Use off_t when we really mean a file offset.
[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
2d88451b
SP
433static int check_packed_git_idx(const char *path,
434 unsigned long *idx_size_,
435 void **idx_map_)
1f688557
JH
436{
437 void *idx_map;
b18b00a6 438 uint32_t *index;
1f688557 439 unsigned long idx_size;
326bf396 440 uint32_t nr, i;
e93ec6f9 441 int fd = open(path, O_RDONLY);
1f688557
JH
442 struct stat st;
443 if (fd < 0)
444 return -1;
445 if (fstat(fd, &st)) {
446 close(fd);
447 return -1;
448 }
449 idx_size = st.st_size;
2d88451b
SP
450 if (idx_size < 4 * 256 + 20 + 20) {
451 close(fd);
452 return error("index file %s is too small", path);
453 }
c4712e45 454 idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
1f688557 455 close(fd);
1f688557
JH
456
457 index = idx_map;
4d235c80
LT
458 *idx_map_ = idx_map;
459 *idx_size_ = idx_size;
1f688557 460
df1b059d
SP
461 /* a future index format would start with this, as older git
462 * binaries would fail the non-monotonic index check below.
463 * give a nicer warning to the user if we can.
464 */
2d88451b
SP
465 if (index[0] == htonl(PACK_IDX_SIGNATURE)) {
466 munmap(idx_map, idx_size);
df1b059d
SP
467 return error("index file %s is a newer version"
468 " and is not supported by this binary"
469 " (try upgrading GIT to a newer version)",
470 path);
2d88451b 471 }
df1b059d 472
1f688557
JH
473 nr = 0;
474 for (i = 0; i < 256; i++) {
326bf396 475 uint32_t n = ntohl(index[i]);
2d88451b
SP
476 if (n < nr) {
477 munmap(idx_map, idx_size);
df1b059d 478 return error("non-monotonic index %s", path);
2d88451b 479 }
1f688557
JH
480 nr = n;
481 }
482
483 /*
484 * Total size:
485 * - 256 index entries 4 bytes each
486 * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
487 * - 20-byte SHA1 of the packfile
488 * - 20-byte SHA1 file checksum
489 */
2d88451b
SP
490 if (idx_size != 4*256 + nr * 24 + 20 + 20) {
491 munmap(idx_map, idx_size);
df1b059d 492 return error("wrong index file size in %s", path);
2d88451b 493 }
1f688557 494
1f688557
JH
495 return 0;
496}
497
11daf39b
SP
498static void scan_windows(struct packed_git *p,
499 struct packed_git **lru_p,
500 struct pack_window **lru_w,
501 struct pack_window **lru_l)
1f688557 502{
11daf39b
SP
503 struct pack_window *w, *w_l;
504
505 for (w_l = NULL, w = p->windows; w; w = w->next) {
506 if (!w->inuse_cnt) {
507 if (!*lru_w || w->last_used < (*lru_w)->last_used) {
508 *lru_p = p;
509 *lru_w = w;
510 *lru_l = w_l;
54044bf8 511 }
54044bf8 512 }
11daf39b 513 w_l = w;
f9253394 514 }
11daf39b
SP
515}
516
517static int unuse_one_window(struct packed_git *current)
518{
519 struct packed_git *p, *lru_p = NULL;
520 struct pack_window *lru_w = NULL, *lru_l = NULL;
521
522 if (current)
523 scan_windows(current, &lru_p, &lru_w, &lru_l);
524 for (p = packed_git; p; p = p->next)
525 scan_windows(p, &lru_p, &lru_w, &lru_l);
54044bf8
SP
526 if (lru_p) {
527 munmap(lru_w->base, lru_w->len);
528 pack_mapped -= lru_w->len;
529 if (lru_l)
530 lru_l->next = lru_w->next;
531 else {
532 lru_p->windows = lru_w->next;
11daf39b 533 if (!lru_p->windows && lru_p != current) {
54044bf8
SP
534 close(lru_p->pack_fd);
535 lru_p->pack_fd = -1;
536 }
537 }
538 free(lru_w);
a53128b6 539 pack_open_windows--;
54044bf8
SP
540 return 1;
541 }
542 return 0;
f9253394
JH
543}
544
97bfeb34
SP
545void release_pack_memory(size_t need)
546{
547 size_t cur = pack_mapped;
548 while (need >= (cur - pack_mapped) && unuse_one_window(NULL))
549 ; /* nothing */
550}
551
03e79c88 552void unuse_pack(struct pack_window **w_cursor)
f9253394 553{
03e79c88
SP
554 struct pack_window *w = *w_cursor;
555 if (w) {
556 w->inuse_cnt--;
557 *w_cursor = NULL;
558 }
1f688557
JH
559}
560
3cf8b462
SP
561/*
562 * Do not call this directly as this leaks p->pack_fd on error return;
563 * call open_packed_git() instead.
564 */
565static int open_packed_git_1(struct packed_git *p)
1f688557 566{
9bc879c1
SP
567 struct stat st;
568 struct pack_header hdr;
569 unsigned char sha1[20];
570 unsigned char *idx_sha1;
2c039da8 571 long fd_flag;
9bc879c1
SP
572
573 p->pack_fd = open(p->pack_name, O_RDONLY);
574 if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
072db278 575 return -1;
9bc879c1
SP
576
577 /* If we created the struct before we had the pack we lack size. */
bf592c50 578 if (!p->pack_size) {
bf592c50 579 if (!S_ISREG(st.st_mode))
072db278 580 return error("packfile %s not a regular file", p->pack_name);
bf592c50 581 p->pack_size = st.st_size;
9bc879c1 582 } else if (p->pack_size != st.st_size)
072db278 583 return error("packfile %s size changed", p->pack_name);
9bc879c1 584
2c039da8
JH
585 /* We leave these file descriptors open with sliding mmap;
586 * there is no point keeping them open across exec(), though.
587 */
588 fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
589 if (fd_flag < 0)
072db278 590 return error("cannot determine file descriptor flags");
2c039da8
JH
591 fd_flag |= FD_CLOEXEC;
592 if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
072db278 593 return error("cannot set FD_CLOEXEC");
2c039da8 594
9bc879c1 595 /* Verify we recognize this pack file format. */
e6e2bd62 596 if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
072db278 597 return error("file %s is far too short to be a packfile", p->pack_name);
9bc879c1 598 if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
072db278 599 return error("file %s is not a GIT packfile", p->pack_name);
9bc879c1 600 if (!pack_version_ok(hdr.hdr_version))
072db278 601 return error("packfile %s is version %u and not supported"
9bc879c1
SP
602 " (try upgrading GIT to a newer version)",
603 p->pack_name, ntohl(hdr.hdr_version));
604
605 /* Verify the pack matches its index. */
606 if (num_packed_objects(p) != ntohl(hdr.hdr_entries))
072db278 607 return error("packfile %s claims to have %u objects"
9bc879c1
SP
608 " while index size indicates %u objects",
609 p->pack_name, ntohl(hdr.hdr_entries),
610 num_packed_objects(p));
611 if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
072db278 612 return error("end of packfile %s is unavailable", p->pack_name);
e6e2bd62 613 if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
072db278 614 return error("packfile %s signature is unavailable", p->pack_name);
9bc879c1
SP
615 idx_sha1 = ((unsigned char *)p->index_base) + p->index_size - 40;
616 if (hashcmp(sha1, idx_sha1))
072db278
SP
617 return error("packfile %s does not match index", p->pack_name);
618 return 0;
9bc879c1
SP
619}
620
3cf8b462
SP
621static int open_packed_git(struct packed_git *p)
622{
623 if (!open_packed_git_1(p))
624 return 0;
625 if (p->pack_fd != -1) {
626 close(p->pack_fd);
627 p->pack_fd = -1;
628 }
629 return -1;
630}
631
c4001d92 632static int in_window(struct pack_window *win, off_t offset)
60bb8b14
SP
633{
634 /* We must promise at least 20 bytes (one hash) after the
635 * offset is available from this window, otherwise the offset
636 * is not actually in this window and a different window (which
637 * has that one hash excess) must be used. This is to support
638 * the object header and delta base parsing routines below.
