cvsserver: avoid warning about active db handles
[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"
0fcfd160 16
144bde78
LT
17#ifndef O_NOATIME
18#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
19#define O_NOATIME 01000000
20#else
21#define O_NOATIME 0
22#endif
23#endif
24
88cd621d
JH
25const unsigned char null_sha1[20] = { 0, };
26
144bde78
LT
27static unsigned int sha1_file_open_flag = O_NOATIME;
28
0fcfd160
LT
29static unsigned hexval(char c)
30{
31 if (c >= '0' && c <= '9')
32 return c - '0';
33 if (c >= 'a' && c <= 'f')
34 return c - 'a' + 10;
35 if (c >= 'A' && c <= 'F')
36 return c - 'A' + 10;
37 return ~0;
38}
39
40int get_sha1_hex(const char *hex, unsigned char *sha1)
41{
42 int i;
43 for (i = 0; i < 20; i++) {
44 unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
45 if (val & ~0xff)
46 return -1;
47 *sha1++ = val;
48 hex += 2;
49 }
50 return 0;
51}
52
b2cb9425
JH
53int safe_create_leading_directories(char *path)
54{
55 char *pos = path;
67d42212
JR
56 struct stat st;
57
67ffdf4c
JS
58 if (*pos == '/')
59 pos++;
b2cb9425
JH
60
61 while (pos) {
62 pos = strchr(pos, '/');
63 if (!pos)
64 break;
65 *pos = 0;
67d42212
JR
66 if (!stat(path, &st)) {
67 /* path exists */
68 if (!S_ISDIR(st.st_mode)) {
b2cb9425 69 *pos = '/';
67d42212 70 return -3;
b2cb9425 71 }
457f06d6 72 }
67d42212
JR
73 else if (mkdir(path, 0777)) {
74 *pos = '/';
75 return -1;
76 }
457f06d6
JS
77 else if (adjust_shared_perm(path)) {
78 *pos = '/';
79 return -2;
80 }
b2cb9425
JH
81 *pos++ = '/';
82 }
83 return 0;
84}
723c31fe 85
0fcfd160
LT
86char * sha1_to_hex(const unsigned char *sha1)
87{
dcb3450f
LT
88 static int bufno;
89 static char hexbuffer[4][50];
0fcfd160 90 static const char hex[] = "0123456789abcdef";
dcb3450f 91 char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
0fcfd160
LT
92 int i;
93
94 for (i = 0; i < 20; i++) {
95 unsigned int val = *sha1++;
96 *buf++ = hex[val >> 4];
97 *buf++ = hex[val & 0xf];
98 }
1e80e044
JS
99 *buf = '\0';
100
0fcfd160
LT
101 return buffer;
102}
103
ace1534d
JH
104static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
105{
106 int i;
107 for (i = 0; i < 20; i++) {
108 static char hex[] = "0123456789abcdef";
109 unsigned int val = sha1[i];
110 char *pos = pathbuf + i*2 + (i > 0);
111 *pos++ = hex[val >> 4];
112 *pos = hex[val & 0xf];
113 }
114}
115
0fcfd160
LT
116/*
117 * NOTE! This returns a statically allocated buffer, so you have to be
118 * careful about using it. Do a "strdup()" if you need to save the
119 * filename.
ace1534d
JH
120 *
121 * Also note that this returns the location for creating. Reading
122 * SHA1 file can happen from any alternate directory listed in the
d19938ab 123 * DB_ENVIRONMENT environment variable if it is not found in
ace1534d 124 * the primary object database.
0fcfd160
LT
125 */
126char *sha1_file_name(const unsigned char *sha1)
127{
0fcfd160
LT
128 static char *name, *base;
129
130 if (!base) {
d19938ab 131 const char *sha1_file_directory = get_object_directory();
0fcfd160 132 int len = strlen(sha1_file_directory);
812666c8 133 base = xmalloc(len + 60);
0fcfd160
LT
134 memcpy(base, sha1_file_directory, len);
135 memset(base+len, 0, 60);
136 base[len] = '/';
137 base[len+3] = '/';
138 name = base + len + 1;
139 }
ace1534d 140 fill_sha1_path(name, sha1);
0fcfd160
LT
141 return base;
142}
143
bf592c50
DB
144char *sha1_pack_name(const unsigned char *sha1)
145{
146 static const char hex[] = "0123456789abcdef";
147 static char *name, *base, *buf;
148 int i;
149
150 if (!base) {
151 const char *sha1_file_directory = get_object_directory();
152 int len = strlen(sha1_file_directory);
153 base = xmalloc(len + 60);
154 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
155 name = base + len + 11;
156 }
157
158 buf = name;
159
160 for (i = 0; i < 20; i++) {
161 unsigned int val = *sha1++;
162 *buf++ = hex[val >> 4];
163 *buf++ = hex[val & 0xf];
164 }
165
166 return base;
167}
168
169char *sha1_pack_index_name(const unsigned char *sha1)
170{
171 static const char hex[] = "0123456789abcdef";
172 static char *name, *base, *buf;
173 int i;
174
175 if (!base) {
176 const char *sha1_file_directory = get_object_directory();
177 int len = strlen(sha1_file_directory);
178 base = xmalloc(len + 60);
179 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
180 name = base + len + 11;
181 }
182
183 buf = name;
184
185 for (i = 0; i < 20; i++) {
186 unsigned int val = *sha1++;
187 *buf++ = hex[val >> 4];
188 *buf++ = hex[val & 0xf];
189 }
190
191 return base;
192}
193
d5a63b99
JH
194struct alternate_object_database *alt_odb_list;
195static struct alternate_object_database **alt_odb_tail;
ace1534d 196
c2f493a4
MW
197static void read_info_alternates(const char * alternates, int depth);
198
ddd5d056
JH
199/*
200 * Prepare alternate object database registry.
d5a63b99
JH
201 *
202 * The variable alt_odb_list points at the list of struct
203 * alternate_object_database. The elements on this list come from
204 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
205 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
206 * whose contents is similar to that environment variable but can be
207 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
208 * contains "/the/directory/corresponding/to/.git/objects/...", while
209 * its name points just after the slash at the end of ".git/objects/"
210 * in the example above, and has enough space to hold 40-byte hex
211 * SHA1, an extra slash for the first level indirection, and the
212 * terminating NUL.
ddd5d056 213 */
c2f493a4 214static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
ace1534d 215{
c2f493a4 216 struct stat st;
1494e038 217 const char *objdir = get_object_directory();
c2f493a4
MW
218 struct alternate_object_database *ent;
219 struct alternate_object_database *alt;
220 /* 43 = 40-byte + 2 '/' + terminating NUL */
221 int pfxlen = len;
222 int entlen = pfxlen + 43;
ccfd3e99 223 int base_len = -1;
d5a63b99 224
c2f493a4
MW
225 if (*entry != '/' && relative_base) {
226 /* Relative alt-odb */
227 if (base_len < 0)
228 base_len = strlen(relative_base) + 1;
229 entlen += base_len;
230 pfxlen += base_len;
231 }
232 ent = xmalloc(sizeof(*ent) + entlen);
233
234 if (*entry != '/' && relative_base) {
235 memcpy(ent->base, relative_base, base_len - 1);
236 ent->base[base_len - 1] = '/';
237 memcpy(ent->base + base_len, entry, len);
238 }
239 else
240 memcpy(ent->base, entry, pfxlen);
241
242 ent->name = ent->base + pfxlen + 1;
243 ent->base[pfxlen + 3] = '/';
244 ent->base[pfxlen] = ent->base[entlen-1] = 0;
245
246 /* Detect cases where alternate disappeared */
247 if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
248 error("object directory %s does not exist; "
249 "check .git/objects/info/alternates.",
250 ent->base);
251 free(ent);
252 return -1;
253 }
254
255 /* Prevent the common mistake of listing the same
256 * thing twice, or object directory itself.
