Merge branch 'np/pack'
[git/git.git] / index-pack.c
CommitLineData
9cf6d335
SV
1#include "cache.h"
2#include "delta.h"
3#include "pack.h"
4#include "csum-file.h"
8e440259
PE
5#include "blob.h"
6#include "commit.h"
7#include "tag.h"
8#include "tree.h"
96a02f8f 9#include "progress.h"
9cf6d335
SV
10
11static const char index_pack_usage[] =
b8077709 12"git-index-pack [-v] [-o <index-file>] [{ ---keep | --keep=<msg> }] { <pack-file> | --stdin [--fix-thin] [<pack-file>] }";
9cf6d335
SV
13
14struct object_entry
15{
d7dd0223 16 off_t offset;
2d477051
NP
17 unsigned long size;
18 unsigned int hdr_size;
ee5743ce 19 uint32_t crc32;
9cf6d335
SV
20 enum object_type type;
21 enum object_type real_type;
22 unsigned char sha1[20];
23};
24
53dda6ff
NP
25union delta_base {
26 unsigned char sha1[20];
d7dd0223 27 off_t offset;
53dda6ff
NP
28};
29
3c552873
NP
30/*
31 * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
32 * to memcmp() only the first 20 bytes.
33 */
34#define UNION_BASE_SZ 20
35
9cf6d335
SV
36struct delta_entry
37{
53dda6ff 38 union delta_base base;
636171cb 39 int obj_no;
9cf6d335
SV
40};
41
9cf6d335
SV
42static struct object_entry *objects;
43static struct delta_entry *deltas;
44static int nr_objects;
45static int nr_deltas;
636171cb 46static int nr_resolved_deltas;
9cf6d335 47
e42797f5 48static int from_stdin;
3c9af366
NP
49static int verbose;
50
96a02f8f 51static struct progress progress;
e42797f5 52
2d477051
NP
53/* We always read in 4kB chunks. */
54static unsigned char input_buffer[4096];
d7dd0223
NP
55static unsigned int input_offset, input_len;
56static off_t consumed_bytes;
2d477051 57static SHA_CTX input_ctx;
ee5743ce 58static uint32_t input_crc32;
6d2fa7f1 59static int input_fd, output_fd, pack_fd;
2d477051 60
636171cb 61/* Discard current buffer used content. */
a6e8a767 62static void flush(void)
636171cb
NP
63{
64 if (input_offset) {
65 if (output_fd >= 0)
66 write_or_die(output_fd, input_buffer, input_offset);
67 SHA1_Update(&input_ctx, input_buffer, input_offset);
554a2636 68 memmove(input_buffer, input_buffer + input_offset, input_len);
636171cb
NP
69 input_offset = 0;
70 }
71}
72
2d477051
NP
73/*
74 * Make sure at least "min" bytes are available in the buffer, and
75 * return the pointer to the buffer.
76 */
b89c4e93 77static void *fill(int min)
9cf6d335 78{
2d477051
NP
79 if (min <= input_len)
80 return input_buffer + input_offset;
81 if (min > sizeof(input_buffer))
82 die("cannot fill %d bytes", min);
636171cb 83 flush();
2d477051 84 do {
8a912bcb 85 ssize_t ret = xread(input_fd, input_buffer + input_len,
2d477051
NP
86 sizeof(input_buffer) - input_len);
87 if (ret <= 0) {
88 if (!ret)
89 die("early EOF");
90 die("read error on input: %s", strerror(errno));
91 }
92 input_len += ret;
93 } while (input_len < min);
94 return input_buffer;
95}
96
97static void use(int bytes)
98{
99 if (bytes > input_len)
100 die("used more bytes than were available");
ee5743ce 101 input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
2d477051
NP
102 input_len -= bytes;
103 input_offset += bytes;
d7dd0223
NP
104
105 /* make sure off_t is sufficiently large not to wrap */
106 if (consumed_bytes > consumed_bytes + bytes)
107 die("pack too large for current definition of off_t");
2d477051
NP
108 consumed_bytes += bytes;
109}
9cf6d335 110
b89c4e93 111static const char *open_pack_file(const char *pack_name)
2d477051 112{
e42797f5
NP
113 if (from_stdin) {
114 input_fd = 0;
115 if (!pack_name) {
116 static char tmpfile[PATH_MAX];
117 snprintf(tmpfile, sizeof(tmpfile),
0e55181f 118 "%s/tmp_pack_XXXXXX", get_object_directory());
e42797f5
NP
119 output_fd = mkstemp(tmpfile);
120 pack_name = xstrdup(tmpfile);
121 } else
122 output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
123 if (output_fd < 0)
124 die("unable to create %s: %s\n", pack_name, strerror(errno));
6d2fa7f1 125 pack_fd = output_fd;
e42797f5
NP
126 } else {
127 input_fd = open(pack_name, O_RDONLY);
128 if (input_fd < 0)
129 die("cannot open packfile '%s': %s",
130 pack_name, strerror(errno));
131 output_fd = -1;
6d2fa7f1 132 pack_fd = input_fd;
e42797f5 133 }
2d477051 134 SHA1_Init(&input_ctx);
e42797f5 135 return pack_name;
9cf6d335
SV
136}
137
138static void parse_pack_header(void)
139{
2d477051 140 struct pack_header *hdr = fill(sizeof(struct pack_header));
9cf6d335
SV
141
142 /* Header consistency check */
9cf6d335 143 if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
e42797f5 144 die("pack signature mismatch");
d60fc1c8 145 if (!pack_version_ok(hdr->hdr_version))
e42797f5 146 die("pack version %d unsupported", ntohl(hdr->hdr_version));
9cf6d335
SV
147
148 nr_objects = ntohl(hdr->hdr_entries);
2d477051 149 use(sizeof(struct pack_header));
9cf6d335
SV
150}
151
152static void bad_object(unsigned long offset, const char *format,
153 ...) NORETURN __attribute__((format (printf, 2, 3)));
154
155static void bad_object(unsigned long offset, const char *format, ...)
