zlib: wrap deflateBound() too
[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"
c879daa2 16#include "tree-walk.h"
f35a6d3b 17#include "refs.h"
70f5d5d3 18#include "pack-revindex.h"
628522ec 19#include "sha1-lookup.h"
0fcfd160 20
144bde78
LT
21#ifndef O_NOATIME
22#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
23#define O_NOATIME 01000000
24#else
25#define O_NOATIME 0
26#endif
27#endif
28
28bd70d8
JN
29#define SZ_FMT PRIuMAX
30static inline uintmax_t sz_fmt(size_t s) { return s; }
e05db0fd 31
96f1e58f 32const unsigned char null_sha1[20];
88cd621d 33
c597ba80
NTND
34/*
35 * This is meant to hold a *small* number of objects that you would
36 * want read_sha1_file() to be able to return, but yet you do not want
37 * to write them into the object store (e.g. a browse-only
38 * application).
39 */
40static struct cached_object {
41 unsigned char sha1[20];
42 enum object_type type;
43 void *buf;
44 unsigned long size;
45} *cached_objects;
46static int cached_object_nr, cached_object_alloc;
47
48static struct cached_object empty_tree = {
dab0d410 49 EMPTY_TREE_SHA1_BIN_LITERAL,
c597ba80
NTND
50 OBJ_TREE,
51 "",
52 0
53};
54
55static struct cached_object *find_cached_object(const unsigned char *sha1)
56{
57 int i;
58 struct cached_object *co = cached_objects;
59
60 for (i = 0; i < cached_object_nr; i++, co++) {
61 if (!hashcmp(co->sha1, sha1))
62 return co;
63 }
64 if (!hashcmp(sha1, empty_tree.sha1))
65 return &empty_tree;
66 return NULL;
67}
68
90a6464b
JH
69int mkdir_in_gitdir(const char *path)
70{
71 if (mkdir(path, 0777)) {
72 int saved_errno = errno;
73 struct stat st;
74 struct strbuf sb = STRBUF_INIT;
75
76 if (errno != EEXIST)
77 return -1;
78 /*
79 * Are we looking at a path in a symlinked worktree
80 * whose original repository does not yet have it?
81 * e.g. .git/rr-cache pointing at its original
82 * repository in which the user hasn't performed any
83 * conflict resolution yet?
84 */
85 if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
86 strbuf_readlink(&sb, path, st.st_size) ||
87 !is_absolute_path(sb.buf) ||
88 mkdir(sb.buf, 0777)) {
89 strbuf_release(&sb);
90 errno = saved_errno;
91 return -1;
92 }
93 strbuf_release(&sb);
94 }
95 return adjust_shared_perm(path);
96}
97
b2cb9425
JH
98int safe_create_leading_directories(char *path)
99{
8385abfd 100 char *pos = path + offset_1st_component(path);
67d42212
JR
101 struct stat st;
102
b2cb9425
JH
103 while (pos) {
104 pos = strchr(pos, '/');
105 if (!pos)
106 break;
5f0bdf50
JH
107 while (*++pos == '/')
108 ;
109 if (!*pos)
110 break;
111 *--pos = '\0';
67d42212
JR
112 if (!stat(path, &st)) {
113 /* path exists */
114 if (!S_ISDIR(st.st_mode)) {
b2cb9425 115 *pos = '/';
67d42212 116 return -3;
b2cb9425 117 }
457f06d6 118 }
67d42212
JR
119 else if (mkdir(path, 0777)) {
120 *pos = '/';
121 return -1;
122 }
457f06d6
JS
123 else if (adjust_shared_perm(path)) {
124 *pos = '/';
125 return -2;
126 }
b2cb9425
JH
127 *pos++ = '/';
128 }
129 return 0;
130}
723c31fe 131
8e21d63b
JK
132int safe_create_leading_directories_const(const char *path)
133{
134 /* path points to cache entries, so xstrdup before messing with it */
135 char *buf = xstrdup(path);
136 int result = safe_create_leading_directories(buf);
137 free(buf);
138 return result;
139}
140
ace1534d
JH
141static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
142{
143 int i;
144 for (i = 0; i < 20; i++) {
145 static char hex[] = "0123456789abcdef";
146 unsigned int val = sha1[i];
147 char *pos = pathbuf + i*2 + (i > 0);
148 *pos++ = hex[val >> 4];
149 *pos = hex[val & 0xf];
150 }
151}
152
0fcfd160
LT
153/*
154 * NOTE! This returns a statically allocated buffer, so you have to be
790296fd 155 * careful about using it. Do an "xstrdup()" if you need to save the
0fcfd160 156 * filename.
ace1534d
JH
157 *
158 * Also note that this returns the location for creating. Reading
159 * SHA1 file can happen from any alternate directory listed in the
d19938ab 160 * DB_ENVIRONMENT environment variable if it is not found in
ace1534d 161 * the primary object database.
0fcfd160
LT
162 */
163char *sha1_file_name(const unsigned char *sha1)
164{
560fb6a1
JK
165 static char buf[PATH_MAX];
166 const char *objdir;
167 int len;
0fcfd160 168
560fb6a1
JK
169 objdir = get_object_directory();
170 len = strlen(objdir);
171
172 /* '/' + sha1(2) + '/' + sha1(38) + '\0' */
173 if (len + 43 > PATH_MAX)
174 die("insanely long object directory %s", objdir);
175 memcpy(buf, objdir, len);
176 buf[len] = '/';
177 buf[len+3] = '/';
178 buf[len+42] = '\0';
179 fill_sha1_path(buf + len + 1, sha1);
180 return buf;
0fcfd160
LT
181}
182
633f43e1 183static char *sha1_get_pack_name(const unsigned char *sha1,
6eec46bd 184 char **name, char **base, const char *which)
bf592c50
DB
185{
186 static const char hex[] = "0123456789abcdef";
633f43e1 187 char *buf;
bf592c50
DB
188 int i;
189
633f43e1 190 if (!*base) {
bf592c50
DB
191 const char *sha1_file_directory = get_object_directory();
192 int len = strlen(sha1_file_directory);
633f43e1 193 *base = xmalloc(len + 60);
6eec46bd
JH
194 sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
195 sha1_file_directory, which);
633f43e1 196 *name = *base + len + 11;
bf592c50
DB
197 }
198
633f43e1 199 buf = *name;
bf592c50
DB
200
201 for (i = 0; i < 20; i++) {
202 unsigned int val = *sha1++;
203 *buf++ = hex[val >> 4];
204 *buf++ = hex[val & 0xf];
205 }
a6080a0a 206
633f43e1 207 return *base;
bf592c50
DB
208}
209
633f43e1 210char *sha1_pack_name(const unsigned char *sha1)
bf592c50 211{
633f43e1 212 static char *name, *base;
bf592c50 213
6eec46bd 214 return sha1_get_pack_name(sha1, &name, &base, "pack");
633f43e1 215}
bf592c50 216
633f43e1
HO
217char *sha1_pack_index_name(const unsigned char *sha1)
218{
219 static char *name, *base;
a6080a0a 220
6eec46bd 221 return sha1_get_pack_name(sha1, &name, &base, "idx");
bf592c50
DB
222}
223
d5a63b99
JH
224struct alternate_object_database *alt_odb_list;
225static struct alternate_object_database **alt_odb_tail;
ace1534d 226
c2f493a4 227static void read_info_alternates(const char * alternates, int depth);
f4e51683 228static int git_open_noatime(const char *name);
c2f493a4 229
ddd5d056
JH
230/*
231 * Prepare alternate object database registry.
d5a63b99
JH
232 *
233 * The variable alt_odb_list points at the list of struct
234 * alternate_object_database. The elements on this list come from
235 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
236 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
237 * whose contents is similar to that environment variable but can be
238 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
239 * contains "/the/directory/corresponding/to/.git/objects/...", while
240 * its name points just after the slash at the end of ".git/objects/"
241 * in the example above, and has enough space to hold 40-byte hex
242 * SHA1, an extra slash for the first level indirection, and the
243 * terminating NUL.
ddd5d056 244 */
c2f493a4 245static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
ace1534d 246{
1494e038 247 const char *objdir = get_object_directory();
c2f493a4
MW
248 struct alternate_object_database *ent;
249 struct alternate_object_database *alt;
250 /* 43 = 40-byte + 2 '/' + terminating NUL */
251 int pfxlen = len;
252 int entlen = pfxlen + 43;
ccfd3e99 253 int base_len = -1;
d5a63b99 254
85dadc38 255 if (!is_absolute_path(entry) && relative_base) {
c2f493a4
MW
256 /* Relative alt-odb */
257 if (base_len < 0)
258 base_len = strlen(relative_base) + 1;
259 entlen += base_len;
260 pfxlen += base_len;
261 }
262 ent = xmalloc(sizeof(*ent) + entlen);
263
85dadc38 264 if (!is_absolute_path(entry) && relative_base) {
c2f493a4
MW
265 memcpy(ent->base, relative_base, base_len - 1);
266 ent->base[base_len - 1] = '/';
267 memcpy(ent->base + base_len, entry, len);
268 }
269 else
270 memcpy(ent->base, entry, pfxlen);
271
272 ent->name = ent->base + pfxlen + 1;
273 ent->base[pfxlen + 3] = '/';
274 ent->base[pfxlen] = ent->base[entlen-1] = 0;
275
276 /* Detect cases where alternate disappeared */
90b4a71c 277 if (!is_directory(ent->base)) {
c2f493a4
MW
278 error("object directory %s does not exist; "
279 "check .git/objects/info/alternates.",
280 ent->base);
281 free(ent);
282 return -1;
283 }
284
285 /* Prevent the common mistake of listing the same
286 * thing twice, or object directory itself.
