config.c: fix mmap leak when writing config
[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"
6eac50d8 10#include "string-list.h"
697cc8ef 11#include "lockfile.h"
1f688557 12#include "delta.h"
a733cb60 13#include "pack.h"
8e440259
PE
14#include "blob.h"
15#include "commit.h"
4dd1fbc7 16#include "run-command.h"
8e440259
PE
17#include "tag.h"
18#include "tree.h"
c879daa2 19#include "tree-walk.h"
f35a6d3b 20#include "refs.h"
70f5d5d3 21#include "pack-revindex.h"
628522ec 22#include "sha1-lookup.h"
568508e7 23#include "bulk-checkin.h"
090ea126 24#include "streaming.h"
543c5caa 25#include "dir.h"
0fcfd160 26
144bde78
LT
27#ifndef O_NOATIME
28#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
29#define O_NOATIME 01000000
30#else
31#define O_NOATIME 0
32#endif
33#endif
34
28bd70d8
JN
35#define SZ_FMT PRIuMAX
36static inline uintmax_t sz_fmt(size_t s) { return s; }
e05db0fd 37
96f1e58f 38const unsigned char null_sha1[20];
88cd621d 39
c597ba80
NTND
40/*
41 * This is meant to hold a *small* number of objects that you would
42 * want read_sha1_file() to be able to return, but yet you do not want
43 * to write them into the object store (e.g. a browse-only
44 * application).
45 */
46static struct cached_object {
47 unsigned char sha1[20];
48 enum object_type type;
49 void *buf;
50 unsigned long size;
51} *cached_objects;
52static int cached_object_nr, cached_object_alloc;
53
54static struct cached_object empty_tree = {
dab0d410 55 EMPTY_TREE_SHA1_BIN_LITERAL,
c597ba80
NTND
56 OBJ_TREE,
57 "",
58 0
59};
60
1b1005d1
MH
61/*
62 * A pointer to the last packed_git in which an object was found.
63 * When an object is sought, we look in this packfile first, because
64 * objects that are looked up at similar times are often in the same
65 * packfile as one another.
66 */
c01f51cc
NTND
67static struct packed_git *last_found_pack;
68
c597ba80
NTND
69static struct cached_object *find_cached_object(const unsigned char *sha1)
70{
71 int i;
72 struct cached_object *co = cached_objects;
73
74 for (i = 0; i < cached_object_nr; i++, co++) {
75 if (!hashcmp(co->sha1, sha1))
76 return co;
77 }
78 if (!hashcmp(sha1, empty_tree.sha1))
79 return &empty_tree;
80 return NULL;
81}
82
90a6464b
JH
83int mkdir_in_gitdir(const char *path)
84{
85 if (mkdir(path, 0777)) {
86 int saved_errno = errno;
87 struct stat st;
88 struct strbuf sb = STRBUF_INIT;
89
90 if (errno != EEXIST)
91 return -1;
92 /*
93 * Are we looking at a path in a symlinked worktree
94 * whose original repository does not yet have it?
95 * e.g. .git/rr-cache pointing at its original
96 * repository in which the user hasn't performed any
97 * conflict resolution yet?
98 */
99 if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
100 strbuf_readlink(&sb, path, st.st_size) ||
101 !is_absolute_path(sb.buf) ||
102 mkdir(sb.buf, 0777)) {
103 strbuf_release(&sb);
104 errno = saved_errno;
105 return -1;
106 }
107 strbuf_release(&sb);
108 }
109 return adjust_shared_perm(path);
110}
111
0be0521b 112enum scld_error safe_create_leading_directories(char *path)
b2cb9425 113{
26c8ae2a 114 char *next_component = path + offset_1st_component(path);
0be0521b 115 enum scld_error ret = SCLD_OK;
67d42212 116
0be0521b 117 while (ret == SCLD_OK && next_component) {
f0502332 118 struct stat st;
0f527403 119 char *slash = next_component, slash_character;
f0502332 120
0f527403
MH
121 while (*slash && !is_dir_sep(*slash))
122 slash++;
123
124 if (!*slash)
b2cb9425 125 break;
bf10cf70 126
26c8ae2a 127 next_component = slash + 1;
0f527403 128 while (is_dir_sep(*next_component))
bf10cf70 129 next_component++;
26c8ae2a 130 if (!*next_component)
5f0bdf50 131 break;
831651fd 132
0f527403 133 slash_character = *slash;
831651fd 134 *slash = '\0';
67d42212
JR
135 if (!stat(path, &st)) {
136 /* path exists */
9e6f885d 137 if (!S_ISDIR(st.st_mode))
0be0521b 138 ret = SCLD_EXISTS;
53a39721 139 } else if (mkdir(path, 0777)) {
928734d9 140 if (errno == EEXIST &&
9e6f885d 141 !stat(path, &st) && S_ISDIR(st.st_mode))
928734d9 142 ; /* somebody created it since we checked */
18d37e86
MH
143 else if (errno == ENOENT)
144 /*
145 * Either mkdir() failed because
146 * somebody just pruned the containing
147 * directory, or stat() failed because
148 * the file that was in our way was
149 * just removed. Either way, inform
150 * the caller that it might be worth
151 * trying again:
152 */
153 ret = SCLD_VANISHED;
9e6f885d 154 else
0be0521b 155 ret = SCLD_FAILED;
53a39721 156 } else if (adjust_shared_perm(path)) {
0be0521b 157 ret = SCLD_PERMS;
457f06d6 158 }
0f527403 159 *slash = slash_character;
b2cb9425 160 }
9e6f885d 161 return ret;
b2cb9425 162}
723c31fe 163
0be0521b 164enum scld_error safe_create_leading_directories_const(const char *path)
8e21d63b
JK
165{
166 /* path points to cache entries, so xstrdup before messing with it */
167 char *buf = xstrdup(path);
0be0521b 168 enum scld_error result = safe_create_leading_directories(buf);
8e21d63b
JK
169 free(buf);
170 return result;
171}
172
ace1534d
JH
173static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
174{
175 int i;
176 for (i = 0; i < 20; i++) {
177 static char hex[] = "0123456789abcdef";
178 unsigned int val = sha1[i];
179 char *pos = pathbuf + i*2 + (i > 0);
180 *pos++ = hex[val >> 4];
181 *pos = hex[val & 0xf];
182 }
183}
184
30d6c6ea 185const char *sha1_file_name(const unsigned char *sha1)
0fcfd160 186{
560fb6a1
JK
187 static char buf[PATH_MAX];
188 const char *objdir;
189 int len;
0fcfd160 190
560fb6a1
JK
191 objdir = get_object_directory();
192 len = strlen(objdir);
193
194 /* '/' + sha1(2) + '/' + sha1(38) + '\0' */
195 if (len + 43 > PATH_MAX)
196 die("insanely long object directory %s", objdir);
197 memcpy(buf, objdir, len);
198 buf[len] = '/';
199 buf[len+3] = '/';
200 buf[len+42] = '\0';
201 fill_sha1_path(buf + len + 1, sha1);
202 return buf;
0fcfd160
LT
203}
204
d40d535b
MH
205/*
206 * Return the name of the pack or index file with the specified sha1
207 * in its filename. *base and *name are scratch space that must be
208 * provided by the caller. which should be "pack" or "idx".
209 */
633f43e1 210static char *sha1_get_pack_name(const unsigned char *sha1,
6eec46bd 211 char **name, char **base, const char *which)
bf592c50
DB
212{
213 static const char hex[] = "0123456789abcdef";
633f43e1 214 char *buf;
bf592c50
DB
215 int i;
216
633f43e1 217 if (!*base) {
bf592c50
DB
218 const char *sha1_file_directory = get_object_directory();
219 int len = strlen(sha1_file_directory);
633f43e1 220 *base = xmalloc(len + 60);
6eec46bd
JH
221 sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
222 sha1_file_directory, which);
633f43e1 223 *name = *base + len + 11;
bf592c50
DB
224 }
225
633f43e1 226 buf = *name;
bf592c50
DB
227
228 for (i = 0; i < 20; i++) {
229 unsigned int val = *sha1++;
230 *buf++ = hex[val >> 4];
231 *buf++ = hex[val & 0xf];
232 }
a6080a0a 233
633f43e1 234 return *base;
bf592c50
DB
235}
236
633f43e1 237char *sha1_pack_name(const unsigned char *sha1)
bf592c50 238{
633f43e1 239 static char *name, *base;
bf592c50 240
6eec46bd 241 return sha1_get_pack_name(sha1, &name, &base, "pack");
633f43e1 242}
bf592c50 243
633f43e1
HO
244char *sha1_pack_index_name(const unsigned char *sha1)
245{
246 static char *name, *base;
a6080a0a 247
6eec46bd 248 return sha1_get_pack_name(sha1, &name, &base, "idx");
bf592c50
DB
249}
250
d5a63b99
JH
251struct alternate_object_database *alt_odb_list;
252static struct alternate_object_database **alt_odb_tail;
ace1534d 253
ddd5d056
JH
254/*
255 * Prepare alternate object database registry.
d5a63b99
JH
256 *
257 * The variable alt_odb_list points at the list of struct
258 * alternate_object_database. The elements on this list come from
259 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
260 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
261 * whose contents is similar to that environment variable but can be
262 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
263 * contains "/the/directory/corresponding/to/.git/objects/...", while
264 * its name points just after the slash at the end of ".git/objects/"
265 * in the example above, and has enough space to hold 40-byte hex
266 * SHA1, an extra slash for the first level indirection, and the
267 * terminating NUL.
ddd5d056 268 */
539e7506
EK
269static int link_alt_odb_entry(const char *entry, const char *relative_base,
270 int depth, const char *normalized_objdir)
ace1534d 271{
c2f493a4
MW
272 struct alternate_object_database *ent;
273 struct alternate_object_database *alt;
5bdf0a84
HW
274 int pfxlen, entlen;
275 struct strbuf pathbuf = STRBUF_INIT;
d5a63b99 276
85dadc38 277 if (!is_absolute_path(entry) && relative_base) {
5bdf0a84
HW
278 strbuf_addstr(&pathbuf, real_path(relative_base));
279 strbuf_addch(&pathbuf, '/');
c2f493a4 280 }
6eac50d8 281 strbuf_addstr(&pathbuf, entry);
c2f493a4 282
5bdf0a84
HW
283 normalize_path_copy(pathbuf.buf, pathbuf.buf);
284
285 pfxlen = strlen(pathbuf.buf);
286
287 /*
288 * The trailing slash after the directory name is given by
289 * this function at the end. Remove duplicates.
290 */
291 while (pfxlen && pathbuf.buf[pfxlen-1] == '/')
292 pfxlen -= 1;
293
294 entlen = pfxlen + 43; /* '/' + 2 hex + '/' + 38 hex + NUL */
295 ent = xmalloc(sizeof(*ent) + entlen);
296 memcpy(ent->base, pathbuf.buf, pfxlen);
297 strbuf_release(&pathbuf);
c2f493a4
MW
298
299 ent->name = ent->base + pfxlen + 1;
300 ent->base[pfxlen + 3] = '/';
301 ent->base[pfxlen] = ent->base[entlen-1] = 0;
302
303 /* Detect cases where alternate disappeared */
90b4a71c 304 if (!is_directory(ent->base)) {
c2f493a4
MW
305 error("object directory %s does not exist; "
306 "check .git/objects/info/alternates.",
307 ent->base);
308 free(ent);
309 return -1;
310 }
311
312 /* Prevent the common mistake of listing the same
313 * thing twice, or object directory itself.
314 */
315 for (alt = alt_odb_list; alt; alt = alt->next) {
80b47854
RS
316 if (pfxlen == alt->name - alt->base - 1 &&
317 !memcmp(ent->base, alt->base, pfxlen)) {
c2f493a4
MW
318 free(ent);
319 return -1;
320 }
321 }
539e7506 322 if (!strcmp_icase(ent->base, normalized_objdir)) {
c2f493a4
MW
323 free(ent);
324 return -1;
325 }
326
327 /* add the alternate entry */
328 *alt_odb_tail = ent;
329 alt_odb_tail = &(ent->next);
330 ent->next = NULL;
331
332 /* recursively add alternates */
333 read_info_alternates(ent->base, depth + 1);
334
335 ent->base[pfxlen] = '/';
336
337 return 0;
338}
339
c5950164 340static void link_alt_odb_entries(const char *alt, int len, int sep,
c2f493a4
MW
341 const char *relative_base, int depth)
342{
6eac50d8
MH
343 struct string_list entries = STRING_LIST_INIT_NODUP;
344 char *alt_copy;
345 int i;
539e7506 346 struct strbuf objdirbuf = STRBUF_INIT;
c2f493a4
MW
347
348 if (depth > 5) {
349 error("%s: ignoring alternate object stores, nesting too deep.",
350 relative_base);
351 return;
352 }
353
f655651e 354 strbuf_add_absolute_path(&objdirbuf, get_object_directory());
539e7506
EK
355 normalize_path_copy(objdirbuf.buf, objdirbuf.buf);
356
c5950164 357 alt_copy = xmemdupz(alt, len);
6eac50d8
MH
358 string_list_split_in_place(&entries, alt_copy, sep, -1);
359 for (i = 0; i < entries.nr; i++) {
360 const char *entry = entries.items[i].string;
361 if (entry[0] == '\0' || entry[0] == '#')
9577e7e3 362 continue;
6eac50d8
MH
363 if (!is_absolute_path(entry) && depth) {
364 error("%s: ignoring relative alternate object store %s",
365 relative_base, entry);
366 } else {
539e7506 367 link_alt_odb_entry(entry, relative_base, depth, objdirbuf.buf);
9577e7e3 368 }
9577e7e3 369 }
6eac50d8
MH
370 string_list_clear(&entries, 0);
371 free(alt_copy);
539e7506 372 strbuf_release(&objdirbuf);
d5a63b99
JH
373}
374
5e73633d 375void read_info_alternates(const char * relative_base, int depth)
d5a63b99 376{
9577e7e3 377 char *map;
dc49cd76 378 size_t mapsz;
d5a63b99 379 struct stat st;
9cb18f56
JM
380 const char alt_file_name[] = "info/alternates";
381 /* Given that relative_base is no longer than PATH_MAX,
382 ensure that "path" has enough space to append "/", the
383 file name, "info/alternates", and a trailing NUL. */
384 char path[PATH_MAX + 1 + sizeof alt_file_name];
c2f493a4 385 int fd;
d5a63b99 386
9cb18f56 387 sprintf(path, "%s/%s", relative_base, alt_file_name);
f4e51683 388 fd = git_open_noatime(path);
d5a63b99
JH
389 if (fd < 0)
390 return;
391 if (fstat(fd, &st) || (st.st_size == 0)) {
392 close(fd);
9a217f2a 393 return;
ace1534d 394 }
dc49cd76
SP
395 mapsz = xsize_t(st.st_size);
396 map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0);
d5a63b99 397 close(fd);
d5a63b99 398
c5950164 399 link_alt_odb_entries(map, mapsz, '\n', relative_base, depth);
c2f493a4 400
dc49cd76 401 munmap(map, mapsz);
ace1534d
JH
402}
403
bef70b22
DB
404void add_to_alternates_file(const char *reference)
405{
406 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
acd3b9ec 407 int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR);
e6baf4a1 408 char *alt = mkpath("%s\n", reference);
bef70b22
DB
409 write_or_die(fd, alt, strlen(alt));
410 if (commit_lock_file(lock))
411 die("could not close alternates file");
412 if (alt_odb_tail)
c5950164 413 link_alt_odb_entries(alt, strlen(alt), '\n', NULL, 0);
bef70b22
DB
414}
415
fe1b2268 416int foreach_alt_odb(alt_odb_fn fn, void *cb)
d79796bc
JH
417{
418 struct alternate_object_database *ent;
fe1b2268 419 int r = 0;
d79796bc
JH
420
421 prepare_alt_odb();
fe1b2268
JK
422 for (ent = alt_odb_list; ent; ent = ent->next) {
423 r = fn(ent, cb);
424 if (r)
425 break;
426 }
427 return r;
d79796bc
JH
428}
429
c2f493a4
MW
430void prepare_alt_odb(void)
431{
554fe20d 432 const char *alt;
c2f493a4 433
7dc24aa5
SP
434 if (alt_odb_tail)
435 return;
436
c2f493a4
MW
437 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
438 if (!alt) alt = "";
439
c2f493a4 440 alt_odb_tail = &alt_odb_list;
c5950164 441 link_alt_odb_entries(alt, strlen(alt), PATH_SEP, NULL, 0);
c2f493a4
MW
442
443 read_info_alternates(get_object_directory(), 0);
444}
445
33d4221c 446static int freshen_file(const char *fn)
ace1534d 447{
33d4221c
JK
448 struct utimbuf t;
449 t.actime = t.modtime = time(NULL);
450 return !utime(fn, &t);
0f4dc14a 451}
ace1534d 452
33d4221c
JK
453static int check_and_freshen_file(const char *fn, int freshen)
454{
455 if (access(fn, F_OK))
456 return 0;
457 if (freshen && freshen_file(fn))
458 return 0;
459 return 1;
460}
461
462static int check_and_freshen_local(const unsigned char *sha1, int freshen)
463{
464 return check_and_freshen_file(sha1_file_name(sha1), freshen);
465}
466
467static int check_and_freshen_nonlocal(const unsigned char *sha1, int freshen)
0f4dc14a
BC
468{
469 struct alternate_object_database *alt;
9a217f2a 470 prepare_alt_odb();
d5a63b99 471 for (alt = alt_odb_list; alt; alt = alt->next) {
0f4dc14a 472 fill_sha1_path(alt->name, sha1);
33d4221c 473 if (check_and_freshen_file(alt->base, freshen))
c529d75a 474 return 1;
ace1534d 475 }
c529d75a 476 return 0;
ace1534d
JH
477}
478
33d4221c
JK
479static int check_and_freshen(const unsigned char *sha1, int freshen)
480{
481 return check_and_freshen_local(sha1, freshen) ||
482 check_and_freshen_nonlocal(sha1, freshen);
483}
484
485int has_loose_object_nonlocal(const unsigned char *sha1)
486{
487 return check_and_freshen_nonlocal(sha1, 0);
488}
489
0f4dc14a
BC
490static int has_loose_object(const unsigned char *sha1)
491{
33d4221c 492 return check_and_freshen(sha1, 0);
0f4dc14a
BC
493}
494
60bb8b14 495static unsigned int pack_used_ctr;
a53128b6
SP
496static unsigned int pack_mmap_calls;
497static unsigned int peak_pack_open_windows;
498static unsigned int pack_open_windows;
c7934306
SP
499static unsigned int pack_open_fds;
500static unsigned int pack_max_fds;
a53128b6 501static size_t peak_pack_mapped;
60bb8b14 502static size_t pack_mapped;
9a217f2a 503struct packed_git *packed_git;
1f688557 504
b79d18c9 505void pack_report(void)
a53128b6
SP
506{
507 fprintf(stderr,
e05db0fd
PR
508 "pack_report: getpagesize() = %10" SZ_FMT "\n"
509 "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
510 "pack_report: core.packedGitLimit = %10" SZ_FMT "\n",
9e42d6a1
SP
511 sz_fmt(getpagesize()),
512 sz_fmt(packed_git_window_size),
513 sz_fmt(packed_git_limit));
a53128b6
SP
514 fprintf(stderr,
515 "pack_report: pack_used_ctr = %10u\n"
516 "pack_report: pack_mmap_calls = %10u\n"
517 "pack_report: pack_open_windows = %10u / %10u\n"
e05db0fd
PR
518 "pack_report: pack_mapped = "
519 "%10" SZ_FMT " / %10" SZ_FMT "\n",
a53128b6
SP
520 pack_used_ctr,
521 pack_mmap_calls,
522 pack_open_windows, peak_pack_open_windows,
9e42d6a1 523 sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped));
a53128b6
SP
524}
525
d40d535b
MH
526/*
527 * Open and mmap the index file at path, perform a couple of
528 * consistency checks, then record its information to p. Return 0 on
529 * success.