156{
157 va_list params;
158 char buf[1024];
159
160 va_start(params, format);
161 vsnprintf(buf, sizeof(buf), format, params);
162 va_end(params);
e42797f5 163 die("pack has bad object at offset %lu: %s", offset, buf);
9cf6d335
SV
164}
165
2d477051 166static void *unpack_entry_data(unsigned long offset, unsigned long size)
9cf6d335 167{
9cf6d335
SV
168 z_stream stream;
169 void *buf = xmalloc(size);
170
171 memset(&stream, 0, sizeof(stream));
172 stream.next_out = buf;
173 stream.avail_out = size;
2d477051
NP
174 stream.next_in = fill(1);
175 stream.avail_in = input_len;
9cf6d335
SV
176 inflateInit(&stream);
177
178 for (;;) {
179 int ret = inflate(&stream, 0);
2d477051
NP
180 use(input_len - stream.avail_in);
181 if (stream.total_out == size && ret == Z_STREAM_END)
9cf6d335
SV
182 break;
183 if (ret != Z_OK)
184 bad_object(offset, "inflate returned %d", ret);
2d477051
NP
185 stream.next_in = fill(1);
186 stream.avail_in = input_len;
9cf6d335
SV
187 }
188 inflateEnd(&stream);
9cf6d335
SV
189 return buf;
190}
191
2d477051 192static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_base)
9cf6d335 193{
2d477051 194 unsigned char *p, c;
d7dd0223
NP
195 unsigned long size;
196 off_t base_offset;
9cf6d335 197 unsigned shift;
ee5743ce 198 void *data;
9cf6d335 199
2d477051 200 obj->offset = consumed_bytes;
ee5743ce 201 input_crc32 = crc32(0, Z_NULL, 0);
2d477051
NP
202
203 p = fill(1);
204 c = *p;
205 use(1);
206 obj->type = (c >> 4) & 7;
9cf6d335
SV
207 size = (c & 15);
208 shift = 4;
209 while (c & 0x80) {
2d477051
NP
210 p = fill(1);
211 c = *p;
212 use(1);
9cf6d335
SV
213 size += (c & 0x7fUL) << shift;
214 shift += 7;
215 }
2d477051 216 obj->size = size;
9cf6d335 217
2d477051 218 switch (obj->type) {
eb32d236 219 case OBJ_REF_DELTA:
2d477051
NP
220 hashcpy(delta_base->sha1, fill(20));
221 use(20);
53dda6ff
NP
222 break;
223 case OBJ_OFS_DELTA:
224 memset(delta_base, 0, sizeof(*delta_base));
2d477051
NP
225 p = fill(1);
226 c = *p;
227 use(1);
53dda6ff
NP
228 base_offset = c & 127;
229 while (c & 128) {
230 base_offset += 1;
8723f216 231 if (!base_offset || MSB(base_offset, 7))
2d477051
NP
232 bad_object(obj->offset, "offset value overflow for delta base object");
233 p = fill(1);
234 c = *p;
235 use(1);
53dda6ff
NP
236 base_offset = (base_offset << 7) + (c & 127);
237 }
2d477051
NP
238 delta_base->offset = obj->offset - base_offset;
239 if (delta_base->offset >= obj->offset)
240 bad_object(obj->offset, "delta base offset is out of bound");
53dda6ff 241 break;
9cf6d335
SV
242 case OBJ_COMMIT:
243 case OBJ_TREE:
244 case OBJ_BLOB:
245 case OBJ_TAG:
9cf6d335
SV
246 break;
247 default:
08a19d87 248 bad_object(obj->offset, "unknown object type %d", obj->type);
9cf6d335 249 }
2d477051
NP
250 obj->hdr_size = consumed_bytes - obj->offset;
251
ee5743ce
NP
252 data = unpack_entry_data(obj->offset, obj->size);
253 obj->crc32 = input_crc32;
254 return data;
2d477051
NP
255}
256
b89c4e93 257static void *get_data_from_pack(struct object_entry *obj)
2d477051
NP
258{
259 unsigned long from = obj[0].offset + obj[0].hdr_size;
260 unsigned long len = obj[1].offset - from;
a91d49cd 261 unsigned long rdy = 0;
6d2fa7f1 262 unsigned char *src, *data;
2d477051
NP
263 z_stream stream;
264 int st;
9cf6d335 265
6d2fa7f1 266 src = xmalloc(len);
