replace_object: add mechanism to replace objects found in "refs/replace/"
[git/git.git] / sha1_file.c
CommitLineData
0fcfd160
LT
1/*
2 * GIT - The information manager from hell
3 *
4 * Copyright (C) Linus Torvalds, 2005
5 *
6 * This handles basic git sha1 object files - packing, unpacking,
7 * creation etc.
8 */
0fcfd160 9#include "cache.h"
1f688557 10#include "delta.h"
a733cb60 11#include "pack.h"
8e440259
PE
12#include "blob.h"
13#include "commit.h"
14#include "tag.h"
15#include "tree.h"
f35a6d3b 16#include "refs.h"
70f5d5d3 17#include "pack-revindex.h"
628522ec 18#include "sha1-lookup.h"
0fcfd160 19
144bde78
LT
20#ifndef O_NOATIME
21#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
22#define O_NOATIME 01000000
23#else
24#define O_NOATIME 0
25#endif
26#endif
27
e05db0fd
PR
28#ifdef NO_C99_FORMAT
29#define SZ_FMT "lu"
9e42d6a1 30static unsigned long sz_fmt(size_t s) { return (unsigned long)s; }
e05db0fd
PR
31#else
32#define SZ_FMT "zu"
9e42d6a1 33static size_t sz_fmt(size_t s) { return s; }
e05db0fd
PR
34#endif
35
96f1e58f 36const unsigned char null_sha1[20];
88cd621d 37
192a6be2 38const signed char hexval_table[256] = {
e49521b5
JH
39 -1, -1, -1, -1, -1, -1, -1, -1, /* 00-07 */
40 -1, -1, -1, -1, -1, -1, -1, -1, /* 08-0f */
41 -1, -1, -1, -1, -1, -1, -1, -1, /* 10-17 */
42 -1, -1, -1, -1, -1, -1, -1, -1, /* 18-1f */
43 -1, -1, -1, -1, -1, -1, -1, -1, /* 20-27 */
44 -1, -1, -1, -1, -1, -1, -1, -1, /* 28-2f */
45 0, 1, 2, 3, 4, 5, 6, 7, /* 30-37 */
46 8, 9, -1, -1, -1, -1, -1, -1, /* 38-3f */
47 -1, 10, 11, 12, 13, 14, 15, -1, /* 40-47 */
48 -1, -1, -1, -1, -1, -1, -1, -1, /* 48-4f */
49 -1, -1, -1, -1, -1, -1, -1, -1, /* 50-57 */
50 -1, -1, -1, -1, -1, -1, -1, -1, /* 58-5f */
51 -1, 10, 11, 12, 13, 14, 15, -1, /* 60-67 */
52 -1, -1, -1, -1, -1, -1, -1, -1, /* 68-67 */
53 -1, -1, -1, -1, -1, -1, -1, -1, /* 70-77 */
54 -1, -1, -1, -1, -1, -1, -1, -1, /* 78-7f */
55 -1, -1, -1, -1, -1, -1, -1, -1, /* 80-87 */
56 -1, -1, -1, -1, -1, -1, -1, -1, /* 88-8f */
57 -1, -1, -1, -1, -1, -1, -1, -1, /* 90-97 */
58 -1, -1, -1, -1, -1, -1, -1, -1, /* 98-9f */
59 -1, -1, -1, -1, -1, -1, -1, -1, /* a0-a7 */
60 -1, -1, -1, -1, -1, -1, -1, -1, /* a8-af */
61 -1, -1, -1, -1, -1, -1, -1, -1, /* b0-b7 */
62 -1, -1, -1, -1, -1, -1, -1, -1, /* b8-bf */
63 -1, -1, -1, -1, -1, -1, -1, -1, /* c0-c7 */
64 -1, -1, -1, -1, -1, -1, -1, -1, /* c8-cf */
65 -1, -1, -1, -1, -1, -1, -1, -1, /* d0-d7 */
66 -1, -1, -1, -1, -1, -1, -1, -1, /* d8-df */
67 -1, -1, -1, -1, -1, -1, -1, -1, /* e0-e7 */
68 -1, -1, -1, -1, -1, -1, -1, -1, /* e8-ef */
69 -1, -1, -1, -1, -1, -1, -1, -1, /* f0-f7 */
70 -1, -1, -1, -1, -1, -1, -1, -1, /* f8-ff */
71};
0fcfd160
LT
72
73int get_sha1_hex(const char *hex, unsigned char *sha1)
74{
75 int i;
76 for (i = 0; i < 20; i++) {
77 unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
78 if (val & ~0xff)
79 return -1;
80 *sha1++ = val;
81 hex += 2;
82 }
83 return 0;
84}
85
8385abfd
JS
86static inline int offset_1st_component(const char *path)
87{
88 if (has_dos_drive_prefix(path))
89 return 2 + (path[2] == '/');
90 return *path == '/';
91}
92
b2cb9425
JH
93int safe_create_leading_directories(char *path)
94{
8385abfd 95 char *pos = path + offset_1st_component(path);
67d42212
JR
96 struct stat st;
97
b2cb9425
JH
98 while (pos) {
99 pos = strchr(pos, '/');
100 if (!pos)
101 break;
5f0bdf50
JH
102 while (*++pos == '/')
103 ;
104 if (!*pos)
105 break;
106 *--pos = '\0';
67d42212
JR
107 if (!stat(path, &st)) {
108 /* path exists */
109 if (!S_ISDIR(st.st_mode)) {
b2cb9425 110 *pos = '/';
67d42212 111 return -3;
b2cb9425 112 }
457f06d6 113 }
67d42212
JR
114 else if (mkdir(path, 0777)) {
115 *pos = '/';
116 return -1;
117 }
457f06d6
JS
118 else if (adjust_shared_perm(path)) {
119 *pos = '/';
120 return -2;
121 }
b2cb9425
JH
122 *pos++ = '/';
123 }
124 return 0;
125}
723c31fe 126
8e21d63b
JK
127int safe_create_leading_directories_const(const char *path)
128{
129 /* path points to cache entries, so xstrdup before messing with it */
130 char *buf = xstrdup(path);
131 int result = safe_create_leading_directories(buf);
132 free(buf);
133 return result;
134}
135
3bfaf018 136char *sha1_to_hex(const unsigned char *sha1)
0fcfd160 137{
dcb3450f
LT
138 static int bufno;
139 static char hexbuffer[4][50];
0fcfd160 140 static const char hex[] = "0123456789abcdef";
dcb3450f 141 char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
0fcfd160
LT
142 int i;
143
144 for (i = 0; i < 20; i++) {
145 unsigned int val = *sha1++;
146 *buf++ = hex[val >> 4];
147 *buf++ = hex[val & 0xf];
148 }
1e80e044
JS
149 *buf = '\0';
150
0fcfd160
LT
151 return buffer;
152}
153
ace1534d
JH
154static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
155{
156 int i;
157 for (i = 0; i < 20; i++) {
158 static char hex[] = "0123456789abcdef";
159 unsigned int val = sha1[i];
160 char *pos = pathbuf + i*2 + (i > 0);
161 *pos++ = hex[val >> 4];
162 *pos = hex[val & 0xf];
163 }
164}
165
0fcfd160
LT
166/*
167 * NOTE! This returns a statically allocated buffer, so you have to be
790296fd 168 * careful about using it. Do an "xstrdup()" if you need to save the
0fcfd160 169 * filename.
ace1534d
JH
170 *
171 * Also note that this returns the location for creating. Reading
172 * SHA1 file can happen from any alternate directory listed in the
d19938ab 173 * DB_ENVIRONMENT environment variable if it is not found in
ace1534d 174 * the primary object database.
0fcfd160
LT
175 */
176char *sha1_file_name(const unsigned char *sha1)
177{
0fcfd160
LT
178 static char *name, *base;
179
180 if (!base) {
d19938ab 181 const char *sha1_file_directory = get_object_directory();
0fcfd160 182 int len = strlen(sha1_file_directory);
812666c8 183 base = xmalloc(len + 60);
0fcfd160
LT
184 memcpy(base, sha1_file_directory, len);
185 memset(base+len, 0, 60);
186 base[len] = '/';
187 base[len+3] = '/';
188 name = base + len + 1;
189 }
ace1534d 190 fill_sha1_path(name, sha1);
0fcfd160
LT
191 return base;
192}
193
633f43e1 194static char *sha1_get_pack_name(const unsigned char *sha1,
6eec46bd 195 char **name, char **base, const char *which)
bf592c50
DB
196{
197 static const char hex[] = "0123456789abcdef";
633f43e1 198 char *buf;
bf592c50
DB
199 int i;
200
633f43e1 201 if (!*base) {
bf592c50
DB
202 const char *sha1_file_directory = get_object_directory();
203 int len = strlen(sha1_file_directory);
633f43e1 204 *base = xmalloc(len + 60);
6eec46bd
JH
205 sprintf(*base, "%s/pack/pack-1234567890123456789012345678901234567890.%s",
206 sha1_file_directory, which);
633f43e1 207 *name = *base + len + 11;
bf592c50
DB
208 }
209
633f43e1 210 buf = *name;
bf592c50
DB
211
212 for (i = 0; i < 20; i++) {
213 unsigned int val = *sha1++;
214 *buf++ = hex[val >> 4];
215 *buf++ = hex[val & 0xf];
216 }
a6080a0a 217
633f43e1 218 return *base;
bf592c50
DB
219}
220
633f43e1 221char *sha1_pack_name(const unsigned char *sha1)
bf592c50 222{
633f43e1 223 static char *name, *base;
bf592c50 224
6eec46bd 225 return sha1_get_pack_name(sha1, &name, &base, "pack");
633f43e1 226}
bf592c50 227
633f43e1
HO
228char *sha1_pack_index_name(const unsigned char *sha1)
229{
230 static char *name, *base;
a6080a0a 231
6eec46bd 232 return sha1_get_pack_name(sha1, &name, &base, "idx");
bf592c50
DB
233}
234
d5a63b99
JH
235struct alternate_object_database *alt_odb_list;
236static struct alternate_object_database **alt_odb_tail;
ace1534d 237
c2f493a4
MW
238static void read_info_alternates(const char * alternates, int depth);
239
ddd5d056
JH
240/*
241 * Prepare alternate object database registry.
d5a63b99
JH
242 *
243 * The variable alt_odb_list points at the list of struct
244 * alternate_object_database. The elements on this list come from
245 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
246 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
247 * whose contents is similar to that environment variable but can be
248 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
249 * contains "/the/directory/corresponding/to/.git/objects/...", while
250 * its name points just after the slash at the end of ".git/objects/"
251 * in the example above, and has enough space to hold 40-byte hex
252 * SHA1, an extra slash for the first level indirection, and the
253 * terminating NUL.
ddd5d056 254 */
c2f493a4 255static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
ace1534d 256{
1494e038 257 const char *objdir = get_object_directory();
c2f493a4
MW
258 struct alternate_object_database *ent;
259 struct alternate_object_database *alt;
260 /* 43 = 40-byte + 2 '/' + terminating NUL */
261 int pfxlen = len;
262 int entlen = pfxlen + 43;
ccfd3e99 263 int base_len = -1;
d5a63b99 264
85dadc38 265 if (!is_absolute_path(entry) && relative_base) {
c2f493a4
MW
266 /* Relative alt-odb */
267 if (base_len < 0)
268 base_len = strlen(relative_base) + 1;
269 entlen += base_len;
270 pfxlen += base_len;
271 }
272 ent = xmalloc(sizeof(*ent) + entlen);
273
85dadc38 274 if (!is_absolute_path(entry) && relative_base) {
c2f493a4
MW
275 memcpy(ent->base, relative_base, base_len - 1);
276 ent->base[base_len - 1] = '/';
277 memcpy(ent->base + base_len, entry, len);
278 }
279 else
280 memcpy(ent->base, entry, pfxlen);
281
282 ent->name = ent->base + pfxlen + 1;
283 ent->base[pfxlen + 3] = '/';
284 ent->base[pfxlen] = ent->base[entlen-1] = 0;
285
286 /* Detect cases where alternate disappeared */
90b4a71c 287 if (!is_directory(ent->base)) {
c2f493a4
MW
288 error("object directory %s does not exist; "
289 "check .git/objects/info/alternates.",
290 ent->base);
291 free(ent);
292 return -1;
293 }
294
295 /* Prevent the common mistake of listing the same
296 * thing twice, or object directory itself.