530 */
531static int check_packed_git_idx(const char *path, struct packed_git *p)
1f688557
JH
532{
533 void *idx_map;
42873078 534 struct pack_idx_header *hdr;
dc49cd76 535 size_t idx_size;
74e34e1f 536 uint32_t version, nr, i, *index;
f4e51683 537 int fd = git_open_noatime(path);
1f688557 538 struct stat st;
42873078 539
1f688557
JH
540 if (fd < 0)
541 return -1;
542 if (fstat(fd, &st)) {
543 close(fd);
544 return -1;
545 }
dc49cd76 546 idx_size = xsize_t(st.st_size);
2d88451b
SP
547 if (idx_size < 4 * 256 + 20 + 20) {
548 close(fd);
549 return error("index file %s is too small", path);
550 }
c4712e45 551 idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
1f688557 552 close(fd);
1f688557 553
42873078
NP
554 hdr = idx_map;
555 if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) {
74e34e1f
NP
556 version = ntohl(hdr->idx_version);
557 if (version < 2 || version > 2) {
558 munmap(idx_map, idx_size);
6e1c2344 559 return error("index file %s is version %"PRIu32
74e34e1f
NP
560 " and is not supported by this binary"
561 " (try upgrading GIT to a newer version)",
562 path, version);
563 }
564 } else
565 version = 1;
df1b059d 566
1f688557 567 nr = 0;
42873078 568 index = idx_map;
74e34e1f
NP
569 if (version > 1)
570 index += 2; /* skip index header */
1f688557 571 for (i = 0; i < 256; i++) {
326bf396 572 uint32_t n = ntohl(index[i]);
2d88451b
SP
573 if (n < nr) {
574 munmap(idx_map, idx_size);
df1b059d 575 return error("non-monotonic index %s", path);
2d88451b 576 }
1f688557
JH
577 nr = n;
578 }
579
74e34e1f
NP
580 if (version == 1) {
581 /*
582 * Total size:
583 * - 256 index entries 4 bytes each
584 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
585 * - 20-byte SHA1 of the packfile
586 * - 20-byte SHA1 file checksum
587 */
588 if (idx_size != 4*256 + nr * 24 + 20 + 20) {
589 munmap(idx_map, idx_size);
eef427a0 590 return error("wrong index v1 file size in %s", path);
74e34e1f
NP
591 }
592 } else if (version == 2) {
593 /*
594 * Minimum size:
595 * - 8 bytes of header
596 * - 256 index entries 4 bytes each
597 * - 20-byte sha1 entry * nr
598 * - 4-byte crc entry * nr
599 * - 4-byte offset entry * nr
600 * - 20-byte SHA1 of the packfile
601 * - 20-byte SHA1 file checksum
602 * And after the 4-byte offset table might be a
603 * variable sized table containing 8-byte entries
604 * for offsets larger than 2^31.
605 */
606 unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20;
1164f1e4
LT
607 unsigned long max_size = min_size;
608 if (nr)
609 max_size += (nr - 1)*8;
610 if (idx_size < min_size || idx_size > max_size) {
74e34e1f 611 munmap(idx_map, idx_size);
eef427a0 612 return error("wrong index v2 file size in %s", path);
74e34e1f 613 }
7109c889
JH
614 if (idx_size != min_size &&
615 /*
616 * make sure we can deal with large pack offsets.
617 * 31-bit signed offset won't be enough, neither
618 * 32-bit unsigned one will be.
619 */
620 (sizeof(off_t) <= 4)) {
621 munmap(idx_map, idx_size);
622 return error("pack too large for current definition of off_t in %s", path);
74e34e1f 623 }
2d88451b 624 }
1f688557 625
74e34e1f 626 p->index_version = version;
42873078
NP
627 p->index_data = idx_map;
628 p->index_size = idx_size;
57059091 629 p->num_objects = nr;
1f688557
JH
630 return 0;
631}
632
bc8e478a 633int open_pack_index(struct packed_git *p)
d079837e
SP
634{
635 char *idx_name;
636 int ret;
637
638 if (p->index_data)
639 return 0;
640
641 idx_name = xstrdup(p->pack_name);
642 strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx");
643 ret = check_packed_git_idx(idx_name, p);
644 free(idx_name);
645 return ret;
646}
647
11daf39b
SP
648static void scan_windows(struct packed_git *p,
649 struct packed_git **lru_p,
650 struct pack_window **lru_w,
651 struct pack_window **lru_l)
1f688557 652{
11daf39b
SP
653 struct pack_window *w, *w_l;
654
655 for (w_l = NULL, w = p->windows; w; w = w->next) {
656 if (!w->inuse_cnt) {
657 if (!*lru_w || w->last_used < (*lru_w)->last_used) {
658 *lru_p = p;
659 *lru_w = w;
660 *lru_l = w_l;
54044bf8 661 }
54044bf8 662 }
11daf39b 663 w_l = w;
f9253394 664 }
11daf39b
SP
665}
666
7c3ecb32 667static int unuse_one_window(struct packed_git *current)
11daf39b
SP
668{
669 struct packed_git *p, *lru_p = NULL;
670 struct pack_window *lru_w = NULL, *lru_l = NULL;
671
672 if (current)
673 scan_windows(current, &lru_p, &lru_w, &lru_l);
674 for (p = packed_git; p; p = p->next)
675 scan_windows(p, &lru_p, &lru_w, &lru_l);
54044bf8
SP
676 if (lru_p) {
677 munmap(lru_w->base, lru_w->len);
678 pack_mapped -= lru_w->len;
679 if (lru_l)
680 lru_l->next = lru_w->next;
7c3ecb32 681 else
54044bf8 682 lru_p->windows = lru_w->next;
54044bf8 683 free(lru_w);
a53128b6 684 pack_open_windows--;
54044bf8
SP
685 return 1;
686 }
687 return 0;
f9253394
JH
688}
689
7c3ecb32 690void release_pack_memory(size_t need)
97bfeb34
SP
691{
692 size_t cur = pack_mapped;
7c3ecb32 693 while (need >= (cur - pack_mapped) && unuse_one_window(NULL))
97bfeb34
SP
694 ; /* nothing */
695}
696
02710228
SP
697static void mmap_limit_check(size_t length)
698{
699 static size_t limit = 0;
700 if (!limit) {
701 limit = git_env_ulong("GIT_MMAP_LIMIT", 0);
702 if (!limit)
703 limit = SIZE_MAX;
704 }
705 if (length > limit)
706 die("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX,
707 (uintmax_t)length, (uintmax_t)limit);
708}
709
58ecbd5e
JN
710void *xmmap(void *start, size_t length,
711 int prot, int flags, int fd, off_t offset)
712{
02710228
SP
713 void *ret;
714
715 mmap_limit_check(length);
716 ret = mmap(start, length, prot, flags, fd, offset);
58ecbd5e
JN
717 if (ret == MAP_FAILED) {
718 if (!length)
719 return NULL;
7c3ecb32 720 release_pack_memory(length);
58ecbd5e
JN
721 ret = mmap(start, length, prot, flags, fd, offset);
722 if (ret == MAP_FAILED)
723 die_errno("Out of memory? mmap failed");
724 }
725 return ret;
726}
727
c9ced051
SP
728void close_pack_windows(struct packed_git *p)
729{
730 while (p->windows) {
731 struct pack_window *w = p->windows;
732
733 if (w->inuse_cnt)
734 die("pack '%s' still has open windows to it",
735 p->pack_name);
736 munmap(w->base, w->len);
737 pack_mapped -= w->len;
738 pack_open_windows--;
739 p->windows = w->next;
740 free(w);
741 }
742}
743
88d0db55
BC
744/*
745 * The LRU pack is the one with the oldest MRU window, preferring packs
746 * with no used windows, or the oldest mtime if it has no windows allocated.
747 */
748static void find_lru_pack(struct packed_git *p, struct packed_git **lru_p, struct pack_window **mru_w, int *accept_windows_inuse)
749{
750 struct pack_window *w, *this_mru_w;
751 int has_windows_inuse = 0;
752
753 /*
754 * Reject this pack if it has windows and the previously selected
755 * one does not. If this pack does not have windows, reject
756 * it if the pack file is newer than the previously selected one.
757 */
758 if (*lru_p && !*mru_w && (p->windows || p->mtime > (*lru_p)->mtime))
759 return;
760
761 for (w = this_mru_w = p->windows; w; w = w->next) {
762 /*
763 * Reject this pack if any of its windows are in use,
764 * but the previously selected pack did not have any
765 * inuse windows. Otherwise, record that this pack
766 * has windows in use.
767 */
768 if (w->inuse_cnt) {
769 if (*accept_windows_inuse)
770 has_windows_inuse = 1;
771 else
772 return;
773 }
774
775 if (w->last_used > this_mru_w->last_used)
776 this_mru_w = w;
777
778 /*
779 * Reject this pack if it has windows that have been
780 * used more recently than the previously selected pack.
781 * If the previously selected pack had windows inuse and
782 * we have not encountered a window in this pack that is
783 * inuse, skip this check since we prefer a pack with no
784 * inuse windows to one that has inuse windows.
785 */
786 if (*mru_w && *accept_windows_inuse == has_windows_inuse &&
787 this_mru_w->last_used > (*mru_w)->last_used)
788 return;
789 }
790
791 /*
792 * Select this pack.
793 */
794 *mru_w = this_mru_w;
795 *lru_p = p;
796 *accept_windows_inuse = has_windows_inuse;
797}
798
799static int close_one_pack(void)
800{
801 struct packed_git *p, *lru_p = NULL;
802 struct pack_window *mru_w = NULL;
803 int accept_windows_inuse = 1;
804
805 for (p = packed_git; p; p = p->next) {
806 if (p->pack_fd == -1)
807 continue;
808 find_lru_pack(p, &lru_p, &mru_w, &accept_windows_inuse);
809 }
810
811 if (lru_p) {
812 close(lru_p->pack_fd);
813 pack_open_fds--;
814 lru_p->pack_fd = -1;
815 return 1;
816 }
817
818 return 0;
819}
820
03e79c88 821void unuse_pack(struct pack_window **w_cursor)
f9253394 822{
03e79c88
SP
823 struct pack_window *w = *w_cursor;
824 if (w) {
825 w->inuse_cnt--;
826 *w_cursor = NULL;
827 }
1f688557
JH
828}
829
fa5fc15d
SP
830void close_pack_index(struct packed_git *p)
831{
832 if (p->index_data) {
833 munmap((void *)p->index_data, p->index_size);
834 p->index_data = NULL;
835 }
836}
837
c74faea1
NP
838/*
839 * This is used by git-repack in case a newly created pack happens to
840 * contain the same set of objects as an existing one. In that case
841 * the resulting file might be different even if its name would be the
842 * same. It is best to close any reference to the old pack before it is
01689909 843 * replaced on disk. Of course no index pointers or windows for given pack
c74faea1
NP
844 * must subsist at this point. If ever objects from this pack are requested
845 * again, the new version of the pack will be reinitialized through
846 * reprepare_packed_git().
847 */
848void free_pack_by_name(const char *pack_name)
849{
850 struct packed_git *p, **pp = &packed_git;
851
852 while (*pp) {
853 p = *pp;
854 if (strcmp(pack_name, p->pack_name) == 0) {
fa3a0c94 855 clear_delta_base_cache();
c74faea1 856 close_pack_windows(p);
c7934306 857 if (p->pack_fd != -1) {
c74faea1 858 close(p->pack_fd);
c7934306
SP
859 pack_open_fds--;
860 }
fa5fc15d 861 close_pack_index(p);
c74faea1
NP
862 free(p->bad_object_sha1);
863 *pp = p->next;
c01f51cc
NTND
864 if (last_found_pack == p)
865 last_found_pack = NULL;
c74faea1
NP
866 free(p);
867 return;
868 }
869 pp = &p->next;
870 }
871}
872
a0788266
JS
873static unsigned int get_max_fd_limit(void)
874{
875#ifdef RLIMIT_NOFILE
491a8dec
JH
876 {
877 struct rlimit lim;
a0788266 878
491a8dec
JH
879 if (!getrlimit(RLIMIT_NOFILE, &lim))
880 return lim.rlim_cur;
881 }
882#endif
883
884#ifdef _SC_OPEN_MAX
885 {
886 long open_max = sysconf(_SC_OPEN_MAX);
887 if (0 < open_max)
888 return open_max;
889 /*
890 * Otherwise, we got -1 for one of the two
891 * reasons:
892 *
893 * (1) sysconf() did not understand _SC_OPEN_MAX
894 * and signaled an error with -1; or
895 * (2) sysconf() said there is no limit.
896 *
897 * We _could_ clear errno before calling sysconf() to
898 * tell these two cases apart and return a huge number
899 * in the latter case to let the caller cap it to a
900 * value that is not so selfish, but letting the
901 * fallback OPEN_MAX codepath take care of these cases
902 * is a lot simpler.
903 */
904 }
905#endif
a0788266 906
491a8dec 907#ifdef OPEN_MAX
a0788266
JS
908 return OPEN_MAX;
909#else
910 return 1; /* see the caller ;-) */
911#endif
912}
913
3cf8b462
SP
914/*
915 * Do not call this directly as this leaks p->pack_fd on error return;
916 * call open_packed_git() instead.