a91d49cd
SP
267 data = src;
268 do {
269 ssize_t n = pread(pack_fd, data + rdy, len - rdy, from + rdy);
270 if (n <= 0)
271 die("cannot pread pack file: %s", strerror(errno));
272 rdy += n;
273 } while (rdy < len);
2d477051
NP
274 data = xmalloc(obj->size);
275 memset(&stream, 0, sizeof(stream));
276 stream.next_out = data;
277 stream.avail_out = obj->size;
6d2fa7f1 278 stream.next_in = src;
2d477051
NP
279 stream.avail_in = len;
280 inflateInit(&stream);
281 while ((st = inflate(&stream, Z_FINISH)) == Z_OK);
282 inflateEnd(&stream);
283 if (st != Z_STREAM_END || stream.total_out != obj->size)
284 die("serious inflate inconsistency");
6d2fa7f1 285 free(src);
9cf6d335
SV
286 return data;
287}
288
53dda6ff 289static int find_delta(const union delta_base *base)
9cf6d335
SV
290{
291 int first = 0, last = nr_deltas;
292
293 while (first < last) {
294 int next = (first + last) / 2;
295 struct delta_entry *delta = &deltas[next];
296 int cmp;
297
3c552873 298 cmp = memcmp(base, &delta->base, UNION_BASE_SZ);
9cf6d335
SV
299 if (!cmp)
300 return next;
301 if (cmp < 0) {
302 last = next;
303 continue;
304 }
305 first = next+1;
306 }
307 return -first-1;
308}
309
b89c4e93
NP
310static int find_delta_children(const union delta_base *base,
311 int *first_index, int *last_index)
9cf6d335 312{
53dda6ff 313 int first = find_delta(base);
9cf6d335
SV
314 int last = first;
315 int end = nr_deltas - 1;
316
317 if (first < 0)
318 return -1;
3c552873 319 while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
9cf6d335 320 --first;
3c552873 321 while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
9cf6d335
SV
322 ++last;
323 *first_index = first;
324 *last_index = last;
325 return 0;
326}
327
328static void sha1_object(const void *data, unsigned long size,
9096c660 329 enum object_type type, unsigned char *sha1)
9cf6d335 330{
ce9fbf16 331 hash_sha1_file(data, size, typename(type), sha1);
9096c660 332 if (has_sha1_file(sha1)) {
8685da42
NP
333 void *has_data;
334 enum object_type has_type;
335 unsigned long has_size;
336 has_data = read_sha1_file(sha1, &has_type, &has_size);
337 if (!has_data)
338 die("cannot read existing object %s", sha1_to_hex(sha1));
339 if (size != has_size || type != has_type ||
340 memcmp(data, has_data, size) != 0)
341 die("SHA1 COLLISION FOUND WITH %s !", sha1_to_hex(sha1));
bbf4b41b 342 free(has_data);
8685da42 343 }
9cf6d335
SV
344}
345
636171cb 346static void resolve_delta(struct object_entry *delta_obj, void *base_data,
9cf6d335
SV
347 unsigned long base_size, enum object_type type)
348{
9cf6d335
SV
349 void *delta_data;
350 unsigned long delta_size;
351 void *result;
352 unsigned long result_size;
53dda6ff 353 union delta_base delta_base;
9cf6d335
SV
354 int j, first, last;
355
636171cb
NP
356 delta_obj->real_type = type;
357 delta_data = get_data_from_pack(delta_obj);
358 delta_size = delta_obj->size;
9cf6d335
SV
359 result = patch_delta(base_data, base_size, delta_data, delta_size,
360 &result_size);
361 free(delta_data);
362 if (!result)
636171cb 363 bad_object(delta_obj->offset, "failed to apply delta");
9096c660 364 sha1_object(result, result_size, type, delta_obj->sha1);
636171cb 365 nr_resolved_deltas++;
53dda6ff 366
636171cb 367 hashcpy(delta_base.sha1, delta_obj->sha1);