257 */
258 for (alt = alt_odb_list; alt; alt = alt->next) {
259 if (!memcmp(ent->base, alt->base, pfxlen)) {
260 free(ent);
261 return -1;
262 }
263 }
264 if (!memcmp(ent->base, objdir, pfxlen)) {
265 free(ent);
266 return -1;
267 }
268
269 /* add the alternate entry */
270 *alt_odb_tail = ent;
271 alt_odb_tail = &(ent->next);
272 ent->next = NULL;
273
274 /* recursively add alternates */
275 read_info_alternates(ent->base, depth + 1);
276
277 ent->base[pfxlen] = '/';
278
279 return 0;
280}
281
282static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
283 const char *relative_base, int depth)
284{
285 const char *cp, *last;
286
287 if (depth > 5) {
288 error("%s: ignoring alternate object stores, nesting too deep.",
289 relative_base);
290 return;
291 }
292
d5a63b99 293 last = alt;
9577e7e3
JH
294 while (last < ep) {
295 cp = last;
296 if (cp < ep && *cp == '#') {
297 while (cp < ep && *cp != sep)
298 cp++;
299 last = cp + 1;
300 continue;
301 }
c2f493a4
MW
302 while (cp < ep && *cp != sep)
303 cp++;
d5a63b99 304 if (last != cp) {
c2f493a4
MW
305 if ((*last != '/') && depth) {
306 error("%s: ignoring relative alternate object store %s",
307 relative_base, last);
308 } else {
309 link_alt_odb_entry(last, cp - last,
310 relative_base, depth);
1494e038 311 }
d5a63b99 312 }
9577e7e3 313 while (cp < ep && *cp == sep)
d5a63b99
JH
314 cp++;
315 last = cp;
9577e7e3 316 }
d5a63b99
JH
317}
318
c2f493a4 319static void read_info_alternates(const char * relative_base, int depth)
d5a63b99 320{
9577e7e3 321 char *map;
d5a63b99 322 struct stat st;
c2f493a4
MW
323 char path[PATH_MAX];
324 int fd;
d5a63b99 325
c2f493a4 326 sprintf(path, "%s/info/alternates", relative_base);
d5a63b99
JH
327 fd = open(path, O_RDONLY);
328 if (fd < 0)
329 return;
330 if (fstat(fd, &st) || (st.st_size == 0)) {
331 close(fd);
9a217f2a 332 return;
ace1534d 333 }
d5a63b99
JH
334 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
335 close(fd);
336 if (map == MAP_FAILED)
337 return;
338
c2f493a4
MW
339 link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth);
340
d5a63b99 341 munmap(map, st.st_size);
ace1534d
JH
342}
343
c2f493a4
MW
344void prepare_alt_odb(void)
345{
554fe20d 346 const char *alt;
c2f493a4
MW
347
348 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
349 if (!alt) alt = "";
350
351 if (alt_odb_tail)
352 return;
353 alt_odb_tail = &alt_odb_list;
354 link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL, 0);
355
356 read_info_alternates(get_object_directory(), 0);
357}
358
ace1534d
JH
359static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
360{
ace1534d 361 char *name = sha1_file_name(sha1);
d5a63b99 362 struct alternate_object_database *alt;
ace1534d
JH
363
364 if (!stat(name, st))
365 return name;
9a217f2a 366 prepare_alt_odb();
d5a63b99
JH
367 for (alt = alt_odb_list; alt; alt = alt->next) {
368 name = alt->name;
ace1534d 369 fill_sha1_path(name, sha1);
d5a63b99
JH
370 if (!stat(alt->base, st))
371 return alt->base;
ace1534d
JH
372 }
373 return NULL;
374}
375
1f688557
JH
376#define PACK_MAX_SZ (1<<26)
377static int pack_used_ctr;
378static unsigned long pack_mapped;
9a217f2a 379struct packed_git *packed_git;
1f688557 380
1f688557
JH
381static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
382 void **idx_map_)
383{
384 void *idx_map;
385 unsigned int *index;
386 unsigned long idx_size;
387 int nr, i;
e93ec6f9 388 int fd = open(path, O_RDONLY);
1f688557
JH
389 struct stat st;
390 if (fd < 0)
391 return -1;
392 if (fstat(fd, &st)) {
393 close(fd);
394 return -1;
395 }
396 idx_size = st.st_size;
397 idx_map = mmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
398 close(fd);
399 if (idx_map == MAP_FAILED)
400 return -1;
401
402 index = idx_map;
4d235c80
LT
403 *idx_map_ = idx_map;
404 *idx_size_ = idx_size;
1f688557
JH
405
406 /* check index map */
f9253394 407 if (idx_size < 4*256 + 20 + 20)
1f688557
JH
408 return error("index file too small");
409 nr = 0;
410 for (i = 0; i < 256; i++) {
411 unsigned int n = ntohl(index[i]);
412 if (n < nr)
413 return error("non-monotonic index");
414 nr = n;
415 }
416
417 /*
418 * Total size:
419 * - 256 index entries 4 bytes each
420 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
421 * - 20-byte SHA1 of the packfile
422 * - 20-byte SHA1 file checksum
423 */
424 if (idx_size != 4*256 + nr * 24 + 20 + 20)
425 return error("wrong index file size");
426
1f688557
JH
427 return 0;
428}
429
f9253394 430static int unuse_one_packed_git(void)
1f688557 431{
f9253394
JH
432 struct packed_git *p, *lru = NULL;
433
434 for (p = packed_git; p; p = p->next) {
435 if (p->pack_use_cnt || !p->pack_base)
436 continue;
437 if (!lru || p->pack_last_used < lru->pack_last_used)
438 lru = p;
439 }
440 if (!lru)
441 return 0;
442 munmap(lru->pack_base, lru->pack_size);
443 lru->pack_base = NULL;
444 return 1;
445}
446
447void unuse_packed_git(struct packed_git *p)
448{
449 p->pack_use_cnt--;
1f688557
JH
450}
451
f9253394 452int use_packed_git(struct packed_git *p)
1f688557 453{
bf592c50
DB
454 if (!p->pack_size) {
455 struct stat st;
a9486b02 456 /* We created the struct before we had the pack */
bf592c50
DB
457 stat(p->pack_name, &st);
458 if (!S_ISREG(st.st_mode))
459 die("packfile %s not a regular file", p->pack_name);
460 p->pack_size = st.st_size;
461 }
1f688557
JH
462 if (!p->pack_base) {
463 int fd;
464 struct stat st;
465 void *map;
466
467 pack_mapped += p->pack_size;
f9253394
JH
468 while (PACK_MAX_SZ < pack_mapped && unuse_one_packed_git())
469 ; /* nothing */
1f688557
JH
470 fd = open(p->pack_name, O_RDONLY);
471 if (fd < 0)
f9253394 472 die("packfile %s cannot be opened", p->pack_name);
1f688557
JH
473 if (fstat(fd, &st)) {
474 close(fd);
f9253394 475 die("packfile %s cannot be opened", p->pack_name);
1f688557
JH
476 }
477 if (st.st_size != p->pack_size)
f9253394 478 die("packfile %s size mismatch.", p->pack_name);
1f688557
JH
479 map = mmap(NULL, p->pack_size, PROT_READ, MAP_PRIVATE, fd, 0);
480 close(fd);
481 if (map == MAP_FAILED)
f9253394 482 die("packfile %s cannot be mapped.", p->pack_name);
1f688557 483 p->pack_base = map;
f9253394
JH
484
485 /* Check if the pack file matches with the index file.
486 * this is cheap.
487 */
488 if (memcmp((char*)(p->index_base) + p->index_size - 40,
1d7f171c
FF
489 (char *) p->pack_base + p->pack_size - 20,
490 20)) {
491
f9253394 492 die("packfile %s does not match index.", p->pack_name);
bf592c50 493 }
1f688557
JH
494 }
495 p->pack_last_used = pack_used_ctr++;
f9253394 496 p->pack_use_cnt++;
1f688557
JH
497 return 0;
498}
499
9d835df2 500struct packed_git *add_packed_git(char *path, int path_len, int local)
1f688557
JH
501{
502 struct stat st;
503 struct packed_git *p;
504 unsigned long idx_size;
505 void *idx_map;
c0bbbb1b 506 unsigned char sha1[20];
1f688557
JH
507
508 if (check_packed_git_idx(path, &idx_size, &idx_map))
509 return NULL;
510
511 /* do we have a corresponding .pack file? */
512 strcpy(path + path_len - 4, ".pack");
513 if (stat(path, &st) || !S_ISREG(st.st_mode)) {
514 munmap(idx_map, idx_size);
515 return NULL;
516 }
517 /* ok, it looks sane as far as we can check without
518 * actually mapping the pack file.
