t5570: Update for clone-progress-to-stderr branch
[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"
1f688557 11#include "delta.h"
a733cb60 12#include "pack.h"
8e440259
PE
13#include "blob.h"
14#include "commit.h"
4dd1fbc7 15#include "run-command.h"
8e440259
PE
16#include "tag.h"
17#include "tree.h"
c879daa2 18#include "tree-walk.h"
f35a6d3b 19#include "refs.h"
70f5d5d3 20#include "pack-revindex.h"
628522ec 21#include "sha1-lookup.h"
568508e7 22#include "bulk-checkin.h"
090ea126 23#include "streaming.h"
543c5caa 24#include "dir.h"
0fcfd160 25
144bde78
LT
26#ifndef O_NOATIME
27#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
28#define O_NOATIME 01000000
29#else
30#define O_NOATIME 0
31#endif
32#endif
33
28bd70d8
JN
34#define SZ_FMT PRIuMAX
35static inline uintmax_t sz_fmt(size_t s) { return s; }
e05db0fd 36
96f1e58f 37const unsigned char null_sha1[20];
88cd621d 38
b12ca963
NTND
39static const char *no_log_pack_access = "no_log_pack_access";
40static const char *log_pack_access;
41
c597ba80
NTND
42/*
43 * This is meant to hold a *small* number of objects that you would
44 * want read_sha1_file() to be able to return, but yet you do not want
45 * to write them into the object store (e.g. a browse-only
46 * application).
47 */
48static struct cached_object {
49 unsigned char sha1[20];
50 enum object_type type;
51 void *buf;
52 unsigned long size;
53} *cached_objects;
54static int cached_object_nr, cached_object_alloc;
55
56static struct cached_object empty_tree = {
dab0d410 57 EMPTY_TREE_SHA1_BIN_LITERAL,
c597ba80
NTND
58 OBJ_TREE,
59 "",
60 0
61};
62
c01f51cc
NTND
63static struct packed_git *last_found_pack;
64
c597ba80
NTND
65static struct cached_object *find_cached_object(const unsigned char *sha1)
66{
67 int i;
68 struct cached_object *co = cached_objects;
69
70 for (i = 0; i < cached_object_nr; i++, co++) {
71 if (!hashcmp(co->sha1, sha1))
72 return co;
73 }
74 if (!hashcmp(sha1, empty_tree.sha1))
75 return &empty_tree;
76 return NULL;
77}
78
90a6464b
JH
79int mkdir_in_gitdir(const char *path)
80{
81 if (mkdir(path, 0777)) {
82 int saved_errno = errno;
83 struct stat st;
84 struct strbuf sb = STRBUF_INIT;
85
86 if (errno != EEXIST)
87 return -1;
88 /*
89 * Are we looking at a path in a symlinked worktree
90 * whose original repository does not yet have it?
91 * e.g. .git/rr-cache pointing at its original
92 * repository in which the user hasn't performed any
93 * conflict resolution yet?
94 */
95 if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
96 strbuf_readlink(&sb, path, st.st_size) ||
97 !is_absolute_path(sb.buf) ||
98 mkdir(sb.buf, 0777)) {
99 strbuf_release(&sb);
100 errno = saved_errno;
101 return -1;
102 }
103 strbuf_release(&sb);
104 }
105 return adjust_shared_perm(path);
106}
107
b2cb9425
JH
108int safe_create_leading_directories(char *path)
109{
8385abfd 110 char *pos = path + offset_1st_component(path);
67d42212
JR
111 struct stat st;
112
b2cb9425
JH
113 while (pos) {
114 pos = strchr(pos, '/');
115 if (!pos)
116 break;
5f0bdf50
JH
117 while (*++pos == '/')
118 ;
119 if (!*pos)
120 break;
121 *--pos = '\0';
67d42212
JR
122 if (!stat(path, &st)) {
123 /* path exists */
124 if (!S_ISDIR(st.st_mode)) {
b2cb9425 125 *pos = '/';
67d42212 126 return -3;
b2cb9425 127 }
457f06d6 128 }
67d42212 129 else if (mkdir(path, 0777)) {
928734d9
SW
130 if (errno == EEXIST &&
131 !stat(path, &st) && S_ISDIR(st.st_mode)) {
132 ; /* somebody created it since we checked */
133 } else {
134 *pos = '/';
135 return -1;
136 }
67d42212 137 }
457f06d6
JS
138 else if (adjust_shared_perm(path)) {
139 *pos = '/';
140 return -2;
141 }
b2cb9425
JH
142 *pos++ = '/';
143 }
144 return 0;
145}
723c31fe 146
8e21d63b
JK
147int safe_create_leading_directories_const(const char *path)
148{
149 /* path points to cache entries, so xstrdup before messing with it */
150 char *buf = xstrdup(path);
151 int result = safe_create_leading_directories(buf);
152 free(buf);
153 return result;
154}
155
ace1534d
JH
156static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
157{
158 int i;
159 for (i = 0; i < 20; i++) {
160 static char hex[] = "0123456789abcdef";
161 unsigned int val = sha1[i];
162 char *pos = pathbuf + i*2 + (i > 0);
163 *pos++ = hex[val >> 4];
164 *pos = hex[val & 0xf];
165 }
166}
167
0fcfd160
LT
168/*
169 * NOTE! This returns a statically allocated buffer, so you have to be
790296fd 170 * careful about using it. Do an "xstrdup()" if you need to save the
0fcfd160 171 * filename.
ace1534d
JH
172 *
173 * Also note that this returns the location for creating. Reading
174 * SHA1 file can happen from any alternate directory listed in the
d19938ab 175 * DB_ENVIRONMENT environment variable if it is not found in
ace1534d 176 * the primary object database.
0fcfd160
LT
177 */
178char *sha1_file_name(const unsigned char *sha1)
179{
560fb6a1
JK
180 static char buf[PATH_MAX];
181 const char *objdir;
182 int len;
0fcfd160 183
560fb6a1
JK
184 objdir = get_object_directory();
185 len = strlen(objdir);
186
187 /* '/' + sha1(2) + '/' + sha1(38) + '\0' */
188 if (len + 43 > PATH_MAX)
189 die("insanely long object directory %s", objdir);
190 memcpy(buf, objdir, len);
191 buf[len] = '/';
192 buf[len+3] = '/';
193 buf[len+42] = '\0';
194 fill_sha1_path(buf + len + 1, sha1);
195 return buf;
0fcfd160
LT
196}
197
633f43e1 198static char *sha1_get_pack_name(const unsigned char *sha1,
6eec46bd 199 char **name, char **base, const char *which)
bf592c50
DB
200{
201 static const char hex[] = "0123456789abcdef";
633f43e1 202 char *buf;
bf592c50
DB
203 int i;
204
633f43e1 205 if (!*base) {
bf592c50
DB
206 const char *sha1_file_directory = get_object_directory();
207 int len = strlen(sha1_file_directory);
633f43e1 208 *base = xmalloc(len + 60);
6eec46bd
JH
209 sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
210 sha1_file_directory, which);
633f43e1 211 *name = *base + len + 11;
bf592c50
DB
212 }
213
633f43e1 214 buf = *name;
bf592c50
DB
215
216 for (i = 0; i < 20; i++) {
217 unsigned int val = *sha1++;
218 *buf++ = hex[val >> 4];
219 *buf++ = hex[val & 0xf];
220 }
a6080a0a 221
633f43e1 222 return *base;
bf592c50
DB
223}
224
633f43e1 225char *sha1_pack_name(const unsigned char *sha1)
bf592c50 226{
633f43e1 227 static char *name, *base;
bf592c50 228
6eec46bd 229 return sha1_get_pack_name(sha1, &name, &base, "pack");
633f43e1 230}
bf592c50 231
633f43e1
HO
232char *sha1_pack_index_name(const unsigned char *sha1)
233{
234 static char *name, *base;
a6080a0a 235
6eec46bd 236 return sha1_get_pack_name(sha1, &name, &base, "idx");
bf592c50
DB
237}
238
d5a63b99
JH
239struct alternate_object_database *alt_odb_list;
240static struct alternate_object_database **alt_odb_tail;
ace1534d 241
f4e51683 242static int git_open_noatime(const char *name);
c2f493a4 243
ddd5d056
JH
244/*
245 * Prepare alternate object database registry.
d5a63b99
JH
246 *
247 * The variable alt_odb_list points at the list of struct
248 * alternate_object_database. The elements on this list come from
249 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
250 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
251 * whose contents is similar to that environment variable but can be
252 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
253 * contains "/the/directory/corresponding/to/.git/objects/...", while
254 * its name points just after the slash at the end of ".git/objects/"
255 * in the example above, and has enough space to hold 40-byte hex
256 * SHA1, an extra slash for the first level indirection, and the
257 * terminating NUL.
ddd5d056 258 */
6eac50d8 259static int link_alt_odb_entry(const char *entry, const char *relative_base, int depth)
ace1534d 260{
1494e038 261 const char *objdir = get_object_directory();
c2f493a4
MW
262 struct alternate_object_database *ent;
263 struct alternate_object_database *alt;
5bdf0a84
HW
264 int pfxlen, entlen;
265 struct strbuf pathbuf = STRBUF_INIT;
d5a63b99 266
85dadc38 267 if (!is_absolute_path(entry) && relative_base) {
5bdf0a84
HW
268 strbuf_addstr(&pathbuf, real_path(relative_base));
269 strbuf_addch(&pathbuf, '/');
c2f493a4 270 }
6eac50d8 271 strbuf_addstr(&pathbuf, entry);
c2f493a4 272
5bdf0a84
HW
273 normalize_path_copy(pathbuf.buf, pathbuf.buf);
274
275 pfxlen = strlen(pathbuf.buf);
276
277 /*
278 * The trailing slash after the directory name is given by
279 * this function at the end. Remove duplicates.
280 */
281 while (pfxlen && pathbuf.buf[pfxlen-1] == '/')
282 pfxlen -= 1;
283
284 entlen = pfxlen + 43; /* '/' + 2 hex + '/' + 38 hex + NUL */
285 ent = xmalloc(sizeof(*ent) + entlen);
286 memcpy(ent->base, pathbuf.buf, pfxlen);
287 strbuf_release(&pathbuf);
c2f493a4
MW
288
289 ent->name = ent->base + pfxlen + 1;
290 ent->base[pfxlen + 3] = '/';
291 ent->base[pfxlen] = ent->base[entlen-1] = 0;
292
293 /* Detect cases where alternate disappeared */
90b4a71c 294 if (!is_directory(ent->base)) {
c2f493a4
MW
295 error("object directory %s does not exist; "
296 "check .git/objects/info/alternates.",
297 ent->base);
298 free(ent);
299 return -1;
300 }
301
302 /* Prevent the common mistake of listing the same
303 * thing twice, or object directory itself.