b89c4e93 368 if (!find_delta_children(&delta_base, &first, &last)) {
636171cb
NP
369 for (j = first; j <= last; j++) {
370 struct object_entry *child = objects + deltas[j].obj_no;
371 if (child->real_type == OBJ_REF_DELTA)
372 resolve_delta(child, result, result_size, type);
373 }
53dda6ff
NP
374 }
375
376 memset(&delta_base, 0, sizeof(delta_base));
636171cb 377 delta_base.offset = delta_obj->offset;
b89c4e93 378 if (!find_delta_children(&delta_base, &first, &last)) {
636171cb
NP
379 for (j = first; j <= last; j++) {
380 struct object_entry *child = objects + deltas[j].obj_no;
381 if (child->real_type == OBJ_OFS_DELTA)
382 resolve_delta(child, result, result_size, type);
383 }
9cf6d335 384 }
53dda6ff 385
9cf6d335
SV
386 free(result);
387}
388
389static int compare_delta_entry(const void *a, const void *b)
390{
391 const struct delta_entry *delta_a = a;
392 const struct delta_entry *delta_b = b;
3c552873 393 return memcmp(&delta_a->base, &delta_b->base, UNION_BASE_SZ);
9cf6d335
SV
394}
395
2d477051
NP
396/* Parse all objects and return the pack content SHA1 hash */
397static void parse_pack_objects(unsigned char *sha1)
9cf6d335 398{
96a02f8f 399 int i;
53dda6ff 400 struct delta_entry *delta = deltas;
9cf6d335 401 void *data;
2d477051 402 struct stat st;
9cf6d335
SV
403
404 /*
405 * First pass:
406 * - find locations of all objects;
407 * - calculate SHA1 of all non-delta objects;
b89c4e93 408 * - remember base (SHA1 or offset) for all deltas.
9cf6d335 409 */
13aaf148
NP
410 if (verbose)
411 start_progress(&progress, "Indexing %u objects...", "", nr_objects);
9cf6d335
SV
412 for (i = 0; i < nr_objects; i++) {
413 struct object_entry *obj = &objects[i];
2d477051 414 data = unpack_raw_entry(obj, &delta->base);
9cf6d335 415 obj->real_type = obj->type;
53dda6ff
NP
416 if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
417 nr_deltas++;
636171cb 418 delta->obj_no = i;
53dda6ff 419 delta++;
9cf6d335 420 } else
9096c660 421 sha1_object(data, obj->size, obj->type, obj->sha1);
9cf6d335 422 free(data);
3c9af366 423 if (verbose)
96a02f8f 424 display_progress(&progress, i+1);
9cf6d335 425 }
2d477051 426 objects[i].offset = consumed_bytes;
3c9af366 427 if (verbose)
96a02f8f 428 stop_progress(&progress);
2d477051
NP
429
430 /* Check pack integrity */
636171cb 431 flush();
2d477051
NP
432 SHA1_Final(sha1, &input_ctx);
433 if (hashcmp(fill(20), sha1))
e42797f5 434 die("pack is corrupted (SHA1 mismatch)");
9bee2478 435 use(20);
2d477051
NP
436
437 /* If input_fd is a file, we should have reached its end now. */
438 if (fstat(input_fd, &st))
e42797f5 439 die("cannot fstat packfile: %s", strerror(errno));
fa257b05
JS
440 if (S_ISREG(st.st_mode) &&
441 lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
e42797f5 442 die("pack has junk at the end");
9cf6d335 443
3c9af366
NP
444 if (!nr_deltas)
445 return;
446
53dda6ff 447 /* Sort deltas by base SHA1/offset for fast searching */
9cf6d335
SV
448 qsort(deltas, nr_deltas, sizeof(struct delta_entry),
449 compare_delta_entry);
450
451 /*
452 * Second pass:
453 * - for all non-delta objects, look if it is used as a base for
454 * deltas;
455 * - if used as a base, uncompress the object and apply all deltas,
456 * recursively checking if the resulting object is used as a base
457 * for some more deltas.
