Display the null SHA-1 as the base for an OBJ_OFS_DELTA.
[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
e05db0fd
PR
25#ifdef NO_C99_FORMAT
26#define SZ_FMT "lu"
27#else
28#define SZ_FMT "zu"
29#endif
30
96f1e58f 31const unsigned char null_sha1[20];
88cd621d 32
144bde78
LT
33static unsigned int sha1_file_open_flag = O_NOATIME;
34
e49521b5
JH
35signed char hexval_table[256] = {
36 -1, -1, -1, -1, -1, -1, -1, -1, /* 00-07 */
37 -1, -1, -1, -1, -1, -1, -1, -1, /* 08-0f */
38 -1, -1, -1, -1, -1, -1, -1, -1, /* 10-17 */
39 -1, -1, -1, -1, -1, -1, -1, -1, /* 18-1f */
40 -1, -1, -1, -1, -1, -1, -1, -1, /* 20-27 */
41 -1, -1, -1, -1, -1, -1, -1, -1, /* 28-2f */
42 0, 1, 2, 3, 4, 5, 6, 7, /* 30-37 */
43 8, 9, -1, -1, -1, -1, -1, -1, /* 38-3f */
44 -1, 10, 11, 12, 13, 14, 15, -1, /* 40-47 */
45 -1, -1, -1, -1, -1, -1, -1, -1, /* 48-4f */
46 -1, -1, -1, -1, -1, -1, -1, -1, /* 50-57 */
47 -1, -1, -1, -1, -1, -1, -1, -1, /* 58-5f */
48 -1, 10, 11, 12, 13, 14, 15, -1, /* 60-67 */
49 -1, -1, -1, -1, -1, -1, -1, -1, /* 68-67 */
50 -1, -1, -1, -1, -1, -1, -1, -1, /* 70-77 */
51 -1, -1, -1, -1, -1, -1, -1, -1, /* 78-7f */
52 -1, -1, -1, -1, -1, -1, -1, -1, /* 80-87 */
53 -1, -1, -1, -1, -1, -1, -1, -1, /* 88-8f */
54 -1, -1, -1, -1, -1, -1, -1, -1, /* 90-97 */
55 -1, -1, -1, -1, -1, -1, -1, -1, /* 98-9f */
56 -1, -1, -1, -1, -1, -1, -1, -1, /* a0-a7 */
57 -1, -1, -1, -1, -1, -1, -1, -1, /* a8-af */
58 -1, -1, -1, -1, -1, -1, -1, -1, /* b0-b7 */
59 -1, -1, -1, -1, -1, -1, -1, -1, /* b8-bf */
60 -1, -1, -1, -1, -1, -1, -1, -1, /* c0-c7 */
61 -1, -1, -1, -1, -1, -1, -1, -1, /* c8-cf */
62 -1, -1, -1, -1, -1, -1, -1, -1, /* d0-d7 */
63 -1, -1, -1, -1, -1, -1, -1, -1, /* d8-df */
64 -1, -1, -1, -1, -1, -1, -1, -1, /* e0-e7 */
65 -1, -1, -1, -1, -1, -1, -1, -1, /* e8-ef */
66 -1, -1, -1, -1, -1, -1, -1, -1, /* f0-f7 */
67 -1, -1, -1, -1, -1, -1, -1, -1, /* f8-ff */
68};
0fcfd160
LT
69
70int get_sha1_hex(const char *hex, unsigned char *sha1)
71{
72 int i;
73 for (i = 0; i < 20; i++) {
74 unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
75 if (val & ~0xff)
76 return -1;
77 *sha1++ = val;
78 hex += 2;
79 }
80 return 0;
81}
82
b2cb9425
JH
83int safe_create_leading_directories(char *path)
84{
85 char *pos = path;
67d42212
JR
86 struct stat st;
87
67ffdf4c
JS
88 if (*pos == '/')
89 pos++;
b2cb9425
JH
90
91 while (pos) {
92 pos = strchr(pos, '/');
93 if (!pos)
94 break;
95 *pos = 0;
67d42212
JR
96 if (!stat(path, &st)) {
97 /* path exists */
98 if (!S_ISDIR(st.st_mode)) {
b2cb9425 99 *pos = '/';
67d42212 100 return -3;
b2cb9425 101 }
457f06d6 102 }
67d42212
JR
103 else if (mkdir(path, 0777)) {
104 *pos = '/';
105 return -1;
106 }
457f06d6
JS
107 else if (adjust_shared_perm(path)) {
108 *pos = '/';
109 return -2;
110 }
b2cb9425
JH
111 *pos++ = '/';
112 }
113 return 0;
114}
723c31fe 115
0fcfd160
LT
116char * sha1_to_hex(const unsigned char *sha1)
117{
dcb3450f
LT
118 static int bufno;
119 static char hexbuffer[4][50];
0fcfd160 120 static const char hex[] = "0123456789abcdef";
dcb3450f 121 char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
0fcfd160
LT
122 int i;
123
124 for (i = 0; i < 20; i++) {
125 unsigned int val = *sha1++;
126 *buf++ = hex[val >> 4];
127 *buf++ = hex[val & 0xf];
128 }
1e80e044
JS
129 *buf = '\0';
130
0fcfd160
LT
131 return buffer;
132}
133
ace1534d
JH
134static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
135{
136 int i;
137 for (i = 0; i < 20; i++) {
138 static char hex[] = "0123456789abcdef";
139 unsigned int val = sha1[i];
140 char *pos = pathbuf + i*2 + (i > 0);
141 *pos++ = hex[val >> 4];
142 *pos = hex[val & 0xf];
143 }
144}
145
0fcfd160
LT
146/*
147 * NOTE! This returns a statically allocated buffer, so you have to be
9befac47 148 * careful about using it. Do a "xstrdup()" if you need to save the
0fcfd160 149 * filename.
ace1534d
JH
150 *
151 * Also note that this returns the location for creating. Reading
152 * SHA1 file can happen from any alternate directory listed in the
d19938ab 153 * DB_ENVIRONMENT environment variable if it is not found in
ace1534d 154 * the primary object database.
0fcfd160
LT
155 */
156char *sha1_file_name(const unsigned char *sha1)
157{
0fcfd160
LT
158 static char *name, *base;
159
160 if (!base) {
d19938ab 161 const char *sha1_file_directory = get_object_directory();
0fcfd160 162 int len = strlen(sha1_file_directory);
812666c8 163 base = xmalloc(len + 60);
0fcfd160
LT
164 memcpy(base, sha1_file_directory, len);
165 memset(base+len, 0, 60);
166 base[len] = '/';
167 base[len+3] = '/';
168 name = base + len + 1;
169 }
ace1534d 170 fill_sha1_path(name, sha1);
0fcfd160
LT
171 return base;
172}
173
bf592c50
DB
174char *sha1_pack_name(const unsigned char *sha1)
175{
176 static const char hex[] = "0123456789abcdef";
177 static char *name, *base, *buf;
178 int i;
179
180 if (!base) {
181 const char *sha1_file_directory = get_object_directory();
182 int len = strlen(sha1_file_directory);
183 base = xmalloc(len + 60);
184 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
185 name = base + len + 11;
186 }
187
188 buf = name;
189
190 for (i = 0; i < 20; i++) {
191 unsigned int val = *sha1++;
192 *buf++ = hex[val >> 4];
193 *buf++ = hex[val & 0xf];
194 }
195
196 return base;
197}
198
199char *sha1_pack_index_name(const unsigned char *sha1)
200{
201 static const char hex[] = "0123456789abcdef";
202 static char *name, *base, *buf;
203 int i;
204
205 if (!base) {
206 const char *sha1_file_directory = get_object_directory();
207 int len = strlen(sha1_file_directory);
208 base = xmalloc(len + 60);
209 sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
210 name = base + len + 11;
211 }
212
213 buf = name;
214
215 for (i = 0; i < 20; i++) {
216 unsigned int val = *sha1++;
217 *buf++ = hex[val >> 4];
218 *buf++ = hex[val & 0xf];
219 }
220
221 return base;
222}
223
d5a63b99
JH
224struct alternate_object_database *alt_odb_list;
225static struct alternate_object_database **alt_odb_tail;
ace1534d 226
c2f493a4
MW
227static void read_info_alternates(const char * alternates, int depth);
228
ddd5d056
JH
229/*
230 * Prepare alternate object database registry.
d5a63b99
JH
231 *
232 * The variable alt_odb_list points at the list of struct
233 * alternate_object_database. The elements on this list come from
234 * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
235 * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
1494e038
JH
236 * whose contents is similar to that environment variable but can be
237 * LF separated. Its base points at a statically allocated buffer that
d5a63b99
JH
238 * contains "/the/directory/corresponding/to/.git/objects/...", while
239 * its name points just after the slash at the end of ".git/objects/"
240 * in the example above, and has enough space to hold 40-byte hex
241 * SHA1, an extra slash for the first level indirection, and the
242 * terminating NUL.
ddd5d056 243 */
c2f493a4 244static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
ace1534d 245{
c2f493a4 246 struct stat st;
1494e038 247 const char *objdir = get_object_directory();
c2f493a4
MW
248 struct alternate_object_database *ent;
249 struct alternate_object_database *alt;
250 /* 43 = 40-byte + 2 '/' + terminating NUL */
251 int pfxlen = len;
252 int entlen = pfxlen + 43;
ccfd3e99 253 int base_len = -1;
d5a63b99 254
c2f493a4
MW
255 if (*entry != '/' && relative_base) {
256 /* Relative alt-odb */
257 if (base_len < 0)
258 base_len = strlen(relative_base) + 1;
259 entlen += base_len;
260 pfxlen += base_len;
261 }
262 ent = xmalloc(sizeof(*ent) + entlen);
263
264 if (*entry != '/' && relative_base) {
265 memcpy(ent->base, relative_base, base_len - 1);
266 ent->base[base_len - 1] = '/';
267 memcpy(ent->base + base_len, entry, len);
268 }
269 else
270 memcpy(ent->base, entry, pfxlen);
271
272 ent->name = ent->base + pfxlen + 1;
273 ent->base[pfxlen + 3] = '/';
274 ent->base[pfxlen] = ent->base[entlen-1] = 0;
275
276 /* Detect cases where alternate disappeared */
277 if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
278 error("object directory %s does not exist; "
279 "check .git/objects/info/alternates.",
280 ent->base);
281 free(ent);
282 return -1;
283 }
284
285 /* Prevent the common mistake of listing the same
286 * thing twice, or object directory itself.