304 */
305 for (alt = alt_odb_list; alt; alt = alt->next) {
306 if (!memcmp(ent->base, alt->base, pfxlen)) {
307 free(ent);
308 return -1;
309 }
310 }
cb2912c3 311 if (!strcmp(ent->base, objdir)) {
c2f493a4
MW
312 free(ent);
313 return -1;
314 }
315
316 /* add the alternate entry */
317 *alt_odb_tail = ent;
318 alt_odb_tail = &(ent->next);
319 ent->next = NULL;
320
321 /* recursively add alternates */
322 read_info_alternates(ent->base, depth + 1);
323
324 ent->base[pfxlen] = '/';
325
326 return 0;
327}
328
c5950164 329static void link_alt_odb_entries(const char *alt, int len, int sep,
c2f493a4
MW
330 const char *relative_base, int depth)
331{
6eac50d8
MH
332 struct string_list entries = STRING_LIST_INIT_NODUP;
333 char *alt_copy;
334 int i;
c2f493a4
MW
335
336 if (depth > 5) {
337 error("%s: ignoring alternate object stores, nesting too deep.",
338 relative_base);
339 return;
340 }
341
c5950164 342 alt_copy = xmemdupz(alt, len);
6eac50d8
MH
343 string_list_split_in_place(&entries, alt_copy, sep, -1);
344 for (i = 0; i < entries.nr; i++) {
345 const char *entry = entries.items[i].string;
346 if (entry[0] == '\0' || entry[0] == '#')
9577e7e3 347 continue;
6eac50d8
MH
348 if (!is_absolute_path(entry) && depth) {
349 error("%s: ignoring relative alternate object store %s",
350 relative_base, entry);
351 } else {
352 link_alt_odb_entry(entry, relative_base, depth);
9577e7e3 353 }
9577e7e3 354 }
6eac50d8
MH
355 string_list_clear(&entries, 0);
356 free(alt_copy);
d5a63b99
JH
357}
358
5e73633d 359void read_info_alternates(const char * relative_base, int depth)
d5a63b99 360{
9577e7e3 361 char *map;
dc49cd76 362 size_t mapsz;
d5a63b99 363 struct stat st;
9cb18f56
JM
364 const char alt_file_name[] = "info/alternates";
365 /* Given that relative_base is no longer than PATH_MAX,
366 ensure that "path" has enough space to append "/", the
367 file name, "info/alternates", and a trailing NUL. */
368 char path[PATH_MAX + 1 + sizeof alt_file_name];
c2f493a4 369 int fd;
d5a63b99 370
9cb18f56 371 sprintf(path, "%s/%s", relative_base, alt_file_name);
f4e51683 372 fd = git_open_noatime(path);
d5a63b99
JH
373 if (fd < 0)
374 return;
375 if (fstat(fd, &st) || (st.st_size == 0)) {
376 close(fd);
9a217f2a 377 return;
ace1534d 378 }
dc49cd76
SP
379 mapsz = xsize_t(st.st_size);
380 map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0);
d5a63b99 381 close(fd);
d5a63b99 382
c5950164 383 link_alt_odb_entries(map, mapsz, '\n', relative_base, depth);
c2f493a4 384
dc49cd76 385 munmap(map, mapsz);
ace1534d
JH
386}
387
bef70b22
DB
388void add_to_alternates_file(const char *reference)
389{
390 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
acd3b9ec 391 int fd = hold_lock_file_for_append(lock, git_path("objects/info/alternates"), LOCK_DIE_ON_ERROR);
e6baf4a1 392 char *alt = mkpath("%s\n", reference);
bef70b22
DB
393 write_or_die(fd, alt, strlen(alt));
394 if (commit_lock_file(lock))
395 die("could not close alternates file");
396 if (alt_odb_tail)
c5950164 397 link_alt_odb_entries(alt, strlen(alt), '\n', NULL, 0);
bef70b22
DB
398}
399
d79796bc
JH
400void foreach_alt_odb(alt_odb_fn fn, void *cb)
401{
402 struct alternate_object_database *ent;
403
404 prepare_alt_odb();
405 for (ent = alt_odb_list; ent; ent = ent->next)
406 if (fn(ent, cb))
407 return;
408}
409
c2f493a4
MW
410void prepare_alt_odb(void)
411{
554fe20d 412 const char *alt;
c2f493a4 413
7dc24aa5
SP
414 if (alt_odb_tail)
415 return;
416
c2f493a4
MW
417 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
418 if (!alt) alt = "";
419
c2f493a4 420 alt_odb_tail = &alt_odb_list;
c5950164 421 link_alt_odb_entries(alt, strlen(alt), PATH_SEP, NULL, 0);
c2f493a4
MW
422
423 read_info_alternates(get_object_directory(), 0);
424}
425
0f4dc14a 426static int has_loose_object_local(const unsigned char *sha1)
ace1534d 427{
ace1534d 428 char *name = sha1_file_name(sha1);
0f4dc14a
BC
429 return !access(name, F_OK);
430}
ace1534d 431
0f4dc14a
BC
432int has_loose_object_nonlocal(const unsigned char *sha1)
433{
434 struct alternate_object_database *alt;
9a217f2a 435 prepare_alt_odb();
d5a63b99 436 for (alt = alt_odb_list; alt; alt = alt->next) {
0f4dc14a 437 fill_sha1_path(alt->name, sha1);
c529d75a
LT
438 if (!access(alt->base, F_OK))
439 return 1;
ace1534d 440 }
c529d75a 441 return 0;
ace1534d
JH
442}
443
0f4dc14a
BC
444static int has_loose_object(const unsigned char *sha1)
445{
446 return has_loose_object_local(sha1) ||
447 has_loose_object_nonlocal(sha1);
448}
449
60bb8b14 450static unsigned int pack_used_ctr;
a53128b6
SP
451static unsigned int pack_mmap_calls;
452static unsigned int peak_pack_open_windows;
453static unsigned int pack_open_windows;
c7934306
SP
454static unsigned int pack_open_fds;
455static unsigned int pack_max_fds;
a53128b6 456static size_t peak_pack_mapped;
60bb8b14 457static size_t pack_mapped;
9a217f2a 458struct packed_git *packed_git;
1f688557 459
b79d18c9 460void pack_report(void)
a53128b6
SP
461{
462 fprintf(stderr,
e05db0fd
PR
463 "pack_report: getpagesize() = %10" SZ_FMT "\n"
464 "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
465 "pack_report: core.packedGitLimit = %10" SZ_FMT "\n",
9e42d6a1
SP
466 sz_fmt(getpagesize()),
467 sz_fmt(packed_git_window_size),
468 sz_fmt(packed_git_limit));
a53128b6
SP
469 fprintf(stderr,
470 "pack_report: pack_used_ctr = %10u\n"
471 "pack_report: pack_mmap_calls = %10u\n"
472 "pack_report: pack_open_windows = %10u / %10u\n"
e05db0fd
PR
473 "pack_report: pack_mapped = "
474 "%10" SZ_FMT " / %10" SZ_FMT "\n",
a53128b6
SP
475 pack_used_ctr,
476 pack_mmap_calls,
477 pack_open_windows, peak_pack_open_windows,
9e42d6a1 478 sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped));
a53128b6
SP
479}
480
42873078 481static int check_packed_git_idx(const char *path, struct packed_git *p)
1f688557
JH
482{
483 void *idx_map;
42873078 484 struct pack_idx_header *hdr;
dc49cd76 485 size_t idx_size;
74e34e1f 486 uint32_t version, nr, i, *index;
f4e51683 487 int fd = git_open_noatime(path);
1f688557 488 struct stat st;
42873078 489
1f688557
JH
490 if (fd < 0)
491 return -1;
492 if (fstat(fd, &st)) {
493 close(fd);
494 return -1;
495 }
dc49cd76 496 idx_size = xsize_t(st.st_size);
2d88451b
SP
497 if (idx_size < 4 * 256 + 20 + 20) {
498 close(fd);
499 return error("index file %s is too small", path);
500 }
c4712e45 501 idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
1f688557 502 close(fd);
1f688557 503
42873078
NP
504 hdr = idx_map;
505 if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) {
74e34e1f
NP
506 version = ntohl(hdr->idx_version);
507 if (version < 2 || version > 2) {
508 munmap(idx_map, idx_size);
6e1c2344 509 return error("index file %s is version %"PRIu32
74e34e1f
NP
510 " and is not supported by this binary"
511 " (try upgrading GIT to a newer version)",
512 path, version);
513 }
514 } else
515 version = 1;
df1b059d 516
1f688557 517 nr = 0;
42873078 518 index = idx_map;
74e34e1f
NP
519 if (version > 1)
520 index += 2; /* skip index header */
1f688557 521 for (i = 0; i < 256; i++) {
326bf396 522 uint32_t n = ntohl(index[i]);
2d88451b
SP
523 if (n < nr) {
524 munmap(idx_map, idx_size);
df1b059d 525 return error("non-monotonic index %s", path);
2d88451b 526 }
1f688557
JH
527 nr = n;
528 }
529
74e34e1f
NP
530 if (version == 1) {
531 /*
532 * Total size:
533 * - 256 index entries 4 bytes each
534 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
535 * - 20-byte SHA1 of the packfile
536 * - 20-byte SHA1 file checksum
537 */
538 if (idx_size != 4*256 + nr * 24 + 20 + 20) {
539 munmap(idx_map, idx_size);
eef427a0 540 return error("wrong index v1 file size in %s", path);
74e34e1f
NP
541 }
542 } else if (version == 2) {
543 /*
544 * Minimum size:
545 * - 8 bytes of header
546 * - 256 index entries 4 bytes each
547 * - 20-byte sha1 entry * nr
548 * - 4-byte crc entry * nr
549 * - 4-byte offset entry * nr
550 * - 20-byte SHA1 of the packfile
551 * - 20-byte SHA1 file checksum
552 * And after the 4-byte offset table might be a
553 * variable sized table containing 8-byte entries
554 * for offsets larger than 2^31.
555 */
556 unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20;
1164f1e4
LT
557 unsigned long max_size = min_size;
558 if (nr)
559 max_size += (nr - 1)*8;
560 if (idx_size < min_size || idx_size > max_size) {
74e34e1f 561 munmap(idx_map, idx_size);
eef427a0 562 return error("wrong index v2 file size in %s", path);
74e34e1f 563 }
7109c889
JH
564 if (idx_size != min_size &&
565 /*
566 * make sure we can deal with large pack offsets.
567 * 31-bit signed offset won't be enough, neither
568 * 32-bit unsigned one will be.
569 */
570 (sizeof(off_t) <= 4)) {
571 munmap(idx_map, idx_size);
572 return error("pack too large for current definition of off_t in %s", path);
74e34e1f 573 }
2d88451b 574 }
1f688557 575
74e34e1f 576 p->index_version = version;
42873078
NP
577 p->index_data = idx_map;
578 p->index_size = idx_size;
57059091 579 p->num_objects = nr;
1f688557
JH
580 return 0;
581}
582
bc8e478a 583int open_pack_index(struct packed_git *p)
d079837e
SP
584{
585 char *idx_name;
586 int ret;
587
588 if (p->index_data)
589 return 0;
590
591 idx_name = xstrdup(p->pack_name);
592 strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx");
593 ret = check_packed_git_idx(idx_name, p);
594 free(idx_name);
595 return ret;
596}
597
11daf39b
SP
598static void scan_windows(struct packed_git *p,
599 struct packed_git **lru_p,
600 struct pack_window **lru_w,
601 struct pack_window **lru_l)
1f688557 602{
11daf39b
SP
603 struct pack_window *w, *w_l;
604
605 for (w_l = NULL, w = p->windows; w; w = w->next) {
606 if (!w->inuse_cnt) {
607 if (!*lru_w || w->last_used < (*lru_w)->last_used) {
608 *lru_p = p;
609 *lru_w = w;
610 *lru_l = w_l;
54044bf8 611 }
54044bf8 612 }
11daf39b 613 w_l = w;
f9253394 614 }
11daf39b
SP
615}
616
d1efefa4 617static int unuse_one_window(struct packed_git *current, int keep_fd)
11daf39b
SP
618{
619 struct packed_git *p, *lru_p = NULL;
620 struct pack_window *lru_w = NULL, *lru_l = NULL;
621
622 if (current)
623 scan_windows(current, &lru_p, &lru_w, &lru_l);
624 for (p = packed_git; p; p = p->next)
625 scan_windows(p, &lru_p, &lru_w, &lru_l);
54044bf8
SP
626 if (lru_p) {
627 munmap(lru_w->base, lru_w->len);
628 pack_mapped -= lru_w->len;
629 if (lru_l)
630 lru_l->next = lru_w->next;
631 else {
632 lru_p->windows = lru_w->next;
d131b7af
SP
633 if (!lru_p->windows && lru_p->pack_fd != -1
634 && lru_p->pack_fd != keep_fd) {
54044bf8 635 close(lru_p->pack_fd);
c7934306 636 pack_open_fds--;
54044bf8
SP
637 lru_p->pack_fd = -1;
638 }
639 }
640 free(lru_w);
a53128b6 641 pack_open_windows--;
54044bf8
SP
642 return 1;
643 }
644 return 0;
f9253394
JH
645}
646
d1efefa4 647void release_pack_memory(size_t need, int fd)
97bfeb34
SP
648{
649 size_t cur = pack_mapped;
d1efefa4 650 while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd))
97bfeb34
SP
651 ; /* nothing */
652}
653
58ecbd5e
JN
654void *xmmap(void *start, size_t length,
655 int prot, int flags, int fd, off_t offset)
656{
657 void *ret = mmap(start, length, prot, flags, fd, offset);
658 if (ret == MAP_FAILED) {
659 if (!length)
660 return NULL;
661 release_pack_memory(length, fd);
662 ret = mmap(start, length, prot, flags, fd, offset);
663 if (ret == MAP_FAILED)
664 die_errno("Out of memory? mmap failed");
665 }
666 return ret;
667}
668
c9ced051
SP
669void close_pack_windows(struct packed_git *p)
670{
671 while (p->windows) {
672 struct pack_window *w = p->windows;
673
674 if (w->inuse_cnt)
675 die("pack '%s' still has open windows to it",
676 p->pack_name);
677 munmap(w->base, w->len);
678 pack_mapped -= w->len;
679 pack_open_windows--;
680 p->windows = w->next;
681 free(w);
682 }
683}
684
03e79c88 685void unuse_pack(struct pack_window **w_cursor)
f9253394 686{
03e79c88
SP
687 struct pack_window *w = *w_cursor;
688 if (w) {
689 w->inuse_cnt--;
690 *w_cursor = NULL;
691 }
1f688557
JH
692}
693
fa5fc15d
SP
694void close_pack_index(struct packed_git *p)
695{
696 if (p->index_data) {
697 munmap((void *)p->index_data, p->index_size);
698 p->index_data = NULL;
699 }
700}
701
c74faea1
NP
702/*
703 * This is used by git-repack in case a newly created pack happens to
704 * contain the same set of objects as an existing one. In that case
705 * the resulting file might be different even if its name would be the
706 * same. It is best to close any reference to the old pack before it is
707 * replaced on disk. Of course no index pointers nor windows for given pack
708 * must subsist at this point. If ever objects from this pack are requested
709 * again, the new version of the pack will be reinitialized through
710 * reprepare_packed_git().
711 */
712void free_pack_by_name(const char *pack_name)
713{
714 struct packed_git *p, **pp = &packed_git;
715
716 while (*pp) {
717 p = *pp;
718 if (strcmp(pack_name, p->pack_name) == 0) {
fa3a0c94 719 clear_delta_base_cache();
c74faea1 720 close_pack_windows(p);
c7934306 721 if (p->pack_fd != -1) {
c74faea1 722 close(p->pack_fd);
c7934306
SP
723 pack_open_fds--;
724 }
fa5fc15d 725 close_pack_index(p);
c74faea1
NP
726 free(p->bad_object_sha1);
727 *pp = p->next;
c01f51cc
NTND
728 if (last_found_pack == p)
729 last_found_pack = NULL;
c74faea1
NP
730 free(p);
731 return;
732 }
733 pp = &p->next;
734 }
735}
736
a0788266
JS
737static unsigned int get_max_fd_limit(void)
738{
739#ifdef RLIMIT_NOFILE
740 struct rlimit lim;
741
742 if (getrlimit(RLIMIT_NOFILE, &lim))
743 die_errno("cannot get RLIMIT_NOFILE");
744
745 return lim.rlim_cur;
746#elif defined(_SC_OPEN_MAX)
747 return sysconf(_SC_OPEN_MAX);
748#elif defined(OPEN_MAX)
749 return OPEN_MAX;
750#else
751 return 1; /* see the caller ;-) */
752#endif
753}
754
3cf8b462
SP
755/*
756 * Do not call this directly as this leaks p->pack_fd on error return;
757 * call open_packed_git() instead.
758 */
759static int open_packed_git_1(struct packed_git *p)
1f688557 760{
9bc879c1
SP
761 struct stat st;
762 struct pack_header hdr;
763 unsigned char sha1[20];
764 unsigned char *idx_sha1;
2c039da8 765 long fd_flag;
9bc879c1 766
d079837e
SP
767 if (!p->index_data && open_pack_index(p))
768 return error("packfile %s index unavailable", p->pack_name);
769
c7934306 770 if (!pack_max_fds) {
a0788266 771 unsigned int max_fds = get_max_fd_limit();
c7934306
SP
772
773 /* Save 3 for stdin/stdout/stderr, 22 for work */
774 if (25 < max_fds)
775 pack_max_fds = max_fds - 25;
776 else
777 pack_max_fds = 1;
778 }
779
780 while (pack_max_fds <= pack_open_fds && unuse_one_window(NULL, -1))
781 ; /* nothing */
782
f4e51683 783 p->pack_fd = git_open_noatime(p->pack_name);
9bc879c1 784 if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
072db278 785 return -1;
c7934306 786 pack_open_fds++;
9bc879c1
SP
787
788 /* If we created the struct before we had the pack we lack size. */
bf592c50 789 if (!p->pack_size) {
bf592c50 790 if (!S_ISREG(st.st_mode))
072db278 791 return error("packfile %s not a regular file", p->pack_name);
bf592c50 792 p->pack_size = st.st_size;
9bc879c1 793 } else if (p->pack_size != st.st_size)
072db278 794 return error("packfile %s size changed", p->pack_name);
9bc879c1 795
2c039da8
JH
796 /* We leave these file descriptors open with sliding mmap;
797 * there is no point keeping them open across exec(), though.
798 */
799 fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
800 if (fd_flag < 0)
072db278 801 return error("cannot determine file descriptor flags");
2c039da8
JH
802 fd_flag |= FD_CLOEXEC;
803 if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
072db278 804 return error("cannot set FD_CLOEXEC");
2c039da8 805
9bc879c1 806 /* Verify we recognize this pack file format. */
e6e2bd62 807 if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
072db278 808 return error("file %s is far too short to be a packfile", p->pack_name);
9bc879c1 809 if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
072db278 810 return error("file %s is not a GIT packfile", p->pack_name);
9bc879c1 811 if (!pack_version_ok(hdr.hdr_version))
6e1c2344
RJ
812 return error("packfile %s is version %"PRIu32" and not"
813 " supported (try upgrading GIT to a newer version)",
9bc879c1
SP
814 p->pack_name, ntohl(hdr.hdr_version));
815
816 /* Verify the pack matches its index. */
57059091 817 if (p->num_objects != ntohl(hdr.hdr_entries))
6e1c2344
RJ
818 return error("packfile %s claims to have %"PRIu32" objects"
819 " while index indicates %"PRIu32" objects",
57059091
NP
820 p->pack_name, ntohl(hdr.hdr_entries),
821 p->num_objects);
9bc879c1 822 if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
072db278 823 return error("end of packfile %s is unavailable", p->pack_name);
e6e2bd62 824 if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
072db278 825 return error("packfile %s signature is unavailable", p->pack_name);
42873078 826 idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40;
9bc879c1 827 if (hashcmp(sha1, idx_sha1))
072db278
SP
828 return error("packfile %s does not match index", p->pack_name);
829 return 0;
9bc879c1
SP
830}
831
3cf8b462
SP
832static int open_packed_git(struct packed_git *p)
833{
834 if (!open_packed_git_1(p))
835 return 0;
836 if (p->pack_fd != -1) {
837 close(p->pack_fd);
c7934306 838 pack_open_fds--;
3cf8b462
SP
839 p->pack_fd = -1;
840 }
841 return -1;
842}
843
c4001d92 844static int in_window(struct pack_window *win, off_t offset)
60bb8b14
SP
845{
846 /* We must promise at least 20 bytes (one hash) after the
847 * offset is available from this window, otherwise the offset
848 * is not actually in this window and a different window (which
849 * has that one hash excess) must be used. This is to support
850 * the object header and delta base parsing routines below.