458 */
13aaf148
NP
459 if (verbose)
460 start_progress(&progress, "Resolving %u deltas...", "", nr_deltas);
9cf6d335
SV
461 for (i = 0; i < nr_objects; i++) {
462 struct object_entry *obj = &objects[i];
53dda6ff
NP
463 union delta_base base;
464 int j, ref, ref_first, ref_last, ofs, ofs_first, ofs_last;
9cf6d335 465
53dda6ff 466 if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA)
9cf6d335 467 continue;
53dda6ff 468 hashcpy(base.sha1, obj->sha1);
b89c4e93 469 ref = !find_delta_children(&base, &ref_first, &ref_last);
53dda6ff
NP
470 memset(&base, 0, sizeof(base));
471 base.offset = obj->offset;
b89c4e93 472 ofs = !find_delta_children(&base, &ofs_first, &ofs_last);
53dda6ff 473 if (!ref && !ofs)
9cf6d335 474 continue;
2d477051 475 data = get_data_from_pack(obj);
53dda6ff 476 if (ref)
636171cb
NP
477 for (j = ref_first; j <= ref_last; j++) {
478 struct object_entry *child = objects + deltas[j].obj_no;
479 if (child->real_type == OBJ_REF_DELTA)
480 resolve_delta(child, data,
2d477051 481 obj->size, obj->type);
636171cb 482 }
53dda6ff 483 if (ofs)
636171cb
NP
484 for (j = ofs_first; j <= ofs_last; j++) {
485 struct object_entry *child = objects + deltas[j].obj_no;
486 if (child->real_type == OBJ_OFS_DELTA)
487 resolve_delta(child, data,
2d477051 488 obj->size, obj->type);
636171cb 489 }
9cf6d335 490 free(data);
3c9af366 491 if (verbose)
96a02f8f 492 display_progress(&progress, nr_resolved_deltas);
9cf6d335 493 }
636171cb
NP
494}
495
ee5743ce 496static int write_compressed(int fd, void *in, unsigned int size, uint32_t *obj_crc)
636171cb
NP
497{
498 z_stream stream;
499 unsigned long maxsize;
500 void *out;
501
502 memset(&stream, 0, sizeof(stream));
503 deflateInit(&stream, zlib_compression_level);
504 maxsize = deflateBound(&stream, size);
505 out = xmalloc(maxsize);
506
507 /* Compress it */
508 stream.next_in = in;
509 stream.avail_in = size;
510 stream.next_out = out;
511 stream.avail_out = maxsize;
512 while (deflate(&stream, Z_FINISH) == Z_OK);
513 deflateEnd(&stream);
514
515 size = stream.total_out;
516 write_or_die(fd, out, size);
ee5743ce 517 *obj_crc = crc32(*obj_crc, out, size);
636171cb
NP
518 free(out);
519 return size;
520}
521
9096c660 522static void append_obj_to_pack(const unsigned char *sha1, void *buf,
636171cb
NP
523 unsigned long size, enum object_type type)
524{
525 struct object_entry *obj = &objects[nr_objects++];
526 unsigned char header[10];
527 unsigned long s = size;
528 int n = 0;
529 unsigned char c = (type << 4) | (s & 15);
530 s >>= 4;
531 while (s) {
532 header[n++] = c | 0x80;
533 c = s & 0x7f;
534 s >>= 7;
535 }
536 header[n++] = c;
537 write_or_die(output_fd, header, n);
ee5743ce
NP
538 obj[0].crc32 = crc32(0, Z_NULL, 0);
539 obj[0].crc32 = crc32(obj[0].crc32, header, n);
636171cb 540 obj[1].offset = obj[0].offset + n;
ee5743ce 541 obj[1].offset += write_compressed(output_fd, buf, size, &obj[0].crc32);
9096c660 542 hashcpy(obj->sha1, sha1);
636171cb
NP
543}
544
545static int delta_pos_compare(const void *_a, const void *_b)
546{
547 struct delta_entry *a = *(struct delta_entry **)_a;
548 struct delta_entry *b = *(struct delta_entry **)_b;
549 return a->obj_no - b->obj_no;
550}
9cf6d335 551
636171cb
NP
552static void fix_unresolved_deltas(int nr_unresolved)
553{
554 struct delta_entry **sorted_by_pos;
96a02f8f 555 int i, n = 0;
636171cb
NP
556
557 /*
558 * Since many unresolved deltas may well be themselves base objects
559 * for more unresolved deltas, we really want to include the
560 * smallest number of base objects that would cover as much delta
561 * as possible by picking the
562 * trunc deltas first, allowing for other deltas to resolve without
563 * additional base objects. Since most base objects are to be found
564 * before deltas depending on them, a good heuristic is to start
565 * resolving deltas in the same order as their position in the pack.
566 */
567 sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
9cf6d335 568 for (i = 0; i < nr_deltas; i++) {
636171cb
NP
569 if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
570 continue;
571 sorted_by_pos[n++] = &deltas[i];
9cf6d335 572 }
636171cb
NP
573 qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
574
575 for (i = 0; i < n; i++) {
576 struct delta_entry *d = sorted_by_pos[i];
577 void *data;
578 unsigned long size;
21666f1a 579 enum object_type type;
636171cb
NP
580 int j, first, last;
581
582 if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
583 continue;
21666f1a 584 data = read_sha1_file(d->base.sha1, &type, &size);
636171cb
NP
585 if (!data)
586 continue;
636171cb 587
b89c4e93 588 find_delta_children(&d->base, &first, &last);
636171cb
NP
589 for (j = first; j <= last; j++) {
590 struct object_entry *child = objects + deltas[j].obj_no;
591 if (child->real_type == OBJ_REF_DELTA)
21666f1a 592 resolve_delta(child, data, size, type);
636171cb
NP
593 }
594
9096c660
NP
595 if (check_sha1_signature(d->base.sha1, data, size, typename(type)))
596 die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
597 append_obj_to_pack(d->base.sha1, data, size, type);
636171cb 598 free(data);
3c9af366 599 if (verbose)
96a02f8f 600 display_progress(&progress, nr_resolved_deltas);
636171cb
NP
601 }
602 free(sorted_by_pos);
603}
604
4ba7d711
NP
605static uint32_t index_default_version = 1;
606static uint32_t index_off32_limit = 0x7fffffff;
607
9cf6d335
SV
608static int sha1_compare(const void *_a, const void *_b)
609{
610 struct object_entry *a = *(struct object_entry **)_a;
611 struct object_entry *b = *(struct object_entry **)_b;
a89fccd2 612 return hashcmp(a->sha1, b->sha1);
9cf6d335
SV
613}
614
2d477051
NP
615/*
616 * On entry *sha1 contains the pack content SHA1 hash, on exit it is
617 * the SHA1 hash of sorted object names.