297 */
298 for (alt = alt_odb_list; alt; alt = alt->next) {
299 if (!memcmp(ent->base, alt->base, pfxlen)) {
300 free(ent);
301 return -1;
302 }
303 }
304 if (!memcmp(ent->base, objdir, pfxlen)) {
305 free(ent);
306 return -1;
307 }
308
309 /* add the alternate entry */
310 *alt_odb_tail = ent;
311 alt_odb_tail = &(ent->next);
312 ent->next = NULL;
313
314 /* recursively add alternates */
315 read_info_alternates(ent->base, depth + 1);
316
317 ent->base[pfxlen] = '/';
318
319 return 0;
320}
321
322static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
323 const char *relative_base, int depth)
324{
325 const char *cp, *last;
326
327 if (depth > 5) {
328 error("%s: ignoring alternate object stores, nesting too deep.",
329 relative_base);
330 return;
331 }
332
d5a63b99 333 last = alt;
9577e7e3
JH
334 while (last < ep) {
335 cp = last;
336 if (cp < ep && *cp == '#') {
337 while (cp < ep && *cp != sep)
338 cp++;
339 last = cp + 1;
340 continue;
341 }
c2f493a4
MW
342 while (cp < ep && *cp != sep)
343 cp++;
d5a63b99 344 if (last != cp) {
85dadc38 345 if (!is_absolute_path(last) && depth) {
c2f493a4
MW
346 error("%s: ignoring relative alternate object store %s",
347 relative_base, last);
348 } else {
349 link_alt_odb_entry(last, cp - last,
350 relative_base, depth);
1494e038 351 }
d5a63b99 352 }
9577e7e3 353 while (cp < ep && *cp == sep)
d5a63b99
JH
354 cp++;
355 last = cp;
9577e7e3 356 }
d5a63b99
JH
357}
358
c2f493a4 359static void 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);
d5a63b99
JH
372 fd = open(path, O_RDONLY);
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
dc49cd76 383 link_alt_odb_entries(map, 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);
bef70b22
DB
392 char *alt = mkpath("%s/objects\n", reference);
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)
397 link_alt_odb_entries(alt, alt + strlen(alt), '\n', NULL, 0);
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;
80ba074f 421 link_alt_odb_entries(alt, 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;
454static size_t peak_pack_mapped;
60bb8b14 455static size_t pack_mapped;
9a217f2a 456struct packed_git *packed_git;
1f688557 457
b79d18c9 458void pack_report(void)
a53128b6
SP
459{
460 fprintf(stderr,
e05db0fd
PR
461 "pack_report: getpagesize() = %10" SZ_FMT "\n"
462 "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
463 "pack_report: core.packedGitLimit = %10" SZ_FMT "\n",
9e42d6a1
SP
464 sz_fmt(getpagesize()),
465 sz_fmt(packed_git_window_size),
466 sz_fmt(packed_git_limit));
a53128b6
SP
467 fprintf(stderr,
468 "pack_report: pack_used_ctr = %10u\n"
469 "pack_report: pack_mmap_calls = %10u\n"
470 "pack_report: pack_open_windows = %10u / %10u\n"
e05db0fd
PR
471 "pack_report: pack_mapped = "
472 "%10" SZ_FMT " / %10" SZ_FMT "\n",
a53128b6
SP
473 pack_used_ctr,
474 pack_mmap_calls,
475 pack_open_windows, peak_pack_open_windows,
9e42d6a1 476 sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped));
a53128b6
SP
477}
478
42873078 479static int check_packed_git_idx(const char *path, struct packed_git *p)
1f688557
JH
480{
481 void *idx_map;
42873078 482 struct pack_idx_header *hdr;
dc49cd76 483 size_t idx_size;
74e34e1f 484 uint32_t version, nr, i, *index;
e93ec6f9 485 int fd = open(path, O_RDONLY);
1f688557 486 struct stat st;
42873078 487
1f688557
JH
488 if (fd < 0)
489 return -1;
490 if (fstat(fd, &st)) {
491 close(fd);
492 return -1;
493 }
dc49cd76 494 idx_size = xsize_t(st.st_size);
2d88451b
SP
495 if (idx_size < 4 * 256 + 20 + 20) {
496 close(fd);
497 return error("index file %s is too small", path);
498 }
c4712e45 499 idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
1f688557 500 close(fd);
1f688557 501
42873078
NP
502 hdr = idx_map;
503 if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) {
74e34e1f
NP
504 version = ntohl(hdr->idx_version);
505 if (version < 2 || version > 2) {
506 munmap(idx_map, idx_size);
6e1c2344 507 return error("index file %s is version %"PRIu32
74e34e1f
NP
508 " and is not supported by this binary"
509 " (try upgrading GIT to a newer version)",
510 path, version);
511 }
512 } else
513 version = 1;
df1b059d 514
1f688557 515 nr = 0;
42873078 516 index = idx_map;
74e34e1f
NP
517 if (version > 1)
518 index += 2; /* skip index header */
1f688557 519 for (i = 0; i < 256; i++) {
326bf396 520 uint32_t n = ntohl(index[i]);
2d88451b
SP
521 if (n < nr) {
522 munmap(idx_map, idx_size);
df1b059d 523 return error("non-monotonic index %s", path);
2d88451b 524 }
1f688557
JH
525 nr = n;
526 }
527
74e34e1f
NP
528 if (version == 1) {
529 /*
530 * Total size:
531 * - 256 index entries 4 bytes each
532 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
533 * - 20-byte SHA1 of the packfile
534 * - 20-byte SHA1 file checksum
535 */
536 if (idx_size != 4*256 + nr * 24 + 20 + 20) {
537 munmap(idx_map, idx_size);
eef427a0 538 return error("wrong index v1 file size in %s", path);
74e34e1f
NP
539 }
540 } else if (version == 2) {
541 /*
542 * Minimum size:
543 * - 8 bytes of header
544 * - 256 index entries 4 bytes each
545 * - 20-byte sha1 entry * nr
546 * - 4-byte crc entry * nr
547 * - 4-byte offset entry * nr
548 * - 20-byte SHA1 of the packfile
549 * - 20-byte SHA1 file checksum
550 * And after the 4-byte offset table might be a
551 * variable sized table containing 8-byte entries
552 * for offsets larger than 2^31.
553 */
554 unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20;
1164f1e4
LT
555 unsigned long max_size = min_size;
556 if (nr)
557 max_size += (nr - 1)*8;
558 if (idx_size < min_size || idx_size > max_size) {
74e34e1f 559 munmap(idx_map, idx_size);
eef427a0 560 return error("wrong index v2 file size in %s", path);
74e34e1f 561 }
7109c889
JH
562 if (idx_size != min_size &&
563 /*
564 * make sure we can deal with large pack offsets.
565 * 31-bit signed offset won't be enough, neither
566 * 32-bit unsigned one will be.
567 */
568 (sizeof(off_t) <= 4)) {
569 munmap(idx_map, idx_size);
570 return error("pack too large for current definition of off_t in %s", path);
74e34e1f 571 }
2d88451b 572 }
1f688557 573
74e34e1f 574 p->index_version = version;
42873078
NP
575 p->index_data = idx_map;
576 p->index_size = idx_size;
57059091 577 p->num_objects = nr;
1f688557
JH
578 return 0;
579}
580
bc8e478a 581int open_pack_index(struct packed_git *p)
d079837e
SP
582{
583 char *idx_name;
584 int ret;
585
586 if (p->index_data)
587 return 0;
588
589 idx_name = xstrdup(p->pack_name);
590 strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx");
591 ret = check_packed_git_idx(idx_name, p);
592 free(idx_name);
593 return ret;
594}
595
11daf39b
SP
596static void scan_windows(struct packed_git *p,
597 struct packed_git **lru_p,
598 struct pack_window **lru_w,
599 struct pack_window **lru_l)
1f688557 600{
11daf39b
SP
601 struct pack_window *w, *w_l;
602
603 for (w_l = NULL, w = p->windows; w; w = w->next) {
604 if (!w->inuse_cnt) {
605 if (!*lru_w || w->last_used < (*lru_w)->last_used) {
606 *lru_p = p;
607 *lru_w = w;
608 *lru_l = w_l;
54044bf8 609 }
54044bf8 610 }
11daf39b 611 w_l = w;
f9253394 612 }
11daf39b
SP
613}
614
d1efefa4 615static int unuse_one_window(struct packed_git *current, int keep_fd)
11daf39b
SP
616{
617 struct packed_git *p, *lru_p = NULL;
618 struct pack_window *lru_w = NULL, *lru_l = NULL;
619
620 if (current)
621 scan_windows(current, &lru_p, &lru_w, &lru_l);
622 for (p = packed_git; p; p = p->next)
623 scan_windows(p, &lru_p, &lru_w, &lru_l);
54044bf8
SP
624 if (lru_p) {
625 munmap(lru_w->base, lru_w->len);
626 pack_mapped -= lru_w->len;
627 if (lru_l)
628 lru_l->next = lru_w->next;
629 else {
630 lru_p->windows = lru_w->next;
d1efefa4 631 if (!lru_p->windows && lru_p->pack_fd != keep_fd) {
54044bf8
SP
632 close(lru_p->pack_fd);
633 lru_p->pack_fd = -1;
634 }
635 }
636 free(lru_w);
a53128b6 637 pack_open_windows--;
54044bf8
SP
638 return 1;
639 }
640 return 0;
f9253394
JH
641}
642
d1efefa4 643void release_pack_memory(size_t need, int fd)
97bfeb34
SP
644{
645 size_t cur = pack_mapped;
d1efefa4 646 while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd))
97bfeb34
SP
647 ; /* nothing */
648}
649
c9ced051
SP
650void close_pack_windows(struct packed_git *p)
651{
652 while (p->windows) {
653 struct pack_window *w = p->windows;
654
655 if (w->inuse_cnt)
656 die("pack '%s' still has open windows to it",
657 p->pack_name);
658 munmap(w->base, w->len);
659 pack_mapped -= w->len;
660 pack_open_windows--;
661 p->windows = w->next;
662 free(w);
663 }
664}
665
03e79c88 666void unuse_pack(struct pack_window **w_cursor)
f9253394 667{
03e79c88
SP
668 struct pack_window *w = *w_cursor;
669 if (w) {
670 w->inuse_cnt--;
671 *w_cursor = NULL;
672 }
1f688557
JH
673}
674
c74faea1
NP
675/*
676 * This is used by git-repack in case a newly created pack happens to
677 * contain the same set of objects as an existing one. In that case
678 * the resulting file might be different even if its name would be the
679 * same. It is best to close any reference to the old pack before it is
680 * replaced on disk. Of course no index pointers nor windows for given pack
681 * must subsist at this point. If ever objects from this pack are requested
682 * again, the new version of the pack will be reinitialized through
683 * reprepare_packed_git().
684 */
685void free_pack_by_name(const char *pack_name)
686{
687 struct packed_git *p, **pp = &packed_git;
688
689 while (*pp) {
690 p = *pp;
691 if (strcmp(pack_name, p->pack_name) == 0) {
fa3a0c94 692 clear_delta_base_cache();
c74faea1
NP
693 close_pack_windows(p);
694 if (p->pack_fd != -1)
695 close(p->pack_fd);
696 if (p->index_data)
697 munmap((void *)p->index_data, p->index_size);
698 free(p->bad_object_sha1);
699 *pp = p->next;
700 free(p);
701 return;
702 }
703 pp = &p->next;
704 }
705}
706
3cf8b462
SP
707/*
708 * Do not call this directly as this leaks p->pack_fd on error return;
709 * call open_packed_git() instead.
710 */
711static int open_packed_git_1(struct packed_git *p)
1f688557 712{
9bc879c1
SP
713 struct stat st;
714 struct pack_header hdr;
715 unsigned char sha1[20];
716 unsigned char *idx_sha1;
2c039da8 717 long fd_flag;
9bc879c1 718
d079837e
SP
719 if (!p->index_data && open_pack_index(p))
720 return error("packfile %s index unavailable", p->pack_name);
721
9bc879c1 722 p->pack_fd = open(p->pack_name, O_RDONLY);
fd73ccf2
JS
723 while (p->pack_fd < 0 && errno == EMFILE && unuse_one_window(p, -1))
724 p->pack_fd = open(p->pack_name, O_RDONLY);
9bc879c1 725 if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
072db278 726 return -1;
9bc879c1
SP
727
728 /* If we created the struct before we had the pack we lack size. */
bf592c50 729 if (!p->pack_size) {
bf592c50 730 if (!S_ISREG(st.st_mode))
072db278 731 return error("packfile %s not a regular file", p->pack_name);
bf592c50 732 p->pack_size = st.st_size;
9bc879c1 733 } else if (p->pack_size != st.st_size)
072db278 734 return error("packfile %s size changed", p->pack_name);
9bc879c1 735
2c039da8
JH
736 /* We leave these file descriptors open with sliding mmap;
737 * there is no point keeping them open across exec(), though.