851 */
852 off_t win_off = win->offset;
853 return win_off <= offset
854 && (offset + 20) <= (win_off + win->len);
855}
856
4b25d091 857unsigned char *use_pack(struct packed_git *p,
03e79c88 858 struct pack_window **w_cursor,
c4001d92 859 off_t offset,
ef49a7a0 860 unsigned long *left)
9bc879c1 861{
60bb8b14 862 struct pack_window *win = *w_cursor;
03e79c88 863
a9d98a14 864 /* Since packfiles end in a hash of their content and it's
60bb8b14
SP
865 * pointless to ask for an offset into the middle of that
866 * hash, and the in_window function above wouldn't match
867 * don't allow an offset too close to the end of the file.
868 */
d131b7af
SP
869 if (!p->pack_size && p->pack_fd == -1 && open_packed_git(p))
870 die("packfile %s cannot be accessed", p->pack_name);
60bb8b14
SP
871 if (offset > (p->pack_size - 20))
872 die("offset beyond end of packfile (truncated pack?)");
873
874 if (!win || !in_window(win, offset)) {
875 if (win)
876 win->inuse_cnt--;
877 for (win = p->windows; win; win = win->next) {
878 if (in_window(win, offset))
879 break;
880 }
881 if (!win) {
78a28df9 882 size_t window_align = packed_git_window_size / 2;
dc49cd76 883 off_t len;
d131b7af
SP
884
885 if (p->pack_fd == -1 && open_packed_git(p))
886 die("packfile %s cannot be accessed", p->pack_name);
887
60bb8b14 888 win = xcalloc(1, sizeof(*win));
78a28df9 889 win->offset = (offset / window_align) * window_align;
dc49cd76
SP
890 len = p->pack_size - win->offset;
891 if (len > packed_git_window_size)
892 len = packed_git_window_size;
893 win->len = (size_t)len;
60bb8b14 894 pack_mapped += win->len;
11daf39b 895 while (packed_git_limit < pack_mapped
d1efefa4 896 && unuse_one_window(p, p->pack_fd))
60bb8b14 897 ; /* nothing */
c4712e45 898 win->base = xmmap(NULL, win->len,
60bb8b14
SP
899 PROT_READ, MAP_PRIVATE,
900 p->pack_fd, win->offset);
901 if (win->base == MAP_FAILED)
73b4e4be
SP
902 die("packfile %s cannot be mapped: %s",
903 p->pack_name,
904 strerror(errno));
d131b7af
SP
905 if (!win->offset && win->len == p->pack_size
906 && !p->do_not_close) {
907 close(p->pack_fd);
908 pack_open_fds--;
909 p->pack_fd = -1;
910 }
a53128b6
SP
911 pack_mmap_calls++;
912 pack_open_windows++;
913 if (pack_mapped > peak_pack_mapped)
914 peak_pack_mapped = pack_mapped;
915 if (pack_open_windows > peak_pack_open_windows)
916 peak_pack_open_windows = pack_open_windows;
60bb8b14
SP
917 win->next = p->windows;
918 p->windows = win;
919 }
1f688557 920 }
03e79c88
SP
921 if (win != *w_cursor) {
922 win->last_used = pack_used_ctr++;
923 win->inuse_cnt++;
924 *w_cursor = win;
925 }
60bb8b14 926 offset -= win->offset;
03e79c88 927 if (left)
dc49cd76 928 *left = win->len - xsize_t(offset);
03e79c88 929 return win->base + offset;
1f688557
JH
930}
931
27d69a46
NP
932static struct packed_git *alloc_packed_git(int extra)
933{
934 struct packed_git *p = xmalloc(sizeof(*p) + extra);
935 memset(p, 0, sizeof(*p));
936 p->pack_fd = -1;
937 return p;
938}
939
e0500293
JN
940static void try_to_free_pack_memory(size_t size)
941{
942 release_pack_memory(size, -1);
943}
944
42873078 945struct packed_git *add_packed_git(const char *path, int path_len, int local)
1f688557 946{
e0500293 947 static int have_set_try_to_free_routine;
1f688557 948 struct stat st;
27d69a46 949 struct packed_git *p = alloc_packed_git(path_len + 2);
1f688557 950
e0500293
JN
951 if (!have_set_try_to_free_routine) {
952 have_set_try_to_free_routine = 1;
953 set_try_to_free_routine(try_to_free_pack_memory);
954 }
955
42873078
NP
956 /*
957 * Make sure a corresponding .pack file exists and that
958 * the index looks sane.
959 */
960 path_len -= strlen(".idx");
27d69a46
NP
961 if (path_len < 1) {
962 free(p);
1f688557 963 return NULL;
27d69a46 964 }
42873078 965 memcpy(p->pack_name, path, path_len);
8d25931d
BC
966
967 strcpy(p->pack_name + path_len, ".keep");
968 if (!access(p->pack_name, F_OK))
969 p->pack_keep = 1;
970
42873078 971 strcpy(p->pack_name + path_len, ".pack");
d079837e 972 if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
42873078 973 free(p);
1f688557
JH
974 return NULL;
975 }
42873078 976
1f688557
JH
977 /* ok, it looks sane as far as we can check without
978 * actually mapping the pack file.
979 */
1f688557 980 p->pack_size = st.st_size;
9d835df2 981 p->pack_local = local;
b867092f 982 p->mtime = st.st_mtime;
42873078
NP
983 if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1))
984 hashclr(p->sha1);
1f688557
JH
985 return p;
986}
987
7b64469a 988struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path)
c508df5e 989{
42873078 990 const char *path = sha1_pack_name(sha1);
27d69a46 991 struct packed_git *p = alloc_packed_git(strlen(path) + 1);
bf592c50 992
27d69a46
NP
993 strcpy(p->pack_name, path);
994 hashcpy(p->sha1, sha1);
42873078
NP
995 if (check_packed_git_idx(idx_path, p)) {
996 free(p);
bf592c50 997 return NULL;
42873078 998 }
bf592c50 999
bf592c50
DB
1000 return p;
1001}
1002
1003void install_packed_git(struct packed_git *pack)
1004{
c7934306
SP
1005 if (pack->pack_fd != -1)
1006 pack_open_fds++;
1007
bf592c50
DB
1008 pack->next = packed_git;
1009 packed_git = pack;
1010}
1011
543c5caa
NTND
1012void (*report_garbage)(const char *desc, const char *path);
1013
1014static void report_helper(const struct string_list *list,
1015 int seen_bits, int first, int last)
1016{
1017 const char *msg;
1018 switch (seen_bits) {
1019 case 0:
1020 msg = "no corresponding .idx nor .pack";
1021 break;
1022 case 1:
1023 msg = "no corresponding .idx";
1024 break;
1025 case 2:
1026 msg = "no corresponding .pack";
1027 break;
1028 default:
1029 return;
1030 }
1031 for (; first < last; first++)
1032 report_garbage(msg, list->items[first].string);
1033}
1034
1035static void report_pack_garbage(struct string_list *list)
1036{
1037 int i, baselen = -1, first = 0, seen_bits = 0;
1038
1039 if (!report_garbage)
1040 return;
1041
1042 sort_string_list(list);
1043
1044 for (i = 0; i < list->nr; i++) {
1045 const char *path = list->items[i].string;
1046 if (baselen != -1 &&
1047 strncmp(path, list->items[first].string, baselen)) {
1048 report_helper(list, seen_bits, first, i);
1049 baselen = -1;
1050 seen_bits = 0;
1051 }
1052 if (baselen == -1) {
1053 const char *dot = strrchr(path, '.');
1054 if (!dot) {
1055 report_garbage("garbage found", path);
1056 continue;
1057 }
1058 baselen = dot - path + 1;
1059 first = i;
1060 }
1061 if (!strcmp(path + baselen, "pack"))
1062 seen_bits |= 1;
1063 else if (!strcmp(path + baselen, "idx"))
1064 seen_bits |= 2;
1065 }
1066 report_helper(list, seen_bits, first, list->nr);
1067}
1068
9d835df2 1069static void prepare_packed_git_one(char *objdir, int local)
1f688557 1070{
9cb18f56
JM
1071 /* Ensure that this buffer is large enough so that we can
1072 append "/pack/" without clobbering the stack even if
1073 strlen(objdir) were PATH_MAX. */
1074 char path[PATH_MAX + 1 + 4 + 1 + 1];
1f688557
JH
1075 int len;
1076 DIR *dir;
1077 struct dirent *de;
543c5caa 1078 struct string_list garbage = STRING_LIST_INIT_DUP;
1f688557
JH
1079
1080 sprintf(path, "%s/pack", objdir);
1081 len = strlen(path);
1082 dir = opendir(path);
b5b16990 1083 if (!dir) {
26125f6b 1084 if (errno != ENOENT)
bd2afde8 1085 error("unable to open object pack directory: %s: %s",
26125f6b 1086 path, strerror(errno));
1f688557 1087 return;
b5b16990 1088 }
1f688557
JH
1089 path[len++] = '/';
1090 while ((de = readdir(dir)) != NULL) {
1091 int namelen = strlen(de->d_name);
1092 struct packed_git *p;
1093
543c5caa
NTND
1094 if (len + namelen + 1 > sizeof(path)) {
1095 if (report_garbage) {
1096 struct strbuf sb = STRBUF_INIT;
1097 strbuf_addf(&sb, "%.*s/%s", len - 1, path, de->d_name);
1098 report_garbage("path too long", sb.buf);
1099 strbuf_release(&sb);
1100 }
1101 continue;
1102 }
1103
1104 if (is_dot_or_dotdot(de->d_name))
9cb18f56
JM
1105 continue;
1106
1f688557 1107 strcpy(path + len, de->d_name);
d90906a9
NTND
1108
1109 if (has_extension(de->d_name, ".idx")) {
1110 /* Don't reopen a pack we already have. */
1111 for (p = packed_git; p; p = p->next) {
1112 if (!memcmp(path, p->pack_name, len + namelen - 4))
1113 break;
1114 }
1115 if (p == NULL &&
1116 /*
1117 * See if it really is a valid .idx file with
1118 * corresponding .pack file that we can map.
1119 */
1120 (p = add_packed_git(path, len + namelen, local)) != NULL)
1121 install_packed_git(p);
86f7780c 1122 }
543c5caa
NTND
1123
1124 if (!report_garbage)
1125 continue;
1126
1127 if (has_extension(de->d_name, ".idx") ||
1128 has_extension(de->d_name, ".pack") ||
1129 has_extension(de->d_name, ".keep"))
1130 string_list_append(&garbage, path);
1131 else
1132 report_garbage("garbage found", path);
1f688557 1133 }
5b35bcd5 1134 closedir(dir);
543c5caa
NTND
1135 report_pack_garbage(&garbage);
1136 string_list_clear(&garbage, 0);
1f688557
JH
1137}
1138
b867092f
JH
1139static int sort_pack(const void *a_, const void *b_)
1140{
1141 struct packed_git *a = *((struct packed_git **)a_);
1142 struct packed_git *b = *((struct packed_git **)b_);
1143 int st;
1144
1145 /*
1146 * Local packs tend to contain objects specific to our
1147 * variant of the project than remote ones. In addition,
1148 * remote ones could be on a network mounted filesystem.
1149 * Favor local ones for these reasons.
1150 */
1151 st = a->pack_local - b->pack_local;
1152 if (st)
1153 return -st;
1154
1155 /*
1156 * Younger packs tend to contain more recent objects,
1157 * and more recent objects tend to get accessed more
1158 * often.
1159 */
1160 if (a->mtime < b->mtime)
1161 return 1;
1162 else if (a->mtime == b->mtime)
1163 return 0;
1164 return -1;
1165}
1166
1167static void rearrange_packed_git(void)
1168{
1169 struct packed_git **ary, *p;
1170 int i, n;
1171
1172 for (n = 0, p = packed_git; p; p = p->next)
1173 n++;
1174 if (n < 2)
1175 return;
1176
1177 /* prepare an array of packed_git for easier sorting */
1178 ary = xcalloc(n, sizeof(struct packed_git *));
1179 for (n = 0, p = packed_git; p; p = p->next)
1180 ary[n++] = p;
1181
1182 qsort(ary, n, sizeof(struct packed_git *), sort_pack);
1183
1184 /* link them back again */
1185 for (i = 0; i < n - 1; i++)
1186 ary[i]->next = ary[i + 1];
1187 ary[n - 1]->next = NULL;
1188 packed_git = ary[0];
1189
1190 free(ary);
1191}
1192
637cdd9d 1193static int prepare_packed_git_run_once = 0;
9a217f2a 1194void prepare_packed_git(void)
1f688557 1195{
d5a63b99 1196 struct alternate_object_database *alt;
1f688557 1197
637cdd9d 1198 if (prepare_packed_git_run_once)
1f688557 1199 return;
9d835df2 1200 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 1201 prepare_alt_odb();
d5a63b99 1202 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 1203 alt->name[-1] = 0;
9d835df2 1204 prepare_packed_git_one(alt->base, 0);
1494e038 1205 alt->name[-1] = '/';
1f688557 1206 }
b867092f 1207 rearrange_packed_git();
637cdd9d
JK
1208 prepare_packed_git_run_once = 1;
1209}
1210
fc04c412 1211void reprepare_packed_git(void)
637cdd9d 1212{
4b480c67 1213 discard_revindex();
637cdd9d
JK
1214 prepare_packed_git_run_once = 0;
1215 prepare_packed_git();
1f688557
JH
1216}
1217
8eca0b47
NP
1218static void mark_bad_packed_object(struct packed_git *p,
1219 const unsigned char *sha1)
1220{
1221 unsigned i;
1222 for (i = 0; i < p->num_bad_objects; i++)
1223 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1224 return;
1225 p->bad_object_sha1 = xrealloc(p->bad_object_sha1, 20 * (p->num_bad_objects + 1));
1226 hashcpy(p->bad_object_sha1 + 20 * p->num_bad_objects, sha1);
1227 p->num_bad_objects++;
1228}
1229
b6c4cecc 1230static const struct packed_git *has_packed_and_bad(const unsigned char *sha1)
ac939109
NP
1231{
1232 struct packed_git *p;
1233 unsigned i;
1234
1235 for (p = packed_git; p; p = p->next)
1236 for (i = 0; i < p->num_bad_objects; i++)
1237 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
b6c4cecc
JH
1238 return p;
1239 return NULL;
ac939109
NP
1240}
1241
090ea126
NTND
1242/*
1243 * With an in-core object data in "map", rehash it to make sure the
1244 * object name actually matches "sha1" to detect object corruption.