618 */
b89c4e93 619static const char *write_index_file(const char *index_name, unsigned char *sha1)
9cf6d335
SV
620{
621 struct sha1file *f;
7e4a2a84 622 struct object_entry **sorted_by_sha, **list, **last;
d1a46a9e 623 uint32_t array[256];
e42797f5 624 int i, fd;
84c8d8ae 625 SHA_CTX ctx;
d1a46a9e 626 uint32_t index_version;
9cf6d335 627
7e4a2a84
JH
628 if (nr_objects) {
629 sorted_by_sha =
630 xcalloc(nr_objects, sizeof(struct object_entry *));
631 list = sorted_by_sha;
632 last = sorted_by_sha + nr_objects;
633 for (i = 0; i < nr_objects; ++i)
634 sorted_by_sha[i] = &objects[i];
635 qsort(sorted_by_sha, nr_objects, sizeof(sorted_by_sha[0]),
636 sha1_compare);
7e4a2a84
JH
637 }
638 else
639 sorted_by_sha = list = last = NULL;
9cf6d335 640
e42797f5
NP
641 if (!index_name) {
642 static char tmpfile[PATH_MAX];
643 snprintf(tmpfile, sizeof(tmpfile),
0e55181f 644 "%s/tmp_idx_XXXXXX", get_object_directory());
e42797f5
NP
645 fd = mkstemp(tmpfile);
646 index_name = xstrdup(tmpfile);
647 } else {
648 unlink(index_name);
649 fd = open(index_name, O_CREAT|O_EXCL|O_WRONLY, 0600);
650 }
651 if (fd < 0)
652 die("unable to create %s: %s", index_name, strerror(errno));
653 f = sha1fd(fd, index_name);
9cf6d335 654
d1a46a9e 655 /* if last object's offset is >= 2^31 we should use index V2 */
4ba7d711 656 index_version = (objects[nr_objects-1].offset >> 31) ? 2 : index_default_version;
d1a46a9e
NP
657
658 /* index versions 2 and above need a header */
659 if (index_version >= 2) {
660 struct pack_idx_header hdr;
661 hdr.idx_signature = htonl(PACK_IDX_SIGNATURE);
662 hdr.idx_version = htonl(index_version);
663 sha1write(f, &hdr, sizeof(hdr));
664 }
665
9cf6d335
SV
666 /*
667 * Write the first-level table (the list is sorted,
668 * but we use a 256-entry lookup to be able to avoid
669 * having to do eight extra binary search iterations).
670 */
671 for (i = 0; i < 256; i++) {
672 struct object_entry **next = list;
673 while (next < last) {
674 struct object_entry *obj = *next;
675 if (obj->sha1[0] != i)
676 break;
677 next++;
678 }
679 array[i] = htonl(next - sorted_by_sha);
680 list = next;
681 }
d1a46a9e 682 sha1write(f, array, 256 * 4);
9cf6d335 683
d1a46a9e 684 /* compute the SHA1 hash of sorted object names. */
84c8d8ae 685 SHA1_Init(&ctx);
d1a46a9e 686
9cf6d335
SV
687 /*
688 * Write the actual SHA1 entries..
689 */
690 list = sorted_by_sha;
691 for (i = 0; i < nr_objects; i++) {
692 struct object_entry *obj = *list++;
d1a46a9e
NP
693 if (index_version < 2) {
694 uint32_t offset = htonl(obj->offset);
695 sha1write(f, &offset, 4);
696 }
9cf6d335 697 sha1write(f, obj->sha1, 20);
84c8d8ae 698 SHA1_Update(&ctx, obj->sha1, 20);
9cf6d335 699 }
d1a46a9e
NP
700
701 if (index_version >= 2) {
702 unsigned int nr_large_offset = 0;
703
704 /* write the crc32 table */
705 list = sorted_by_sha;
706 for (i = 0; i < nr_objects; i++) {
707 struct object_entry *obj = *list++;
708 uint32_t crc32_val = htonl(obj->crc32);
709 sha1write(f, &crc32_val, 4);
710 }
711
712 /* write the 32-bit offset table */
713 list = sorted_by_sha;
714 for (i = 0; i < nr_objects; i++) {
715 struct object_entry *obj = *list++;
4ba7d711 716 uint32_t offset = (obj->offset <= index_off32_limit) ?