738 */
739 fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
740 if (fd_flag < 0)
072db278 741 return error("cannot determine file descriptor flags");
2c039da8
JH
742 fd_flag |= FD_CLOEXEC;
743 if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
072db278 744 return error("cannot set FD_CLOEXEC");
2c039da8 745
9bc879c1 746 /* Verify we recognize this pack file format. */
e6e2bd62 747 if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
072db278 748 return error("file %s is far too short to be a packfile", p->pack_name);
9bc879c1 749 if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
072db278 750 return error("file %s is not a GIT packfile", p->pack_name);
9bc879c1 751 if (!pack_version_ok(hdr.hdr_version))
6e1c2344
RJ
752 return error("packfile %s is version %"PRIu32" and not"
753 " supported (try upgrading GIT to a newer version)",
9bc879c1
SP
754 p->pack_name, ntohl(hdr.hdr_version));
755
756 /* Verify the pack matches its index. */
57059091 757 if (p->num_objects != ntohl(hdr.hdr_entries))
6e1c2344
RJ
758 return error("packfile %s claims to have %"PRIu32" objects"
759 " while index indicates %"PRIu32" objects",
57059091
NP
760 p->pack_name, ntohl(hdr.hdr_entries),
761 p->num_objects);
9bc879c1 762 if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
072db278 763 return error("end of packfile %s is unavailable", p->pack_name);
e6e2bd62 764 if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
072db278 765 return error("packfile %s signature is unavailable", p->pack_name);
42873078 766 idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40;
9bc879c1 767 if (hashcmp(sha1, idx_sha1))
072db278
SP
768 return error("packfile %s does not match index", p->pack_name);
769 return 0;
9bc879c1
SP
770}
771
3cf8b462
SP
772static int open_packed_git(struct packed_git *p)
773{
774 if (!open_packed_git_1(p))
775 return 0;
776 if (p->pack_fd != -1) {
777 close(p->pack_fd);
778 p->pack_fd = -1;
779 }
780 return -1;
781}
782
c4001d92 783static int in_window(struct pack_window *win, off_t offset)
60bb8b14
SP
784{
785 /* We must promise at least 20 bytes (one hash) after the
786 * offset is available from this window, otherwise the offset
787 * is not actually in this window and a different window (which
788 * has that one hash excess) must be used. This is to support
789 * the object header and delta base parsing routines below.
790 */
791 off_t win_off = win->offset;
792 return win_off <= offset
793 && (offset + 20) <= (win_off + win->len);
794}
795
4b25d091 796unsigned char *use_pack(struct packed_git *p,
03e79c88 797 struct pack_window **w_cursor,
c4001d92 798 off_t offset,
03e79c88 799 unsigned int *left)
9bc879c1 800{
60bb8b14 801 struct pack_window *win = *w_cursor;
03e79c88 802
072db278
SP
803 if (p->pack_fd == -1 && open_packed_git(p))
804 die("packfile %s cannot be accessed", p->pack_name);
60bb8b14 805
a9d98a14 806 /* Since packfiles end in a hash of their content and it's
60bb8b14
SP
807 * pointless to ask for an offset into the middle of that
808 * hash, and the in_window function above wouldn't match
809 * don't allow an offset too close to the end of the file.
810 */
811 if (offset > (p->pack_size - 20))
812 die("offset beyond end of packfile (truncated pack?)");
813
814 if (!win || !in_window(win, offset)) {
815 if (win)
816 win->inuse_cnt--;
817 for (win = p->windows; win; win = win->next) {
818 if (in_window(win, offset))
819 break;
820 }
821 if (!win) {
78a28df9 822 size_t window_align = packed_git_window_size / 2;
dc49cd76 823 off_t len;
60bb8b14 824 win = xcalloc(1, sizeof(*win));
78a28df9 825 win->offset = (offset / window_align) * window_align;
dc49cd76
SP
826 len = p->pack_size - win->offset;
827 if (len > packed_git_window_size)
828 len = packed_git_window_size;
829 win->len = (size_t)len;
60bb8b14 830 pack_mapped += win->len;
11daf39b 831 while (packed_git_limit < pack_mapped
d1efefa4 832 && unuse_one_window(p, p->pack_fd))
60bb8b14 833 ; /* nothing */
c4712e45 834 win->base = xmmap(NULL, win->len,
60bb8b14
SP
835 PROT_READ, MAP_PRIVATE,
836 p->pack_fd, win->offset);
837 if (win->base == MAP_FAILED)
73b4e4be
SP
838 die("packfile %s cannot be mapped: %s",
839 p->pack_name,
840 strerror(errno));
a53128b6
SP
841 pack_mmap_calls++;
842 pack_open_windows++;
843 if (pack_mapped > peak_pack_mapped)
844 peak_pack_mapped = pack_mapped;
845 if (pack_open_windows > peak_pack_open_windows)
846 peak_pack_open_windows = pack_open_windows;
60bb8b14
SP
847 win->next = p->windows;
848 p->windows = win;
849 }
1f688557 850 }
03e79c88
SP
851 if (win != *w_cursor) {
852 win->last_used = pack_used_ctr++;
853 win->inuse_cnt++;
854 *w_cursor = win;
855 }
60bb8b14 856 offset -= win->offset;
03e79c88 857 if (left)
dc49cd76 858 *left = win->len - xsize_t(offset);
03e79c88 859 return win->base + offset;
1f688557
JH
860}
861
27d69a46
NP
862static struct packed_git *alloc_packed_git(int extra)
863{
864 struct packed_git *p = xmalloc(sizeof(*p) + extra);
865 memset(p, 0, sizeof(*p));
866 p->pack_fd = -1;
867 return p;
868}
869
42873078 870struct packed_git *add_packed_git(const char *path, int path_len, int local)
1f688557
JH
871{
872 struct stat st;
27d69a46 873 struct packed_git *p = alloc_packed_git(path_len + 2);
1f688557 874
42873078
NP
875 /*
876 * Make sure a corresponding .pack file exists and that
877 * the index looks sane.
878 */
879 path_len -= strlen(".idx");
27d69a46
NP
880 if (path_len < 1) {
881 free(p);
1f688557 882 return NULL;
27d69a46 883 }
42873078 884 memcpy(p->pack_name, path, path_len);
8d25931d
BC
885
886 strcpy(p->pack_name + path_len, ".keep");
887 if (!access(p->pack_name, F_OK))
888 p->pack_keep = 1;
889
42873078 890 strcpy(p->pack_name + path_len, ".pack");
d079837e 891 if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
42873078 892 free(p);
1f688557
JH
893 return NULL;
894 }
42873078 895
1f688557
JH
896 /* ok, it looks sane as far as we can check without
897 * actually mapping the pack file.
898 */
1f688557 899 p->pack_size = st.st_size;
9d835df2 900 p->pack_local = local;
b867092f 901 p->mtime = st.st_mtime;
42873078
NP
902 if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1))
903 hashclr(p->sha1);
1f688557
JH
904 return p;
905}
906
bf592c50 907struct packed_git *parse_pack_index(unsigned char *sha1)
c508df5e 908{
79c6dca4 909 const char *idx_path = sha1_pack_index_name(sha1);
42873078 910 const char *path = sha1_pack_name(sha1);
27d69a46 911 struct packed_git *p = alloc_packed_git(strlen(path) + 1);
bf592c50 912
27d69a46
NP
913 strcpy(p->pack_name, path);
914 hashcpy(p->sha1, sha1);
42873078
NP
915 if (check_packed_git_idx(idx_path, p)) {
916 free(p);
bf592c50 917 return NULL;
42873078 918 }
bf592c50 919
bf592c50
DB
920 return p;
921}
922
923void install_packed_git(struct packed_git *pack)
924{
925 pack->next = packed_git;
926 packed_git = pack;
927}
928
9d835df2 929static void prepare_packed_git_one(char *objdir, int local)
1f688557 930{
9cb18f56
JM
931 /* Ensure that this buffer is large enough so that we can
932 append "/pack/" without clobbering the stack even if
933 strlen(objdir) were PATH_MAX. */
934 char path[PATH_MAX + 1 + 4 + 1 + 1];
1f688557
JH
935 int len;
936 DIR *dir;
937 struct dirent *de;
938
939 sprintf(path, "%s/pack", objdir);
940 len = strlen(path);
941 dir = opendir(path);
fd73ccf2
JS
942 while (!dir && errno == EMFILE && unuse_one_window(packed_git, -1))
943 dir = opendir(path);
b5b16990 944 if (!dir) {
26125f6b 945 if (errno != ENOENT)
bd2afde8 946 error("unable to open object pack directory: %s: %s",
26125f6b 947 path, strerror(errno));
1f688557 948 return;
b5b16990 949 }
1f688557
JH
950 path[len++] = '/';
951 while ((de = readdir(dir)) != NULL) {
952 int namelen = strlen(de->d_name);
953 struct packed_git *p;
954
5bb1cda5 955 if (!has_extension(de->d_name, ".idx"))
1f688557
JH
956 continue;
957
9cb18f56
JM
958 if (len + namelen + 1 > sizeof(path))
959 continue;
960
54a15a8d 961 /* Don't reopen a pack we already have. */
1f688557 962 strcpy(path + len, de->d_name);
86f7780c
JK
963 for (p = packed_git; p; p = p->next) {
964 if (!memcmp(path, p->pack_name, len + namelen - 4))
965 break;
966 }
967 if (p)
968 continue;
54a15a8d
SP
969 /* See if it really is a valid .idx file with corresponding
970 * .pack file that we can map.
971 */
9d835df2 972 p = add_packed_git(path, len + namelen, local);
1f688557
JH
973 if (!p)
974 continue;
625e9421 975 install_packed_git(p);
1f688557 976 }
5b35bcd5 977 closedir(dir);
1f688557
JH
978}
979
b867092f
JH
980static int sort_pack(const void *a_, const void *b_)
981{
982 struct packed_git *a = *((struct packed_git **)a_);
983 struct packed_git *b = *((struct packed_git **)b_);
984 int st;
985
986 /*
987 * Local packs tend to contain objects specific to our
988 * variant of the project than remote ones. In addition,
989 * remote ones could be on a network mounted filesystem.
990 * Favor local ones for these reasons.
991 */
992 st = a->pack_local - b->pack_local;
993 if (st)
994 return -st;
995
996 /*
997 * Younger packs tend to contain more recent objects,
998 * and more recent objects tend to get accessed more
999 * often.