519 */
520 p = xmalloc(sizeof(*p) + path_len + 2);
521 strcpy(p->pack_name, path);
522 p->index_size = idx_size;
523 p->pack_size = st.st_size;
524 p->index_base = idx_map;
525 p->next = NULL;
d85a4fee 526 p->pack_base = NULL;
1f688557 527 p->pack_last_used = 0;
f9253394 528 p->pack_use_cnt = 0;
9d835df2 529 p->pack_local = local;
f4a11066 530 if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
c283ab21 531 memcpy(p->sha1, sha1, 20);
1f688557
JH
532 return p;
533}
534
bf592c50 535struct packed_git *parse_pack_index(unsigned char *sha1)
c508df5e
DB
536{
537 char *path = sha1_pack_index_name(sha1);
538 return parse_pack_index_file(sha1, path);
539}
540
2ab141a2 541struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path)
bf592c50
DB
542{
543 struct packed_git *p;
544 unsigned long idx_size;
545 void *idx_map;
c508df5e 546 char *path;
bf592c50 547
c508df5e 548 if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
bf592c50
DB
549 return NULL;
550
551 path = sha1_pack_name(sha1);
552
553 p = xmalloc(sizeof(*p) + strlen(path) + 2);
554 strcpy(p->pack_name, path);
555 p->index_size = idx_size;
556 p->pack_size = 0;
557 p->index_base = idx_map;
558 p->next = NULL;
559 p->pack_base = NULL;
560 p->pack_last_used = 0;
561 p->pack_use_cnt = 0;
562 memcpy(p->sha1, sha1, 20);
563 return p;
564}
565
566void install_packed_git(struct packed_git *pack)
567{
568 pack->next = packed_git;
569 packed_git = pack;
570}
571
9d835df2 572static void prepare_packed_git_one(char *objdir, int local)
1f688557
JH
573{
574 char path[PATH_MAX];
575 int len;
576 DIR *dir;
577 struct dirent *de;
578
579 sprintf(path, "%s/pack", objdir);
580 len = strlen(path);
581 dir = opendir(path);
b5b16990 582 if (!dir) {
26125f6b 583 if (errno != ENOENT)
bd2afde8 584 error("unable to open object pack directory: %s: %s",
26125f6b 585 path, strerror(errno));
1f688557 586 return;
b5b16990 587 }
1f688557
JH
588 path[len++] = '/';
589 while ((de = readdir(dir)) != NULL) {
590 int namelen = strlen(de->d_name);
591 struct packed_git *p;
592
593 if (strcmp(de->d_name + namelen - 4, ".idx"))
594 continue;
595
596 /* we have .idx. Is it a file we can map? */
597 strcpy(path + len, de->d_name);
86f7780c
JK
598 for (p = packed_git; p; p = p->next) {
599 if (!memcmp(path, p->pack_name, len + namelen - 4))
600 break;
601 }
602 if (p)
603 continue;
9d835df2 604 p = add_packed_git(path, len + namelen, local);
1f688557
JH
605 if (!p)
606 continue;
607 p->next = packed_git;
608 packed_git = p;
609 }
5b35bcd5 610 closedir(dir);
1f688557
JH
611}
612
637cdd9d 613static int prepare_packed_git_run_once = 0;
9a217f2a 614void prepare_packed_git(void)
1f688557 615{
d5a63b99 616 struct alternate_object_database *alt;
1f688557 617
637cdd9d 618 if (prepare_packed_git_run_once)
1f688557 619 return;
9d835df2 620 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 621 prepare_alt_odb();
d5a63b99 622 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 623 alt->name[-1] = 0;
9d835df2 624 prepare_packed_git_one(alt->base, 0);
1494e038 625 alt->name[-1] = '/';
1f688557 626 }
637cdd9d
JK
627 prepare_packed_git_run_once = 1;
628}
629
630static void reprepare_packed_git(void)
631{
632 prepare_packed_git_run_once = 0;
633 prepare_packed_git();
1f688557
JH
634}
635
5d6ccf5c 636int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
0fcfd160 637{
d98b46f8 638 char header[100];
0fcfd160
LT
639 unsigned char real_sha1[20];
640 SHA_CTX c;
641
642 SHA1_Init(&c);
d98b46f8 643 SHA1_Update(&c, header, 1+sprintf(header, "%s %lu", type, size));
0fcfd160
LT
644 SHA1_Update(&c, map, size);
645 SHA1_Final(real_sha1, &c);
646 return memcmp(sha1, real_sha1, 20) ? -1 : 0;
647}
648
1f688557 649static void *map_sha1_file_internal(const unsigned char *sha1,
d5f1befc 650 unsigned long *size)
0fcfd160 651{
0fcfd160
LT
652 struct stat st;
653 void *map;
144bde78 654 int fd;
ace1534d
JH
655 char *filename = find_sha1_file(sha1, &st);
656
657 if (!filename) {
ace1534d
JH
658 return NULL;
659 }
0fcfd160 660
144bde78 661 fd = open(filename, O_RDONLY | sha1_file_open_flag);
0fcfd160 662 if (fd < 0) {
144bde78
LT
663 /* See if it works without O_NOATIME */
664 switch (sha1_file_open_flag) {
665 default:
666 fd = open(filename, O_RDONLY);
667 if (fd >= 0)
668 break;
669 /* Fallthrough */
670 case 0:
144bde78
LT
671 return NULL;
672 }
673
1f688557
JH
674 /* If it failed once, it will probably fail again.
675 * Stop using O_NOATIME
676 */
144bde78 677 sha1_file_open_flag = 0;
0fcfd160 678 }
0fcfd160
LT
679 map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
680 close(fd);
e35f9824 681 if (map == MAP_FAILED)
0fcfd160
LT
682 return NULL;
683 *size = st.st_size;
684 return map;
685}
686
93821bd9 687static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
c4483576 688{
93821bd9
LT
689 unsigned char c;
690 unsigned int word, bits;
691 unsigned long size;
692 static const char *typename[8] = {
693 NULL, /* OBJ_EXT */
694 "commit", "tree", "blob", "tag",
695 NULL, NULL, NULL
696 };
697 const char *type;
698
c4483576
LT
699 /* Get the data stream */
700 memset(stream, 0, sizeof(*stream));
701 stream->next_in = map;
702 stream->avail_in = mapsize;
703 stream->next_out = buffer;
93821bd9
LT
704 stream->avail_out = bufsiz;
705
706 /*
707 * Is it a zlib-compressed buffer? If so, the first byte
708 * must be 0x78 (15-bit window size, deflated), and the
709 * first 16-bit word is evenly divisible by 31
710 */
711 word = (map[0] << 8) + map[1];
712 if (map[0] == 0x78 && !(word % 31)) {
713 inflateInit(stream);
714 return inflate(stream, 0);
715 }
716
717 c = *map++;
718 mapsize--;
719 type = typename[(c >> 4) & 7];
720 if (!type)
721 return -1;
c4483576 722
93821bd9
LT
723 bits = 4;
724 size = c & 0xf;
725 while ((c & 0x80)) {
726 if (bits >= 8*sizeof(long))
727 return -1;
728 c = *map++;
729 size += (c & 0x7f) << bits;
730 bits += 7;
731 mapsize--;
732 }
733
734 /* Set up the stream for the rest.. */
735 stream->next_in = map;
736 stream->avail_in = mapsize;
c4483576 737 inflateInit(stream);
93821bd9
LT
738
739 /* And generate the fake traditional header */
740 stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu", type, size);
741 return 0;
c4483576
LT
742}
743
6da4016a 744static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
5180cacc
LT
745{
746 int bytes = strlen(buffer) + 1;
d565b341 747 unsigned char *buf = xmalloc(1+size);
93821bd9 748 unsigned long n;
5180cacc 749
93821bd9
LT
750 n = stream->total_out - bytes;
751 if (n > size)
752 n = size;
753 memcpy(buf, (char *) buffer + bytes, n);
754 bytes = n;
5180cacc
LT
755 if (bytes < size) {
756 stream->next_out = buf + bytes;
757 stream->avail_out = size - bytes;
758 while (inflate(stream, Z_FINISH) == Z_OK)
759 /* nothing */;
760 }
761 buf[size] = 0;
762 inflateEnd(stream);
763 return buf;
764}
765
766/*
767 * We used to just use "sscanf()", but that's actually way
768 * too permissive for what we want to check. So do an anal
769 * object header parse by hand.