287 */
288 for (alt = alt_odb_list; alt; alt = alt->next) {
289 if (!memcmp(ent->base, alt->base, pfxlen)) {
290 free(ent);
291 return -1;
292 }
293 }
294 if (!memcmp(ent->base, objdir, pfxlen)) {
295 free(ent);
296 return -1;
297 }
298
299 /* add the alternate entry */
300 *alt_odb_tail = ent;
301 alt_odb_tail = &(ent->next);
302 ent->next = NULL;
303
304 /* recursively add alternates */
305 read_info_alternates(ent->base, depth + 1);
306
307 ent->base[pfxlen] = '/';
308
309 return 0;
310}
311
312static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
313 const char *relative_base, int depth)
314{
315 const char *cp, *last;
316
317 if (depth > 5) {
318 error("%s: ignoring alternate object stores, nesting too deep.",
319 relative_base);
320 return;
321 }
322
d5a63b99 323 last = alt;
9577e7e3
JH
324 while (last < ep) {
325 cp = last;
326 if (cp < ep && *cp == '#') {
327 while (cp < ep && *cp != sep)
328 cp++;
329 last = cp + 1;
330 continue;
331 }
c2f493a4
MW
332 while (cp < ep && *cp != sep)
333 cp++;
d5a63b99 334 if (last != cp) {
c2f493a4
MW
335 if ((*last != '/') && depth) {
336 error("%s: ignoring relative alternate object store %s",
337 relative_base, last);
338 } else {
339 link_alt_odb_entry(last, cp - last,
340 relative_base, depth);
1494e038 341 }
d5a63b99 342 }
9577e7e3 343 while (cp < ep && *cp == sep)
d5a63b99
JH
344 cp++;
345 last = cp;
9577e7e3 346 }
d5a63b99
JH
347}
348
c2f493a4 349static void read_info_alternates(const char * relative_base, int depth)
d5a63b99 350{
9577e7e3 351 char *map;
d5a63b99 352 struct stat st;
c2f493a4
MW
353 char path[PATH_MAX];
354 int fd;
d5a63b99 355
c2f493a4 356 sprintf(path, "%s/info/alternates", relative_base);
d5a63b99
JH
357 fd = open(path, O_RDONLY);
358 if (fd < 0)
359 return;
360 if (fstat(fd, &st) || (st.st_size == 0)) {
361 close(fd);
9a217f2a 362 return;
ace1534d 363 }
c4712e45 364 map = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
d5a63b99 365 close(fd);
d5a63b99 366
c2f493a4
MW
367 link_alt_odb_entries(map, map + st.st_size, '\n', relative_base, depth);
368
d5a63b99 369 munmap(map, st.st_size);
ace1534d
JH
370}
371
c2f493a4
MW
372void prepare_alt_odb(void)
373{
554fe20d 374 const char *alt;
c2f493a4
MW
375
376 alt = getenv(ALTERNATE_DB_ENVIRONMENT);
377 if (!alt) alt = "";
378
379 if (alt_odb_tail)
380 return;
381 alt_odb_tail = &alt_odb_list;
382 link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL, 0);
383
384 read_info_alternates(get_object_directory(), 0);
385}
386
ace1534d
JH
387static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
388{
ace1534d 389 char *name = sha1_file_name(sha1);
d5a63b99 390 struct alternate_object_database *alt;
ace1534d
JH
391
392 if (!stat(name, st))
393 return name;
9a217f2a 394 prepare_alt_odb();
d5a63b99
JH
395 for (alt = alt_odb_list; alt; alt = alt->next) {
396 name = alt->name;
ace1534d 397 fill_sha1_path(name, sha1);
d5a63b99
JH
398 if (!stat(alt->base, st))
399 return alt->base;
ace1534d
JH
400 }
401 return NULL;
402}
403
60bb8b14 404static unsigned int pack_used_ctr;
a53128b6
SP
405static unsigned int pack_mmap_calls;
406static unsigned int peak_pack_open_windows;
407static unsigned int pack_open_windows;
408static size_t peak_pack_mapped;
60bb8b14 409static size_t pack_mapped;
9a217f2a 410struct packed_git *packed_git;
1f688557 411
a53128b6
SP
412void pack_report()
413{
414 fprintf(stderr,
e05db0fd
PR
415 "pack_report: getpagesize() = %10" SZ_FMT "\n"
416 "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
417 "pack_report: core.packedGitLimit = %10" SZ_FMT "\n",
78a28df9 418 (size_t) getpagesize(),
a53128b6
SP
419 packed_git_window_size,
420 packed_git_limit);
421 fprintf(stderr,
422 "pack_report: pack_used_ctr = %10u\n"
423 "pack_report: pack_mmap_calls = %10u\n"
424 "pack_report: pack_open_windows = %10u / %10u\n"
e05db0fd
PR
425 "pack_report: pack_mapped = "
426 "%10" SZ_FMT " / %10" SZ_FMT "\n",
a53128b6
SP
427 pack_used_ctr,
428 pack_mmap_calls,
429 pack_open_windows, peak_pack_open_windows,
430 pack_mapped, peak_pack_mapped);
431}
432
1f688557
JH
433static int check_packed_git_idx(const char *path, unsigned long *idx_size_,
434 void **idx_map_)
435{
436 void *idx_map;
b18b00a6 437 uint32_t *index;
1f688557
JH
438 unsigned long idx_size;
439 int nr, i;
e93ec6f9 440 int fd = open(path, O_RDONLY);
1f688557
JH
441 struct stat st;
442 if (fd < 0)
443 return -1;
444 if (fstat(fd, &st)) {
445 close(fd);
446 return -1;
447 }
448 idx_size = st.st_size;
c4712e45 449 idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
1f688557 450 close(fd);
1f688557
JH
451
452 index = idx_map;
4d235c80
LT
453 *idx_map_ = idx_map;
454 *idx_size_ = idx_size;
1f688557
JH
455
456 /* check index map */
f9253394 457 if (idx_size < 4*256 + 20 + 20)
df1b059d
SP
458 return error("index file %s is too small", path);
459
460 /* a future index format would start with this, as older git
461 * binaries would fail the non-monotonic index check below.
462 * give a nicer warning to the user if we can.
463 */
464 if (index[0] == htonl(PACK_IDX_SIGNATURE))
465 return error("index file %s is a newer version"
466 " and is not supported by this binary"
467 " (try upgrading GIT to a newer version)",
468 path);
469
1f688557
JH
470 nr = 0;
471 for (i = 0; i < 256; i++) {
472 unsigned int n = ntohl(index[i]);
473 if (n < nr)
df1b059d 474 return error("non-monotonic index %s", path);
1f688557
JH
475 nr = n;
476 }
477
478 /*
479 * Total size:
480 * - 256 index entries 4 bytes each
481 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
482 * - 20-byte SHA1 of the packfile
483 * - 20-byte SHA1 file checksum
484 */
485 if (idx_size != 4*256 + nr * 24 + 20 + 20)
df1b059d 486 return error("wrong index file size in %s", path);
1f688557 487
1f688557
JH
488 return 0;
489}
490
11daf39b
SP
491static void scan_windows(struct packed_git *p,
492 struct packed_git **lru_p,
493 struct pack_window **lru_w,
494 struct pack_window **lru_l)
1f688557 495{
11daf39b
SP
496 struct pack_window *w, *w_l;
497
498 for (w_l = NULL, w = p->windows; w; w = w->next) {
499 if (!w->inuse_cnt) {
500 if (!*lru_w || w->last_used < (*lru_w)->last_used) {
501 *lru_p = p;
502 *lru_w = w;
503 *lru_l = w_l;
54044bf8 504 }
54044bf8 505 }
11daf39b 506 w_l = w;
f9253394 507 }
11daf39b
SP
508}
509
510static int unuse_one_window(struct packed_git *current)
511{
512 struct packed_git *p, *lru_p = NULL;
513 struct pack_window *lru_w = NULL, *lru_l = NULL;
514
515 if (current)
516 scan_windows(current, &lru_p, &lru_w, &lru_l);
517 for (p = packed_git; p; p = p->next)
518 scan_windows(p, &lru_p, &lru_w, &lru_l);
54044bf8
SP
519 if (lru_p) {
520 munmap(lru_w->base, lru_w->len);
521 pack_mapped -= lru_w->len;
522 if (lru_l)
523 lru_l->next = lru_w->next;
524 else {
525 lru_p->windows = lru_w->next;
11daf39b 526 if (!lru_p->windows && lru_p != current) {
54044bf8
SP
527 close(lru_p->pack_fd);
528 lru_p->pack_fd = -1;
529 }
530 }
531 free(lru_w);
a53128b6 532 pack_open_windows--;
54044bf8
SP
533 return 1;
534 }
535 return 0;
f9253394
JH
536}
537
97bfeb34
SP
538void release_pack_memory(size_t need)
539{
540 size_t cur = pack_mapped;
541 while (need >= (cur - pack_mapped) && unuse_one_window(NULL))
542 ; /* nothing */
543}
544
03e79c88 545void unuse_pack(struct pack_window **w_cursor)
f9253394 546{
03e79c88
SP
547 struct pack_window *w = *w_cursor;
548 if (w) {
549 w->inuse_cnt--;
550 *w_cursor = NULL;
551 }
1f688557
JH
552}
553
3cf8b462
SP
554/*
555 * Do not call this directly as this leaks p->pack_fd on error return;
556 * call open_packed_git() instead.