d1a46a9e
NP
717 obj->offset : (0x80000000 | nr_large_offset++);
718 offset = htonl(offset);
719 sha1write(f, &offset, 4);
720 }
721
722 /* write the large offset table */
723 list = sorted_by_sha;
724 while (nr_large_offset) {
725 struct object_entry *obj = *list++;
726 uint64_t offset = obj->offset;
4ba7d711 727 if (offset > index_off32_limit) {
d1a46a9e
NP
728 uint32_t split[2];
729 split[0] = htonl(offset >> 32);
730 split[1] = htonl(offset & 0xffffffff);
731 sha1write(f, split, 8);
732 nr_large_offset--;
733 }
734 }
735 }
736
2d477051 737 sha1write(f, sha1, 20);
9cf6d335
SV
738 sha1close(f, NULL, 1);
739 free(sorted_by_sha);
84c8d8ae 740 SHA1_Final(sha1, &ctx);
e42797f5
NP
741 return index_name;
742}
743
744static void final(const char *final_pack_name, const char *curr_pack_name,
745 const char *final_index_name, const char *curr_index_name,
b8077709 746 const char *keep_name, const char *keep_msg,
e42797f5
NP
747 unsigned char *sha1)
748{
3a55602e 749 const char *report = "pack";
e42797f5
NP
750 char name[PATH_MAX];
751 int err;
752
753 if (!from_stdin) {
754 close(input_fd);
755 } else {
756 err = close(output_fd);
757 if (err)
758 die("error while closing pack file: %s", strerror(errno));
759 chmod(curr_pack_name, 0444);
760 }
761
b8077709
SP
762 if (keep_msg) {
763 int keep_fd, keep_msg_len = strlen(keep_msg);
764 if (!keep_name) {
765 snprintf(name, sizeof(name), "%s/pack/pack-%s.keep",
766 get_object_directory(), sha1_to_hex(sha1));
767 keep_name = name;
768 }
9ca4a201
NP
769 keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
770 if (keep_fd < 0) {
771 if (errno != EEXIST)
772 die("cannot write keep file");
773 } else {
774 if (keep_msg_len > 0) {
775 write_or_die(keep_fd, keep_msg, keep_msg_len);
776 write_or_die(keep_fd, "\n", 1);
777 }
778 close(keep_fd);
576162a4 779 report = "keep";
b8077709 780 }
b8077709
SP
781 }
782
e42797f5
NP
783 if (final_pack_name != curr_pack_name) {
784 if (!final_pack_name) {
785 snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
786 get_object_directory(), sha1_to_hex(sha1));
787 final_pack_name = name;
788 }
789 if (move_temp_to_file(curr_pack_name, final_pack_name))
790 die("cannot store pack file");
791 }
792
793 chmod(curr_index_name, 0444);
794 if (final_index_name != curr_index_name) {
795 if (!final_index_name) {
796 snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
797 get_object_directory(), sha1_to_hex(sha1));
798 final_index_name = name;
799 }
800 if (move_temp_to_file(curr_index_name, final_index_name))
801 die("cannot store index file");
802 }
576162a4
NP
803
804 if (!from_stdin) {
805 printf("%s\n", sha1_to_hex(sha1));
806 } else {
807 char buf[48];
808 int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
809 report, sha1_to_hex(sha1));
d1b2ddc8 810 write_or_die(1, buf, len);
576162a4
NP
811
812 /*
813 * Let's just mimic git-unpack-objects here and write
814 * the last part of the input buffer to stdout.