770 */
38d3874d 771static int parse_sha1_header(char *hdr, char *type, unsigned long *sizep)
5180cacc
LT
772{
773 int i;
774 unsigned long size;
775
776 /*
777 * The type can be at most ten bytes (including the
778 * terminating '\0' that we add), and is followed by
779 * a space.
780 */
781 i = 10;
782 for (;;) {
783 char c = *hdr++;
784 if (c == ' ')
785 break;
786 if (!--i)
787 return -1;
788 *type++ = c;
789 }
790 *type = 0;
791
792 /*
793 * The length must follow immediately, and be in canonical
794 * decimal format (ie "010" is not valid).
795 */
796 size = *hdr++ - '0';
797 if (size > 9)
798 return -1;
799 if (size) {
800 for (;;) {
801 unsigned long c = *hdr - '0';
802 if (c > 9)
803 break;
804 hdr++;
805 size = size * 10 + c;
806 }
807 }
808 *sizep = size;
809
810 /*
811 * The length must be followed by a zero byte
812 */
813 return *hdr ? -1 : 0;
814}
815
0fcfd160
LT
816void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
817{
5180cacc 818 int ret;
0fcfd160 819 z_stream stream;
5180cacc 820 char hdr[8192];
0fcfd160 821
5180cacc
LT
822 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
823 if (ret < Z_OK || parse_sha1_header(hdr, type, size) < 0)
0fcfd160
LT
824 return NULL;
825
5180cacc 826 return unpack_sha1_rest(&stream, hdr, *size);
0fcfd160
LT
827}
828
f3bf9224
JH
829/* forward declaration for a mutually recursive function */
830static int packed_object_info(struct pack_entry *entry,
831 char *type, unsigned long *sizep);
832
5db47c2b
JH
833static int packed_delta_info(unsigned char *base_sha1,
834 unsigned long delta_size,
835 unsigned long left,
836 char *type,
f3bf9224
JH
837 unsigned long *sizep,
838 struct packed_git *p)
5db47c2b 839{
f3bf9224
JH
840 struct pack_entry base_ent;
841
5db47c2b
JH
842 if (left < 20)
843 die("truncated pack file");
5db47c2b 844
f3bf9224
JH
845 /* The base entry _must_ be in the same pack */
846 if (!find_pack_entry_one(base_sha1, &base_ent, p))
847 die("failed to find delta-pack base object %s",
848 sha1_to_hex(base_sha1));
849
c62266f3
JH
850 /* We choose to only get the type of the base object and
851 * ignore potentially corrupt pack file that expects the delta
852 * based on a base with a wrong size. This saves tons of
853 * inflate() calls.
854 */
5db47c2b 855
f3bf9224 856 if (packed_object_info(&base_ent, type, NULL))
c62266f3 857 die("cannot get info for delta-pack base");
5db47c2b 858
c62266f3
JH
859 if (sizep) {
860 const unsigned char *data;
861 unsigned char delta_head[64];
862 unsigned long result_size;
863 z_stream stream;
864 int st;
865
866 memset(&stream, 0, sizeof(stream));
867
868 data = stream.next_in = base_sha1 + 20;
869 stream.avail_in = left - 20;
870 stream.next_out = delta_head;
871 stream.avail_out = sizeof(delta_head);
872
873 inflateInit(&stream);
874 st = inflate(&stream, Z_FINISH);
875 inflateEnd(&stream);
876 if ((st != Z_STREAM_END) &&
877 stream.total_out != sizeof(delta_head))
878 die("delta data unpack-initial failed");
879
880 /* Examine the initial part of the delta to figure out
881 * the result size.
882 */
883 data = delta_head;
8960844a
NP
884
885 /* ignore base size */
886 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
5db47c2b 887
c62266f3 888 /* Read the result size */
8960844a 889 result_size = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
c62266f3
JH
890 *sizep = result_size;
891 }
5db47c2b
JH
892 return 0;
893}
894
a733cb60
LT
895static unsigned long unpack_object_header(struct packed_git *p, unsigned long offset,
896 enum object_type *type, unsigned long *sizep)
897{
01247d87 898 unsigned shift;
a733cb60
LT
899 unsigned char *pack, c;
900 unsigned long size;
901
902 if (offset >= p->pack_size)
903 die("object offset outside of pack file");
904
1d7f171c 905 pack = (unsigned char *) p->pack_base + offset;
a733cb60
LT
906 c = *pack++;
907 offset++;
908 *type = (c >> 4) & 7;
909 size = c & 15;
01247d87 910 shift = 4;
a733cb60
LT
911 while (c & 0x80) {
912 if (offset >= p->pack_size)
913 die("object offset outside of pack file");
914 c = *pack++;
915 offset++;
01247d87
LT
916 size += (c & 0x7f) << shift;
917 shift += 7;
a733cb60
LT
918 }
919 *sizep = size;
920 return offset;
921}
922
a49dd05f
JH
923int check_reuse_pack_delta(struct packed_git *p, unsigned long offset,
924 unsigned char *base, unsigned long *sizep,
925 enum object_type *kindp)
926{
927 unsigned long ptr;
928 int status = -1;
929
930 use_packed_git(p);
931 ptr = offset;
932 ptr = unpack_object_header(p, ptr, kindp, sizep);
933 if (*kindp != OBJ_DELTA)
934 goto done;
1d7f171c 935 memcpy(base, (char *) p->pack_base + ptr, 20);
a49dd05f
JH
936 status = 0;
937 done:
938 unuse_packed_git(p);
939 return status;
940}
941
ad8c80a5
JH
942void packed_object_info_detail(struct pack_entry *e,
943 char *type,
944 unsigned long *size,
945 unsigned long *store_size,
f8f135c9 946 unsigned int *delta_chain_length,
ad8c80a5
JH
947 unsigned char *base_sha1)
948{
949 struct packed_git *p = e->p;
2855d580 950 unsigned long offset;
ad8c80a5
JH
951 unsigned char *pack;
952 enum object_type kind;
953
954 offset = unpack_object_header(p, e->offset, &kind, size);
1d7f171c 955 pack = (unsigned char *) p->pack_base + offset;
ad8c80a5
JH
956 if (kind != OBJ_DELTA)
957 *delta_chain_length = 0;
958 else {
f8f135c9 959 unsigned int chain_length = 0;
2855d580
JH
960 if (p->pack_size <= offset + 20)
961 die("pack file %s records an incomplete delta base",
962 p->pack_name);
ad8c80a5
JH
963 memcpy(base_sha1, pack, 20);
964 do {
965 struct pack_entry base_ent;
966 unsigned long junk;
967
968 find_pack_entry_one(pack, &base_ent, p);
969 offset = unpack_object_header(p, base_ent.offset,
970 &kind, &junk);
1d7f171c 971 pack = (unsigned char *) p->pack_base + offset;
ad8c80a5
JH
972 chain_length++;
973 } while (kind == OBJ_DELTA);
974 *delta_chain_length = chain_length;
975 }
976 switch (kind) {
977 case OBJ_COMMIT:
8e440259 978 strcpy(type, commit_type);
ad8c80a5
JH
979 break;
980 case OBJ_TREE:
8e440259 981 strcpy(type, tree_type);
ad8c80a5
JH
982 break;
983 case OBJ_BLOB:
8e440259 984 strcpy(type, blob_type);
ad8c80a5
JH
985 break;
986 case OBJ_TAG:
8e440259 987 strcpy(type, tag_type);
ad8c80a5
JH
988 break;
989 default:
264b16b6
JH
990 die("corrupted pack file %s containing object of kind %d",
991 p->pack_name, kind);
ad8c80a5
JH
992 }
993 *store_size = 0; /* notyet */
994}
995
1f688557
JH
996static int packed_object_info(struct pack_entry *entry,