557 */
558static int open_packed_git_1(struct packed_git *p)
1f688557 559{
9bc879c1
SP
560 struct stat st;
561 struct pack_header hdr;
562 unsigned char sha1[20];
563 unsigned char *idx_sha1;
2c039da8 564 long fd_flag;
9bc879c1
SP
565
566 p->pack_fd = open(p->pack_name, O_RDONLY);
567 if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
072db278 568 return -1;
9bc879c1
SP
569
570 /* If we created the struct before we had the pack we lack size. */
bf592c50 571 if (!p->pack_size) {
bf592c50 572 if (!S_ISREG(st.st_mode))
072db278 573 return error("packfile %s not a regular file", p->pack_name);
bf592c50 574 p->pack_size = st.st_size;
9bc879c1 575 } else if (p->pack_size != st.st_size)
072db278 576 return error("packfile %s size changed", p->pack_name);
9bc879c1 577
2c039da8
JH
578 /* We leave these file descriptors open with sliding mmap;
579 * there is no point keeping them open across exec(), though.
580 */
581 fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
582 if (fd_flag < 0)
072db278 583 return error("cannot determine file descriptor flags");
2c039da8
JH
584 fd_flag |= FD_CLOEXEC;
585 if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
072db278 586 return error("cannot set FD_CLOEXEC");
2c039da8 587
9bc879c1 588 /* Verify we recognize this pack file format. */
e6e2bd62 589 if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
072db278 590 return error("file %s is far too short to be a packfile", p->pack_name);
9bc879c1 591 if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
072db278 592 return error("file %s is not a GIT packfile", p->pack_name);
9bc879c1 593 if (!pack_version_ok(hdr.hdr_version))
072db278 594 return error("packfile %s is version %u and not supported"
9bc879c1
SP
595 " (try upgrading GIT to a newer version)",
596 p->pack_name, ntohl(hdr.hdr_version));
597
598 /* Verify the pack matches its index. */
599 if (num_packed_objects(p) != ntohl(hdr.hdr_entries))
072db278 600 return error("packfile %s claims to have %u objects"
9bc879c1
SP
601 " while index size indicates %u objects",
602 p->pack_name, ntohl(hdr.hdr_entries),
603 num_packed_objects(p));
604 if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
072db278 605 return error("end of packfile %s is unavailable", p->pack_name);
e6e2bd62 606 if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
072db278 607 return error("packfile %s signature is unavailable", p->pack_name);
9bc879c1
SP
608 idx_sha1 = ((unsigned char *)p->index_base) + p->index_size - 40;
609 if (hashcmp(sha1, idx_sha1))
072db278
SP
610 return error("packfile %s does not match index", p->pack_name);
611 return 0;
9bc879c1
SP
612}
613
3cf8b462
SP
614static int open_packed_git(struct packed_git *p)
615{
616 if (!open_packed_git_1(p))
617 return 0;
618 if (p->pack_fd != -1) {
619 close(p->pack_fd);
620 p->pack_fd = -1;
621 }
622 return -1;
623}
624
60bb8b14
SP
625static int in_window(struct pack_window *win, unsigned long offset)
626{
627 /* We must promise at least 20 bytes (one hash) after the
628 * offset is available from this window, otherwise the offset
629 * is not actually in this window and a different window (which
630 * has that one hash excess) must be used. This is to support
631 * the object header and delta base parsing routines below.
632 */
633 off_t win_off = win->offset;
634 return win_off <= offset
635 && (offset + 20) <= (win_off + win->len);
636}
637
03e79c88
SP
638unsigned char* use_pack(struct packed_git *p,
639 struct pack_window **w_cursor,
640 unsigned long offset,
641 unsigned int *left)
9bc879c1 642{
60bb8b14 643 struct pack_window *win = *w_cursor;
03e79c88 644
072db278
SP
645 if (p->pack_fd == -1 && open_packed_git(p))
646 die("packfile %s cannot be accessed", p->pack_name);
60bb8b14
SP
647
648 /* Since packfiles end in a hash of their content and its
649 * pointless to ask for an offset into the middle of that
650 * hash, and the in_window function above wouldn't match
651 * don't allow an offset too close to the end of the file.
652 */
653 if (offset > (p->pack_size - 20))
654 die("offset beyond end of packfile (truncated pack?)");
655
656 if (!win || !in_window(win, offset)) {
657 if (win)
658 win->inuse_cnt--;
659 for (win = p->windows; win; win = win->next) {
660 if (in_window(win, offset))
661 break;
662 }
663 if (!win) {
78a28df9 664 size_t window_align = packed_git_window_size / 2;
60bb8b14 665 win = xcalloc(1, sizeof(*win));
78a28df9 666 win->offset = (offset / window_align) * window_align;
60bb8b14
SP
667 win->len = p->pack_size - win->offset;
668 if (win->len > packed_git_window_size)
669 win->len = packed_git_window_size;
670 pack_mapped += win->len;
11daf39b
SP
671 while (packed_git_limit < pack_mapped
672 && unuse_one_window(p))
60bb8b14 673 ; /* nothing */
c4712e45 674 win->base = xmmap(NULL, win->len,
60bb8b14
SP
675 PROT_READ, MAP_PRIVATE,
676 p->pack_fd, win->offset);
677 if (win->base == MAP_FAILED)
73b4e4be
SP
678 die("packfile %s cannot be mapped: %s",
679 p->pack_name,
680 strerror(errno));
a53128b6
SP
681 pack_mmap_calls++;
682 pack_open_windows++;
683 if (pack_mapped > peak_pack_mapped)
684 peak_pack_mapped = pack_mapped;
685 if (pack_open_windows > peak_pack_open_windows)
686 peak_pack_open_windows = pack_open_windows;
60bb8b14
SP
687 win->next = p->windows;
688 p->windows = win;
689 }
1f688557 690 }
03e79c88
SP
691 if (win != *w_cursor) {
692 win->last_used = pack_used_ctr++;
693 win->inuse_cnt++;
694 *w_cursor = win;
695 }
60bb8b14 696 offset -= win->offset;
03e79c88
SP
697 if (left)
698 *left = win->len - offset;
699 return win->base + offset;
1f688557
JH
700}
701
9d835df2 702struct packed_git *add_packed_git(char *path, int path_len, int local)
1f688557
JH
703{
704 struct stat st;
705 struct packed_git *p;
706 unsigned long idx_size;
707 void *idx_map;
c0bbbb1b 708 unsigned char sha1[20];
1f688557
JH
709
710 if (check_packed_git_idx(path, &idx_size, &idx_map))
711 return NULL;
712
713 /* do we have a corresponding .pack file? */
714 strcpy(path + path_len - 4, ".pack");
715 if (stat(path, &st) || !S_ISREG(st.st_mode)) {
716 munmap(idx_map, idx_size);
717 return NULL;
718 }
719 /* ok, it looks sane as far as we can check without
720 * actually mapping the pack file.
721 */
722 p = xmalloc(sizeof(*p) + path_len + 2);
723 strcpy(p->pack_name, path);
724 p->index_size = idx_size;
725 p->pack_size = st.st_size;
726 p->index_base = idx_map;
727 p->next = NULL;
c41ee586 728 p->windows = NULL;
9bc879c1 729 p->pack_fd = -1;
9d835df2 730 p->pack_local = local;
f4a11066 731 if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
e702496e 732 hashcpy(p->sha1, sha1);
1f688557
JH
733 return p;
734}
735
bf592c50 736struct packed_git *parse_pack_index(unsigned char *sha1)
c508df5e
DB
737{
738 char *path = sha1_pack_index_name(sha1);
739 return parse_pack_index_file(sha1, path);
740}
741
2ab141a2 742struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path)
bf592c50
DB
743{
744 struct packed_git *p;
745 unsigned long idx_size;
746 void *idx_map;
c508df5e 747 char *path;
bf592c50 748
c508df5e 749 if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
bf592c50
DB
750 return NULL;
751
752 path = sha1_pack_name(sha1);
753
754 p = xmalloc(sizeof(*p) + strlen(path) + 2);
755 strcpy(p->pack_name, path);
756 p->index_size = idx_size;
757 p->pack_size = 0;
758 p->index_base = idx_map;
759 p->next = NULL;
c41ee586 760 p->windows = NULL;
9bc879c1 761 p->pack_fd = -1;
e702496e 762 hashcpy(p->sha1, sha1);
bf592c50
DB
763 return p;
764}
765
766void install_packed_git(struct packed_git *pack)
767{
768 pack->next = packed_git;
769 packed_git = pack;
770}
771
9d835df2 772static void prepare_packed_git_one(char *objdir, int local)
1f688557
JH
773{
774 char path[PATH_MAX];
775 int len;
776 DIR *dir;
777 struct dirent *de;
778
779 sprintf(path, "%s/pack", objdir);
780 len = strlen(path);
781 dir = opendir(path);
b5b16990 782 if (!dir) {
26125f6b 783 if (errno != ENOENT)
bd2afde8 784 error("unable to open object pack directory: %s: %s",
26125f6b 785 path, strerror(errno));
1f688557 786 return;
b5b16990 787 }
1f688557
JH
788 path[len++] = '/';
789 while ((de = readdir(dir)) != NULL) {
790 int namelen = strlen(de->d_name);
791 struct packed_git *p;
792
5bb1cda5 793 if (!has_extension(de->d_name, ".idx"))
1f688557
JH
794 continue;
795
54a15a8d 796 /* Don't reopen a pack we already have. */
1f688557 797 strcpy(path + len, de->d_name);
86f7780c
JK
798 for (p = packed_git; p; p = p->next) {
799 if (!memcmp(path, p->pack_name, len + namelen - 4))
800 break;
801 }
802 if (p)
803 continue;
54a15a8d
SP
804 /* See if it really is a valid .idx file with corresponding
805 * .pack file that we can map.
