type type,
c4001d92 1354 off_t obj_offset,
43057304 1355 unsigned long *sizep)
5db47c2b 1356{
c4001d92 1357 off_t base_offset;
f3bf9224 1358
21666f1a 1359 base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
3d77d877
NP
1360 if (!base_offset)
1361 return OBJ_BAD;
21666f1a 1362 type = packed_object_info(p, base_offset, NULL);
3d77d877 1363 if (type <= OBJ_NONE) {
08698b1e
NP
1364 struct revindex_entry *revidx;
1365 const unsigned char *base_sha1;
1366 revidx = find_pack_revindex(p, base_offset);
1367 if (!revidx)
1368 return OBJ_BAD;
1369 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
3d77d877
NP
1370 mark_bad_packed_object(p, base_sha1);
1371 type = sha1_object_info(base_sha1, NULL);
1372 if (type <= OBJ_NONE)
1373 return OBJ_BAD;
1374 }
f3bf9224 1375
c62266f3
JH
1376 /* We choose to only get the type of the base object and
1377 * ignore potentially corrupt pack file that expects the delta
1378 * based on a base with a wrong size. This saves tons of
1379 * inflate() calls.
1380 */
3d77d877 1381 if (sizep) {
54dab52a 1382 *sizep = get_size_from_delta(p, w_curs, curpos);
3d77d877
NP
1383 if (*sizep == 0)
1384 type = OBJ_BAD;
1385 }
21666f1a
NP
1386
1387 return type;
5db47c2b
JH
1388}
1389
2b87c45b
NP
1390static int unpack_object_header(struct packed_git *p,
1391 struct pack_window **w_curs,
c4001d92 1392 off_t *curpos,
2b87c45b 1393 unsigned long *sizep)
a733cb60 1394{
03e79c88
SP
1395 unsigned char *base;
1396 unsigned int left;
ad1ed5ee 1397 unsigned long used;
2b87c45b 1398 enum object_type type;
a733cb60 1399
8d8a4ea5
SP
1400 /* use_pack() assures us we have [base, base + 20) available
1401 * as a range that we can look at at. (Its actually the hash
3dff5379 1402 * size that is assured.) With our object header encoding
8d8a4ea5
SP
1403 * the maximum deflated object size is 2^137, which is just
1404 * insane, so we know won't exceed what we have been given.
1405 */
2b87c45b 1406 base = use_pack(p, w_curs, *curpos, &left);
09ded04b
NP
1407 used = unpack_object_header_buffer(base, left, &type, sizep);
1408 if (!used) {
1409 type = OBJ_BAD;
1410 } else
1411 *curpos += used;
ad1ed5ee 1412
2b87c45b 1413 return type;
a733cb60
LT
1414}
1415
21666f1a 1416const char *packed_object_info_detail(struct packed_git *p,
c4001d92 1417 off_t obj_offset,
21666f1a
NP
1418 unsigned long *size,
1419 unsigned long *store_size,
1420 unsigned int *delta_chain_length,
1421 unsigned char *base_sha1)
ad8c80a5 1422{
03e79c88 1423 struct pack_window *w_curs = NULL;
c4001d92
SP
1424 off_t curpos;
1425 unsigned long dummy;
43057304 1426 unsigned char *next_sha1;
21666f1a 1427 enum object_type type;
70f5d5d3 1428 struct revindex_entry *revidx;
ad8c80a5 1429
43057304 1430 *delta_chain_length = 0;
2b87c45b 1431 curpos = obj_offset;
21666f1a 1432 type = unpack_object_header(p, &w_curs, &curpos, size);
43057304 1433
70f5d5d3
NP
1434 revidx = find_pack_revindex(p, obj_offset);
1435 *store_size = revidx[1].offset - obj_offset;
1436
43057304 1437 for (;;) {
21666f1a 1438 switch (type) {
43057304 1439 default:
08a19d87 1440 die("pack %s contains unknown object type %d",
21666f1a 1441 p->pack_name, type);
43057304
NP
1442 case OBJ_COMMIT:
1443 case OBJ_TREE:
1444 case OBJ_BLOB:
1445 case OBJ_TAG:
03e79c88 1446 unuse_pack(&w_curs);
21666f1a 1447 return typename(type);
eb32d236 1448 case OBJ_OFS_DELTA:
21666f1a 1449 obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
8eca0b47
NP
1450 if (!obj_offset)
1451 die("pack %s contains bad delta base reference of type %s",
1452 p->pack_name, typename(type));
eb32d236 1453 if (*delta_chain_length == 0) {
70f5d5d3
NP
1454 revidx = find_pack_revindex(p, obj_offset);
1455 hashcpy(base_sha1, nth_packed_object_sha1(p, revidx->nr));
eb32d236
NP
1456 }
1457 break;
1458 case OBJ_REF_DELTA:
2b87c45b 1459 next_sha1 = use_pack(p, &w_curs, curpos, NULL);
43057304
NP
1460 if (*delta_chain_length == 0)
1461 hashcpy(base_sha1, next_sha1);
2b87c45b 1462 obj_offset = find_pack_entry_one(next_sha1, p);
43057304
NP
1463 break;
1464 }
43057304 1465 (*delta_chain_length)++;
2b87c45b 1466 curpos = obj_offset;
21666f1a 1467 type = unpack_object_header(p, &w_curs, &curpos, &dummy);
ad8c80a5 1468 }
ad8c80a5
JH
1469}
1470
c4001d92 1471static int packed_object_info(struct packed_git *p, off_t obj_offset,
21666f1a 1472 unsigned long *sizep)
1f688557 1473{
03e79c88 1474 struct pack_window *w_curs = NULL;
c4001d92
SP
1475 unsigned long size;
1476 off_t curpos = obj_offset;
21666f1a 1477 enum object_type type;
5db47c2b 1478