287 */
288 for (alt = alt_odb_list; alt; alt = alt->next) {
289 if (!memcmp(ent->base, alt->base, pfxlen)) {
290 free(ent);
291 return -1;
292 }
293 }
294 if (!memcmp(ent->base, objdir, pfxlen)) {
295 free(ent);
296 return -1;
297 }
298
299 /* add the alternate entry */
300 *alt_odb_tail = ent;
301 alt_odb_tail = &(ent->next);
302 ent->next = NULL;
303
304 /* recursively add alternates */
305 read_info_alternates(ent->base, depth + 1);
306
307 ent->base[pfxlen] = '/';
308
309 return 0;
310}
311
312static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
313 const char *relative_base, int depth)
314{
315 const char *cp, *last;
316
317 if (depth > 5) {
318 error("%s: ignoring alternate object stores, nesting too deep.",
319 relative_base);
320 return;
321 }
322
d5a63b99 323 last = alt;
9577e7e3
JH
324 while (last < ep) {
325 cp = last;
326 if (cp < ep && *cp == '#') {
327 while (cp < ep && *cp != sep)
328 cp++;
329 last = cp + 1;
330 continue;
331 }
c2f493a4
MW
332 while (cp < ep && *cp != sep)
333 cp++;
d5a63b99 334 if (last != cp) {
85dadc38 335 if (!is_absolute_path(last) && depth) {
c2f493a4
MW
336 error("%s: ignoring relative alternate object store %s",
337 relative_base, last);
338 } else {
339 link_alt_odb_entry(last, cp - last,
340 relative_base, depth);
1494e038 341 }
d5a63b99 342 }
9577e7e3 343 while (cp < ep && *cp == sep)
d5a63b99
JH
344 cp++;
345 last = cp;
9577e7e3 346 }
d5a63b99
JH
347}
348
c2f493a4 349static void read_info_alternates(const char * relative_base, int depth)
d5a63b99 350{
9577e7e3 351 char *map;
dc49cd76 352 size_t mapsz;
d5a63b99 353 struct stat st;
9cb18f56
JM
354 const char alt_file_name[] = "info/alternates";
355 /* Given that relative_base is no longer than PATH_MAX,
356 ensure that "path" has enough space to append "/", the
357 file name, "info/alternates", and a trailing NUL. */
358 char path[PATH_MAX + 1 + sizeof alt_file_name];
c2f493a4 359 int fd;
d5a63b99 360
9cb18f56 361 sprintf(path, "%s/%s", relative_base, alt_file_name);
f4e51683 362 fd = git_open_noatime(path);
d5a63b99
JH
363 if (fd < 0)
364 return;
365 if (fstat(fd, &st) || (st.st_size == 0)) {
366 close(fd);
9a217f2a 367 return;
ace1534d 368 }
dc49cd76
SP
369 mapsz = xsize_t(st.st_size);
370 map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0);
d5a63b99 371 close(fd);
d5a63b99 372
dc49cd76 373 link_alt_odb_entries(map, map + mapsz, '\n', relative_base, depth);
c2f493a4 374
dc49cd76 375 munmap(map, mapsz);
ace1534d
JH
376}
377
bef70b22
DB
378void add_to_alternates_file(const char *reference)
379{
380 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
acd3b9ec 381 int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR);
bef70b22
DB
382 char *alt = mkpath("%s/objects\n", reference);
383 write_or_die(fd, alt, strlen(alt));
384 if (commit_lock_file(lock))
385 die("could not close alternates file");
386 if (alt_odb_tail)
387 link_alt_odb_entries(alt, alt + strlen(alt), '\n', NULL, 0);
388}
389
d79796bc
JH
390void foreach_alt_odb(alt_odb_fn fn, void *cb)
391{
392 struct alternate_object_database *ent;
393
394 prepare_alt_odb();
395 for (ent = alt_odb_list; ent; ent = ent->next)
396 if (fn(ent, cb))
397 return;
398}
399
c2f493a4
MW
400void prepare_alt_odb(void)
401{
554fe20d 402 const char *alt;
c2f493a4 403
7dc24aa5
SP
404 if (alt_odb_tail)
405 return;
406
c2f493a4
MW
407 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
408 if (!alt) alt = "";
409
c2f493a4 410 alt_odb_tail = &alt_odb_list;
80ba074f 411 link_alt_odb_entries(alt, alt + strlen(alt), PATH_SEP, NULL, 0);
c2f493a4
MW
412
413 read_info_alternates(get_object_directory(), 0);
414}
415
0f4dc14a 416static int has_loose_object_local(const unsigned char *sha1)
ace1534d 417{
ace1534d 418 char *name = sha1_file_name(sha1);
0f4dc14a
BC
419 return !access(name, F_OK);
420}
ace1534d 421
0f4dc14a
BC
422int has_loose_object_nonlocal(const unsigned char *sha1)
423{
424 struct alternate_object_database *alt;
9a217f2a 425 prepare_alt_odb();
d5a63b99 426 for (alt = alt_odb_list; alt; alt = alt->next) {
0f4dc14a 427 fill_sha1_path(alt->name, sha1);
c529d75a
LT
428 if (!access(alt->base, F_OK))
429 return 1;
ace1534d 430 }
c529d75a 431 return 0;
ace1534d
JH
432}
433
0f4dc14a
BC
434static int has_loose_object(const unsigned char *sha1)
435{
436 return has_loose_object_local(sha1) ||
437 has_loose_object_nonlocal(sha1);
438}
439
60bb8b14 440static unsigned int pack_used_ctr;
a53128b6
SP
441static unsigned int pack_mmap_calls;
442static unsigned int peak_pack_open_windows;
443static unsigned int pack_open_windows;
c7934306
SP
444static unsigned int pack_open_fds;
445static unsigned int pack_max_fds;
a53128b6 446static size_t peak_pack_mapped;
60bb8b14 447static size_t pack_mapped;
9a217f2a 448struct packed_git *packed_git;
1f688557 449
b79d18c9 450void pack_report(void)
a53128b6
SP
451{
452 fprintf(stderr,
e05db0fd
PR
453 "pack_report: getpagesize() = %10" SZ_FMT "\n"
454 "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
455 "pack_report: core.packedGitLimit = %10" SZ_FMT "\n",
9e42d6a1
SP
456 sz_fmt(getpagesize()),
457 sz_fmt(packed_git_window_size),
458 sz_fmt(packed_git_limit));
a53128b6
SP
459 fprintf(stderr,
460 "pack_report: pack_used_ctr = %10u\n"
461 "pack_report: pack_mmap_calls = %10u\n"
462 "pack_report: pack_open_windows = %10u / %10u\n"
e05db0fd
PR
463 "pack_report: pack_mapped = "
464 "%10" SZ_FMT " / %10" SZ_FMT "\n",
a53128b6
SP
465 pack_used_ctr,
466 pack_mmap_calls,
467 pack_open_windows, peak_pack_open_windows,
9e42d6a1 468 sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped));
a53128b6
SP
469}
470
42873078 471static int check_packed_git_idx(const char *path, struct packed_git *p)
1f688557
JH
472{
473 void *idx_map;
42873078 474 struct pack_idx_header *hdr;
dc49cd76 475 size_t idx_size;
74e34e1f 476 uint32_t version, nr, i, *index;
f4e51683 477 int fd = git_open_noatime(path);
1f688557 478 struct stat st;
42873078 479
1f688557
JH
480 if (fd < 0)
481 return -1;
482 if (fstat(fd, &st)) {
483 close(fd);
484 return -1;
485 }
dc49cd76 486 idx_size = xsize_t(st.st_size);
2d88451b
SP
487 if (idx_size < 4 * 256 + 20 + 20) {
488 close(fd);
489 return error("index file %s is too small", path);
490 }
c4712e45 491 idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
1f688557 492 close(fd);
1f688557 493
42873078
NP
494 hdr = idx_map;
495 if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) {
74e34e1f
NP
496 version = ntohl(hdr->idx_version);
497 if (version < 2 || version > 2) {
498 munmap(idx_map, idx_size);
6e1c2344 499 return error("index file %s is version %"PRIu32
74e34e1f
NP
500 " and is not supported by this binary"
501 " (try upgrading GIT to a newer version)",
502 path, version);
503 }
504 } else
505 version = 1;
df1b059d 506
1f688557 507 nr = 0;
42873078 508 index = idx_map;
74e34e1f
NP
509 if (version > 1)
510 index += 2; /* skip index header */
1f688557 511 for (i = 0; i < 256; i++) {
326bf396 512 uint32_t n = ntohl(index[i]);
2d88451b
SP
513 if (n < nr) {
514 munmap(idx_map, idx_size);
df1b059d 515 return error("non-monotonic index %s", path);
2d88451b 516 }
1f688557
JH
517 nr = n;
518 }
519
74e34e1f
NP
520 if (version == 1) {
521 /*
522 * Total size:
523 * - 256 index entries 4 bytes each
524 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
525 * - 20-byte SHA1 of the packfile
526 * - 20-byte SHA1 file checksum
527 */
528 if (idx_size != 4*256 + nr * 24 + 20 + 20) {
529 munmap(idx_map, idx_size);
eef427a0 530 return error("wrong index v1 file size in %s", path);
74e34e1f
NP
531 }
532 } else if (version == 2) {
533 /*
534 * Minimum size:
535 * - 8 bytes of header
536 * - 256 index entries 4 bytes each
537 * - 20-byte sha1 entry * nr
538 * - 4-byte crc entry * nr
539 * - 4-byte offset entry * nr
540 * - 20-byte SHA1 of the packfile
541 * - 20-byte SHA1 file checksum
542 * And after the 4-byte offset table might be a
543 * variable sized table containing 8-byte entries
544 * for offsets larger than 2^31.
545 */
546 unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20;
1164f1e4
LT
547 unsigned long max_size = min_size;
548 if (nr)
549 max_size += (nr - 1)*8;
550 if (idx_size < min_size || idx_size > max_size) {
74e34e1f 551 munmap(idx_map, idx_size);
eef427a0 552 return error("wrong index v2 file size in %s", path);
74e34e1f 553 }
7109c889
JH
554 if (idx_size != min_size &&
555 /*
556 * make sure we can deal with large pack offsets.
557 * 31-bit signed offset won't be enough, neither
558 * 32-bit unsigned one will be.
559 */
560 (sizeof(off_t) <= 4)) {
561 munmap(idx_map, idx_size);
562 return error("pack too large for current definition of off_t in %s", path);
74e34e1f 563 }
2d88451b 564 }
1f688557 565
74e34e1f 566 p->index_version = version;
42873078
NP
567 p->index_data = idx_map;
568 p->index_size = idx_size;
57059091 569 p->num_objects = nr;
1f688557
JH
570 return 0;
571}
572
bc8e478a 573int open_pack_index(struct packed_git *p)
d079837e
SP
574{
575 char *idx_name;
576 int ret;
577
578 if (p->index_data)
579 return 0;
580
581 idx_name = xstrdup(p->pack_name);
582 strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx");
583 ret = check_packed_git_idx(idx_name, p);
584 free(idx_name);
585 return ret;
586}
587
11daf39b
SP
588static void scan_windows(struct packed_git *p,
589 struct packed_git **lru_p,
590 struct pack_window **lru_w,
591 struct pack_window **lru_l)
1f688557 592{
11daf39b
SP
593 struct pack_window *w, *w_l;
594
595 for (w_l = NULL, w = p->windows; w; w = w->next) {
596 if (!w->inuse_cnt) {
597 if (!*lru_w || w->last_used < (*lru_w)->last_used) {
598 *lru_p = p;
599 *lru_w = w;
600 *lru_l = w_l;
54044bf8 601 }
54044bf8 602 }
11daf39b 603 w_l = w;
f9253394 604 }
11daf39b
SP
605}
606
d1efefa4 607static int unuse_one_window(struct packed_git *current, int keep_fd)
11daf39b
SP
608{
609 struct packed_git *p, *lru_p = NULL;
610 struct pack_window *lru_w = NULL, *lru_l = NULL;
611
612 if (current)
613 scan_windows(current, &lru_p, &lru_w, &lru_l);
614 for (p = packed_git; p; p = p->next)
615 scan_windows(p, &lru_p, &lru_w, &lru_l);
54044bf8
SP
616 if (lru_p) {
617 munmap(lru_w->base, lru_w->len);
618 pack_mapped -= lru_w->len;
619 if (lru_l)
620 lru_l->next = lru_w->next;
621 else {
622 lru_p->windows = lru_w->next;
d131b7af
SP
623 if (!lru_p->windows && lru_p->pack_fd != -1
624 && lru_p->pack_fd != keep_fd) {
54044bf8 625 close(lru_p->pack_fd);
c7934306 626 pack_open_fds--;
54044bf8
SP
627 lru_p->pack_fd = -1;
628 }
629 }
630 free(lru_w);
a53128b6 631 pack_open_windows--;
54044bf8
SP
632 return 1;
633 }
634 return 0;
f9253394
JH
635}
636
d1efefa4 637void release_pack_memory(size_t need, int fd)
97bfeb34
SP
638{
639 size_t cur = pack_mapped;
d1efefa4 640 while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd))
97bfeb34
SP
641 ; /* nothing */
642}
643
58ecbd5e
JN
644void *xmmap(void *start, size_t length,
645 int prot, int flags, int fd, off_t offset)
646{
647 void *ret = mmap(start, length, prot, flags, fd, offset);
648 if (ret == MAP_FAILED) {
649 if (!length)
650 return NULL;
651 release_pack_memory(length, fd);
652 ret = mmap(start, length, prot, flags, fd, offset);
653 if (ret == MAP_FAILED)
654 die_errno("Out of memory? mmap failed");
655 }
656 return ret;
657}
658
c9ced051
SP
659void close_pack_windows(struct packed_git *p)
660{
661 while (p->windows) {
662 struct pack_window *w = p->windows;
663
664 if (w->inuse_cnt)
665 die("pack '%s' still has open windows to it",
666 p->pack_name);
667 munmap(w->base, w->len);
668 pack_mapped -= w->len;
669 pack_open_windows--;
670 p->windows = w->next;
671 free(w);
672 }
673}
674
03e79c88 675void unuse_pack(struct pack_window **w_cursor)
f9253394 676{
03e79c88
SP
677 struct pack_window *w = *w_cursor;
678 if (w) {
679 w->inuse_cnt--;
680 *w_cursor = NULL;
681 }
1f688557
JH
682}
683
fa5fc15d
SP
684void close_pack_index(struct packed_git *p)
685{
686 if (p->index_data) {
687 munmap((void *)p->index_data, p->index_size);
688 p->index_data = NULL;
689 }
690}
691
c74faea1
NP
692/*
693 * This is used by git-repack in case a newly created pack happens to
694 * contain the same set of objects as an existing one. In that case
695 * the resulting file might be different even if its name would be the
696 * same. It is best to close any reference to the old pack before it is
697 * replaced on disk. Of course no index pointers nor windows for given pack
698 * must subsist at this point. If ever objects from this pack are requested
699 * again, the new version of the pack will be reinitialized through
700 * reprepare_packed_git().
701 */
702void free_pack_by_name(const char *pack_name)
703{
704 struct packed_git *p, **pp = &packed_git;
705
706 while (*pp) {
707 p = *pp;
708 if (strcmp(pack_name, p->pack_name) == 0) {
fa3a0c94 709 clear_delta_base_cache();
c74faea1 710 close_pack_windows(p);
c7934306 711 if (p->pack_fd != -1) {
c74faea1 712 close(p->pack_fd);
c7934306
SP
713 pack_open_fds--;
714 }
fa5fc15d 715 close_pack_index(p);
c74faea1
NP
716 free(p->bad_object_sha1);
717 *pp = p->next;
718 free(p);
719 return;
720 }
721 pp = &p->next;
722 }
723}
724
3cf8b462
SP
725/*
726 * Do not call this directly as this leaks p->pack_fd on error return;
727 * call open_packed_git() instead.