917 */
918static int open_packed_git_1(struct packed_git *p)
1f688557 919{
9bc879c1
SP
920 struct stat st;
921 struct pack_header hdr;
922 unsigned char sha1[20];
923 unsigned char *idx_sha1;
2c039da8 924 long fd_flag;
9bc879c1 925
d079837e
SP
926 if (!p->index_data && open_pack_index(p))
927 return error("packfile %s index unavailable", p->pack_name);
928
c7934306 929 if (!pack_max_fds) {
a0788266 930 unsigned int max_fds = get_max_fd_limit();
c7934306
SP
931
932 /* Save 3 for stdin/stdout/stderr, 22 for work */
933 if (25 < max_fds)
934 pack_max_fds = max_fds - 25;
935 else
936 pack_max_fds = 1;
937 }
938
88d0db55 939 while (pack_max_fds <= pack_open_fds && close_one_pack())
c7934306
SP
940 ; /* nothing */
941
f4e51683 942 p->pack_fd = git_open_noatime(p->pack_name);
9bc879c1 943 if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
072db278 944 return -1;
c7934306 945 pack_open_fds++;
9bc879c1
SP
946
947 /* If we created the struct before we had the pack we lack size. */
bf592c50 948 if (!p->pack_size) {
bf592c50 949 if (!S_ISREG(st.st_mode))
072db278 950 return error("packfile %s not a regular file", p->pack_name);
bf592c50 951 p->pack_size = st.st_size;
9bc879c1 952 } else if (p->pack_size != st.st_size)
072db278 953 return error("packfile %s size changed", p->pack_name);
9bc879c1 954
2c039da8
JH
955 /* We leave these file descriptors open with sliding mmap;
956 * there is no point keeping them open across exec(), though.
957 */
958 fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
959 if (fd_flag < 0)
072db278 960 return error("cannot determine file descriptor flags");
2c039da8
JH
961 fd_flag |= FD_CLOEXEC;
962 if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
072db278 963 return error("cannot set FD_CLOEXEC");
2c039da8 964
9bc879c1 965 /* Verify we recognize this pack file format. */
e6e2bd62 966 if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
072db278 967 return error("file %s is far too short to be a packfile", p->pack_name);
9bc879c1 968 if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
072db278 969 return error("file %s is not a GIT packfile", p->pack_name);
9bc879c1 970 if (!pack_version_ok(hdr.hdr_version))
6e1c2344
RJ
971 return error("packfile %s is version %"PRIu32" and not"
972 " supported (try upgrading GIT to a newer version)",
9bc879c1
SP
973 p->pack_name, ntohl(hdr.hdr_version));
974
975 /* Verify the pack matches its index. */
57059091 976 if (p->num_objects != ntohl(hdr.hdr_entries))
6e1c2344
RJ
977 return error("packfile %s claims to have %"PRIu32" objects"
978 " while index indicates %"PRIu32" objects",
57059091
NP
979 p->pack_name, ntohl(hdr.hdr_entries),
980 p->num_objects);
9bc879c1 981 if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
072db278 982 return error("end of packfile %s is unavailable", p->pack_name);
e6e2bd62 983 if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
072db278 984 return error("packfile %s signature is unavailable", p->pack_name);
42873078 985 idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40;
9bc879c1 986 if (hashcmp(sha1, idx_sha1))
072db278
SP
987 return error("packfile %s does not match index", p->pack_name);
988 return 0;
9bc879c1
SP
989}
990
3cf8b462
SP
991static int open_packed_git(struct packed_git *p)
992{
993 if (!open_packed_git_1(p))
994 return 0;
995 if (p->pack_fd != -1) {
996 close(p->pack_fd);
c7934306 997 pack_open_fds--;
3cf8b462
SP
998 p->pack_fd = -1;
999 }
1000 return -1;
1001}
1002
c4001d92 1003static int in_window(struct pack_window *win, off_t offset)
60bb8b14
SP
1004{
1005 /* We must promise at least 20 bytes (one hash) after the
1006 * offset is available from this window, otherwise the offset
1007 * is not actually in this window and a different window (which
1008 * has that one hash excess) must be used. This is to support
1009 * the object header and delta base parsing routines below.
1010 */
1011 off_t win_off = win->offset;
1012 return win_off <= offset
1013 && (offset + 20) <= (win_off + win->len);
1014}
1015
4b25d091 1016unsigned char *use_pack(struct packed_git *p,
03e79c88 1017 struct pack_window **w_cursor,
c4001d92 1018 off_t offset,
ef49a7a0 1019 unsigned long *left)
9bc879c1 1020{
60bb8b14 1021 struct pack_window *win = *w_cursor;
03e79c88 1022
a9d98a14 1023 /* Since packfiles end in a hash of their content and it's
60bb8b14
SP
1024 * pointless to ask for an offset into the middle of that
1025 * hash, and the in_window function above wouldn't match
1026 * don't allow an offset too close to the end of the file.
1027 */
d131b7af
SP
1028 if (!p->pack_size && p->pack_fd == -1 && open_packed_git(p))
1029 die("packfile %s cannot be accessed", p->pack_name);
60bb8b14
SP
1030 if (offset > (p->pack_size - 20))
1031 die("offset beyond end of packfile (truncated pack?)");
1032
1033 if (!win || !in_window(win, offset)) {
1034 if (win)
1035 win->inuse_cnt--;
1036 for (win = p->windows; win; win = win->next) {
1037 if (in_window(win, offset))
1038 break;
1039 }
1040 if (!win) {
78a28df9 1041 size_t window_align = packed_git_window_size / 2;
dc49cd76 1042 off_t len;
d131b7af
SP
1043
1044 if (p->pack_fd == -1 && open_packed_git(p))
1045 die("packfile %s cannot be accessed", p->pack_name);
1046
60bb8b14 1047 win = xcalloc(1, sizeof(*win));
78a28df9 1048 win->offset = (offset / window_align) * window_align;
dc49cd76
SP
1049 len = p->pack_size - win->offset;
1050 if (len > packed_git_window_size)
1051 len = packed_git_window_size;
1052 win->len = (size_t)len;
60bb8b14 1053 pack_mapped += win->len;
11daf39b 1054 while (packed_git_limit < pack_mapped
7c3ecb32 1055 && unuse_one_window(p))
60bb8b14 1056 ; /* nothing */
c4712e45 1057 win->base = xmmap(NULL, win->len,
60bb8b14
SP
1058 PROT_READ, MAP_PRIVATE,
1059 p->pack_fd, win->offset);
1060 if (win->base == MAP_FAILED)
73b4e4be
SP
1061 die("packfile %s cannot be mapped: %s",
1062 p->pack_name,
1063 strerror(errno));
d131b7af
SP
1064 if (!win->offset && win->len == p->pack_size
1065 && !p->do_not_close) {
1066 close(p->pack_fd);
1067 pack_open_fds--;
1068 p->pack_fd = -1;
1069 }
a53128b6
SP
1070 pack_mmap_calls++;
1071 pack_open_windows++;
1072 if (pack_mapped > peak_pack_mapped)
1073 peak_pack_mapped = pack_mapped;
1074 if (pack_open_windows > peak_pack_open_windows)
1075 peak_pack_open_windows = pack_open_windows;
60bb8b14
SP
1076 win->next = p->windows;
1077 p->windows = win;
1078 }
1f688557 1079 }
03e79c88
SP
1080 if (win != *w_cursor) {
1081 win->last_used = pack_used_ctr++;
1082 win->inuse_cnt++;
1083 *w_cursor = win;
1084 }
60bb8b14 1085 offset -= win->offset;
03e79c88 1086 if (left)
dc49cd76 1087 *left = win->len - xsize_t(offset);
03e79c88 1088 return win->base + offset;
1f688557
JH
1089}
1090
27d69a46
NP
1091static struct packed_git *alloc_packed_git(int extra)
1092{
1093 struct packed_git *p = xmalloc(sizeof(*p) + extra);
1094 memset(p, 0, sizeof(*p));
1095 p->pack_fd = -1;
1096 return p;
1097}
1098
e0500293
JN
1099static void try_to_free_pack_memory(size_t size)
1100{
7c3ecb32 1101 release_pack_memory(size);
e0500293
JN
1102}
1103
42873078 1104struct packed_git *add_packed_git(const char *path, int path_len, int local)
1f688557 1105{
e0500293 1106 static int have_set_try_to_free_routine;
1f688557 1107 struct stat st;
27d69a46 1108 struct packed_git *p = alloc_packed_git(path_len + 2);
1f688557 1109
e0500293
JN
1110 if (!have_set_try_to_free_routine) {
1111 have_set_try_to_free_routine = 1;
1112 set_try_to_free_routine(try_to_free_pack_memory);
1113 }
1114
42873078
NP
1115 /*
1116 * Make sure a corresponding .pack file exists and that
1117 * the index looks sane.
1118 */
1119 path_len -= strlen(".idx");
27d69a46
NP
1120 if (path_len < 1) {
1121 free(p);
1f688557 1122 return NULL;
27d69a46 1123 }
42873078 1124 memcpy(p->pack_name, path, path_len);
8d25931d
BC
1125
1126 strcpy(p->pack_name + path_len, ".keep");
1127 if (!access(p->pack_name, F_OK))
1128 p->pack_keep = 1;
1129
42873078 1130 strcpy(p->pack_name + path_len, ".pack");
d079837e 1131 if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
42873078 1132 free(p);
1f688557
JH
1133 return NULL;
1134 }
42873078 1135
1f688557
JH
1136 /* ok, it looks sane as far as we can check without
1137 * actually mapping the pack file.
1138 */
1f688557 1139 p->pack_size = st.st_size;
9d835df2 1140 p->pack_local = local;
b867092f 1141 p->mtime = st.st_mtime;
42873078
NP
1142 if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1))
1143 hashclr(p->sha1);
1f688557
JH
1144 return p;
1145}
1146
7b64469a 1147struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path)
c508df5e 1148{
42873078 1149 const char *path = sha1_pack_name(sha1);
27d69a46 1150 struct packed_git *p = alloc_packed_git(strlen(path) + 1);
bf592c50 1151
27d69a46
NP
1152 strcpy(p->pack_name, path);
1153 hashcpy(p->sha1, sha1);
42873078
NP
1154 if (check_packed_git_idx(idx_path, p)) {
1155 free(p);
bf592c50 1156 return NULL;
42873078 1157 }
bf592c50 1158
bf592c50
DB
1159 return p;
1160}
1161
1162void install_packed_git(struct packed_git *pack)
1163{
c7934306
SP
1164 if (pack->pack_fd != -1)
1165 pack_open_fds++;
1166
bf592c50
DB
1167 pack->next = packed_git;
1168 packed_git = pack;
1169}
1170
543c5caa
NTND
1171void (*report_garbage)(const char *desc, const char *path);
1172
1173static void report_helper(const struct string_list *list,
1174 int seen_bits, int first, int last)
1175{
1176 const char *msg;
1177 switch (seen_bits) {
1178 case 0:
235e8d59 1179 msg = "no corresponding .idx or .pack";
543c5caa
NTND
1180 break;
1181 case 1:
1182 msg = "no corresponding .idx";
1183 break;
1184 case 2:
1185 msg = "no corresponding .pack";
1186 break;
1187 default:
1188 return;
1189 }
1190 for (; first < last; first++)
1191 report_garbage(msg, list->items[first].string);
1192}
1193
1194static void report_pack_garbage(struct string_list *list)
1195{
1196 int i, baselen = -1, first = 0, seen_bits = 0;
1197
1198 if (!report_garbage)
1199 return;
1200
1201 sort_string_list(list);
1202
1203 for (i = 0; i < list->nr; i++) {
1204 const char *path = list->items[i].string;
1205 if (baselen != -1 &&
1206 strncmp(path, list->items[first].string, baselen)) {
1207 report_helper(list, seen_bits, first, i);
1208 baselen = -1;
1209 seen_bits = 0;
1210 }
1211 if (baselen == -1) {
1212 const char *dot = strrchr(path, '.');
1213 if (!dot) {
1214 report_garbage("garbage found", path);
1215 continue;
1216 }
1217 baselen = dot - path + 1;
1218 first = i;
1219 }
1220 if (!strcmp(path + baselen, "pack"))
1221 seen_bits |= 1;
1222 else if (!strcmp(path + baselen, "idx"))
1223 seen_bits |= 2;
1224 }
1225 report_helper(list, seen_bits, first, list->nr);
1226}
1227
9d835df2 1228static void prepare_packed_git_one(char *objdir, int local)
1f688557 1229{
880fb8de
RS
1230 struct strbuf path = STRBUF_INIT;
1231 size_t dirnamelen;
1f688557
JH
1232 DIR *dir;
1233 struct dirent *de;
543c5caa 1234 struct string_list garbage = STRING_LIST_INIT_DUP;
1f688557 1235
880fb8de
RS
1236 strbuf_addstr(&path, objdir);
1237 strbuf_addstr(&path, "/pack");
1238 dir = opendir(path.buf);
b5b16990 1239 if (!dir) {
26125f6b 1240 if (errno != ENOENT)
bd2afde8 1241 error("unable to open object pack directory: %s: %s",
880fb8de
RS
1242 path.buf, strerror(errno));
1243 strbuf_release(&path);
1f688557 1244 return;
b5b16990 1245 }
880fb8de
RS
1246 strbuf_addch(&path, '/');
1247 dirnamelen = path.len;
1f688557 1248 while ((de = readdir(dir)) != NULL) {
1f688557 1249 struct packed_git *p;
47bf4b0f 1250 size_t base_len;
543c5caa
NTND
1251
1252 if (is_dot_or_dotdot(de->d_name))
9cb18f56
JM
1253 continue;
1254
880fb8de
RS
1255 strbuf_setlen(&path, dirnamelen);
1256 strbuf_addstr(&path, de->d_name);
d90906a9 1257
47bf4b0f
JK
1258 base_len = path.len;
1259 if (strip_suffix_mem(path.buf, &base_len, ".idx")) {
d90906a9
NTND
1260 /* Don't reopen a pack we already have. */
1261 for (p = packed_git; p; p = p->next) {
47bf4b0f
JK
1262 size_t len;
1263 if (strip_suffix(p->pack_name, ".pack", &len) &&
1264 len == base_len &&
1265 !memcmp(p->pack_name, path.buf, len))
d90906a9
NTND
1266 break;
1267 }
1268 if (p == NULL &&
1269 /*
1270 * See if it really is a valid .idx file with
1271 * corresponding .pack file that we can map.
1272 */
880fb8de 1273 (p = add_packed_git(path.buf, path.len, local)) != NULL)
d90906a9 1274 install_packed_git(p);
86f7780c 1275 }
543c5caa
NTND
1276
1277 if (!report_garbage)
1278 continue;
1279
2975c770
JK
1280 if (ends_with(de->d_name, ".idx") ||
1281 ends_with(de->d_name, ".pack") ||
1282 ends_with(de->d_name, ".bitmap") ||
1283 ends_with(de->d_name, ".keep"))
880fb8de 1284 string_list_append(&garbage, path.buf);
543c5caa 1285 else
880fb8de 1286 report_garbage("garbage found", path.buf);
1f688557 1287 }
5b35bcd5 1288 closedir(dir);
543c5caa
NTND
1289 report_pack_garbage(&garbage);
1290 string_list_clear(&garbage, 0);
880fb8de 1291 strbuf_release(&path);
1f688557
JH
1292}
1293
b867092f
JH
1294static int sort_pack(const void *a_, const void *b_)
1295{
1296 struct packed_git *a = *((struct packed_git **)a_);
1297 struct packed_git *b = *((struct packed_git **)b_);
1298 int st;
1299
1300 /*
1301 * Local packs tend to contain objects specific to our
1302 * variant of the project than remote ones. In addition,
1303 * remote ones could be on a network mounted filesystem.
1304 * Favor local ones for these reasons.
1305 */
1306 st = a->pack_local - b->pack_local;
1307 if (st)
1308 return -st;
1309
1310 /*
1311 * Younger packs tend to contain more recent objects,
1312 * and more recent objects tend to get accessed more
1313 * often.