21666f1a 1479 type = unpack_object_header(p, &w_curs, &curpos, &size);
5db47c2b 1480
21666f1a 1481 switch (type) {
eb32d236
NP
1482 case OBJ_OFS_DELTA:
1483 case OBJ_REF_DELTA:
21666f1a
NP
1484 type = packed_delta_info(p, &w_curs, curpos,
1485 type, obj_offset, sizep);
2b87c45b 1486 break;
a733cb60 1487 case OBJ_COMMIT:
a733cb60 1488 case OBJ_TREE:
a733cb60 1489 case OBJ_BLOB:
a733cb60 1490 case OBJ_TAG:
2b87c45b
NP
1491 if (sizep)
1492 *sizep = size;
a69d0943 1493 break;
1f688557 1494 default:
3d77d877
NP
1495 error("unknown object type %i at offset %"PRIuMAX" in %s",
1496 type, (uintmax_t)obj_offset, p->pack_name);
1497 type = OBJ_BAD;
1f688557 1498 }
2b87c45b 1499 unuse_pack(&w_curs);
21666f1a 1500 return type;
1f688557
JH
1501}
1502
eb950c19 1503static void *unpack_compressed_entry(struct packed_git *p,
03e79c88 1504 struct pack_window **w_curs,
c4001d92 1505 off_t curpos,
eb950c19 1506 unsigned long size)
de530aaa
SP
1507{
1508 int st;
1509 z_stream stream;
079afb18 1510 unsigned char *buffer, *in;
de530aaa 1511
4ab07e4d 1512 buffer = xmallocz(size);
de530aaa 1513 memset(&stream, 0, sizeof(stream));
de530aaa 1514 stream.next_out = buffer;
39eea7bd 1515 stream.avail_out = size + 1;
de530aaa 1516
39c68542 1517 git_inflate_init(&stream);
079afb18 1518 do {
2b87c45b 1519 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18 1520 stream.next_in = in;
39c68542 1521 st = git_inflate(&stream, Z_FINISH);
39eea7bd
JH
1522 if (!stream.avail_out)
1523 break; /* the payload is larger than it should be */
2b87c45b 1524 curpos += stream.next_in - in;
079afb18 1525 } while (st == Z_OK || st == Z_BUF_ERROR);
39c68542 1526 git_inflate_end(&stream);
de530aaa
SP
1527 if ((st != Z_STREAM_END) || stream.total_out != size) {
1528 free(buffer);
1529 return NULL;
1530 }
1531
1532 return buffer;
1533}
1534
e5e01619
LT
1535#define MAX_DELTA_CACHE (256)
1536
18bdec11 1537static size_t delta_base_cached;
5e08ecbf
NP
1538
1539static struct delta_base_cache_lru_list {
1540 struct delta_base_cache_lru_list *prev;
1541 struct delta_base_cache_lru_list *next;
1542} delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru };
1543
e5e01619 1544static struct delta_base_cache_entry {
5e08ecbf
NP
1545 struct delta_base_cache_lru_list lru;
1546 void *data;
e5e01619
LT
1547 struct packed_git *p;
1548 off_t base_offset;
1549 unsigned long size;
e5e01619
LT
1550 enum object_type type;
1551} delta_base_cache[MAX_DELTA_CACHE];
1552
1553static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
1554{
1555 unsigned long hash;
1556
1557 hash = (unsigned long)p + (unsigned long)base_offset;
1558 hash += (hash >> 8) + (hash >> 16);
3358004a 1559 return hash % MAX_DELTA_CACHE;
e5e01619
LT
1560}
1561
62f255ad 1562static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
a0cba108 1563 unsigned long *base_size, enum object_type *type, int keep_cache)
62f255ad 1564{
e5e01619
LT
1565 void *ret;
1566 unsigned long hash = pack_entry_hash(p, base_offset);
1567 struct delta_base_cache_entry *ent = delta_base_cache + hash;
1568
1569 ret = ent->data;
749bc58c
MV
1570 if (!ret || ent->p != p || ent->base_offset != base_offset)
1571 return unpack_entry(p, base_offset, type, base_size);
e5e01619 1572
18bdec11 1573 if (!keep_cache) {
a0cba108 1574 ent->data = NULL;
5e08ecbf
NP
1575 ent->lru.next->prev = ent->lru.prev;
1576 ent->lru.prev->next = ent->lru.next;
18bdec11 1577 delta_base_cached -= ent->size;
182af834
PH
1578 } else {
1579 ret = xmemdupz(ent->data, ent->size);
a0cba108 1580 }
e5e01619
LT
1581 *type = ent->type;
1582 *base_size = ent->size;
1583 return ret;
62f255ad
LT
1584}
1585
18bdec11
SP
1586static inline void release_delta_base_cache(struct delta_base_cache_entry *ent)
1587{
1588 if (ent->data) {
1589 free(ent->data);
1590 ent->data = NULL;
5e08ecbf
NP
1591 ent->lru.next->prev = ent->lru.prev;
1592 ent->lru.prev->next = ent->lru.next;
18bdec11
SP
1593 delta_base_cached -= ent->size;
1594 }
1595}
1596
3d20c636
SP
1597void clear_delta_base_cache(void)
1598{
1599 unsigned long p;
1600 for (p = 0; p < MAX_DELTA_CACHE; p++)
1601 release_delta_base_cache(&delta_base_cache[p]);
1602}
1603
62f255ad
LT
1604static void add_delta_base_cache(struct packed_git *p, off_t base_offset,
1605 void *base, unsigned long base_size, enum object_type type)
1606{
5e08ecbf 1607 unsigned long hash = pack_entry_hash(p, base_offset);
e5e01619 1608 struct delta_base_cache_entry *ent = delta_base_cache + hash;
5e08ecbf 1609 struct delta_base_cache_lru_list *lru;