728 */
729static int open_packed_git_1(struct packed_git *p)
1f688557 730{
9bc879c1
SP
731 struct stat st;
732 struct pack_header hdr;
733 unsigned char sha1[20];
734 unsigned char *idx_sha1;
2c039da8 735 long fd_flag;
9bc879c1 736
d079837e
SP
737 if (!p->index_data && open_pack_index(p))
738 return error("packfile %s index unavailable", p->pack_name);
739
c7934306
SP
740 if (!pack_max_fds) {
741 struct rlimit lim;
742 unsigned int max_fds;
743
744 if (getrlimit(RLIMIT_NOFILE, &lim))
745 die_errno("cannot get RLIMIT_NOFILE");
746
747 max_fds = lim.rlim_cur;
748
749 /* Save 3 for stdin/stdout/stderr, 22 for work */
750 if (25 < max_fds)
751 pack_max_fds = max_fds - 25;
752 else
753 pack_max_fds = 1;
754 }
755
756 while (pack_max_fds <= pack_open_fds && unuse_one_window(NULL, -1))
757 ; /* nothing */
758
f4e51683 759 p->pack_fd = git_open_noatime(p->pack_name);
9bc879c1 760 if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
072db278 761 return -1;
c7934306 762 pack_open_fds++;
9bc879c1
SP
763
764 /* If we created the struct before we had the pack we lack size. */
bf592c50 765 if (!p->pack_size) {
bf592c50 766 if (!S_ISREG(st.st_mode))
072db278 767 return error("packfile %s not a regular file", p->pack_name);
bf592c50 768 p->pack_size = st.st_size;
9bc879c1 769 } else if (p->pack_size != st.st_size)
072db278 770 return error("packfile %s size changed", p->pack_name);
9bc879c1 771
2c039da8
JH
772 /* We leave these file descriptors open with sliding mmap;
773 * there is no point keeping them open across exec(), though.
774 */
775 fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
776 if (fd_flag < 0)
072db278 777 return error("cannot determine file descriptor flags");
2c039da8
JH
778 fd_flag |= FD_CLOEXEC;
779 if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
072db278 780 return error("cannot set FD_CLOEXEC");
2c039da8 781
9bc879c1 782 /* Verify we recognize this pack file format. */
e6e2bd62 783 if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
072db278 784 return error("file %s is far too short to be a packfile", p->pack_name);
9bc879c1 785 if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
072db278 786 return error("file %s is not a GIT packfile", p->pack_name);
9bc879c1 787 if (!pack_version_ok(hdr.hdr_version))
6e1c2344
RJ
788 return error("packfile %s is version %"PRIu32" and not"
789 " supported (try upgrading GIT to a newer version)",
9bc879c1
SP
790 p->pack_name, ntohl(hdr.hdr_version));
791
792 /* Verify the pack matches its index. */
57059091 793 if (p->num_objects != ntohl(hdr.hdr_entries))
6e1c2344
RJ
794 return error("packfile %s claims to have %"PRIu32" objects"
795 " while index indicates %"PRIu32" objects",
57059091
NP
796 p->pack_name, ntohl(hdr.hdr_entries),
797 p->num_objects);
9bc879c1 798 if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
072db278 799 return error("end of packfile %s is unavailable", p->pack_name);
e6e2bd62 800 if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
072db278 801 return error("packfile %s signature is unavailable", p->pack_name);
42873078 802 idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40;
9bc879c1 803 if (hashcmp(sha1, idx_sha1))
072db278
SP
804 return error("packfile %s does not match index", p->pack_name);
805 return 0;
9bc879c1
SP
806}
807
3cf8b462
SP
808static int open_packed_git(struct packed_git *p)
809{
810 if (!open_packed_git_1(p))
811 return 0;
812 if (p->pack_fd != -1) {
813 close(p->pack_fd);
c7934306 814 pack_open_fds--;
3cf8b462
SP
815 p->pack_fd = -1;
816 }
817 return -1;
818}
819
c4001d92 820static int in_window(struct pack_window *win, off_t offset)
60bb8b14
SP
821{
822 /* We must promise at least 20 bytes (one hash) after the
823 * offset is available from this window, otherwise the offset
824 * is not actually in this window and a different window (which
825 * has that one hash excess) must be used. This is to support
826 * the object header and delta base parsing routines below.
827 */
828 off_t win_off = win->offset;
829 return win_off <= offset
830 && (offset + 20) <= (win_off + win->len);
831}
832
4b25d091 833unsigned char *use_pack(struct packed_git *p,
03e79c88 834 struct pack_window **w_cursor,
c4001d92 835 off_t offset,
03e79c88 836 unsigned int *left)
9bc879c1 837{
60bb8b14 838 struct pack_window *win = *w_cursor;
03e79c88 839
a9d98a14 840 /* Since packfiles end in a hash of their content and it's
60bb8b14
SP
841 * pointless to ask for an offset into the middle of that
842 * hash, and the in_window function above wouldn't match
843 * don't allow an offset too close to the end of the file.
844 */
d131b7af
SP
845 if (!p->pack_size && p->pack_fd == -1 && open_packed_git(p))
846 die("packfile %s cannot be accessed", p->pack_name);
60bb8b14
SP
847 if (offset > (p->pack_size - 20))
848 die("offset beyond end of packfile (truncated pack?)");
849
850 if (!win || !in_window(win, offset)) {
851 if (win)
852 win->inuse_cnt--;
853 for (win = p->windows; win; win = win->next) {
854 if (in_window(win, offset))
855 break;
856 }
857 if (!win) {
78a28df9 858 size_t window_align = packed_git_window_size / 2;
dc49cd76 859 off_t len;
d131b7af
SP
860
861 if (p->pack_fd == -1 && open_packed_git(p))
862 die("packfile %s cannot be accessed", p->pack_name);
863
60bb8b14 864 win = xcalloc(1, sizeof(*win));
78a28df9 865 win->offset = (offset / window_align) * window_align;
dc49cd76
SP
866 len = p->pack_size - win->offset;
867 if (len > packed_git_window_size)
868 len = packed_git_window_size;
869 win->len = (size_t)len;
60bb8b14 870 pack_mapped += win->len;
11daf39b 871 while (packed_git_limit < pack_mapped
d1efefa4 872 && unuse_one_window(p, p->pack_fd))
60bb8b14 873 ; /* nothing */
c4712e45 874 win->base = xmmap(NULL, win->len,
60bb8b14
SP
875 PROT_READ, MAP_PRIVATE,
876 p->pack_fd, win->offset);
877 if (win->base == MAP_FAILED)
73b4e4be
SP
878 die("packfile %s cannot be mapped: %s",
879 p->pack_name,
880 strerror(errno));
d131b7af
SP
881 if (!win->offset && win->len == p->pack_size
882 && !p->do_not_close) {
883 close(p->pack_fd);
884 pack_open_fds--;
885 p->pack_fd = -1;
886 }
a53128b6
SP
887 pack_mmap_calls++;
888 pack_open_windows++;
889 if (pack_mapped > peak_pack_mapped)
890 peak_pack_mapped = pack_mapped;
891 if (pack_open_windows > peak_pack_open_windows)
892 peak_pack_open_windows = pack_open_windows;
60bb8b14
SP
893 win->next = p->windows;
894 p->windows = win;
895 }
1f688557 896 }
03e79c88
SP
897 if (win != *w_cursor) {
898 win->last_used = pack_used_ctr++;
899 win->inuse_cnt++;
900 *w_cursor = win;
901 }
60bb8b14 902 offset -= win->offset;
03e79c88 903 if (left)
dc49cd76 904 *left = win->len - xsize_t(offset);
03e79c88 905 return win->base + offset;
1f688557
JH
906}
907
27d69a46
NP
908static struct packed_git *alloc_packed_git(int extra)
909{
910 struct packed_git *p = xmalloc(sizeof(*p) + extra);
911 memset(p, 0, sizeof(*p));
912 p->pack_fd = -1;
913 return p;
914}
915
e0500293
JN
916static void try_to_free_pack_memory(size_t size)
917{
918 release_pack_memory(size, -1);
919}
920
42873078 921struct packed_git *add_packed_git(const char *path, int path_len, int local)
1f688557 922{
e0500293 923 static int have_set_try_to_free_routine;
1f688557 924 struct stat st;
27d69a46 925 struct packed_git *p = alloc_packed_git(path_len + 2);
1f688557 926
e0500293
JN
927 if (!have_set_try_to_free_routine) {
928 have_set_try_to_free_routine = 1;
929 set_try_to_free_routine(try_to_free_pack_memory);
930 }
931
42873078
NP
932 /*
933 * Make sure a corresponding .pack file exists and that
934 * the index looks sane.
935 */
936 path_len -= strlen(".idx");
27d69a46
NP
937 if (path_len < 1) {
938 free(p);
1f688557 939 return NULL;
27d69a46 940 }
42873078 941 memcpy(p->pack_name, path, path_len);
8d25931d
BC
942
943 strcpy(p->pack_name + path_len, ".keep");
944 if (!access(p->pack_name, F_OK))
945 p->pack_keep = 1;
946
42873078 947 strcpy(p->pack_name + path_len, ".pack");
d079837e 948 if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
42873078 949 free(p);
1f688557
JH
950 return NULL;
951 }
42873078 952
1f688557
JH
953 /* ok, it looks sane as far as we can check without
954 * actually mapping the pack file.
955 */
1f688557 956 p->pack_size = st.st_size;
9d835df2 957 p->pack_local = local;
b867092f 958 p->mtime = st.st_mtime;
42873078
NP
959 if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1))
960 hashclr(p->sha1);
1f688557
JH
961 return p;
962}
963
7b64469a 964struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path)
c508df5e 965{
42873078 966 const char *path = sha1_pack_name(sha1);
27d69a46 967 struct packed_git *p = alloc_packed_git(strlen(path) + 1);
bf592c50 968
27d69a46
NP
969 strcpy(p->pack_name, path);
970 hashcpy(p->sha1, sha1);
42873078
NP
971 if (check_packed_git_idx(idx_path, p)) {
972 free(p);
bf592c50 973 return NULL;
42873078 974 }
bf592c50 975
bf592c50
DB
976 return p;
977}
978
979void install_packed_git(struct packed_git *pack)
980{
c7934306
SP
981 if (pack->pack_fd != -1)
982 pack_open_fds++;
983
bf592c50
DB
984 pack->next = packed_git;
985 packed_git = pack;
986}
987
9d835df2 988static void prepare_packed_git_one(char *objdir, int local)
1f688557 989{
9cb18f56
JM
990 /* Ensure that this buffer is large enough so that we can
991 append "/pack/" without clobbering the stack even if
992 strlen(objdir) were PATH_MAX. */
993 char path[PATH_MAX + 1 + 4 + 1 + 1];
1f688557
JH
994 int len;
995 DIR *dir;
996 struct dirent *de;
997
998 sprintf(path, "%s/pack", objdir);
999 len = strlen(path);
1000 dir = opendir(path);
b5b16990 1001 if (!dir) {
26125f6b 1002 if (errno != ENOENT)
bd2afde8 1003 error("unable to open object pack directory: %s: %s",
26125f6b 1004 path, strerror(errno));
1f688557 1005 return;
b5b16990 1006 }
1f688557
JH
1007 path[len++] = '/';
1008 while ((de = readdir(dir)) != NULL) {
1009 int namelen = strlen(de->d_name);
1010 struct packed_git *p;
1011
5bb1cda5 1012 if (!has_extension(de->d_name, ".idx"))
1f688557
JH
1013 continue;
1014
9cb18f56
JM
1015 if (len + namelen + 1 > sizeof(path))
1016 continue;
1017
54a15a8d 1018 /* Don't reopen a pack we already have. */
1f688557 1019 strcpy(path + len, de->d_name);
86f7780c
JK
1020 for (p = packed_git; p; p = p->next) {
1021 if (!memcmp(path, p->pack_name, len + namelen - 4))
1022 break;
1023 }
1024 if (p)
1025 continue;
54a15a8d
SP
1026 /* See if it really is a valid .idx file with corresponding
1027 * .pack file that we can map.
1028 */
9d835df2 1029 p = add_packed_git(path, len + namelen, local);
1f688557
JH
1030 if (!p)
1031 continue;
625e9421 1032 install_packed_git(p);
1f688557 1033 }
5b35bcd5 1034 closedir(dir);
1f688557
JH
1035}
1036
b867092f
JH
1037static int sort_pack(const void *a_, const void *b_)
1038{
1039 struct packed_git *a = *((struct packed_git **)a_);
1040 struct packed_git *b = *((struct packed_git **)b_);
1041 int st;
1042
1043 /*
1044 * Local packs tend to contain objects specific to our
1045 * variant of the project than remote ones. In addition,
1046 * remote ones could be on a network mounted filesystem.
1047 * Favor local ones for these reasons.
1048 */
1049 st = a->pack_local - b->pack_local;
1050 if (st)
1051 return -st;
1052
1053 /*
1054 * Younger packs tend to contain more recent objects,
1055 * and more recent objects tend to get accessed more
1056 * often.