1314 */
1315 if (a->mtime < b->mtime)
1316 return 1;
1317 else if (a->mtime == b->mtime)
1318 return 0;
1319 return -1;
1320}
1321
1322static void rearrange_packed_git(void)
1323{
1324 struct packed_git **ary, *p;
1325 int i, n;
1326
1327 for (n = 0, p = packed_git; p; p = p->next)
1328 n++;
1329 if (n < 2)
1330 return;
1331
1332 /* prepare an array of packed_git for easier sorting */
1333 ary = xcalloc(n, sizeof(struct packed_git *));
1334 for (n = 0, p = packed_git; p; p = p->next)
1335 ary[n++] = p;
1336
1337 qsort(ary, n, sizeof(struct packed_git *), sort_pack);
1338
1339 /* link them back again */
1340 for (i = 0; i < n - 1; i++)
1341 ary[i]->next = ary[i + 1];
1342 ary[n - 1]->next = NULL;
1343 packed_git = ary[0];
1344
1345 free(ary);
1346}
1347
637cdd9d 1348static int prepare_packed_git_run_once = 0;
9a217f2a 1349void prepare_packed_git(void)
1f688557 1350{
d5a63b99 1351 struct alternate_object_database *alt;
1f688557 1352
637cdd9d 1353 if (prepare_packed_git_run_once)
1f688557 1354 return;
9d835df2 1355 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 1356 prepare_alt_odb();
d5a63b99 1357 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 1358 alt->name[-1] = 0;
9d835df2 1359 prepare_packed_git_one(alt->base, 0);
1494e038 1360 alt->name[-1] = '/';
1f688557 1361 }
b867092f 1362 rearrange_packed_git();
637cdd9d
JK
1363 prepare_packed_git_run_once = 1;
1364}
1365
fc04c412 1366void reprepare_packed_git(void)
637cdd9d
JK
1367{
1368 prepare_packed_git_run_once = 0;
1369 prepare_packed_git();
1f688557
JH
1370}
1371
8eca0b47
NP
1372static void mark_bad_packed_object(struct packed_git *p,
1373 const unsigned char *sha1)
1374{
1375 unsigned i;
1376 for (i = 0; i < p->num_bad_objects; i++)
1377 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1378 return;
1379 p->bad_object_sha1 = xrealloc(p->bad_object_sha1, 20 * (p->num_bad_objects + 1));
1380 hashcpy(p->bad_object_sha1 + 20 * p->num_bad_objects, sha1);
1381 p->num_bad_objects++;
1382}
1383
b6c4cecc 1384static const struct packed_git *has_packed_and_bad(const unsigned char *sha1)
ac939109
NP
1385{
1386 struct packed_git *p;
1387 unsigned i;
1388
1389 for (p = packed_git; p; p = p->next)
1390 for (i = 0; i < p->num_bad_objects; i++)
1391 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
b6c4cecc
JH
1392 return p;
1393 return NULL;
ac939109
NP
1394}
1395
090ea126
NTND
1396/*
1397 * With an in-core object data in "map", rehash it to make sure the
1398 * object name actually matches "sha1" to detect object corruption.
1399 * With "map" == NULL, try reading the object named with "sha1" using
1400 * the streaming interface and rehash it to do the same.
1401 */
1402int check_sha1_signature(const unsigned char *sha1, void *map,
1403 unsigned long size, const char *type)
0fcfd160
LT
1404{
1405 unsigned char real_sha1[20];
090ea126
NTND
1406 enum object_type obj_type;
1407 struct git_istream *st;
1408 git_SHA_CTX c;
1409 char hdr[32];
1410 int hdrlen;
1411
1412 if (map) {
1413 hash_sha1_file(map, size, type, real_sha1);
1414 return hashcmp(sha1, real_sha1) ? -1 : 0;
1415 }
1416
1417 st = open_istream(sha1, &obj_type, &size, NULL);
1418 if (!st)
1419 return -1;
1420
1421 /* Generate the header */
1422 hdrlen = sprintf(hdr, "%s %lu", typename(obj_type), size) + 1;
1423
1424 /* Sha1.. */
1425 git_SHA1_Init(&c);
1426 git_SHA1_Update(&c, hdr, hdrlen);
1427 for (;;) {
1428 char buf[1024 * 16];
1429 ssize_t readlen = read_istream(st, buf, sizeof(buf));
1430
f54fac53
JK
1431 if (readlen < 0) {
1432 close_istream(st);
1433 return -1;
1434 }
090ea126
NTND
1435 if (!readlen)
1436 break;
1437 git_SHA1_Update(&c, buf, readlen);
1438 }
1439 git_SHA1_Final(real_sha1, &c);
1440 close_istream(st);
a89fccd2 1441 return hashcmp(sha1, real_sha1) ? -1 : 0;
0fcfd160
LT
1442}
1443
ec73f580 1444int git_open_noatime(const char *name)
44d1c19e
LT
1445{
1446 static int sha1_file_open_flag = O_NOATIME;
44d1c19e 1447
f2e872aa
SP
1448 for (;;) {
1449 int fd = open(name, O_RDONLY | sha1_file_open_flag);
44d1c19e 1450 if (fd >= 0)
f2e872aa
SP
1451 return fd;
1452
f2e872aa
SP
1453 /* Might the failure be due to O_NOATIME? */
1454 if (errno != ENOENT && sha1_file_open_flag) {
44d1c19e 1455 sha1_file_open_flag = 0;
f2e872aa
SP
1456 continue;
1457 }
1458
1459 return -1;
44d1c19e 1460 }
44d1c19e
LT
1461}
1462
052fe5ea
JK
1463static int stat_sha1_file(const unsigned char *sha1, struct stat *st)
1464{
052fe5ea
JK
1465 struct alternate_object_database *alt;
1466
30d6c6ea 1467 if (!lstat(sha1_file_name(sha1), st))
052fe5ea
JK
1468 return 0;
1469
1470 prepare_alt_odb();
1471 errno = ENOENT;
1472 for (alt = alt_odb_list; alt; alt = alt->next) {
30d6c6ea 1473 fill_sha1_path(alt->name, sha1);
052fe5ea
JK
1474 if (!lstat(alt->base, st))
1475 return 0;
1476 }
1477
1478 return -1;
1479}
1480
44d1c19e
LT
1481static int open_sha1_file(const unsigned char *sha1)
1482{
1483 int fd;
44d1c19e 1484 struct alternate_object_database *alt;
d6c8a05b 1485 int most_interesting_errno;
44d1c19e 1486
30d6c6ea 1487 fd = git_open_noatime(sha1_file_name(sha1));
44d1c19e
LT
1488 if (fd >= 0)
1489 return fd;
d6c8a05b 1490 most_interesting_errno = errno;
44d1c19e
LT
1491
1492 prepare_alt_odb();
44d1c19e 1493 for (alt = alt_odb_list; alt; alt = alt->next) {
30d6c6ea 1494 fill_sha1_path(alt->name, sha1);
f4e51683 1495 fd = git_open_noatime(alt->base);
44d1c19e
LT
1496 if (fd >= 0)
1497 return fd;
d6c8a05b
JK
1498 if (most_interesting_errno == ENOENT)
1499 most_interesting_errno = errno;
44d1c19e 1500 }
d6c8a05b 1501 errno = most_interesting_errno;
44d1c19e
LT
1502 return -1;
1503}
1504
f0270efd 1505void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
0fcfd160 1506{
0fcfd160 1507 void *map;
144bde78 1508 int fd;
ace1534d 1509
44d1c19e
LT
1510 fd = open_sha1_file(sha1);
1511 map = NULL;
1512 if (fd >= 0) {
1513 struct stat st;
0fcfd160 1514
44d1c19e
LT
1515 if (!fstat(fd, &st)) {
1516 *size = xsize_t(st.st_size);
33e42de0
MM
1517 if (!*size) {
1518 /* mmap() is forbidden on empty files */
1519 error("object file %s is empty", sha1_file_name(sha1));
1520 return NULL;
1521 }
44d1c19e 1522 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
144bde78 1523 }
44d1c19e 1524 close(fd);
0fcfd160 1525 }
0fcfd160
LT
1526 return map;
1527}
1528
09ded04b
NP
1529unsigned long unpack_object_header_buffer(const unsigned char *buf,
1530 unsigned long len, enum object_type *type, unsigned long *sizep)
c4483576 1531{
ad1ed5ee 1532 unsigned shift;
48fb7deb 1533 unsigned long size, c;
ad1ed5ee
JH
1534 unsigned long used = 0;
1535
1536 c = buf[used++];
1537 *type = (c >> 4) & 7;
1538 size = c & 15;
1539 shift = 4;
1540 while (c & 0x80) {
f630cfda 1541 if (len <= used || bitsizeof(long) <= shift) {
09ded04b 1542 error("bad object header");
ea4f9685
JH
1543 size = used = 0;
1544 break;
09ded04b 1545 }
ad1ed5ee
JH
1546 c = buf[used++];
1547 size += (c & 0x7f) << shift;
1548 shift += 7;
1549 }
1550 *sizep = size;
1551 return used;
1552}
1553
eb4f4076 1554int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
ad1ed5ee 1555{
c4483576
LT
1556 /* Get the data stream */
1557 memset(stream, 0, sizeof(*stream));
1558 stream->next_in = map;
1559 stream->avail_in = mapsize;
1560 stream->next_out = buffer;
93821bd9
LT
1561 stream->avail_out = bufsiz;
1562
39c68542 1563 git_inflate_init(stream);
cc5c54e7 1564 return git_inflate(stream, 0);
c4483576
LT
1565}
1566
ef49a7a0 1567static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
5180cacc
LT
1568{
1569 int bytes = strlen(buffer) + 1;
3aee68aa 1570 unsigned char *buf = xmallocz(size);
93821bd9 1571 unsigned long n;
7efbff75 1572 int status = Z_OK;
5180cacc 1573
93821bd9
LT
1574 n = stream->total_out - bytes;
1575 if (n > size)
1576 n = size;
1577 memcpy(buf, (char *) buffer + bytes, n);
1578 bytes = n;
456cdf6e
LT
1579 if (bytes <= size) {
1580 /*
1581 * The above condition must be (bytes <= size), not
1582 * (bytes < size). In other words, even though we
ccf5ace0 1583 * expect no more output and set avail_out to zero,
456cdf6e
LT
1584 * the input zlib stream may have bytes that express
1585 * "this concludes the stream", and we *do* want to
1586 * eat that input.
1587 *
1588 * Otherwise we would not be able to test that we
1589 * consumed all the input to reach the expected size;
1590 * we also want to check that zlib tells us that all
1591 * went well with status == Z_STREAM_END at the end.
1592 */
5180cacc
LT
1593 stream->next_out = buf + bytes;
1594 stream->avail_out = size - bytes;
7efbff75 1595 while (status == Z_OK)
39c68542 1596 status = git_inflate(stream, Z_FINISH);
5180cacc 1597 }
456cdf6e 1598 if (status == Z_STREAM_END && !stream->avail_in) {
39c68542 1599 git_inflate_end(stream);
7efbff75
JH
1600 return buf;
1601 }
1602
1603 if (status < 0)
1604 error("corrupt loose object '%s'", sha1_to_hex(sha1));
1605 else if (stream->avail_in)
1606 error("garbage at end of loose object '%s'",
1607 sha1_to_hex(sha1));
1608 free(buf);
1609 return NULL;
5180cacc
LT
1610}
1611
1612/*
1613 * We used to just use "sscanf()", but that's actually way
1614 * too permissive for what we want to check. So do an anal
1615 * object header parse by hand.
1616 */
f0270efd 1617int parse_sha1_header(const char *hdr, unsigned long *sizep)
5180cacc 1618{
21666f1a 1619 char type[10];
5180cacc
LT
1620 int i;
1621 unsigned long size;
1622
1623 /*
a6080a0a 1624 * The type can be at most ten bytes (including the
5180cacc 1625 * terminating '\0' that we add), and is followed by
21666f1a 1626 * a space.
5180cacc 1627 */
21666f1a 1628 i = 0;
5180cacc
LT
1629 for (;;) {
1630 char c = *hdr++;
1631 if (c == ' ')
1632 break;
21666f1a
NP
1633 type[i++] = c;
1634 if (i >= sizeof(type))
5180cacc 1635 return -1;
5180cacc 1636 }
21666f1a 1637 type[i] = 0;
5180cacc
LT
1638
1639 /*
1640 * The length must follow immediately, and be in canonical
1641 * decimal format (ie "010" is not valid).
1642 */
1643 size = *hdr++ - '0';
1644 if (size > 9)
1645 return -1;
1646 if (size) {
1647 for (;;) {
1648 unsigned long c = *hdr - '0';
1649 if (c > 9)
1650 break;
1651 hdr++;
1652 size = size * 10 + c;
1653 }
1654 }
1655 *sizep = size;
1656
1657 /*
1658 * The length must be followed by a zero byte
1659 */
21666f1a 1660 return *hdr ? -1 : type_from_string(type);
5180cacc
LT
1661}
1662
7efbff75 1663static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
0fcfd160 1664{
5180cacc 1665 int ret;
ef49a7a0 1666 git_zstream stream;
5180cacc 1667 char hdr[8192];
0fcfd160 1668
5180cacc 1669 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
21666f1a 1670 if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
0fcfd160
LT
1671 return NULL;
1672
7efbff75 1673 return unpack_sha1_rest(&stream, hdr, *size, sha1);
0fcfd160
LT
1674}
1675
54dab52a
NP
1676unsigned long get_size_from_delta(struct packed_git *p,
1677 struct pack_window **w_curs,
1678 off_t curpos)
1679{
1680 const unsigned char *data;
1681 unsigned char delta_head[20], *in;
ef49a7a0 1682 git_zstream stream;
54dab52a
NP
1683 int st;
1684
1685 memset(&stream, 0, sizeof(stream));
1686 stream.next_out = delta_head;
1687 stream.avail_out = sizeof(delta_head);
1688
39c68542 1689 git_inflate_init(&stream);
54dab52a
NP
1690 do {
1691 in = use_pack(p, w_curs, curpos, &stream.avail_in);
1692 stream.next_in = in;
39c68542 1693 st = git_inflate(&stream, Z_FINISH);
54dab52a
NP
1694 curpos += stream.next_in - in;
1695 } while ((st == Z_OK || st == Z_BUF_ERROR) &&
1696 stream.total_out < sizeof(delta_head));
39c68542 1697 git_inflate_end(&stream);
3d77d877
NP
1698 if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) {
1699 error("delta data unpack-initial failed");
1700 return 0;
1701 }
54dab52a
NP
1702
1703 /* Examine the initial part of the delta to figure out
1704 * the result size.
1705 */
1706 data = delta_head;
1707
1708 /* ignore base size */
1709 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1710
1711 /* Read the result size */
1712 return get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1713}
1714
c4001d92 1715static off_t get_delta_base(struct packed_git *p,
03e79c88 1716 struct pack_window **w_curs,
c4001d92 1717 off_t *curpos,
21666f1a 1718 enum object_type type,
c4001d92 1719 off_t delta_obj_offset)
eb32d236 1720{
2b87c45b 1721 unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
c4001d92 1722 off_t base_offset;
eb32d236 1723
8d8a4ea5
SP
1724 /* use_pack() assured us we have [base_info, base_info + 20)
1725 * as a range that we can look at without walking off the
1726 * end of the mapped window. Its actually the hash size
1727 * that is assured. An OFS_DELTA longer than the hash size
1728 * is stupid, as then a REF_DELTA would be smaller to store.
1729 */
21666f1a 1730 if (type == OBJ_OFS_DELTA) {
eb32d236
NP
1731 unsigned used = 0;
1732 unsigned char c = base_info[used++];
1733 base_offset = c & 127;
1734 while (c & 128) {
1735 base_offset += 1;
8723f216 1736 if (!base_offset || MSB(base_offset, 7))
8eca0b47 1737 return 0; /* overflow */
eb32d236
NP
1738 c = base_info[used++];
1739 base_offset = (base_offset << 7) + (c & 127);
1740 }
1741 base_offset = delta_obj_offset - base_offset;
d8f32556 1742 if (base_offset <= 0 || base_offset >= delta_obj_offset)
8eca0b47 1743 return 0; /* out of bound */
2b87c45b 1744 *curpos += used;
21666f1a 1745 } else if (type == OBJ_REF_DELTA) {
eb32d236
NP
1746 /* The base entry _must_ be in the same pack */
1747 base_offset = find_pack_entry_one(base_info, p);
2b87c45b 1748 *curpos += 20;
eb32d236
NP
1749 } else
1750 die("I am totally screwed");
2b87c45b 1751 return base_offset;
eb32d236
NP
1752}
1753
5d642e75
JK
1754/*
1755 * Like get_delta_base above, but we return the sha1 instead of the pack
1756 * offset. This means it is cheaper for REF deltas (we do not have to do
1757 * the final object lookup), but more expensive for OFS deltas (we
1758 * have to load the revidx to convert the offset back into a sha1).