997 char *type, unsigned long *sizep)
998{
999 struct packed_git *p = entry->p;
1000 unsigned long offset, size, left;
1001 unsigned char *pack;
a733cb60 1002 enum object_type kind;
f9253394 1003 int retval;
5db47c2b
JH
1004
1005 if (use_packed_git(p))
1006 die("cannot map packed file");
1007
a733cb60 1008 offset = unpack_object_header(p, entry->offset, &kind, &size);
1d7f171c 1009 pack = (unsigned char *) p->pack_base + offset;
a733cb60
LT
1010 left = p->pack_size - offset;
1011
1012 switch (kind) {
1013 case OBJ_DELTA:
f3bf9224 1014 retval = packed_delta_info(pack, size, left, type, sizep, p);
f9253394
JH
1015 unuse_packed_git(p);
1016 return retval;
a733cb60 1017 case OBJ_COMMIT:
8e440259 1018 strcpy(type, commit_type);
1f688557 1019 break;
a733cb60 1020 case OBJ_TREE:
8e440259 1021 strcpy(type, tree_type);
1f688557 1022 break;
a733cb60 1023 case OBJ_BLOB:
8e440259 1024 strcpy(type, blob_type);
1f688557 1025 break;
a733cb60 1026 case OBJ_TAG:
8e440259 1027 strcpy(type, tag_type);
a69d0943 1028 break;
1f688557 1029 default:
264b16b6
JH
1030 die("corrupted pack file %s containing object of kind %d",
1031 p->pack_name, kind);
1f688557 1032 }
c62266f3
JH
1033 if (sizep)
1034 *sizep = size;
f9253394 1035 unuse_packed_git(p);
1f688557
JH
1036 return 0;
1037}
1038
1039/* forward declaration for a mutually recursive function */
1040static void *unpack_entry(struct pack_entry *, char *, unsigned long *);
1041
1042static void *unpack_delta_entry(unsigned char *base_sha1,
1043 unsigned long delta_size,
1044 unsigned long left,
1045 char *type,
f3bf9224
JH
1046 unsigned long *sizep,
1047 struct packed_git *p)
1f688557 1048{
f3bf9224 1049 struct pack_entry base_ent;
1f688557
JH
1050 void *data, *delta_data, *result, *base;
1051 unsigned long data_size, result_size, base_size;
1052 z_stream stream;
1053 int st;
1054
1055 if (left < 20)
1056 die("truncated pack file");
67686d95
JH
1057
1058 /* The base entry _must_ be in the same pack */
1059 if (!find_pack_entry_one(base_sha1, &base_ent, p))
1060 die("failed to find delta-pack base object %s",
1061 sha1_to_hex(base_sha1));
1062 base = unpack_entry_gently(&base_ent, type, &base_size);
1063 if (!base)
1064 die("failed to read delta-pack base object %s",
1065 sha1_to_hex(base_sha1));
1066
1f688557
JH
1067 data = base_sha1 + 20;
1068 data_size = left - 20;
1069 delta_data = xmalloc(delta_size);
1070
1071 memset(&stream, 0, sizeof(stream));
1072
1073 stream.next_in = data;
1074 stream.avail_in = data_size;
1075 stream.next_out = delta_data;
1076 stream.avail_out = delta_size;
1077
1078 inflateInit(&stream);
1079 st = inflate(&stream, Z_FINISH);
1080 inflateEnd(&stream);
1081 if ((st != Z_STREAM_END) || stream.total_out != delta_size)
1082 die("delta data unpack failed");
1083
1f688557
JH
1084 result = patch_delta(base, base_size,
1085 delta_data, delta_size,
1086 &result_size);
1087 if (!result)
1088 die("failed to apply delta");
1089 free(delta_data);
1090 free(base);
1091 *sizep = result_size;
1092 return result;
1093}
1094
1095static void *unpack_non_delta_entry(unsigned char *data,
1096 unsigned long size,
1097 unsigned long left)
1098{
1099 int st;
1100 z_stream stream;
4d235c80 1101 unsigned char *buffer;
1f688557
JH
1102
1103 buffer = xmalloc(size + 1);
1104 buffer[size] = 0;
1105 memset(&stream, 0, sizeof(stream));
1106 stream.next_in = data;
1107 stream.avail_in = left;
1108 stream.next_out = buffer;
1109 stream.avail_out = size;
1110
1111 inflateInit(&stream);
1112 st = inflate(&stream, Z_FINISH);
1113 inflateEnd(&stream);
1114 if ((st != Z_STREAM_END) || stream.total_out != size) {
1115 free(buffer);
1116 return NULL;
1117 }
1118
1119 return buffer;
1120}
1121
1122static void *unpack_entry(struct pack_entry *entry,
1123 char *type, unsigned long *sizep)
1124{
1125 struct packed_git *p = entry->p;
f9253394 1126 void *retval;
1f688557
JH
1127
1128 if (use_packed_git(p))
1129 die("cannot map packed file");
f3bf9224
JH
1130 retval = unpack_entry_gently(entry, type, sizep);
1131 unuse_packed_git(p);
1132 if (!retval)
264b16b6 1133 die("corrupted pack file %s", p->pack_name);
f3bf9224
JH
1134 return retval;
1135}
1136
1137/* The caller is responsible for use_packed_git()/unuse_packed_git() pair */
1138void *unpack_entry_gently(struct pack_entry *entry,
1139 char *type, unsigned long *sizep)
1140{
1141 struct packed_git *p = entry->p;
1142 unsigned long offset, size, left;
1143 unsigned char *pack;
1144 enum object_type kind;
1145 void *retval;
1f688557 1146
a733cb60 1147 offset = unpack_object_header(p, entry->offset, &kind, &size);
1d7f171c 1148 pack = (unsigned char *) p->pack_base + offset;
a733cb60
LT
1149 left = p->pack_size - offset;
1150 switch (kind) {
1151 case OBJ_DELTA:
f3bf9224 1152 retval = unpack_delta_entry(pack, size, left, type, sizep, p);
f9253394 1153 return retval;
a733cb60 1154 case OBJ_COMMIT:
8e440259 1155 strcpy(type, commit_type);
1f688557 1156 break;
a733cb60 1157 case OBJ_TREE:
8e440259 1158 strcpy(type, tree_type);
1f688557 1159 break;
a733cb60 1160 case OBJ_BLOB:
8e440259 1161 strcpy(type, blob_type);
1f688557 1162 break;
a733cb60 1163 case OBJ_TAG:
8e440259 1164 strcpy(type, tag_type);
a69d0943 1165 break;
1f688557 1166 default:
f3bf9224 1167 return NULL;
1f688557
JH
1168 }
1169 *sizep = size;
f9253394 1170 retval = unpack_non_delta_entry(pack, size, left);
f9253394 1171 return retval;
1f688557
JH
1172}
1173
9a217f2a
JH
1174int num_packed_objects(const struct packed_git *p)
1175{
f9253394 1176 /* See check_packed_git_idx() */
9a217f2a
JH
1177 return (p->index_size - 20 - 20 - 4*256) / 24;
1178}
1179
1180int nth_packed_object_sha1(const struct packed_git *p, int n,
1181 unsigned char* sha1)
1182{
1183 void *index = p->index_base + 256;
1184 if (n < 0 || num_packed_objects(p) <= n)
1185 return -1;
1d7f171c 1186 memcpy(sha1, (char *) index + (24 * n) + 4, 20);
9a217f2a
JH
1187 return 0;
1188}
1189
f3bf9224
JH
1190int find_pack_entry_one(const unsigned char *sha1,
1191 struct pack_entry *e, struct packed_git *p)
1f688557 1192{
4d235c80 1193 unsigned int *level1_ofs = p->index_base;
1f688557
JH
1194 int hi = ntohl(level1_ofs[*sha1]);
1195 int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
1196 void *index = p->index_base + 256;
1197
1198 do {
1199 int mi = (lo + hi) / 2;
1d7f171c 1200 int cmp = memcmp((char *) index + (24 * mi) + 4, sha1, 20);
1f688557 1201 if (!cmp) {