e5e01619 1610
18bdec11
SP
1611 release_delta_base_cache(ent);
1612 delta_base_cached += base_size;
5e08ecbf
NP
1613
1614 for (lru = delta_base_cache_lru.next;
1615 delta_base_cached > delta_base_cache_limit
1616 && lru != &delta_base_cache_lru;
1617 lru = lru->next) {
1618 struct delta_base_cache_entry *f = (void *)lru;
18bdec11
SP
1619 if (f->type == OBJ_BLOB)
1620 release_delta_base_cache(f);
1621 }
5e08ecbf
NP
1622 for (lru = delta_base_cache_lru.next;
1623 delta_base_cached > delta_base_cache_limit
1624 && lru != &delta_base_cache_lru;
1625 lru = lru->next) {
1626 struct delta_base_cache_entry *f = (void *)lru;
1627 release_delta_base_cache(f);
1628 }
18bdec11 1629
e5e01619
LT
1630 ent->p = p;
1631 ent->base_offset = base_offset;
1632 ent->type = type;
1633 ent->data = base;
1634 ent->size = base_size;
5e08ecbf
NP
1635 ent->lru.next = &delta_base_cache_lru;
1636 ent->lru.prev = delta_base_cache_lru.prev;
1637 delta_base_cache_lru.prev->next = &ent->lru;
1638 delta_base_cache_lru.prev = &ent->lru;
62f255ad
LT
1639}
1640
c2c5b270
CC
1641static void *read_object(const unsigned char *sha1, enum object_type *type,
1642 unsigned long *size);
1643
eb950c19 1644static void *unpack_delta_entry(struct packed_git *p,
03e79c88 1645 struct pack_window **w_curs,
c4001d92 1646 off_t curpos,
1f688557 1647 unsigned long delta_size,
c4001d92 1648 off_t obj_offset,
21666f1a 1649 enum object_type *type,
eb950c19 1650 unsigned long *sizep)
1f688557 1651{
7c3e8be3 1652 void *delta_data, *result, *base;
c4001d92
SP
1653 unsigned long base_size;
1654 off_t base_offset;
43057304 1655
21666f1a 1656 base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
8eca0b47
NP
1657 if (!base_offset) {
1658 error("failed to validate delta base reference "
1659 "at offset %"PRIuMAX" from %s",
1660 (uintmax_t)curpos, p->pack_name);
1661 return NULL;
1662 }
eac12e2d 1663 unuse_pack(w_curs);
a0cba108 1664 base = cache_or_unpack_entry(p, base_offset, &base_size, type, 0);
8eca0b47
NP
1665 if (!base) {
1666 /*
1667 * We're probably in deep shit, but let's try to fetch
1668 * the required base anyway from another pack or loose.
1669 * This is costly but should happen only in the presence
1670 * of a corrupted pack, and is better than failing outright.
1671 */
08698b1e
NP
1672 struct revindex_entry *revidx;
1673 const unsigned char *base_sha1;
1674 revidx = find_pack_revindex(p, base_offset);
1675 if (!revidx)
1676 return NULL;
1677 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
8eca0b47
NP
1678 error("failed to read delta base object %s"
1679 " at offset %"PRIuMAX" from %s",
1680 sha1_to_hex(base_sha1), (uintmax_t)base_offset,
1681 p->pack_name);
1682 mark_bad_packed_object(p, base_sha1);
ac939109 1683 base = read_object(base_sha1, type, &base_size);
8eca0b47
NP
1684 if (!base)
1685 return NULL;
1686 }
67686d95 1687
2b87c45b 1688 delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size);
8eca0b47
NP
1689 if (!delta_data) {
1690 error("failed to unpack compressed delta "
1691 "at offset %"PRIuMAX" from %s",
1692 (uintmax_t)curpos, p->pack_name);
1693 free(base);
1694 return NULL;
1695 }
1f688557
JH
1696 result = patch_delta(base, base_size,
1697 delta_data, delta_size,
21666f1a 1698 sizep);
1f688557
JH
1699 if (!result)
1700 die("failed to apply delta");
1701 free(delta_data);
62f255ad 1702 add_delta_base_cache(p, base_offset, base, base_size, *type);
1f688557
JH
1703 return result;
1704}
1705
0e8189e2
NP
1706int do_check_packed_object_crc;
1707
c4001d92 1708void *unpack_entry(struct packed_git *p, off_t obj_offset,
21666f1a 1709 enum object_type *type, unsigned long *sizep)
1f688557 1710{
03e79c88 1711 struct pack_window *w_curs = NULL;
c4001d92 1712 off_t curpos = obj_offset;
21666f1a 1713 void *data;
1f688557 1714
0e8189e2
NP
1715 if (do_check_packed_object_crc && p->index_version > 1) {
1716 struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
1717 unsigned long len = revidx[1].offset - obj_offset;
1718 if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) {
1719 const unsigned char *sha1 =
1720 nth_packed_object_sha1(p, revidx->nr);
1721 error("bad packed object CRC for %s",
1722 sha1_to_hex(sha1));
1723 mark_bad_packed_object(p, sha1);
f755bb99 1724 unuse_pack(&w_curs);
0e8189e2
NP
1725 return NULL;
1726 }
1727 }
1728
21666f1a
NP
1729 *type = unpack_object_header(p, &w_curs, &curpos, sizep);
1730 switch (*type) {
eb32d236
NP
1731 case OBJ_OFS_DELTA:
1732 case OBJ_REF_DELTA:
21666f1a
NP
1733 data = unpack_delta_entry(p, &w_curs, curpos, *sizep,