1245 * With "map" == NULL, try reading the object named with "sha1" using
1246 * the streaming interface and rehash it to do the same.
1247 */
1248int check_sha1_signature(const unsigned char *sha1, void *map,
1249 unsigned long size, const char *type)
0fcfd160
LT
1250{
1251 unsigned char real_sha1[20];
090ea126
NTND
1252 enum object_type obj_type;
1253 struct git_istream *st;
1254 git_SHA_CTX c;
1255 char hdr[32];
1256 int hdrlen;
1257
1258 if (map) {
1259 hash_sha1_file(map, size, type, real_sha1);
1260 return hashcmp(sha1, real_sha1) ? -1 : 0;
1261 }
1262
1263 st = open_istream(sha1, &obj_type, &size, NULL);
1264 if (!st)
1265 return -1;
1266
1267 /* Generate the header */
1268 hdrlen = sprintf(hdr, "%s %lu", typename(obj_type), size) + 1;
1269
1270 /* Sha1.. */
1271 git_SHA1_Init(&c);
1272 git_SHA1_Update(&c, hdr, hdrlen);
1273 for (;;) {
1274 char buf[1024 * 16];
1275 ssize_t readlen = read_istream(st, buf, sizeof(buf));
1276
f54fac53
JK
1277 if (readlen < 0) {
1278 close_istream(st);
1279 return -1;
1280 }
090ea126
NTND
1281 if (!readlen)
1282 break;
1283 git_SHA1_Update(&c, buf, readlen);
1284 }
1285 git_SHA1_Final(real_sha1, &c);
1286 close_istream(st);
a89fccd2 1287 return hashcmp(sha1, real_sha1) ? -1 : 0;
0fcfd160
LT
1288}
1289
f4e51683 1290static int git_open_noatime(const char *name)
44d1c19e
LT
1291{
1292 static int sha1_file_open_flag = O_NOATIME;
44d1c19e 1293
f2e872aa
SP
1294 for (;;) {
1295 int fd = open(name, O_RDONLY | sha1_file_open_flag);
44d1c19e 1296 if (fd >= 0)
f2e872aa
SP
1297 return fd;
1298
f2e872aa
SP
1299 /* Might the failure be due to O_NOATIME? */
1300 if (errno != ENOENT && sha1_file_open_flag) {
44d1c19e 1301 sha1_file_open_flag = 0;
f2e872aa
SP
1302 continue;
1303 }
1304
1305 return -1;
44d1c19e 1306 }
44d1c19e
LT
1307}
1308
052fe5ea
JK
1309static int stat_sha1_file(const unsigned char *sha1, struct stat *st)
1310{
1311 char *name = sha1_file_name(sha1);
1312 struct alternate_object_database *alt;
1313
1314 if (!lstat(name, st))
1315 return 0;
1316
1317 prepare_alt_odb();
1318 errno = ENOENT;
1319 for (alt = alt_odb_list; alt; alt = alt->next) {
1320 name = alt->name;
1321 fill_sha1_path(name, sha1);
1322 if (!lstat(alt->base, st))
1323 return 0;
1324 }
1325
1326 return -1;
1327}
1328
44d1c19e
LT
1329static int open_sha1_file(const unsigned char *sha1)
1330{
1331 int fd;
1332 char *name = sha1_file_name(sha1);
1333 struct alternate_object_database *alt;
1334
f4e51683 1335 fd = git_open_noatime(name);
44d1c19e
LT
1336 if (fd >= 0)
1337 return fd;
1338
1339 prepare_alt_odb();
1340 errno = ENOENT;
1341 for (alt = alt_odb_list; alt; alt = alt->next) {
1342 name = alt->name;
1343 fill_sha1_path(name, sha1);
f4e51683 1344 fd = git_open_noatime(alt->base);
44d1c19e
LT
1345 if (fd >= 0)
1346 return fd;
1347 }
1348 return -1;
1349}
1350
f0270efd 1351void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
0fcfd160 1352{
0fcfd160 1353 void *map;
144bde78 1354 int fd;
ace1534d 1355
44d1c19e
LT
1356 fd = open_sha1_file(sha1);
1357 map = NULL;
1358 if (fd >= 0) {
1359 struct stat st;
0fcfd160 1360
44d1c19e
LT
1361 if (!fstat(fd, &st)) {
1362 *size = xsize_t(st.st_size);
33e42de0
MM
1363 if (!*size) {
1364 /* mmap() is forbidden on empty files */
1365 error("object file %s is empty", sha1_file_name(sha1));
1366 return NULL;
1367 }
44d1c19e 1368 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
144bde78 1369 }
44d1c19e 1370 close(fd);
0fcfd160 1371 }
0fcfd160
LT
1372 return map;
1373}
1374
cc5c54e7
JH
1375/*
1376 * There used to be a second loose object header format which
1377 * was meant to mimic the in-pack format, allowing for direct
1378 * copy of the object data. This format turned up not to be
1379 * really worth it and we no longer write loose objects in that
1380 * format.
1381 */
1382static int experimental_loose_object(unsigned char *map)
bb6b8e4f
JH
1383{
1384 unsigned int word;
1385
1386 /*
7f684a2a
RT
1387 * We must determine if the buffer contains the standard
1388 * zlib-deflated stream or the experimental format based
1389 * on the in-pack object format. Compare the header byte
1390 * for each format:
1391 *
1392 * RFC1950 zlib w/ deflate : 0www1000 : 0 <= www <= 7
1393 * Experimental pack-based : Stttssss : ttt = 1,2,3,4
1394 *
1395 * If bit 7 is clear and bits 0-3 equal 8, the buffer MUST be
1396 * in standard loose-object format, UNLESS it is a Git-pack
1397 * format object *exactly* 8 bytes in size when inflated.
1398 *
1399 * However, RFC1950 also specifies that the 1st 16-bit word
1400 * must be divisible by 31 - this checksum tells us our buffer
1401 * is in the standard format, giving a false positive only if
1402 * the 1st word of the Git-pack format object happens to be
1403 * divisible by 31, ie:
1404 * ((byte0 * 256) + byte1) % 31 = 0
1405 * => 0ttt10000www1000 % 31 = 0
1406 *
1407 * As it happens, this case can only arise for www=3 & ttt=1
1408 * - ie, a Commit object, which would have to be 8 bytes in
1409 * size. As no Commit can be that small, we find that the
1410 * combination of these two criteria (bitmask & checksum)
1411 * can always correctly determine the buffer format.
bb6b8e4f
JH
1412 */
1413 word = (map[0] << 8) + map[1];
7f684a2a 1414 if ((map[0] & 0x8F) == 0x08 && !(word % 31))
bb6b8e4f 1415 return 0;
cc5c54e7
JH
1416 else
1417 return 1;
bb6b8e4f
JH
1418}
1419
09ded04b
NP
1420unsigned long unpack_object_header_buffer(const unsigned char *buf,
1421 unsigned long len, enum object_type *type, unsigned long *sizep)
c4483576 1422{
ad1ed5ee 1423 unsigned shift;
48fb7deb 1424 unsigned long size, c;
ad1ed5ee
JH
1425 unsigned long used = 0;
1426
1427 c = buf[used++];
1428 *type = (c >> 4) & 7;
1429 size = c & 15;
1430 shift = 4;
1431 while (c & 0x80) {
f630cfda 1432 if (len <= used || bitsizeof(long) <= shift) {
09ded04b 1433 error("bad object header");
ea4f9685
JH
1434 size = used = 0;
1435 break;
09ded04b 1436 }
ad1ed5ee
JH
1437 c = buf[used++];
1438 size += (c & 0x7f) << shift;
1439 shift += 7;
1440 }
1441 *sizep = size;
1442 return used;
1443}
1444
eb4f4076 1445int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
ad1ed5ee
JH
1446{
1447 unsigned long size, used;
1448 static const char valid_loose_object_type[8] = {
1449 0, /* OBJ_EXT */
1450 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
1451 0, /* "delta" and others are invalid in a loose object */
93821bd9 1452 };
ad1ed5ee 1453 enum object_type type;
93821bd9 1454
c4483576
LT
1455 /* Get the data stream */
1456 memset(stream, 0, sizeof(*stream));
1457 stream->next_in = map;
1458 stream->avail_in = mapsize;
1459 stream->next_out = buffer;
93821bd9
LT
1460 stream->avail_out = bufsiz;
1461
cc5c54e7
JH
1462 if (experimental_loose_object(map)) {
1463 /*
1464 * The old experimental format we no longer produce;
1465 * we can still read it.
1466 */
1467 used = unpack_object_header_buffer(map, mapsize, &type, &size);
1468 if (!used || !valid_loose_object_type[type])
1469 return -1;
1470 map += used;
1471 mapsize -= used;
726f852b 1472
cc5c54e7
JH
1473 /* Set up the stream for the rest.. */
1474 stream->next_in = map;
1475 stream->avail_in = mapsize;
1476 git_inflate_init(stream);
93821bd9 1477
cc5c54e7
JH
1478 /* And generate the fake traditional header */
1479 stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
1480 typename(type), size);
1481 return 0;
1482 }
39c68542 1483 git_inflate_init(stream);
cc5c54e7 1484 return git_inflate(stream, 0);
c4483576
LT
1485}
1486
ef49a7a0 1487static void *unpack_sha1_rest(git_zstream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
5180cacc
LT
1488{
1489 int bytes = strlen(buffer) + 1;
3aee68aa 1490 unsigned char *buf = xmallocz(size);
93821bd9 1491 unsigned long n;
7efbff75 1492 int status = Z_OK;
5180cacc 1493
93821bd9
LT
1494 n = stream->total_out - bytes;
1495 if (n > size)
1496 n = size;
1497 memcpy(buf, (char *) buffer + bytes, n);
1498 bytes = n;
456cdf6e
LT
1499 if (bytes <= size) {
1500 /*
1501 * The above condition must be (bytes <= size), not
1502 * (bytes < size). In other words, even though we
ccf5ace0 1503 * expect no more output and set avail_out to zero,
456cdf6e
LT
1504 * the input zlib stream may have bytes that express
1505 * "this concludes the stream", and we *do* want to
1506 * eat that input.
1507 *
1508 * Otherwise we would not be able to test that we
1509 * consumed all the input to reach the expected size;
1510 * we also want to check that zlib tells us that all
1511 * went well with status == Z_STREAM_END at the end.
1512 */
5180cacc
LT
1513 stream->next_out = buf + bytes;
1514 stream->avail_out = size - bytes;
7efbff75 1515 while (status == Z_OK)
39c68542 1516 status = git_inflate(stream, Z_FINISH);
5180cacc 1517 }
456cdf6e 1518 if (status == Z_STREAM_END && !stream->avail_in) {
39c68542 1519 git_inflate_end(stream);
7efbff75
JH
1520 return buf;
1521 }
1522
1523 if (status < 0)
1524 error("corrupt loose object '%s'", sha1_to_hex(sha1));
1525 else if (stream->avail_in)
1526 error("garbage at end of loose object '%s'",
1527 sha1_to_hex(sha1));
1528 free(buf);
1529 return NULL;
5180cacc
LT
1530}
1531
1532/*
1533 * We used to just use "sscanf()", but that's actually way
1534 * too permissive for what we want to check. So do an anal
1535 * object header parse by hand.
1536 */
f0270efd 1537int parse_sha1_header(const char *hdr, unsigned long *sizep)
5180cacc 1538{
21666f1a 1539 char type[10];
5180cacc
LT
1540 int i;
1541 unsigned long size;
1542
1543 /*
a6080a0a 1544 * The type can be at most ten bytes (including the
5180cacc 1545 * terminating '\0' that we add), and is followed by
21666f1a 1546 * a space.
5180cacc 1547 */
21666f1a 1548 i = 0;
5180cacc
LT
1549 for (;;) {
1550 char c = *hdr++;
1551 if (c == ' ')
1552 break;
21666f1a
NP
1553 type[i++] = c;
1554 if (i >= sizeof(type))
5180cacc 1555 return -1;
5180cacc 1556 }
21666f1a 1557 type[i] = 0;
5180cacc
LT
1558
1559 /*
1560 * The length must follow immediately, and be in canonical
1561 * decimal format (ie "010" is not valid).
1562 */
1563 size = *hdr++ - '0';
1564 if (size > 9)
1565 return -1;
1566 if (size) {
1567 for (;;) {
1568 unsigned long c = *hdr - '0';
1569 if (c > 9)
1570 break;
1571 hdr++;
1572 size = size * 10 + c;
1573 }
1574 }
1575 *sizep = size;
1576
1577 /*
1578 * The length must be followed by a zero byte
1579 */
21666f1a 1580 return *hdr ? -1 : type_from_string(type);
5180cacc
LT
1581}
1582
7efbff75 1583static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
0fcfd160 1584{
5180cacc 1585 int ret;
ef49a7a0 1586 git_zstream stream;
5180cacc 1587 char hdr[8192];
0fcfd160 1588
5180cacc 1589 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
21666f1a 1590 if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
0fcfd160
LT
1591 return NULL;
1592
7efbff75 1593 return unpack_sha1_rest(&stream, hdr, *size, sha1);
0fcfd160
LT
1594}
1595
54dab52a
NP
1596unsigned long get_size_from_delta(struct packed_git *p,
1597 struct pack_window **w_curs,
1598 off_t curpos)
1599{
1600 const unsigned char *data;
1601 unsigned char delta_head[20], *in;
ef49a7a0 1602 git_zstream stream;
54dab52a
NP
1603 int st;
1604
1605 memset(&stream, 0, sizeof(stream));
1606 stream.next_out = delta_head;
1607 stream.avail_out = sizeof(delta_head);
1608
39c68542 1609 git_inflate_init(&stream);
54dab52a
NP
1610 do {
1611 in = use_pack(p, w_curs, curpos, &stream.avail_in);
1612 stream.next_in = in;
39c68542 1613 st = git_inflate(&stream, Z_FINISH);
54dab52a
NP
1614 curpos += stream.next_in - in;
1615 } while ((st == Z_OK || st == Z_BUF_ERROR) &&
1616 stream.total_out < sizeof(delta_head));
39c68542 1617 git_inflate_end(&stream);
3d77d877
NP
1618 if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) {
1619 error("delta data unpack-initial failed");
1620 return 0;
1621 }
54dab52a
NP
1622
1623 /* Examine the initial part of the delta to figure out
1624 * the result size.
1625 */
1626 data = delta_head;
1627
1628 /* ignore base size */
1629 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1630
1631 /* Read the result size */
1632 return get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1633}
1634
c4001d92 1635static off_t get_delta_base(struct packed_git *p,
03e79c88 1636 struct pack_window **w_curs,
c4001d92 1637 off_t *curpos,
21666f1a 1638 enum object_type type,
c4001d92 1639 off_t delta_obj_offset)
eb32d236 1640{
2b87c45b 1641 unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
c4001d92 1642 off_t base_offset;
eb32d236 1643
8d8a4ea5
SP
1644 /* use_pack() assured us we have [base_info, base_info + 20)
1645 * as a range that we can look at without walking off the
1646 * end of the mapped window. Its actually the hash size
1647 * that is assured. An OFS_DELTA longer than the hash size
1648 * is stupid, as then a REF_DELTA would be smaller to store.