1057 */
1058 if (a->mtime < b->mtime)
1059 return 1;
1060 else if (a->mtime == b->mtime)
1061 return 0;
1062 return -1;
1063}
1064
1065static void rearrange_packed_git(void)
1066{
1067 struct packed_git **ary, *p;
1068 int i, n;
1069
1070 for (n = 0, p = packed_git; p; p = p->next)
1071 n++;
1072 if (n < 2)
1073 return;
1074
1075 /* prepare an array of packed_git for easier sorting */
1076 ary = xcalloc(n, sizeof(struct packed_git *));
1077 for (n = 0, p = packed_git; p; p = p->next)
1078 ary[n++] = p;
1079
1080 qsort(ary, n, sizeof(struct packed_git *), sort_pack);
1081
1082 /* link them back again */
1083 for (i = 0; i < n - 1; i++)
1084 ary[i]->next = ary[i + 1];
1085 ary[n - 1]->next = NULL;
1086 packed_git = ary[0];
1087
1088 free(ary);
1089}
1090
637cdd9d 1091static int prepare_packed_git_run_once = 0;
9a217f2a 1092void prepare_packed_git(void)
1f688557 1093{
d5a63b99 1094 struct alternate_object_database *alt;
1f688557 1095
637cdd9d 1096 if (prepare_packed_git_run_once)
1f688557 1097 return;
9d835df2 1098 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 1099 prepare_alt_odb();
d5a63b99 1100 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 1101 alt->name[-1] = 0;
9d835df2 1102 prepare_packed_git_one(alt->base, 0);
1494e038 1103 alt->name[-1] = '/';
1f688557 1104 }
b867092f 1105 rearrange_packed_git();
637cdd9d
JK
1106 prepare_packed_git_run_once = 1;
1107}
1108
fc04c412 1109void reprepare_packed_git(void)
637cdd9d 1110{
4b480c67 1111 discard_revindex();
637cdd9d
JK
1112 prepare_packed_git_run_once = 0;
1113 prepare_packed_git();
1f688557
JH
1114}
1115
8eca0b47
NP
1116static void mark_bad_packed_object(struct packed_git *p,
1117 const unsigned char *sha1)
1118{
1119 unsigned i;
1120 for (i = 0; i < p->num_bad_objects; i++)
1121 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1122 return;
1123 p->bad_object_sha1 = xrealloc(p->bad_object_sha1, 20 * (p->num_bad_objects + 1));
1124 hashcpy(p->bad_object_sha1 + 20 * p->num_bad_objects, sha1);
1125 p->num_bad_objects++;
1126}
1127
b6c4cecc 1128static const struct packed_git *has_packed_and_bad(const unsigned char *sha1)
ac939109
NP
1129{
1130 struct packed_git *p;
1131 unsigned i;
1132
1133 for (p = packed_git; p; p = p->next)
1134 for (i = 0; i < p->num_bad_objects; i++)
1135 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
b6c4cecc
JH
1136 return p;
1137 return NULL;
ac939109
NP
1138}
1139
5d6ccf5c 1140int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
0fcfd160
LT
1141{
1142 unsigned char real_sha1[20];
7cfb5f36 1143 hash_sha1_file(map, size, type, real_sha1);
a89fccd2 1144 return hashcmp(sha1, real_sha1) ? -1 : 0;
0fcfd160
LT
1145}
1146
f4e51683 1147static int git_open_noatime(const char *name)
44d1c19e
LT
1148{
1149 static int sha1_file_open_flag = O_NOATIME;
44d1c19e 1150
f2e872aa
SP
1151 for (;;) {
1152 int fd = open(name, O_RDONLY | sha1_file_open_flag);
44d1c19e 1153 if (fd >= 0)
f2e872aa
SP
1154 return fd;
1155
f2e872aa
SP
1156 /* Might the failure be due to O_NOATIME? */
1157 if (errno != ENOENT && sha1_file_open_flag) {
44d1c19e 1158 sha1_file_open_flag = 0;
f2e872aa
SP
1159 continue;
1160 }
1161
1162 return -1;
44d1c19e 1163 }
44d1c19e
LT
1164}
1165
1166static int open_sha1_file(const unsigned char *sha1)
1167{
1168 int fd;
1169 char *name = sha1_file_name(sha1);
1170 struct alternate_object_database *alt;
1171
f4e51683 1172 fd = git_open_noatime(name);
44d1c19e
LT
1173 if (fd >= 0)
1174 return fd;
1175
1176 prepare_alt_odb();
1177 errno = ENOENT;
1178 for (alt = alt_odb_list; alt; alt = alt->next) {
1179 name = alt->name;
1180 fill_sha1_path(name, sha1);
f4e51683 1181 fd = git_open_noatime(alt->base);
44d1c19e
LT
1182 if (fd >= 0)
1183 return fd;
1184 }
1185 return -1;
1186}
1187
4175e9e3 1188static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
0fcfd160 1189{
0fcfd160 1190 void *map;
144bde78 1191 int fd;
ace1534d 1192
44d1c19e
LT
1193 fd = open_sha1_file(sha1);
1194 map = NULL;
1195 if (fd >= 0) {
1196 struct stat st;
0fcfd160 1197
44d1c19e
LT
1198 if (!fstat(fd, &st)) {
1199 *size = xsize_t(st.st_size);
1200 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
144bde78 1201 }
44d1c19e 1202 close(fd);
0fcfd160 1203 }
0fcfd160
LT
1204 return map;
1205}
1206
726f852b 1207static int legacy_loose_object(unsigned char *map)
bb6b8e4f
JH
1208{
1209 unsigned int word;
1210
1211 /*
1212 * Is it a zlib-compressed buffer? If so, the first byte
1213 * must be 0x78 (15-bit window size, deflated), and the
1214 * first 16-bit word is evenly divisible by 31
1215 */
1216 word = (map[0] << 8) + map[1];
1217 if (map[0] == 0x78 && !(word % 31))
1218 return 1;
1219 else
1220 return 0;
1221}
1222
09ded04b
NP
1223unsigned long unpack_object_header_buffer(const unsigned char *buf,
1224 unsigned long len, enum object_type *type, unsigned long *sizep)
c4483576 1225{
ad1ed5ee 1226 unsigned shift;
48fb7deb 1227 unsigned long size, c;
ad1ed5ee
JH
1228 unsigned long used = 0;
1229
1230 c = buf[used++];
1231 *type = (c >> 4) & 7;
1232 size = c & 15;
1233 shift = 4;
1234 while (c & 0x80) {
f630cfda 1235 if (len <= used || bitsizeof(long) <= shift) {
09ded04b 1236 error("bad object header");
ad1ed5ee 1237 return 0;
09ded04b 1238 }
ad1ed5ee
JH
1239 c = buf[used++];
1240 size += (c & 0x7f) << shift;
1241 shift += 7;
1242 }
1243 *sizep = size;
1244 return used;
1245}
1246
1247static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
1248{
1249 unsigned long size, used;
1250 static const char valid_loose_object_type[8] = {
1251 0, /* OBJ_EXT */
1252 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
1253 0, /* "delta" and others are invalid in a loose object */
93821bd9 1254 };
ad1ed5ee 1255 enum object_type type;
93821bd9 1256
c4483576
LT
1257 /* Get the data stream */
1258 memset(stream, 0, sizeof(*stream));
1259 stream->next_in = map;
1260 stream->avail_in = mapsize;
1261 stream->next_out = buffer;
93821bd9
LT
1262 stream->avail_out = bufsiz;
1263
bb6b8e4f 1264 if (legacy_loose_object(map)) {
39c68542
LT
1265 git_inflate_init(stream);
1266 return git_inflate(stream, 0);
93821bd9
LT
1267 }
1268
726f852b
NP
1269
1270 /*
1271 * There used to be a second loose object header format which
1272 * was meant to mimic the in-pack format, allowing for direct
1273 * copy of the object data. This format turned up not to be
1274 * really worth it and we don't write it any longer. But we
1275 * can still read it.
1276 */
09ded04b 1277 used = unpack_object_header_buffer(map, mapsize, &type, &size);
ad1ed5ee 1278 if (!used || !valid_loose_object_type[type])
93821bd9 1279 return -1;
ad1ed5ee
JH
1280 map += used;
1281 mapsize -= used;
93821bd9
LT
1282
1283 /* Set up the stream for the rest.. */
1284 stream->next_in = map;
1285 stream->avail_in = mapsize;
39c68542 1286 git_inflate_init(stream);
93821bd9
LT
1287
1288 /* And generate the fake traditional header */
ad1ed5ee 1289 stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
df843662 1290 typename(type), size);
93821bd9 1291 return 0;
c4483576
LT
1292}
1293
7efbff75 1294static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
5180cacc
LT
1295{
1296 int bytes = strlen(buffer) + 1;
3aee68aa 1297 unsigned char *buf = xmallocz(size);
93821bd9 1298 unsigned long n;
7efbff75 1299 int status = Z_OK;
5180cacc 1300
93821bd9
LT
1301 n = stream->total_out - bytes;
1302 if (n > size)
1303 n = size;
1304 memcpy(buf, (char *) buffer + bytes, n);
1305 bytes = n;
456cdf6e
LT
1306 if (bytes <= size) {
1307 /*
1308 * The above condition must be (bytes <= size), not
1309 * (bytes < size). In other words, even though we
ccf5ace0 1310 * expect no more output and set avail_out to zero,
456cdf6e
LT
1311 * the input zlib stream may have bytes that express
1312 * "this concludes the stream", and we *do* want to
1313 * eat that input.
1314 *
1315 * Otherwise we would not be able to test that we
1316 * consumed all the input to reach the expected size;
1317 * we also want to check that zlib tells us that all
1318 * went well with status == Z_STREAM_END at the end.
1319 */
5180cacc
LT
1320 stream->next_out = buf + bytes;
1321 stream->avail_out = size - bytes;
7efbff75 1322 while (status == Z_OK)
39c68542 1323 status = git_inflate(stream, Z_FINISH);
5180cacc 1324 }
456cdf6e 1325 if (status == Z_STREAM_END && !stream->avail_in) {
39c68542 1326 git_inflate_end(stream);
7efbff75
JH
1327 return buf;
1328 }
1329
1330 if (status < 0)
1331 error("corrupt loose object '%s'", sha1_to_hex(sha1));
1332 else if (stream->avail_in)
1333 error("garbage at end of loose object '%s'",
1334 sha1_to_hex(sha1));
1335 free(buf);
1336 return NULL;
5180cacc
LT
1337}
1338
1339/*
1340 * We used to just use "sscanf()", but that's actually way
1341 * too permissive for what we want to check. So do an anal
1342 * object header parse by hand.
1343 */
21666f1a 1344static int parse_sha1_header(const char *hdr, unsigned long *sizep)
5180cacc 1345{
21666f1a 1346 char type[10];
5180cacc
LT
1347 int i;
1348 unsigned long size;
1349
1350 /*
a6080a0a 1351 * The type can be at most ten bytes (including the
5180cacc 1352 * terminating '\0' that we add), and is followed by
21666f1a 1353 * a space.
5180cacc 1354 */
21666f1a 1355 i = 0;
5180cacc
LT
1356 for (;;) {
1357 char c = *hdr++;
1358 if (c == ' ')
1359 break;
21666f1a
NP
1360 type[i++] = c;
1361 if (i >= sizeof(type))
5180cacc 1362 return -1;
5180cacc 1363 }
21666f1a 1364 type[i] = 0;
5180cacc
LT
1365
1366 /*
1367 * The length must follow immediately, and be in canonical
1368 * decimal format (ie "010" is not valid).
1369 */
1370 size = *hdr++ - '0';
1371 if (size > 9)
1372 return -1;
1373 if (size) {
1374 for (;;) {
1375 unsigned long c = *hdr - '0';
1376 if (c > 9)
1377 break;
1378 hdr++;
1379 size = size * 10 + c;
1380 }
1381 }
1382 *sizep = size;
1383
1384 /*
1385 * The length must be followed by a zero byte
1386 */
21666f1a 1387 return *hdr ? -1 : type_from_string(type);
5180cacc
LT
1388}
1389
7efbff75 1390static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
0fcfd160 1391{
5180cacc 1392 int ret;
0fcfd160 1393 z_stream stream;
5180cacc 1394 char hdr[8192];
0fcfd160 1395
5180cacc 1396 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
21666f1a 1397 if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
0fcfd160
LT
1398 return NULL;
1399
7efbff75 1400 return unpack_sha1_rest(&stream, hdr, *size, sha1);
0fcfd160
LT
1401}
1402
54dab52a
NP
1403unsigned long get_size_from_delta(struct packed_git *p,
1404 struct pack_window **w_curs,
1405 off_t curpos)
1406{
1407 const unsigned char *data;
1408 unsigned char delta_head[20], *in;
1409 z_stream stream;
1410 int st;
1411
1412 memset(&stream, 0, sizeof(stream));
1413 stream.next_out = delta_head;
1414 stream.avail_out = sizeof(delta_head);
1415
39c68542 1416 git_inflate_init(&stream);
54dab52a
NP
1417 do {
1418 in = use_pack(p, w_curs, curpos, &stream.avail_in);
1419 stream.next_in = in;
39c68542 1420 st = git_inflate(&stream, Z_FINISH);
54dab52a
NP
1421 curpos += stream.next_in - in;
1422 } while ((st == Z_OK || st == Z_BUF_ERROR) &&
1423 stream.total_out < sizeof(delta_head));
39c68542 1424 git_inflate_end(&stream);
3d77d877
NP
1425 if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) {
1426 error("delta data unpack-initial failed");
1427 return 0;
1428 }
54dab52a
NP
1429
1430 /* Examine the initial part of the delta to figure out
1431 * the result size.