1734 obj_offset, type, sizep);
4d703a1a 1735 break;
a733cb60 1736 case OBJ_COMMIT:
a733cb60 1737 case OBJ_TREE:
a733cb60 1738 case OBJ_BLOB:
a733cb60 1739 case OBJ_TAG:
21666f1a 1740 data = unpack_compressed_entry(p, &w_curs, curpos, *sizep);
4d703a1a 1741 break;
1f688557 1742 default:
8eca0b47
NP
1743 data = NULL;
1744 error("unknown object type %i at offset %"PRIuMAX" in %s",
1745 *type, (uintmax_t)obj_offset, p->pack_name);
1f688557 1746 }
03e79c88 1747 unuse_pack(&w_curs);
21666f1a 1748 return data;
1f688557
JH
1749}
1750
d079837e 1751const unsigned char *nth_packed_object_sha1(struct packed_git *p,
d72308e0 1752 uint32_t n)
9a217f2a 1753{
42873078 1754 const unsigned char *index = p->index_data;
d079837e
SP
1755 if (!index) {
1756 if (open_pack_index(p))
1757 return NULL;
1758 index = p->index_data;
1759 }
57059091 1760 if (n >= p->num_objects)
d72308e0 1761 return NULL;
74e34e1f
NP
1762 index += 4 * 256;
1763 if (p->index_version == 1) {
1764 return index + 24 * n + 4;
1765 } else {
1766 index += 8;
1767 return index + 20 * n;
1768 }
1769}
1770
99093238 1771off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
74e34e1f
NP
1772{
1773 const unsigned char *index = p->index_data;
1774 index += 4 * 256;
1775 if (p->index_version == 1) {
1776 return ntohl(*((uint32_t *)(index + 24 * n)));
1777 } else {
1778 uint32_t off;
1779 index += 8 + p->num_objects * (20 + 4);
1780 off = ntohl(*((uint32_t *)(index + 4 * n)));
1781 if (!(off & 0x80000000))
1782 return off;
1783 index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
1784 return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
1785 ntohl(*((uint32_t *)(index + 4)));
1786 }
9a217f2a
JH
1787}
1788
c4001d92 1789off_t find_pack_entry_one(const unsigned char *sha1,
43057304 1790 struct packed_git *p)
1f688557 1791{
42873078 1792 const uint32_t *level1_ofs = p->index_data;
42873078 1793 const unsigned char *index = p->index_data;
628522ec
JH
1794 unsigned hi, lo, stride;
1795 static int use_lookup = -1;
1796 static int debug_lookup = -1;
1797
1798 if (debug_lookup < 0)
1799 debug_lookup = !!getenv("GIT_DEBUG_LOOKUP");
42873078 1800
d079837e
SP
1801 if (!index) {
1802 if (open_pack_index(p))
1803 return 0;
1804 level1_ofs = p->index_data;
1805 index = p->index_data;
1806 }
74e34e1f
NP
1807 if (p->index_version > 1) {
1808 level1_ofs += 2;
1809 index += 8;
1810 }
42873078 1811 index += 4 * 256;
74e34e1f
NP
1812 hi = ntohl(level1_ofs[*sha1]);
1813 lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
628522ec
JH
1814 if (p->index_version > 1) {
1815 stride = 20;
1816 } else {
1817 stride = 24;
1818 index += 4;
1819 }
1820
1821 if (debug_lookup)
6e1c2344 1822 printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n",
628522ec
JH
1823 sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects);
1824
1825 if (use_lookup < 0)
1826 use_lookup = !!getenv("GIT_USE_LOOKUP");
1827 if (use_lookup) {
1828 int pos = sha1_entry_pos(index, stride, 0,
1829 lo, hi, p->num_objects, sha1);
1830 if (pos < 0)
1831 return 0;
1832 return nth_packed_object_offset(p, pos);
1833 }
1f688557
JH
1834
1835 do {
74e34e1f 1836 unsigned mi = (lo + hi) / 2;
628522ec
JH
1837 int cmp = hashcmp(index + mi * stride, sha1);
1838
1839 if (debug_lookup)
1840 printf("lo %u hi %u rg %u mi %u\n",
1841 lo, hi, hi - lo, mi);
43057304 1842 if (!cmp)
74e34e1f 1843 return nth_packed_object_offset(p, mi);
1f688557
JH
1844 if (cmp > 0)
1845 hi = mi;
1846 else
1847 lo = mi+1;
1848 } while (lo < hi);
1849 return 0;
1850}
1851
4d6acb70 1852static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1f688557 1853{
f7c22cc6 1854 static struct packed_git *last_found = (void *)1;
1f688557 1855 struct packed_git *p;
c4001d92 1856 off_t offset;
43057304 1857
1f688557 1858 prepare_packed_git();
f7c22cc6
NP
1859 if (!packed_git)
1860 return 0;
1861 p = (last_found == (void *)1) ? packed_git : last_found;
1f688557 1862
f7c22cc6 1863 do {
8eca0b47
NP
1864 if (p->num_bad_objects) {
1865 unsigned i;
1866 for (i = 0; i < p->num_bad_objects; i++)
1867 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1868 goto next;
1869 }
1870
43057304
NP
1871 offset = find_pack_entry_one(sha1, p);
1872 if (offset) {
c715f783
SP
1873 /*
1874 * We are about to tell the caller where they can
1875 * locate the requested object. We better make
1876 * sure the packfile is still here and can be
1877 * accessed before supplying that answer, as
1878 * it may have been deleted since the index
1879 * was loaded!