1d7f171c 1202 e->offset = ntohl(*((unsigned int *) ((char *) index + (24 * mi))));
1f688557
JH
1203 memcpy(e->sha1, sha1, 20);
1204 e->p = p;
1205 return 1;
1206 }
1207 if (cmp > 0)
1208 hi = mi;
1209 else
1210 lo = mi+1;
1211 } while (lo < hi);
1212 return 0;
1213}
1214
1215static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
1216{
1217 struct packed_git *p;
1218 prepare_packed_git();
1219
1220 for (p = packed_git; p; p = p->next) {
f3bf9224 1221 if (find_pack_entry_one(sha1, e, p))
1f688557
JH
1222 return 1;
1223 }
1224 return 0;
1225}
1226
bf592c50
DB
1227struct packed_git *find_sha1_pack(const unsigned char *sha1,
1228 struct packed_git *packs)
1229{
1230 struct packed_git *p;
1231 struct pack_entry e;
1232
1233 for (p = packs; p; p = p->next) {
1234 if (find_pack_entry_one(sha1, &e, p))
1235 return p;
1236 }
1237 return NULL;
1238
1239}
1240
36e4d74a 1241int sha1_object_info(const unsigned char *sha1, char *type, unsigned long *sizep)
65c2e0c3 1242{
36e4d74a 1243 int status;
65c2e0c3
JH
1244 unsigned long mapsize, size;
1245 void *map;
1246 z_stream stream;
36e4d74a 1247 char hdr[128];
65c2e0c3 1248
d5f1befc 1249 map = map_sha1_file_internal(sha1, &mapsize);
1f688557
JH
1250 if (!map) {
1251 struct pack_entry e;
1252
637cdd9d
JK
1253 if (find_pack_entry(sha1, &e))
1254 return packed_object_info(&e, type, sizep);
1255 reprepare_packed_git();
1256 if (find_pack_entry(sha1, &e))
1257 return packed_object_info(&e, type, sizep);
1258 return error("unable to find %s", sha1_to_hex(sha1));
1f688557 1259 }
36e4d74a
JH
1260 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1261 status = error("unable to unpack %s header",
1262 sha1_to_hex(sha1));
1263 if (parse_sha1_header(hdr, type, &size) < 0)
1264 status = error("unable to parse %s header", sha1_to_hex(sha1));
c4584ae3 1265 else {
65c2e0c3 1266 status = 0;
c62266f3
JH
1267 if (sizep)
1268 *sizep = size;
65c2e0c3 1269 }
65c2e0c3
JH
1270 inflateEnd(&stream);
1271 munmap(map, mapsize);
1272 return status;
1273}
1274
1f688557
JH
1275static void *read_packed_sha1(const unsigned char *sha1, char *type, unsigned long *size)
1276{
1277 struct pack_entry e;
1278
1279 if (!find_pack_entry(sha1, &e)) {
1280 error("cannot read sha1_file for %s", sha1_to_hex(sha1));
1281 return NULL;
1282 }
1283 return unpack_entry(&e, type, size);
1284}
1285
0fcfd160
LT
1286void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size)
1287{
1288 unsigned long mapsize;
1289 void *map, *buf;
ab90ea5d 1290 struct pack_entry e;
0fcfd160 1291
ab90ea5d
JH
1292 if (find_pack_entry(sha1, &e))
1293 return read_packed_sha1(sha1, type, size);
d5f1befc 1294 map = map_sha1_file_internal(sha1, &mapsize);
0fcfd160
LT
1295 if (map) {
1296 buf = unpack_sha1_file(map, mapsize, type, size);
1297 munmap(map, mapsize);
1298 return buf;
1299 }
637cdd9d
JK
1300 reprepare_packed_git();
1301 if (find_pack_entry(sha1, &e))
1302 return read_packed_sha1(sha1, type, size);
ab90ea5d 1303 return NULL;
0fcfd160
LT
1304}
1305
40469ee9 1306void *read_object_with_reference(const unsigned char *sha1,
bf0f910d 1307 const char *required_type,
40469ee9
JH
1308 unsigned long *size,
1309 unsigned char *actual_sha1_return)
f4913f91
JH
1310{
1311 char type[20];
1312 void *buffer;
1313 unsigned long isize;
40469ee9 1314 unsigned char actual_sha1[20];
f4913f91 1315
40469ee9
JH
1316 memcpy(actual_sha1, sha1, 20);
1317 while (1) {
1318 int ref_length = -1;
1319 const char *ref_type = NULL;
f4913f91 1320
40469ee9
JH
1321 buffer = read_sha1_file(actual_sha1, type, &isize);
1322 if (!buffer)
1323 return NULL;
1324 if (!strcmp(type, required_type)) {
1325 *size = isize;
1326 if (actual_sha1_return)
1327 memcpy(actual_sha1_return, actual_sha1, 20);
1328 return buffer;
1329 }
1330 /* Handle references */
8e440259 1331 else if (!strcmp(type, commit_type))
40469ee9 1332 ref_type = "tree ";
8e440259 1333 else if (!strcmp(type, tag_type))
40469ee9
JH
1334 ref_type = "object ";
1335 else {
1336 free(buffer);
1337 return NULL;
1338 }
1339 ref_length = strlen(ref_type);
f4913f91 1340
40469ee9 1341 if (memcmp(buffer, ref_type, ref_length) ||
1d7f171c 1342 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
1343 free(buffer);
1344 return NULL;
1345 }
1cf58e72 1346 free(buffer);
40469ee9
JH
1347 /* Now we have the ID of the referred-to object in
1348 * actual_sha1. Check again. */
f4913f91 1349 }
f4913f91
JH
1350}
1351
7672db20
BL
1352char *write_sha1_file_prepare(void *buf,
1353 unsigned long len,
1354 const char *type,
1355 unsigned char *sha1,
1356 unsigned char *hdr,
1357 int *hdrlen)
d410c0f5
JH
1358{
1359 SHA_CTX c;
1360
1361 /* Generate the header */
1362 *hdrlen = sprintf((char *)hdr, "%s %lu", type, len)+1;
1363
1364 /* Sha1.. */
1365 SHA1_Init(&c);
1366 SHA1_Update(&c, hdr, *hdrlen);
1367 SHA1_Update(&c, buf, len);
1368 SHA1_Final(sha1, &c);
1369
1370 return sha1_file_name(sha1);
1371}
1372
230f1322
LT
1373/*
1374 * Link the tempfile to the final place, possibly creating the
1375 * last directory level as you do so.
1376 *
1377 * Returns the errno on failure, 0 on success.
1378 */
1379static int link_temp_to_file(const char *tmpfile, char *filename)
1380{
1381 int ret;
756aaf4a 1382 char *dir;
230f1322
LT
1383
1384 if (!link(tmpfile, filename))
1385 return 0;
1386
1387 /*
756aaf4a 1388 * Try to mkdir the last path component if that failed.
230f1322
LT
1389 *
1390 * Re-try the "link()" regardless of whether the mkdir
1391 * succeeds, since a race might mean that somebody
1392 * else succeeded.
1393 */
1394 ret = errno;
756aaf4a
SP
1395 dir = strrchr(filename, '/');
1396 if (dir) {
1397 *dir = 0;
1398 mkdir(filename, 0777);
1399 if (adjust_shared_perm(filename))
1400 return -2;
1401 *dir = '/';
1402 if (!link(tmpfile, filename))
1403 return 0;
1404 ret = errno;
230f1322
LT
1405 }
1406 return ret;
1407}
1408
1409/*
1410 * Move the just written object into its final resting place
1411 */
b721e01f 1412int move_temp_to_file(const char *tmpfile, char *filename)
230f1322
LT
1413{
1414 int ret = link_temp_to_file(tmpfile, filename);
7ebb6fca
LT
1415
1416 /*
1417 * Coda hack - coda doesn't like cross-directory links,
1418 * so we fall back to a rename, which will mean that it
1419 * won't be able to check collisions, but that's not a
1420 * big deal.
1421 *
1422 * The same holds for FAT formatted media.
1423 *
1424 * When this succeeds, we just return 0. We have nothing
1425 * left to unlink.