1000 */
1001 if (a->mtime < b->mtime)
1002 return 1;
1003 else if (a->mtime == b->mtime)
1004 return 0;
1005 return -1;
1006}
1007
1008static void rearrange_packed_git(void)
1009{
1010 struct packed_git **ary, *p;
1011 int i, n;
1012
1013 for (n = 0, p = packed_git; p; p = p->next)
1014 n++;
1015 if (n < 2)
1016 return;
1017
1018 /* prepare an array of packed_git for easier sorting */
1019 ary = xcalloc(n, sizeof(struct packed_git *));
1020 for (n = 0, p = packed_git; p; p = p->next)
1021 ary[n++] = p;
1022
1023 qsort(ary, n, sizeof(struct packed_git *), sort_pack);
1024
1025 /* link them back again */
1026 for (i = 0; i < n - 1; i++)
1027 ary[i]->next = ary[i + 1];
1028 ary[n - 1]->next = NULL;
1029 packed_git = ary[0];
1030
1031 free(ary);
1032}
1033
637cdd9d 1034static int prepare_packed_git_run_once = 0;
9a217f2a 1035void prepare_packed_git(void)
1f688557 1036{
d5a63b99 1037 struct alternate_object_database *alt;
1f688557 1038
637cdd9d 1039 if (prepare_packed_git_run_once)
1f688557 1040 return;
9d835df2 1041 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 1042 prepare_alt_odb();
d5a63b99 1043 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 1044 alt->name[-1] = 0;
9d835df2 1045 prepare_packed_git_one(alt->base, 0);
1494e038 1046 alt->name[-1] = '/';
1f688557 1047 }
b867092f 1048 rearrange_packed_git();
637cdd9d
JK
1049 prepare_packed_git_run_once = 1;
1050}
1051
fc04c412 1052void reprepare_packed_git(void)
637cdd9d 1053{
4b480c67 1054 discard_revindex();
637cdd9d
JK
1055 prepare_packed_git_run_once = 0;
1056 prepare_packed_git();
1f688557
JH
1057}
1058
8eca0b47
NP
1059static void mark_bad_packed_object(struct packed_git *p,
1060 const unsigned char *sha1)
1061{
1062 unsigned i;
1063 for (i = 0; i < p->num_bad_objects; i++)
1064 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1065 return;
1066 p->bad_object_sha1 = xrealloc(p->bad_object_sha1, 20 * (p->num_bad_objects + 1));
1067 hashcpy(p->bad_object_sha1 + 20 * p->num_bad_objects, sha1);
1068 p->num_bad_objects++;
1069}
1070
ac939109
NP
1071static int has_packed_and_bad(const unsigned char *sha1)
1072{
1073 struct packed_git *p;
1074 unsigned i;
1075
1076 for (p = packed_git; p; p = p->next)
1077 for (i = 0; i < p->num_bad_objects; i++)
1078 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1079 return 1;
1080 return 0;
1081}
1082
5d6ccf5c 1083int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
0fcfd160
LT
1084{
1085 unsigned char real_sha1[20];
7cfb5f36 1086 hash_sha1_file(map, size, type, real_sha1);
a89fccd2 1087 return hashcmp(sha1, real_sha1) ? -1 : 0;
0fcfd160
LT
1088}
1089
44d1c19e
LT
1090static int git_open_noatime(const char *name)
1091{
1092 static int sha1_file_open_flag = O_NOATIME;
1093 int fd = open(name, O_RDONLY | sha1_file_open_flag);
1094
1095 /* Might the failure be due to O_NOATIME? */
1096 if (fd < 0 && errno != ENOENT && sha1_file_open_flag) {
1097 fd = open(name, O_RDONLY);
1098 if (fd >= 0)
1099 sha1_file_open_flag = 0;
1100 }
1101 return fd;
1102}
1103
1104static int open_sha1_file(const unsigned char *sha1)
1105{
1106 int fd;
1107 char *name = sha1_file_name(sha1);
1108 struct alternate_object_database *alt;
1109
1110 fd = git_open_noatime(name);
1111 if (fd >= 0)
1112 return fd;
1113
1114 prepare_alt_odb();
1115 errno = ENOENT;
1116 for (alt = alt_odb_list; alt; alt = alt->next) {
1117 name = alt->name;
1118 fill_sha1_path(name, sha1);
1119 fd = git_open_noatime(alt->base);
1120 if (fd >= 0)
1121 return fd;
1122 }
1123 return -1;
1124}
1125
4175e9e3 1126static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
0fcfd160 1127{
0fcfd160 1128 void *map;
144bde78 1129 int fd;
ace1534d 1130
44d1c19e
LT
1131 fd = open_sha1_file(sha1);
1132 map = NULL;
1133 if (fd >= 0) {
1134 struct stat st;
0fcfd160 1135
44d1c19e
LT
1136 if (!fstat(fd, &st)) {
1137 *size = xsize_t(st.st_size);
1138 map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
144bde78 1139 }
44d1c19e 1140 close(fd);
0fcfd160 1141 }
0fcfd160
LT
1142 return map;
1143}
1144
726f852b 1145static int legacy_loose_object(unsigned char *map)
bb6b8e4f
JH
1146{
1147 unsigned int word;
1148
1149 /*
1150 * Is it a zlib-compressed buffer? If so, the first byte
1151 * must be 0x78 (15-bit window size, deflated), and the
1152 * first 16-bit word is evenly divisible by 31
1153 */
1154 word = (map[0] << 8) + map[1];
1155 if (map[0] == 0x78 && !(word % 31))
1156 return 1;
1157 else
1158 return 0;
1159}
1160
09ded04b
NP
1161unsigned long unpack_object_header_buffer(const unsigned char *buf,
1162 unsigned long len, enum object_type *type, unsigned long *sizep)
c4483576 1163{
ad1ed5ee 1164 unsigned shift;
93821bd9 1165 unsigned char c;
93821bd9 1166 unsigned long size;
ad1ed5ee
JH
1167 unsigned long used = 0;
1168
1169 c = buf[used++];
1170 *type = (c >> 4) & 7;
1171 size = c & 15;
1172 shift = 4;
1173 while (c & 0x80) {
09ded04b
NP
1174 if (len <= used || sizeof(long) * 8 <= shift) {
1175 error("bad object header");
ad1ed5ee 1176 return 0;
09ded04b 1177 }
ad1ed5ee
JH
1178 c = buf[used++];
1179 size += (c & 0x7f) << shift;
1180 shift += 7;
1181 }
1182 *sizep = size;
1183 return used;
1184}
1185
1186static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
1187{
1188 unsigned long size, used;
1189 static const char valid_loose_object_type[8] = {
1190 0, /* OBJ_EXT */
1191 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
1192 0, /* "delta" and others are invalid in a loose object */
93821bd9 1193 };
ad1ed5ee 1194 enum object_type type;
93821bd9 1195
c4483576
LT
1196 /* Get the data stream */
1197 memset(stream, 0, sizeof(*stream));
1198 stream->next_in = map;
1199 stream->avail_in = mapsize;
1200 stream->next_out = buffer;
93821bd9
LT
1201 stream->avail_out = bufsiz;
1202
bb6b8e4f 1203 if (legacy_loose_object(map)) {
39c68542
LT
1204 git_inflate_init(stream);
1205 return git_inflate(stream, 0);
93821bd9
LT
1206 }
1207
726f852b
NP
1208
1209 /*
1210 * There used to be a second loose object header format which
1211 * was meant to mimic the in-pack format, allowing for direct
1212 * copy of the object data. This format turned up not to be
1213 * really worth it and we don't write it any longer. But we
1214 * can still read it.
1215 */
09ded04b 1216 used = unpack_object_header_buffer(map, mapsize, &type, &size);
ad1ed5ee 1217 if (!used || !valid_loose_object_type[type])
93821bd9 1218 return -1;
ad1ed5ee
JH
1219 map += used;
1220 mapsize -= used;
93821bd9
LT
1221
1222 /* Set up the stream for the rest.. */
1223 stream->next_in = map;
1224 stream->avail_in = mapsize;
39c68542 1225 git_inflate_init(stream);
93821bd9
LT
1226
1227 /* And generate the fake traditional header */
ad1ed5ee 1228 stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
df843662 1229 typename(type), size);
93821bd9 1230 return 0;
c4483576
LT
1231}
1232
7efbff75 1233static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
5180cacc
LT
1234{
1235 int bytes = strlen(buffer) + 1;
d565b341 1236 unsigned char *buf = xmalloc(1+size);
93821bd9 1237 unsigned long n;
7efbff75 1238 int status = Z_OK;
5180cacc 1239
93821bd9
LT
1240 n = stream->total_out - bytes;
1241 if (n > size)
1242 n = size;
1243 memcpy(buf, (char *) buffer + bytes, n);
1244 bytes = n;
456cdf6e
LT
1245 if (bytes <= size) {
1246 /*
1247 * The above condition must be (bytes <= size), not
1248 * (bytes < size). In other words, even though we
1249 * expect no more output and set avail_out to zer0,
1250 * the input zlib stream may have bytes that express
1251 * "this concludes the stream", and we *do* want to
1252 * eat that input.
1253 *
1254 * Otherwise we would not be able to test that we
1255 * consumed all the input to reach the expected size;
1256 * we also want to check that zlib tells us that all
1257 * went well with status == Z_STREAM_END at the end.
1258 */
5180cacc
LT
1259 stream->next_out = buf + bytes;
1260 stream->avail_out = size - bytes;
7efbff75 1261 while (status == Z_OK)
39c68542 1262 status = git_inflate(stream, Z_FINISH);
5180cacc
LT
1263 }
1264 buf[size] = 0;
456cdf6e 1265 if (status == Z_STREAM_END && !stream->avail_in) {
39c68542 1266 git_inflate_end(stream);
7efbff75
JH
1267 return buf;
1268 }
1269
1270 if (status < 0)
1271 error("corrupt loose object '%s'", sha1_to_hex(sha1));
1272 else if (stream->avail_in)
1273 error("garbage at end of loose object '%s'",
1274 sha1_to_hex(sha1));
1275 free(buf);
1276 return NULL;
5180cacc
LT
1277}
1278
1279/*
1280 * We used to just use "sscanf()", but that's actually way
1281 * too permissive for what we want to check. So do an anal
1282 * object header parse by hand.
1283 */
21666f1a 1284static int parse_sha1_header(const char *hdr, unsigned long *sizep)
5180cacc 1285{
21666f1a 1286 char type[10];
5180cacc
LT
1287 int i;
1288 unsigned long size;
1289
1290 /*
a6080a0a 1291 * The type can be at most ten bytes (including the
5180cacc 1292 * terminating '\0' that we add), and is followed by
21666f1a 1293 * a space.
5180cacc 1294 */
21666f1a 1295 i = 0;
5180cacc
LT
1296 for (;;) {
1297 char c = *hdr++;
1298 if (c == ' ')
1299 break;
21666f1a
NP
1300 type[i++] = c;
1301 if (i >= sizeof(type))
5180cacc 1302 return -1;
5180cacc 1303 }
21666f1a 1304 type[i] = 0;
5180cacc
LT
1305
1306 /*
1307 * The length must follow immediately, and be in canonical
1308 * decimal format (ie "010" is not valid).
1309 */
1310 size = *hdr++ - '0';
1311 if (size > 9)
1312 return -1;
1313 if (size) {
1314 for (;;) {
1315 unsigned long c = *hdr - '0';
1316 if (c > 9)
1317 break;
1318 hdr++;
1319 size = size * 10 + c;
1320 }
1321 }
1322 *sizep = size;
1323
1324 /*
1325 * The length must be followed by a zero byte
1326 */
21666f1a 1327 return *hdr ? -1 : type_from_string(type);
5180cacc
LT
1328}
1329
7efbff75 1330static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
0fcfd160 1331{
5180cacc 1332 int ret;
0fcfd160 1333 z_stream stream;
5180cacc 1334 char hdr[8192];
0fcfd160 1335
5180cacc 1336 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
21666f1a 1337 if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
0fcfd160
LT
1338 return NULL;
1339
7efbff75 1340 return unpack_sha1_rest(&stream, hdr, *size, sha1);
0fcfd160
LT
1341}
1342
54dab52a
NP
1343unsigned long get_size_from_delta(struct packed_git *p,
1344 struct pack_window **w_curs,
1345 off_t curpos)
1346{
1347 const unsigned char *data;
1348 unsigned char delta_head[20], *in;
1349 z_stream stream;
1350 int st;
1351
1352 memset(&stream, 0, sizeof(stream));
1353 stream.next_out = delta_head;
1354 stream.avail_out = sizeof(delta_head);
1355
39c68542 1356 git_inflate_init(&stream);
54dab52a
NP
1357 do {
1358 in = use_pack(p, w_curs, curpos, &stream.avail_in);
1359 stream.next_in = in;
39c68542 1360 st = git_inflate(&stream, Z_FINISH);
54dab52a
NP
1361 curpos += stream.next_in - in;
1362 } while ((st == Z_OK || st == Z_BUF_ERROR) &&
1363 stream.total_out < sizeof(delta_head));
39c68542 1364 git_inflate_end(&stream);
3d77d877
NP
1365 if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head)) {
1366 error("delta data unpack-initial failed");
1367 return 0;
1368 }
54dab52a
NP
1369
1370 /* Examine the initial part of the delta to figure out
1371 * the result size.