1432 */
1433 data = delta_head;
1434
1435 /* ignore base size */
1436 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1437
1438 /* Read the result size */
1439 return get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1440}
1441
c4001d92 1442static off_t get_delta_base(struct packed_git *p,
03e79c88 1443 struct pack_window **w_curs,
c4001d92 1444 off_t *curpos,
21666f1a 1445 enum object_type type,
c4001d92 1446 off_t delta_obj_offset)
eb32d236 1447{
2b87c45b 1448 unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
c4001d92 1449 off_t base_offset;
eb32d236 1450
8d8a4ea5
SP
1451 /* use_pack() assured us we have [base_info, base_info + 20)
1452 * as a range that we can look at without walking off the
1453 * end of the mapped window. Its actually the hash size
1454 * that is assured. An OFS_DELTA longer than the hash size
1455 * is stupid, as then a REF_DELTA would be smaller to store.
1456 */
21666f1a 1457 if (type == OBJ_OFS_DELTA) {
eb32d236
NP
1458 unsigned used = 0;
1459 unsigned char c = base_info[used++];
1460 base_offset = c & 127;
1461 while (c & 128) {
1462 base_offset += 1;
8723f216 1463 if (!base_offset || MSB(base_offset, 7))
8eca0b47 1464 return 0; /* overflow */
eb32d236
NP
1465 c = base_info[used++];
1466 base_offset = (base_offset << 7) + (c & 127);
1467 }
1468 base_offset = delta_obj_offset - base_offset;
d8f32556 1469 if (base_offset <= 0 || base_offset >= delta_obj_offset)
8eca0b47 1470 return 0; /* out of bound */
2b87c45b 1471 *curpos += used;
21666f1a 1472 } else if (type == OBJ_REF_DELTA) {
eb32d236
NP
1473 /* The base entry _must_ be in the same pack */
1474 base_offset = find_pack_entry_one(base_info, p);
2b87c45b 1475 *curpos += 20;
eb32d236
NP
1476 } else
1477 die("I am totally screwed");
2b87c45b 1478 return base_offset;
eb32d236
NP
1479}
1480
f3bf9224 1481/* forward declaration for a mutually recursive function */
c4001d92 1482static int packed_object_info(struct packed_git *p, off_t offset,
21666f1a 1483 unsigned long *sizep);
f3bf9224 1484
43057304 1485static int packed_delta_info(struct packed_git *p,
03e79c88 1486 struct pack_window **w_curs,
c4001d92 1487 off_t curpos,
21666f1a 1488 enum object_type type,
c4001d92 1489 off_t obj_offset,
43057304 1490 unsigned long *sizep)
5db47c2b 1491{
c4001d92 1492 off_t base_offset;
f3bf9224 1493
21666f1a 1494 base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
3d77d877
NP
1495 if (!base_offset)
1496 return OBJ_BAD;
21666f1a 1497 type = packed_object_info(p, base_offset, NULL);
3d77d877 1498 if (type <= OBJ_NONE) {
08698b1e
NP
1499 struct revindex_entry *revidx;
1500 const unsigned char *base_sha1;
1501 revidx = find_pack_revindex(p, base_offset);
1502 if (!revidx)
1503 return OBJ_BAD;
1504 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
3d77d877
NP
1505 mark_bad_packed_object(p, base_sha1);
1506 type = sha1_object_info(base_sha1, NULL);
1507 if (type <= OBJ_NONE)
1508 return OBJ_BAD;
1509 }
f3bf9224 1510
c62266f3
JH
1511 /* We choose to only get the type of the base object and
1512 * ignore potentially corrupt pack file that expects the delta
1513 * based on a base with a wrong size. This saves tons of
1514 * inflate() calls.
1515 */
3d77d877 1516 if (sizep) {
54dab52a 1517 *sizep = get_size_from_delta(p, w_curs, curpos);
3d77d877
NP
1518 if (*sizep == 0)
1519 type = OBJ_BAD;
1520 }
21666f1a
NP
1521
1522 return type;
5db47c2b
JH
1523}
1524
2b87c45b
NP
1525static int unpack_object_header(struct packed_git *p,
1526 struct pack_window **w_curs,
c4001d92 1527 off_t *curpos,
2b87c45b 1528 unsigned long *sizep)
a733cb60 1529{
03e79c88
SP
1530 unsigned char *base;
1531 unsigned int left;
ad1ed5ee 1532 unsigned long used;
2b87c45b 1533 enum object_type type;
a733cb60 1534
8d8a4ea5 1535 /* use_pack() assures us we have [base, base + 20) available
0353a0c4 1536 * as a range that we can look at. (Its actually the hash
3dff5379 1537 * size that is assured.) With our object header encoding
8d8a4ea5
SP
1538 * the maximum deflated object size is 2^137, which is just
1539 * insane, so we know won't exceed what we have been given.
1540 */
2b87c45b 1541 base = use_pack(p, w_curs, *curpos, &left);
09ded04b
NP
1542 used = unpack_object_header_buffer(base, left, &type, sizep);
1543 if (!used) {
1544 type = OBJ_BAD;
1545 } else
1546 *curpos += used;
ad1ed5ee 1547
2b87c45b 1548 return type;
a733cb60
LT
1549}
1550
21666f1a 1551const char *packed_object_info_detail(struct packed_git *p,
c4001d92 1552 off_t obj_offset,
21666f1a
NP
1553 unsigned long *size,
1554 unsigned long *store_size,
1555 unsigned int *delta_chain_length,
1556 unsigned char *base_sha1)
ad8c80a5 1557{
03e79c88 1558 struct pack_window *w_curs = NULL;
c4001d92
SP
1559 off_t curpos;
1560 unsigned long dummy;
43057304 1561 unsigned char *next_sha1;
21666f1a 1562 enum object_type type;
70f5d5d3 1563 struct revindex_entry *revidx;
ad8c80a5 1564
43057304 1565 *delta_chain_length = 0;
2b87c45b 1566 curpos = obj_offset;
21666f1a 1567 type = unpack_object_header(p, &w_curs, &curpos, size);
43057304 1568
70f5d5d3
NP
1569 revidx = find_pack_revindex(p, obj_offset);
1570 *store_size = revidx[1].offset - obj_offset;
1571
43057304 1572 for (;;) {
21666f1a 1573 switch (type) {
43057304 1574 default:
08a19d87 1575 die("pack %s contains unknown object type %d",
21666f1a 1576 p->pack_name, type);
43057304
NP
1577 case OBJ_COMMIT:
1578 case OBJ_TREE:
1579 case OBJ_BLOB:
1580 case OBJ_TAG:
03e79c88 1581 unuse_pack(&w_curs);
21666f1a 1582 return typename(type);
eb32d236 1583 case OBJ_OFS_DELTA:
21666f1a 1584 obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
8eca0b47
NP
1585 if (!obj_offset)
1586 die("pack %s contains bad delta base reference of type %s",
1587 p->pack_name, typename(type));
eb32d236 1588 if (*delta_chain_length == 0) {
70f5d5d3
NP
1589 revidx = find_pack_revindex(p, obj_offset);
1590 hashcpy(base_sha1, nth_packed_object_sha1(p, revidx->nr));
eb32d236
NP
1591 }
1592 break;
1593 case OBJ_REF_DELTA:
2b87c45b 1594 next_sha1 = use_pack(p, &w_curs, curpos, NULL);
43057304
NP
1595 if (*delta_chain_length == 0)
1596 hashcpy(base_sha1, next_sha1);
2b87c45b 1597 obj_offset = find_pack_entry_one(next_sha1, p);
43057304
NP
1598 break;
1599 }
43057304 1600 (*delta_chain_length)++;
2b87c45b 1601 curpos = obj_offset;
21666f1a 1602 type = unpack_object_header(p, &w_curs, &curpos, &dummy);
ad8c80a5 1603 }
ad8c80a5
JH
1604}
1605
c4001d92 1606static int packed_object_info(struct packed_git *p, off_t obj_offset,
21666f1a 1607 unsigned long *sizep)
1f688557 1608{
03e79c88 1609 struct pack_window *w_curs = NULL;
c4001d92
SP
1610 unsigned long size;
1611 off_t curpos = obj_offset;
21666f1a 1612 enum object_type type;
5db47c2b 1613
21666f1a 1614 type = unpack_object_header(p, &w_curs, &curpos, &size);
5db47c2b 1615
21666f1a 1616 switch (type) {
eb32d236
NP
1617 case OBJ_OFS_DELTA:
1618 case OBJ_REF_DELTA:
21666f1a
NP
1619 type = packed_delta_info(p, &w_curs, curpos,
1620 type, obj_offset, sizep);
2b87c45b 1621 break;
a733cb60 1622 case OBJ_COMMIT:
a733cb60 1623 case OBJ_TREE:
a733cb60 1624 case OBJ_BLOB:
a733cb60 1625 case OBJ_TAG:
2b87c45b
NP
1626 if (sizep)
1627 *sizep = size;
a69d0943 1628 break;
1f688557 1629 default:
3d77d877
NP
1630 error("unknown object type %i at offset %"PRIuMAX" in %s",
1631 type, (uintmax_t)obj_offset, p->pack_name);
1632 type = OBJ_BAD;
1f688557 1633 }
2b87c45b 1634 unuse_pack(&w_curs);
21666f1a 1635 return type;
1f688557
JH
1636}
1637
eb950c19 1638static void *unpack_compressed_entry(struct packed_git *p,
03e79c88 1639 struct pack_window **w_curs,
c4001d92 1640 off_t curpos,
eb950c19 1641 unsigned long size)
de530aaa
SP
1642{
1643 int st;
1644 z_stream stream;
079afb18 1645 unsigned char *buffer, *in;
de530aaa 1646
4ab07e4d 1647 buffer = xmallocz(size);
de530aaa 1648 memset(&stream, 0, sizeof(stream));
de530aaa 1649 stream.next_out = buffer;
39eea7bd 1650 stream.avail_out = size + 1;
de530aaa 1651
39c68542 1652 git_inflate_init(&stream);
079afb18 1653 do {
2b87c45b 1654 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18 1655 stream.next_in = in;
39c68542 1656 st = git_inflate(&stream, Z_FINISH);
39eea7bd
JH
1657 if (!stream.avail_out)
1658 break; /* the payload is larger than it should be */
2b87c45b 1659 curpos += stream.next_in - in;
079afb18 1660 } while (st == Z_OK || st == Z_BUF_ERROR);
39c68542 1661 git_inflate_end(&stream);
de530aaa
SP
1662 if ((st != Z_STREAM_END) || stream.total_out != size) {
1663 free(buffer);
1664 return NULL;
1665 }
1666
1667 return buffer;
1668}
1669
e5e01619
LT
1670#define MAX_DELTA_CACHE (256)
1671
18bdec11 1672static size_t delta_base_cached;
5e08ecbf
NP
1673
1674static struct delta_base_cache_lru_list {
1675 struct delta_base_cache_lru_list *prev;
1676 struct delta_base_cache_lru_list *next;
1677} delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru };
1678
e5e01619 1679static struct delta_base_cache_entry {
5e08ecbf
NP
1680 struct delta_base_cache_lru_list lru;
1681 void *data;
e5e01619
LT
1682 struct packed_git *p;
1683 off_t base_offset;
1684 unsigned long size;
e5e01619
LT
1685 enum object_type type;
1686} delta_base_cache[MAX_DELTA_CACHE];
1687
1688static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
1689{
1690 unsigned long hash;
1691
1692 hash = (unsigned long)p + (unsigned long)base_offset;
1693 hash += (hash >> 8) + (hash >> 16);
3358004a 1694 return hash % MAX_DELTA_CACHE;
e5e01619
LT
1695}
1696
62f255ad 1697static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
a0cba108 1698 unsigned long *base_size, enum object_type *type, int keep_cache)
62f255ad 1699{
e5e01619
LT
1700 void *ret;
1701 unsigned long hash = pack_entry_hash(p, base_offset);
1702 struct delta_base_cache_entry *ent = delta_base_cache + hash;
1703
1704 ret = ent->data;
749bc58c
MV
1705 if (!ret || ent->p != p || ent->base_offset != base_offset)
1706 return unpack_entry(p, base_offset, type, base_size);
e5e01619 1707
18bdec11 1708 if (!keep_cache) {
a0cba108 1709 ent->data = NULL;
5e08ecbf
NP
1710 ent->lru.next->prev = ent->lru.prev;
1711 ent->lru.prev->next = ent->lru.next;
18bdec11 1712 delta_base_cached -= ent->size;
182af834
PH
1713 } else {
1714 ret = xmemdupz(ent->data, ent->size);
a0cba108 1715 }
e5e01619
LT
1716 *type = ent->type;
1717 *base_size = ent->size;
1718 return ret;
62f255ad
LT
1719}
1720
18bdec11
SP
1721static inline void release_delta_base_cache(struct delta_base_cache_entry *ent)
1722{
1723 if (ent->data) {
1724 free(ent->data);
1725 ent->data = NULL;
5e08ecbf
NP
1726 ent->lru.next->prev = ent->lru.prev;
1727 ent->lru.prev->next = ent->lru.next;
18bdec11
SP
1728 delta_base_cached -= ent->size;
1729 }
1730}
1731
3d20c636
SP
1732void clear_delta_base_cache(void)
1733{
1734 unsigned long p;
1735 for (p = 0; p < MAX_DELTA_CACHE; p++)
1736 release_delta_base_cache(&delta_base_cache[p]);
1737}
1738
62f255ad
LT
1739static void add_delta_base_cache(struct packed_git *p, off_t base_offset,
1740 void *base, unsigned long base_size, enum object_type type)
1741{
5e08ecbf 1742 unsigned long hash = pack_entry_hash(p, base_offset);
e5e01619 1743 struct delta_base_cache_entry *ent = delta_base_cache + hash;
5e08ecbf 1744 struct delta_base_cache_lru_list *lru;
e5e01619 1745
18bdec11
SP
1746 release_delta_base_cache(ent);
1747 delta_base_cached += base_size;
5e08ecbf
NP
1748
1749 for (lru = delta_base_cache_lru.next;
1750 delta_base_cached > delta_base_cache_limit
1751 && lru != &delta_base_cache_lru;
1752 lru = lru->next) {
1753 struct delta_base_cache_entry *f = (void *)lru;
18bdec11
SP
1754 if (f->type == OBJ_BLOB)
1755 release_delta_base_cache(f);
1756 }
5e08ecbf
NP
1757 for (lru = delta_base_cache_lru.next;
1758 delta_base_cached > delta_base_cache_limit
1759 && lru != &delta_base_cache_lru;
1760 lru = lru->next) {
1761 struct delta_base_cache_entry *f = (void *)lru;
1762 release_delta_base_cache(f);
1763 }
18bdec11 1764
e5e01619
LT
1765 ent->p = p;
1766 ent->base_offset = base_offset;
1767 ent->type = type;
1768 ent->data = base;
1769 ent->size = base_size;
5e08ecbf
NP
1770 ent->lru.next = &delta_base_cache_lru;
1771 ent->lru.prev = delta_base_cache_lru.prev;
1772 delta_base_cache_lru.prev->next = &ent->lru;
1773 delta_base_cache_lru.prev = &ent->lru;
62f255ad
LT
1774}
1775
c2c5b270
CC
1776static void *read_object(const unsigned char *sha1, enum object_type *type,
1777 unsigned long *size);
1778
eb950c19 1779static void *unpack_delta_entry(struct packed_git *p,
03e79c88 1780 struct pack_window **w_curs,
c4001d92 1781 off_t curpos,
1f688557 1782 unsigned long delta_size,
c4001d92 1783 off_t obj_offset,
21666f1a 1784 enum object_type *type,
eb950c19 1785 unsigned long *sizep)
1f688557 1786{
7c3e8be3 1787 void *delta_data, *result, *base;
c4001d92
SP
1788 unsigned long base_size;
1789 off_t base_offset;
43057304 1790
21666f1a 1791 base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
8eca0b47
NP
1792 if (!base_offset) {
1793 error("failed to validate delta base reference "
1794 "at offset %"PRIuMAX" from %s",
1795 (uintmax_t)curpos, p->pack_name);
1796 return NULL;
1797 }
eac12e2d 1798 unuse_pack(w_curs);
a0cba108 1799 base = cache_or_unpack_entry(p, base_offset, &base_size, type, 0);
8eca0b47
NP
1800 if (!base) {
1801 /*
1802 * We're probably in deep shit, but let's try to fetch
1803 * the required base anyway from another pack or loose.