806 */
9d835df2 807 p = add_packed_git(path, len + namelen, local);
1f688557
JH
808 if (!p)
809 continue;
625e9421 810 install_packed_git(p);
1f688557 811 }
5b35bcd5 812 closedir(dir);
1f688557
JH
813}
814
637cdd9d 815static int prepare_packed_git_run_once = 0;
9a217f2a 816void prepare_packed_git(void)
1f688557 817{
d5a63b99 818 struct alternate_object_database *alt;
1f688557 819
637cdd9d 820 if (prepare_packed_git_run_once)
1f688557 821 return;
9d835df2 822 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 823 prepare_alt_odb();
d5a63b99 824 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 825 alt->name[-1] = 0;
9d835df2 826 prepare_packed_git_one(alt->base, 0);
1494e038 827 alt->name[-1] = '/';
1f688557 828 }
637cdd9d
JK
829 prepare_packed_git_run_once = 1;
830}
831
fc04c412 832void reprepare_packed_git(void)
637cdd9d
JK
833{
834 prepare_packed_git_run_once = 0;
835 prepare_packed_git();
1f688557
JH
836}
837
5d6ccf5c 838int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
0fcfd160
LT
839{
840 unsigned char real_sha1[20];
7cfb5f36 841 hash_sha1_file(map, size, type, real_sha1);
a89fccd2 842 return hashcmp(sha1, real_sha1) ? -1 : 0;
0fcfd160
LT
843}
844
bb6b8e4f 845void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
0fcfd160 846{
0fcfd160
LT
847 struct stat st;
848 void *map;
144bde78 849 int fd;
ace1534d
JH
850 char *filename = find_sha1_file(sha1, &st);
851
852 if (!filename) {
ace1534d
JH
853 return NULL;
854 }
0fcfd160 855
144bde78 856 fd = open(filename, O_RDONLY | sha1_file_open_flag);
0fcfd160 857 if (fd < 0) {
144bde78
LT
858 /* See if it works without O_NOATIME */
859 switch (sha1_file_open_flag) {
860 default:
861 fd = open(filename, O_RDONLY);
862 if (fd >= 0)
863 break;
864 /* Fallthrough */
865 case 0:
144bde78
LT
866 return NULL;
867 }
868
1f688557
JH
869 /* If it failed once, it will probably fail again.
870 * Stop using O_NOATIME
871 */
144bde78 872 sha1_file_open_flag = 0;
0fcfd160 873 }
c4712e45 874 map = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
0fcfd160 875 close(fd);
0fcfd160
LT
876 *size = st.st_size;
877 return map;
878}
879
bb6b8e4f
JH
880int legacy_loose_object(unsigned char *map)
881{
882 unsigned int word;
883
884 /*
885 * Is it a zlib-compressed buffer? If so, the first byte
886 * must be 0x78 (15-bit window size, deflated), and the
887 * first 16-bit word is evenly divisible by 31
888 */
889 word = (map[0] << 8) + map[1];
890 if (map[0] == 0x78 && !(word % 31))
891 return 1;
892 else
893 return 0;
894}
895
72518e9c 896unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep)
c4483576 897{
ad1ed5ee 898 unsigned shift;
93821bd9 899 unsigned char c;
93821bd9 900 unsigned long size;
ad1ed5ee
JH
901 unsigned long used = 0;
902
903 c = buf[used++];
904 *type = (c >> 4) & 7;
905 size = c & 15;
906 shift = 4;
907 while (c & 0x80) {
908 if (len <= used)
909 return 0;
910 if (sizeof(long) * 8 <= shift)
911 return 0;
912 c = buf[used++];
913 size += (c & 0x7f) << shift;
914 shift += 7;
915 }
916 *sizep = size;
917 return used;
918}
919
920static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
921{
922 unsigned long size, used;
923 static const char valid_loose_object_type[8] = {
924 0, /* OBJ_EXT */
925 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
926 0, /* "delta" and others are invalid in a loose object */
93821bd9 927 };
ad1ed5ee 928 enum object_type type;
93821bd9 929
c4483576
LT
930 /* Get the data stream */
931 memset(stream, 0, sizeof(*stream));
932 stream->next_in = map;
933 stream->avail_in = mapsize;
934 stream->next_out = buffer;
93821bd9
LT
935 stream->avail_out = bufsiz;
936
bb6b8e4f 937 if (legacy_loose_object(map)) {
93821bd9
LT
938 inflateInit(stream);
939 return inflate(stream, 0);
940 }
941
ad1ed5ee
JH
942 used = unpack_object_header_gently(map, mapsize, &type, &size);
943 if (!used || !valid_loose_object_type[type])
93821bd9 944 return -1;
ad1ed5ee
JH
945 map += used;
946 mapsize -= used;
93821bd9
LT
947
948 /* Set up the stream for the rest.. */
949 stream->next_in = map;
950 stream->avail_in = mapsize;
c4483576 951 inflateInit(stream);
93821bd9
LT
952
953 /* And generate the fake traditional header */
ad1ed5ee 954 stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
df843662 955 typename(type), size);
93821bd9 956 return 0;
c4483576
LT
957}
958
6da4016a 959static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
5180cacc
LT
960{
961 int bytes = strlen(buffer) + 1;
d565b341 962 unsigned char *buf = xmalloc(1+size);
93821bd9 963 unsigned long n;
5180cacc 964
93821bd9
LT
965 n = stream->total_out - bytes;
966 if (n > size)
967 n = size;
968 memcpy(buf, (char *) buffer + bytes, n);
969 bytes = n;
5180cacc
LT
970 if (bytes < size) {
971 stream->next_out = buf + bytes;
972 stream->avail_out = size - bytes;
973 while (inflate(stream, Z_FINISH) == Z_OK)
974 /* nothing */;
975 }
976 buf[size] = 0;
977 inflateEnd(stream);
978 return buf;
979}
980
981/*
982 * We used to just use "sscanf()", but that's actually way
983 * too permissive for what we want to check. So do an anal
984 * object header parse by hand.
985 */
21666f1a 986static int parse_sha1_header(const char *hdr, unsigned long *sizep)
5180cacc 987{
21666f1a 988 char type[10];
5180cacc
LT
989 int i;
990 unsigned long size;
991
992 /*
993 * The type can be at most ten bytes (including the
994 * terminating '\0' that we add), and is followed by
21666f1a 995 * a space.
5180cacc 996 */
21666f1a 997 i = 0;
5180cacc
LT
998 for (;;) {
999 char c = *hdr++;
1000 if (c == ' ')
1001 break;
21666f1a
NP
1002 type[i++] = c;
1003 if (i >= sizeof(type))
5180cacc 1004 return -1;
5180cacc 1005 }
21666f1a 1006 type[i] = 0;
5180cacc
LT
1007
1008 /*
1009 * The length must follow immediately, and be in canonical
1010 * decimal format (ie "010" is not valid).
1011 */
1012 size = *hdr++ - '0';
1013 if (size > 9)
1014 return -1;
1015 if (size) {
1016 for (;;) {
1017 unsigned long c = *hdr - '0';
1018 if (c > 9)
1019 break;
1020 hdr++;
1021 size = size * 10 + c;
1022 }
1023 }
1024 *sizep = size;
1025
1026 /*
1027 * The length must be followed by a zero byte
1028 */
21666f1a 1029 return *hdr ? -1 : type_from_string(type);
5180cacc
LT
1030}
1031
21666f1a 1032void * unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size)
0fcfd160 1033{
5180cacc 1034 int ret;
0fcfd160 1035 z_stream stream;
5180cacc 1036 char hdr[8192];
0fcfd160 1037
5180cacc 1038 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
21666f1a 1039 if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
0fcfd160
LT
1040 return NULL;
1041
5180cacc 1042 return unpack_sha1_rest(&stream, hdr, *size);
0fcfd160
LT
1043}
1044
eb32d236 1045static unsigned long get_delta_base(struct packed_git *p,
03e79c88 1046 struct pack_window **w_curs,
2b87c45b 1047 unsigned long *curpos,
21666f1a 1048 enum object_type type,
2b87c45b 1049 unsigned long delta_obj_offset)
eb32d236 1050{
2b87c45b 1051 unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
eb32d236
NP
1052 unsigned long base_offset;
1053
8d8a4ea5
SP
1054 /* use_pack() assured us we have [base_info, base_info + 20)
1055 * as a range that we can look at without walking off the
1056 * end of the mapped window. Its actually the hash size
1057 * that is assured. An OFS_DELTA longer than the hash size
1058 * is stupid, as then a REF_DELTA would be smaller to store.
1059 */
21666f1a 1060 if (type == OBJ_OFS_DELTA) {
eb32d236
NP
1061 unsigned used = 0;
1062 unsigned char c = base_info[used++];
1063 base_offset = c & 127;
1064 while (c & 128) {
1065 base_offset += 1;
1066 if (!base_offset || base_offset & ~(~0UL >> 7))
1067 die("offset value overflow for delta base object");
1068 c = base_info[used++];
1069 base_offset = (base_offset << 7) + (c & 127);
1070 }
1071 base_offset = delta_obj_offset - base_offset;
1072 if (base_offset >= delta_obj_offset)
1073 die("delta base offset out of bound");
2b87c45b 1074 *curpos += used;
21666f1a 1075 } else if (type == OBJ_REF_DELTA) {
eb32d236
NP
1076 /* The base entry _must_ be in the same pack */
1077 base_offset = find_pack_entry_one(base_info, p);
1078 if (!base_offset)
1079 die("failed to find delta-pack base object %s",
1080 sha1_to_hex(base_info));
2b87c45b 1081 *curpos += 20;
eb32d236
NP
1082 } else
1083 die("I am totally screwed");
2b87c45b 1084 return base_offset;
eb32d236
NP
1085}
1086
f3bf9224 1087/* forward declaration for a mutually recursive function */
43057304 1088static int packed_object_info(struct packed_git *p, unsigned long offset,
21666f1a 1089 unsigned long *sizep);
f3bf9224 1090
43057304 1091static int packed_delta_info(struct packed_git *p,
03e79c88 1092 struct pack_window **w_curs,
2b87c45b 1093 unsigned long curpos,
21666f1a 1094 enum object_type type,
eb32d236 1095 unsigned long obj_offset,
43057304 1096 unsigned long *sizep)
5db47c2b 1097{
43057304 1098 unsigned long base_offset;
f3bf9224 1099
21666f1a
NP
1100 base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
1101 type = packed_object_info(p, base_offset, NULL);
f3bf9224 1102
c62266f3
JH
1103 /* We choose to only get the type of the base object and
1104 * ignore potentially corrupt pack file that expects the delta
1105 * based on a base with a wrong size. This saves tons of
1106 * inflate() calls.