1372 */
1373 data = delta_head;
1374
1375 /* ignore base size */
1376 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1377
1378 /* Read the result size */
1379 return get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
1380}
1381
c4001d92 1382static off_t get_delta_base(struct packed_git *p,
03e79c88 1383 struct pack_window **w_curs,
c4001d92 1384 off_t *curpos,
21666f1a 1385 enum object_type type,
c4001d92 1386 off_t delta_obj_offset)
eb32d236 1387{
2b87c45b 1388 unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
c4001d92 1389 off_t base_offset;
eb32d236 1390
8d8a4ea5
SP
1391 /* use_pack() assured us we have [base_info, base_info + 20)
1392 * as a range that we can look at without walking off the
1393 * end of the mapped window. Its actually the hash size
1394 * that is assured. An OFS_DELTA longer than the hash size
1395 * is stupid, as then a REF_DELTA would be smaller to store.
1396 */
21666f1a 1397 if (type == OBJ_OFS_DELTA) {
eb32d236
NP
1398 unsigned used = 0;
1399 unsigned char c = base_info[used++];
1400 base_offset = c & 127;
1401 while (c & 128) {
1402 base_offset += 1;
8723f216 1403 if (!base_offset || MSB(base_offset, 7))
8eca0b47 1404 return 0; /* overflow */
eb32d236
NP
1405 c = base_info[used++];
1406 base_offset = (base_offset << 7) + (c & 127);
1407 }
1408 base_offset = delta_obj_offset - base_offset;
d8f32556 1409 if (base_offset <= 0 || base_offset >= delta_obj_offset)
8eca0b47 1410 return 0; /* out of bound */
2b87c45b 1411 *curpos += used;
21666f1a 1412 } else if (type == OBJ_REF_DELTA) {
eb32d236
NP
1413 /* The base entry _must_ be in the same pack */
1414 base_offset = find_pack_entry_one(base_info, p);
2b87c45b 1415 *curpos += 20;
eb32d236
NP
1416 } else
1417 die("I am totally screwed");
2b87c45b 1418 return base_offset;
eb32d236
NP
1419}
1420
f3bf9224 1421/* forward declaration for a mutually recursive function */
c4001d92 1422static int packed_object_info(struct packed_git *p, off_t offset,
21666f1a 1423 unsigned long *sizep);
f3bf9224 1424
43057304 1425static int packed_delta_info(struct packed_git *p,
03e79c88 1426 struct pack_window **w_curs,
c4001d92 1427 off_t curpos,
21666f1a 1428 enum object_type type,
c4001d92 1429 off_t obj_offset,
43057304 1430 unsigned long *sizep)
5db47c2b 1431{
c4001d92 1432 off_t base_offset;
f3bf9224 1433
21666f1a 1434 base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
3d77d877
NP
1435 if (!base_offset)
1436 return OBJ_BAD;
21666f1a 1437 type = packed_object_info(p, base_offset, NULL);
3d77d877 1438 if (type <= OBJ_NONE) {
08698b1e
NP
1439 struct revindex_entry *revidx;
1440 const unsigned char *base_sha1;
1441 revidx = find_pack_revindex(p, base_offset);
1442 if (!revidx)
1443 return OBJ_BAD;
1444 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
3d77d877
NP
1445 mark_bad_packed_object(p, base_sha1);
1446 type = sha1_object_info(base_sha1, NULL);
1447 if (type <= OBJ_NONE)
1448 return OBJ_BAD;
1449 }
f3bf9224 1450
c62266f3
JH
1451 /* We choose to only get the type of the base object and
1452 * ignore potentially corrupt pack file that expects the delta
1453 * based on a base with a wrong size. This saves tons of
1454 * inflate() calls.
1455 */
3d77d877 1456 if (sizep) {
54dab52a 1457 *sizep = get_size_from_delta(p, w_curs, curpos);
3d77d877
NP
1458 if (*sizep == 0)
1459 type = OBJ_BAD;
1460 }
21666f1a
NP
1461
1462 return type;
5db47c2b
JH
1463}
1464
2b87c45b
NP
1465static int unpack_object_header(struct packed_git *p,
1466 struct pack_window **w_curs,
c4001d92 1467 off_t *curpos,
2b87c45b 1468 unsigned long *sizep)
a733cb60 1469{
03e79c88
SP
1470 unsigned char *base;
1471 unsigned int left;
ad1ed5ee 1472 unsigned long used;
2b87c45b 1473 enum object_type type;
a733cb60 1474
8d8a4ea5
SP
1475 /* use_pack() assures us we have [base, base + 20) available
1476 * as a range that we can look at at. (Its actually the hash
3dff5379 1477 * size that is assured.) With our object header encoding
8d8a4ea5
SP
1478 * the maximum deflated object size is 2^137, which is just
1479 * insane, so we know won't exceed what we have been given.
1480 */
2b87c45b 1481 base = use_pack(p, w_curs, *curpos, &left);
09ded04b
NP
1482 used = unpack_object_header_buffer(base, left, &type, sizep);
1483 if (!used) {
1484 type = OBJ_BAD;
1485 } else
1486 *curpos += used;
ad1ed5ee 1487
2b87c45b 1488 return type;
a733cb60
LT
1489}
1490
21666f1a 1491const char *packed_object_info_detail(struct packed_git *p,
c4001d92 1492 off_t obj_offset,
21666f1a
NP
1493 unsigned long *size,
1494 unsigned long *store_size,
1495 unsigned int *delta_chain_length,
1496 unsigned char *base_sha1)
ad8c80a5 1497{
03e79c88 1498 struct pack_window *w_curs = NULL;
c4001d92
SP
1499 off_t curpos;
1500 unsigned long dummy;
43057304 1501 unsigned char *next_sha1;
21666f1a 1502 enum object_type type;
70f5d5d3 1503 struct revindex_entry *revidx;
ad8c80a5 1504
43057304 1505 *delta_chain_length = 0;
2b87c45b 1506 curpos = obj_offset;
21666f1a 1507 type = unpack_object_header(p, &w_curs, &curpos, size);
43057304 1508
70f5d5d3
NP
1509 revidx = find_pack_revindex(p, obj_offset);
1510 *store_size = revidx[1].offset - obj_offset;
1511
43057304 1512 for (;;) {
21666f1a 1513 switch (type) {
43057304 1514 default:
08a19d87 1515 die("pack %s contains unknown object type %d",
21666f1a 1516 p->pack_name, type);
43057304
NP
1517 case OBJ_COMMIT:
1518 case OBJ_TREE:
1519 case OBJ_BLOB:
1520 case OBJ_TAG:
03e79c88 1521 unuse_pack(&w_curs);
21666f1a 1522 return typename(type);
eb32d236 1523 case OBJ_OFS_DELTA:
21666f1a 1524 obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
8eca0b47
NP
1525 if (!obj_offset)
1526 die("pack %s contains bad delta base reference of type %s",
1527 p->pack_name, typename(type));
eb32d236 1528 if (*delta_chain_length == 0) {
70f5d5d3
NP
1529 revidx = find_pack_revindex(p, obj_offset);
1530 hashcpy(base_sha1, nth_packed_object_sha1(p, revidx->nr));
eb32d236
NP
1531 }
1532 break;
1533 case OBJ_REF_DELTA:
2b87c45b 1534 next_sha1 = use_pack(p, &w_curs, curpos, NULL);
43057304
NP
1535 if (*delta_chain_length == 0)
1536 hashcpy(base_sha1, next_sha1);
2b87c45b 1537 obj_offset = find_pack_entry_one(next_sha1, p);
43057304
NP
1538 break;
1539 }
43057304 1540 (*delta_chain_length)++;
2b87c45b 1541 curpos = obj_offset;
21666f1a 1542 type = unpack_object_header(p, &w_curs, &curpos, &dummy);
ad8c80a5 1543 }
ad8c80a5
JH
1544}
1545
c4001d92 1546static int packed_object_info(struct packed_git *p, off_t obj_offset,
21666f1a 1547 unsigned long *sizep)
1f688557 1548{
03e79c88 1549 struct pack_window *w_curs = NULL;
c4001d92
SP
1550 unsigned long size;
1551 off_t curpos = obj_offset;
21666f1a 1552 enum object_type type;
5db47c2b 1553
21666f1a 1554 type = unpack_object_header(p, &w_curs, &curpos, &size);
5db47c2b 1555
21666f1a 1556 switch (type) {
eb32d236
NP
1557 case OBJ_OFS_DELTA:
1558 case OBJ_REF_DELTA:
21666f1a
NP
1559 type = packed_delta_info(p, &w_curs, curpos,
1560 type, obj_offset, sizep);
2b87c45b 1561 break;
a733cb60 1562 case OBJ_COMMIT:
a733cb60 1563 case OBJ_TREE:
a733cb60 1564 case OBJ_BLOB:
a733cb60 1565 case OBJ_TAG:
2b87c45b
NP
1566 if (sizep)
1567 *sizep = size;
a69d0943 1568 break;
1f688557 1569 default:
3d77d877
NP
1570 error("unknown object type %i at offset %"PRIuMAX" in %s",
1571 type, (uintmax_t)obj_offset, p->pack_name);
1572 type = OBJ_BAD;
1f688557 1573 }
2b87c45b 1574 unuse_pack(&w_curs);
21666f1a 1575 return type;
1f688557
JH
1576}
1577
eb950c19 1578static void *unpack_compressed_entry(struct packed_git *p,
03e79c88 1579 struct pack_window **w_curs,
c4001d92 1580 off_t curpos,
eb950c19 1581 unsigned long size)
de530aaa
SP
1582{
1583 int st;
1584 z_stream stream;
079afb18 1585 unsigned char *buffer, *in;
de530aaa
SP
1586
1587 buffer = xmalloc(size + 1);
1588 buffer[size] = 0;
1589 memset(&stream, 0, sizeof(stream));
de530aaa
SP
1590 stream.next_out = buffer;
1591 stream.avail_out = size;
1592
39c68542 1593 git_inflate_init(&stream);
079afb18 1594 do {
2b87c45b 1595 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18 1596 stream.next_in = in;
39c68542 1597 st = git_inflate(&stream, Z_FINISH);
2b87c45b 1598 curpos += stream.next_in - in;
079afb18 1599 } while (st == Z_OK || st == Z_BUF_ERROR);
39c68542 1600 git_inflate_end(&stream);
de530aaa
SP
1601 if ((st != Z_STREAM_END) || stream.total_out != size) {
1602 free(buffer);
1603 return NULL;
1604 }
1605
1606 return buffer;
1607}
1608
e5e01619
LT
1609#define MAX_DELTA_CACHE (256)
1610
18bdec11 1611static size_t delta_base_cached;
5e08ecbf
NP
1612
1613static struct delta_base_cache_lru_list {
1614 struct delta_base_cache_lru_list *prev;
1615 struct delta_base_cache_lru_list *next;
1616} delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru };
1617
e5e01619 1618static struct delta_base_cache_entry {
5e08ecbf
NP
1619 struct delta_base_cache_lru_list lru;
1620 void *data;
e5e01619
LT
1621 struct packed_git *p;
1622 off_t base_offset;
1623 unsigned long size;
e5e01619
LT
1624 enum object_type type;
1625} delta_base_cache[MAX_DELTA_CACHE];
1626
1627static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
1628{
1629 unsigned long hash;
1630
1631 hash = (unsigned long)p + (unsigned long)base_offset;
1632 hash += (hash >> 8) + (hash >> 16);
3358004a 1633 return hash % MAX_DELTA_CACHE;
e5e01619
LT
1634}
1635
62f255ad 1636static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
a0cba108 1637 unsigned long *base_size, enum object_type *type, int keep_cache)
62f255ad 1638{
e5e01619
LT
1639 void *ret;
1640 unsigned long hash = pack_entry_hash(p, base_offset);
1641 struct delta_base_cache_entry *ent = delta_base_cache + hash;
1642
1643 ret = ent->data;
749bc58c
MV
1644 if (!ret || ent->p != p || ent->base_offset != base_offset)
1645 return unpack_entry(p, base_offset, type, base_size);
e5e01619 1646
18bdec11 1647 if (!keep_cache) {
a0cba108 1648 ent->data = NULL;
5e08ecbf
NP
1649 ent->lru.next->prev = ent->lru.prev;
1650 ent->lru.prev->next = ent->lru.next;
18bdec11 1651 delta_base_cached -= ent->size;
182af834
PH
1652 } else {