1759 */
1760static const unsigned char *get_delta_base_sha1(struct packed_git *p,
1761 struct pack_window **w_curs,
1762 off_t curpos,
1763 enum object_type type,
1764 off_t delta_obj_offset)
1765{
1766 if (type == OBJ_REF_DELTA) {
1767 unsigned char *base = use_pack(p, w_curs, curpos, NULL);
1768 return base;
1769 } else if (type == OBJ_OFS_DELTA) {
1770 struct revindex_entry *revidx;
1771 off_t base_offset = get_delta_base(p, w_curs, &curpos,
1772 type, delta_obj_offset);
1773
1774 if (!base_offset)
1775 return NULL;
1776
1777 revidx = find_pack_revindex(p, base_offset);
1778 if (!revidx)
1779 return NULL;
1780
1781 return nth_packed_object_sha1(p, revidx->nr);
1782 } else
1783 return NULL;
1784}
1785
f8c8abc5
JH
1786int unpack_object_header(struct packed_git *p,
1787 struct pack_window **w_curs,
1788 off_t *curpos,
1789 unsigned long *sizep)
a733cb60 1790{
03e79c88 1791 unsigned char *base;
ef49a7a0 1792 unsigned long left;
ad1ed5ee 1793 unsigned long used;
2b87c45b 1794 enum object_type type;
a733cb60 1795
8d8a4ea5 1796 /* use_pack() assures us we have [base, base + 20) available
0353a0c4 1797 * as a range that we can look at. (Its actually the hash
3dff5379 1798 * size that is assured.) With our object header encoding
8d8a4ea5
SP
1799 * the maximum deflated object size is 2^137, which is just
1800 * insane, so we know won't exceed what we have been given.
1801 */
2b87c45b 1802 base = use_pack(p, w_curs, *curpos, &left);
09ded04b
NP
1803 used = unpack_object_header_buffer(base, left, &type, sizep);
1804 if (!used) {
1805 type = OBJ_BAD;
1806 } else
1807 *curpos += used;
ad1ed5ee 1808
2b87c45b 1809 return type;
a733cb60
LT
1810}
1811
790d96c0
TR
1812static int retry_bad_packed_offset(struct packed_git *p, off_t obj_offset)
1813{
1814 int type;
1815 struct revindex_entry *revidx;
1816 const unsigned char *sha1;
1817 revidx = find_pack_revindex(p, obj_offset);
1818 if (!revidx)
1819 return OBJ_BAD;
1820 sha1 = nth_packed_object_sha1(p, revidx->nr);
1821 mark_bad_packed_object(p, sha1);
1822 type = sha1_object_info(sha1, NULL);
1823 if (type <= OBJ_NONE)
1824 return OBJ_BAD;
1825 return type;
1826}
1827
790d96c0
TR
1828#define POI_STACK_PREALLOC 64
1829
90191d37
JK
1830static enum object_type packed_to_object_type(struct packed_git *p,
1831 off_t obj_offset,
1832 enum object_type type,
1833 struct pack_window **w_curs,
1834 off_t curpos)
1f688557 1835{
790d96c0
TR
1836 off_t small_poi_stack[POI_STACK_PREALLOC];
1837 off_t *poi_stack = small_poi_stack;
1838 int poi_stack_nr = 0, poi_stack_alloc = POI_STACK_PREALLOC;
5db47c2b 1839
790d96c0
TR
1840 while (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
1841 off_t base_offset;
90191d37 1842 unsigned long size;
790d96c0
TR
1843 /* Push the object we're going to leave behind */
1844 if (poi_stack_nr >= poi_stack_alloc && poi_stack == small_poi_stack) {
1845 poi_stack_alloc = alloc_nr(poi_stack_nr);
1846 poi_stack = xmalloc(sizeof(off_t)*poi_stack_alloc);
1847 memcpy(poi_stack, small_poi_stack, sizeof(off_t)*poi_stack_nr);
1848 } else {
1849 ALLOC_GROW(poi_stack, poi_stack_nr+1, poi_stack_alloc);
1850 }
1851 poi_stack[poi_stack_nr++] = obj_offset;
1852 /* If parsing the base offset fails, just unwind */
90191d37 1853 base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
790d96c0
TR
1854 if (!base_offset)
1855 goto unwind;
1856 curpos = obj_offset = base_offset;
90191d37 1857 type = unpack_object_header(p, w_curs, &curpos, &size);
790d96c0
TR
1858 if (type <= OBJ_NONE) {
1859 /* If getting the base itself fails, we first
1860 * retry the base, otherwise unwind */
1861 type = retry_bad_packed_offset(p, base_offset);
1862 if (type > OBJ_NONE)
1863 goto out;
1864 goto unwind;
1865 }
1866 }
1867
21666f1a 1868 switch (type) {
790d96c0 1869 case OBJ_BAD:
a733cb60 1870 case OBJ_COMMIT:
a733cb60 1871 case OBJ_TREE:
a733cb60 1872 case OBJ_BLOB:
a733cb60 1873 case OBJ_TAG:
a69d0943 1874 break;
1f688557 1875 default:
3d77d877
NP
1876 error("unknown object type %i at offset %"PRIuMAX" in %s",
1877 type, (uintmax_t)obj_offset, p->pack_name);
1878 type = OBJ_BAD;
1f688557 1879 }
790d96c0
TR
1880
1881out:
1882 if (poi_stack != small_poi_stack)
1883 free(poi_stack);
21666f1a 1884 return type;
790d96c0
TR
1885
1886unwind:
1887 while (poi_stack_nr) {
1888 obj_offset = poi_stack[--poi_stack_nr];
1889 type = retry_bad_packed_offset(p, obj_offset);
1890 if (type > OBJ_NONE)
1891 goto out;
1892 }
1893 type = OBJ_BAD;
1894 goto out;
1f688557
JH
1895}
1896
90191d37 1897static int packed_object_info(struct packed_git *p, off_t obj_offset,
23c339c0 1898 struct object_info *oi)
90191d37
JK
1899{
1900 struct pack_window *w_curs = NULL;
1901 unsigned long size;
1902 off_t curpos = obj_offset;
1903 enum object_type type;
1904
412916ee
JK
1905 /*
1906 * We always get the representation type, but only convert it to
1907 * a "real" type later if the caller is interested.
1908 */
90191d37
JK
1909 type = unpack_object_header(p, &w_curs, &curpos, &size);
1910
23c339c0 1911 if (oi->sizep) {
90191d37
JK
1912 if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
1913 off_t tmp_pos = curpos;
1914 off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos,
1915 type, obj_offset);
1916 if (!base_offset) {
1917 type = OBJ_BAD;
1918 goto out;
1919 }
23c339c0
JK
1920 *oi->sizep = get_size_from_delta(p, &w_curs, tmp_pos);
1921 if (*oi->sizep == 0) {
90191d37
JK
1922 type = OBJ_BAD;
1923 goto out;
1924 }
1925 } else {
23c339c0 1926 *oi->sizep = size;
90191d37
JK
1927 }
1928 }
1929
23c339c0 1930 if (oi->disk_sizep) {
90191d37 1931 struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
23c339c0 1932 *oi->disk_sizep = revidx[1].offset - obj_offset;
90191d37
JK
1933 }
1934
23c339c0
JK
1935 if (oi->typep) {
1936 *oi->typep = packed_to_object_type(p, obj_offset, type, &w_curs, curpos);
1937 if (*oi->typep < 0) {
412916ee
JK
1938 type = OBJ_BAD;
1939 goto out;
1940 }
1941 }
90191d37 1942
5d642e75
JK
1943 if (oi->delta_base_sha1) {
1944 if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
1945 const unsigned char *base;
1946
1947 base = get_delta_base_sha1(p, &w_curs, curpos,
1948 type, obj_offset);
1949 if (!base) {
1950 type = OBJ_BAD;
1951 goto out;
1952 }
1953
1954 hashcpy(oi->delta_base_sha1, base);
1955 } else
1956 hashclr(oi->delta_base_sha1);
1957 }
1958
90191d37
JK
1959out:
1960 unuse_pack(&w_curs);
1961 return type;
1962}
1963
eb950c19 1964static void *unpack_compressed_entry(struct packed_git *p,
03e79c88 1965 struct pack_window **w_curs,
c4001d92 1966 off_t curpos,
eb950c19 1967 unsigned long size)
de530aaa
SP
1968{
1969 int st;
ef49a7a0 1970 git_zstream stream;
079afb18 1971 unsigned char *buffer, *in;
de530aaa 1972
735efde8
NTND
1973 buffer = xmallocz_gently(size);
1974 if (!buffer)
1975 return NULL;
de530aaa 1976 memset(&stream, 0, sizeof(stream));
de530aaa 1977 stream.next_out = buffer;
39eea7bd 1978 stream.avail_out = size + 1;
de530aaa 1979
39c68542 1980 git_inflate_init(&stream);
079afb18 1981 do {
2b87c45b 1982 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18 1983 stream.next_in = in;
39c68542 1984 st = git_inflate(&stream, Z_FINISH);
39eea7bd
JH
1985 if (!stream.avail_out)
1986 break; /* the payload is larger than it should be */
2b87c45b 1987 curpos += stream.next_in - in;
079afb18 1988 } while (st == Z_OK || st == Z_BUF_ERROR);
39c68542 1989 git_inflate_end(&stream);
de530aaa
SP
1990 if ((st != Z_STREAM_END) || stream.total_out != size) {
1991 free(buffer);
1992 return NULL;
1993 }
1994
1995 return buffer;
1996}
1997
e5e01619
LT
1998#define MAX_DELTA_CACHE (256)
1999
18bdec11 2000static size_t delta_base_cached;
5e08ecbf
NP
2001
2002static struct delta_base_cache_lru_list {
2003 struct delta_base_cache_lru_list *prev;
2004 struct delta_base_cache_lru_list *next;
2005} delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru };
2006
e5e01619 2007static struct delta_base_cache_entry {
5e08ecbf
NP
2008 struct delta_base_cache_lru_list lru;
2009 void *data;
e5e01619
LT
2010 struct packed_git *p;
2011 off_t base_offset;
2012 unsigned long size;
e5e01619
LT
2013 enum object_type type;
2014} delta_base_cache[MAX_DELTA_CACHE];
2015
2016static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
2017{
2018 unsigned long hash;
2019
2020 hash = (unsigned long)p + (unsigned long)base_offset;
2021 hash += (hash >> 8) + (hash >> 16);
3358004a 2022 return hash % MAX_DELTA_CACHE;
e5e01619
LT
2023}
2024
84dd81c1
TR
2025static struct delta_base_cache_entry *
2026get_delta_base_cache_entry(struct packed_git *p, off_t base_offset)
5266d369
JH
2027{
2028 unsigned long hash = pack_entry_hash(p, base_offset);
84dd81c1
TR
2029 return delta_base_cache + hash;
2030}
2031
2032static int eq_delta_base_cache_entry(struct delta_base_cache_entry *ent,
2033 struct packed_git *p, off_t base_offset)
2034{
5266d369
JH
2035 return (ent->data && ent->p == p && ent->base_offset == base_offset);
2036}
2037
84dd81c1
TR
2038static int in_delta_base_cache(struct packed_git *p, off_t base_offset)
2039{
2040 struct delta_base_cache_entry *ent;
2041 ent = get_delta_base_cache_entry(p, base_offset);
2042 return eq_delta_base_cache_entry(ent, p, base_offset);
2043}
2044
2045static void clear_delta_base_cache_entry(struct delta_base_cache_entry *ent)
2046{
2047 ent->data = NULL;
2048 ent->lru.next->prev = ent->lru.prev;
2049 ent->lru.prev->next = ent->lru.next;
2050 delta_base_cached -= ent->size;
2051}
2052
62f255ad 2053static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
a0cba108 2054 unsigned long *base_size, enum object_type *type, int keep_cache)
62f255ad 2055{
84dd81c1 2056 struct delta_base_cache_entry *ent;
e5e01619 2057 void *ret;
e5e01619 2058
84dd81c1
TR
2059 ent = get_delta_base_cache_entry(p, base_offset);
2060
2061 if (!eq_delta_base_cache_entry(ent, p, base_offset))
749bc58c 2062 return unpack_entry(p, base_offset, type, base_size);
e5e01619 2063
84dd81c1
TR
2064 ret = ent->data;
2065
2066 if (!keep_cache)
2067 clear_delta_base_cache_entry(ent);
2068 else
182af834 2069 ret = xmemdupz(ent->data, ent->size);
e5e01619
LT
2070 *type = ent->type;
2071 *base_size = ent->size;
2072 return ret;
62f255ad
LT
2073}
2074
18bdec11
SP
2075static inline void release_delta_base_cache(struct delta_base_cache_entry *ent)
2076{
2077 if (ent->data) {
2078 free(ent->data);
2079 ent->data = NULL;
5e08ecbf
NP
2080 ent->lru.next->prev = ent->lru.prev;
2081 ent->lru.prev->next = ent->lru.next;
18bdec11
SP
2082 delta_base_cached -= ent->size;
2083 }
2084}
2085
3d20c636
SP
2086void clear_delta_base_cache(void)
2087{
2088 unsigned long p;
2089 for (p = 0; p < MAX_DELTA_CACHE; p++)
2090 release_delta_base_cache(&delta_base_cache[p]);
2091}
2092
62f255ad
LT
2093static void add_delta_base_cache(struct packed_git *p, off_t base_offset,
2094 void *base, unsigned long base_size, enum object_type type)
2095{
5e08ecbf 2096 unsigned long hash = pack_entry_hash(p, base_offset);
e5e01619 2097 struct delta_base_cache_entry *ent = delta_base_cache + hash;
5e08ecbf 2098 struct delta_base_cache_lru_list *lru;
e5e01619 2099
18bdec11
SP
2100 release_delta_base_cache(ent);
2101 delta_base_cached += base_size;
5e08ecbf
NP
2102
2103 for (lru = delta_base_cache_lru.next;
2104 delta_base_cached > delta_base_cache_limit
2105 && lru != &delta_base_cache_lru;
2106 lru = lru->next) {
2107 struct delta_base_cache_entry *f = (void *)lru;
18bdec11
SP
2108 if (f->type == OBJ_BLOB)
2109 release_delta_base_cache(f);
2110 }
5e08ecbf
NP
2111 for (lru = delta_base_cache_lru.next;
2112 delta_base_cached > delta_base_cache_limit
2113 && lru != &delta_base_cache_lru;
2114 lru = lru->next) {
2115 struct delta_base_cache_entry *f = (void *)lru;
2116 release_delta_base_cache(f);
2117 }
18bdec11 2118
e5e01619
LT
2119 ent->p = p;
2120 ent->base_offset = base_offset;
2121 ent->type = type;
2122 ent->data = base;
2123 ent->size = base_size;
5e08ecbf
NP
2124 ent->lru.next = &delta_base_cache_lru;
2125 ent->lru.prev = delta_base_cache_lru.prev;
2126 delta_base_cache_lru.prev->next = &ent->lru;
2127 delta_base_cache_lru.prev = &ent->lru;
62f255ad
LT
2128}
2129
c2c5b270
CC
2130static void *read_object(const unsigned char *sha1, enum object_type *type,
2131 unsigned long *size);
2132
5f44324d
JH
2133static void write_pack_access_log(struct packed_git *p, off_t obj_offset)
2134{
67dc598e
KB
2135 static struct trace_key pack_access = TRACE_KEY_INIT(PACK_ACCESS);
2136 trace_printf_key(&pack_access, "%s %"PRIuMAX"\n",
2137 p->pack_name, (uintmax_t)obj_offset);
5f44324d
JH
2138}
2139
0e8189e2
NP
2140int do_check_packed_object_crc;
2141
abe601bb
TR
2142#define UNPACK_ENTRY_STACK_PREALLOC 64
2143struct unpack_entry_stack_ent {
2144 off_t obj_offset;
2145 off_t curpos;
2146 unsigned long size;
2147};
2148
c4001d92 2149void *unpack_entry(struct packed_git *p, off_t obj_offset,
abe601bb 2150 enum object_type *final_type, unsigned long *final_size)
1f688557 2151{
03e79c88 2152 struct pack_window *w_curs = NULL;
c4001d92 2153 off_t curpos = obj_offset;
abe601bb
TR
2154 void *data = NULL;
2155 unsigned long size;
2156 enum object_type type;
2157 struct unpack_entry_stack_ent small_delta_stack[UNPACK_ENTRY_STACK_PREALLOC];
2158 struct unpack_entry_stack_ent *delta_stack = small_delta_stack;
2159 int delta_stack_nr = 0, delta_stack_alloc = UNPACK_ENTRY_STACK_PREALLOC;
2160 int base_from_cache = 0;
1f688557 2161
67dc598e 2162 write_pack_access_log(p, obj_offset);
5f44324d 2163
abe601bb
TR
2164 /* PHASE 1: drill down to the innermost base object */
2165 for (;;) {
2166 off_t base_offset;
2167 int i;
2168 struct delta_base_cache_entry *ent;
2169
77965f8b
NTND
2170 ent = get_delta_base_cache_entry(p, curpos);
2171 if (eq_delta_base_cache_entry(ent, p, curpos)) {
2172 type = ent->type;
2173 data = ent->data;
2174 size = ent->size;
2175 clear_delta_base_cache_entry(ent);
2176 base_from_cache = 1;
2177 break;
2178 }
2179
abe601bb
TR
2180 if (do_check_packed_object_crc && p->index_version > 1) {
2181 struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
2182 unsigned long len = revidx[1].offset - obj_offset;
2183 if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) {
2184 const unsigned char *sha1 =
2185 nth_packed_object_sha1(p, revidx->nr);
2186 error("bad packed object CRC for %s",
2187 sha1_to_hex(sha1));
2188 mark_bad_packed_object(p, sha1);
2189 unuse_pack(&w_curs);
2190 return NULL;
2191 }
2192 }
2193
abe601bb
TR
2194 type = unpack_object_header(p, &w_curs, &curpos, &size);
2195 if (type != OBJ_OFS_DELTA && type != OBJ_REF_DELTA)
2196 break;
2197
2198 base_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
2199 if (!base_offset) {
2200 error("failed to validate delta base reference "
2201 "at offset %"PRIuMAX" from %s",
2202 (uintmax_t)curpos, p->pack_name);
2203 /* bail to phase 2, in hopes of recovery */
2204 data = NULL;
2205 break;
2206 }
2207
2208 /* push object, proceed to base */
2209 if (delta_stack_nr >= delta_stack_alloc
2210 && delta_stack == small_delta_stack) {
2211 delta_stack_alloc = alloc_nr(delta_stack_nr);
2212 delta_stack = xmalloc(sizeof(*delta_stack)*delta_stack_alloc);
2213 memcpy(delta_stack, small_delta_stack,
2214 sizeof(*delta_stack)*delta_stack_nr);
2215 } else {
2216 ALLOC_GROW(delta_stack, delta_stack_nr+1, delta_stack_alloc);
2217 }
2218 i = delta_stack_nr++;
2219 delta_stack[i].obj_offset = obj_offset;
2220 delta_stack[i].curpos = curpos;
2221 delta_stack[i].size = size;
2222
2223 curpos = obj_offset = base_offset;
0e8189e2
NP
2224 }
2225
abe601bb
TR
2226 /* PHASE 2: handle the base */
2227 switch (type) {
eb32d236
NP
2228 case OBJ_OFS_DELTA:
2229 case OBJ_REF_DELTA:
abe601bb
TR
2230 if (data)
2231 die("BUG in unpack_entry: left loop at a valid delta");
4d703a1a 2232 break;
a733cb60 2233 case OBJ_COMMIT:
a733cb60 2234 case OBJ_TREE:
a733cb60 2235 case OBJ_BLOB:
a733cb60 2236 case OBJ_TAG:
abe601bb
TR
2237 if (!base_from_cache)
2238 data = unpack_compressed_entry(p, &w_curs, curpos, size);
4d703a1a 2239 break;
1f688557 2240 default:
8eca0b47
NP
2241 data = NULL;
2242 error("unknown object type %i at offset %"PRIuMAX" in %s",
abe601bb
TR
2243 type, (uintmax_t)obj_offset, p->pack_name);
2244 }
2245
2246 /* PHASE 3: apply deltas in order */
2247
2248 /* invariants:
2249 * 'data' holds the base data, or NULL if there was corruption
2250 */
2251 while (delta_stack_nr) {
2252 void *delta_data;
2253 void *base = data;
2254 unsigned long delta_size, base_size = size;
2255 int i;
2256
2257 data = NULL;
2258
2259 if (base)
2260 add_delta_base_cache(p, obj_offset, base, base_size, type);
2261
2262 if (!base) {
2263 /*
2264 * We're probably in deep shit, but let's try to fetch
2265 * the required base anyway from another pack or loose.