1804 * This is costly but should happen only in the presence
1805 * of a corrupted pack, and is better than failing outright.
1806 */
08698b1e
NP
1807 struct revindex_entry *revidx;
1808 const unsigned char *base_sha1;
1809 revidx = find_pack_revindex(p, base_offset);
1810 if (!revidx)
1811 return NULL;
1812 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
8eca0b47
NP
1813 error("failed to read delta base object %s"
1814 " at offset %"PRIuMAX" from %s",
1815 sha1_to_hex(base_sha1), (uintmax_t)base_offset,
1816 p->pack_name);
1817 mark_bad_packed_object(p, base_sha1);
ac939109 1818 base = read_object(base_sha1, type, &base_size);
8eca0b47
NP
1819 if (!base)
1820 return NULL;
1821 }
67686d95 1822
2b87c45b 1823 delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size);
8eca0b47
NP
1824 if (!delta_data) {
1825 error("failed to unpack compressed delta "
1826 "at offset %"PRIuMAX" from %s",
1827 (uintmax_t)curpos, p->pack_name);
1828 free(base);
1829 return NULL;
1830 }
1f688557
JH
1831 result = patch_delta(base, base_size,
1832 delta_data, delta_size,
21666f1a 1833 sizep);
1f688557
JH
1834 if (!result)
1835 die("failed to apply delta");
1836 free(delta_data);
62f255ad 1837 add_delta_base_cache(p, base_offset, base, base_size, *type);
1f688557
JH
1838 return result;
1839}
1840
0e8189e2
NP
1841int do_check_packed_object_crc;
1842
c4001d92 1843void *unpack_entry(struct packed_git *p, off_t obj_offset,
21666f1a 1844 enum object_type *type, unsigned long *sizep)
1f688557 1845{
03e79c88 1846 struct pack_window *w_curs = NULL;
c4001d92 1847 off_t curpos = obj_offset;
21666f1a 1848 void *data;
1f688557 1849
0e8189e2
NP
1850 if (do_check_packed_object_crc && p->index_version > 1) {
1851 struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
1852 unsigned long len = revidx[1].offset - obj_offset;
1853 if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) {
1854 const unsigned char *sha1 =
1855 nth_packed_object_sha1(p, revidx->nr);
1856 error("bad packed object CRC for %s",
1857 sha1_to_hex(sha1));
1858 mark_bad_packed_object(p, sha1);
f755bb99 1859 unuse_pack(&w_curs);
0e8189e2
NP
1860 return NULL;
1861 }
1862 }
1863
21666f1a
NP
1864 *type = unpack_object_header(p, &w_curs, &curpos, sizep);
1865 switch (*type) {
eb32d236
NP
1866 case OBJ_OFS_DELTA:
1867 case OBJ_REF_DELTA:
21666f1a
NP
1868 data = unpack_delta_entry(p, &w_curs, curpos, *sizep,
1869 obj_offset, type, sizep);
4d703a1a 1870 break;
a733cb60 1871 case OBJ_COMMIT:
a733cb60 1872 case OBJ_TREE:
a733cb60 1873 case OBJ_BLOB:
a733cb60 1874 case OBJ_TAG:
21666f1a 1875 data = unpack_compressed_entry(p, &w_curs, curpos, *sizep);
4d703a1a 1876 break;
1f688557 1877 default:
8eca0b47
NP
1878 data = NULL;
1879 error("unknown object type %i at offset %"PRIuMAX" in %s",
1880 *type, (uintmax_t)obj_offset, p->pack_name);
1f688557 1881 }
03e79c88 1882 unuse_pack(&w_curs);
21666f1a 1883 return data;
1f688557
JH
1884}
1885
d079837e 1886const unsigned char *nth_packed_object_sha1(struct packed_git *p,
d72308e0 1887 uint32_t n)
9a217f2a 1888{
42873078 1889 const unsigned char *index = p->index_data;
d079837e
SP
1890 if (!index) {
1891 if (open_pack_index(p))
1892 return NULL;
1893 index = p->index_data;
1894 }
57059091 1895 if (n >= p->num_objects)
d72308e0 1896 return NULL;
74e34e1f
NP
1897 index += 4 * 256;
1898 if (p->index_version == 1) {
1899 return index + 24 * n + 4;
1900 } else {
1901 index += 8;
1902 return index + 20 * n;
1903 }
1904}
1905
99093238 1906off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
74e34e1f
NP
1907{
1908 const unsigned char *index = p->index_data;
1909 index += 4 * 256;
1910 if (p->index_version == 1) {
1911 return ntohl(*((uint32_t *)(index + 24 * n)));
1912 } else {
1913 uint32_t off;
1914 index += 8 + p->num_objects * (20 + 4);
1915 off = ntohl(*((uint32_t *)(index + 4 * n)));
1916 if (!(off & 0x80000000))
1917 return off;
1918 index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
1919 return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
1920 ntohl(*((uint32_t *)(index + 4)));
1921 }
9a217f2a
JH
1922}
1923
c4001d92 1924off_t find_pack_entry_one(const unsigned char *sha1,
43057304 1925 struct packed_git *p)
1f688557 1926{
42873078 1927 const uint32_t *level1_ofs = p->index_data;
42873078 1928 const unsigned char *index = p->index_data;
628522ec
JH
1929 unsigned hi, lo, stride;
1930 static int use_lookup = -1;
1931 static int debug_lookup = -1;
1932
1933 if (debug_lookup < 0)
1934 debug_lookup = !!getenv("GIT_DEBUG_LOOKUP");
42873078 1935
d079837e
SP
1936 if (!index) {
1937 if (open_pack_index(p))
1938 return 0;
1939 level1_ofs = p->index_data;
1940 index = p->index_data;
1941 }
74e34e1f
NP
1942 if (p->index_version > 1) {
1943 level1_ofs += 2;
1944 index += 8;
1945 }
42873078 1946 index += 4 * 256;
74e34e1f
NP
1947 hi = ntohl(level1_ofs[*sha1]);
1948 lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
628522ec
JH
1949 if (p->index_version > 1) {
1950 stride = 20;
1951 } else {
1952 stride = 24;
1953 index += 4;
1954 }
1955
1956 if (debug_lookup)
6e1c2344 1957 printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n",
628522ec
JH
1958 sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects);
1959
1960 if (use_lookup < 0)
1961 use_lookup = !!getenv("GIT_USE_LOOKUP");
1962 if (use_lookup) {
1963 int pos = sha1_entry_pos(index, stride, 0,
1964 lo, hi, p->num_objects, sha1);
1965 if (pos < 0)
1966 return 0;
1967 return nth_packed_object_offset(p, pos);
1968 }
1f688557
JH
1969
1970 do {
74e34e1f 1971 unsigned mi = (lo + hi) / 2;
628522ec
JH
1972 int cmp = hashcmp(index + mi * stride, sha1);
1973
1974 if (debug_lookup)
1975 printf("lo %u hi %u rg %u mi %u\n",
1976 lo, hi, hi - lo, mi);
43057304 1977 if (!cmp)
74e34e1f 1978 return nth_packed_object_offset(p, mi);
1f688557
JH
1979 if (cmp > 0)
1980 hi = mi;
1981 else
1982 lo = mi+1;
1983 } while (lo < hi);
1984 return 0;
1985}
1986
d131b7af
SP
1987static int is_pack_valid(struct packed_git *p)
1988{
1989 /* An already open pack is known to be valid. */
1990 if (p->pack_fd != -1)
1991 return 1;
1992
1993 /* If the pack has one window completely covering the
1994 * file size, the pack is known to be valid even if
1995 * the descriptor is not currently open.
1996 */
1997 if (p->windows) {
1998 struct pack_window *w = p->windows;
1999
2000 if (!w->offset && w->len == p->pack_size)
2001 return 1;
2002 }
2003
2004 /* Force the pack to open to prove its valid. */
2005 return !open_packed_git(p);
2006}
2007
4d6acb70 2008static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1f688557 2009{
f7c22cc6 2010 static struct packed_git *last_found = (void *)1;
1f688557 2011 struct packed_git *p;
c4001d92 2012 off_t offset;
43057304 2013
1f688557 2014 prepare_packed_git();
f7c22cc6
NP
2015 if (!packed_git)
2016 return 0;
2017 p = (last_found == (void *)1) ? packed_git : last_found;
1f688557 2018
f7c22cc6 2019 do {
8eca0b47
NP
2020 if (p->num_bad_objects) {
2021 unsigned i;
2022 for (i = 0; i < p->num_bad_objects; i++)
2023 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
2024 goto next;
2025 }
2026
43057304
NP
2027 offset = find_pack_entry_one(sha1, p);
2028 if (offset) {
c715f783
SP
2029 /*
2030 * We are about to tell the caller where they can
2031 * locate the requested object. We better make
2032 * sure the packfile is still here and can be
2033 * accessed before supplying that answer, as
2034 * it may have been deleted since the index
2035 * was loaded!