639 */
640 off_t win_off = win->offset;
641 return win_off <= offset
642 && (offset + 20) <= (win_off + win->len);
643}
644
03e79c88
SP
645unsigned char* use_pack(struct packed_git *p,
646 struct pack_window **w_cursor,
c4001d92 647 off_t offset,
03e79c88 648 unsigned int *left)
9bc879c1 649{
60bb8b14 650 struct pack_window *win = *w_cursor;
03e79c88 651
072db278
SP
652 if (p->pack_fd == -1 && open_packed_git(p))
653 die("packfile %s cannot be accessed", p->pack_name);
60bb8b14
SP
654
655 /* Since packfiles end in a hash of their content and its
656 * pointless to ask for an offset into the middle of that
657 * hash, and the in_window function above wouldn't match
658 * don't allow an offset too close to the end of the file.
659 */
660 if (offset > (p->pack_size - 20))
661 die("offset beyond end of packfile (truncated pack?)");
662
663 if (!win || !in_window(win, offset)) {
664 if (win)
665 win->inuse_cnt--;
666 for (win = p->windows; win; win = win->next) {
667 if (in_window(win, offset))
668 break;
669 }
670 if (!win) {
78a28df9 671 size_t window_align = packed_git_window_size / 2;
60bb8b14 672 win = xcalloc(1, sizeof(*win));
78a28df9 673 win->offset = (offset / window_align) * window_align;
60bb8b14
SP
674 win->len = p->pack_size - win->offset;
675 if (win->len > packed_git_window_size)
676 win->len = packed_git_window_size;
677 pack_mapped += win->len;
11daf39b
SP
678 while (packed_git_limit < pack_mapped
679 && unuse_one_window(p))
60bb8b14 680 ; /* nothing */
c4712e45 681 win->base = xmmap(NULL, win->len,
60bb8b14
SP
682 PROT_READ, MAP_PRIVATE,
683 p->pack_fd, win->offset);
684 if (win->base == MAP_FAILED)
73b4e4be
SP
685 die("packfile %s cannot be mapped: %s",
686 p->pack_name,
687 strerror(errno));
a53128b6
SP
688 pack_mmap_calls++;
689 pack_open_windows++;
690 if (pack_mapped > peak_pack_mapped)
691 peak_pack_mapped = pack_mapped;
692 if (pack_open_windows > peak_pack_open_windows)
693 peak_pack_open_windows = pack_open_windows;
60bb8b14
SP
694 win->next = p->windows;
695 p->windows = win;
696 }
1f688557 697 }
03e79c88
SP
698 if (win != *w_cursor) {
699 win->last_used = pack_used_ctr++;
700 win->inuse_cnt++;
701 *w_cursor = win;
702 }
60bb8b14 703 offset -= win->offset;
03e79c88
SP
704 if (left)
705 *left = win->len - offset;
706 return win->base + offset;
1f688557
JH
707}
708
9d835df2 709struct packed_git *add_packed_git(char *path, int path_len, int local)
1f688557
JH
710{
711 struct stat st;
712 struct packed_git *p;
713 unsigned long idx_size;
714 void *idx_map;
c0bbbb1b 715 unsigned char sha1[20];
1f688557
JH
716
717 if (check_packed_git_idx(path, &idx_size, &idx_map))
718 return NULL;
719
720 /* do we have a corresponding .pack file? */
721 strcpy(path + path_len - 4, ".pack");
722 if (stat(path, &st) || !S_ISREG(st.st_mode)) {
723 munmap(idx_map, idx_size);
724 return NULL;
725 }
726 /* ok, it looks sane as far as we can check without
727 * actually mapping the pack file.
728 */
729 p = xmalloc(sizeof(*p) + path_len + 2);
730 strcpy(p->pack_name, path);
731 p->index_size = idx_size;
732 p->pack_size = st.st_size;
733 p->index_base = idx_map;
734 p->next = NULL;
c41ee586 735 p->windows = NULL;
9bc879c1 736 p->pack_fd = -1;
9d835df2 737 p->pack_local = local;
f4a11066 738 if ((path_len > 44) && !get_sha1_hex(path + path_len - 44, sha1))
e702496e 739 hashcpy(p->sha1, sha1);
1f688557
JH
740 return p;
741}
742
bf592c50 743struct packed_git *parse_pack_index(unsigned char *sha1)
c508df5e
DB
744{
745 char *path = sha1_pack_index_name(sha1);
746 return parse_pack_index_file(sha1, path);
747}
748
2ab141a2 749struct packed_git *parse_pack_index_file(const unsigned char *sha1, char *idx_path)
bf592c50
DB
750{
751 struct packed_git *p;
752 unsigned long idx_size;
753 void *idx_map;
c508df5e 754 char *path;
bf592c50 755
c508df5e 756 if (check_packed_git_idx(idx_path, &idx_size, &idx_map))
bf592c50
DB
757 return NULL;
758
759 path = sha1_pack_name(sha1);
760
761 p = xmalloc(sizeof(*p) + strlen(path) + 2);
762 strcpy(p->pack_name, path);
763 p->index_size = idx_size;
764 p->pack_size = 0;
765 p->index_base = idx_map;
766 p->next = NULL;
c41ee586 767 p->windows = NULL;
9bc879c1 768 p->pack_fd = -1;
e702496e 769 hashcpy(p->sha1, sha1);
bf592c50
DB
770 return p;
771}
772
773void install_packed_git(struct packed_git *pack)
774{
775 pack->next = packed_git;
776 packed_git = pack;
777}
778
9d835df2 779static void prepare_packed_git_one(char *objdir, int local)
1f688557
JH
780{
781 char path[PATH_MAX];
782 int len;
783 DIR *dir;
784 struct dirent *de;
785
786 sprintf(path, "%s/pack", objdir);
787 len = strlen(path);
788 dir = opendir(path);
b5b16990 789 if (!dir) {
26125f6b 790 if (errno != ENOENT)
bd2afde8 791 error("unable to open object pack directory: %s: %s",
26125f6b 792 path, strerror(errno));
1f688557 793 return;
b5b16990 794 }
1f688557
JH
795 path[len++] = '/';
796 while ((de = readdir(dir)) != NULL) {
797 int namelen = strlen(de->d_name);
798 struct packed_git *p;
799
5bb1cda5 800 if (!has_extension(de->d_name, ".idx"))
1f688557
JH
801 continue;
802
54a15a8d 803 /* Don't reopen a pack we already have. */
1f688557 804 strcpy(path + len, de->d_name);
86f7780c
JK
805 for (p = packed_git; p; p = p->next) {
806 if (!memcmp(path, p->pack_name, len + namelen - 4))
807 break;
808 }
809 if (p)
810 continue;
54a15a8d
SP
811 /* See if it really is a valid .idx file with corresponding
812 * .pack file that we can map.
813 */
9d835df2 814 p = add_packed_git(path, len + namelen, local);
1f688557
JH
815 if (!p)
816 continue;
625e9421 817 install_packed_git(p);
1f688557 818 }
5b35bcd5 819 closedir(dir);
1f688557
JH
820}
821
637cdd9d 822static int prepare_packed_git_run_once = 0;
9a217f2a 823void prepare_packed_git(void)
1f688557 824{
d5a63b99 825 struct alternate_object_database *alt;
1f688557 826
637cdd9d 827 if (prepare_packed_git_run_once)
1f688557 828 return;
9d835df2 829 prepare_packed_git_one(get_object_directory(), 1);
9a217f2a 830 prepare_alt_odb();
d5a63b99 831 for (alt = alt_odb_list; alt; alt = alt->next) {
1494e038 832 alt->name[-1] = 0;
9d835df2 833 prepare_packed_git_one(alt->base, 0);
1494e038 834 alt->name[-1] = '/';
1f688557 835 }
637cdd9d
JK
836 prepare_packed_git_run_once = 1;
837}
838
fc04c412 839void reprepare_packed_git(void)
637cdd9d
JK
840{
841 prepare_packed_git_run_once = 0;
842 prepare_packed_git();
1f688557
JH
843}
844
5d6ccf5c 845int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
0fcfd160
LT
846{
847 unsigned char real_sha1[20];
7cfb5f36 848 hash_sha1_file(map, size, type, real_sha1);
a89fccd2 849 return hashcmp(sha1, real_sha1) ? -1 : 0;
0fcfd160
LT
850}
851
bb6b8e4f 852void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
0fcfd160 853{
0fcfd160
LT
854 struct stat st;
855 void *map;
144bde78 856 int fd;
ace1534d
JH
857 char *filename = find_sha1_file(sha1, &st);
858
859 if (!filename) {
ace1534d
JH
860 return NULL;
861 }
0fcfd160 862
144bde78 863 fd = open(filename, O_RDONLY | sha1_file_open_flag);
0fcfd160 864 if (fd < 0) {
144bde78
LT
865 /* See if it works without O_NOATIME */
866 switch (sha1_file_open_flag) {
867 default:
868 fd = open(filename, O_RDONLY);
869 if (fd >= 0)
870 break;
871 /* Fallthrough */
872 case 0:
144bde78
LT
873 return NULL;
874 }
875
1f688557
JH
876 /* If it failed once, it will probably fail again.