2266 * This is costly but should happen only in the presence
2267 * of a corrupted pack, and is better than failing outright.
2268 */
2269 struct revindex_entry *revidx;
2270 const unsigned char *base_sha1;
2271 revidx = find_pack_revindex(p, obj_offset);
2272 if (revidx) {
2273 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
2274 error("failed to read delta base object %s"
2275 " at offset %"PRIuMAX" from %s",
2276 sha1_to_hex(base_sha1), (uintmax_t)obj_offset,
2277 p->pack_name);
2278 mark_bad_packed_object(p, base_sha1);
2279 base = read_object(base_sha1, &type, &base_size);
2280 }
2281 }
2282
2283 i = --delta_stack_nr;
2284 obj_offset = delta_stack[i].obj_offset;
2285 curpos = delta_stack[i].curpos;
2286 delta_size = delta_stack[i].size;
2287
2288 if (!base)
2289 continue;
2290
2291 delta_data = unpack_compressed_entry(p, &w_curs, curpos, delta_size);
2292
2293 if (!delta_data) {
2294 error("failed to unpack compressed delta "
2295 "at offset %"PRIuMAX" from %s",
2296 (uintmax_t)curpos, p->pack_name);
abe601bb
TR
2297 data = NULL;
2298 continue;
2299 }
2300
2301 data = patch_delta(base, base_size,
2302 delta_data, delta_size,
2303 &size);
1ee886c1
JK
2304
2305 /*
2306 * We could not apply the delta; warn the user, but keep going.
2307 * Our failure will be noticed either in the next iteration of
2308 * the loop, or if this is the final delta, in the caller when
2309 * we return NULL. Those code paths will take care of making
2310 * a more explicit warning and retrying with another copy of
2311 * the object.
2312 */
abe601bb 2313 if (!data)
1ee886c1 2314 error("failed to apply delta");
abe601bb 2315
4b8f772c 2316 free(delta_data);
1f688557 2317 }
abe601bb
TR
2318
2319 *final_type = type;
2320 *final_size = size;
2321
03e79c88 2322 unuse_pack(&w_curs);
019d1e65
NTND
2323
2324 if (delta_stack != small_delta_stack)
2325 free(delta_stack);
2326
21666f1a 2327 return data;
1f688557
JH
2328}
2329
d079837e 2330const unsigned char *nth_packed_object_sha1(struct packed_git *p,
d72308e0 2331 uint32_t n)
9a217f2a 2332{
42873078 2333 const unsigned char *index = p->index_data;
d079837e
SP
2334 if (!index) {
2335 if (open_pack_index(p))
2336 return NULL;
2337 index = p->index_data;
2338 }
57059091 2339 if (n >= p->num_objects)
d72308e0 2340 return NULL;
74e34e1f
NP
2341 index += 4 * 256;
2342 if (p->index_version == 1) {
2343 return index + 24 * n + 4;
2344 } else {
2345 index += 8;
2346 return index + 20 * n;
2347 }
2348}
2349
99093238 2350off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
74e34e1f
NP
2351{
2352 const unsigned char *index = p->index_data;
2353 index += 4 * 256;
2354 if (p->index_version == 1) {
2355 return ntohl(*((uint32_t *)(index + 24 * n)));
2356 } else {
2357 uint32_t off;
2358 index += 8 + p->num_objects * (20 + 4);
2359 off = ntohl(*((uint32_t *)(index + 4 * n)));
2360 if (!(off & 0x80000000))
2361 return off;
2362 index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
2363 return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
2364 ntohl(*((uint32_t *)(index + 4)));
2365 }
9a217f2a
JH
2366}
2367
c4001d92 2368off_t find_pack_entry_one(const unsigned char *sha1,
43057304 2369 struct packed_git *p)
1f688557 2370{
42873078 2371 const uint32_t *level1_ofs = p->index_data;
42873078 2372 const unsigned char *index = p->index_data;
628522ec
JH
2373 unsigned hi, lo, stride;
2374 static int use_lookup = -1;
2375 static int debug_lookup = -1;
2376
2377 if (debug_lookup < 0)
2378 debug_lookup = !!getenv("GIT_DEBUG_LOOKUP");
42873078 2379
d079837e
SP
2380 if (!index) {
2381 if (open_pack_index(p))
2382 return 0;
2383 level1_ofs = p->index_data;
2384 index = p->index_data;
2385 }
74e34e1f
NP
2386 if (p->index_version > 1) {
2387 level1_ofs += 2;
2388 index += 8;
2389 }
42873078 2390 index += 4 * 256;
74e34e1f
NP
2391 hi = ntohl(level1_ofs[*sha1]);
2392 lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
628522ec
JH
2393 if (p->index_version > 1) {
2394 stride = 20;
2395 } else {
2396 stride = 24;
2397 index += 4;
2398 }
2399
2400 if (debug_lookup)
6e1c2344 2401 printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n",
628522ec
JH
2402 sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects);
2403
2404 if (use_lookup < 0)
2405 use_lookup = !!getenv("GIT_USE_LOOKUP");
2406 if (use_lookup) {
2407 int pos = sha1_entry_pos(index, stride, 0,
2408 lo, hi, p->num_objects, sha1);
2409 if (pos < 0)
2410 return 0;
2411 return nth_packed_object_offset(p, pos);
2412 }
1f688557
JH
2413
2414 do {
74e34e1f 2415 unsigned mi = (lo + hi) / 2;
628522ec
JH
2416 int cmp = hashcmp(index + mi * stride, sha1);
2417
2418 if (debug_lookup)
2419 printf("lo %u hi %u rg %u mi %u\n",
2420 lo, hi, hi - lo, mi);
43057304 2421 if (!cmp)
74e34e1f 2422 return nth_packed_object_offset(p, mi);
1f688557
JH
2423 if (cmp > 0)
2424 hi = mi;
2425 else
2426 lo = mi+1;
2427 } while (lo < hi);
2428 return 0;
2429}
2430
4c080182 2431int is_pack_valid(struct packed_git *p)
d131b7af
SP
2432{
2433 /* An already open pack is known to be valid. */
2434 if (p->pack_fd != -1)
2435 return 1;
2436
2437 /* If the pack has one window completely covering the
2438 * file size, the pack is known to be valid even if
2439 * the descriptor is not currently open.
2440 */
2441 if (p->windows) {
2442 struct pack_window *w = p->windows;
2443
2444 if (!w->offset && w->len == p->pack_size)
2445 return 1;
2446 }
2447
2448 /* Force the pack to open to prove its valid. */
2449 return !open_packed_git(p);
2450}
2451
95099731
NTND
2452static int fill_pack_entry(const unsigned char *sha1,
2453 struct pack_entry *e,
2454 struct packed_git *p)
2455{
2456 off_t offset;
2457
2458 if (p->num_bad_objects) {
2459 unsigned i;
2460 for (i = 0; i < p->num_bad_objects; i++)
2461 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
2462 return 0;
2463 }
2464
2465 offset = find_pack_entry_one(sha1, p);
2466 if (!offset)
2467 return 0;
2468
2469 /*
2470 * We are about to tell the caller where they can locate the
2471 * requested object. We better make sure the packfile is
2472 * still here and can be accessed before supplying that
2473 * answer, as it may have been deleted since the index was
2474 * loaded!
2475 */
2476 if (!is_pack_valid(p)) {
2477 warning("packfile %s cannot be accessed", p->pack_name);
2478 return 0;
2479 }
2480 e->offset = offset;
2481 e->p = p;
2482 hashcpy(e->sha1, sha1);
2483 return 1;
2484}
2485
d40d535b
MH
2486/*
2487 * Iff a pack file contains the object named by sha1, return true and
2488 * store its location to e.
2489 */
4d6acb70 2490static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1f688557
JH
2491{
2492 struct packed_git *p;
43057304 2493
1f688557 2494 prepare_packed_git();
f7c22cc6
NP
2495 if (!packed_git)
2496 return 0;
1f688557 2497
c01f51cc
NTND
2498 if (last_found_pack && fill_pack_entry(sha1, e, last_found_pack))
2499 return 1;
8eca0b47 2500
c01f51cc 2501 for (p = packed_git; p; p = p->next) {
1b1005d1
MH
2502 if (p == last_found_pack)
2503 continue; /* we already checked this one */
f7c22cc6 2504
1b1005d1
MH
2505 if (fill_pack_entry(sha1, e, p)) {
2506 last_found_pack = p;
2507 return 1;
2508 }
c01f51cc 2509 }
1f688557
JH
2510 return 0;
2511}
2512
a6080a0a 2513struct packed_git *find_sha1_pack(const unsigned char *sha1,
bf592c50
DB
2514 struct packed_git *packs)
2515{
2516 struct packed_git *p;
bf592c50
DB
2517
2518 for (p = packs; p; p = p->next) {
43057304 2519 if (find_pack_entry_one(sha1, p))
bf592c50
DB
2520 return p;
2521 }
2522 return NULL;
21666f1a 2523
bf592c50
DB
2524}
2525
052fe5ea 2526static int sha1_loose_object_info(const unsigned char *sha1,
23c339c0 2527 struct object_info *oi)
65c2e0c3 2528{
36e4d74a 2529 int status;
65c2e0c3
JH
2530 unsigned long mapsize, size;
2531 void *map;
ef49a7a0 2532 git_zstream stream;
d65a16f6 2533 char hdr[32];
65c2e0c3 2534
5d642e75
JK
2535 if (oi->delta_base_sha1)
2536 hashclr(oi->delta_base_sha1);
2537
052fe5ea
JK
2538 /*
2539 * If we don't care about type or size, then we don't
4ef8d1dd
JH
2540 * need to look inside the object at all. Note that we
2541 * do not optimize out the stat call, even if the
2542 * caller doesn't care about the disk-size, since our
2543 * return value implicitly indicates whether the
2544 * object even exists.
052fe5ea 2545 */
23c339c0 2546 if (!oi->typep && !oi->sizep) {
4ef8d1dd
JH
2547 struct stat st;
2548 if (stat_sha1_file(sha1, &st) < 0)
2549 return -1;
2550 if (oi->disk_sizep)
23c339c0 2551 *oi->disk_sizep = st.st_size;
052fe5ea
JK
2552 return 0;
2553 }
2554
bb6b8e4f 2555 map = map_sha1_file(sha1, &mapsize);
f0df4ed5 2556 if (!map)
dbea72a8 2557 return -1;
23c339c0
JK
2558 if (oi->disk_sizep)
2559 *oi->disk_sizep = mapsize;
36e4d74a
JH
2560 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
2561 status = error("unable to unpack %s header",
2562 sha1_to_hex(sha1));
21666f1a 2563 else if ((status = parse_sha1_header(hdr, &size)) < 0)
36e4d74a 2564 status = error("unable to parse %s header", sha1_to_hex(sha1));
23c339c0
JK
2565 else if (oi->sizep)
2566 *oi->sizep = size;
39c68542 2567 git_inflate_end(&stream);
65c2e0c3 2568 munmap(map, mapsize);
23c339c0
JK
2569 if (oi->typep)
2570 *oi->typep = status;
052fe5ea 2571 return 0;
65c2e0c3
JH
2572}
2573
de7b5d62 2574int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi, unsigned flags)
f0df4ed5 2575{
c4d9986f 2576 struct cached_object *co;
f0df4ed5 2577 struct pack_entry e;
5b086407 2578 int rtype;
1f7117ef 2579 const unsigned char *real = lookup_replace_object_extended(sha1, flags);
f0df4ed5 2580
1f7117ef 2581 co = find_cached_object(real);
c4d9986f 2582 if (co) {
5b086407
JK
2583 if (oi->typep)
2584 *(oi->typep) = co->type;
9a490590
JH
2585 if (oi->sizep)
2586 *(oi->sizep) = co->size;
161f00e7
JK
2587 if (oi->disk_sizep)
2588 *(oi->disk_sizep) = 0;
5d642e75
JK
2589 if (oi->delta_base_sha1)
2590 hashclr(oi->delta_base_sha1);
9a490590 2591 oi->whence = OI_CACHED;
5b086407 2592 return 0;
c4d9986f
NTND
2593 }
2594
1f7117ef 2595 if (!find_pack_entry(real, &e)) {
ddd63e64 2596 /* Most likely it's a loose object. */
1f7117ef 2597 if (!sha1_loose_object_info(real, oi)) {
9a490590 2598 oi->whence = OI_LOOSE;
5b086407 2599 return 0;
9a490590 2600 }
ddd63e64
SG
2601
2602 /* Not a loose object; someone else may have just packed it. */
f0df4ed5 2603 reprepare_packed_git();
1f7117ef 2604 if (!find_pack_entry(real, &e))
052fe5ea 2605 return -1;
f0df4ed5 2606 }
3d77d877 2607
23c339c0 2608 rtype = packed_object_info(e.p, e.offset, oi);
412916ee 2609 if (rtype < 0) {
1f7117ef
CC
2610 mark_bad_packed_object(e.p, real);
2611 return sha1_object_info_extended(real, oi, 0);
5266d369
JH
2612 } else if (in_delta_base_cache(e.p, e.offset)) {
2613 oi->whence = OI_DBCACHED;
9a490590
JH
2614 } else {
2615 oi->whence = OI_PACKED;
2616 oi->u.packed.offset = e.offset;
2617 oi->u.packed.pack = e.p;
2618 oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
2619 rtype == OBJ_OFS_DELTA);
3d77d877
NP
2620 }
2621
5b086407 2622 return 0;
f0df4ed5
JS
2623}
2624
3fc0dca9 2625/* returns enum object_type or negative */
9a490590
JH
2626int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
2627{
5b086407 2628 enum object_type type;
d099b717 2629 struct object_info oi = {NULL};
9a490590 2630
5b086407 2631 oi.typep = &type;
9a490590 2632 oi.sizep = sizep;
de7b5d62 2633 if (sha1_object_info_extended(sha1, &oi, LOOKUP_REPLACE_OBJECT) < 0)
5b086407
JK
2634 return -1;
2635 return type;
9a490590
JH
2636}
2637
21666f1a
NP
2638static void *read_packed_sha1(const unsigned char *sha1,
2639 enum object_type *type, unsigned long *size)
1f688557
JH
2640{
2641 struct pack_entry e;
8eca0b47 2642 void *data;
1f688557 2643
cd673c1f 2644 if (!find_pack_entry(sha1, &e))
1f688557 2645 return NULL;
8eca0b47
NP
2646 data = cache_or_unpack_entry(e.p, e.offset, size, type, 1);
2647 if (!data) {
2648 /*
2649 * We're probably in deep shit, but let's try to fetch
2650 * the required object anyway from another pack or loose.