1880 */
1881 if (p->pack_fd == -1 && open_packed_git(p)) {
1882 error("packfile %s cannot be accessed", p->pack_name);
f7c22cc6 1883 goto next;
c715f783 1884 }
43057304
NP
1885 e->offset = offset;
1886 e->p = p;
1887 hashcpy(e->sha1, sha1);
f7c22cc6 1888 last_found = p;
1f688557 1889 return 1;
43057304 1890 }
f7c22cc6
NP
1891
1892 next:
1893 if (p == last_found)
1894 p = packed_git;
1895 else
1896 p = p->next;
1897 if (p == last_found)
1898 p = p->next;
1899 } while (p);
1f688557
JH
1900 return 0;
1901}
1902
a6080a0a 1903struct packed_git *find_sha1_pack(const unsigned char *sha1,
bf592c50
DB
1904 struct packed_git *packs)
1905{
1906 struct packed_git *p;
bf592c50
DB
1907
1908 for (p = packs; p; p = p->next) {
43057304 1909 if (find_pack_entry_one(sha1, p))
bf592c50
DB
1910 return p;
1911 }
1912 return NULL;
21666f1a 1913
bf592c50
DB
1914}
1915
21666f1a 1916static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep)
65c2e0c3 1917{
36e4d74a 1918 int status;
65c2e0c3
JH
1919 unsigned long mapsize, size;
1920 void *map;
1921 z_stream stream;
d65a16f6 1922 char hdr[32];
65c2e0c3 1923
bb6b8e4f 1924 map = map_sha1_file(sha1, &mapsize);
f0df4ed5
JS
1925 if (!map)
1926 return error("unable to find %s", sha1_to_hex(sha1));
36e4d74a
JH
1927 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1928 status = error("unable to unpack %s header",
1929 sha1_to_hex(sha1));
21666f1a 1930 else if ((status = parse_sha1_header(hdr, &size)) < 0)
36e4d74a 1931 status = error("unable to parse %s header", sha1_to_hex(sha1));
21666f1a
NP
1932 else if (sizep)
1933 *sizep = size;
39c68542 1934 git_inflate_end(&stream);
65c2e0c3
JH
1935 munmap(map, mapsize);
1936 return status;
1937}
1938
21666f1a 1939int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
f0df4ed5 1940{
f0df4ed5 1941 struct pack_entry e;
ddd63e64 1942 int status;
f0df4ed5 1943
cd673c1f 1944 if (!find_pack_entry(sha1, &e)) {
ddd63e64
SG
1945 /* Most likely it's a loose object. */
1946 status = sha1_loose_object_info(sha1, sizep);
1947 if (status >= 0)
1948 return status;
1949
1950 /* Not a loose object; someone else may have just packed it. */
f0df4ed5 1951 reprepare_packed_git();
cd673c1f 1952 if (!find_pack_entry(sha1, &e))
ddd63e64 1953 return status;
f0df4ed5 1954 }
3d77d877
NP
1955
1956 status = packed_object_info(e.p, e.offset, sizep);
1957 if (status < 0) {
1958 mark_bad_packed_object(e.p, sha1);
1959 status = sha1_object_info(sha1, sizep);
1960 }
1961
1962 return status;
f0df4ed5
JS
1963}
1964
21666f1a
NP
1965static void *read_packed_sha1(const unsigned char *sha1,
1966 enum object_type *type, unsigned long *size)
1f688557
JH
1967{
1968 struct pack_entry e;
8eca0b47 1969 void *data;
1f688557 1970
cd673c1f 1971 if (!find_pack_entry(sha1, &e))
1f688557 1972 return NULL;
8eca0b47
NP
1973 data = cache_or_unpack_entry(e.p, e.offset, size, type, 1);
1974 if (!data) {
1975 /*
1976 * We're probably in deep shit, but let's try to fetch
1977 * the required object anyway from another pack or loose.
1978 * This should happen only in the presence of a corrupted
1979 * pack, and is better than failing outright.
1980 */
1981 error("failed to read object %s at offset %"PRIuMAX" from %s",
1982 sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name);
1983 mark_bad_packed_object(e.p, sha1);
ac939109 1984 data = read_object(sha1, type, size);
8eca0b47
NP
1985 }
1986 return data;
1f688557
JH
1987}
1988
d66b37bb
JH
1989/*
1990 * This is meant to hold a *small* number of objects that you would
1991 * want read_sha1_file() to be able to return, but yet you do not want
1992 * to write them into the object store (e.g. a browse-only
1993 * application).
1994 */
1995static struct cached_object {
1996 unsigned char sha1[20];
21666f1a 1997 enum object_type type;
d66b37bb
JH
1998 void *buf;
1999 unsigned long size;
2000} *cached_objects;
2001static int cached_object_nr, cached_object_alloc;
2002
346245a1 2003static struct cached_object empty_tree = {
14d9c578 2004 EMPTY_TREE_SHA1_BIN,
346245a1
JK
2005 OBJ_TREE,
2006 "",
2007 0
2008};
2009
d66b37bb
JH
2010static struct cached_object *find_cached_object(const unsigned char *sha1)
2011{
2012 int i;
2013 struct cached_object *co = cached_objects;
2014
2015 for (i = 0; i < cached_object_nr; i++, co++) {
2016 if (!hashcmp(co->sha1, sha1))
2017 return co;
2018 }
346245a1
JK
2019 if (!hashcmp(sha1, empty_tree.sha1))
2020 return &empty_tree;
d66b37bb
JH
2021 return NULL;
2022}
2023
21666f1a
NP
2024int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
2025 unsigned char *sha1)
d66b37bb
JH
2026{
2027 struct cached_object *co;
2028
21666f1a 2029 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
2030 if (has_sha1_file(sha1) || find_cached_object(sha1))
2031 return 0;
2032 if (cached_object_alloc <= cached_object_nr) {
2033 cached_object_alloc = alloc_nr(cached_object_alloc);
2034 cached_objects = xrealloc(cached_objects,
2035 sizeof(*cached_objects) *
2036 cached_object_alloc);
2037 }
2038 co = &cached_objects[cached_object_nr++];
2039 co->size = len;
21666f1a 2040 co->type = type;
efa13f7b
JH
2041 co->buf = xmalloc(len);
2042 memcpy(co->buf, buf, len);
d66b37bb
JH
2043 hashcpy(co->sha1, sha1);
2044 return 0;
2045}
2046
c2c5b270
CC
2047static void *read_object(const unsigned char *sha1, enum object_type *type,
2048 unsigned long *size)
0fcfd160
LT
2049{
2050 unsigned long mapsize;
2051 void *map, *buf;
d66b37bb
JH
2052 struct cached_object *co;
2053
2054 co = find_cached_object(sha1);
2055 if (co) {
21666f1a 2056 *type = co->type;
d66b37bb 2057 *size = co->size;
182af834 2058 return xmemdupz(co->buf, co->size);
d66b37bb 2059 }
0fcfd160 2060
8276c007
PE
2061 buf = read_packed_sha1(sha1, type, size);
2062 if (buf)
2063 return buf;
bb6b8e4f 2064 map = map_sha1_file(sha1, &mapsize);
0fcfd160 2065 if (map) {
7efbff75 2066 buf = unpack_sha1_file(map, mapsize, type, size, sha1);
0fcfd160
LT
2067 munmap(map, mapsize);
2068 return buf;
2069 }