1653 ret = xmemdupz(ent->data, ent->size);
a0cba108 1654 }
e5e01619
LT
1655 *type = ent->type;
1656 *base_size = ent->size;
1657 return ret;
62f255ad
LT
1658}
1659
18bdec11
SP
1660static inline void release_delta_base_cache(struct delta_base_cache_entry *ent)
1661{
1662 if (ent->data) {
1663 free(ent->data);
1664 ent->data = NULL;
5e08ecbf
NP
1665 ent->lru.next->prev = ent->lru.prev;
1666 ent->lru.prev->next = ent->lru.next;
18bdec11
SP
1667 delta_base_cached -= ent->size;
1668 }
1669}
1670
3d20c636
SP
1671void clear_delta_base_cache(void)
1672{
1673 unsigned long p;
1674 for (p = 0; p < MAX_DELTA_CACHE; p++)
1675 release_delta_base_cache(&delta_base_cache[p]);
1676}
1677
62f255ad
LT
1678static void add_delta_base_cache(struct packed_git *p, off_t base_offset,
1679 void *base, unsigned long base_size, enum object_type type)
1680{
5e08ecbf 1681 unsigned long hash = pack_entry_hash(p, base_offset);
e5e01619 1682 struct delta_base_cache_entry *ent = delta_base_cache + hash;
5e08ecbf 1683 struct delta_base_cache_lru_list *lru;
e5e01619 1684
18bdec11
SP
1685 release_delta_base_cache(ent);
1686 delta_base_cached += base_size;
5e08ecbf
NP
1687
1688 for (lru = delta_base_cache_lru.next;
1689 delta_base_cached > delta_base_cache_limit
1690 && lru != &delta_base_cache_lru;
1691 lru = lru->next) {
1692 struct delta_base_cache_entry *f = (void *)lru;
18bdec11
SP
1693 if (f->type == OBJ_BLOB)
1694 release_delta_base_cache(f);
1695 }
5e08ecbf
NP
1696 for (lru = delta_base_cache_lru.next;
1697 delta_base_cached > delta_base_cache_limit
1698 && lru != &delta_base_cache_lru;
1699 lru = lru->next) {
1700 struct delta_base_cache_entry *f = (void *)lru;
1701 release_delta_base_cache(f);
1702 }
18bdec11 1703
e5e01619
LT
1704 ent->p = p;
1705 ent->base_offset = base_offset;
1706 ent->type = type;
1707 ent->data = base;
1708 ent->size = base_size;
5e08ecbf
NP
1709 ent->lru.next = &delta_base_cache_lru;
1710 ent->lru.prev = delta_base_cache_lru.prev;
1711 delta_base_cache_lru.prev->next = &ent->lru;
1712 delta_base_cache_lru.prev = &ent->lru;
62f255ad
LT
1713}
1714
c2c5b270
CC
1715static void *read_object(const unsigned char *sha1, enum object_type *type,
1716 unsigned long *size);
1717
eb950c19 1718static void *unpack_delta_entry(struct packed_git *p,
03e79c88 1719 struct pack_window **w_curs,
c4001d92 1720 off_t curpos,
1f688557 1721 unsigned long delta_size,
c4001d92 1722 off_t obj_offset,
21666f1a 1723 enum object_type *type,
eb950c19 1724 unsigned long *sizep)
1f688557 1725{
7c3e8be3 1726 void *delta_data, *result, *base;
c4001d92
SP
1727 unsigned long base_size;
1728 off_t base_offset;
43057304 1729
21666f1a 1730 base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
8eca0b47
NP
1731 if (!base_offset) {
1732 error("failed to validate delta base reference "
1733 "at offset %"PRIuMAX" from %s",
1734 (uintmax_t)curpos, p->pack_name);
1735 return NULL;
1736 }
eac12e2d 1737 unuse_pack(w_curs);
a0cba108 1738 base = cache_or_unpack_entry(p, base_offset, &base_size, type, 0);
8eca0b47
NP
1739 if (!base) {
1740 /*
1741 * We're probably in deep shit, but let's try to fetch
1742 * the required base anyway from another pack or loose.
1743 * This is costly but should happen only in the presence
1744 * of a corrupted pack, and is better than failing outright.
1745 */
08698b1e
NP
1746 struct revindex_entry *revidx;
1747 const unsigned char *base_sha1;
1748 revidx = find_pack_revindex(p, base_offset);
1749 if (!revidx)
1750 return NULL;
1751 base_sha1 = nth_packed_object_sha1(p, revidx->nr);
8eca0b47
NP
1752 error("failed to read delta base object %s"
1753 " at offset %"PRIuMAX" from %s",
1754 sha1_to_hex(base_sha1), (uintmax_t)base_offset,
1755 p->pack_name);
1756 mark_bad_packed_object(p, base_sha1);
ac939109 1757 base = read_object(base_sha1, type, &base_size);
8eca0b47
NP
1758 if (!base)
1759 return NULL;
1760 }
67686d95 1761
2b87c45b 1762 delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size);
8eca0b47
NP
1763 if (!delta_data) {
1764 error("failed to unpack compressed delta "
1765 "at offset %"PRIuMAX" from %s",
1766 (uintmax_t)curpos, p->pack_name);
1767 free(base);
1768 return NULL;
1769 }
1f688557
JH
1770 result = patch_delta(base, base_size,
1771 delta_data, delta_size,
21666f1a 1772 sizep);
1f688557
JH
1773 if (!result)
1774 die("failed to apply delta");
1775 free(delta_data);
62f255ad 1776 add_delta_base_cache(p, base_offset, base, base_size, *type);
1f688557
JH
1777 return result;
1778}
1779
0e8189e2
NP
1780int do_check_packed_object_crc;
1781
c4001d92 1782void *unpack_entry(struct packed_git *p, off_t obj_offset,
21666f1a 1783 enum object_type *type, unsigned long *sizep)
1f688557 1784{
03e79c88 1785 struct pack_window *w_curs = NULL;
c4001d92 1786 off_t curpos = obj_offset;
21666f1a 1787 void *data;
1f688557 1788
0e8189e2
NP
1789 if (do_check_packed_object_crc && p->index_version > 1) {
1790 struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
1791 unsigned long len = revidx[1].offset - obj_offset;
1792 if (check_pack_crc(p, &w_curs, obj_offset, len, revidx->nr)) {
1793 const unsigned char *sha1 =
1794 nth_packed_object_sha1(p, revidx->nr);
1795 error("bad packed object CRC for %s",
1796 sha1_to_hex(sha1));
1797 mark_bad_packed_object(p, sha1);
f755bb99 1798 unuse_pack(&w_curs);
0e8189e2
NP
1799 return NULL;
1800 }
1801 }
1802
21666f1a
NP
1803 *type = unpack_object_header(p, &w_curs, &curpos, sizep);
1804 switch (*type) {
eb32d236
NP
1805 case OBJ_OFS_DELTA:
1806 case OBJ_REF_DELTA:
21666f1a
NP
1807 data = unpack_delta_entry(p, &w_curs, curpos, *sizep,
1808 obj_offset, type, sizep);
4d703a1a 1809 break;
a733cb60 1810 case OBJ_COMMIT:
a733cb60 1811 case OBJ_TREE:
a733cb60 1812 case OBJ_BLOB:
a733cb60 1813 case OBJ_TAG:
21666f1a 1814 data = unpack_compressed_entry(p, &w_curs, curpos, *sizep);
4d703a1a 1815 break;
1f688557 1816 default:
8eca0b47
NP
1817 data = NULL;
1818 error("unknown object type %i at offset %"PRIuMAX" in %s",
1819 *type, (uintmax_t)obj_offset, p->pack_name);
1f688557 1820 }
03e79c88 1821 unuse_pack(&w_curs);
21666f1a 1822 return data;
1f688557
JH
1823}
1824
d079837e 1825const unsigned char *nth_packed_object_sha1(struct packed_git *p,
d72308e0 1826 uint32_t n)
9a217f2a 1827{
42873078 1828 const unsigned char *index = p->index_data;
d079837e
SP
1829 if (!index) {
1830 if (open_pack_index(p))
1831 return NULL;
1832 index = p->index_data;
1833 }
57059091 1834 if (n >= p->num_objects)
d72308e0 1835 return NULL;
74e34e1f
NP
1836 index += 4 * 256;
1837 if (p->index_version == 1) {
1838 return index + 24 * n + 4;
1839 } else {
1840 index += 8;
1841 return index + 20 * n;
1842 }
1843}
1844
99093238 1845off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
74e34e1f
NP
1846{
1847 const unsigned char *index = p->index_data;
1848 index += 4 * 256;
1849 if (p->index_version == 1) {
1850 return ntohl(*((uint32_t *)(index + 24 * n)));
1851 } else {
1852 uint32_t off;
1853 index += 8 + p->num_objects * (20 + 4);
1854 off = ntohl(*((uint32_t *)(index + 4 * n)));
1855 if (!(off & 0x80000000))
1856 return off;
1857 index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
1858 return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
1859 ntohl(*((uint32_t *)(index + 4)));
1860 }
9a217f2a
JH
1861}
1862
c4001d92 1863off_t find_pack_entry_one(const unsigned char *sha1,
43057304 1864 struct packed_git *p)
1f688557 1865{
42873078 1866 const uint32_t *level1_ofs = p->index_data;
42873078 1867 const unsigned char *index = p->index_data;
628522ec
JH
1868 unsigned hi, lo, stride;
1869 static int use_lookup = -1;
1870 static int debug_lookup = -1;
1871
1872 if (debug_lookup < 0)
1873 debug_lookup = !!getenv("GIT_DEBUG_LOOKUP");
42873078 1874
d079837e
SP
1875 if (!index) {
1876 if (open_pack_index(p))
1877 return 0;
1878 level1_ofs = p->index_data;
1879 index = p->index_data;
1880 }
74e34e1f
NP
1881 if (p->index_version > 1) {
1882 level1_ofs += 2;
1883 index += 8;
1884 }
42873078 1885 index += 4 * 256;
74e34e1f
NP
1886 hi = ntohl(level1_ofs[*sha1]);
1887 lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
628522ec
JH
1888 if (p->index_version > 1) {
1889 stride = 20;
1890 } else {
1891 stride = 24;
1892 index += 4;
1893 }
1894
1895 if (debug_lookup)
6e1c2344 1896 printf("%02x%02x%02x... lo %u hi %u nr %"PRIu32"\n",
628522ec
JH
1897 sha1[0], sha1[1], sha1[2], lo, hi, p->num_objects);
1898
1899 if (use_lookup < 0)
1900 use_lookup = !!getenv("GIT_USE_LOOKUP");
1901 if (use_lookup) {
1902 int pos = sha1_entry_pos(index, stride, 0,
1903 lo, hi, p->num_objects, sha1);
1904 if (pos < 0)
1905 return 0;
1906 return nth_packed_object_offset(p, pos);
1907 }
1f688557
JH
1908
1909 do {
74e34e1f 1910 unsigned mi = (lo + hi) / 2;
628522ec
JH
1911 int cmp = hashcmp(index + mi * stride, sha1);
1912
1913 if (debug_lookup)
1914 printf("lo %u hi %u rg %u mi %u\n",
1915 lo, hi, hi - lo, mi);
43057304 1916 if (!cmp)
74e34e1f 1917 return nth_packed_object_offset(p, mi);
1f688557
JH
1918 if (cmp > 0)
1919 hi = mi;
1920 else
1921 lo = mi+1;
1922 } while (lo < hi);
1923 return 0;
1924}
1925
4d6acb70 1926static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1f688557 1927{
f7c22cc6 1928 static struct packed_git *last_found = (void *)1;
1f688557 1929 struct packed_git *p;
c4001d92 1930 off_t offset;
43057304 1931
1f688557 1932 prepare_packed_git();
f7c22cc6
NP
1933 if (!packed_git)
1934 return 0;
1935 p = (last_found == (void *)1) ? packed_git : last_found;
1f688557 1936
f7c22cc6 1937 do {
8eca0b47
NP
1938 if (p->num_bad_objects) {
1939 unsigned i;
1940 for (i = 0; i < p->num_bad_objects; i++)
1941 if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
1942 goto next;
1943 }
1944
43057304
NP
1945 offset = find_pack_entry_one(sha1, p);
1946 if (offset) {
c715f783
SP
1947 /*
1948 * We are about to tell the caller where they can
1949 * locate the requested object. We better make
1950 * sure the packfile is still here and can be
1951 * accessed before supplying that answer, as
1952 * it may have been deleted since the index
1953 * was loaded!