2036 */
d131b7af 2037 if (!is_pack_valid(p)) {
c715f783 2038 error("packfile %s cannot be accessed", p->pack_name);
f7c22cc6 2039 goto next;
c715f783 2040 }
43057304
NP
2041 e->offset = offset;
2042 e->p = p;
2043 hashcpy(e->sha1, sha1);
f7c22cc6 2044 last_found = p;
1f688557 2045 return 1;
43057304 2046 }
f7c22cc6
NP
2047
2048 next:
2049 if (p == last_found)
2050 p = packed_git;
2051 else
2052 p = p->next;
2053 if (p == last_found)
2054 p = p->next;
2055 } while (p);
1f688557
JH
2056 return 0;
2057}
2058
a6080a0a 2059struct packed_git *find_sha1_pack(const unsigned char *sha1,
bf592c50
DB
2060 struct packed_git *packs)
2061{
2062 struct packed_git *p;
bf592c50
DB
2063
2064 for (p = packs; p; p = p->next) {
43057304 2065 if (find_pack_entry_one(sha1, p))
bf592c50
DB
2066 return p;
2067 }
2068 return NULL;
21666f1a 2069
bf592c50
DB
2070}
2071
21666f1a 2072static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep)
65c2e0c3 2073{
36e4d74a 2074 int status;
65c2e0c3
JH
2075 unsigned long mapsize, size;
2076 void *map;
2077 z_stream stream;
d65a16f6 2078 char hdr[32];
65c2e0c3 2079
bb6b8e4f 2080 map = map_sha1_file(sha1, &mapsize);
f0df4ed5
JS
2081 if (!map)
2082 return error("unable to find %s", sha1_to_hex(sha1));
36e4d74a
JH
2083 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
2084 status = error("unable to unpack %s header",
2085 sha1_to_hex(sha1));
21666f1a 2086 else if ((status = parse_sha1_header(hdr, &size)) < 0)
36e4d74a 2087 status = error("unable to parse %s header", sha1_to_hex(sha1));
21666f1a
NP
2088 else if (sizep)
2089 *sizep = size;
39c68542 2090 git_inflate_end(&stream);
65c2e0c3
JH
2091 munmap(map, mapsize);
2092 return status;
2093}
2094
21666f1a 2095int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
f0df4ed5 2096{
c4d9986f 2097 struct cached_object *co;
f0df4ed5 2098 struct pack_entry e;
ddd63e64 2099 int status;
f0df4ed5 2100
c4d9986f
NTND
2101 co = find_cached_object(sha1);
2102 if (co) {
2103 if (sizep)
2104 *sizep = co->size;
2105 return co->type;
2106 }
2107
cd673c1f 2108 if (!find_pack_entry(sha1, &e)) {
ddd63e64
SG
2109 /* Most likely it's a loose object. */
2110 status = sha1_loose_object_info(sha1, sizep);
2111 if (status >= 0)
2112 return status;
2113
2114 /* Not a loose object; someone else may have just packed it. */
f0df4ed5 2115 reprepare_packed_git();
cd673c1f 2116 if (!find_pack_entry(sha1, &e))
ddd63e64 2117 return status;
f0df4ed5 2118 }
3d77d877
NP
2119
2120 status = packed_object_info(e.p, e.offset, sizep);
2121 if (status < 0) {
2122 mark_bad_packed_object(e.p, sha1);
2123 status = sha1_object_info(sha1, sizep);
2124 }
2125
2126 return status;
f0df4ed5
JS
2127}
2128
21666f1a
NP
2129static void *read_packed_sha1(const unsigned char *sha1,
2130 enum object_type *type, unsigned long *size)
1f688557
JH
2131{
2132 struct pack_entry e;
8eca0b47 2133 void *data;
1f688557 2134
cd673c1f 2135 if (!find_pack_entry(sha1, &e))
1f688557 2136 return NULL;
8eca0b47
NP
2137 data = cache_or_unpack_entry(e.p, e.offset, size, type, 1);
2138 if (!data) {
2139 /*
2140 * We're probably in deep shit, but let's try to fetch
2141 * the required object anyway from another pack or loose.
2142 * This should happen only in the presence of a corrupted
2143 * pack, and is better than failing outright.
2144 */
2145 error("failed to read object %s at offset %"PRIuMAX" from %s",
2146 sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name);
2147 mark_bad_packed_object(e.p, sha1);
ac939109 2148 data = read_object(sha1, type, size);
8eca0b47
NP
2149 }
2150 return data;
1f688557
JH
2151}
2152
21666f1a
NP
2153int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
2154 unsigned char *sha1)
d66b37bb
JH
2155{
2156 struct cached_object *co;
2157
21666f1a 2158 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
2159 if (has_sha1_file(sha1) || find_cached_object(sha1))
2160 return 0;
2161 if (cached_object_alloc <= cached_object_nr) {
2162 cached_object_alloc = alloc_nr(cached_object_alloc);
2163 cached_objects = xrealloc(cached_objects,
2164 sizeof(*cached_objects) *
2165 cached_object_alloc);
2166 }
2167 co = &cached_objects[cached_object_nr++];
2168 co->size = len;
21666f1a 2169 co->type = type;
efa13f7b
JH
2170 co->buf = xmalloc(len);
2171 memcpy(co->buf, buf, len);
d66b37bb
JH
2172 hashcpy(co->sha1, sha1);
2173 return 0;
2174}
2175
c2c5b270
CC
2176static void *read_object(const unsigned char *sha1, enum object_type *type,
2177 unsigned long *size)
0fcfd160
LT
2178{
2179 unsigned long mapsize;
2180 void *map, *buf;
d66b37bb
JH
2181 struct cached_object *co;
2182
2183 co = find_cached_object(sha1);
2184 if (co) {
21666f1a 2185 *type = co->type;
d66b37bb 2186 *size = co->size;
182af834 2187 return xmemdupz(co->buf, co->size);
d66b37bb 2188 }
0fcfd160 2189
8276c007
PE
2190 buf = read_packed_sha1(sha1, type, size);
2191 if (buf)
2192 return buf;
bb6b8e4f 2193 map = map_sha1_file(sha1, &mapsize);
0fcfd160 2194 if (map) {
7efbff75 2195 buf = unpack_sha1_file(map, mapsize, type, size, sha1);
0fcfd160
LT
2196 munmap(map, mapsize);
2197 return buf;
2198 }
637cdd9d 2199 reprepare_packed_git();
8276c007 2200 return read_packed_sha1(sha1, type, size);
0fcfd160
LT
2201}
2202
b6c4cecc
JH
2203/*
2204 * This function dies on corrupt objects; the callers who want to
2205 * deal with them should arrange to call read_object() and give error
2206 * messages themselves.
2207 */
f5552aee
CC
2208void *read_sha1_file_repl(const unsigned char *sha1,
2209 enum object_type *type,
2210 unsigned long *size,
2211 const unsigned char **replacement)
ac939109 2212{
68095570 2213 const unsigned char *repl = lookup_replace_object(sha1);
3ba7a065 2214 void *data;
e8b15e61 2215 char *path;
b6c4cecc
JH
2216 const struct packed_git *p;
2217
3ba7a065
JH
2218 errno = 0;
2219 data = read_object(repl, type, size);
b6c4cecc
JH
2220 if (data) {
2221 if (replacement)
2222 *replacement = repl;
2223 return data;
2224 }
68095570 2225
25f3af3f 2226 if (errno && errno != ENOENT)
3ba7a065
JH
2227 die_errno("failed to read object %s", sha1_to_hex(sha1));
2228
68095570 2229 /* die if we replaced an object with one that does not exist */
b6c4cecc 2230 if (repl != sha1)
68095570
CC
2231 die("replacement %s not found for %s",
2232 sha1_to_hex(repl), sha1_to_hex(sha1));
2233
b6c4cecc
JH
2234 if (has_loose_object(repl)) {
2235 path = sha1_file_name(sha1);
2236 die("loose object %s (stored in %s) is corrupt",
2237 sha1_to_hex(repl), path);
e8b15e61 2238 }
68095570 2239
b6c4cecc
JH
2240 if ((p = has_packed_and_bad(repl)) != NULL)
2241 die("packed object %s (stored in %s) is corrupt",
2242 sha1_to_hex(repl), p->pack_name);
f5552aee 2243
b6c4cecc 2244 return NULL;
ac939109
NP
2245}
2246
40469ee9 2247void *read_object_with_reference(const unsigned char *sha1,
21666f1a 2248 const char *required_type_name,
40469ee9
JH
2249 unsigned long *size,
2250 unsigned char *actual_sha1_return)
f4913f91 2251{
21666f1a 2252 enum object_type type, required_type;
f4913f91
JH
2253 void *buffer;
2254 unsigned long isize;
40469ee9 2255 unsigned char actual_sha1[20];
f4913f91 2256
21666f1a 2257 required_type = type_from_string(required_type_name);
e702496e 2258 hashcpy(actual_sha1, sha1);
40469ee9
JH
2259 while (1) {
2260 int ref_length = -1;
2261 const char *ref_type = NULL;
f4913f91 2262
21666f1a 2263 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
2264 if (!buffer)
2265 return NULL;
21666f1a 2266 if (type == required_type) {
40469ee9
JH
2267 *size = isize;
2268 if (actual_sha1_return)
e702496e 2269 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
2270 return buffer;
2271 }
2272 /* Handle references */
21666f1a 2273 else if (type == OBJ_COMMIT)
40469ee9 2274 ref_type = "tree ";
21666f1a 2275 else if (type == OBJ_TAG)
40469ee9
JH
2276 ref_type = "object ";
2277 else {
2278 free(buffer);
2279 return NULL;
2280 }
2281 ref_length = strlen(ref_type);
f4913f91 2282
50974ec9
MK
2283 if (ref_length + 40 > isize ||
2284 memcmp(buffer, ref_type, ref_length) ||
1d7f171c 2285 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
2286 free(buffer);
2287 return NULL;
2288 }
1cf58e72 2289 free(buffer);
40469ee9
JH
2290 /* Now we have the ID of the referred-to object in
2291 * actual_sha1. Check again. */
f4913f91 2292 }
f4913f91
JH
2293}
2294
ce9fbf16 2295static void write_sha1_file_prepare(const void *buf, unsigned long len,
972a9155 2296 const char *type, unsigned char *sha1,
d65a16f6 2297 char *hdr, int *hdrlen)
d410c0f5 2298{
9126f009 2299 git_SHA_CTX c;
d410c0f5
JH
2300
2301 /* Generate the header */
d65a16f6 2302 *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
d410c0f5
JH
2303
2304 /* Sha1.. */
9126f009
NP
2305 git_SHA1_Init(&c);
2306 git_SHA1_Update(&c, hdr, *hdrlen);
2307 git_SHA1_Update(&c, buf, len);
2308 git_SHA1_Final(sha1, &c);
d410c0f5
JH
2309}
2310
230f1322 2311/*
5a688fe4
JH
2312 * Move the just written object into its final resting place.
2313 * NEEDSWORK: this should be renamed to finalize_temp_file() as
2314 * "moving" is only a part of what it does, when no patch between
2315 * master to pu changes the call sites of this function.
230f1322 2316 */
839837b9 2317int move_temp_to_file(const char *tmpfile, const char *filename)
230f1322 2318{
e32c0a9c 2319 int ret = 0;
5a688fe4 2320
348df166 2321 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
be66a6c4
JS
2322 goto try_rename;
2323 else if (link(tmpfile, filename))
e32c0a9c 2324 ret = errno;
7ebb6fca
LT
2325
2326 /*
2327 * Coda hack - coda doesn't like cross-directory links,
2328 * so we fall back to a rename, which will mean that it
2329 * won't be able to check collisions, but that's not a
2330 * big deal.
2331 *
2332 * The same holds for FAT formatted media.
2333 *
3be1f18e 2334 * When this succeeds, we just return. We have nothing
7ebb6fca
LT
2335 * left to unlink.
2336 */
2337 if (ret && ret != EEXIST) {
be66a6c4 2338 try_rename:
7ebb6fca 2339 if (!rename(tmpfile, filename))
3be1f18e 2340 goto out;
9e48b389 2341 ret = errno;
230f1322 2342 }
691f1a28 2343 unlink_or_warn(tmpfile);
230f1322
LT
2344 if (ret) {
2345 if (ret != EEXIST) {
916d081b 2346 return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret));
230f1322
LT
2347 }
2348 /* FIXME!!! Collision check here ? */
2349 }
2350
3be1f18e 2351out:
5256b006 2352 if (adjust_shared_perm(filename))
5a688fe4 2353 return error("unable to set permission to '%s'", filename);
230f1322
LT
2354 return 0;
2355}
2356
4d548150
LT
2357static int write_buffer(int fd, const void *buf, size_t len)
2358{
d34cf19b 2359 if (write_in_full(fd, buf, len) < 0)
93822c22 2360 return error("file write error (%s)", strerror(errno));
4d548150
LT
2361 return 0;
2362}
2363
ce9fbf16 2364int hash_sha1_file(const void *buf, unsigned long len, const char *type,
abdc3fc8
RS
2365 unsigned char *sha1)
2366{
d65a16f6 2367 char hdr[32];
abdc3fc8
RS
2368 int hdrlen;
2369 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2370 return 0;
2371}
2372
e9039dd3
LT
2373/* Finalize a file on disk, and close it. */
2374static void close_sha1_file(int fd)
2375{
aafe9fba
LT
2376 if (fsync_object_files)
2377 fsync_or_die(fd, "sha1 file");
e9039dd3 2378 if (close(fd) != 0)
d824cbba 2379 die_errno("error when closing sha1 file");
e9039dd3
LT
2380}
2381
5723fe7e
LT
2382/* Size of directory component, including the ending '/' */
2383static inline int directory_size(const char *filename)
2384{
2385 const char *s = strrchr(filename, '/');
2386 if (!s)
2387 return 0;
2388 return s - filename + 1;
2389}
2390
2391/*
2392 * This creates a temporary file in the same directory as the final
2393 * 'filename'
2394 *
2395 * We want to avoid cross-directory filename renames, because those
2396 * can have problems on various filesystems (FAT, NFS, Coda).