637cdd9d 2070 reprepare_packed_git();
8276c007 2071 return read_packed_sha1(sha1, type, size);
0fcfd160
LT
2072}
2073
f5552aee
CC
2074void *read_sha1_file_repl(const unsigned char *sha1,
2075 enum object_type *type,
2076 unsigned long *size,
2077 const unsigned char **replacement)
ac939109 2078{
68095570
CC
2079 const unsigned char *repl = lookup_replace_object(sha1);
2080 void *data = read_object(repl, type, size);
2081
2082 /* die if we replaced an object with one that does not exist */
2083 if (!data && repl != sha1)
2084 die("replacement %s not found for %s",
2085 sha1_to_hex(repl), sha1_to_hex(sha1));
2086
ac939109 2087 /* legacy behavior is to die on corrupted objects */
68095570
CC
2088 if (!data && (has_loose_object(repl) || has_packed_and_bad(repl)))
2089 die("object %s is corrupted", sha1_to_hex(repl));
2090
f5552aee
CC
2091 if (replacement)
2092 *replacement = repl;
2093
ac939109
NP
2094 return data;
2095}
2096
40469ee9 2097void *read_object_with_reference(const unsigned char *sha1,
21666f1a 2098 const char *required_type_name,
40469ee9
JH
2099 unsigned long *size,
2100 unsigned char *actual_sha1_return)
f4913f91 2101{
21666f1a 2102 enum object_type type, required_type;
f4913f91
JH
2103 void *buffer;
2104 unsigned long isize;
40469ee9 2105 unsigned char actual_sha1[20];
f4913f91 2106
21666f1a 2107 required_type = type_from_string(required_type_name);
e702496e 2108 hashcpy(actual_sha1, sha1);
40469ee9
JH
2109 while (1) {
2110 int ref_length = -1;
2111 const char *ref_type = NULL;
f4913f91 2112
21666f1a 2113 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
2114 if (!buffer)
2115 return NULL;
21666f1a 2116 if (type == required_type) {
40469ee9
JH
2117 *size = isize;
2118 if (actual_sha1_return)
e702496e 2119 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
2120 return buffer;
2121 }
2122 /* Handle references */
21666f1a 2123 else if (type == OBJ_COMMIT)
40469ee9 2124 ref_type = "tree ";
21666f1a 2125 else if (type == OBJ_TAG)
40469ee9
JH
2126 ref_type = "object ";
2127 else {
2128 free(buffer);
2129 return NULL;
2130 }
2131 ref_length = strlen(ref_type);
f4913f91 2132
50974ec9
MK
2133 if (ref_length + 40 > isize ||
2134 memcmp(buffer, ref_type, ref_length) ||
1d7f171c 2135 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
2136 free(buffer);
2137 return NULL;
2138 }
1cf58e72 2139 free(buffer);
40469ee9
JH
2140 /* Now we have the ID of the referred-to object in
2141 * actual_sha1. Check again. */
f4913f91 2142 }
f4913f91
JH
2143}
2144
ce9fbf16 2145static void write_sha1_file_prepare(const void *buf, unsigned long len,
972a9155 2146 const char *type, unsigned char *sha1,
d65a16f6 2147 char *hdr, int *hdrlen)
d410c0f5 2148{
9126f009 2149 git_SHA_CTX c;
d410c0f5
JH
2150
2151 /* Generate the header */
d65a16f6 2152 *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
d410c0f5
JH
2153
2154 /* Sha1.. */
9126f009
NP
2155 git_SHA1_Init(&c);
2156 git_SHA1_Update(&c, hdr, *hdrlen);
2157 git_SHA1_Update(&c, buf, len);
2158 git_SHA1_Final(sha1, &c);
d410c0f5
JH
2159}
2160
230f1322 2161/*
5a688fe4
JH
2162 * Move the just written object into its final resting place.
2163 * NEEDSWORK: this should be renamed to finalize_temp_file() as
2164 * "moving" is only a part of what it does, when no patch between
2165 * master to pu changes the call sites of this function.
230f1322 2166 */
839837b9 2167int move_temp_to_file(const char *tmpfile, const char *filename)
230f1322 2168{
e32c0a9c 2169 int ret = 0;
5a688fe4 2170
348df166 2171 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
be66a6c4
JS
2172 goto try_rename;
2173 else if (link(tmpfile, filename))
e32c0a9c 2174 ret = errno;
7ebb6fca
LT
2175
2176 /*
2177 * Coda hack - coda doesn't like cross-directory links,
2178 * so we fall back to a rename, which will mean that it
2179 * won't be able to check collisions, but that's not a
2180 * big deal.
2181 *
2182 * The same holds for FAT formatted media.
2183 *
3be1f18e 2184 * When this succeeds, we just return. We have nothing
7ebb6fca
LT
2185 * left to unlink.
2186 */
2187 if (ret && ret != EEXIST) {
be66a6c4 2188 try_rename:
7ebb6fca 2189 if (!rename(tmpfile, filename))
3be1f18e 2190 goto out;
9e48b389 2191 ret = errno;
230f1322 2192 }
691f1a28 2193 unlink_or_warn(tmpfile);
230f1322
LT
2194 if (ret) {
2195 if (ret != EEXIST) {
916d081b 2196 return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret));
230f1322
LT
2197 }
2198 /* FIXME!!! Collision check here ? */
2199 }
2200
3be1f18e 2201out:
5256b006 2202 if (adjust_shared_perm(filename))
5a688fe4 2203 return error("unable to set permission to '%s'", filename);
230f1322
LT
2204 return 0;
2205}
2206
4d548150
LT
2207static int write_buffer(int fd, const void *buf, size_t len)
2208{
d34cf19b 2209 if (write_in_full(fd, buf, len) < 0)
93822c22 2210 return error("file write error (%s)", strerror(errno));
4d548150
LT
2211 return 0;
2212}
2213
ce9fbf16 2214int hash_sha1_file(const void *buf, unsigned long len, const char *type,
abdc3fc8
RS
2215 unsigned char *sha1)
2216{
d65a16f6 2217 char hdr[32];
abdc3fc8
RS
2218 int hdrlen;
2219 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2220 return 0;
2221}
2222
e9039dd3
LT
2223/* Finalize a file on disk, and close it. */
2224static void close_sha1_file(int fd)
2225{
aafe9fba
LT
2226 if (fsync_object_files)
2227 fsync_or_die(fd, "sha1 file");
e9039dd3 2228 if (close(fd) != 0)
d824cbba 2229 die_errno("error when closing sha1 file");
e9039dd3
LT
2230}
2231
5723fe7e
LT
2232/* Size of directory component, including the ending '/' */
2233static inline int directory_size(const char *filename)
2234{
2235 const char *s = strrchr(filename, '/');
2236 if (!s)
2237 return 0;
2238 return s - filename + 1;
2239}
2240
2241/*
2242 * This creates a temporary file in the same directory as the final
2243 * 'filename'
2244 *
2245 * We want to avoid cross-directory filename renames, because those
2246 * can have problems on various filesystems (FAT, NFS, Coda).