877 * Stop using O_NOATIME
878 */
144bde78 879 sha1_file_open_flag = 0;
0fcfd160 880 }
c4712e45 881 map = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
0fcfd160 882 close(fd);
0fcfd160
LT
883 *size = st.st_size;
884 return map;
885}
886
bb6b8e4f
JH
887int legacy_loose_object(unsigned char *map)
888{
889 unsigned int word;
890
891 /*
892 * Is it a zlib-compressed buffer? If so, the first byte
893 * must be 0x78 (15-bit window size, deflated), and the
894 * first 16-bit word is evenly divisible by 31
895 */
896 word = (map[0] << 8) + map[1];
897 if (map[0] == 0x78 && !(word % 31))
898 return 1;
899 else
900 return 0;
901}
902
72518e9c 903unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep)
c4483576 904{
ad1ed5ee 905 unsigned shift;
93821bd9 906 unsigned char c;
93821bd9 907 unsigned long size;
ad1ed5ee
JH
908 unsigned long used = 0;
909
910 c = buf[used++];
911 *type = (c >> 4) & 7;
912 size = c & 15;
913 shift = 4;
914 while (c & 0x80) {
915 if (len <= used)
916 return 0;
917 if (sizeof(long) * 8 <= shift)
918 return 0;
919 c = buf[used++];
920 size += (c & 0x7f) << shift;
921 shift += 7;
922 }
923 *sizep = size;
924 return used;
925}
926
927static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
928{
929 unsigned long size, used;
930 static const char valid_loose_object_type[8] = {
931 0, /* OBJ_EXT */
932 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
933 0, /* "delta" and others are invalid in a loose object */
93821bd9 934 };
ad1ed5ee 935 enum object_type type;
93821bd9 936
c4483576
LT
937 /* Get the data stream */
938 memset(stream, 0, sizeof(*stream));
939 stream->next_in = map;
940 stream->avail_in = mapsize;
941 stream->next_out = buffer;
93821bd9
LT
942 stream->avail_out = bufsiz;
943
bb6b8e4f 944 if (legacy_loose_object(map)) {
93821bd9
LT
945 inflateInit(stream);
946 return inflate(stream, 0);
947 }
948
ad1ed5ee
JH
949 used = unpack_object_header_gently(map, mapsize, &type, &size);
950 if (!used || !valid_loose_object_type[type])
93821bd9 951 return -1;
ad1ed5ee
JH
952 map += used;
953 mapsize -= used;
93821bd9
LT
954
955 /* Set up the stream for the rest.. */
956 stream->next_in = map;
957 stream->avail_in = mapsize;
c4483576 958 inflateInit(stream);
93821bd9
LT
959
960 /* And generate the fake traditional header */
ad1ed5ee 961 stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
df843662 962 typename(type), size);
93821bd9 963 return 0;
c4483576
LT
964}
965
6da4016a 966static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size)
5180cacc
LT
967{
968 int bytes = strlen(buffer) + 1;
d565b341 969 unsigned char *buf = xmalloc(1+size);
93821bd9 970 unsigned long n;
5180cacc 971
93821bd9
LT
972 n = stream->total_out - bytes;
973 if (n > size)
974 n = size;
975 memcpy(buf, (char *) buffer + bytes, n);
976 bytes = n;
5180cacc
LT
977 if (bytes < size) {
978 stream->next_out = buf + bytes;
979 stream->avail_out = size - bytes;
980 while (inflate(stream, Z_FINISH) == Z_OK)
981 /* nothing */;
982 }
983 buf[size] = 0;
984 inflateEnd(stream);
985 return buf;
986}
987
988/*
989 * We used to just use "sscanf()", but that's actually way
990 * too permissive for what we want to check. So do an anal
991 * object header parse by hand.
992 */
21666f1a 993static int parse_sha1_header(const char *hdr, unsigned long *sizep)
5180cacc 994{
21666f1a 995 char type[10];
5180cacc
LT
996 int i;
997 unsigned long size;
998
999 /*
1000 * The type can be at most ten bytes (including the
1001 * terminating '\0' that we add), and is followed by
21666f1a 1002 * a space.
5180cacc 1003 */
21666f1a 1004 i = 0;
5180cacc
LT
1005 for (;;) {
1006 char c = *hdr++;
1007 if (c == ' ')
1008 break;
21666f1a
NP
1009 type[i++] = c;
1010 if (i >= sizeof(type))
5180cacc 1011 return -1;
5180cacc 1012 }
21666f1a 1013 type[i] = 0;
5180cacc
LT
1014
1015 /*
1016 * The length must follow immediately, and be in canonical
1017 * decimal format (ie "010" is not valid).
1018 */
1019 size = *hdr++ - '0';
1020 if (size > 9)
1021 return -1;
1022 if (size) {
1023 for (;;) {
1024 unsigned long c = *hdr - '0';
1025 if (c > 9)
1026 break;
1027 hdr++;
1028 size = size * 10 + c;
1029 }
1030 }
1031 *sizep = size;
1032
1033 /*
1034 * The length must be followed by a zero byte
1035 */
21666f1a 1036 return *hdr ? -1 : type_from_string(type);
5180cacc
LT
1037}
1038
21666f1a 1039void * unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size)
0fcfd160 1040{
5180cacc 1041 int ret;
0fcfd160 1042 z_stream stream;
5180cacc 1043 char hdr[8192];
0fcfd160 1044
5180cacc 1045 ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
21666f1a 1046 if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
0fcfd160
LT
1047 return NULL;
1048
5180cacc 1049 return unpack_sha1_rest(&stream, hdr, *size);
0fcfd160
LT
1050}
1051
c4001d92 1052static off_t get_delta_base(struct packed_git *p,
03e79c88 1053 struct pack_window **w_curs,
c4001d92 1054 off_t *curpos,
21666f1a 1055 enum object_type type,
c4001d92 1056 off_t delta_obj_offset)
eb32d236 1057{
2b87c45b 1058 unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
c4001d92 1059 off_t base_offset;
eb32d236 1060
8d8a4ea5
SP
1061 /* use_pack() assured us we have [base_info, base_info + 20)
1062 * as a range that we can look at without walking off the
1063 * end of the mapped window. Its actually the hash size
1064 * that is assured. An OFS_DELTA longer than the hash size
1065 * is stupid, as then a REF_DELTA would be smaller to store.
1066 */
21666f1a 1067 if (type == OBJ_OFS_DELTA) {
eb32d236
NP
1068 unsigned used = 0;
1069 unsigned char c = base_info[used++];
1070 base_offset = c & 127;
1071 while (c & 128) {
1072 base_offset += 1;
1073 if (!base_offset || base_offset & ~(~0UL >> 7))
1074 die("offset value overflow for delta base object");
1075 c = base_info[used++];
1076 base_offset = (base_offset << 7) + (c & 127);
1077 }
1078 base_offset = delta_obj_offset - base_offset;
1079 if (base_offset >= delta_obj_offset)
1080 die("delta base offset out of bound");
2b87c45b 1081 *curpos += used;
21666f1a 1082 } else if (type == OBJ_REF_DELTA) {
eb32d236
NP
1083 /* The base entry _must_ be in the same pack */
1084 base_offset = find_pack_entry_one(base_info, p);
1085 if (!base_offset)
1086 die("failed to find delta-pack base object %s",
1087 sha1_to_hex(base_info));
2b87c45b 1088 *curpos += 20;
eb32d236
NP
1089 } else
1090 die("I am totally screwed");
2b87c45b 1091 return base_offset;
eb32d236
NP
1092}
1093
f3bf9224 1094/* forward declaration for a mutually recursive function */
c4001d92 1095static int packed_object_info(struct packed_git *p, off_t offset,
21666f1a 1096 unsigned long *sizep);
f3bf9224 1097
43057304 1098static int packed_delta_info(struct packed_git *p,
03e79c88 1099 struct pack_window **w_curs,
c4001d92 1100 off_t curpos,
21666f1a 1101 enum object_type type,
c4001d92 1102 off_t obj_offset,
43057304 1103 unsigned long *sizep)
5db47c2b 1104{
c4001d92 1105 off_t base_offset;
f3bf9224 1106
21666f1a
NP
1107 base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
1108 type = packed_object_info(p, base_offset, NULL);
f3bf9224 1109
c62266f3
JH
1110 /* We choose to only get the type of the base object and
1111 * ignore potentially corrupt pack file that expects the delta
1112 * based on a base with a wrong size. This saves tons of
1113 * inflate() calls.