2397 */
2398static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename)
2399{
2400 int fd, dirlen = directory_size(filename);
2401
2402 if (dirlen + 20 > bufsiz) {
2403 errno = ENAMETOOLONG;
2404 return -1;
2405 }
2406 memcpy(buffer, filename, dirlen);
2407 strcpy(buffer + dirlen, "tmp_obj_XXXXXX");
5256b006 2408 fd = git_mkstemp_mode(buffer, 0444);
cbacbf4e 2409 if (fd < 0 && dirlen && errno == ENOENT) {
5723fe7e 2410 /* Make sure the directory exists */
6ff6af62 2411 memcpy(buffer, filename, dirlen);
5723fe7e 2412 buffer[dirlen-1] = 0;
3bfaf018 2413 if (mkdir(buffer, 0777) || adjust_shared_perm(buffer))
5723fe7e
LT
2414 return -1;
2415
2416 /* Try again */
2417 strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX");
5256b006 2418 fd = git_mkstemp_mode(buffer, 0444);
5723fe7e
LT
2419 }
2420 return fd;
2421}
2422
bbac7311 2423static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
c00e657d 2424 const void *buf, unsigned long len, time_t mtime)
0fcfd160 2425{
915308b1 2426 int fd, ret;
9892beba 2427 unsigned char compressed[4096];
0fcfd160 2428 z_stream stream;
748af44c
NP
2429 git_SHA_CTX c;
2430 unsigned char parano_sha1[20];
706bc531 2431 char *filename;
aac17941 2432 static char tmpfile[PATH_MAX];
a44c9a5e 2433
972a9155 2434 filename = sha1_file_name(sha1);
5723fe7e 2435 fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename);
aac17941 2436 if (fd < 0) {
35243577 2437 if (errno == EACCES)
916d081b
PB
2438 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
2439 else
2440 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
aac17941
LT
2441 }
2442
0fcfd160
LT
2443 /* Set it up */
2444 memset(&stream, 0, sizeof(stream));
55bb5c91 2445 git_deflate_init(&stream, zlib_compression_level);
0fcfd160 2446 stream.next_out = compressed;
9892beba 2447 stream.avail_out = sizeof(compressed);
748af44c 2448 git_SHA1_Init(&c);
a44c9a5e
LT
2449
2450 /* First header.. */
d65a16f6 2451 stream.next_in = (unsigned char *)hdr;
a44c9a5e 2452 stream.avail_in = hdrlen;
55bb5c91
JH
2453 while (git_deflate(&stream, 0) == Z_OK)
2454 ; /* nothing */
748af44c 2455 git_SHA1_Update(&c, hdr, hdrlen);
a44c9a5e
LT
2456
2457 /* Then the data itself.. */
c00e657d 2458 stream.next_in = (void *)buf;
a44c9a5e 2459 stream.avail_in = len;
9892beba 2460 do {
748af44c 2461 unsigned char *in0 = stream.next_in;
55bb5c91 2462 ret = git_deflate(&stream, Z_FINISH);
748af44c 2463 git_SHA1_Update(&c, in0, stream.next_in - in0);
9892beba
NP
2464 if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
2465 die("unable to write sha1 file");
2466 stream.next_out = compressed;
2467 stream.avail_out = sizeof(compressed);
2468 } while (ret == Z_OK);
2469
ac54c277
LT
2470 if (ret != Z_STREAM_END)
2471 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
55bb5c91 2472 ret = git_deflate_end_gently(&stream);
ac54c277
LT
2473 if (ret != Z_OK)
2474 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
748af44c
NP
2475 git_SHA1_Final(parano_sha1, &c);
2476 if (hashcmp(sha1, parano_sha1) != 0)
2477 die("confused by unstable object source data for %s", sha1_to_hex(sha1));
ac54c277 2478
e9039dd3 2479 close_sha1_file(fd);
0fcfd160 2480
bbac7311
NP
2481 if (mtime) {
2482 struct utimbuf utb;
2483 utb.actime = mtime;
2484 utb.modtime = mtime;
2485 if (utime(tmpfile, &utb) < 0)
2486 warning("failed utime() on %s: %s",
2487 tmpfile, strerror(errno));
2488 }
2489
230f1322 2490 return move_temp_to_file(tmpfile, filename);
0fcfd160 2491}
8237b185 2492
c00e657d 2493int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
bbac7311
NP
2494{
2495 unsigned char sha1[20];
2496 char hdr[32];
2497 int hdrlen;
2498
2499 /* Normally if we have it in the pack then we do not bother writing
2500 * it out into .git/objects/??/?{38} file.
2501 */
2502 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2503 if (returnsha1)
2504 hashcpy(returnsha1, sha1);
2505 if (has_sha1_file(sha1))
2506 return 0;
2507 return write_loose_object(sha1, hdr, hdrlen, buf, len, 0);
2508}
2509
2510int force_object_loose(const unsigned char *sha1, time_t mtime)
2511{
bbac7311
NP
2512 void *buf;
2513 unsigned long len;
2514 enum object_type type;
2515 char hdr[32];
2516 int hdrlen;
1fb23e65 2517 int ret;
bbac7311 2518
c529d75a 2519 if (has_loose_object(sha1))
bbac7311
NP
2520 return 0;
2521 buf = read_packed_sha1(sha1, &type, &len);
2522 if (!buf)
2523 return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
2524 hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
1fb23e65
BS
2525 ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
2526 free(buf);
2527
2528 return ret;
bbac7311
NP
2529}
2530
bf592c50
DB
2531int has_pack_index(const unsigned char *sha1)
2532{
2533 struct stat st;
2534 if (stat(sha1_pack_index_name(sha1), &st))
2535 return 0;
2536 return 1;
bf592c50
DB
2537}
2538
cd673c1f
JH
2539int has_sha1_pack(const unsigned char *sha1)
2540{
2541 struct pack_entry e;
2542 return find_pack_entry(sha1, &e);
2543}
2544
8237b185
DB
2545int has_sha1_file(const unsigned char *sha1)
2546{
1f688557
JH
2547 struct pack_entry e;
2548
cd673c1f 2549 if (find_pack_entry(sha1, &e))
1f688557 2550 return 1;
c529d75a 2551 return has_loose_object(sha1);
8237b185 2552}
74400e71 2553
c879daa2
NTND
2554static void check_tree(const void *buf, size_t size)
2555{
2556 struct tree_desc desc;
2557 struct name_entry entry;
2558
2559 init_tree_desc(&desc, buf, size);
2560 while (tree_entry(&desc, &entry))
2561 /* do nothing
2562 * tree_entry() will die() on malformed entries */
2563 ;
2564}
2565
2566static void check_commit(const void *buf, size_t size)
2567{
2568 struct commit c;
2569 memset(&c, 0, sizeof(c));
2570 if (parse_commit_buffer(&c, buf, size))
2571 die("corrupt commit");
2572}
2573
2574static void check_tag(const void *buf, size_t size)
2575{
2576 struct tag t;
2577 memset(&t, 0, sizeof(t));
2578 if (parse_tag_buffer(&t, buf, size))
2579 die("corrupt tag");
2580}
2581
43df4f86 2582static int index_mem(unsigned char *sha1, void *buf, size_t size,
c879daa2
NTND
2583 int write_object, enum object_type type,
2584 const char *path, int format_check)
e7332f96 2585{
6c510bee 2586 int ret, re_allocated = 0;
74400e71 2587
7672db20 2588 if (!type)
edaec3fb 2589 type = OBJ_BLOB;
6c510bee
LT
2590
2591 /*
2592 * Convert blobs to git internal format
2593 */
43df4f86 2594 if ((type == OBJ_BLOB) && path) {
f285a2d7 2595 struct strbuf nbuf = STRBUF_INIT;
21e5ad50
SP
2596 if (convert_to_git(path, buf, size, &nbuf,
2597 write_object ? safe_crlf : 0)) {
b315c5c0 2598 buf = strbuf_detach(&nbuf, &size);
6c510bee
LT
2599 re_allocated = 1;
2600 }
2601 }
c879daa2
NTND
2602 if (format_check) {
2603 if (type == OBJ_TREE)
2604 check_tree(buf, size);
2605 if (type == OBJ_COMMIT)
2606 check_commit(buf, size);
2607 if (type == OBJ_TAG)
2608 check_tag(buf, size);
2609 }
6c510bee 2610
7672db20 2611 if (write_object)
edaec3fb 2612 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 2613 else
edaec3fb 2614 ret = hash_sha1_file(buf, size, typename(type), sha1);
43df4f86 2615 if (re_allocated)
6c510bee 2616 free(buf);
43df4f86
DP
2617 return ret;
2618}
2619
ea68b0ce
DP
2620#define SMALL_FILE_SIZE (32*1024)
2621
43df4f86 2622int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object,
c879daa2 2623 enum object_type type, const char *path, int format_check)
43df4f86
DP
2624{
2625 int ret;
2626 size_t size = xsize_t(st->st_size);
2627
2628 if (!S_ISREG(st->st_mode)) {
f285a2d7 2629 struct strbuf sbuf = STRBUF_INIT;
43df4f86
DP
2630 if (strbuf_read(&sbuf, fd, 4096) >= 0)
2631 ret = index_mem(sha1, sbuf.buf, sbuf.len, write_object,
c879daa2 2632 type, path, format_check);
43df4f86
DP
2633 else
2634 ret = -1;
2635 strbuf_release(&sbuf);
08bda208 2636 } else if (!size) {
c879daa2
NTND
2637 ret = index_mem(sha1, NULL, size, write_object, type, path,
2638 format_check);
ea68b0ce
DP
2639 } else if (size <= SMALL_FILE_SIZE) {
2640 char *buf = xmalloc(size);
2641 if (size == read_in_full(fd, buf, size))
2642 ret = index_mem(sha1, buf, size, write_object, type,
c879daa2 2643 path, format_check);
ea68b0ce
DP
2644 else
2645 ret = error("short read %s", strerror(errno));
2646 free(buf);
08bda208 2647 } else {
43df4f86 2648 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
c879daa2
NTND
2649 ret = index_mem(sha1, buf, size, write_object, type, path,
2650 format_check);
aac17941 2651 munmap(buf, size);
08bda208 2652 }
43df4f86 2653 close(fd);
aac17941 2654 return ret;
74400e71 2655}
ec1fcc16
JH
2656
2657int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
2658{
2659 int fd;
b760d3aa 2660 struct strbuf sb = STRBUF_INIT;
ec1fcc16
JH
2661
2662 switch (st->st_mode & S_IFMT) {
2663 case S_IFREG:
2664 fd = open(path, O_RDONLY);
2665 if (fd < 0)
2666 return error("open(\"%s\"): %s", path,
2667 strerror(errno));
c879daa2 2668 if (index_fd(sha1, fd, st, write_object, OBJ_BLOB, path, 0) < 0)
ec1fcc16
JH
2669 return error("%s: failed to insert into database",
2670 path);
2671 break;
2672 case S_IFLNK:
b760d3aa 2673 if (strbuf_readlink(&sb, path, st->st_size)) {
ec1fcc16 2674 char *errstr = strerror(errno);
ec1fcc16
JH
2675 return error("readlink(\"%s\"): %s", path,
2676 errstr);
2677 }
abdc3fc8 2678 if (!write_object)
b760d3aa
LT
2679 hash_sha1_file(sb.buf, sb.len, blob_type, sha1);
2680 else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1))
ec1fcc16
JH
2681 return error("%s: failed to insert into database",
2682 path);
b760d3aa 2683 strbuf_release(&sb);
ec1fcc16 2684 break;
f35a6d3b
LT
2685 case S_IFDIR:
2686 return resolve_gitlink_ref(path, "HEAD", sha1);
ec1fcc16
JH
2687 default:
2688 return error("%s: unsupported file type", path);
2689 }
2690 return 0;
2691}
a69e5429
JH
2692
2693int read_pack_header(int fd, struct pack_header *header)
2694{
c697ad14
HO
2695 if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header))
2696 /* "eof before pack header was fully read" */
2697 return PH_ERROR_EOF;
2698
a69e5429
JH
2699 if (header->hdr_signature != htonl(PACK_SIGNATURE))
2700 /* "protocol error (pack signature mismatch detected)" */
2701 return PH_ERROR_PACK_SIGNATURE;
2702 if (!pack_version_ok(header->hdr_version))
2703 /* "protocol error (pack version unsupported)" */
2704 return PH_ERROR_PROTOCOL;
2705 return 0;
2706}
40d52ff7
JK
2707
2708void assert_sha1_type(const unsigned char *sha1, enum object_type expect)
2709{
2710 enum object_type type = sha1_object_info(sha1, NULL);
2711 if (type < 0)
2712 die("%s is not a valid object", sha1_to_hex(sha1));
2713 if (type != expect)
2714 die("%s is not a valid '%s' object", sha1_to_hex(sha1),
2715 typename(expect));
2716}