2651 * This should happen only in the presence of a corrupted
2652 * pack, and is better than failing outright.
2653 */
2654 error("failed to read object %s at offset %"PRIuMAX" from %s",
2655 sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name);
2656 mark_bad_packed_object(e.p, sha1);
ac939109 2657 data = read_object(sha1, type, size);
8eca0b47
NP
2658 }
2659 return data;
1f688557
JH
2660}
2661
21666f1a
NP
2662int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
2663 unsigned char *sha1)
d66b37bb
JH
2664{
2665 struct cached_object *co;
2666
21666f1a 2667 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
2668 if (has_sha1_file(sha1) || find_cached_object(sha1))
2669 return 0;
c7353967 2670 ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
d66b37bb
JH
2671 co = &cached_objects[cached_object_nr++];
2672 co->size = len;
21666f1a 2673 co->type = type;
efa13f7b
JH
2674 co->buf = xmalloc(len);
2675 memcpy(co->buf, buf, len);
d66b37bb
JH
2676 hashcpy(co->sha1, sha1);
2677 return 0;
2678}
2679
c2c5b270
CC
2680static void *read_object(const unsigned char *sha1, enum object_type *type,
2681 unsigned long *size)
0fcfd160
LT
2682{
2683 unsigned long mapsize;
2684 void *map, *buf;
d66b37bb
JH
2685 struct cached_object *co;
2686
2687 co = find_cached_object(sha1);
2688 if (co) {
21666f1a 2689 *type = co->type;
d66b37bb 2690 *size = co->size;
182af834 2691 return xmemdupz(co->buf, co->size);
d66b37bb 2692 }
0fcfd160 2693
8276c007
PE
2694 buf = read_packed_sha1(sha1, type, size);
2695 if (buf)
2696 return buf;
bb6b8e4f 2697 map = map_sha1_file(sha1, &mapsize);
0fcfd160 2698 if (map) {
7efbff75 2699 buf = unpack_sha1_file(map, mapsize, type, size, sha1);
0fcfd160
LT
2700 munmap(map, mapsize);
2701 return buf;
2702 }
637cdd9d 2703 reprepare_packed_git();
8276c007 2704 return read_packed_sha1(sha1, type, size);
0fcfd160
LT
2705}
2706
b6c4cecc
JH
2707/*
2708 * This function dies on corrupt objects; the callers who want to
2709 * deal with them should arrange to call read_object() and give error
2710 * messages themselves.
2711 */
5bf29b95
JH
2712void *read_sha1_file_extended(const unsigned char *sha1,
2713 enum object_type *type,
2714 unsigned long *size,
2715 unsigned flag)
ac939109 2716{
3ba7a065 2717 void *data;
b6c4cecc 2718 const struct packed_git *p;
bf93eea0 2719 const unsigned char *repl = lookup_replace_object_extended(sha1, flag);
b6c4cecc 2720
3ba7a065
JH
2721 errno = 0;
2722 data = read_object(repl, type, size);
4bbf5a26 2723 if (data)
b6c4cecc 2724 return data;
68095570 2725
25f3af3f 2726 if (errno && errno != ENOENT)
3ba7a065
JH
2727 die_errno("failed to read object %s", sha1_to_hex(sha1));
2728
68095570 2729 /* die if we replaced an object with one that does not exist */
b6c4cecc 2730 if (repl != sha1)
68095570
CC
2731 die("replacement %s not found for %s",
2732 sha1_to_hex(repl), sha1_to_hex(sha1));
2733
b6c4cecc 2734 if (has_loose_object(repl)) {
30d6c6ea
MH
2735 const char *path = sha1_file_name(sha1);
2736
b6c4cecc
JH
2737 die("loose object %s (stored in %s) is corrupt",
2738 sha1_to_hex(repl), path);
e8b15e61 2739 }
68095570 2740
b6c4cecc
JH
2741 if ((p = has_packed_and_bad(repl)) != NULL)
2742 die("packed object %s (stored in %s) is corrupt",
2743 sha1_to_hex(repl), p->pack_name);
f5552aee 2744
b6c4cecc 2745 return NULL;
ac939109
NP
2746}
2747
40469ee9 2748void *read_object_with_reference(const unsigned char *sha1,
21666f1a 2749 const char *required_type_name,
40469ee9
JH
2750 unsigned long *size,
2751 unsigned char *actual_sha1_return)
f4913f91 2752{
21666f1a 2753 enum object_type type, required_type;
f4913f91
JH
2754 void *buffer;
2755 unsigned long isize;
40469ee9 2756 unsigned char actual_sha1[20];
f4913f91 2757
21666f1a 2758 required_type = type_from_string(required_type_name);
e702496e 2759 hashcpy(actual_sha1, sha1);
40469ee9
JH
2760 while (1) {
2761 int ref_length = -1;
2762 const char *ref_type = NULL;
f4913f91 2763
21666f1a 2764 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
2765 if (!buffer)
2766 return NULL;
21666f1a 2767 if (type == required_type) {
40469ee9
JH
2768 *size = isize;
2769 if (actual_sha1_return)
e702496e 2770 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
2771 return buffer;
2772 }
2773 /* Handle references */
21666f1a 2774 else if (type == OBJ_COMMIT)
40469ee9 2775 ref_type = "tree ";
21666f1a 2776 else if (type == OBJ_TAG)
40469ee9
JH
2777 ref_type = "object ";
2778 else {
2779 free(buffer);
2780 return NULL;
2781 }
2782 ref_length = strlen(ref_type);
f4913f91 2783
50974ec9
MK
2784 if (ref_length + 40 > isize ||
2785 memcmp(buffer, ref_type, ref_length) ||
1d7f171c 2786 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
2787 free(buffer);
2788 return NULL;
2789 }
1cf58e72 2790 free(buffer);
40469ee9
JH
2791 /* Now we have the ID of the referred-to object in
2792 * actual_sha1. Check again. */
f4913f91 2793 }
f4913f91
JH
2794}
2795
ce9fbf16 2796static void write_sha1_file_prepare(const void *buf, unsigned long len,
972a9155 2797 const char *type, unsigned char *sha1,
d65a16f6 2798 char *hdr, int *hdrlen)
d410c0f5 2799{
9126f009 2800 git_SHA_CTX c;
d410c0f5
JH
2801
2802 /* Generate the header */
d65a16f6 2803 *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
d410c0f5
JH
2804
2805 /* Sha1.. */
9126f009
NP
2806 git_SHA1_Init(&c);
2807 git_SHA1_Update(&c, hdr, *hdrlen);
2808 git_SHA1_Update(&c, buf, len);
2809 git_SHA1_Final(sha1, &c);
d410c0f5
JH
2810}
2811
230f1322 2812/*
5a688fe4
JH
2813 * Move the just written object into its final resting place.
2814 * NEEDSWORK: this should be renamed to finalize_temp_file() as
2815 * "moving" is only a part of what it does, when no patch between
2816 * master to pu changes the call sites of this function.
230f1322 2817 */
839837b9 2818int move_temp_to_file(const char *tmpfile, const char *filename)
230f1322 2819{
e32c0a9c 2820 int ret = 0;
5a688fe4 2821
348df166 2822 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
be66a6c4
JS
2823 goto try_rename;
2824 else if (link(tmpfile, filename))
e32c0a9c 2825 ret = errno;
7ebb6fca
LT
2826
2827 /*
2828 * Coda hack - coda doesn't like cross-directory links,
2829 * so we fall back to a rename, which will mean that it
2830 * won't be able to check collisions, but that's not a
2831 * big deal.
2832 *
2833 * The same holds for FAT formatted media.
2834 *
3be1f18e 2835 * When this succeeds, we just return. We have nothing
7ebb6fca
LT
2836 * left to unlink.
2837 */
2838 if (ret && ret != EEXIST) {
be66a6c4 2839 try_rename:
7ebb6fca 2840 if (!rename(tmpfile, filename))
3be1f18e 2841 goto out;
9e48b389 2842 ret = errno;
230f1322 2843 }
691f1a28 2844 unlink_or_warn(tmpfile);
230f1322
LT
2845 if (ret) {
2846 if (ret != EEXIST) {
82247e9b 2847 return error("unable to write sha1 filename %s: %s", filename, strerror(ret));
230f1322
LT
2848 }
2849 /* FIXME!!! Collision check here ? */
2850 }
2851
3be1f18e 2852out:
5256b006 2853 if (adjust_shared_perm(filename))
5a688fe4 2854 return error("unable to set permission to '%s'", filename);
230f1322
LT
2855 return 0;
2856}
2857
4d548150
LT
2858static int write_buffer(int fd, const void *buf, size_t len)
2859{
d34cf19b 2860 if (write_in_full(fd, buf, len) < 0)
93822c22 2861 return error("file write error (%s)", strerror(errno));
4d548150
LT
2862 return 0;
2863}
2864
ce9fbf16 2865int hash_sha1_file(const void *buf, unsigned long len, const char *type,
abdc3fc8
RS
2866 unsigned char *sha1)
2867{
d65a16f6 2868 char hdr[32];
abdc3fc8
RS
2869 int hdrlen;
2870 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2871 return 0;
2872}
2873
e9039dd3
LT
2874/* Finalize a file on disk, and close it. */
2875static void close_sha1_file(int fd)
2876{
aafe9fba
LT
2877 if (fsync_object_files)
2878 fsync_or_die(fd, "sha1 file");
e9039dd3 2879 if (close(fd) != 0)
d824cbba 2880 die_errno("error when closing sha1 file");
e9039dd3
LT
2881}
2882
5723fe7e
LT
2883/* Size of directory component, including the ending '/' */
2884static inline int directory_size(const char *filename)
2885{
2886 const char *s = strrchr(filename, '/');
2887 if (!s)
2888 return 0;
2889 return s - filename + 1;
2890}
2891
2892/*
2893 * This creates a temporary file in the same directory as the final
2894 * 'filename'
2895 *
2896 * We want to avoid cross-directory filename renames, because those
2897 * can have problems on various filesystems (FAT, NFS, Coda).
2898 */
2899static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename)
2900{
2901 int fd, dirlen = directory_size(filename);
2902
2903 if (dirlen + 20 > bufsiz) {
2904 errno = ENAMETOOLONG;
2905 return -1;
2906 }
2907 memcpy(buffer, filename, dirlen);
2908 strcpy(buffer + dirlen, "tmp_obj_XXXXXX");
5256b006 2909 fd = git_mkstemp_mode(buffer, 0444);
cbacbf4e 2910 if (fd < 0 && dirlen && errno == ENOENT) {
5723fe7e 2911 /* Make sure the directory exists */
6ff6af62 2912 memcpy(buffer, filename, dirlen);
5723fe7e 2913 buffer[dirlen-1] = 0;
b2476a60
JH
2914 if (mkdir(buffer, 0777) && errno != EEXIST)
2915 return -1;
2916 if (adjust_shared_perm(buffer))
5723fe7e
LT
2917 return -1;
2918
2919 /* Try again */
2920 strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX");
5256b006 2921 fd = git_mkstemp_mode(buffer, 0444);
5723fe7e
LT
2922 }
2923 return fd;
2924}
2925
bbac7311 2926static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
c00e657d 2927 const void *buf, unsigned long len, time_t mtime)
0fcfd160 2928{
915308b1 2929 int fd, ret;
9892beba 2930 unsigned char compressed[4096];
ef49a7a0 2931 git_zstream stream;
748af44c
NP
2932 git_SHA_CTX c;
2933 unsigned char parano_sha1[20];
ab1900a3 2934 static char tmp_file[PATH_MAX];
30d6c6ea 2935 const char *filename = sha1_file_name(sha1);
a44c9a5e 2936
ab1900a3 2937 fd = create_tmpfile(tmp_file, sizeof(tmp_file), filename);
aac17941 2938 if (fd < 0) {
35243577 2939 if (errno == EACCES)
82247e9b 2940 return error("insufficient permission for adding an object to repository database %s", get_object_directory());
916d081b 2941 else
5eaeda70 2942 return error("unable to create temporary file: %s", strerror(errno));
aac17941
LT
2943 }
2944
0fcfd160
LT
2945 /* Set it up */
2946 memset(&stream, 0, sizeof(stream));
55bb5c91 2947 git_deflate_init(&stream, zlib_compression_level);
0fcfd160 2948 stream.next_out = compressed;
9892beba 2949 stream.avail_out = sizeof(compressed);
748af44c 2950 git_SHA1_Init(&c);
a44c9a5e
LT
2951
2952 /* First header.. */
d65a16f6 2953 stream.next_in = (unsigned char *)hdr;
a44c9a5e 2954 stream.avail_in = hdrlen;
55bb5c91
JH
2955 while (git_deflate(&stream, 0) == Z_OK)
2956 ; /* nothing */
748af44c 2957 git_SHA1_Update(&c, hdr, hdrlen);
a44c9a5e
LT
2958
2959 /* Then the data itself.. */
c00e657d 2960 stream.next_in = (void *)buf;
a44c9a5e 2961 stream.avail_in = len;
9892beba 2962 do {
748af44c 2963 unsigned char *in0 = stream.next_in;
55bb5c91 2964 ret = git_deflate(&stream, Z_FINISH);
748af44c 2965 git_SHA1_Update(&c, in0, stream.next_in - in0);
9892beba
NP
2966 if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
2967 die("unable to write sha1 file");
2968 stream.next_out = compressed;
2969 stream.avail_out = sizeof(compressed);
2970 } while (ret == Z_OK);
2971
ac54c277
LT
2972 if (ret != Z_STREAM_END)
2973 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
55bb5c91 2974 ret = git_deflate_end_gently(&stream);
ac54c277
LT
2975 if (ret != Z_OK)
2976 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
748af44c
NP
2977 git_SHA1_Final(parano_sha1, &c);
2978 if (hashcmp(sha1, parano_sha1) != 0)
2979 die("confused by unstable object source data for %s", sha1_to_hex(sha1));
ac54c277 2980
e9039dd3 2981 close_sha1_file(fd);
0fcfd160 2982
bbac7311
NP
2983 if (mtime) {
2984 struct utimbuf utb;
2985 utb.actime = mtime;
2986 utb.modtime = mtime;
ab1900a3 2987 if (utime(tmp_file, &utb) < 0)
bbac7311 2988 warning("failed utime() on %s: %s",
ab1900a3 2989 tmp_file, strerror(errno));
bbac7311
NP
2990 }
2991
ab1900a3 2992 return move_temp_to_file(tmp_file, filename);
0fcfd160 2993}
8237b185 2994
33d4221c
JK
2995static int freshen_loose_object(const unsigned char *sha1)
2996{
2997 return check_and_freshen(sha1, 1);
2998}
2999
3000static int freshen_packed_object(const unsigned char *sha1)
3001{
3002 struct pack_entry e;
3003 return find_pack_entry(sha1, &e) && freshen_file(e.p->pack_name);
3004}
3005
c00e657d 3006int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
bbac7311
NP
3007{
3008 unsigned char sha1[20];
3009 char hdr[32];
3010 int hdrlen;
3011
3012 /* Normally if we have it in the pack then we do not bother writing
3013 * it out into .git/objects/??/?{38} file.