1649 */
21666f1a 1650 if (type == OBJ_OFS_DELTA) {
eb32d236
NP
1651 unsigned used = 0;
1652 unsigned char c = base_info[used++];
1653 base_offset = c & 127;
1654 while (c & 128) {
1655 base_offset += 1;
8723f216 1656 if (!base_offset || MSB(base_offset, 7))
8eca0b47 1657 return 0; /* overflow */
eb32d236
NP
1658 c = base_info[used++];
1659 base_offset = (base_offset << 7) + (c & 127);
1660 }
1661 base_offset = delta_obj_offset - base_offset;
d8f32556 1662 if (base_offset <= 0 || base_offset >= delta_obj_offset)
8eca0b47 1663 return 0; /* out of bound */
2b87c45b 1664 *curpos += used;
21666f1a 1665 } else if (type == OBJ_REF_DELTA) {
eb32d236
NP
1666 /* The base entry _must_ be in the same pack */
1667 base_offset = find_pack_entry_one(base_info, p);
2b87c45b 1668 *curpos += 20;
eb32d236
NP
1669 } else
1670 die("I am totally screwed");
2b87c45b 1671 return base_offset;
eb32d236
NP
1672}
1673
f8c8abc5
JH
1674int unpack_object_header(struct packed_git *p,
1675 struct pack_window **w_curs,
1676 off_t *curpos,
1677 unsigned long *sizep)
a733cb60 1678{
03e79c88 1679 unsigned char *base;
ef49a7a0 1680 unsigned long left;
ad1ed5ee 1681 unsigned long used;
2b87c45b 1682 enum object_type type;
a733cb60 1683
8d8a4ea5 1684 /* use_pack() assures us we have [base, base + 20) available
0353a0c4 1685 * as a range that we can look at. (Its actually the hash
3dff5379 1686 * size that is assured.) With our object header encoding
8d8a4ea5
SP
1687 * the maximum deflated object size is 2^137, which is just
1688 * insane, so we know won't exceed what we have been given.
1689 */
2b87c45b 1690 base = use_pack(p, w_curs, *curpos, &left);
09ded04b
NP
1691 used = unpack_object_header_buffer(base, left, &type, sizep);
1692 if (!used) {
1693 type = OBJ_BAD;
1694 } else
1695 *curpos += used;
ad1ed5ee 1696
2b87c45b 1697 return type;
a733cb60
LT
1698}
1699
790d96c0
TR
1700static int retry_bad_packed_offset(struct packed_git *p, off_t obj_offset)
1701{
1702 int type;
1703 struct revindex_entry *revidx;
1704 const unsigned char *sha1;
1705 revidx = find_pack_revindex(p, obj_offset);
1706 if (!revidx)
1707 return OBJ_BAD;
1708 sha1 = nth_packed_object_sha1(p, revidx->nr);
1709 mark_bad_packed_object(p, sha1);
1710 type = sha1_object_info(sha1, NULL);
1711 if (type <= OBJ_NONE)
1712 return OBJ_BAD;
1713 return type;
1714}
1715
790d96c0
TR
1716#define POI_STACK_PREALLOC 64
1717
90191d37
JK
1718static enum object_type packed_to_object_type(struct packed_git *p,
1719 off_t obj_offset,
1720 enum object_type type,
1721 struct pack_window **w_curs,
1722 off_t curpos)
1f688557 1723{
790d96c0
TR
1724 off_t small_poi_stack[POI_STACK_PREALLOC];
1725 off_t *poi_stack = small_poi_stack;
1726 int poi_stack_nr = 0, poi_stack_alloc = POI_STACK_PREALLOC;
5db47c2b 1727
790d96c0
TR
1728 while (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
1729 off_t base_offset;
90191d37 1730 unsigned long size;
790d96c0
TR
1731 /* Push the object we're going to leave behind */
1732 if (poi_stack_nr >= poi_stack_alloc && poi_stack == small_poi_stack) {
1733 poi_stack_alloc = alloc_nr(poi_stack_nr);
1734 poi_stack = xmalloc(sizeof(off_t)*poi_stack_alloc);
1735 memcpy(poi_stack, small_poi_stack, sizeof(off_t)*poi_stack_nr);
1736 } else {
1737 ALLOC_GROW(poi_stack, poi_stack_nr+1, poi_stack_alloc);
1738 }
1739 poi_stack[poi_stack_nr++] = obj_offset;
1740 /* If parsing the base offset fails, just unwind */
90191d37 1741 base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
790d96c0
TR
1742 if (!base_offset)
1743 goto unwind;
1744 curpos = obj_offset = base_offset;
90191d37 1745 type = unpack_object_header(p, w_curs, &curpos, &size);
790d96c0
TR
1746 if (type <= OBJ_NONE) {
1747 /* If getting the base itself fails, we first
1748 * retry the base, otherwise unwind */
1749 type = retry_bad_packed_offset(p, base_offset);
1750 if (type > OBJ_NONE)
1751 goto out;
1752 goto unwind;
1753 }
1754 }
1755
21666f1a 1756 switch (type) {
790d96c0 1757 case OBJ_BAD:
a733cb60 1758 case OBJ_COMMIT:
a733cb60 1759 case OBJ_TREE:
a733cb60 1760 case OBJ_BLOB:
a733cb60 1761 case OBJ_TAG:
a69d0943 1762 break;
1f688557 1763 default:
3d77d877
NP
1764 error("unknown object type %i at offset %"PRIuMAX" in %s",
1765 type, (uintmax_t)obj_offset, p->pack_name);
1766 type = OBJ_BAD;
1f688557 1767 }
790d96c0
TR
1768
1769out:
1770 if (poi_stack != small_poi_stack)
1771 free(poi_stack);
21666f1a 1772 return type;
790d96c0
TR
1773
1774unwind:
1775 while (poi_stack_nr) {
1776 obj_offset = poi_stack[--poi_stack_nr];
1777 type = retry_bad_packed_offset(p, obj_offset);
1778 if (type > OBJ_NONE)
1779 goto out;
1780 }
1781 type = OBJ_BAD;
1782 goto out;
1f688557
JH
1783}
1784
90191d37 1785static int packed_object_info(struct packed_git *p, off_t obj_offset,
23c339c0 1786 struct object_info *oi)
90191d37
JK
1787{
1788 struct pack_window *w_curs = NULL;
1789 unsigned long size;
1790 off_t curpos = obj_offset;
1791 enum object_type type;
1792
412916ee
JK
1793 /*
1794 * We always get the representation type, but only convert it to
1795 * a "real" type later if the caller is interested.
1796 */
90191d37
JK
1797 type = unpack_object_header(p, &w_curs, &curpos, &size);
1798
23c339c0 1799 if (oi->sizep) {
90191d37
JK
1800 if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
1801 off_t tmp_pos = curpos;
1802 off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos,
1803 type, obj_offset);
1804 if (!base_offset) {
1805 type = OBJ_BAD;
1806 goto out;
1807 }
23c339c0
JK
1808 *oi->sizep = get_size_from_delta(p, &w_curs, tmp_pos);
1809 if (*oi->sizep == 0) {
90191d37
JK
1810 type = OBJ_BAD;
1811 goto out;
1812 }
1813 } else {
23c339c0 1814 *oi->sizep = size;
90191d37
JK
1815 }
1816 }
1817
23c339c0 1818 if (oi->disk_sizep) {
90191d37 1819 struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
23c339c0 1820 *oi->disk_sizep = revidx[1].offset - obj_offset;
90191d37
JK
1821 }
1822
23c339c0
JK
1823 if (oi->typep) {
1824 *oi->typep = packed_to_object_type(p, obj_offset, type, &w_curs, curpos);
1825 if (*oi->typep < 0) {
412916ee
JK
1826 type = OBJ_BAD;
1827 goto out;
1828 }
1829 }
90191d37
JK
1830
1831out:
1832 unuse_pack(&w_curs);
1833 return type;
1834}
1835
eb950c19 1836static void *unpack_compressed_entry(struct packed_git *p,
03e79c88 1837 struct pack_window **w_curs,
c4001d92 1838 off_t curpos,
eb950c19 1839 unsigned long size)
de530aaa
SP
1840{
1841 int st;
ef49a7a0 1842 git_zstream stream;
079afb18 1843 unsigned char *buffer, *in;
de530aaa 1844
4ab07e4d 1845 buffer = xmallocz(size);
de530aaa 1846 memset(&stream, 0, sizeof(stream));
de530aaa 1847 stream.next_out = buffer;
39eea7bd 1848 stream.avail_out = size + 1;
de530aaa 1849
39c68542 1850 git_inflate_init(&stream);
079afb18 1851 do {
2b87c45b 1852 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18 1853 stream.next_in = in;
39c68542 1854 st = git_inflate(&stream, Z_FINISH);
39eea7bd
JH
1855 if (!stream.avail_out)
1856 break; /* the payload is larger than it should be */
2b87c45b 1857 curpos += stream.next_in - in;
079afb18 1858 } while (st == Z_OK || st == Z_BUF_ERROR);
39c68542 1859 git_inflate_end(&stream);
de530aaa
SP
1860 if ((st != Z_STREAM_END) || stream.total_out != size) {
1861 free(buffer);
1862 return NULL;
1863 }
1864
1865 return buffer;
1866}
1867
e5e01619
LT
1868#define MAX_DELTA_CACHE (256)
1869
18bdec11 1870static size_t delta_base_cached;
5e08ecbf
NP
1871
1872static struct delta_base_cache_lru_list {
1873 struct delta_base_cache_lru_list *prev;
1874 struct delta_base_cache_lru_list *next;
1875} delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru };
1876
e5e01619 1877static struct delta_base_cache_entry {
5e08ecbf
NP
1878 struct delta_base_cache_lru_list lru;
1879 void *data;
e5e01619
LT
1880 struct packed_git *p;
1881 off_t base_offset;
1882 unsigned long size;
e5e01619
LT
1883 enum object_type type;
1884} delta_base_cache[MAX_DELTA_CACHE];
1885
1886static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
1887{
1888 unsigned long hash;
1889
1890 hash = (unsigned long)p + (unsigned long)base_offset;
1891 hash += (hash >> 8) + (hash >> 16);
3358004a 1892 return hash % MAX_DELTA_CACHE;
e5e01619
LT
1893}
1894
84dd81c1
TR
1895static struct delta_base_cache_entry *
1896get_delta_base_cache_entry(struct packed_git *p, off_t base_offset)
5266d369
JH
1897{
1898 unsigned long hash = pack_entry_hash(p, base_offset);
84dd81c1
TR
1899 return delta_base_cache + hash;
1900}
1901
1902static int eq_delta_base_cache_entry(struct delta_base_cache_entry *ent,
1903 struct packed_git *p, off_t base_offset)
1904{
5266d369
JH
1905 return (ent->data && ent->p == p && ent->base_offset == base_offset);
1906}
1907
84dd81c1
TR
1908static int in_delta_base_cache(struct packed_git *p, off_t base_offset)
1909{
1910 struct delta_base_cache_entry *ent;
1911 ent = get_delta_base_cache_entry(p, base_offset);
1912 return eq_delta_base_cache_entry(ent, p, base_offset);
1913}
1914
1915static void clear_delta_base_cache_entry(struct delta_base_cache_entry *ent)
1916{
1917 ent->data = NULL;
1918 ent->lru.next->prev = ent->lru.prev;
1919 ent->lru.prev->next = ent->lru.next;
1920 delta_base_cached -= ent->size;
1921}
1922
62f255ad 1923static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
a0cba108 1924 unsigned long *base_size, enum object_type *type, int keep_cache)
62f255ad 1925{
84dd81c1 1926 struct delta_base_cache_entry *ent;
e5e01619 1927 void *ret;
e5e01619 1928
84dd81c1
TR
1929 ent = get_delta_base_cache_entry(p, base_offset);
1930
1931 if (!eq_delta_base_cache_entry(ent, p, base_offset))
749bc58c 1932 return unpack_entry(p, base_offset, type, base_size);
e5e01619 1933
84dd81c1
TR
1934 ret = ent->data;
1935
1936 if (!keep_cache)
1937 clear_delta_base_cache_entry(ent);
1938 else
182af834 1939 ret = xmemdupz(ent->data, ent->size);
e5e01619
LT
1940 *type = ent->type;
1941 *base_size = ent->size;
1942 return ret;
62f255ad
LT
1943}
1944
18bdec11
SP
1945static inline void release_delta_base_cache(struct delta_base_cache_entry *ent)
1946{
1947 if (ent->data) {
1948 free(ent->data);
1949 ent->data = NULL;
5e08ecbf
NP
1950 ent->lru.next->prev = ent->lru.prev;
1951 ent->lru.prev->next = ent->lru.next;
18bdec11
SP
1952 delta_base_cached -= ent->size;
1953 }
1954}
1955
3d20c636
SP
1956void clear_delta_base_cache(void)
1957{
1958 unsigned long p;
1959 for (p = 0; p < MAX_DELTA_CACHE; p++)
1960 release_delta_base_cache(&delta_base_cache[p]);
1961}
1962
62f255ad
LT
1963static void add_delta_base_cache(struct packed_git *p, off_t base_offset,
1964 void *base, unsigned long base_size, enum object_type type)
1965{
5e08ecbf 1966 unsigned long hash = pack_entry_hash(p, base_offset);
e5e01619 1967 struct delta_base_cache_entry *ent = delta_base_cache + hash;
5e08ecbf 1968 struct delta_base_cache_lru_list *lru;
e5e01619 1969
18bdec11
SP
1970 release_delta_base_cache(ent);
1971 delta_base_cached += base_size;
5e08ecbf
NP
1972
1973 for (lru = delta_base_cache_lru.next;
1974 delta_base_cached > delta_base_cache_limit
1975 && lru != &delta_base_cache_lru;
1976 lru = lru->next) {
1977 struct delta_base_cache_entry *f = (void *)lru;
18bdec11
SP
1978 if (f->type == OBJ_BLOB)
1979 release_delta_base_cache(f);
1980 }
5e08ecbf
NP
1981 for (lru = delta_base_cache_lru.next;
1982 delta_base_cached > delta_base_cache_limit
1983 && lru != &delta_base_cache_lru;
1984 lru = lru->next) {
1985 struct delta_base_cache_entry *f = (void *)lru;
1986 release_delta_base_cache(f);
1987 }
18bdec11 1988
e5e01619
LT
1989 ent->p = p;
1990 ent->base_offset = base_offset;
1991 ent->type = type;
1992 ent->data = base;
1993 ent->size = base_size;
5e08ecbf
NP
1994 ent->lru.next = &delta_base_cache_lru;
1995 ent->lru.prev = delta_base_cache_lru.prev;
1996 delta_base_cache_lru.prev->next = &ent->lru;
1997 delta_base_cache_lru.prev = &ent->lru;
62f255ad
LT
1998}
1999
c2c5b270
CC
2000static void *read_object(const unsigned char *sha1, enum object_type *type,
2001 unsigned long *size);
2002
5f44324d
JH
2003static void write_pack_access_log(struct packed_git *p, off_t obj_offset)
2004{
2005 static FILE *log_file;
2006
b12ca963
NTND
2007 if (!log_pack_access)
2008 log_pack_access = getenv("GIT_TRACE_PACK_ACCESS");
2009 if (!log_pack_access)
2010 log_pack_access = no_log_pack_access;
2011 if (log_pack_access == no_log_pack_access)
2012 return;