1114 */
c62266f3
JH
1115 if (sizep) {
1116 const unsigned char *data;
079afb18 1117 unsigned char delta_head[20], *in;
c62266f3
JH
1118 z_stream stream;
1119 int st;
1120
1121 memset(&stream, 0, sizeof(stream));
c62266f3
JH
1122 stream.next_out = delta_head;
1123 stream.avail_out = sizeof(delta_head);
1124
1125 inflateInit(&stream);
079afb18 1126 do {
2b87c45b 1127 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18
SP
1128 stream.next_in = in;
1129 st = inflate(&stream, Z_FINISH);
2b87c45b 1130 curpos += stream.next_in - in;
079afb18
SP
1131 } while ((st == Z_OK || st == Z_BUF_ERROR)
1132 && stream.total_out < sizeof(delta_head));
c62266f3
JH
1133 inflateEnd(&stream);
1134 if ((st != Z_STREAM_END) &&
1135 stream.total_out != sizeof(delta_head))
1136 die("delta data unpack-initial failed");
1137
1138 /* Examine the initial part of the delta to figure out
1139 * the result size.
1140 */
1141 data = delta_head;
8960844a
NP
1142
1143 /* ignore base size */
1144 get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
5db47c2b 1145
c62266f3 1146 /* Read the result size */
2b87c45b 1147 *sizep = get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
c62266f3 1148 }
21666f1a
NP
1149
1150 return type;
5db47c2b
JH
1151}
1152
2b87c45b
NP
1153static int unpack_object_header(struct packed_git *p,
1154 struct pack_window **w_curs,
c4001d92 1155 off_t *curpos,
2b87c45b 1156 unsigned long *sizep)
a733cb60 1157{
03e79c88
SP
1158 unsigned char *base;
1159 unsigned int left;
ad1ed5ee 1160 unsigned long used;
2b87c45b 1161 enum object_type type;
a733cb60 1162
8d8a4ea5
SP
1163 /* use_pack() assures us we have [base, base + 20) available
1164 * as a range that we can look at at. (Its actually the hash
3dff5379 1165 * size that is assured.) With our object header encoding
8d8a4ea5
SP
1166 * the maximum deflated object size is 2^137, which is just
1167 * insane, so we know won't exceed what we have been given.
1168 */
2b87c45b
NP
1169 base = use_pack(p, w_curs, *curpos, &left);
1170 used = unpack_object_header_gently(base, left, &type, sizep);
ad1ed5ee
JH
1171 if (!used)
1172 die("object offset outside of pack file");
2b87c45b 1173 *curpos += used;
ad1ed5ee 1174
2b87c45b 1175 return type;
a733cb60
LT
1176}
1177
21666f1a 1178const char *packed_object_info_detail(struct packed_git *p,
c4001d92 1179 off_t obj_offset,
21666f1a
NP
1180 unsigned long *size,
1181 unsigned long *store_size,
1182 unsigned int *delta_chain_length,
1183 unsigned char *base_sha1)
ad8c80a5 1184{
03e79c88 1185 struct pack_window *w_curs = NULL;
c4001d92
SP
1186 off_t curpos;
1187 unsigned long dummy;
43057304 1188 unsigned char *next_sha1;
21666f1a 1189 enum object_type type;
ad8c80a5 1190
43057304 1191 *delta_chain_length = 0;
2b87c45b 1192 curpos = obj_offset;
21666f1a 1193 type = unpack_object_header(p, &w_curs, &curpos, size);
43057304
NP
1194
1195 for (;;) {
21666f1a 1196 switch (type) {
43057304 1197 default:
08a19d87 1198 die("pack %s contains unknown object type %d",
21666f1a 1199 p->pack_name, type);
43057304
NP
1200 case OBJ_COMMIT:
1201 case OBJ_TREE:
1202 case OBJ_BLOB:
1203 case OBJ_TAG:
43057304 1204 *store_size = 0; /* notyet */
03e79c88 1205 unuse_pack(&w_curs);
21666f1a 1206 return typename(type);
eb32d236 1207 case OBJ_OFS_DELTA:
21666f1a 1208 obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
eb32d236 1209 if (*delta_chain_length == 0) {
2b87c45b 1210 /* TODO: find base_sha1 as pointed by curpos */
30fee062 1211 hashclr(base_sha1);
eb32d236
NP
1212 }
1213 break;
1214 case OBJ_REF_DELTA:
2b87c45b 1215 next_sha1 = use_pack(p, &w_curs, curpos, NULL);
43057304
NP
1216 if (*delta_chain_length == 0)
1217 hashcpy(base_sha1, next_sha1);
2b87c45b 1218 obj_offset = find_pack_entry_one(next_sha1, p);
43057304
NP
1219 break;
1220 }
43057304 1221 (*delta_chain_length)++;
2b87c45b 1222 curpos = obj_offset;
21666f1a 1223 type = unpack_object_header(p, &w_curs, &curpos, &dummy);
ad8c80a5 1224 }
ad8c80a5
JH
1225}
1226
c4001d92 1227static int packed_object_info(struct packed_git *p, off_t obj_offset,
21666f1a 1228 unsigned long *sizep)
1f688557 1229{
03e79c88 1230 struct pack_window *w_curs = NULL;
c4001d92
SP
1231 unsigned long size;
1232 off_t curpos = obj_offset;
21666f1a 1233 enum object_type type;
5db47c2b 1234
21666f1a 1235 type = unpack_object_header(p, &w_curs, &curpos, &size);
5db47c2b 1236
21666f1a 1237 switch (type) {
eb32d236
NP
1238 case OBJ_OFS_DELTA:
1239 case OBJ_REF_DELTA:
21666f1a
NP
1240 type = packed_delta_info(p, &w_curs, curpos,
1241 type, obj_offset, sizep);
2b87c45b 1242 break;
a733cb60 1243 case OBJ_COMMIT:
a733cb60 1244 case OBJ_TREE:
a733cb60 1245 case OBJ_BLOB:
a733cb60 1246 case OBJ_TAG:
2b87c45b
NP
1247 if (sizep)
1248 *sizep = size;
a69d0943 1249 break;
1f688557 1250 default:
08a19d87 1251 die("pack %s contains unknown object type %d",
21666f1a 1252 p->pack_name, type);
1f688557 1253 }
2b87c45b 1254 unuse_pack(&w_curs);
21666f1a 1255 return type;
1f688557
JH
1256}
1257
eb950c19 1258static void *unpack_compressed_entry(struct packed_git *p,
03e79c88 1259 struct pack_window **w_curs,
c4001d92 1260 off_t curpos,
eb950c19 1261 unsigned long size)
de530aaa
SP
1262{
1263 int st;
1264 z_stream stream;
079afb18 1265 unsigned char *buffer, *in;
de530aaa
SP
1266
1267 buffer = xmalloc(size + 1);
1268 buffer[size] = 0;
1269 memset(&stream, 0, sizeof(stream));
de530aaa
SP
1270 stream.next_out = buffer;
1271 stream.avail_out = size;
1272
1273 inflateInit(&stream);
079afb18 1274 do {
2b87c45b 1275 in = use_pack(p, w_curs, curpos, &stream.avail_in);
079afb18
SP
1276 stream.next_in = in;
1277 st = inflate(&stream, Z_FINISH);
2b87c45b 1278 curpos += stream.next_in - in;
079afb18 1279 } while (st == Z_OK || st == Z_BUF_ERROR);
de530aaa
SP
1280 inflateEnd(&stream);
1281 if ((st != Z_STREAM_END) || stream.total_out != size) {
1282 free(buffer);
1283 return NULL;
1284 }
1285
1286 return buffer;
1287}
1288
eb950c19 1289static void *unpack_delta_entry(struct packed_git *p,
03e79c88 1290 struct pack_window **w_curs,
c4001d92 1291 off_t curpos,
1f688557 1292 unsigned long delta_size,
c4001d92 1293 off_t obj_offset,
21666f1a 1294 enum object_type *type,
eb950c19 1295 unsigned long *sizep)
1f688557 1296{
7c3e8be3 1297 void *delta_data, *result, *base;
c4001d92
SP
1298 unsigned long base_size;
1299 off_t base_offset;
43057304 1300
21666f1a 1301 base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