3014 */
3015 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
3016 if (returnsha1)
3017 hashcpy(returnsha1, sha1);
33d4221c 3018 if (freshen_loose_object(sha1) || freshen_packed_object(sha1))
bbac7311
NP
3019 return 0;
3020 return write_loose_object(sha1, hdr, hdrlen, buf, len, 0);
3021}
3022
3023int force_object_loose(const unsigned char *sha1, time_t mtime)
3024{
bbac7311
NP
3025 void *buf;
3026 unsigned long len;
3027 enum object_type type;
3028 char hdr[32];
3029 int hdrlen;
1fb23e65 3030 int ret;
bbac7311 3031
c529d75a 3032 if (has_loose_object(sha1))
bbac7311
NP
3033 return 0;
3034 buf = read_packed_sha1(sha1, &type, &len);
3035 if (!buf)
3036 return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
3037 hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
1fb23e65
BS
3038 ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
3039 free(buf);
3040
3041 return ret;
bbac7311
NP
3042}
3043
bf592c50
DB
3044int has_pack_index(const unsigned char *sha1)
3045{
3046 struct stat st;
3047 if (stat(sha1_pack_index_name(sha1), &st))
3048 return 0;
3049 return 1;
bf592c50
DB
3050}
3051
cd673c1f
JH
3052int has_sha1_pack(const unsigned char *sha1)
3053{
3054 struct pack_entry e;
3055 return find_pack_entry(sha1, &e);
3056}
3057
8237b185
DB
3058int has_sha1_file(const unsigned char *sha1)
3059{
1f688557
JH
3060 struct pack_entry e;
3061
cd673c1f 3062 if (find_pack_entry(sha1, &e))
1f688557 3063 return 1;
45e8a748
JK
3064 if (has_loose_object(sha1))
3065 return 1;
3066 reprepare_packed_git();
3067 return find_pack_entry(sha1, &e);
8237b185 3068}
74400e71 3069
c879daa2
NTND
3070static void check_tree(const void *buf, size_t size)
3071{
3072 struct tree_desc desc;
3073 struct name_entry entry;
3074
3075 init_tree_desc(&desc, buf, size);
3076 while (tree_entry(&desc, &entry))
3077 /* do nothing
3078 * tree_entry() will die() on malformed entries */
3079 ;
3080}
3081
3082static void check_commit(const void *buf, size_t size)
3083{
3084 struct commit c;
3085 memset(&c, 0, sizeof(c));
3086 if (parse_commit_buffer(&c, buf, size))
3087 die("corrupt commit");
3088}
3089
3090static void check_tag(const void *buf, size_t size)
3091{
3092 struct tag t;
3093 memset(&t, 0, sizeof(t));
3094 if (parse_tag_buffer(&t, buf, size))
3095 die("corrupt tag");
3096}
3097
43df4f86 3098static int index_mem(unsigned char *sha1, void *buf, size_t size,
c4ce46fc
JH
3099 enum object_type type,
3100 const char *path, unsigned flags)
e7332f96 3101{
6c510bee 3102 int ret, re_allocated = 0;
c4ce46fc 3103 int write_object = flags & HASH_WRITE_OBJECT;
74400e71 3104
7672db20 3105 if (!type)
edaec3fb 3106 type = OBJ_BLOB;
6c510bee
LT
3107
3108 /*
3109 * Convert blobs to git internal format
3110 */
43df4f86 3111 if ((type == OBJ_BLOB) && path) {
f285a2d7 3112 struct strbuf nbuf = STRBUF_INIT;
21e5ad50 3113 if (convert_to_git(path, buf, size, &nbuf,
5e12e78e 3114 write_object ? safe_crlf : SAFE_CRLF_FALSE)) {
b315c5c0 3115 buf = strbuf_detach(&nbuf, &size);
6c510bee
LT
3116 re_allocated = 1;
3117 }
3118 }
c4ce46fc 3119 if (flags & HASH_FORMAT_CHECK) {
c879daa2
NTND
3120 if (type == OBJ_TREE)
3121 check_tree(buf, size);
3122 if (type == OBJ_COMMIT)
3123 check_commit(buf, size);
3124 if (type == OBJ_TAG)
3125 check_tag(buf, size);
3126 }
6c510bee 3127
7672db20 3128 if (write_object)
edaec3fb 3129 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 3130 else
edaec3fb 3131 ret = hash_sha1_file(buf, size, typename(type), sha1);
43df4f86 3132 if (re_allocated)
6c510bee 3133 free(buf);
43df4f86
DP
3134 return ret;
3135}
3136
9035d75a
SP
3137static int index_stream_convert_blob(unsigned char *sha1, int fd,
3138 const char *path, unsigned flags)
3139{
3140 int ret;
3141 const int write_object = flags & HASH_WRITE_OBJECT;
3142 struct strbuf sbuf = STRBUF_INIT;
3143
3144 assert(path);
3145 assert(would_convert_to_git_filter_fd(path));
3146
3147 convert_to_git_filter_fd(path, fd, &sbuf,
3148 write_object ? safe_crlf : SAFE_CRLF_FALSE);
3149
3150 if (write_object)
3151 ret = write_sha1_file(sbuf.buf, sbuf.len, typename(OBJ_BLOB),
3152 sha1);
3153 else
3154 ret = hash_sha1_file(sbuf.buf, sbuf.len, typename(OBJ_BLOB),
3155 sha1);
3156 strbuf_release(&sbuf);
3157 return ret;
3158}
3159
7b41e1e1
JH
3160static int index_pipe(unsigned char *sha1, int fd, enum object_type type,
3161 const char *path, unsigned flags)
3162{
3163 struct strbuf sbuf = STRBUF_INIT;
3164 int ret;
3165
3166 if (strbuf_read(&sbuf, fd, 4096) >= 0)
3167 ret = index_mem(sha1, sbuf.buf, sbuf.len, type, path, flags);
3168 else
3169 ret = -1;
3170 strbuf_release(&sbuf);
3171 return ret;
3172}
3173
ea68b0ce
DP
3174#define SMALL_FILE_SIZE (32*1024)
3175
7b41e1e1
JH
3176static int index_core(unsigned char *sha1, int fd, size_t size,
3177 enum object_type type, const char *path,
3178 unsigned flags)
43df4f86
DP
3179{
3180 int ret;
43df4f86 3181
7b41e1e1 3182 if (!size) {
c4ce46fc 3183 ret = index_mem(sha1, NULL, size, type, path, flags);
ea68b0ce
DP
3184 } else if (size <= SMALL_FILE_SIZE) {
3185 char *buf = xmalloc(size);
3186 if (size == read_in_full(fd, buf, size))
c4ce46fc 3187 ret = index_mem(sha1, buf, size, type, path, flags);
ea68b0ce
DP
3188 else
3189 ret = error("short read %s", strerror(errno));
3190 free(buf);
08bda208 3191 } else {
43df4f86 3192 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
c4ce46fc 3193 ret = index_mem(sha1, buf, size, type, path, flags);
aac17941 3194 munmap(buf, size);
08bda208 3195 }
7b41e1e1
JH
3196 return ret;
3197}
3198
4dd1fbc7 3199/*
568508e7
JH
3200 * This creates one packfile per large blob unless bulk-checkin
3201 * machinery is "plugged".
4dd1fbc7
JH
3202 *
3203 * This also bypasses the usual "convert-to-git" dance, and that is on
3204 * purpose. We could write a streaming version of the converting
3205 * functions and insert that before feeding the data to fast-import
4f22b101
JK
3206 * (or equivalent in-core API described above). However, that is
3207 * somewhat complicated, as we do not know the size of the filter
3208 * result, which we need to know beforehand when writing a git object.
3209 * Since the primary motivation for trying to stream from the working
3210 * tree file and to avoid mmaping it in core is to deal with large
3211 * binary blobs, they generally do not want to get any conversion, and
3212 * callers should avoid this code path when filters are requested.
4dd1fbc7
JH
3213 */
3214static int index_stream(unsigned char *sha1, int fd, size_t size,
3215 enum object_type type, const char *path,
3216 unsigned flags)
3217{
568508e7 3218 return index_bulk_checkin(sha1, fd, size, type, path, flags);
4dd1fbc7
JH
3219}
3220
7b41e1e1
JH
3221int index_fd(unsigned char *sha1, int fd, struct stat *st,
3222 enum object_type type, const char *path, unsigned flags)
3223{
3224 int ret;
7b41e1e1 3225
9079ab7c
SP
3226 /*
3227 * Call xsize_t() only when needed to avoid potentially unnecessary
3228 * die() for large files.
3229 */
9035d75a
SP
3230 if (type == OBJ_BLOB && path && would_convert_to_git_filter_fd(path))
3231 ret = index_stream_convert_blob(sha1, fd, path, flags);
3232 else if (!S_ISREG(st->st_mode))
7b41e1e1 3233 ret = index_pipe(sha1, fd, type, path, flags);
9079ab7c 3234 else if (st->st_size <= big_file_threshold || type != OBJ_BLOB ||
7ce7c760 3235 (path && would_convert_to_git(path)))
9079ab7c
SP
3236 ret = index_core(sha1, fd, xsize_t(st->st_size), type, path,
3237 flags);
4dd1fbc7 3238 else
9079ab7c
SP
3239 ret = index_stream(sha1, fd, xsize_t(st->st_size), type, path,
3240 flags);
43df4f86 3241 close(fd);
aac17941 3242 return ret;
74400e71 3243}
ec1fcc16 3244
c4ce46fc 3245int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags)
ec1fcc16
JH
3246{
3247 int fd;
b760d3aa 3248 struct strbuf sb = STRBUF_INIT;
ec1fcc16
JH
3249
3250 switch (st->st_mode & S_IFMT) {
3251 case S_IFREG:
3252 fd = open(path, O_RDONLY);
3253 if (fd < 0)
3254 return error("open(\"%s\"): %s", path,
3255 strerror(errno));
c4ce46fc 3256 if (index_fd(sha1, fd, st, OBJ_BLOB, path, flags) < 0)
ec1fcc16
JH
3257 return error("%s: failed to insert into database",
3258 path);
3259 break;
3260 case S_IFLNK:
b760d3aa 3261 if (strbuf_readlink(&sb, path, st->st_size)) {
ec1fcc16 3262 char *errstr = strerror(errno);
ec1fcc16
JH
3263 return error("readlink(\"%s\"): %s", path,
3264 errstr);
3265 }
c4ce46fc 3266 if (!(flags & HASH_WRITE_OBJECT))
b760d3aa
LT
3267 hash_sha1_file(sb.buf, sb.len, blob_type, sha1);
3268 else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1))
ec1fcc16
JH
3269 return error("%s: failed to insert into database",
3270 path);
b760d3aa 3271 strbuf_release(&sb);
ec1fcc16 3272 break;
f35a6d3b
LT
3273 case S_IFDIR:
3274 return resolve_gitlink_ref(path, "HEAD", sha1);
ec1fcc16
JH
3275 default:
3276 return error("%s: unsupported file type", path);
3277 }
3278 return 0;
3279}
a69e5429
JH
3280
3281int read_pack_header(int fd, struct pack_header *header)
3282{
c697ad14
HO
3283 if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header))
3284 /* "eof before pack header was fully read" */
3285 return PH_ERROR_EOF;
3286
a69e5429
JH
3287 if (header->hdr_signature != htonl(PACK_SIGNATURE))
3288 /* "protocol error (pack signature mismatch detected)" */
3289 return PH_ERROR_PACK_SIGNATURE;
3290 if (!pack_version_ok(header->hdr_version))
3291 /* "protocol error (pack version unsupported)" */
3292 return PH_ERROR_PROTOCOL;
3293 return 0;
3294}
40d52ff7
JK
3295
3296void assert_sha1_type(const unsigned char *sha1, enum object_type expect)
3297{
3298 enum object_type type = sha1_object_info(sha1, NULL);
3299 if (type < 0)
3300 die("%s is not a valid object", sha1_to_hex(sha1));
3301 if (type != expect)
3302 die("%s is not a valid '%s' object", sha1_to_hex(sha1),
3303 typename(expect));
3304}
27e1e22d
JK
3305
3306static int for_each_file_in_obj_subdir(int subdir_nr,
3307 struct strbuf *path,
3308 each_loose_object_fn obj_cb,
3309 each_loose_cruft_fn cruft_cb,
3310 each_loose_subdir_fn subdir_cb,
3311 void *data)
3312{
3313 size_t baselen = path->len;
3314 DIR *dir = opendir(path->buf);
3315 struct dirent *de;
3316 int r = 0;
3317
3318 if (!dir) {
3319 if (errno == ENOENT)
3320 return 0;
3321 return error("unable to open %s: %s", path->buf, strerror(errno));
3322 }
3323
3324 while ((de = readdir(dir))) {
3325 if (is_dot_or_dotdot(de->d_name))
3326 continue;
3327
3328 strbuf_setlen(path, baselen);
3329 strbuf_addf(path, "/%s", de->d_name);
3330
3331 if (strlen(de->d_name) == 38) {
3332 char hex[41];
3333 unsigned char sha1[20];
3334
3335 snprintf(hex, sizeof(hex), "%02x%s",
3336 subdir_nr, de->d_name);
3337 if (!get_sha1_hex(hex, sha1)) {
3338 if (obj_cb) {
3339 r = obj_cb(sha1, path->buf, data);
3340 if (r)
3341 break;
3342 }
3343 continue;
3344 }
3345 }
3346
3347 if (cruft_cb) {
3348 r = cruft_cb(de->d_name, path->buf, data);
3349 if (r)
3350 break;
3351 }
3352 }
3353 strbuf_setlen(path, baselen);
3354
3355 if (!r && subdir_cb)
3356 r = subdir_cb(subdir_nr, path->buf, data);
3357
3358 closedir(dir);
3359 return r;
3360}
3361
3362int for_each_loose_file_in_objdir(const char *path,
3363 each_loose_object_fn obj_cb,
3364 each_loose_cruft_fn cruft_cb,
3365 each_loose_subdir_fn subdir_cb,
3366 void *data)
3367{
3368 struct strbuf buf = STRBUF_INIT;
3369 size_t baselen;
3370 int r = 0;
3371 int i;
3372
3373 strbuf_addstr(&buf, path);
3374 strbuf_addch(&buf, '/');
3375 baselen = buf.len;
3376
3377 for (i = 0; i < 256; i++) {
3378 strbuf_addf(&buf, "%02x", i);
3379 r = for_each_file_in_obj_subdir(i, &buf, obj_cb, cruft_cb,
3380 subdir_cb, data);
3381 strbuf_setlen(&buf, baselen);
3382 if (r)
3383 break;
3384 }
3385
3386 strbuf_release(&buf);
3387 return r;
3388}
660c889e
JK
3389
3390struct loose_alt_odb_data {
3391 each_loose_object_fn *cb;
3392 void *data;
3393};
3394
3395static int loose_from_alt_odb(struct alternate_object_database *alt,
3396 void *vdata)
3397{
3398 struct loose_alt_odb_data *data = vdata;
3399 return for_each_loose_file_in_objdir(alt->base,
3400 data->cb, NULL, NULL,
3401 data->data);
3402}
3403
3404int for_each_loose_object(each_loose_object_fn cb, void *data)
3405{
3406 struct loose_alt_odb_data alt;
3407 int r;
3408
3409 r = for_each_loose_file_in_objdir(get_object_directory(),
3410 cb, NULL, NULL, data);
3411 if (r)
3412 return r;
3413
3414 alt.cb = cb;
3415 alt.data = data;
3416 return foreach_alt_odb(loose_from_alt_odb, &alt);
3417}
3418
3419static int for_each_object_in_pack(struct packed_git *p, each_packed_object_fn cb, void *data)
3420{
3421 uint32_t i;
3422 int r = 0;
3423
3424 for (i = 0; i < p->num_objects; i++) {
3425 const unsigned char *sha1 = nth_packed_object_sha1(p, i);
3426
3427 if (!sha1)
3428 return error("unable to get sha1 of object %u in %s",
3429 i, p->pack_name);
3430
3431 r = cb(sha1, p, i, data);
3432 if (r)
3433 break;
3434 }
3435 return r;
3436}
3437
3438int for_each_packed_object(each_packed_object_fn cb, void *data)
3439{
3440 struct packed_git *p;
3441 int r = 0;
3442
3443 prepare_packed_git();
3444 for (p = packed_git; p; p = p->next) {
3445 r = for_each_object_in_pack(p, cb, data);
3446 if (r)
3447 break;
3448 }
3449 return r;
3450}