2247 */
2248static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename)
2249{
2250 int fd, dirlen = directory_size(filename);
2251
2252 if (dirlen + 20 > bufsiz) {
2253 errno = ENAMETOOLONG;
2254 return -1;
2255 }
2256 memcpy(buffer, filename, dirlen);
2257 strcpy(buffer + dirlen, "tmp_obj_XXXXXX");
5256b006 2258 fd = git_mkstemp_mode(buffer, 0444);
cbacbf4e 2259 if (fd < 0 && dirlen && errno == ENOENT) {
5723fe7e 2260 /* Make sure the directory exists */
6ff6af62 2261 memcpy(buffer, filename, dirlen);
5723fe7e 2262 buffer[dirlen-1] = 0;
3bfaf018 2263 if (mkdir(buffer, 0777) || adjust_shared_perm(buffer))
5723fe7e
LT
2264 return -1;
2265
2266 /* Try again */
2267 strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX");
5256b006 2268 fd = git_mkstemp_mode(buffer, 0444);
5723fe7e
LT
2269 }
2270 return fd;
2271}
2272
bbac7311
NP
2273static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
2274 void *buf, unsigned long len, time_t mtime)
0fcfd160 2275{
915308b1 2276 int fd, ret;
9892beba 2277 unsigned char compressed[4096];
0fcfd160 2278 z_stream stream;
748af44c
NP
2279 git_SHA_CTX c;
2280 unsigned char parano_sha1[20];
706bc531 2281 char *filename;
aac17941 2282 static char tmpfile[PATH_MAX];
a44c9a5e 2283
972a9155 2284 filename = sha1_file_name(sha1);
5723fe7e 2285 fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename);
fd73ccf2
JS
2286 while (fd < 0 && errno == EMFILE && unuse_one_window(packed_git, -1))
2287 fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename);
aac17941 2288 if (fd < 0) {
35243577 2289 if (errno == EACCES)
916d081b
PB
2290 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
2291 else
2292 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
aac17941
LT
2293 }
2294
0fcfd160
LT
2295 /* Set it up */
2296 memset(&stream, 0, sizeof(stream));
12f6c308 2297 deflateInit(&stream, zlib_compression_level);
0fcfd160 2298 stream.next_out = compressed;
9892beba 2299 stream.avail_out = sizeof(compressed);
748af44c 2300 git_SHA1_Init(&c);
a44c9a5e
LT
2301
2302 /* First header.. */
d65a16f6 2303 stream.next_in = (unsigned char *)hdr;
a44c9a5e 2304 stream.avail_in = hdrlen;
726f852b
NP
2305 while (deflate(&stream, 0) == Z_OK)
2306 /* nothing */;
748af44c 2307 git_SHA1_Update(&c, hdr, hdrlen);
a44c9a5e
LT
2308
2309 /* Then the data itself.. */
2310 stream.next_in = buf;
2311 stream.avail_in = len;
9892beba 2312 do {
748af44c 2313 unsigned char *in0 = stream.next_in;
9892beba 2314 ret = deflate(&stream, Z_FINISH);
748af44c 2315 git_SHA1_Update(&c, in0, stream.next_in - in0);
9892beba
NP
2316 if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
2317 die("unable to write sha1 file");
2318 stream.next_out = compressed;
2319 stream.avail_out = sizeof(compressed);
2320 } while (ret == Z_OK);
2321
ac54c277
LT
2322 if (ret != Z_STREAM_END)
2323 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
ac54c277
LT
2324 ret = deflateEnd(&stream);
2325 if (ret != Z_OK)
2326 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
748af44c
NP
2327 git_SHA1_Final(parano_sha1, &c);
2328 if (hashcmp(sha1, parano_sha1) != 0)
2329 die("confused by unstable object source data for %s", sha1_to_hex(sha1));
ac54c277 2330
e9039dd3 2331 close_sha1_file(fd);
0fcfd160 2332
bbac7311
NP
2333 if (mtime) {
2334 struct utimbuf utb;
2335 utb.actime = mtime;
2336 utb.modtime = mtime;
2337 if (utime(tmpfile, &utb) < 0)
2338 warning("failed utime() on %s: %s",
2339 tmpfile, strerror(errno));
2340 }
2341
230f1322 2342 return move_temp_to_file(tmpfile, filename);
0fcfd160 2343}
8237b185 2344
bbac7311
NP
2345int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
2346{
2347 unsigned char sha1[20];
2348 char hdr[32];
2349 int hdrlen;
2350
2351 /* Normally if we have it in the pack then we do not bother writing
2352 * it out into .git/objects/??/?{38} file.