4d703a1a 1302 base = unpack_entry(p, base_offset, type, &base_size);
67686d95 1303 if (!base)
c4001d92
SP
1304 die("failed to read delta base object"
1305 " at %"PRIuMAX" from %s",
1306 (uintmax_t)base_offset, p->pack_name);
67686d95 1307
2b87c45b 1308 delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size);
1f688557
JH
1309 result = patch_delta(base, base_size,
1310 delta_data, delta_size,
21666f1a 1311 sizep);
1f688557
JH
1312 if (!result)
1313 die("failed to apply delta");
1314 free(delta_data);
1315 free(base);
1f688557
JH
1316 return result;
1317}
1318
c4001d92 1319void *unpack_entry(struct packed_git *p, off_t obj_offset,
21666f1a 1320 enum object_type *type, unsigned long *sizep)
1f688557 1321{
03e79c88 1322 struct pack_window *w_curs = NULL;
c4001d92 1323 off_t curpos = obj_offset;
21666f1a 1324 void *data;
1f688557 1325
21666f1a
NP
1326 *type = unpack_object_header(p, &w_curs, &curpos, sizep);
1327 switch (*type) {
eb32d236
NP
1328 case OBJ_OFS_DELTA:
1329 case OBJ_REF_DELTA:
21666f1a
NP
1330 data = unpack_delta_entry(p, &w_curs, curpos, *sizep,
1331 obj_offset, type, sizep);
4d703a1a 1332 break;
a733cb60 1333 case OBJ_COMMIT:
a733cb60 1334 case OBJ_TREE:
a733cb60 1335 case OBJ_BLOB:
a733cb60 1336 case OBJ_TAG:
21666f1a 1337 data = unpack_compressed_entry(p, &w_curs, curpos, *sizep);
4d703a1a 1338 break;
1f688557 1339 default:
21666f1a 1340 die("unknown object type %i in %s", *type, p->pack_name);
1f688557 1341 }
03e79c88 1342 unuse_pack(&w_curs);
21666f1a 1343 return data;
1f688557
JH
1344}
1345
326bf396 1346uint32_t num_packed_objects(const struct packed_git *p)
9a217f2a 1347{
f9253394 1348 /* See check_packed_git_idx() */
9a217f2a
JH
1349 return (p->index_size - 20 - 20 - 4*256) / 24;
1350}
1351
326bf396 1352int nth_packed_object_sha1(const struct packed_git *p, uint32_t n,
9a217f2a
JH
1353 unsigned char* sha1)
1354{
1355 void *index = p->index_base + 256;
326bf396 1356 if (num_packed_objects(p) <= n)
9a217f2a 1357 return -1;
e702496e 1358 hashcpy(sha1, (unsigned char *) index + (24 * n) + 4);
9a217f2a
JH
1359 return 0;
1360}
1361
c4001d92 1362off_t find_pack_entry_one(const unsigned char *sha1,
43057304 1363 struct packed_git *p)
1f688557 1364{
b18b00a6 1365 uint32_t *level1_ofs = p->index_base;
1f688557
JH
1366 int hi = ntohl(level1_ofs[*sha1]);
1367 int lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
1368 void *index = p->index_base + 256;
1369
1370 do {
1371 int mi = (lo + hi) / 2;
a89fccd2 1372 int cmp = hashcmp((unsigned char *)index + (24 * mi) + 4, sha1);
43057304 1373 if (!cmp)
b18b00a6 1374 return ntohl(*((uint32_t *)((char *)index + (24 * mi))));
1f688557
JH
1375 if (cmp > 0)
1376 hi = mi;
1377 else
1378 lo = mi+1;
1379 } while (lo < hi);
1380 return 0;
1381}
1382
d4ff6d92
SP
1383static int matches_pack_name(struct packed_git *p, const char *ig)
1384{
1385 const char *last_c, *c;
1386
1387 if (!strcmp(p->pack_name, ig))
1388 return 0;
1389
1390 for (c = p->pack_name, last_c = c; *c;)
1391 if (*c == '/')
1392 last_c = ++c;
1393 else
1394 ++c;
1395 if (!strcmp(last_c, ig))
1396 return 0;
1397
1398 return 1;
1399}
1400
106d710b 1401static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e, const char **ignore_packed)
1f688557
JH
1402{
1403 struct packed_git *p;
c4001d92 1404 off_t offset;
43057304 1405
1f688557
JH
1406 prepare_packed_git();
1407
1408 for (p = packed_git; p; p = p->next) {
106d710b
JH
1409 if (ignore_packed) {
1410 const char **ig;
1411 for (ig = ignore_packed; *ig; ig++)
d4ff6d92 1412 if (!matches_pack_name(p, *ig))
106d710b
JH
1413 break;
1414 if (*ig)
1415 continue;
1416 }
43057304
NP
1417 offset = find_pack_entry_one(sha1, p);
1418 if (offset) {
c715f783
SP
1419 /*
1420 * We are about to tell the caller where they can
1421 * locate the requested object. We better make
1422 * sure the packfile is still here and can be
1423 * accessed before supplying that answer, as
1424 * it may have been deleted since the index
1425 * was loaded!
1426 */
1427 if (p->pack_fd == -1 && open_packed_git(p)) {
1428 error("packfile %s cannot be accessed", p->pack_name);
1429 continue;
1430 }
43057304
NP
1431 e->offset = offset;
1432 e->p = p;
1433 hashcpy(e->sha1, sha1);
1f688557 1434 return 1;
43057304 1435 }
1f688557
JH
1436 }
1437 return 0;
1438}
1439
bf592c50
DB
1440struct packed_git *find_sha1_pack(const unsigned char *sha1,
1441 struct packed_git *packs)
1442{
1443 struct packed_git *p;
bf592c50
DB
1444
1445 for (p = packs; p; p = p->next) {
43057304 1446 if (find_pack_entry_one(sha1, p))
bf592c50
DB
1447 return p;
1448 }
1449 return NULL;
21666f1a 1450
bf592c50
DB
1451}
1452
21666f1a 1453static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep)
65c2e0c3 1454{
36e4d74a 1455 int status;
65c2e0c3
JH
1456 unsigned long mapsize, size;
1457 void *map;
1458 z_stream stream;
d65a16f6 1459 char hdr[32];
65c2e0c3 1460
bb6b8e4f 1461 map = map_sha1_file(sha1, &mapsize);
f0df4ed5
JS
1462 if (!map)
1463 return error("unable to find %s", sha1_to_hex(sha1));
36e4d74a
JH
1464 if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
1465 status = error("unable to unpack %s header",
1466 sha1_to_hex(sha1));
21666f1a 1467 else if ((status = parse_sha1_header(hdr, &size)) < 0)
36e4d74a 1468 status = error("unable to parse %s header", sha1_to_hex(sha1));
21666f1a
NP
1469 else if (sizep)
1470 *sizep = size;
65c2e0c3
JH
1471 inflateEnd(&stream);
1472 munmap(map, mapsize);
1473 return status;
1474}
1475
21666f1a 1476int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
f0df4ed5 1477{
f0df4ed5
JS
1478 struct pack_entry e;
1479
1480 if (!find_pack_entry(sha1, &e, NULL)) {
1481 reprepare_packed_git();
1482 if (!find_pack_entry(sha1, &e, NULL))
21666f1a 1483 return sha1_loose_object_info(sha1, sizep);
f0df4ed5 1484 }
21666f1a 1485 return packed_object_info(e.p, e.offset, sizep);
f0df4ed5
JS
1486}
1487
21666f1a
NP
1488static void *read_packed_sha1(const unsigned char *sha1,
1489 enum object_type *type, unsigned long *size)
1f688557
JH
1490{
1491 struct pack_entry e;
1492
8276c007 1493 if (!find_pack_entry(sha1, &e, NULL))
1f688557 1494 return NULL;
8276c007
PE
1495 else
1496 return unpack_entry(e.p, e.offset, type, size);
1f688557
JH
1497}
1498
d66b37bb
JH
1499/*
1500 * This is meant to hold a *small* number of objects that you would
1501 * want read_sha1_file() to be able to return, but yet you do not want
1502 * to write them into the object store (e.g. a browse-only
1503 * application).