1954 */
1955 if (p->pack_fd == -1 && open_packed_git(p)) {
1956 error("packfile %s cannot be accessed", p->pack_name);
f7c22cc6 1957 goto next;
c715f783 1958 }
43057304
NP
1959 e->offset = offset;
1960 e->p = p;
1961 hashcpy(e->sha1, sha1);
f7c22cc6 1962 last_found = p;
1f688557 1963 return 1;
43057304 1964 }
f7c22cc6
NP
1965
1966 next:
1967 if (p == last_found)
1968 p = packed_git;
1969 else
1970 p = p->next;
1971 if (p == last_found)
1972 p = p->next;
1973 } while (p);
1f688557
JH
1974 return 0;
1975}
1976
a6080a0a 1977struct packed_git *find_sha1_pack(const unsigned char *sha1,
bf592c50
DB
1978 struct packed_git *packs)
1979{
1980 struct packed_git *p;
bf592c50
DB
1981
1982 for (p = packs; p; p = p->next) {
43057304 1983 if (find_pack_entry_one(sha1, p))
bf592c50
DB
1984 return p;
1985 }
1986 return NULL;
21666f1a 1987
bf592c50
DB
1988}
1989
21666f1a 1990static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep)
65c2e0c3 1991{
36e4d74a 1992 int status;
65c2e0c3
JH
1993 unsigned long mapsize, size;
1994 void *map;
1995 z_stream stream;
d65a16f6 1996 char hdr[32];
65c2e0c3 1997
bb6b8e4f 1998 map = map_sha1_file(sha1, &mapsize);
f0df4ed5
JS
1999 if (!map)
2000 return error("unable to find %s", sha1_to_hex(sha1));
36e4d74a
JH
2001 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
2002 status = error("unable to unpack %s header",
2003 sha1_to_hex(sha1));
21666f1a 2004 else if ((status = parse_sha1_header(hdr, &size)) < 0)
36e4d74a 2005 status = error("unable to parse %s header", sha1_to_hex(sha1));
21666f1a
NP
2006 else if (sizep)
2007 *sizep = size;
39c68542 2008 git_inflate_end(&stream);
65c2e0c3
JH
2009 munmap(map, mapsize);
2010 return status;
2011}
2012
21666f1a 2013int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
f0df4ed5 2014{
f0df4ed5 2015 struct pack_entry e;
ddd63e64 2016 int status;
f0df4ed5 2017
cd673c1f 2018 if (!find_pack_entry(sha1, &e)) {
ddd63e64
SG
2019 /* Most likely it's a loose object. */
2020 status = sha1_loose_object_info(sha1, sizep);
2021 if (status >= 0)
2022 return status;
2023
2024 /* Not a loose object; someone else may have just packed it. */
f0df4ed5 2025 reprepare_packed_git();
cd673c1f 2026 if (!find_pack_entry(sha1, &e))
ddd63e64 2027 return status;
f0df4ed5 2028 }
3d77d877
NP
2029
2030 status = packed_object_info(e.p, e.offset, sizep);
2031 if (status < 0) {
2032 mark_bad_packed_object(e.p, sha1);
2033 status = sha1_object_info(sha1, sizep);
2034 }
2035
2036 return status;
f0df4ed5
JS
2037}
2038
21666f1a
NP
2039static void *read_packed_sha1(const unsigned char *sha1,
2040 enum object_type *type, unsigned long *size)
1f688557
JH
2041{
2042 struct pack_entry e;
8eca0b47 2043 void *data;
1f688557 2044
cd673c1f 2045 if (!find_pack_entry(sha1, &e))
1f688557 2046 return NULL;
8eca0b47
NP
2047 data = cache_or_unpack_entry(e.p, e.offset, size, type, 1);
2048 if (!data) {
2049 /*
2050 * We're probably in deep shit, but let's try to fetch
2051 * the required object anyway from another pack or loose.
2052 * This should happen only in the presence of a corrupted
2053 * pack, and is better than failing outright.
2054 */
2055 error("failed to read object %s at offset %"PRIuMAX" from %s",
2056 sha1_to_hex(sha1), (uintmax_t)e.offset, e.p->pack_name);
2057 mark_bad_packed_object(e.p, sha1);
ac939109 2058 data = read_object(sha1, type, size);
8eca0b47
NP
2059 }
2060 return data;
1f688557
JH
2061}
2062
d66b37bb
JH
2063/*
2064 * This is meant to hold a *small* number of objects that you would
2065 * want read_sha1_file() to be able to return, but yet you do not want
2066 * to write them into the object store (e.g. a browse-only
2067 * application).
2068 */
2069static struct cached_object {
2070 unsigned char sha1[20];
21666f1a 2071 enum object_type type;
d66b37bb
JH
2072 void *buf;
2073 unsigned long size;
2074} *cached_objects;
2075static int cached_object_nr, cached_object_alloc;
2076
346245a1 2077static struct cached_object empty_tree = {
14d9c578 2078 EMPTY_TREE_SHA1_BIN,
346245a1
JK
2079 OBJ_TREE,
2080 "",
2081 0
2082};
2083
d66b37bb
JH
2084static struct cached_object *find_cached_object(const unsigned char *sha1)
2085{
2086 int i;
2087 struct cached_object *co = cached_objects;
2088
2089 for (i = 0; i < cached_object_nr; i++, co++) {
2090 if (!hashcmp(co->sha1, sha1))
2091 return co;
2092 }
346245a1
JK
2093 if (!hashcmp(sha1, empty_tree.sha1))
2094 return &empty_tree;
d66b37bb
JH
2095 return NULL;
2096}
2097
21666f1a
NP
2098int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
2099 unsigned char *sha1)
d66b37bb
JH
2100{
2101 struct cached_object *co;
2102
21666f1a 2103 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
2104 if (has_sha1_file(sha1) || find_cached_object(sha1))
2105 return 0;
2106 if (cached_object_alloc <= cached_object_nr) {
2107 cached_object_alloc = alloc_nr(cached_object_alloc);
2108 cached_objects = xrealloc(cached_objects,
2109 sizeof(*cached_objects) *
2110 cached_object_alloc);
2111 }
2112 co = &cached_objects[cached_object_nr++];
2113 co->size = len;
21666f1a 2114 co->type = type;
efa13f7b
JH
2115 co->buf = xmalloc(len);
2116 memcpy(co->buf, buf, len);
d66b37bb
JH
2117 hashcpy(co->sha1, sha1);
2118 return 0;
2119}
2120
c2c5b270
CC
2121static void *read_object(const unsigned char *sha1, enum object_type *type,
2122 unsigned long *size)
0fcfd160
LT
2123{
2124 unsigned long mapsize;
2125 void *map, *buf;
d66b37bb
JH
2126 struct cached_object *co;
2127
2128 co = find_cached_object(sha1);
2129 if (co) {
21666f1a 2130 *type = co->type;
d66b37bb 2131 *size = co->size;
182af834 2132 return xmemdupz(co->buf, co->size);
d66b37bb 2133 }
0fcfd160 2134
8276c007
PE
2135 buf = read_packed_sha1(sha1, type, size);
2136 if (buf)
2137 return buf;
bb6b8e4f 2138 map = map_sha1_file(sha1, &mapsize);
0fcfd160 2139 if (map) {
7efbff75 2140 buf = unpack_sha1_file(map, mapsize, type, size, sha1);
0fcfd160
LT
2141 munmap(map, mapsize);
2142 return buf;
2143 }
637cdd9d 2144 reprepare_packed_git();
8276c007 2145 return read_packed_sha1(sha1, type, size);
0fcfd160
LT
2146}
2147
ac939109
NP
2148void *read_sha1_file(const unsigned char *sha1, enum object_type *type,
2149 unsigned long *size)
2150{
68095570
CC
2151 const unsigned char *repl = lookup_replace_object(sha1);
2152 void *data = read_object(repl, type, size);
2153
2154 /* die if we replaced an object with one that does not exist */
2155 if (!data && repl != sha1)
2156 die("replacement %s not found for %s",
2157 sha1_to_hex(repl), sha1_to_hex(sha1));
2158
ac939109 2159 /* legacy behavior is to die on corrupted objects */
68095570
CC
2160 if (!data && (has_loose_object(repl) || has_packed_and_bad(repl)))
2161 die("object %s is corrupted", sha1_to_hex(repl));
2162
ac939109
NP
2163 return data;
2164}
2165
40469ee9 2166void *read_object_with_reference(const unsigned char *sha1,
21666f1a 2167 const char *required_type_name,
40469ee9
JH
2168 unsigned long *size,
2169 unsigned char *actual_sha1_return)
f4913f91 2170{
21666f1a 2171 enum object_type type, required_type;
f4913f91
JH
2172 void *buffer;
2173 unsigned long isize;
40469ee9 2174 unsigned char actual_sha1[20];
f4913f91 2175
21666f1a 2176 required_type = type_from_string(required_type_name);
e702496e 2177 hashcpy(actual_sha1, sha1);
40469ee9
JH
2178 while (1) {
2179 int ref_length = -1;
2180 const char *ref_type = NULL;
f4913f91 2181
21666f1a 2182 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
2183 if (!buffer)
2184 return NULL;
21666f1a 2185 if (type == required_type) {
40469ee9
JH
2186 *size = isize;
2187 if (actual_sha1_return)
e702496e 2188 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
2189 return buffer;
2190 }
2191 /* Handle references */
21666f1a 2192 else if (type == OBJ_COMMIT)
40469ee9 2193 ref_type = "tree ";
21666f1a 2194 else if (type == OBJ_TAG)
40469ee9
JH
2195 ref_type = "object ";
2196 else {
2197 free(buffer);
2198 return NULL;
2199 }
2200 ref_length = strlen(ref_type);
f4913f91 2201
50974ec9
MK
2202 if (ref_length + 40 > isize ||
2203 memcmp(buffer, ref_type, ref_length) ||
1d7f171c 2204 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
2205 free(buffer);
2206 return NULL;
2207 }
1cf58e72 2208 free(buffer);
40469ee9
JH
2209 /* Now we have the ID of the referred-to object in
2210 * actual_sha1. Check again. */
f4913f91 2211 }
f4913f91
JH
2212}
2213
ce9fbf16 2214static void write_sha1_file_prepare(const void *buf, unsigned long len,
972a9155 2215 const char *type, unsigned char *sha1,
d65a16f6 2216 char *hdr, int *hdrlen)
d410c0f5 2217{
9126f009 2218 git_SHA_CTX c;
d410c0f5
JH
2219
2220 /* Generate the header */
d65a16f6 2221 *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
d410c0f5
JH
2222
2223 /* Sha1.. */
9126f009
NP
2224 git_SHA1_Init(&c);
2225 git_SHA1_Update(&c, hdr, *hdrlen);
2226 git_SHA1_Update(&c, buf, len);
2227 git_SHA1_Final(sha1, &c);
d410c0f5
JH
2228}
2229
230f1322 2230/*
5a688fe4
JH
2231 * Move the just written object into its final resting place.
2232 * NEEDSWORK: this should be renamed to finalize_temp_file() as
2233 * "moving" is only a part of what it does, when no patch between
2234 * master to pu changes the call sites of this function.
230f1322 2235 */
839837b9 2236int move_temp_to_file(const char *tmpfile, const char *filename)
230f1322 2237{
e32c0a9c 2238 int ret = 0;
5a688fe4 2239
348df166 2240 if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
be66a6c4
JS
2241 goto try_rename;
2242 else if (link(tmpfile, filename))
e32c0a9c 2243 ret = errno;
7ebb6fca
LT
2244
2245 /*
2246 * Coda hack - coda doesn't like cross-directory links,
2247 * so we fall back to a rename, which will mean that it
2248 * won't be able to check collisions, but that's not a
2249 * big deal.
2250 *
2251 * The same holds for FAT formatted media.
2252 *
3be1f18e 2253 * When this succeeds, we just return. We have nothing
7ebb6fca
LT
2254 * left to unlink.