2013
5f44324d
JH
2014 if (!log_file) {
2015 log_file = fopen(log_pack_access, "w");
2016 if (!log_file) {
2017 error("cannot open pack access log '%s' for writing: %s",
2018 log_pack_access, strerror(errno));
b12ca963 2019 log_pack_access = no_log_pack_access;
5f44324d
JH
2020 return;
2021 }
2022 }
2023 fprintf(log_file, "%s %"PRIuMAX"\n",
2024 p->pack_name, (uintmax_t)obj_offset);
2025 fflush(log_file);
2026}
2027
0e8189e2
NP
2028int do_check_packed_object_crc;
2029
abe601bb
TR
2030#define UNPACK_ENTRY_STACK_PREALLOC 64
2031struct unpack_entry_stack_ent {
2032 off_t obj_offset;
2033 off_t curpos;
2034 unsigned long size;
2035};
2036
c4001d92 2037void *unpack_entry(struct packed_git *p, off_t obj_offset,
abe601bb 2038 enum object_type *final_type, unsigned long *final_size)
1f688557 2039{
03e79c88 2040 struct pack_window *w_curs = NULL;
c4001d92 2041 off_t curpos = obj_offset;
abe601bb
TR
2042 void *data = NULL;
2043 unsigned long size;
2044 enum object_type type;
2045 struct unpack_entry_stack_ent small_delta_stack[UNPACK_ENTRY_STACK_PREALLOC];
2046 struct unpack_entry_stack_ent *delta_stack = small_delta_stack;
2047 int delta_stack_nr = 0, delta_stack_alloc = UNPACK_ENTRY_STACK_PREALLOC;
2048 int base_from_cache = 0;
1f688557 2049
b12ca963 2050 if (log_pack_access != no_log_pack_access)
5f44324d
JH
2051 write_pack_access_log(p, obj_offset);
2052
abe601bb
TR
2053 /* PHASE 1: drill down to the innermost base object */
2054 for (;;) {
2055 off_t base_offset;
2056 int i;
2057 struct delta_base_cache_entry *ent;
2058
2059 if (do_check_packed_object_crc && p->index_version > 1) {
2060 struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
2061 unsigned long len = revidx[1].offset - obj_offset;
2062 if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) {
2063 const unsigned char *sha1 =
2064 nth_packed_object_sha1(p, revidx->nr);
2065 error("bad packed object CRC for %s",
2066 sha1_to_hex(sha1));
2067 mark_bad_packed_object(p, sha1);
2068 unuse_pack(&w_curs);
2069 return NULL;
2070 }
2071 }
2072
2073 ent = get_delta_base_cache_entry(p, curpos);
2074 if (eq_delta_base_cache_entry(ent, p, curpos)) {
2075 type = ent->type;
2076 data = ent->data;
2077 size = ent->size;
2078 clear_delta_base_cache_entry(ent);
2079 base_from_cache = 1;
2080 break;
0e8189e2 2081 }
abe601bb
TR
2082
2083 type = unpack_object_header(p, &w_curs, &curpos, &size);
2084 if (type != OBJ_OFS_DELTA && type != OBJ_REF_DELTA)
2085 break;
2086
2087 base_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
2088 if (!base_offset) {
2089 error("failed to validate delta base reference "
2090 "at offset %"PRIuMAX" from %s",
2091 (uintmax_t)curpos, p->pack_name);
2092 /* bail to phase 2, in hopes of recovery */
2093 data = NULL;
2094 break;
2095 }
2096
2097 /* push object, proceed to base */
2098 if (delta_stack_nr >= delta_stack_alloc
2099 && delta_stack == small_delta_stack) {
2100 delta_stack_alloc = alloc_nr(delta_stack_nr);
2101 delta_stack = xmalloc(sizeof(*delta_stack)*delta_stack_alloc);
2102 memcpy(delta_stack, small_delta_stack,
2103 sizeof(*delta_stack)*delta_stack_nr);
2104 } else {
2105 ALLOC_GROW(delta_stack, delta_stack_nr+1, delta_stack_alloc);
2106 }
2107 i = delta_stack_nr++;
2108 delta_stack[i].obj_offset = obj_offset;
2109 delta_stack[i].curpos = curpos;
2110 delta_stack[i].size = size;
2111
2112 curpos = obj_offset = base_offset;
0e8189e2
NP
2113 }
2114
abe601bb
TR
2115 /* PHASE 2: handle the base */
2116 switch (type) {
eb32d236
NP
2117 case OBJ_OFS_DELTA:
2118 case OBJ_REF_DELTA:
abe601bb
TR
2119 if (data)
2120 die("BUG in unpack_entry: left loop at a valid delta");
4d703a1a 2121 break;
a733cb60 2122 case OBJ_COMMIT:
a733cb60 2123 case OBJ_TREE:
a733cb60 2124 case OBJ_BLOB:
a733cb60 2125 case OBJ_TAG:
abe601bb
TR
2126 if (!base_from_cache)
2127 data = unpack_compressed_entry(p, &w_curs, curpos, size);
4d703a1a 2128 break;
1f688557 2129 default:
8eca0b47
NP
2130 data = NULL;
2131 error("unknown object type %i at offset %"PRIuMAX" in %s",
abe601bb
TR
2132 type, (uintmax_t)obj_offset, p->pack_name);
2133 }
2134
2135 /* PHASE 3: apply deltas in order */
2136
2137 /* invariants:
2138 * 'data' holds the base data, or NULL if there was corruption
2139 */
2140 while (delta_stack_nr) {
2141 void *delta_data;
2142 void *base = data;
2143 unsigned long delta_size, base_size = size;
2144 int i;
2145
2146 data = NULL;
2147
2148 if (base)
2149 add_delta_base_cache(p, obj_offset, base, base_size, type);
2150
2151 if (!base) {
2152 /*
2153 * We're probably in deep shit, but let's try to fetch
2154 * the required base anyway from another pack or loose.
2155 * This is costly but should happen only in the presence
2156 * of a corrupted pack, and is better than failing outright.
2157 */
2158 struct revindex_entry *revidx;
2159 const unsigned char *base_sha1;
2160 revidx = find_pack_revindex(p, obj_offset);
2161 if (revidx) {
2162 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
2163 error("failed to read delta base object %s"
2164 " at offset %"PRIuMAX" from %s",
2165 sha1_to_hex(base_sha1), (uintmax_t)obj_offset,
2166 p->pack_name);
2167 mark_bad_packed_object(p, base_sha1);
2168 base = read_object(base_sha1, &type, &base_size);
2169 }
2170 }
2171
2172 i = --delta_stack_nr;
2173 obj_offset = delta_stack[i].obj_offset;
2174 curpos = delta_stack[i].curpos;
2175 delta_size = delta_stack[i].size;
2176
2177 if (!base)
2178 continue;
2179
2180 delta_data = unpack_compressed_entry(p, &w_curs, curpos, delta_size);
2181
2182 if (!delta_data) {
2183 error("failed to unpack compressed delta "
2184 "at offset %"PRIuMAX" from %s",
2185 (uintmax_t)curpos, p->pack_name);
abe601bb
TR
2186 data = NULL;
2187 continue;
2188 }
2189
2190 data = patch_delta(base, base_size,
2191 delta_data, delta_size,
2192 &size);
1ee886c1
JK
2193
2194 /*
2195 * We could not apply the delta; warn the user, but keep going.
2196 * Our failure will be noticed either in the next iteration of
2197 * the loop, or if this is the final delta, in the caller when
2198 * we return NULL. Those code paths will take care of making
2199 * a more explicit warning and retrying with another copy of
2200 * the object.
2201 */
abe601bb 2202 if (!data)
1ee886c1 2203 error("failed to apply delta");
abe601bb 2204
4b8f772c 2205 free(delta_data);
1f688557 2206 }
abe601bb
TR
2207
2208 *final_type = type;
2209 *final_size = size;
2210
03e79c88 2211 unuse_pack(&w_curs);
21666f1a 2212 return data;
1f688557
JH
2213}
2214
d079837e 2215const unsigned char *nth_packed_object_sha1(struct packed_git *p,
d72308e0 2216 uint32_t n)
9a217f2a 2217{
42873078 2218 const unsigned char *index = p->index_data;
d079837e
SP
2219 if (!index) {
2220 if (open_pack_index(p))
2221 return NULL;
2222 index = p->index_data;
2223 }
57059091 2224 if (n >= p->num_objects)
d72308e0 2225 return NULL;
74e34e1f
NP
2226 index += 4 * 256;
2227 if (p->index_version == 1) {
2228 return index + 24 * n + 4;
2229 } else {
2230 index += 8;
2231 return index + 20 * n;
2232 }
2233}
2234
99093238 2235off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
74e34e1f
NP
2236{
2237 const unsigned char *index = p->index_data;
2238 index += 4 * 256;
2239 if (p->index_version == 1) {
2240 return ntohl(*((uint32_t *)(index + 24 * n)));
2241 } else {
2242 uint32_t off;
2243 index += 8 + p->num_objects * (20 + 4);
2244 off = ntohl(*((uint32_t *)(index + 4 * n)));
2245 if (!(off & 0x80000000))
2246 return off;
2247 index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
2248 return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
2249 ntohl(*((uint32_t *)(index + 4)));
2250 }
9a217f2a
JH
2251}
2252
c4001d92 2253off_t find_pack_entry_one(const unsigned char *sha1,
43057304 2254 struct packed_git *p)
1f688557 2255{
42873078 2256 const uint32_t *level1_ofs = p->index_data;
42873078 2257 const unsigned char *index = p->index_data;
628522ec
JH
2258 unsigned hi, lo, stride;
2259 static int use_lookup = -1;
2260 static int debug_lookup = -1;
2261
2262 if (debug_lookup < 0)
2263 debug_lookup = !!getenv("GIT_DEBUG_LOOKUP");
42873078 2264
d079837e
SP
2265 if (!index) {
2266 if (open_pack_index(p))
2267 return 0;
2268 level1_ofs = p->index_data;
2269 index = p->index_data;
2270 }
74e34e1f
NP
2271 if (p->index_version > 1) {
2272 level1_ofs += 2;
2273 index += 8;
2274 }
42873078 2275 index += 4 * 256;
74e34e1f
NP
2276 hi = ntohl(level1_ofs[*sha1]);
2277 lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
628522ec
JH
2278 if (p->index_version > 1) {
2279 stride = 20;
2280 } else {
2281 stride = 24;
2282 index += 4;
2283 }
2284
2285 if (debug_lookup)
6e1c2344 2286 printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n",
628522ec
JH
2287 sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects);
2288
2289 if (use_lookup < 0)
2290 use_lookup = !!getenv("GIT_USE_LOOKUP");
2291 if (use_lookup) {
2292 int pos = sha1_entry_pos(index, stride, 0,
2293 lo, hi, p->num_objects, sha1);
2294 if (pos < 0)
2295 return 0;
2296 return nth_packed_object_offset(p, pos);
2297 }
1f688557
JH
2298
2299 do {
74e34e1f 2300 unsigned mi = (lo + hi) / 2;
628522ec
JH
2301 int cmp = hashcmp(index + mi * stride, sha1);
2302
2303 if (debug_lookup)
2304 printf("lo %u hi %u rg %u mi %u\n",
2305 lo, hi, hi - lo, mi);
43057304 2306 if (!cmp)
74e34e1f 2307 return nth_packed_object_offset(p, mi);
1f688557
JH
2308 if (cmp > 0)
2309 hi = mi;
2310 else
2311 lo = mi+1;
2312 } while (lo < hi);
2313 return 0;
2314}
2315
4c080182 2316int is_pack_valid(struct packed_git *p)
d131b7af
SP
2317{
2318 /* An already open pack is known to be valid. */
2319 if (p->pack_fd != -1)
2320 return 1;
2321
2322 /* If the pack has one window completely covering the
2323 * file size, the pack is known to be valid even if
2324 * the descriptor is not currently open.
2325 */
2326 if (p->windows) {
2327 struct pack_window *w = p->windows;
2328
2329 if (!w->offset && w->len == p->pack_size)
2330 return 1;
2331 }
2332
2333 /* Force the pack to open to prove its valid. */
2334 return !open_packed_git(p);
2335}
2336
95099731
NTND
2337static int fill_pack_entry(const unsigned char *sha1,
2338 struct pack_entry *e,
2339 struct packed_git *p)
2340{
2341 off_t offset;
2342
2343 if (p->num_bad_objects) {
2344 unsigned i;
2345 for (i = 0; i < p->num_bad_objects; i++)
2346 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
2347 return 0;
2348 }
2349
2350 offset = find_pack_entry_one(sha1, p);
2351 if (!offset)
2352 return 0;
2353
2354 /*
2355 * We are about to tell the caller where they can locate the
2356 * requested object. We better make sure the packfile is
2357 * still here and can be accessed before supplying that
2358 * answer, as it may have been deleted since the index was
2359 * loaded!
2360 */
2361 if (!is_pack_valid(p)) {
2362 warning("packfile %s cannot be accessed", p->pack_name);
2363 return 0;
2364 }
2365 e->offset = offset;
2366 e->p = p;
2367 hashcpy(e->sha1, sha1);
2368 return 1;
2369}
2370
4d6acb70 2371static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1f688557
JH
2372{
2373 struct packed_git *p;
43057304 2374
1f688557 2375 prepare_packed_git();
f7c22cc6
NP
2376 if (!packed_git)
2377 return 0;
1f688557 2378
c01f51cc
NTND
2379 if (last_found_pack && fill_pack_entry(sha1, e, last_found_pack))
2380 return 1;
8eca0b47 2381
c01f51cc
NTND
2382 for (p = packed_git; p; p = p->next) {
2383 if (p == last_found_pack || !fill_pack_entry(sha1, e, p))
2384 continue;
f7c22cc6 2385
c01f51cc
NTND
2386 last_found_pack = p;
2387 return 1;
2388 }
1f688557
JH
2389 return 0;
2390}
2391
a6080a0a 2392struct packed_git *find_sha1_pack(const unsigned char *sha1,
bf592c50
DB
2393 struct packed_git *packs)
2394{
2395 struct packed_git *p;
bf592c50
DB
2396
2397 for (p = packs; p; p = p->next) {
43057304 2398 if (find_pack_entry_one(sha1, p))
bf592c50
DB
2399 return p;
2400 }
2401 return NULL;
21666f1a 2402
bf592c50
DB
2403}
2404
052fe5ea 2405static int sha1_loose_object_info(const unsigned char *sha1,
23c339c0 2406 struct object_info *oi)
65c2e0c3 2407{
36e4d74a 2408 int status;
65c2e0c3
JH
2409 unsigned long mapsize, size;
2410 void *map;
ef49a7a0 2411 git_zstream stream;
d65a16f6 2412 char hdr[32];
65c2e0c3 2413
052fe5ea
JK
2414 /*
2415 * If we don't care about type or size, then we don't
2416 * need to look inside the object at all.