815 */
816 while (input_len) {
817 err = xwrite(1, input_buffer + input_offset, input_len);
818 if (err <= 0)
819 break;
820 input_len -= err;
821 input_offset += err;
822 }
823 }
9cf6d335
SV
824}
825
826int main(int argc, char **argv)
827{
636171cb 828 int i, fix_thin_pack = 0;
e42797f5
NP
829 const char *curr_pack, *pack_name = NULL;
830 const char *curr_index, *index_name = NULL;
b8077709
SP
831 const char *keep_name = NULL, *keep_msg = NULL;
832 char *index_name_buf = NULL, *keep_name_buf = NULL;
84c8d8ae 833 unsigned char sha1[20];
9cf6d335
SV
834
835 for (i = 1; i < argc; i++) {
836 const char *arg = argv[i];
837
838 if (*arg == '-') {
e42797f5
NP
839 if (!strcmp(arg, "--stdin")) {
840 from_stdin = 1;
636171cb
NP
841 } else if (!strcmp(arg, "--fix-thin")) {
842 fix_thin_pack = 1;
b8077709
SP
843 } else if (!strcmp(arg, "--keep")) {
844 keep_msg = "";
cc44c765 845 } else if (!prefixcmp(arg, "--keep=")) {
b8077709 846 keep_msg = arg + 7;
cc44c765 847 } else if (!prefixcmp(arg, "--pack_header=")) {
bed006fb
NP
848 struct pack_header *hdr;
849 char *c;
850
851 hdr = (struct pack_header *)input_buffer;
852 hdr->hdr_signature = htonl(PACK_SIGNATURE);
853 hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
854 if (*c != ',')
855 die("bad %s", arg);
856 hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
857 if (*c)
858 die("bad %s", arg);
859 input_len = sizeof(*hdr);
3c9af366
NP
860 } else if (!strcmp(arg, "-v")) {
861 verbose = 1;
e42797f5 862 } else if (!strcmp(arg, "-o")) {
9cf6d335
SV
863 if (index_name || (i+1) >= argc)
864 usage(index_pack_usage);
865 index_name = argv[++i];
4ba7d711
NP
866 } else if (!prefixcmp(arg, "--index-version=")) {
867 char *c;
868 index_default_version = strtoul(arg + 16, &c, 10);
869 if (index_default_version > 2)
870 die("bad %s", arg);
871 if (*c == ',')
872 index_off32_limit = strtoul(c+1, &c, 0);
873 if (*c || index_off32_limit & 0x80000000)
874 die("bad %s", arg);
9cf6d335
SV
875 } else
876 usage(index_pack_usage);
877 continue;
878 }
879
880 if (pack_name)
881 usage(index_pack_usage);
882 pack_name = arg;
883 }
884
e42797f5 885 if (!pack_name && !from_stdin)
9cf6d335 886 usage(index_pack_usage);
636171cb
NP
887 if (fix_thin_pack && !from_stdin)
888 die("--fix-thin cannot be used without --stdin");
e42797f5 889 if (!index_name && pack_name) {
9cf6d335 890 int len = strlen(pack_name);
5bb1cda5 891 if (!has_extension(pack_name, ".pack"))
9cf6d335
SV
892 die("packfile name '%s' does not end with '.pack'",
893 pack_name);
6689f087 894 index_name_buf = xmalloc(len);
9cf6d335
SV
895 memcpy(index_name_buf, pack_name, len - 5);
896 strcpy(index_name_buf + len - 5, ".idx");
897 index_name = index_name_buf;
898 }
b8077709
SP
899 if (keep_msg && !keep_name && pack_name) {
900 int len = strlen(pack_name);
901 if (!has_extension(pack_name, ".pack"))
902 die("packfile name '%s' does not end with '.pack'",
903 pack_name);
904 keep_name_buf = xmalloc(len);
905 memcpy(keep_name_buf, pack_name, len - 5);
906 strcpy(keep_name_buf + len - 5, ".keep");
907 keep_name = keep_name_buf;
908 }
9cf6d335 909
e42797f5 910 curr_pack = open_pack_file(pack_name);
9cf6d335 911 parse_pack_header();
636171cb
NP
912 objects = xmalloc((nr_objects + 1) * sizeof(struct object_entry));
913 deltas = xmalloc(nr_objects * sizeof(struct delta_entry));
2d477051 914 parse_pack_objects(sha1);
96a02f8f
NP
915 if (nr_deltas == nr_resolved_deltas) {
916 if (verbose)
917 stop_progress(&progress);
918 /* Flush remaining pack final 20-byte SHA1. */
919 flush();
920 } else {
636171cb
NP
921 if (fix_thin_pack) {
922 int nr_unresolved = nr_deltas - nr_resolved_deltas;
3c9af366 923 int nr_objects_initial = nr_objects;
636171cb
NP
924 if (nr_unresolved <= 0)
925 die("confusion beyond insanity");
926 objects = xrealloc(objects,
927 (nr_objects + nr_unresolved + 1)
928 * sizeof(*objects));
929 fix_unresolved_deltas(nr_unresolved);
96a02f8f
NP
930 if (verbose) {
931 stop_progress(&progress);
3c9af366
NP
932 fprintf(stderr, "%d objects were added to complete this thin pack.\n",
933 nr_objects - nr_objects_initial);
96a02f8f 934 }
cbc6bdab
SP
935 fixup_pack_header_footer(output_fd, sha1,
936 curr_pack, nr_objects);
636171cb
NP
937 }
938 if (nr_deltas != nr_resolved_deltas)
939 die("pack has %d unresolved deltas",
940 nr_deltas - nr_resolved_deltas);
636171cb 941 }
9cf6d335 942 free(deltas);
e42797f5 943 curr_index = write_index_file(index_name, sha1);
b8077709
SP
944 final(pack_name, curr_pack,
945 index_name, curr_index,
946 keep_name, keep_msg,
947 sha1);
9cf6d335
SV
948 free(objects);
949 free(index_name_buf);
b8077709 950 free(keep_name_buf);
9cf6d335
SV
951
952 return 0;
953}