1107 */
c62266f3
JH
1108 if (sizep) {
1109 const unsigned char *data;
079afb18 1110 unsigned char delta_head[20], *in;
c62266f3
JH
1111 z_stream stream;
1112 int st;
1113
1114 memset(&stream, 0, sizeof(stream));
c62266f3
JH
1115 stream.next_out = delta_head;
1116 stream.avail_out = sizeof(delta_head);
1117
1118 inflateInit(&stream);
079afb18 1119 do {
2b87c45b 1120 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18
SP
1121 stream.next_in = in;
1122 st = inflate(&stream, Z_FINISH);
2b87c45b 1123 curpos += stream.next_in - in;
079afb18
SP
1124 } while ((st == Z_OK || st == Z_BUF_ERROR)
1125 && stream.total_out < sizeof(delta_head));
c62266f3
JH
1126 inflateEnd(&stream);
1127 if ((st != Z_STREAM_END) &&
1128 stream.total_out != sizeof(delta_head))
1129 die("delta data unpack-initial failed");
1130
1131 /* Examine the initial part of the delta to figure out
1132 * the result size.
1133 */
1134 data = delta_head;
8960844a
NP
1135
1136 /* ignore base size */
1137 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
5db47c2b 1138
c62266f3 1139 /* Read the result size */
2b87c45b 1140 *sizep = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
c62266f3 1141 }
21666f1a
NP
1142
1143 return type;
5db47c2b
JH
1144}
1145
2b87c45b
NP
1146static int unpack_object_header(struct packed_git *p,
1147 struct pack_window **w_curs,
1148 unsigned long *curpos,
1149 unsigned long *sizep)
a733cb60 1150{
03e79c88
SP
1151 unsigned char *base;
1152 unsigned int left;
ad1ed5ee 1153 unsigned long used;
2b87c45b 1154 enum object_type type;
a733cb60 1155
8d8a4ea5
SP
1156 /* use_pack() assures us we have [base, base + 20) available
1157 * as a range that we can look at at. (Its actually the hash
3dff5379 1158 * size that is assured.) With our object header encoding
8d8a4ea5
SP
1159 * the maximum deflated object size is 2^137, which is just
1160 * insane, so we know won't exceed what we have been given.
1161 */
2b87c45b
NP
1162 base = use_pack(p, w_curs, *curpos, &left);
1163 used = unpack_object_header_gently(base, left, &type, sizep);
ad1ed5ee
JH
1164 if (!used)
1165 die("object offset outside of pack file");
2b87c45b 1166 *curpos += used;
ad1ed5ee 1167
2b87c45b 1168 return type;
a733cb60
LT
1169}
1170
21666f1a
NP
1171const char *packed_object_info_detail(struct packed_git *p,
1172 unsigned long obj_offset,
1173 unsigned long *size,
1174 unsigned long *store_size,
1175 unsigned int *delta_chain_length,
1176 unsigned char *base_sha1)
ad8c80a5 1177{
03e79c88 1178 struct pack_window *w_curs = NULL;
2b87c45b 1179 unsigned long curpos, dummy;
43057304 1180 unsigned char *next_sha1;
21666f1a 1181 enum object_type type;
ad8c80a5 1182
43057304 1183 *delta_chain_length = 0;
2b87c45b 1184 curpos = obj_offset;
21666f1a 1185 type = unpack_object_header(p, &w_curs, &curpos, size);
43057304
NP
1186
1187 for (;;) {
21666f1a 1188 switch (type) {
43057304 1189 default:
08a19d87 1190 die("pack %s contains unknown object type %d",
21666f1a 1191 p->pack_name, type);
43057304
NP
1192 case OBJ_COMMIT:
1193 case OBJ_TREE:
1194 case OBJ_BLOB:
1195 case OBJ_TAG:
43057304 1196 *store_size = 0; /* notyet */
03e79c88 1197 unuse_pack(&w_curs);
21666f1a 1198 return typename(type);
eb32d236 1199 case OBJ_OFS_DELTA:
21666f1a 1200 obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
eb32d236 1201 if (*delta_chain_length == 0) {
2b87c45b 1202 /* TODO: find base_sha1 as pointed by curpos */
30fee062 1203 hashclr(base_sha1);
eb32d236
NP
1204 }
1205 break;
1206 case OBJ_REF_DELTA:
2b87c45b 1207 next_sha1 = use_pack(p, &w_curs, curpos, NULL);
43057304
NP
1208 if (*delta_chain_length == 0)
1209 hashcpy(base_sha1, next_sha1);
2b87c45b 1210 obj_offset = find_pack_entry_one(next_sha1, p);
43057304
NP
1211 break;
1212 }
43057304 1213 (*delta_chain_length)++;
2b87c45b 1214 curpos = obj_offset;
21666f1a 1215 type = unpack_object_header(p, &w_curs, &curpos, &dummy);
ad8c80a5 1216 }
ad8c80a5
JH
1217}
1218
2b87c45b 1219static int packed_object_info(struct packed_git *p, unsigned long obj_offset,
21666f1a 1220 unsigned long *sizep)
1f688557 1221{
03e79c88 1222 struct pack_window *w_curs = NULL;
2b87c45b 1223 unsigned long size, curpos = obj_offset;
21666f1a 1224 enum object_type type;
5db47c2b 1225
21666f1a 1226 type = unpack_object_header(p, &w_curs, &curpos, &size);
5db47c2b 1227
21666f1a 1228 switch (type) {
eb32d236
NP
1229 case OBJ_OFS_DELTA:
1230 case OBJ_REF_DELTA:
21666f1a
NP
1231 type = packed_delta_info(p, &w_curs, curpos,
1232 type, obj_offset, sizep);
2b87c45b 1233 break;
a733cb60 1234 case OBJ_COMMIT:
a733cb60 1235 case OBJ_TREE:
a733cb60 1236 case OBJ_BLOB:
a733cb60 1237 case OBJ_TAG:
2b87c45b
NP
1238 if (sizep)
1239 *sizep = size;
a69d0943 1240 break;
1f688557 1241 default:
08a19d87 1242 die("pack %s contains unknown object type %d",
21666f1a 1243 p->pack_name, type);
1f688557 1244 }
2b87c45b 1245 unuse_pack(&w_curs);
21666f1a 1246 return type;
1f688557
JH
1247}
1248
eb950c19 1249static void *unpack_compressed_entry(struct packed_git *p,
03e79c88 1250 struct pack_window **w_curs,
2b87c45b 1251 unsigned long curpos,
eb950c19 1252 unsigned long size)
de530aaa
SP
1253{
1254 int st;
1255 z_stream stream;
079afb18 1256 unsigned char *buffer, *in;
de530aaa
SP
1257
1258 buffer = xmalloc(size + 1);
1259 buffer[size] = 0;
1260 memset(&stream, 0, sizeof(stream));
de530aaa
SP
1261 stream.next_out = buffer;
1262 stream.avail_out = size;
1263
1264 inflateInit(&stream);
079afb18 1265 do {
2b87c45b 1266 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18
SP
1267 stream.next_in = in;
1268 st = inflate(&stream, Z_FINISH);
2b87c45b 1269 curpos += stream.next_in - in;
079afb18 1270 } while (st == Z_OK || st == Z_BUF_ERROR);
de530aaa
SP
1271 inflateEnd(&stream);
1272 if ((st != Z_STREAM_END) || stream.total_out != size) {
1273 free(buffer);
1274 return NULL;
1275 }
1276
1277 return buffer;
1278}
1279
eb950c19 1280static void *unpack_delta_entry(struct packed_git *p,
03e79c88 1281 struct pack_window **w_curs,
2b87c45b 1282 unsigned long curpos,
1f688557 1283 unsigned long delta_size,
eb32d236 1284 unsigned long obj_offset,
21666f1a 1285 enum object_type *type,
eb950c19 1286 unsigned long *sizep)
1f688557 1287{
7c3e8be3 1288 void *delta_data, *result, *base;
21666f1a 1289 unsigned long base_size, base_offset;
43057304 1290
21666f1a 1291 base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
4d703a1a 1292 base = unpack_entry(p, base_offset, type, &base_size);
67686d95 1293 if (!base)
43057304
NP
1294 die("failed to read delta base object at %lu from %s",
1295 base_offset, p->pack_name);
67686d95 1296
2b87c45b 1297 delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size);
1f688557
JH
1298 result = patch_delta(base, base_size,
1299 delta_data, delta_size,
21666f1a 1300 sizep);
1f688557
JH
1301 if (!result)
1302 die("failed to apply delta");
1303 free(delta_data);
1304 free(base);
1f688557
JH
1305 return result;
1306}
1307
2b87c45b 1308void *unpack_entry(struct packed_git *p, unsigned long obj_offset,
21666f1a 1309 enum object_type *type, unsigned long *sizep)
1f688557 1310{
03e79c88 1311 struct pack_window *w_curs = NULL;
21666f1a
NP
1312 unsigned long curpos = obj_offset;
1313 void *data;
1f688557 1314
21666f1a
NP
1315 *type = unpack_object_header(p, &w_curs, &curpos, sizep);
1316 switch (*type) {
eb32d236
NP
1317 case OBJ_OFS_DELTA:
1318 case OBJ_REF_DELTA:
21666f1a
NP
1319 data = unpack_delta_entry(p, &w_curs, curpos, *sizep,
1320 obj_offset, type, sizep);
4d703a1a 1321 break;
a733cb60 1322 case OBJ_COMMIT:
a733cb60 1323 case OBJ_TREE:
a733cb60 1324 case OBJ_BLOB:
a733cb60 1325 case OBJ_TAG:
21666f1a 1326 data = unpack_compressed_entry(p, &w_curs, curpos, *sizep);
4d703a1a 1327 break;
1f688557 1328 default:
21666f1a 1329 die("unknown object type %i in %s", *type, p->pack_name);
1f688557 1330 }
03e79c88 1331 unuse_pack(&w_curs);
21666f1a 1332 return data;
1f688557
JH
1333}
1334
9a217f2a
JH
1335int num_packed_objects(const struct packed_git *p)
1336{
f9253394 1337 /* See check_packed_git_idx() */
9a217f2a
JH
1338 return (p->index_size - 20 - 20 - 4*256) / 24;
1339}
1340
1341int nth_packed_object_sha1(const struct packed_git *p, int n,
1342 unsigned char* sha1)
1343{
1344 void *index = p->index_base + 256;
1345 if (n < 0 || num_packed_objects(p) <= n)
1346 return -1;
e702496e 1347 hashcpy(sha1, (unsigned char *) index + (24 * n) + 4);
9a217f2a
JH
1348 return 0;
1349}
1350
43057304
NP
1351unsigned long find_pack_entry_one(const unsigned char *sha1,
1352 struct packed_git *p)
1f688557 1353{
b18b00a6 1354 uint32_t *level1_ofs = p->index_base;
1f688557
JH
1355 int hi = ntohl(level1_ofs[*sha1]);
1356 int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
1357 void *index = p->index_base + 256;
1358
1359 do {
1360 int mi = (lo + hi) / 2;
a89fccd2 1361 int cmp = hashcmp((unsigned char *)index + (24 * mi) + 4, sha1);
43057304 1362 if (!cmp)
b18b00a6 1363 return ntohl(*((uint32_t *)((char *)index + (24 * mi))));
1f688557
JH
1364 if (cmp > 0)
1365 hi = mi;
1366 else
1367 lo = mi+1;
1368 } while (lo < hi);
1369 return 0;
1370}
1371
d4ff6d92
SP
1372static int matches_pack_name(struct packed_git *p, const char *ig)
1373{
1374 const char *last_c, *c;
1375
1376 if (!strcmp(p->pack_name, ig))
1377 return 0;
1378
1379 for (c = p->pack_name, last_c = c; *c;)
1380 if (*c == '/')
1381 last_c = ++c;
1382 else
1383 ++c;
1384 if (!strcmp(last_c, ig))
1385 return 0;
1386
1387 return 1;
1388}
1389
106d710b 1390static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e, const char **ignore_packed)
1f688557
JH
1391{
1392 struct packed_git *p;
43057304
NP
1393 unsigned long offset;
1394
1f688557
JH
1395 prepare_packed_git();
1396
1397 for (p = packed_git; p; p = p->next) {
106d710b
JH
1398 if (ignore_packed) {
1399 const char **ig;
1400 for (ig = ignore_packed; *ig; ig++)
d4ff6d92 1401 if (!matches_pack_name(p, *ig))
106d710b
JH
1402 break;
1403 if (*ig)
1404 continue;
1405 }
43057304
NP
1406 offset = find_pack_entry_one(sha1, p);
1407 if (offset) {
c715f783
SP
1408 /*
1409 * We are about to tell the caller where they can
1410 * locate the requested object. We better make
1411 * sure the packfile is still here and can be
1412 * accessed before supplying that answer, as
1413 * it may have been deleted since the index
1414 * was loaded!