1426 */
1427 if (ret && ret != EEXIST) {
1428 if (!rename(tmpfile, filename))
230f1322 1429 return 0;
9e48b389 1430 ret = errno;
230f1322
LT
1431 }
1432 unlink(tmpfile);
1433 if (ret) {
1434 if (ret != EEXIST) {
7246ed43 1435 fprintf(stderr, "unable to write sha1 filename %s: %s\n", filename, strerror(ret));
230f1322
LT
1436 return -1;
1437 }
1438 /* FIXME!!! Collision check here ? */
1439 }
1440
1441 return 0;
1442}
1443
4d548150
LT
1444static int write_buffer(int fd, const void *buf, size_t len)
1445{
1446 while (len) {
1447 ssize_t size;
1448
1449 size = write(fd, buf, len);
1450 if (!size)
1451 return error("file write: disk full");
1452 if (size < 0) {
1453 if (errno == EINTR || errno == EAGAIN)
1454 continue;
1455 return error("file write error (%s)", strerror(errno));
1456 }
1457 len -= size;
1d7f171c 1458 buf = (char *) buf + size;
4d548150
LT
1459 }
1460 return 0;
1461}
1462
93821bd9
LT
1463static int write_binary_header(unsigned char *hdr, enum object_type type, unsigned long len)
1464{
1465 int hdr_len;
1466 unsigned char c;
1467
1468 c = (type << 4) | (len & 15);
1469 len >>= 4;
1470 hdr_len = 1;
1471 while (len) {
1472 *hdr++ = c | 0x80;
1473 hdr_len++;
1474 c = (len & 0x7f);
1475 len >>= 7;
1476 }
1477 *hdr = c;
1478 return hdr_len;
1479}
1480
1481static void setup_object_header(z_stream *stream, const char *type, unsigned long len)
1482{
1483 int obj_type, hdr;
1484
1485 if (use_legacy_headers) {
1486 while (deflate(stream, 0) == Z_OK)
1487 /* nothing */;
1488 return;
1489 }
1490 if (!strcmp(type, blob_type))
1491 obj_type = OBJ_BLOB;
1492 else if (!strcmp(type, tree_type))
1493 obj_type = OBJ_TREE;
1494 else if (!strcmp(type, commit_type))
1495 obj_type = OBJ_COMMIT;
1496 else if (!strcmp(type, tag_type))
1497 obj_type = OBJ_TAG;
1498 else
1499 die("trying to generate bogus object of type '%s'", type);
1500 hdr = write_binary_header(stream->next_out, obj_type, len);
1501 stream->total_out = hdr;
1502 stream->next_out += hdr;
1503 stream->avail_out -= hdr;
1504}
1505
bf0f910d 1506int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
0fcfd160
LT
1507{
1508 int size;
bf0f910d 1509 unsigned char *compressed;
0fcfd160
LT
1510 z_stream stream;
1511 unsigned char sha1[20];
706bc531 1512 char *filename;
aac17941 1513 static char tmpfile[PATH_MAX];
bf0f910d 1514 unsigned char hdr[50];
230f1322 1515 int fd, hdrlen;
a44c9a5e 1516
d410c0f5
JH
1517 /* Normally if we have it in the pack then we do not bother writing
1518 * it out into .git/objects/??/?{38} file.
1519 */
1520 filename = write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
706bc531
LT
1521 if (returnsha1)
1522 memcpy(returnsha1, sha1, 20);
d410c0f5
JH
1523 if (has_sha1_file(sha1))
1524 return 0;
aac17941
LT
1525 fd = open(filename, O_RDONLY);
1526 if (fd >= 0) {
706bc531 1527 /*
aac17941
LT
1528 * FIXME!!! We might do collision checking here, but we'd
1529 * need to uncompress the old file and check it. Later.
706bc531 1530 */
aac17941 1531 close(fd);
706bc531
LT
1532 return 0;
1533 }
1534
aac17941 1535 if (errno != ENOENT) {
7246ed43 1536 fprintf(stderr, "sha1 file %s: %s\n", filename, strerror(errno));
aac17941
LT
1537 return -1;
1538 }
1539
1540 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
ace1534d 1541
aac17941
LT
1542 fd = mkstemp(tmpfile);
1543 if (fd < 0) {
7246ed43 1544 fprintf(stderr, "unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
aac17941
LT
1545 return -1;
1546 }
1547
0fcfd160
LT
1548 /* Set it up */
1549 memset(&stream, 0, sizeof(stream));
12f6c308 1550 deflateInit(&stream, zlib_compression_level);
93821bd9 1551 size = 8 + deflateBound(&stream, len+hdrlen);
812666c8 1552 compressed = xmalloc(size);
0fcfd160
LT
1553
1554 /* Compress it */
0fcfd160
LT
1555 stream.next_out = compressed;
1556 stream.avail_out = size;
a44c9a5e
LT
1557
1558 /* First header.. */
1559 stream.next_in = hdr;
1560 stream.avail_in = hdrlen;
93821bd9 1561 setup_object_header(&stream, type, len);
a44c9a5e
LT
1562
1563 /* Then the data itself.. */
1564 stream.next_in = buf;
1565 stream.avail_in = len;
0fcfd160
LT
1566 while (deflate(&stream, Z_FINISH) == Z_OK)
1567 /* nothing */;
1568 deflateEnd(&stream);
1569 size = stream.total_out;
1570
4d548150
LT
1571 if (write_buffer(fd, compressed, size) < 0)
1572 die("unable to write sha1 file");
aac17941 1573 fchmod(fd, 0444);
706bc531 1574 close(fd);
383f85b7 1575 free(compressed);
0fcfd160 1576
230f1322 1577 return move_temp_to_file(tmpfile, filename);
0fcfd160 1578}
8237b185 1579
4d548150
LT
1580/*
1581 * We need to unpack and recompress the object for writing
1582 * it out to a different file.