2417 */
23c339c0
JK
2418 if (!oi->typep && !oi->sizep) {
2419 if (oi->disk_sizep) {
052fe5ea
JK
2420 struct stat st;
2421 if (stat_sha1_file(sha1, &st) < 0)
2422 return -1;
23c339c0 2423 *oi->disk_sizep = st.st_size;
052fe5ea
JK
2424 }
2425 return 0;
2426 }
2427
bb6b8e4f 2428 map = map_sha1_file(sha1, &mapsize);
f0df4ed5 2429 if (!map)
dbea72a8 2430 return -1;
23c339c0
JK
2431 if (oi->disk_sizep)
2432 *oi->disk_sizep = mapsize;
36e4d74a
JH
2433 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
2434 status = error("unable to unpack %s header",
2435 sha1_to_hex(sha1));
21666f1a 2436 else if ((status = parse_sha1_header(hdr, &size)) < 0)
36e4d74a 2437 status = error("unable to parse %s header", sha1_to_hex(sha1));
23c339c0
JK
2438 else if (oi->sizep)
2439 *oi->sizep = size;
39c68542 2440 git_inflate_end(&stream);
65c2e0c3 2441 munmap(map, mapsize);
23c339c0
JK
2442 if (oi->typep)
2443 *oi->typep = status;
052fe5ea 2444 return 0;
65c2e0c3
JH
2445}
2446
9a490590 2447int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
f0df4ed5 2448{
c4d9986f 2449 struct cached_object *co;
f0df4ed5 2450 struct pack_entry e;
5b086407 2451 int rtype;
f0df4ed5 2452
c4d9986f
NTND
2453 co = find_cached_object(sha1);
2454 if (co) {
5b086407
JK
2455 if (oi->typep)
2456 *(oi->typep) = co->type;
9a490590
JH
2457 if (oi->sizep)
2458 *(oi->sizep) = co->size;
161f00e7
JK
2459 if (oi->disk_sizep)
2460 *(oi->disk_sizep) = 0;
9a490590 2461 oi->whence = OI_CACHED;
5b086407 2462 return 0;
c4d9986f
NTND
2463 }
2464
cd673c1f 2465 if (!find_pack_entry(sha1, &e)) {
ddd63e64 2466 /* Most likely it's a loose object. */
23c339c0 2467 if (!sha1_loose_object_info(sha1, oi)) {
9a490590 2468 oi->whence = OI_LOOSE;
5b086407 2469 return 0;
9a490590 2470 }
ddd63e64
SG
2471
2472 /* Not a loose object; someone else may have just packed it. */
f0df4ed5 2473 reprepare_packed_git();
cd673c1f 2474 if (!find_pack_entry(sha1, &e))
052fe5ea 2475 return -1;
f0df4ed5 2476 }
3d77d877 2477
23c339c0 2478 rtype = packed_object_info(e.p, e.offset, oi);
412916ee 2479 if (rtype < 0) {
3d77d877 2480 mark_bad_packed_object(e.p, sha1);
412916ee 2481 return sha1_object_info_extended(sha1, oi);
5266d369
JH
2482 } else if (in_delta_base_cache(e.p, e.offset)) {
2483 oi->whence = OI_DBCACHED;
9a490590
JH
2484 } else {
2485 oi->whence = OI_PACKED;
2486 oi->u.packed.offset = e.offset;
2487 oi->u.packed.pack = e.p;
2488 oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
2489 rtype == OBJ_OFS_DELTA);
3d77d877
NP
2490 }
2491
5b086407 2492 return 0;
f0df4ed5
JS
2493}
2494
3fc0dca9 2495/* returns enum object_type or negative */
9a490590
JH
2496int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
2497{
5b086407 2498 enum object_type type;
d099b717 2499 struct object_info oi = {NULL};
9a490590 2500
5b086407 2501 oi.typep = &type;
9a490590 2502 oi.sizep = sizep;
5b086407
JK
2503 if (sha1_object_info_extended(sha1, &oi) < 0)
2504 return -1;
2505 return type;
9a490590
JH
2506}
2507
21666f1a
NP
2508static void *read_packed_sha1(const unsigned char *sha1,
2509 enum object_type *type, unsigned long *size)
1f688557
JH
2510{
2511 struct pack_entry e;
8eca0b47 2512 void *data;
1f688557 2513
cd673c1f 2514 if (!find_pack_entry(sha1, &e))
1f688557 2515 return NULL;
8eca0b47
NP
2516 data = cache_or_unpack_entry(e.p, e.offset, size, type, 1);
2517 if (!data) {
2518 /*
2519 * We're probably in deep shit, but let's try to fetch
2520 * the required object anyway from another pack or loose.
2521 * This should happen only in the presence of a corrupted
2522 * pack, and is better than failing outright.
2523 */
2524 error("failed to read object %s at offset %"PRIuMAX" from %s",
2525 sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name);
2526 mark_bad_packed_object(e.p, sha1);
ac939109 2527 data = read_object(sha1, type, size);
8eca0b47
NP
2528 }
2529 return data;
1f688557
JH
2530}
2531
21666f1a
NP
2532int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
2533 unsigned char *sha1)
d66b37bb
JH
2534{
2535 struct cached_object *co;
2536
21666f1a 2537 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
2538 if (has_sha1_file(sha1) || find_cached_object(sha1))
2539 return 0;
2540 if (cached_object_alloc <= cached_object_nr) {
2541 cached_object_alloc = alloc_nr(cached_object_alloc);
2542 cached_objects = xrealloc(cached_objects,
2543 sizeof(*cached_objects) *
2544 cached_object_alloc);
2545 }
2546 co = &cached_objects[cached_object_nr++];
2547 co->size = len;
21666f1a 2548 co->type = type;
efa13f7b
JH
2549 co->buf = xmalloc(len);
2550 memcpy(co->buf, buf, len);
d66b37bb
JH
2551 hashcpy(co->sha1, sha1);
2552 return 0;
2553}
2554
c2c5b270
CC
2555static void *read_object(const unsigned char *sha1, enum object_type *type,
2556 unsigned long *size)
0fcfd160
LT
2557{
2558 unsigned long mapsize;
2559 void *map, *buf;
d66b37bb
JH
2560 struct cached_object *co;
2561
2562 co = find_cached_object(sha1);
2563 if (co) {
21666f1a 2564 *type = co->type;
d66b37bb 2565 *size = co->size;
182af834 2566 return xmemdupz(co->buf, co->size);
d66b37bb 2567 }
0fcfd160 2568
8276c007
PE
2569 buf = read_packed_sha1(sha1, type, size);
2570 if (buf)
2571 return buf;
bb6b8e4f 2572 map = map_sha1_file(sha1, &mapsize);
0fcfd160 2573 if (map) {
7efbff75 2574 buf = unpack_sha1_file(map, mapsize, type, size, sha1);
0fcfd160
LT
2575 munmap(map, mapsize);
2576 return buf;
2577 }
637cdd9d 2578 reprepare_packed_git();
8276c007 2579 return read_packed_sha1(sha1, type, size);
0fcfd160
LT
2580}
2581
b6c4cecc
JH
2582/*
2583 * This function dies on corrupt objects; the callers who want to
2584 * deal with them should arrange to call read_object() and give error
2585 * messages themselves.
2586 */
5bf29b95
JH
2587void *read_sha1_file_extended(const unsigned char *sha1,
2588 enum object_type *type,
2589 unsigned long *size,
2590 unsigned flag)
ac939109 2591{
3ba7a065 2592 void *data;
e8b15e61 2593 char *path;
b6c4cecc 2594 const struct packed_git *p;
5bf29b95
JH
2595 const unsigned char *repl = (flag & READ_SHA1_FILE_REPLACE)
2596 ? lookup_replace_object(sha1) : sha1;
b6c4cecc 2597
3ba7a065
JH
2598 errno = 0;
2599 data = read_object(repl, type, size);
4bbf5a26 2600 if (data)
b6c4cecc 2601 return data;
68095570 2602
25f3af3f 2603 if (errno && errno != ENOENT)
3ba7a065
JH
2604 die_errno("failed to read object %s", sha1_to_hex(sha1));
2605
68095570 2606 /* die if we replaced an object with one that does not exist */
b6c4cecc 2607 if (repl != sha1)
68095570
CC
2608 die("replacement %s not found for %s",
2609 sha1_to_hex(repl), sha1_to_hex(sha1));
2610
b6c4cecc
JH
2611 if (has_loose_object(repl)) {
2612 path = sha1_file_name(sha1);
2613 die("loose object %s (stored in %s) is corrupt",
2614 sha1_to_hex(repl), path);
e8b15e61 2615 }
68095570 2616
b6c4cecc
JH
2617 if ((p = has_packed_and_bad(repl)) != NULL)
2618 die("packed object %s (stored in %s) is corrupt",
2619 sha1_to_hex(repl), p->pack_name);
f5552aee 2620
b6c4cecc 2621 return NULL;
ac939109
NP
2622}
2623
40469ee9 2624void *read_object_with_reference(const unsigned char *sha1,
21666f1a 2625 const char *required_type_name,
40469ee9
JH
2626 unsigned long *size,
2627 unsigned char *actual_sha1_return)
f4913f91 2628{
21666f1a 2629 enum object_type type, required_type;
f4913f91
JH
2630 void *buffer;
2631 unsigned long isize;
40469ee9 2632 unsigned char actual_sha1[20];
f4913f91 2633
21666f1a 2634 required_type = type_from_string(required_type_name);
e702496e 2635 hashcpy(actual_sha1, sha1);
40469ee9
JH
2636 while (1) {
2637 int ref_length = -1;
2638 const char *ref_type = NULL;
f4913f91 2639
21666f1a 2640 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
2641 if (!buffer)
2642 return NULL;
21666f1a 2643 if (type == required_type) {
40469ee9
JH
2644 *size = isize;
2645 if (actual_sha1_return)
e702496e 2646 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
2647 return buffer;
2648 }
2649 /* Handle references */
21666f1a 2650 else if (type == OBJ_COMMIT)
40469ee9 2651 ref_type = "tree ";
21666f1a 2652 else if (type == OBJ_TAG)
40469ee9
JH
2653 ref_type = "object ";
2654 else {
2655 free(buffer);
2656 return NULL;
2657 }
2658 ref_length = strlen(ref_type);
f4913f91 2659
50974ec9
MK
2660 if (ref_length + 40 > isize ||
2661 memcmp(buffer, ref_type, ref_length) ||
1d7f171c 2662 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
2663 free(buffer);
2664 return NULL;
2665 }
1cf58e72 2666 free(buffer);
40469ee9
JH
2667 /* Now we have the ID of the referred-to object in
2668 * actual_sha1. Check again. */
f4913f91 2669 }
f4913f91
JH
2670}
2671
ce9fbf16 2672static void write_sha1_file_prepare(const void *buf, unsigned long len,
972a9155 2673 const char *type, unsigned char *sha1,
d65a16f6 2674 char *hdr, int *hdrlen)
d410c0f5 2675{
9126f009 2676 git_SHA_CTX c;
d410c0f5
JH
2677
2678 /* Generate the header */
d65a16f6 2679 *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
d410c0f5
JH
2680
2681 /* Sha1.. */
9126f009
NP
2682 git_SHA1_Init(&c);
2683 git_SHA1_Update(&c, hdr, *hdrlen);
2684 git_SHA1_Update(&c, buf, len);
2685 git_SHA1_Final(sha1, &c);
d410c0f5
JH
2686}
2687
230f1322 2688/*
5a688fe4
JH
2689 * Move the just written object into its final resting place.
2690 * NEEDSWORK: this should be renamed to finalize_temp_file() as
2691 * "moving" is only a part of what it does, when no patch between
2692 * master to pu changes the call sites of this function.
230f1322 2693 */
839837b9 2694int move_temp_to_file(const char *tmpfile, const char *filename)
230f1322 2695{
e32c0a9c 2696 int ret = 0;
5a688fe4 2697
348df166 2698 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
be66a6c4
JS
2699 goto try_rename;
2700 else if (link(tmpfile, filename))
e32c0a9c 2701 ret = errno;
7ebb6fca
LT
2702
2703 /*
2704 * Coda hack - coda doesn't like cross-directory links,
2705 * so we fall back to a rename, which will mean that it
2706 * won't be able to check collisions, but that's not a
2707 * big deal.
2708 *
2709 * The same holds for FAT formatted media.
2710 *
3be1f18e 2711 * When this succeeds, we just return. We have nothing
7ebb6fca
LT
2712 * left to unlink.
2713 */
2714 if (ret && ret != EEXIST) {
be66a6c4 2715 try_rename:
7ebb6fca 2716 if (!rename(tmpfile, filename))
3be1f18e 2717 goto out;
9e48b389 2718 ret = errno;
230f1322 2719 }
691f1a28 2720 unlink_or_warn(tmpfile);
230f1322
LT
2721 if (ret) {
2722 if (ret != EEXIST) {
82247e9b 2723 return error("unable to write sha1 filename %s: %s", filename, strerror(ret));
230f1322
LT
2724 }
2725 /* FIXME!!! Collision check here ? */
2726 }
2727
3be1f18e 2728out:
5256b006 2729 if (adjust_shared_perm(filename))
5a688fe4 2730 return error("unable to set permission to '%s'", filename);
230f1322
LT
2731 return 0;
2732}
2733
4d548150
LT
2734static int write_buffer(int fd, const void *buf, size_t len)
2735{
d34cf19b 2736 if (write_in_full(fd, buf, len) < 0)
93822c22 2737 return error("file write error (%s)", strerror(errno));
4d548150
LT
2738 return 0;
2739}
2740
ce9fbf16 2741int hash_sha1_file(const void *buf, unsigned long len, const char *type,
abdc3fc8
RS
2742 unsigned char *sha1)
2743{
d65a16f6 2744 char hdr[32];
abdc3fc8
RS
2745 int hdrlen;
2746 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2747 return 0;
2748}
2749
e9039dd3
LT
2750/* Finalize a file on disk, and close it. */
2751static void close_sha1_file(int fd)
2752{
aafe9fba
LT
2753 if (fsync_object_files)
2754 fsync_or_die(fd, "sha1 file");
e9039dd3 2755 if (close(fd) != 0)
d824cbba 2756 die_errno("error when closing sha1 file");
e9039dd3
LT
2757}
2758
5723fe7e
LT
2759/* Size of directory component, including the ending '/' */
2760static inline int directory_size(const char *filename)
2761{
2762 const char *s = strrchr(filename, '/');
2763 if (!s)
2764 return 0;
2765 return s - filename + 1;
2766}
2767
2768/*
2769 * This creates a temporary file in the same directory as the final
2770 * 'filename'
2771 *
2772 * We want to avoid cross-directory filename renames, because those
2773 * can have problems on various filesystems (FAT, NFS, Coda).