1415 */
1416 if (p->pack_fd == -1 && open_packed_git(p)) {
1417 error("packfile %s cannot be accessed", p->pack_name);
1418 continue;
1419 }
43057304
NP
1420 e->offset = offset;
1421 e->p = p;
1422 hashcpy(e->sha1, sha1);
1f688557 1423 return 1;
43057304 1424 }
1f688557
JH
1425 }
1426 return 0;
1427}
1428
bf592c50
DB
1429struct packed_git *find_sha1_pack(const unsigned char *sha1,
1430 struct packed_git *packs)
1431{
1432 struct packed_git *p;
bf592c50
DB
1433
1434 for (p = packs; p; p = p->next) {
43057304 1435 if (find_pack_entry_one(sha1, p))
bf592c50
DB
1436 return p;
1437 }
1438 return NULL;
21666f1a 1439
bf592c50
DB
1440}
1441
21666f1a 1442static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep)
65c2e0c3 1443{
36e4d74a 1444 int status;
65c2e0c3
JH
1445 unsigned long mapsize, size;
1446 void *map;
1447 z_stream stream;
d65a16f6 1448 char hdr[32];
65c2e0c3 1449
bb6b8e4f 1450 map = map_sha1_file(sha1, &mapsize);
f0df4ed5
JS
1451 if (!map)
1452 return error("unable to find %s", sha1_to_hex(sha1));
36e4d74a
JH
1453 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1454 status = error("unable to unpack %s header",
1455 sha1_to_hex(sha1));
21666f1a 1456 else if ((status = parse_sha1_header(hdr, &size)) < 0)
36e4d74a 1457 status = error("unable to parse %s header", sha1_to_hex(sha1));
21666f1a
NP
1458 else if (sizep)
1459 *sizep = size;
65c2e0c3
JH
1460 inflateEnd(&stream);
1461 munmap(map, mapsize);
1462 return status;
1463}
1464
21666f1a 1465int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
f0df4ed5 1466{
f0df4ed5
JS
1467 struct pack_entry e;
1468
1469 if (!find_pack_entry(sha1, &e, NULL)) {
1470 reprepare_packed_git();
1471 if (!find_pack_entry(sha1, &e, NULL))
21666f1a 1472 return sha1_loose_object_info(sha1, sizep);
f0df4ed5 1473 }
21666f1a 1474 return packed_object_info(e.p, e.offset, sizep);
f0df4ed5
JS
1475}
1476
21666f1a
NP
1477static void *read_packed_sha1(const unsigned char *sha1,
1478 enum object_type *type, unsigned long *size)
1f688557
JH
1479{
1480 struct pack_entry e;
1481
8276c007 1482 if (!find_pack_entry(sha1, &e, NULL))
1f688557 1483 return NULL;
8276c007
PE
1484 else
1485 return unpack_entry(e.p, e.offset, type, size);
1f688557
JH
1486}
1487
d66b37bb
JH
1488/*
1489 * This is meant to hold a *small* number of objects that you would
1490 * want read_sha1_file() to be able to return, but yet you do not want
1491 * to write them into the object store (e.g. a browse-only
1492 * application).
1493 */
1494static struct cached_object {
1495 unsigned char sha1[20];
21666f1a 1496 enum object_type type;
d66b37bb
JH
1497 void *buf;
1498 unsigned long size;
1499} *cached_objects;
1500static int cached_object_nr, cached_object_alloc;
1501
1502static struct cached_object *find_cached_object(const unsigned char *sha1)
1503{
1504 int i;
1505 struct cached_object *co = cached_objects;
1506
1507 for (i = 0; i < cached_object_nr; i++, co++) {
1508 if (!hashcmp(co->sha1, sha1))
1509 return co;
1510 }
1511 return NULL;
1512}
1513
21666f1a
NP
1514int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
1515 unsigned char *sha1)
d66b37bb
JH
1516{
1517 struct cached_object *co;
1518
21666f1a 1519 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
1520 if (has_sha1_file(sha1) || find_cached_object(sha1))
1521 return 0;
1522 if (cached_object_alloc <= cached_object_nr) {
1523 cached_object_alloc = alloc_nr(cached_object_alloc);
1524 cached_objects = xrealloc(cached_objects,
1525 sizeof(*cached_objects) *
1526 cached_object_alloc);
1527 }
1528 co = &cached_objects[cached_object_nr++];
1529 co->size = len;
21666f1a 1530 co->type = type;
efa13f7b
JH
1531 co->buf = xmalloc(len);
1532 memcpy(co->buf, buf, len);
d66b37bb
JH
1533 hashcpy(co->sha1, sha1);
1534 return 0;
1535}
1536
21666f1a
NP
1537void *read_sha1_file(const unsigned char *sha1, enum object_type *type,
1538 unsigned long *size)
0fcfd160
LT
1539{
1540 unsigned long mapsize;
1541 void *map, *buf;
d66b37bb
JH
1542 struct cached_object *co;
1543
1544 co = find_cached_object(sha1);
1545 if (co) {
1546 buf = xmalloc(co->size + 1);
1547 memcpy(buf, co->buf, co->size);
1548 ((char*)buf)[co->size] = 0;
21666f1a 1549 *type = co->type;
d66b37bb
JH
1550 *size = co->size;
1551 return buf;
1552 }
0fcfd160 1553
8276c007
PE
1554 buf = read_packed_sha1(sha1, type, size);
1555 if (buf)
1556 return buf;
bb6b8e4f 1557 map = map_sha1_file(sha1, &mapsize);
0fcfd160
LT
1558 if (map) {
1559 buf = unpack_sha1_file(map, mapsize, type, size);
1560 munmap(map, mapsize);
1561 return buf;
1562 }
637cdd9d 1563 reprepare_packed_git();
8276c007 1564 return read_packed_sha1(sha1, type, size);
0fcfd160
LT
1565}
1566
40469ee9 1567void *read_object_with_reference(const unsigned char *sha1,
21666f1a 1568 const char *required_type_name,
40469ee9
JH
1569 unsigned long *size,
1570 unsigned char *actual_sha1_return)
f4913f91 1571{
21666f1a 1572 enum object_type type, required_type;
f4913f91
JH
1573 void *buffer;
1574 unsigned long isize;
40469ee9 1575 unsigned char actual_sha1[20];
f4913f91 1576
21666f1a 1577 required_type = type_from_string(required_type_name);
e702496e 1578 hashcpy(actual_sha1, sha1);
40469ee9
JH
1579 while (1) {
1580 int ref_length = -1;
1581 const char *ref_type = NULL;
f4913f91 1582
21666f1a 1583 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
1584 if (!buffer)
1585 return NULL;
21666f1a 1586 if (type == required_type) {
40469ee9
JH
1587 *size = isize;
1588 if (actual_sha1_return)
e702496e 1589 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
1590 return buffer;
1591 }
1592 /* Handle references */
21666f1a 1593 else if (type == OBJ_COMMIT)
40469ee9 1594 ref_type = "tree ";
21666f1a 1595 else if (type == OBJ_TAG)
40469ee9
JH
1596 ref_type = "object ";
1597 else {
1598 free(buffer);
1599 return NULL;
1600 }
1601 ref_length = strlen(ref_type);
f4913f91 1602
40469ee9 1603 if (memcmp(buffer, ref_type, ref_length) ||
1d7f171c 1604 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
1605 free(buffer);
1606 return NULL;
1607 }
1cf58e72 1608 free(buffer);
40469ee9
JH
1609 /* Now we have the ID of the referred-to object in
1610 * actual_sha1. Check again. */
f4913f91 1611 }
f4913f91
JH
1612}
1613
972a9155
RS
1614static void write_sha1_file_prepare(void *buf, unsigned long len,
1615 const char *type, unsigned char *sha1,
d65a16f6 1616 char *hdr, int *hdrlen)
d410c0f5
JH
1617{
1618 SHA_CTX c;
1619
1620 /* Generate the header */
d65a16f6 1621 *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
d410c0f5
JH
1622
1623 /* Sha1.. */
1624 SHA1_Init(&c);
1625 SHA1_Update(&c, hdr, *hdrlen);
1626 SHA1_Update(&c, buf, len);
1627 SHA1_Final(sha1, &c);
d410c0f5
JH
1628}
1629
230f1322
LT
1630/*
1631 * Link the tempfile to the final place, possibly creating the
1632 * last directory level as you do so.