1504 */
1505static struct cached_object {
1506 unsigned char sha1[20];
21666f1a 1507 enum object_type type;
d66b37bb
JH
1508 void *buf;
1509 unsigned long size;
1510} *cached_objects;
1511static int cached_object_nr, cached_object_alloc;
1512
1513static struct cached_object *find_cached_object(const unsigned char *sha1)
1514{
1515 int i;
1516 struct cached_object *co = cached_objects;
1517
1518 for (i = 0; i < cached_object_nr; i++, co++) {
1519 if (!hashcmp(co->sha1, sha1))
1520 return co;
1521 }
1522 return NULL;
1523}
1524
21666f1a
NP
1525int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
1526 unsigned char *sha1)
d66b37bb
JH
1527{
1528 struct cached_object *co;
1529
21666f1a 1530 hash_sha1_file(buf, len, typename(type), sha1);
d66b37bb
JH
1531 if (has_sha1_file(sha1) || find_cached_object(sha1))
1532 return 0;
1533 if (cached_object_alloc <= cached_object_nr) {
1534 cached_object_alloc = alloc_nr(cached_object_alloc);
1535 cached_objects = xrealloc(cached_objects,
1536 sizeof(*cached_objects) *
1537 cached_object_alloc);
1538 }
1539 co = &cached_objects[cached_object_nr++];
1540 co->size = len;
21666f1a 1541 co->type = type;
efa13f7b
JH
1542 co->buf = xmalloc(len);
1543 memcpy(co->buf, buf, len);
d66b37bb
JH
1544 hashcpy(co->sha1, sha1);
1545 return 0;
1546}
1547
21666f1a
NP
1548void *read_sha1_file(const unsigned char *sha1, enum object_type *type,
1549 unsigned long *size)
0fcfd160
LT
1550{
1551 unsigned long mapsize;
1552 void *map, *buf;
d66b37bb
JH
1553 struct cached_object *co;
1554
1555 co = find_cached_object(sha1);
1556 if (co) {
1557 buf = xmalloc(co->size + 1);
1558 memcpy(buf, co->buf, co->size);
1559 ((char*)buf)[co->size] = 0;
21666f1a 1560 *type = co->type;
d66b37bb
JH
1561 *size = co->size;
1562 return buf;
1563 }
0fcfd160 1564
8276c007
PE
1565 buf = read_packed_sha1(sha1, type, size);
1566 if (buf)
1567 return buf;
bb6b8e4f 1568 map = map_sha1_file(sha1, &mapsize);
0fcfd160
LT
1569 if (map) {
1570 buf = unpack_sha1_file(map, mapsize, type, size);
1571 munmap(map, mapsize);
1572 return buf;
1573 }
637cdd9d 1574 reprepare_packed_git();
8276c007 1575 return read_packed_sha1(sha1, type, size);
0fcfd160
LT
1576}
1577
40469ee9 1578void *read_object_with_reference(const unsigned char *sha1,
21666f1a 1579 const char *required_type_name,
40469ee9
JH
1580 unsigned long *size,
1581 unsigned char *actual_sha1_return)
f4913f91 1582{
21666f1a 1583 enum object_type type, required_type;
f4913f91
JH
1584 void *buffer;
1585 unsigned long isize;
40469ee9 1586 unsigned char actual_sha1[20];
f4913f91 1587
21666f1a 1588 required_type = type_from_string(required_type_name);
e702496e 1589 hashcpy(actual_sha1, sha1);
40469ee9
JH
1590 while (1) {
1591 int ref_length = -1;
1592 const char *ref_type = NULL;
f4913f91 1593
21666f1a 1594 buffer = read_sha1_file(actual_sha1, &type, &isize);
40469ee9
JH
1595 if (!buffer)
1596 return NULL;
21666f1a 1597 if (type == required_type) {
40469ee9
JH
1598 *size = isize;
1599 if (actual_sha1_return)
e702496e 1600 hashcpy(actual_sha1_return, actual_sha1);
40469ee9
JH
1601 return buffer;
1602 }
1603 /* Handle references */
21666f1a 1604 else if (type == OBJ_COMMIT)
40469ee9 1605 ref_type = "tree ";
21666f1a 1606 else if (type == OBJ_TAG)
40469ee9
JH
1607 ref_type = "object ";
1608 else {
1609 free(buffer);
1610 return NULL;
1611 }
1612 ref_length = strlen(ref_type);
f4913f91 1613
40469ee9 1614 if (memcmp(buffer, ref_type, ref_length) ||
1d7f171c 1615 get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
40469ee9
JH
1616 free(buffer);
1617 return NULL;
1618 }
1cf58e72 1619 free(buffer);
40469ee9
JH
1620 /* Now we have the ID of the referred-to object in
1621 * actual_sha1. Check again. */
f4913f91 1622 }
f4913f91
JH
1623}
1624
972a9155
RS
1625static void write_sha1_file_prepare(void *buf, unsigned long len,
1626 const char *type, unsigned char *sha1,
d65a16f6 1627 char *hdr, int *hdrlen)
d410c0f5
JH
1628{
1629 SHA_CTX c;
1630
1631 /* Generate the header */
d65a16f6 1632 *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
d410c0f5
JH
1633
1634 /* Sha1.. */
1635 SHA1_Init(&c);
1636 SHA1_Update(&c, hdr, *hdrlen);
1637 SHA1_Update(&c, buf, len);
1638 SHA1_Final(sha1, &c);
d410c0f5
JH
1639}
1640
230f1322
LT
1641/*
1642 * Link the tempfile to the final place, possibly creating the
1643 * last directory level as you do so.
1644 *
1645 * Returns the errno on failure, 0 on success.
1646 */
839837b9 1647static int link_temp_to_file(const char *tmpfile, const char *filename)
230f1322
LT
1648{
1649 int ret;
756aaf4a 1650 char *dir;
230f1322
LT
1651
1652 if (!link(tmpfile, filename))
1653 return 0;
1654
1655 /*
756aaf4a 1656 * Try to mkdir the last path component if that failed.
230f1322
LT
1657 *
1658 * Re-try the "link()" regardless of whether the mkdir
1659 * succeeds, since a race might mean that somebody
1660 * else succeeded.
1661 */
1662 ret = errno;
756aaf4a
SP
1663 dir = strrchr(filename, '/');
1664 if (dir) {
1665 *dir = 0;
866cae0d 1666 if (!mkdir(filename, 0777) && adjust_shared_perm(filename)) {
91c23e48 1667 *dir = '/';
756aaf4a 1668 return -2;
91c23e48 1669 }
756aaf4a
SP
1670 *dir = '/';
1671 if (!link(tmpfile, filename))
1672 return 0;
1673 ret = errno;
230f1322
LT
1674 }
1675 return ret;
1676}
1677
1678/*
1679 * Move the just written object into its final resting place
1680 */
839837b9 1681int move_temp_to_file(const char *tmpfile, const char *filename)
230f1322
LT
1682{
1683 int ret = link_temp_to_file(tmpfile, filename);
7ebb6fca
LT
1684
1685 /*
1686 * Coda hack - coda doesn't like cross-directory links,
1687 * so we fall back to a rename, which will mean that it
1688 * won't be able to check collisions, but that's not a
1689 * big deal.
1690 *
1691 * The same holds for FAT formatted media.
1692 *
1693 * When this succeeds, we just return 0. We have nothing
1694 * left to unlink.