1583 */
1584static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
a5eda52b 1585{
4d548150 1586 size_t size;
a5eda52b 1587 z_stream stream;
4d548150
LT
1588 unsigned char *unpacked;
1589 unsigned long len;
1590 char type[20];
1591 char hdr[50];
1592 int hdrlen;
1593 void *buf;
bfc66daf 1594
a9486b02 1595 /* need to unpack and recompress it by itself */
4d548150 1596 unpacked = read_packed_sha1(sha1, type, &len);
a5eda52b 1597
4d548150 1598 hdrlen = sprintf(hdr, "%s %lu", type, len) + 1;
a5eda52b 1599
4d548150
LT
1600 /* Set it up */
1601 memset(&stream, 0, sizeof(stream));
12f6c308 1602 deflateInit(&stream, zlib_compression_level);
4d548150
LT
1603 size = deflateBound(&stream, len + hdrlen);
1604 buf = xmalloc(size);
a5eda52b 1605
4d548150
LT
1606 /* Compress it */
1607 stream.next_out = buf;
1608 stream.avail_out = size;
a5eda52b 1609
4d548150
LT
1610 /* First header.. */
1611 stream.next_in = (void *)hdr;
1612 stream.avail_in = hdrlen;
1613 while (deflate(&stream, 0) == Z_OK)
1614 /* nothing */;
bfc66daf 1615
4d548150
LT
1616 /* Then the data itself.. */
1617 stream.next_in = unpacked;
1618 stream.avail_in = len;
1619 while (deflate(&stream, Z_FINISH) == Z_OK)
1620 /* nothing */;
1621 deflateEnd(&stream);
1622 free(unpacked);
bfc66daf 1623
4d548150
LT
1624 *objsize = stream.total_out;
1625 return buf;
1626}
1627
1628int write_sha1_to_fd(int fd, const unsigned char *sha1)
1629{
1630 int retval;
1631 unsigned long objsize;
1632 void *buf = map_sha1_file_internal(sha1, &objsize);
1633
1634 if (buf) {
1635 retval = write_buffer(fd, buf, objsize);
1636 munmap(buf, objsize);
1637 return retval;
1638 }
1639
1640 buf = repack_object(sha1, &objsize);
1641 retval = write_buffer(fd, buf, objsize);
1642 free(buf);
1643 return retval;
a5eda52b
DB
1644}
1645
70b9829e
DB
1646int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
1647 size_t bufsize, size_t *bufposn)
8237b185 1648{
230f1322 1649 char tmpfile[PATH_MAX];
8237b185
DB
1650 int local;
1651 z_stream stream;
1652 unsigned char real_sha1[20];
bf0f910d 1653 unsigned char discard[4096];
8237b185
DB
1654 int ret;
1655 SHA_CTX c;
1656
230f1322 1657 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
8237b185 1658
230f1322 1659 local = mkstemp(tmpfile);
8237b185 1660 if (local < 0)
bd2afde8
JH
1661 return error("Couldn't open %s for %s",
1662 tmpfile, sha1_to_hex(sha1));
8237b185
DB
1663
1664 memset(&stream, 0, sizeof(stream));
1665
1666 inflateInit(&stream);
1667
1668 SHA1_Init(&c);
1669
1670 do {
1671 ssize_t size;
70b9829e
DB
1672 if (*bufposn) {
1673 stream.avail_in = *bufposn;
96ad15ae 1674 stream.next_in = (unsigned char *) buffer;
70b9829e
DB
1675 do {
1676 stream.next_out = discard;
1677 stream.avail_out = sizeof(discard);
1678 ret = inflate(&stream, Z_SYNC_FLUSH);
1679 SHA1_Update(&c, discard, sizeof(discard) -
1680 stream.avail_out);
1681 } while (stream.avail_in && ret == Z_OK);
4d548150
LT
1682 if (write_buffer(local, buffer, *bufposn - stream.avail_in) < 0)
1683 die("unable to write sha1 file");
70b9829e
DB
1684 memmove(buffer, buffer + *bufposn - stream.avail_in,
1685 stream.avail_in);
1686 *bufposn = stream.avail_in;
1687 if (ret != Z_OK)
1688 break;
1689 }
1690 size = read(fd, buffer + *bufposn, bufsize - *bufposn);
8237b185
DB
1691 if (size <= 0) {
1692 close(local);
230f1322 1693 unlink(tmpfile);
8237b185
DB
1694 if (!size)
1695 return error("Connection closed?");
1696 perror("Reading from connection");
1697 return -1;
1698 }
70b9829e
DB
1699 *bufposn += size;
1700 } while (1);
8237b185
DB
1701 inflateEnd(&stream);
1702
1703 close(local);
1704 SHA1_Final(real_sha1, &c);
1705 if (ret != Z_STREAM_END) {
230f1322 1706 unlink(tmpfile);
8237b185
DB
1707 return error("File %s corrupted", sha1_to_hex(sha1));
1708 }
1709 if (memcmp(sha1, real_sha1, 20)) {
230f1322 1710 unlink(tmpfile);
bd2afde8 1711 return error("File %s has bad hash", sha1_to_hex(sha1));
8237b185 1712 }
230f1322
LT
1713
1714 return move_temp_to_file(tmpfile, sha1_file_name(sha1));
8237b185
DB
1715}
1716
bf592c50
DB
1717int has_pack_index(const unsigned char *sha1)
1718{
1719 struct stat st;
1720 if (stat(sha1_pack_index_name(sha1), &st))
1721 return 0;
1722 return 1;
1723}
1724
1725int has_pack_file(const unsigned char *sha1)
1726{
1727 struct stat st;
1728 if (stat(sha1_pack_name(sha1), &st))
1729 return 0;
1730 return 1;
1731}
1732
dade09c2
LT
1733int has_sha1_pack(const unsigned char *sha1)
1734{
1735 struct pack_entry e;
1736 return find_pack_entry(sha1, &e);
1737}
1738
8237b185
DB
1739int has_sha1_file(const unsigned char *sha1)
1740{
8237b185 1741 struct stat st;
1f688557
JH
1742 struct pack_entry e;
1743
ab90ea5d 1744 if (find_pack_entry(sha1, &e))
1f688557 1745 return 1;
ab90ea5d 1746 return find_sha1_file(sha1, &st) ? 1 : 0;
8237b185 1747}
74400e71 1748
e7332f96
BE
1749/*
1750 * reads from fd as long as possible into a supplied buffer of size bytes.
82e5a82f 1751 * If necessary the buffer's size is increased using realloc()
e7332f96
BE
1752 *
1753 * returns 0 if anything went fine and -1 otherwise
1754 *
1755 * NOTE: both buf and size may change, but even when -1 is returned
1756 * you still have to free() it yourself.
1757 */
1758int read_pipe(int fd, char** return_buf, unsigned long* return_size)
024510c8 1759{
e7332f96
BE
1760 char* buf = *return_buf;
1761 unsigned long size = *return_size;
1762 int iret;
024510c8 1763 unsigned long off = 0;
e7332f96 1764
024510c8 1765 do {
e7332f96 1766 iret = xread(fd, buf + off, size - off);
024510c8
DB
1767 if (iret > 0) {
1768 off += iret;
1769 if (off == size) {
1770 size *= 2;
1771 buf = realloc(buf, size);
1772 }
1773 }
1774 } while (iret > 0);
e7332f96
BE
1775
1776 *return_buf = buf;
1777 *return_size = off;
1778
1779 if (iret < 0)
1780 return -1;
1781 return 0;
1782}
1783
1784int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
1785{
1786 unsigned long size = 4096;
1787 char *buf = malloc(size);
1788 int ret;
1789 unsigned char hdr[50];
1790 int hdrlen;
1791
1792 if (read_pipe(fd, &buf, &size)) {
024510c8
DB
1793 free(buf);
1794 return -1;
1795 }
e7332f96 1796
024510c8 1797 if (!type)
8e440259 1798 type = blob_type;
024510c8 1799 if (write_object)
e7332f96 1800 ret = write_sha1_file(buf, size, type, sha1);
024510c8 1801 else {
e7332f96 1802 write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);
024510c8
DB
1803 ret = 0;
1804 }
1805 free(buf);
1806 return ret;
1807}
1808
7672db20 1809int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, const char *type)
74400e71 1810{
74400e71 1811 unsigned long size = st->st_size;
aac17941
LT
1812 void *buf;
1813 int ret;
7672db20
BL
1814 unsigned char hdr[50];
1815 int hdrlen;
74400e71 1816
aac17941 1817 buf = "";
74400e71 1818 if (size)
aac17941 1819 buf = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
74400e71 1820 close(fd);
e35f9824 1821 if (buf == MAP_FAILED)
74400e71
JH
1822 return -1;
1823
7672db20 1824 if (!type)
8e440259 1825 type = blob_type;
7672db20
BL
1826 if (write_object)
1827 ret = write_sha1_file(buf, size, type, sha1);
1828 else {
1829 write_sha1_file_prepare(buf, size, type, sha1, hdr, &hdrlen);
1830 ret = 0;
1831 }
aac17941
LT
1832 if (size)
1833 munmap(buf, size);
1834 return ret;
74400e71 1835}
ec1fcc16
JH
1836
1837int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
1838{
1839 int fd;
1840 char *target;
1841
1842 switch (st->st_mode & S_IFMT) {
1843 case S_IFREG:
1844 fd = open(path, O_RDONLY);
1845 if (fd < 0)
1846 return error("open(\"%s\"): %s", path,
1847 strerror(errno));
1848 if (index_fd(sha1, fd, st, write_object, NULL) < 0)
1849 return error("%s: failed to insert into database",
1850 path);
1851 break;
1852 case S_IFLNK:
1853 target = xmalloc(st->st_size+1);
1854 if (readlink(path, target, st->st_size+1) != st->st_size) {
1855 char *errstr = strerror(errno);
1856 free(target);
1857 return error("readlink(\"%s\"): %s", path,
1858 errstr);
1859 }
1860 if (!write_object) {
1861 unsigned char hdr[50];
1862 int hdrlen;
8e440259 1863 write_sha1_file_prepare(target, st->st_size, blob_type,
ec1fcc16 1864 sha1, hdr, &hdrlen);
8e440259 1865 } else if (write_sha1_file(target, st->st_size, blob_type, sha1))
ec1fcc16
JH
1866 return error("%s: failed to insert into database",
1867 path);
1868 free(target);
1869 break;
1870 default:
1871 return error("%s: unsupported file type", path);
1872 }
1873 return 0;
1874}