1633 *
1634 * Returns the errno on failure, 0 on success.
1635 */
839837b9 1636static int link_temp_to_file(const char *tmpfile, const char *filename)
230f1322
LT
1637{
1638 int ret;
756aaf4a 1639 char *dir;
230f1322
LT
1640
1641 if (!link(tmpfile, filename))
1642 return 0;
1643
1644 /*
756aaf4a 1645 * Try to mkdir the last path component if that failed.
230f1322
LT
1646 *
1647 * Re-try the "link()" regardless of whether the mkdir
1648 * succeeds, since a race might mean that somebody
1649 * else succeeded.
1650 */
1651 ret = errno;
756aaf4a
SP
1652 dir = strrchr(filename, '/');
1653 if (dir) {
1654 *dir = 0;
866cae0d 1655 if (!mkdir(filename, 0777) && adjust_shared_perm(filename)) {
91c23e48 1656 *dir = '/';
756aaf4a 1657 return -2;
91c23e48 1658 }
756aaf4a
SP
1659 *dir = '/';
1660 if (!link(tmpfile, filename))
1661 return 0;
1662 ret = errno;
230f1322
LT
1663 }
1664 return ret;
1665}
1666
1667/*
1668 * Move the just written object into its final resting place
1669 */
839837b9 1670int move_temp_to_file(const char *tmpfile, const char *filename)
230f1322
LT
1671{
1672 int ret = link_temp_to_file(tmpfile, filename);
7ebb6fca
LT
1673
1674 /*
1675 * Coda hack - coda doesn't like cross-directory links,
1676 * so we fall back to a rename, which will mean that it
1677 * won't be able to check collisions, but that's not a
1678 * big deal.
1679 *
1680 * The same holds for FAT formatted media.
1681 *
1682 * When this succeeds, we just return 0. We have nothing
1683 * left to unlink.
1684 */
1685 if (ret && ret != EEXIST) {
1686 if (!rename(tmpfile, filename))
230f1322 1687 return 0;
9e48b389 1688 ret = errno;
230f1322
LT
1689 }
1690 unlink(tmpfile);
1691 if (ret) {
1692 if (ret != EEXIST) {
916d081b 1693 return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret));
230f1322
LT
1694 }
1695 /* FIXME!!! Collision check here ? */
1696 }
1697
1698 return 0;
1699}
1700
4d548150
LT
1701static int write_buffer(int fd, const void *buf, size_t len)
1702{
d34cf19b 1703 if (write_in_full(fd, buf, len) < 0)
93822c22 1704 return error("file write error (%s)", strerror(errno));
4d548150
LT
1705 return 0;
1706}
1707
93821bd9
LT
1708static int write_binary_header(unsigned char *hdr, enum object_type type, unsigned long len)
1709{
1710 int hdr_len;
1711 unsigned char c;
1712
1713 c = (type << 4) | (len & 15);
1714 len >>= 4;
1715 hdr_len = 1;
1716 while (len) {
1717 *hdr++ = c | 0x80;
1718 hdr_len++;
1719 c = (len & 0x7f);
1720 len >>= 7;
1721 }
1722 *hdr = c;
1723 return hdr_len;
1724}
1725
1726static void setup_object_header(z_stream *stream, const char *type, unsigned long len)
1727{
d65a16f6 1728 int obj_type, hdrlen;
93821bd9
LT
1729
1730 if (use_legacy_headers) {
1731 while (deflate(stream, 0) == Z_OK)
1732 /* nothing */;
1733 return;
1734 }
df843662 1735 obj_type = type_from_string(type);
d65a16f6
NP
1736 hdrlen = write_binary_header(stream->next_out, obj_type, len);
1737 stream->total_out = hdrlen;
1738 stream->next_out += hdrlen;
1739 stream->avail_out -= hdrlen;
93821bd9
LT
1740}
1741
abdc3fc8
RS
1742int hash_sha1_file(void *buf, unsigned long len, const char *type,
1743 unsigned char *sha1)
1744{
d65a16f6 1745 char hdr[32];
abdc3fc8
RS
1746 int hdrlen;
1747 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1748 return 0;
1749}
1750
bf0f910d 1751int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
0fcfd160
LT
1752{
1753 int size;
bf0f910d 1754 unsigned char *compressed;
0fcfd160
LT
1755 z_stream stream;
1756 unsigned char sha1[20];
706bc531 1757 char *filename;
aac17941 1758 static char tmpfile[PATH_MAX];
d65a16f6 1759 char hdr[32];
230f1322 1760 int fd, hdrlen;
a44c9a5e 1761
d410c0f5
JH
1762 /* Normally if we have it in the pack then we do not bother writing
1763 * it out into .git/objects/??/?{38} file.
1764 */
972a9155
RS
1765 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1766 filename = sha1_file_name(sha1);
706bc531 1767 if (returnsha1)
e702496e 1768 hashcpy(returnsha1, sha1);
d410c0f5
JH
1769 if (has_sha1_file(sha1))
1770 return 0;
aac17941
LT
1771 fd = open(filename, O_RDONLY);
1772 if (fd >= 0) {
706bc531 1773 /*
aac17941
LT
1774 * FIXME!!! We might do collision checking here, but we'd
1775 * need to uncompress the old file and check it. Later.
706bc531 1776 */
aac17941 1777 close(fd);
706bc531
LT
1778 return 0;
1779 }
1780
aac17941 1781 if (errno != ENOENT) {
916d081b 1782 return error("sha1 file %s: %s\n", filename, strerror(errno));
aac17941
LT
1783 }
1784
1785 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
ace1534d 1786
aac17941
LT
1787 fd = mkstemp(tmpfile);
1788 if (fd < 0) {
916d081b
PB
1789 if (errno == EPERM)
1790 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
1791 else
1792 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
aac17941
LT
1793 }
1794
0fcfd160
LT
1795 /* Set it up */
1796 memset(&stream, 0, sizeof(stream));
12f6c308 1797 deflateInit(&stream, zlib_compression_level);
93821bd9 1798 size = 8 + deflateBound(&stream, len+hdrlen);
812666c8 1799 compressed = xmalloc(size);
0fcfd160
LT
1800
1801 /* Compress it */
0fcfd160
LT
1802 stream.next_out = compressed;
1803 stream.avail_out = size;
a44c9a5e
LT
1804
1805 /* First header.. */
d65a16f6 1806 stream.next_in = (unsigned char *)hdr;
a44c9a5e 1807 stream.avail_in = hdrlen;
93821bd9 1808 setup_object_header(&stream, type, len);
a44c9a5e
LT
1809
1810 /* Then the data itself.. */
1811 stream.next_in = buf;
1812 stream.avail_in = len;
0fcfd160
LT
1813 while (deflate(&stream, Z_FINISH) == Z_OK)
1814 /* nothing */;
1815 deflateEnd(&stream);
1816 size = stream.total_out;
1817
4d548150
LT
1818 if (write_buffer(fd, compressed, size) < 0)
1819 die("unable to write sha1 file");
aac17941 1820 fchmod(fd, 0444);
706bc531 1821 close(fd);
383f85b7 1822 free(compressed);
0fcfd160 1823
230f1322 1824 return move_temp_to_file(tmpfile, filename);
0fcfd160 1825}
8237b185 1826
4d548150
LT
1827/*
1828 * We need to unpack and recompress the object for writing
1829 * it out to a different file.