2353 */
2354 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2355 if (returnsha1)
2356 hashcpy(returnsha1, sha1);
2357 if (has_sha1_file(sha1))
2358 return 0;
2359 return write_loose_object(sha1, hdr, hdrlen, buf, len, 0);
2360}
2361
2362int force_object_loose(const unsigned char *sha1, time_t mtime)
2363{
bbac7311
NP
2364 void *buf;
2365 unsigned long len;
2366 enum object_type type;
2367 char hdr[32];
2368 int hdrlen;
1fb23e65 2369 int ret;
bbac7311 2370
c529d75a 2371 if (has_loose_object(sha1))
bbac7311
NP
2372 return 0;
2373 buf = read_packed_sha1(sha1, &type, &len);
2374 if (!buf)
2375 return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
2376 hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
1fb23e65
BS
2377 ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
2378 free(buf);
2379
2380 return ret;
bbac7311
NP
2381}
2382
bf592c50
DB
2383int has_pack_index(const unsigned char *sha1)
2384{
2385 struct stat st;
2386 if (stat(sha1_pack_index_name(sha1), &st))
2387 return 0;
2388 return 1;
bf592c50
DB
2389}
2390
cd673c1f
JH
2391int has_sha1_pack(const unsigned char *sha1)
2392{
2393 struct pack_entry e;
2394 return find_pack_entry(sha1, &e);
2395}
2396
8237b185
DB
2397int has_sha1_file(const unsigned char *sha1)
2398{
1f688557
JH
2399 struct pack_entry e;
2400
cd673c1f 2401 if (find_pack_entry(sha1, &e))
1f688557 2402 return 1;
c529d75a 2403 return has_loose_object(sha1);
8237b185 2404}
74400e71 2405
43df4f86
DP
2406static int index_mem(unsigned char *sha1, void *buf, size_t size,
2407 int write_object, enum object_type type, const char *path)
e7332f96 2408{
6c510bee 2409 int ret, re_allocated = 0;
74400e71 2410
7672db20 2411 if (!type)
edaec3fb 2412 type = OBJ_BLOB;
6c510bee
LT
2413
2414 /*
2415 * Convert blobs to git internal format
2416 */
43df4f86 2417 if ((type == OBJ_BLOB) && path) {
f285a2d7 2418 struct strbuf nbuf = STRBUF_INIT;
21e5ad50
SP
2419 if (convert_to_git(path, buf, size, &nbuf,
2420 write_object ? safe_crlf : 0)) {
b315c5c0 2421 buf = strbuf_detach(&nbuf, &size);
6c510bee
LT
2422 re_allocated = 1;
2423 }
2424 }
2425
7672db20 2426 if (write_object)
edaec3fb 2427 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 2428 else
edaec3fb 2429 ret = hash_sha1_file(buf, size, typename(type), sha1);
43df4f86 2430 if (re_allocated)
6c510bee 2431 free(buf);
43df4f86
DP
2432 return ret;
2433}
2434
ea68b0ce
DP
2435#define SMALL_FILE_SIZE (32*1024)
2436
43df4f86
DP
2437int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object,
2438 enum object_type type, const char *path)
2439{
2440 int ret;
2441 size_t size = xsize_t(st->st_size);
2442
2443 if (!S_ISREG(st->st_mode)) {
f285a2d7 2444 struct strbuf sbuf = STRBUF_INIT;
43df4f86
DP
2445 if (strbuf_read(&sbuf, fd, 4096) >= 0)
2446 ret = index_mem(sha1, sbuf.buf, sbuf.len, write_object,
2447 type, path);
2448 else
2449 ret = -1;
2450 strbuf_release(&sbuf);
ea68b0ce
DP
2451 } else if (size <= SMALL_FILE_SIZE) {
2452 char *buf = xmalloc(size);
2453 if (size == read_in_full(fd, buf, size))
2454 ret = index_mem(sha1, buf, size, write_object, type,
2455 path);
2456 else
2457 ret = error("short read %s", strerror(errno));
2458 free(buf);
43df4f86
DP
2459 } else if (size) {
2460 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
2461 ret = index_mem(sha1, buf, size, write_object, type, path);
aac17941 2462 munmap(buf, size);
43df4f86
DP
2463 } else
2464 ret = index_mem(sha1, NULL, size, write_object, type, path);
2465 close(fd);
aac17941 2466 return ret;
74400e71 2467}
ec1fcc16
JH
2468
2469int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
2470{
2471 int fd;
b760d3aa 2472 struct strbuf sb = STRBUF_INIT;
ec1fcc16
JH
2473
2474 switch (st->st_mode & S_IFMT) {
2475 case S_IFREG:
2476 fd = open(path, O_RDONLY);
2477 if (fd < 0)
2478 return error("open(\"%s\"): %s", path,
2479 strerror(errno));
53bca91a 2480 if (index_fd(sha1, fd, st, write_object, OBJ_BLOB, path) < 0)
ec1fcc16
JH
2481 return error("%s: failed to insert into database",
2482 path);
2483 break;
2484 case S_IFLNK:
b760d3aa 2485 if (strbuf_readlink(&sb, path, st->st_size)) {
ec1fcc16 2486 char *errstr = strerror(errno);
ec1fcc16
JH
2487 return error("readlink(\"%s\"): %s", path,
2488 errstr);
2489 }
abdc3fc8 2490 if (!write_object)
b760d3aa
LT
2491 hash_sha1_file(sb.buf, sb.len, blob_type, sha1);
2492 else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1))
ec1fcc16
JH
2493 return error("%s: failed to insert into database",
2494 path);
b760d3aa 2495 strbuf_release(&sb);
ec1fcc16 2496 break;
f35a6d3b
LT
2497 case S_IFDIR:
2498 return resolve_gitlink_ref(path, "HEAD", sha1);
ec1fcc16
JH
2499 default:
2500 return error("%s: unsupported file type", path);
2501 }
2502 return 0;
2503}
a69e5429
JH
2504
2505int read_pack_header(int fd, struct pack_header *header)
2506{
c697ad14
HO
2507 if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header))
2508 /* "eof before pack header was fully read" */
2509 return PH_ERROR_EOF;
2510
a69e5429
JH
2511 if (header->hdr_signature != htonl(PACK_SIGNATURE))
2512 /* "protocol error (pack signature mismatch detected)" */
2513 return PH_ERROR_PACK_SIGNATURE;
2514 if (!pack_version_ok(header->hdr_version))
2515 /* "protocol error (pack version unsupported)" */
2516 return PH_ERROR_PROTOCOL;
2517 return 0;
2518}