1695 */
1696 if (ret && ret != EEXIST) {
1697 if (!rename(tmpfile, filename))
230f1322 1698 return 0;
9e48b389 1699 ret = errno;
230f1322
LT
1700 }
1701 unlink(tmpfile);
1702 if (ret) {
1703 if (ret != EEXIST) {
916d081b 1704 return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret));
230f1322
LT
1705 }
1706 /* FIXME!!! Collision check here ? */
1707 }
1708
1709 return 0;
1710}
1711
4d548150
LT
1712static int write_buffer(int fd, const void *buf, size_t len)
1713{
d34cf19b 1714 if (write_in_full(fd, buf, len) < 0)
93822c22 1715 return error("file write error (%s)", strerror(errno));
4d548150
LT
1716 return 0;
1717}
1718
93821bd9
LT
1719static int write_binary_header(unsigned char *hdr, enum object_type type, unsigned long len)
1720{
1721 int hdr_len;
1722 unsigned char c;
1723
1724 c = (type << 4) | (len & 15);
1725 len >>= 4;
1726 hdr_len = 1;
1727 while (len) {
1728 *hdr++ = c | 0x80;
1729 hdr_len++;
1730 c = (len & 0x7f);
1731 len >>= 7;
1732 }
1733 *hdr = c;
1734 return hdr_len;
1735}
1736
1737static void setup_object_header(z_stream *stream, const char *type, unsigned long len)
1738{
d65a16f6 1739 int obj_type, hdrlen;
93821bd9
LT
1740
1741 if (use_legacy_headers) {
1742 while (deflate(stream, 0) == Z_OK)
1743 /* nothing */;
1744 return;
1745 }
df843662 1746 obj_type = type_from_string(type);
d65a16f6
NP
1747 hdrlen = write_binary_header(stream->next_out, obj_type, len);
1748 stream->total_out = hdrlen;
1749 stream->next_out += hdrlen;
1750 stream->avail_out -= hdrlen;
93821bd9
LT
1751}
1752
abdc3fc8
RS
1753int hash_sha1_file(void *buf, unsigned long len, const char *type,
1754 unsigned char *sha1)
1755{
d65a16f6 1756 char hdr[32];
abdc3fc8
RS
1757 int hdrlen;
1758 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1759 return 0;
1760}
1761
bf0f910d 1762int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
0fcfd160
LT
1763{
1764 int size;
bf0f910d 1765 unsigned char *compressed;
0fcfd160
LT
1766 z_stream stream;
1767 unsigned char sha1[20];
706bc531 1768 char *filename;
aac17941 1769 static char tmpfile[PATH_MAX];
d65a16f6 1770 char hdr[32];
230f1322 1771 int fd, hdrlen;
a44c9a5e 1772
d410c0f5
JH
1773 /* Normally if we have it in the pack then we do not bother writing
1774 * it out into .git/objects/??/?{38} file.
1775 */
972a9155
RS
1776 write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
1777 filename = sha1_file_name(sha1);
706bc531 1778 if (returnsha1)
e702496e 1779 hashcpy(returnsha1, sha1);
d410c0f5
JH
1780 if (has_sha1_file(sha1))
1781 return 0;
aac17941
LT
1782 fd = open(filename, O_RDONLY);
1783 if (fd >= 0) {
706bc531 1784 /*
aac17941
LT
1785 * FIXME!!! We might do collision checking here, but we'd
1786 * need to uncompress the old file and check it. Later.
706bc531 1787 */
aac17941 1788 close(fd);
706bc531
LT
1789 return 0;
1790 }
1791
aac17941 1792 if (errno != ENOENT) {
916d081b 1793 return error("sha1 file %s: %s\n", filename, strerror(errno));
aac17941
LT
1794 }
1795
1796 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
ace1534d 1797
aac17941
LT
1798 fd = mkstemp(tmpfile);
1799 if (fd < 0) {
916d081b
PB
1800 if (errno == EPERM)
1801 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
1802 else
1803 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
aac17941
LT
1804 }
1805
0fcfd160
LT
1806 /* Set it up */
1807 memset(&stream, 0, sizeof(stream));
12f6c308 1808 deflateInit(&stream, zlib_compression_level);
93821bd9 1809 size = 8 + deflateBound(&stream, len+hdrlen);
812666c8 1810 compressed = xmalloc(size);
0fcfd160
LT
1811
1812 /* Compress it */
0fcfd160
LT
1813 stream.next_out = compressed;
1814 stream.avail_out = size;
a44c9a5e
LT
1815
1816 /* First header.. */
d65a16f6 1817 stream.next_in = (unsigned char *)hdr;
a44c9a5e 1818 stream.avail_in = hdrlen;
93821bd9 1819 setup_object_header(&stream, type, len);
a44c9a5e
LT
1820
1821 /* Then the data itself.. */
1822 stream.next_in = buf;
1823 stream.avail_in = len;
0fcfd160
LT
1824 while (deflate(&stream, Z_FINISH) == Z_OK)
1825 /* nothing */;
1826 deflateEnd(&stream);
1827 size = stream.total_out;
1828
4d548150
LT
1829 if (write_buffer(fd, compressed, size) < 0)
1830 die("unable to write sha1 file");
aac17941 1831 fchmod(fd, 0444);
706bc531 1832 close(fd);
383f85b7 1833 free(compressed);
0fcfd160 1834
230f1322 1835 return move_temp_to_file(tmpfile, filename);
0fcfd160 1836}
8237b185 1837
4d548150
LT
1838/*
1839 * We need to unpack and recompress the object for writing
1840 * it out to a different file.
1841 */
1842static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
a5eda52b 1843{
4d548150 1844 size_t size;
a5eda52b 1845 z_stream stream;
4d548150
LT
1846 unsigned char *unpacked;
1847 unsigned long len;
21666f1a 1848 enum object_type type;
d65a16f6 1849 char hdr[32];
4d548150
LT
1850 int hdrlen;
1851 void *buf;
bfc66daf 1852
a9486b02 1853 /* need to unpack and recompress it by itself */
21666f1a 1854 unpacked = read_packed_sha1(sha1, &type, &len);
8276c007
PE
1855 if (!unpacked)
1856 error("cannot read sha1_file for %s", sha1_to_hex(sha1));
a5eda52b 1857
21666f1a 1858 hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
a5eda52b 1859
4d548150
LT
1860 /* Set it up */
1861 memset(&stream, 0, sizeof(stream));
12f6c308 1862 deflateInit(&stream, zlib_compression_level);
4d548150
LT
1863 size = deflateBound(&stream, len + hdrlen);
1864 buf = xmalloc(size);
a5eda52b 1865
4d548150
LT
1866 /* Compress it */
1867 stream.next_out = buf;
1868 stream.avail_out = size;
a5eda52b 1869
4d548150
LT
1870 /* First header.. */
1871 stream.next_in = (void *)hdr;
1872 stream.avail_in = hdrlen;
1873 while (deflate(&stream, 0) == Z_OK)
1874 /* nothing */;
bfc66daf 1875
4d548150
LT
1876 /* Then the data itself.. */
1877 stream.next_in = unpacked;
1878 stream.avail_in = len;
1879 while (deflate(&stream, Z_FINISH) == Z_OK)
1880 /* nothing */;
1881 deflateEnd(&stream);
1882 free(unpacked);
bfc66daf 1883
4d548150
LT
1884 *objsize = stream.total_out;
1885 return buf;
1886}
1887
1888int write_sha1_to_fd(int fd, const unsigned char *sha1)
1889{
1890 int retval;
1891 unsigned long objsize;
bb6b8e4f 1892 void *buf = map_sha1_file(sha1, &objsize);
4d548150
LT
1893
1894 if (buf) {
1895 retval = write_buffer(fd, buf, objsize);
1896 munmap(buf, objsize);
1897 return retval;
1898 }
1899
1900 buf = repack_object(sha1, &objsize);
1901 retval = write_buffer(fd, buf, objsize);
1902 free(buf);
1903 return retval;
a5eda52b
DB
1904}
1905
70b9829e
DB
1906int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
1907 size_t bufsize, size_t *bufposn)
8237b185 1908{
230f1322 1909 char tmpfile[PATH_MAX];
8237b185
DB
1910 int local;
1911 z_stream stream;
1912 unsigned char real_sha1[20];
bf0f910d 1913 unsigned char discard[4096];
8237b185
DB
1914 int ret;
1915 SHA_CTX c;
1916
230f1322 1917 snprintf(tmpfile, sizeof(tmpfile), "%s/obj_XXXXXX", get_object_directory());
8237b185 1918
230f1322 1919 local = mkstemp(tmpfile);
916d081b
PB
1920 if (local < 0) {
1921 if (errno == EPERM)
1922 return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
1923 else
1924 return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