2255 */
2256 if (ret && ret != EEXIST) {
be66a6c4 2257 try_rename:
7ebb6fca 2258 if (!rename(tmpfile, filename))
3be1f18e 2259 goto out;
9e48b389 2260 ret = errno;
230f1322 2261 }
691f1a28 2262 unlink_or_warn(tmpfile);
230f1322
LT
2263 if (ret) {
2264 if (ret != EEXIST) {
916d081b 2265 return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret));
230f1322
LT
2266 }
2267 /* FIXME!!! Collision check here ? */
2268 }
2269
3be1f18e 2270out:
17e61b82 2271 if (set_shared_perm(filename, (S_IFREG|0444)))
5a688fe4 2272 return error("unable to set permission to '%s'", filename);
230f1322
LT
2273 return 0;
2274}
2275
4d548150
LT
2276static int write_buffer(int fd, const void *buf, size_t len)
2277{
d34cf19b 2278 if (write_in_full(fd, buf, len) < 0)
93822c22 2279 return error("file write error (%s)", strerror(errno));
4d548150
LT
2280 return 0;
2281}
2282
ce9fbf16 2283int hash_sha1_file(const void *buf, unsigned long len, const char *type,
abdc3fc8
RS
2284 unsigned char *sha1)
2285{
d65a16f6 2286 char hdr[32];
abdc3fc8
RS
2287 int hdrlen;
2288 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2289 return 0;
2290}
2291
e9039dd3
LT
2292/* Finalize a file on disk, and close it. */
2293static void close_sha1_file(int fd)
2294{
aafe9fba
LT
2295 if (fsync_object_files)
2296 fsync_or_die(fd, "sha1 file");
e9039dd3 2297 if (close(fd) != 0)
e8bd78c3 2298 die("error when closing sha1 file (%s)", strerror(errno));
e9039dd3
LT
2299}
2300
5723fe7e
LT
2301/* Size of directory component, including the ending '/' */
2302static inline int directory_size(const char *filename)
2303{
2304 const char *s = strrchr(filename, '/');
2305 if (!s)
2306 return 0;
2307 return s - filename + 1;
2308}
2309
2310/*
2311 * This creates a temporary file in the same directory as the final
2312 * 'filename'
2313 *
2314 * We want to avoid cross-directory filename renames, because those
2315 * can have problems on various filesystems (FAT, NFS, Coda).
2316 */
2317static int create_tmpfile(char *buffer, size_t bufsiz, const char *filename)
2318{
2319 int fd, dirlen = directory_size(filename);
2320
2321 if (dirlen + 20 > bufsiz) {
2322 errno = ENAMETOOLONG;
2323 return -1;
2324 }
2325 memcpy(buffer, filename, dirlen);
2326 strcpy(buffer + dirlen, "tmp_obj_XXXXXX");
2327 fd = mkstemp(buffer);
cbacbf4e 2328 if (fd < 0 && dirlen && errno == ENOENT) {
5723fe7e 2329 /* Make sure the directory exists */
6ff6af62 2330 memcpy(buffer, filename, dirlen);
5723fe7e 2331 buffer[dirlen-1] = 0;
3bfaf018 2332 if (mkdir(buffer, 0777) || adjust_shared_perm(buffer))
5723fe7e
LT
2333 return -1;
2334
2335 /* Try again */
2336 strcpy(buffer + dirlen - 1, "/tmp_obj_XXXXXX");
2337 fd = mkstemp(buffer);
2338 }
2339 return fd;
2340}
2341
bbac7311
NP
2342static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
2343 void *buf, unsigned long len, time_t mtime)
0fcfd160 2344{
915308b1
JK
2345 int fd, ret;
2346 size_t size;
bf0f910d 2347 unsigned char *compressed;
0fcfd160 2348 z_stream stream;
706bc531 2349 char *filename;
aac17941 2350 static char tmpfile[PATH_MAX];
a44c9a5e 2351
972a9155 2352 filename = sha1_file_name(sha1);
5723fe7e 2353 fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename);
fd73ccf2
JS
2354 while (fd < 0 && errno == EMFILE && unuse_one_window(packed_git, -1))
2355 fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename);
aac17941 2356 if (fd < 0) {
35243577 2357 if (errno == EACCES)
916d081b
PB
2358 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
2359 else
2360 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
aac17941
LT
2361 }
2362
0fcfd160
LT
2363 /* Set it up */
2364 memset(&stream, 0, sizeof(stream));
12f6c308 2365 deflateInit(&stream, zlib_compression_level);
93821bd9 2366 size = 8 + deflateBound(&stream, len+hdrlen);
812666c8 2367 compressed = xmalloc(size);
0fcfd160
LT
2368
2369 /* Compress it */
0fcfd160
LT
2370 stream.next_out = compressed;
2371 stream.avail_out = size;
a44c9a5e
LT
2372
2373 /* First header.. */
d65a16f6 2374 stream.next_in = (unsigned char *)hdr;
a44c9a5e 2375 stream.avail_in = hdrlen;
726f852b
NP
2376 while (deflate(&stream, 0) == Z_OK)
2377 /* nothing */;
a44c9a5e
LT
2378
2379 /* Then the data itself.. */
2380 stream.next_in = buf;
2381 stream.avail_in = len;
ac54c277
LT
2382 ret = deflate(&stream, Z_FINISH);
2383 if (ret != Z_STREAM_END)
2384 die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
2385
2386 ret = deflateEnd(&stream);
2387 if (ret != Z_OK)
2388 die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
2389
0fcfd160
LT
2390 size = stream.total_out;
2391
4d548150
LT
2392 if (write_buffer(fd, compressed, size) < 0)
2393 die("unable to write sha1 file");
e9039dd3 2394 close_sha1_file(fd);
383f85b7 2395 free(compressed);
0fcfd160 2396
bbac7311
NP
2397 if (mtime) {
2398 struct utimbuf utb;
2399 utb.actime = mtime;
2400 utb.modtime = mtime;
2401 if (utime(tmpfile, &utb) < 0)
2402 warning("failed utime() on %s: %s",
2403 tmpfile, strerror(errno));
2404 }
2405
230f1322 2406 return move_temp_to_file(tmpfile, filename);
0fcfd160 2407}
8237b185 2408
bbac7311
NP
2409int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
2410{
2411 unsigned char sha1[20];
2412 char hdr[32];
2413 int hdrlen;
2414
2415 /* Normally if we have it in the pack then we do not bother writing
2416 * it out into .git/objects/??/?{38} file.
2417 */
2418 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
2419 if (returnsha1)
2420 hashcpy(returnsha1, sha1);
2421 if (has_sha1_file(sha1))
2422 return 0;
2423 return write_loose_object(sha1, hdr, hdrlen, buf, len, 0);
2424}
2425
2426int force_object_loose(const unsigned char *sha1, time_t mtime)
2427{
bbac7311
NP
2428 void *buf;
2429 unsigned long len;
2430 enum object_type type;
2431 char hdr[32];
2432 int hdrlen;
1fb23e65 2433 int ret;
bbac7311 2434
c529d75a 2435 if (has_loose_object(sha1))
bbac7311
NP
2436 return 0;
2437 buf = read_packed_sha1(sha1, &type, &len);
2438 if (!buf)
2439 return error("cannot read sha1_file for %s", sha1_to_hex(sha1));
2440 hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
1fb23e65
BS
2441 ret = write_loose_object(sha1, hdr, hdrlen, buf, len, mtime);
2442 free(buf);
2443
2444 return ret;
bbac7311
NP
2445}
2446
bf592c50
DB
2447int has_pack_index(const unsigned char *sha1)
2448{
2449 struct stat st;
2450 if (stat(sha1_pack_index_name(sha1), &st))
2451 return 0;
2452 return 1;
2453}
2454
2455int has_pack_file(const unsigned char *sha1)
2456{
2457 struct stat st;
2458 if (stat(sha1_pack_name(sha1), &st))
2459 return 0;
2460 return 1;
2461}
2462
cd673c1f
JH
2463int has_sha1_pack(const unsigned char *sha1)
2464{
2465 struct pack_entry e;
2466 return find_pack_entry(sha1, &e);
2467}
2468
8237b185
DB
2469int has_sha1_file(const unsigned char *sha1)
2470{
1f688557
JH
2471 struct pack_entry e;
2472
cd673c1f 2473 if (find_pack_entry(sha1, &e))
1f688557 2474 return 1;
c529d75a 2475 return has_loose_object(sha1);
8237b185 2476}
74400e71 2477
43df4f86
DP
2478static int index_mem(unsigned char *sha1, void *buf, size_t size,
2479 int write_object, enum object_type type, const char *path)
e7332f96 2480{
6c510bee 2481 int ret, re_allocated = 0;
74400e71 2482
7672db20 2483 if (!type)
edaec3fb 2484 type = OBJ_BLOB;
6c510bee
LT
2485
2486 /*
2487 * Convert blobs to git internal format
2488 */
43df4f86 2489 if ((type == OBJ_BLOB) && path) {
f285a2d7 2490 struct strbuf nbuf = STRBUF_INIT;
21e5ad50
SP
2491 if (convert_to_git(path, buf, size, &nbuf,
2492 write_object ? safe_crlf : 0)) {
b315c5c0 2493 buf = strbuf_detach(&nbuf, &size);
6c510bee
LT
2494 re_allocated = 1;
2495 }
2496 }
2497
7672db20 2498 if (write_object)
edaec3fb 2499 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 2500 else
edaec3fb 2501 ret = hash_sha1_file(buf, size, typename(type), sha1);
43df4f86 2502 if (re_allocated)
6c510bee 2503 free(buf);
43df4f86
DP
2504 return ret;
2505}
2506
2507int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object,
2508 enum object_type type, const char *path)
2509{
2510 int ret;
2511 size_t size = xsize_t(st->st_size);
2512
2513 if (!S_ISREG(st->st_mode)) {
f285a2d7 2514 struct strbuf sbuf = STRBUF_INIT;
43df4f86
DP
2515 if (strbuf_read(&sbuf, fd, 4096) >= 0)
2516 ret = index_mem(sha1, sbuf.buf, sbuf.len, write_object,
2517 type, path);
2518 else
2519 ret = -1;
2520 strbuf_release(&sbuf);
2521 } else if (size) {
2522 void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
2523 ret = index_mem(sha1, buf, size, write_object, type, path);
aac17941 2524 munmap(buf, size);
43df4f86
DP
2525 } else
2526 ret = index_mem(sha1, NULL, size, write_object, type, path);
2527 close(fd);
aac17941 2528 return ret;
74400e71 2529}
ec1fcc16
JH
2530
2531int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
2532{
2533 int fd;
b760d3aa 2534 struct strbuf sb = STRBUF_INIT;
ec1fcc16
JH
2535
2536 switch (st->st_mode & S_IFMT) {
2537 case S_IFREG:
2538 fd = open(path, O_RDONLY);
2539 if (fd < 0)
2540 return error("open(\"%s\"): %s", path,
2541 strerror(errno));
53bca91a 2542 if (index_fd(sha1, fd, st, write_object, OBJ_BLOB, path) < 0)
ec1fcc16
JH
2543 return error("%s: failed to insert into database",
2544 path);
2545 break;
2546 case S_IFLNK:
b760d3aa 2547 if (strbuf_readlink(&sb, path, st->st_size)) {
ec1fcc16 2548 char *errstr = strerror(errno);
ec1fcc16
JH
2549 return error("readlink(\"%s\"): %s", path,
2550 errstr);
2551 }
abdc3fc8 2552 if (!write_object)
b760d3aa
LT
2553 hash_sha1_file(sb.buf, sb.len, blob_type, sha1);
2554 else if (write_sha1_file(sb.buf, sb.len, blob_type, sha1))
ec1fcc16
JH
2555 return error("%s: failed to insert into database",
2556 path);
b760d3aa 2557 strbuf_release(&sb);
ec1fcc16 2558 break;
f35a6d3b
LT
2559 case S_IFDIR:
2560 return resolve_gitlink_ref(path, "HEAD", sha1);
ec1fcc16
JH
2561 default:
2562 return error("%s: unsupported file type", path);
2563 }
2564 return 0;
2565}
a69e5429
JH
2566
2567int read_pack_header(int fd, struct pack_header *header)
2568{
c697ad14
HO
2569 if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header))
2570 /* "eof before pack header was fully read" */
2571 return PH_ERROR_EOF;
2572
a69e5429
JH
2573 if (header->hdr_signature != htonl(PACK_SIGNATURE))
2574 /* "protocol error (pack signature mismatch detected)" */
2575 return PH_ERROR_PACK_SIGNATURE;
2576 if (!pack_version_ok(header->hdr_version))
2577 /* "protocol error (pack version unsupported)" */
2578 return PH_ERROR_PROTOCOL;
2579 return 0;
2580}