1830 */
1831static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
a5eda52b 1832{
4d548150 1833 size_t size;
a5eda52b 1834 z_stream stream;
4d548150
LT
1835 unsigned char *unpacked;
1836 unsigned long len;
21666f1a 1837 enum object_type type;
d65a16f6 1838 char hdr[32];
4d548150
LT
1839 int hdrlen;
1840 void *buf;
bfc66daf 1841
a9486b02 1842 /* need to unpack and recompress it by itself */
21666f1a 1843 unpacked = read_packed_sha1(sha1, &type, &len);
8276c007
PE
1844 if (!unpacked)
1845 error("cannot read sha1_file for %s", sha1_to_hex(sha1));
a5eda52b 1846
21666f1a 1847 hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
a5eda52b 1848
4d548150
LT
1849 /* Set it up */
1850 memset(&stream, 0, sizeof(stream));
12f6c308 1851 deflateInit(&stream, zlib_compression_level);
4d548150
LT
1852 size = deflateBound(&stream, len + hdrlen);
1853 buf = xmalloc(size);
a5eda52b 1854
4d548150
LT
1855 /* Compress it */
1856 stream.next_out = buf;
1857 stream.avail_out = size;
a5eda52b 1858
4d548150
LT
1859 /* First header.. */
1860 stream.next_in = (void *)hdr;
1861 stream.avail_in = hdrlen;
1862 while (deflate(&stream, 0) == Z_OK)
1863 /* nothing */;
bfc66daf 1864
4d548150
LT
1865 /* Then the data itself.. */
1866 stream.next_in = unpacked;
1867 stream.avail_in = len;
1868 while (deflate(&stream, Z_FINISH) == Z_OK)
1869 /* nothing */;
1870 deflateEnd(&stream);
1871 free(unpacked);
bfc66daf 1872
4d548150
LT
1873 *objsize = stream.total_out;
1874 return buf;
1875}
1876
1877int write_sha1_to_fd(int fd, const unsigned char *sha1)
1878{
1879 int retval;
1880 unsigned long objsize;
bb6b8e4f 1881 void *buf = map_sha1_file(sha1, &objsize);
4d548150
LT
1882
1883 if (buf) {
1884 retval = write_buffer(fd, buf, objsize);
1885 munmap(buf, objsize);
1886 return retval;
1887 }
1888
1889 buf = repack_object(sha1, &objsize);
1890 retval = write_buffer(fd, buf, objsize);
1891 free(buf);
1892 return retval;
a5eda52b
DB
1893}
1894
70b9829e
DB
1895int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
1896 size_t bufsize, size_t *bufposn)
8237b185 1897{
230f1322 1898 char tmpfile[PATH_MAX];
8237b185
DB
1899 int local;
1900 z_stream stream;
1901 unsigned char real_sha1[20];
bf0f910d 1902 unsigned char discard[4096];
8237b185
DB
1903 int ret;
1904 SHA_CTX c;
1905
230f1322 1906 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
8237b185 1907
230f1322 1908 local = mkstemp(tmpfile);
916d081b
PB
1909 if (local < 0) {
1910 if (errno == EPERM)
1911 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
1912 else
1913 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
1914 }
8237b185
DB
1915
1916 memset(&stream, 0, sizeof(stream));
1917
1918 inflateInit(&stream);
1919
1920 SHA1_Init(&c);
1921
1922 do {
1923 ssize_t size;
70b9829e
DB
1924 if (*bufposn) {
1925 stream.avail_in = *bufposn;
96ad15ae 1926 stream.next_in = (unsigned char *) buffer;
70b9829e
DB
1927 do {
1928 stream.next_out = discard;
1929 stream.avail_out = sizeof(discard);
1930 ret = inflate(&stream, Z_SYNC_FLUSH);
1931 SHA1_Update(&c, discard, sizeof(discard) -
1932 stream.avail_out);
1933 } while (stream.avail_in && ret == Z_OK);
4d548150
LT
1934 if (write_buffer(local, buffer, *bufposn - stream.avail_in) < 0)
1935 die("unable to write sha1 file");
70b9829e
DB
1936 memmove(buffer, buffer + *bufposn - stream.avail_in,
1937 stream.avail_in);
1938 *bufposn = stream.avail_in;
1939 if (ret != Z_OK)
1940 break;
1941 }
93d26e4c 1942 size = xread(fd, buffer + *bufposn, bufsize - *bufposn);
8237b185
DB
1943 if (size <= 0) {
1944 close(local);
230f1322 1945 unlink(tmpfile);
8237b185
DB
1946 if (!size)
1947 return error("Connection closed?");
1948 perror("Reading from connection");
1949 return -1;
1950 }
70b9829e
DB
1951 *bufposn += size;
1952 } while (1);
8237b185
DB
1953 inflateEnd(&stream);
1954
1955 close(local);
1956 SHA1_Final(real_sha1, &c);
1957 if (ret != Z_STREAM_END) {
230f1322 1958 unlink(tmpfile);
8237b185
DB
1959 return error("File %s corrupted", sha1_to_hex(sha1));
1960 }
a89fccd2 1961 if (hashcmp(sha1, real_sha1)) {
230f1322 1962 unlink(tmpfile);
bd2afde8 1963 return error("File %s has bad hash", sha1_to_hex(sha1));
8237b185 1964 }
230f1322
LT
1965
1966 return move_temp_to_file(tmpfile, sha1_file_name(sha1));
8237b185
DB
1967}
1968
bf592c50
DB
1969int has_pack_index(const unsigned char *sha1)
1970{
1971 struct stat st;
1972 if (stat(sha1_pack_index_name(sha1), &st))
1973 return 0;
1974 return 1;
1975}
1976
1977int has_pack_file(const unsigned char *sha1)
1978{
1979 struct stat st;
1980 if (stat(sha1_pack_name(sha1), &st))
1981 return 0;
1982 return 1;
1983}
1984
106d710b 1985int has_sha1_pack(const unsigned char *sha1, const char **ignore_packed)
dade09c2
LT
1986{
1987 struct pack_entry e;
106d710b 1988 return find_pack_entry(sha1, &e, ignore_packed);
dade09c2
LT
1989}
1990
8237b185
DB
1991int has_sha1_file(const unsigned char *sha1)
1992{
8237b185 1993 struct stat st;
1f688557
JH
1994 struct pack_entry e;
1995
106d710b 1996 if (find_pack_entry(sha1, &e, NULL))
1f688557 1997 return 1;
ab90ea5d 1998 return find_sha1_file(sha1, &st) ? 1 : 0;
8237b185 1999}
74400e71 2000
e7332f96
BE
2001/*
2002 * reads from fd as long as possible into a supplied buffer of size bytes.
82e5a82f 2003 * If necessary the buffer's size is increased using realloc()
e7332f96
BE
2004 *
2005 * returns 0 if anything went fine and -1 otherwise
2006 *
2007 * NOTE: both buf and size may change, but even when -1 is returned
2008 * you still have to free() it yourself.
2009 */
2010int read_pipe(int fd, char** return_buf, unsigned long* return_size)
024510c8 2011{
e7332f96
BE
2012 char* buf = *return_buf;
2013 unsigned long size = *return_size;
2014 int iret;
024510c8 2015 unsigned long off = 0;
e7332f96 2016
024510c8 2017 do {
e7332f96 2018 iret = xread(fd, buf + off, size - off);
024510c8
DB
2019 if (iret > 0) {
2020 off += iret;
2021 if (off == size) {
2022 size *= 2;
83572c1a 2023 buf = xrealloc(buf, size);
024510c8
DB
2024 }
2025 }
2026 } while (iret > 0);
e7332f96
BE
2027
2028 *return_buf = buf;
2029 *return_size = off;
2030
2031 if (iret < 0)
2032 return -1;
2033 return 0;
2034}
2035
2036int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
2037{
2038 unsigned long size = 4096;
2d7320d0 2039 char *buf = xmalloc(size);
e7332f96 2040 int ret;
e7332f96
BE
2041
2042 if (read_pipe(fd, &buf, &size)) {
024510c8
DB
2043 free(buf);
2044 return -1;
2045 }
e7332f96 2046
024510c8 2047 if (!type)
8e440259 2048 type = blob_type;
024510c8 2049 if (write_object)
e7332f96 2050 ret = write_sha1_file(buf, size, type, sha1);
abdc3fc8
RS
2051 else
2052 ret = hash_sha1_file(buf, size, type, sha1);
024510c8
DB
2053 free(buf);
2054 return ret;
2055}
2056
edaec3fb 2057int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object,
53bca91a 2058 enum object_type type, const char *path)
74400e71 2059{
74400e71 2060 unsigned long size = st->st_size;
aac17941 2061 void *buf;
6c510bee 2062 int ret, re_allocated = 0;
74400e71 2063
aac17941 2064 buf = "";
74400e71 2065 if (size)
c4712e45 2066 buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
74400e71 2067 close(fd);
74400e71 2068
7672db20 2069 if (!type)
edaec3fb 2070 type = OBJ_BLOB;
6c510bee
LT
2071
2072 /*
2073 * Convert blobs to git internal format
2074 */
d0d8e14d 2075 if ((type == OBJ_BLOB) && S_ISREG(st->st_mode)) {
6c510bee
LT
2076 unsigned long nsize = size;
2077 char *nbuf = buf;
53bca91a 2078 if (convert_to_git(path, &nbuf, &nsize)) {
6c510bee
LT
2079 if (size)
2080 munmap(buf, size);
2081 size = nsize;
2082 buf = nbuf;
2083 re_allocated = 1;
2084 }
2085 }
2086
7672db20 2087 if (write_object)
edaec3fb 2088 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 2089 else
edaec3fb 2090 ret = hash_sha1_file(buf, size, typename(type), sha1);
6c510bee
LT
2091 if (re_allocated) {
2092 free(buf);
2093 return ret;
2094 }
aac17941
LT
2095 if (size)
2096 munmap(buf, size);
2097 return ret;
74400e71 2098}
ec1fcc16
JH
2099
2100int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
2101{
2102 int fd;
2103 char *target;
2104
2105 switch (st->st_mode & S_IFMT) {
2106 case S_IFREG:
2107 fd = open(path, O_RDONLY);
2108 if (fd < 0)
2109 return error("open(\"%s\"): %s", path,
2110 strerror(errno));
53bca91a 2111 if (index_fd(sha1, fd, st, write_object, OBJ_BLOB, path) < 0)
ec1fcc16
JH
2112 return error("%s: failed to insert into database",
2113 path);
2114 break;
2115 case S_IFLNK:
2116 target = xmalloc(st->st_size+1);
2117 if (readlink(path, target, st->st_size+1) != st->st_size) {
2118 char *errstr = strerror(errno);
2119 free(target);
2120 return error("readlink(\"%s\"): %s", path,
2121 errstr);
2122 }
abdc3fc8
RS
2123 if (!write_object)
2124 hash_sha1_file(target, st->st_size, blob_type, sha1);
2125 else if (write_sha1_file(target, st->st_size, blob_type, sha1))
ec1fcc16
JH
2126 return error("%s: failed to insert into database",
2127 path);
2128 free(target);
2129 break;
2130 default:
2131 return error("%s: unsupported file type", path);
2132 }
2133 return 0;
2134}
a69e5429
JH
2135
2136int read_pack_header(int fd, struct pack_header *header)
2137{
2138 char *c = (char*)header;
2139 ssize_t remaining = sizeof(struct pack_header);
2140 do {
2141 ssize_t r = xread(fd, c, remaining);
2142 if (r <= 0)
2143 /* "eof before pack header was fully read" */
2144 return PH_ERROR_EOF;
2145 remaining -= r;
2146 c += r;
2147 } while (remaining > 0);
2148 if (header->hdr_signature != htonl(PACK_SIGNATURE))
2149 /* "protocol error (pack signature mismatch detected)" */
2150 return PH_ERROR_PACK_SIGNATURE;
2151 if (!pack_version_ok(header->hdr_version))
2152 /* "protocol error (pack version unsupported)" */
2153 return PH_ERROR_PROTOCOL;
2154 return 0;
2155}