1925 }
8237b185
DB
1926
1927 memset(&stream, 0, sizeof(stream));
1928
1929 inflateInit(&stream);
1930
1931 SHA1_Init(&c);
1932
1933 do {
1934 ssize_t size;
70b9829e
DB
1935 if (*bufposn) {
1936 stream.avail_in = *bufposn;
96ad15ae 1937 stream.next_in = (unsigned char *) buffer;
70b9829e
DB
1938 do {
1939 stream.next_out = discard;
1940 stream.avail_out = sizeof(discard);
1941 ret = inflate(&stream, Z_SYNC_FLUSH);
1942 SHA1_Update(&c, discard, sizeof(discard) -
1943 stream.avail_out);
1944 } while (stream.avail_in && ret == Z_OK);
4d548150
LT
1945 if (write_buffer(local, buffer, *bufposn - stream.avail_in) < 0)
1946 die("unable to write sha1 file");
70b9829e
DB
1947 memmove(buffer, buffer + *bufposn - stream.avail_in,
1948 stream.avail_in);
1949 *bufposn = stream.avail_in;
1950 if (ret != Z_OK)
1951 break;
1952 }
93d26e4c 1953 size = xread(fd, buffer + *bufposn, bufsize - *bufposn);
8237b185
DB
1954 if (size <= 0) {
1955 close(local);
230f1322 1956 unlink(tmpfile);
8237b185
DB
1957 if (!size)
1958 return error("Connection closed?");
1959 perror("Reading from connection");
1960 return -1;
1961 }
70b9829e
DB
1962 *bufposn += size;
1963 } while (1);
8237b185
DB
1964 inflateEnd(&stream);
1965
1966 close(local);
1967 SHA1_Final(real_sha1, &c);
1968 if (ret != Z_STREAM_END) {
230f1322 1969 unlink(tmpfile);
8237b185
DB
1970 return error("File %s corrupted", sha1_to_hex(sha1));
1971 }
a89fccd2 1972 if (hashcmp(sha1, real_sha1)) {
230f1322 1973 unlink(tmpfile);
bd2afde8 1974 return error("File %s has bad hash", sha1_to_hex(sha1));
8237b185 1975 }
230f1322
LT
1976
1977 return move_temp_to_file(tmpfile, sha1_file_name(sha1));
8237b185
DB
1978}
1979
bf592c50
DB
1980int has_pack_index(const unsigned char *sha1)
1981{
1982 struct stat st;
1983 if (stat(sha1_pack_index_name(sha1), &st))
1984 return 0;
1985 return 1;
1986}
1987
1988int has_pack_file(const unsigned char *sha1)
1989{
1990 struct stat st;
1991 if (stat(sha1_pack_name(sha1), &st))
1992 return 0;
1993 return 1;
1994}
1995
106d710b 1996int has_sha1_pack(const unsigned char *sha1, const char **ignore_packed)
dade09c2
LT
1997{
1998 struct pack_entry e;
106d710b 1999 return find_pack_entry(sha1, &e, ignore_packed);
dade09c2
LT
2000}
2001
8237b185
DB
2002int has_sha1_file(const unsigned char *sha1)
2003{
8237b185 2004 struct stat st;
1f688557
JH
2005 struct pack_entry e;
2006
106d710b 2007 if (find_pack_entry(sha1, &e, NULL))
1f688557 2008 return 1;
ab90ea5d 2009 return find_sha1_file(sha1, &st) ? 1 : 0;
8237b185 2010}
74400e71 2011
e7332f96
BE
2012/*
2013 * reads from fd as long as possible into a supplied buffer of size bytes.
82e5a82f 2014 * If necessary the buffer's size is increased using realloc()
e7332f96
BE
2015 *
2016 * returns 0 if anything went fine and -1 otherwise
2017 *
2018 * NOTE: both buf and size may change, but even when -1 is returned
2019 * you still have to free() it yourself.
2020 */
2021int read_pipe(int fd, char** return_buf, unsigned long* return_size)
024510c8 2022{
e7332f96
BE
2023 char* buf = *return_buf;
2024 unsigned long size = *return_size;
2025 int iret;
024510c8 2026 unsigned long off = 0;
e7332f96 2027
024510c8 2028 do {
e7332f96 2029 iret = xread(fd, buf + off, size - off);
024510c8
DB
2030 if (iret > 0) {
2031 off += iret;
2032 if (off == size) {
2033 size *= 2;
83572c1a 2034 buf = xrealloc(buf, size);
024510c8
DB
2035 }
2036 }
2037 } while (iret > 0);
e7332f96
BE
2038
2039 *return_buf = buf;
2040 *return_size = off;
2041
2042 if (iret < 0)
2043 return -1;
2044 return 0;
2045}
2046
2047int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
2048{
2049 unsigned long size = 4096;
2d7320d0 2050 char *buf = xmalloc(size);
e7332f96 2051 int ret;
e7332f96
BE
2052
2053 if (read_pipe(fd, &buf, &size)) {
024510c8
DB
2054 free(buf);
2055 return -1;
2056 }
e7332f96 2057
024510c8 2058 if (!type)
8e440259 2059 type = blob_type;
024510c8 2060 if (write_object)
e7332f96 2061 ret = write_sha1_file(buf, size, type, sha1);
abdc3fc8
RS
2062 else
2063 ret = hash_sha1_file(buf, size, type, sha1);
024510c8
DB
2064 free(buf);
2065 return ret;
2066}
2067
edaec3fb 2068int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object,
53bca91a 2069 enum object_type type, const char *path)
74400e71 2070{
74400e71 2071 unsigned long size = st->st_size;
3a55602e 2072 void *buf = NULL;
6c510bee 2073 int ret, re_allocated = 0;
74400e71 2074
74400e71 2075 if (size)
c4712e45 2076 buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
74400e71 2077 close(fd);
74400e71 2078
7672db20 2079 if (!type)
edaec3fb 2080 type = OBJ_BLOB;
6c510bee
LT
2081
2082 /*
2083 * Convert blobs to git internal format
2084 */
d0d8e14d 2085 if ((type == OBJ_BLOB) && S_ISREG(st->st_mode)) {
6c510bee
LT
2086 unsigned long nsize = size;
2087 char *nbuf = buf;
53bca91a 2088 if (convert_to_git(path, &nbuf, &nsize)) {
6c510bee
LT
2089 if (size)
2090 munmap(buf, size);
2091 size = nsize;
2092 buf = nbuf;
2093 re_allocated = 1;
2094 }
2095 }
2096
7672db20 2097 if (write_object)
edaec3fb 2098 ret = write_sha1_file(buf, size, typename(type), sha1);
abdc3fc8 2099 else
edaec3fb 2100 ret = hash_sha1_file(buf, size, typename(type), sha1);
6c510bee
LT
2101 if (re_allocated) {
2102 free(buf);
2103 return ret;
2104 }
aac17941
LT
2105 if (size)
2106 munmap(buf, size);
2107 return ret;
74400e71 2108}
ec1fcc16
JH
2109
2110int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
2111{
2112 int fd;
2113 char *target;
2114
2115 switch (st->st_mode & S_IFMT) {
2116 case S_IFREG:
2117 fd = open(path, O_RDONLY);
2118 if (fd < 0)
2119 return error("open(\"%s\"): %s", path,
2120 strerror(errno));
53bca91a 2121 if (index_fd(sha1, fd, st, write_object, OBJ_BLOB, path) < 0)
ec1fcc16
JH
2122 return error("%s: failed to insert into database",
2123 path);
2124 break;
2125 case S_IFLNK:
2126 target = xmalloc(st->st_size+1);
2127 if (readlink(path, target, st->st_size+1) != st->st_size) {
2128 char *errstr = strerror(errno);
2129 free(target);
2130 return error("readlink(\"%s\"): %s", path,
2131 errstr);
2132 }
abdc3fc8
RS
2133 if (!write_object)
2134 hash_sha1_file(target, st->st_size, blob_type, sha1);
2135 else if (write_sha1_file(target, st->st_size, blob_type, sha1))
ec1fcc16
JH
2136 return error("%s: failed to insert into database",
2137 path);
2138 free(target);
2139 break;
2140 default:
2141 return error("%s: unsupported file type", path);
2142 }
2143 return 0;
2144}
a69e5429
JH
2145
2146int read_pack_header(int fd, struct pack_header *header)
2147{
2148 char *c = (char*)header;
2149 ssize_t remaining = sizeof(struct pack_header);
2150 do {
2151 ssize_t r = xread(fd, c, remaining);
2152 if (r <= 0)
2153 /* "eof before pack header was fully read" */
2154 return PH_ERROR_EOF;
2155 remaining -= r;
2156 c += r;
2157 } while (remaining > 0);
2158 if (header->hdr_signature != htonl(PACK_SIGNATURE))
2159 /* "protocol error (pack signature mismatch detected)" */
2160 return PH_ERROR_PACK_SIGNATURE;
2161 if (!pack_version_ok(header->hdr_version))
2162 /* "protocol error (pack version unsupported)" */
2163 return PH_ERROR_PROTOCOL;
2164 return 0;
2165}