2774 */
2775static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename)
2776{
2777 int fd, dirlen = directory_size(filename);
2778
2779 if (dirlen + 20 > bufsiz) {
2780 errno = ENAMETOOLONG;
2781 return -1;
2782 }
2783 memcpy(buffer, filename, dirlen);
2784 strcpy(buffer + dirlen, "tmp_obj_XXXXXX");
5256b006 2785 fd = git_mkstemp_mode(buffer, 0444);
cbacbf4e 2786 if (fd < 0 && dirlen && errno == ENOENT) {
5723fe7e 2787 /* Make sure the directory exists */
6ff6af62 2788 memcpy(buffer, filename, dirlen);
5723fe7e 2789 buffer[dirlen-1] = 0;
3bfaf018 2790 if (mkdir(buffer, 0777) || adjust_shared_perm(buffer))
5723fe7e
LT
2791 return -1;
2792
2793 /* Try again */
2794 strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX");
5256b006 2795 fd = git_mkstemp_mode(buffer, 0444);
5723fe7e
LT
2796 }
2797 return fd;
2798}
2799
bbac7311 2800static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
c00e657d 2801 const void *buf, unsigned long len, time_t mtime)
0fcfd160 2802{
915308b1 2803 int fd, ret;
9892beba 2804 unsigned char compressed[4096];
ef49a7a0 2805 git_zstream stream;
748af44c
NP
2806 git_SHA_CTX c;
2807 unsigned char parano_sha1[20];
706bc531 2808 char *filename;
ab1900a3 2809 static char tmp_file[PATH_MAX];
a44c9a5e 2810
972a9155 2811 filename = sha1_file_name(sha1);
ab1900a3 2812 fd = create_tmpfile(tmp_file, sizeof(tmp_file), filename);
aac17941 2813 if (fd < 0) {
35243577 2814 if (errno == EACCES)
82247e9b 2815 return error("insufficient permission for adding an object to repository database %s", get_object_directory());
916d081b 2816 else
5eaeda70 2817 return error("unable to create temporary file: %s", strerror(errno));
aac17941
LT
2818 }
2819
0fcfd160
LT
2820 /* Set it up */
2821 memset(&stream, 0, sizeof(stream));
55bb5c91 2822 git_deflate_init(&stream, zlib_compression_level);
0fcfd160 2823 stream.next_out = compressed;
9892beba 2824 stream.avail_out = sizeof(compressed);
748af44c 2825 git_SHA1_Init(&c);
a44c9a5e
LT
2826
2827 /* First header.. */
d65a16f6 2828 stream.next_in = (unsigned char *)hdr;
a44c9a5e 2829 stream.avail_in = hdrlen;
55bb5c91
JH
2830 while (git_deflate(&stream, 0) == Z_OK)
2831 ; /* nothing */
748af44c 2832 git_SHA1_Update(&c, hdr, hdrlen);
a44c9a5e
LT
2833
2834 /* Then the data itself.. */
c00e657d 2835 stream.next_in = (void *)buf;
a44c9a5e 2836 stream.avail_in = len;
9892beba 2837 do {
748af44c 2838 unsigned char *in0 = stream.next_in;
55bb5c91 2839 ret = git_deflate(&stream, Z_FINISH);
748af44c 2840 git_SHA1_Update(&c, in0, stream.next_in - in0);
9892beba
NP
2841 if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
2842 die("unable to write sha1 file");
2843 stream.next_out = compressed;
2844 stream.avail_out = sizeof(compressed);
2845 } while (ret == Z_OK);
2846
ac54c277
LT
2847 if (ret != Z_STREAM_END)
2848 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
55bb5c91 2849 ret = git_deflate_end_gently(&stream);
ac54c277
LT
2850 if (ret != Z_OK)
2851 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
748af44c
NP
2852 git_SHA1_Final(parano_sha1, &c);
2853 if (hashcmp(sha1, parano_sha1) != 0)
2854 die("confused by unstable object source data for %s", sha1_to_hex(sha1));
ac54c277 2855
e9039dd3 2856 close_sha1_file(fd);
0fcfd160 2857
bbac7311
NP
2858 if (mtime) {
2859 struct utimbuf utb;
2860 utb.actime = mtime;
2861 utb.modtime = mtime;
ab1900a3 2862 if (utime(tmp_file, &utb) < 0)
bbac7311 2863 warning("failed utime() on %s: %s",
ab1900a3 2864 tmp_file, strerror(errno));
bbac7311
NP
2865 }
2866
ab1900a3 2867 return move_temp_to_file(tmp_file, filename);
0fcfd160 2868}
8237b185 2869
c00e657d 2870int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
bbac7311
NP
2871{
2872 unsigned char sha1[20];
2873 char hdr[32];
2874 int hdrlen;
2875
2876 /* Normally if we have it in the pack then we do not bother writing
2877 * it out into .git/objects/??/?{38} file.
2878 */
2879 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2880 if (returnsha1)
2881 hashcpy(returnsha1, sha1);
2882 if (has_sha1_file(sha1))
2883 return 0;
2884 return write_loose_object(sha1, hdr, hdrlen, buf, len, 0);
2885}
2886
2887int force_object_loose(const unsigned char *sha1, time_t mtime)
2888{
bbac7311
NP
2889 void *buf;
2890 unsigned long len;
2891 enum object_type type;
2892 char hdr[32];
2893 int hdrlen;
1fb23e65 2894 int ret;
bbac7311 2895
c529d75a 2896 if (has_loose_object(sha1))
bbac7311
NP
2897 return 0;
2898 buf = read_packed_sha1(sha1, &type, &len);
2899 if (!buf)
2900 return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
2901 hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
1fb23e65
BS
2902 ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
2903 free(buf);
2904
2905 return ret;
bbac7311
NP
2906}
2907
bf592c50
DB
2908int has_pack_index(const unsigned char *sha1)
2909{
2910 struct stat st;
2911 if (stat(sha1_pack_index_name(sha1), &st))
2912 return 0;
2913 return 1;
bf592c50
DB
2914}
2915
cd673c1f
JH
2916int has_sha1_pack(const unsigned char *sha1)
2917{
2918 struct pack_entry e;
2919 return find_pack_entry(sha1, &e);
2920}
2921
8237b185
DB
2922int has_sha1_file(const unsigned char *sha1)
2923{
1f688557
JH
2924 struct pack_entry e;
2925
cd673c1f 2926 if (find_pack_entry(sha1, &e))
1f688557 2927 return 1;
45e8a748
JK
2928 if (has_loose_object(sha1))
2929 return 1;
2930 reprepare_packed_git();
2931 return find_pack_entry(sha1, &e);
8237b185 2932}
74400e71 2933
c879daa2
NTND
2934static void check_tree(const void *buf, size_t size)
2935{
2936 struct tree_desc desc;
2937 struct name_entry entry;
2938
2939 init_tree_desc(&desc, buf, size);
2940 while (tree_entry(&desc, &entry))
2941 /* do nothing
2942 * tree_entry() will die() on malformed entries */
2943 ;
2944}
2945
2946static void check_commit(const void *buf, size_t size)
2947{
2948 struct commit c;
2949 memset(&c, 0, sizeof(c));
2950 if (parse_commit_buffer(&c, buf, size))
2951 die("corrupt commit");
2952}
2953
2954static void check_tag(const void *buf, size_t size)
2955{
2956 struct tag t;
2957 memset(&t, 0, sizeof(t));
2958 if (parse_tag_buffer(&t, buf, size))
2959 die("corrupt tag");
2960}
2961
43df4f86 2962static int index_mem(unsigned char *sha1, void *buf, size_t size,
c4ce46fc
JH
2963 enum object_type type,
2964 const char *path, unsigned flags)
e7332f96 2965{
6c510bee 2966 int ret, re_allocated = 0;
c4ce46fc 2967 int write_object = flags & HASH_WRITE_OBJECT;
74400e71 2968
7672db20 2969 if (!type)
edaec3fb 2970 type = OBJ_BLOB;
6c510bee
LT
2971
2972 /*
2973 * Convert blobs to git internal format
2974 */
43df4f86 2975 if ((type == OBJ_BLOB) && path) {
f285a2d7 2976 struct strbuf nbuf = STRBUF_INIT;
21e5ad50 2977 if (convert_to_git(path, buf, size, &nbuf,
5e12e78e 2978 write_object ? safe_crlf : SAFE_CRLF_FALSE)) {
b315c5c0 2979 buf = strbuf_detach(&nbuf, &size);
6c510bee
LT
2980 re_allocated = 1;
2981 }
2982 }
c4ce46fc 2983 if (flags & HASH_FORMAT_CHECK) {
c879daa2
NTND
2984 if (type == OBJ_TREE)
2985 check_tree(buf, size);
2986 if (type == OBJ_COMMIT)
2987 check_commit(buf, size);
2988 if (type == OBJ_TAG)
2989 check_tag(buf, size);
2990 }
6c510bee 2991
7672db20 2992 if (write_object)
edaec3fb 2993 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 2994 else
edaec3fb 2995 ret = hash_sha1_file(buf, size, typename(type), sha1);
43df4f86 2996 if (re_allocated)
6c510bee 2997 free(buf);
43df4f86
DP
2998 return ret;
2999}
3000
7b41e1e1
JH
3001static int index_pipe(unsigned char *sha1, int fd, enum object_type type,
3002 const char *path, unsigned flags)
3003{
3004 struct strbuf sbuf = STRBUF_INIT;
3005 int ret;
3006
3007 if (strbuf_read(&sbuf, fd, 4096) >= 0)
3008 ret = index_mem(sha1, sbuf.buf, sbuf.len, type, path, flags);
3009 else
3010 ret = -1;
3011 strbuf_release(&sbuf);
3012 return ret;
3013}
3014
ea68b0ce
DP
3015#define SMALL_FILE_SIZE (32*1024)
3016
7b41e1e1
JH
3017static int index_core(unsigned char *sha1, int fd, size_t size,
3018 enum object_type type, const char *path,
3019 unsigned flags)
43df4f86
DP
3020{
3021 int ret;
43df4f86 3022
7b41e1e1 3023 if (!size) {
c4ce46fc 3024 ret = index_mem(sha1, NULL, size, type, path, flags);
ea68b0ce
DP
3025 } else if (size <= SMALL_FILE_SIZE) {
3026 char *buf = xmalloc(size);
3027 if (size == read_in_full(fd, buf, size))
c4ce46fc 3028 ret = index_mem(sha1, buf, size, type, path, flags);
ea68b0ce
DP
3029 else
3030 ret = error("short read %s", strerror(errno));
3031 free(buf);
08bda208 3032 } else {
43df4f86 3033 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
c4ce46fc 3034 ret = index_mem(sha1, buf, size, type, path, flags);
aac17941 3035 munmap(buf, size);
08bda208 3036 }
7b41e1e1
JH
3037 return ret;
3038}
3039
4dd1fbc7 3040/*
568508e7
JH
3041 * This creates one packfile per large blob unless bulk-checkin
3042 * machinery is "plugged".
4dd1fbc7
JH
3043 *
3044 * This also bypasses the usual "convert-to-git" dance, and that is on
3045 * purpose. We could write a streaming version of the converting
3046 * functions and insert that before feeding the data to fast-import
4f22b101
JK
3047 * (or equivalent in-core API described above). However, that is
3048 * somewhat complicated, as we do not know the size of the filter
3049 * result, which we need to know beforehand when writing a git object.
3050 * Since the primary motivation for trying to stream from the working
3051 * tree file and to avoid mmaping it in core is to deal with large
3052 * binary blobs, they generally do not want to get any conversion, and
3053 * callers should avoid this code path when filters are requested.
4dd1fbc7
JH
3054 */
3055static int index_stream(unsigned char *sha1, int fd, size_t size,
3056 enum object_type type, const char *path,
3057 unsigned flags)
3058{
568508e7 3059 return index_bulk_checkin(sha1, fd, size, type, path, flags);
4dd1fbc7
JH
3060}
3061
7b41e1e1
JH
3062int index_fd(unsigned char *sha1, int fd, struct stat *st,
3063 enum object_type type, const char *path, unsigned flags)
3064{
3065 int ret;
3066 size_t size = xsize_t(st->st_size);
3067
3068 if (!S_ISREG(st->st_mode))
3069 ret = index_pipe(sha1, fd, type, path, flags);
4f22b101
JK
3070 else if (size <= big_file_threshold || type != OBJ_BLOB ||
3071 (path && would_convert_to_git(path, NULL, 0, 0)))
7b41e1e1 3072 ret = index_core(sha1, fd, size, type, path, flags);
4dd1fbc7
JH
3073 else
3074 ret = index_stream(sha1, fd, size, type, path, flags);
43df4f86 3075 close(fd);
aac17941 3076 return ret;
74400e71 3077}
ec1fcc16 3078
c4ce46fc 3079int index_path(unsigned char *sha1, const char *path, struct stat *st, unsigned flags)
ec1fcc16
JH
3080{
3081 int fd;
b760d3aa 3082 struct strbuf sb = STRBUF_INIT;
ec1fcc16
JH
3083
3084 switch (st->st_mode & S_IFMT) {
3085 case S_IFREG:
3086 fd = open(path, O_RDONLY);
3087 if (fd < 0)
3088 return error("open(\"%s\"): %s", path,
3089 strerror(errno));
c4ce46fc 3090 if (index_fd(sha1, fd, st, OBJ_BLOB, path, flags) < 0)
ec1fcc16
JH
3091 return error("%s: failed to insert into database",
3092 path);
3093 break;
3094 case S_IFLNK:
b760d3aa 3095 if (strbuf_readlink(&sb, path, st->st_size)) {
ec1fcc16 3096 char *errstr = strerror(errno);
ec1fcc16
JH
3097 return error("readlink(\"%s\"): %s", path,
3098 errstr);
3099 }
c4ce46fc 3100 if (!(flags & HASH_WRITE_OBJECT))
b760d3aa
LT
3101 hash_sha1_file(sb.buf, sb.len, blob_type, sha1);
3102 else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1))
ec1fcc16
JH
3103 return error("%s: failed to insert into database",
3104 path);
b760d3aa 3105 strbuf_release(&sb);
ec1fcc16 3106 break;
f35a6d3b
LT
3107 case S_IFDIR:
3108 return resolve_gitlink_ref(path, "HEAD", sha1);
ec1fcc16
JH
3109 default:
3110 return error("%s: unsupported file type", path);
3111 }
3112 return 0;
3113}
a69e5429
JH
3114
3115int read_pack_header(int fd, struct pack_header *header)
3116{
c697ad14
HO
3117 if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header))
3118 /* "eof before pack header was fully read" */
3119 return PH_ERROR_EOF;
3120
a69e5429
JH
3121 if (header->hdr_signature != htonl(PACK_SIGNATURE))
3122 /* "protocol error (pack signature mismatch detected)" */
3123 return PH_ERROR_PACK_SIGNATURE;
3124 if (!pack_version_ok(header->hdr_version))
3125 /* "protocol error (pack version unsupported)" */
3126 return PH_ERROR_PROTOCOL;
3127 return 0;
3128}
40d52ff7
JK
3129
3130void assert_sha1_type(const unsigned char *sha1, enum object_type expect)
3131{
3132 enum object_type type = sha1_object_info(sha1, NULL);
3133 if (type < 0)
3134 die("%s is not a valid object", sha1_to_hex(sha1));
3135 if (type != expect)
3136 die("%s is not a valid '%s' object", sha1_to_hex(sha1),
3137 typename(expect));
3138}