Merge branch 'jl/maint-fetch-recursive-fix' into maint
[git] / builtin / index-pack.c
1 #include "builtin.h"
2 #include "delta.h"
3 #include "pack.h"
4 #include "csum-file.h"
5 #include "blob.h"
6 #include "commit.h"
7 #include "tag.h"
8 #include "tree.h"
9 #include "progress.h"
10 #include "fsck.h"
11 #include "exec_cmd.h"
12
13 static const char index_pack_usage[] =
14 "git index-pack [-v] [-o <index-file>] [ --keep | --keep=<msg> ] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
15
16 struct object_entry {
17         struct pack_idx_entry idx;
18         unsigned long size;
19         unsigned int hdr_size;
20         enum object_type type;
21         enum object_type real_type;
22 };
23
24 union delta_base {
25         unsigned char sha1[20];
26         off_t offset;
27 };
28
29 struct base_data {
30         struct base_data *base;
31         struct base_data *child;
32         struct object_entry *obj;
33         void *data;
34         unsigned long size;
35 };
36
37 /*
38  * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
39  * to memcmp() only the first 20 bytes.
40  */
41 #define UNION_BASE_SZ   20
42
43 #define FLAG_LINK (1u<<20)
44 #define FLAG_CHECKED (1u<<21)
45
46 struct delta_entry {
47         union delta_base base;
48         int obj_no;
49 };
50
51 static struct object_entry *objects;
52 static struct delta_entry *deltas;
53 static struct base_data *base_cache;
54 static size_t base_cache_used;
55 static int nr_objects;
56 static int nr_deltas;
57 static int nr_resolved_deltas;
58
59 static int from_stdin;
60 static int strict;
61 static int verbose;
62
63 static struct progress *progress;
64
65 /* We always read in 4kB chunks. */
66 static unsigned char input_buffer[4096];
67 static unsigned int input_offset, input_len;
68 static off_t consumed_bytes;
69 static git_SHA_CTX input_ctx;
70 static uint32_t input_crc32;
71 static int input_fd, output_fd, pack_fd;
72
73 static int mark_link(struct object *obj, int type, void *data)
74 {
75         if (!obj)
76                 return -1;
77
78         if (type != OBJ_ANY && obj->type != type)
79                 die("object type mismatch at %s", sha1_to_hex(obj->sha1));
80
81         obj->flags |= FLAG_LINK;
82         return 0;
83 }
84
85 /* The content of each linked object must have been checked
86    or it must be already present in the object database */
87 static void check_object(struct object *obj)
88 {
89         if (!obj)
90                 return;
91
92         if (!(obj->flags & FLAG_LINK))
93                 return;
94
95         if (!(obj->flags & FLAG_CHECKED)) {
96                 unsigned long size;
97                 int type = sha1_object_info(obj->sha1, &size);
98                 if (type != obj->type || type <= 0)
99                         die("object of unexpected type");
100                 obj->flags |= FLAG_CHECKED;
101                 return;
102         }
103 }
104
105 static void check_objects(void)
106 {
107         unsigned i, max;
108
109         max = get_max_object_index();
110         for (i = 0; i < max; i++)
111                 check_object(get_indexed_object(i));
112 }
113
114
115 /* Discard current buffer used content. */
116 static void flush(void)
117 {
118         if (input_offset) {
119                 if (output_fd >= 0)
120                         write_or_die(output_fd, input_buffer, input_offset);
121                 git_SHA1_Update(&input_ctx, input_buffer, input_offset);
122                 memmove(input_buffer, input_buffer + input_offset, input_len);
123                 input_offset = 0;
124         }
125 }
126
127 /*
128  * Make sure at least "min" bytes are available in the buffer, and
129  * return the pointer to the buffer.
130  */
131 static void *fill(int min)
132 {
133         if (min <= input_len)
134                 return input_buffer + input_offset;
135         if (min > sizeof(input_buffer))
136                 die("cannot fill %d bytes", min);
137         flush();
138         do {
139                 ssize_t ret = xread(input_fd, input_buffer + input_len,
140                                 sizeof(input_buffer) - input_len);
141                 if (ret <= 0) {
142                         if (!ret)
143                                 die("early EOF");
144                         die_errno("read error on input");
145                 }
146                 input_len += ret;
147                 if (from_stdin)
148                         display_throughput(progress, consumed_bytes + input_len);
149         } while (input_len < min);
150         return input_buffer;
151 }
152
153 static void use(int bytes)
154 {
155         if (bytes > input_len)
156                 die("used more bytes than were available");
157         input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
158         input_len -= bytes;
159         input_offset += bytes;
160
161         /* make sure off_t is sufficiently large not to wrap */
162         if (signed_add_overflows(consumed_bytes, bytes))
163                 die("pack too large for current definition of off_t");
164         consumed_bytes += bytes;
165 }
166
167 static const char *open_pack_file(const char *pack_name)
168 {
169         if (from_stdin) {
170                 input_fd = 0;
171                 if (!pack_name) {
172                         static char tmpfile[PATH_MAX];
173                         output_fd = odb_mkstemp(tmpfile, sizeof(tmpfile),
174                                                 "pack/tmp_pack_XXXXXX");
175                         pack_name = xstrdup(tmpfile);
176                 } else
177                         output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
178                 if (output_fd < 0)
179                         die_errno("unable to create '%s'", pack_name);
180                 pack_fd = output_fd;
181         } else {
182                 input_fd = open(pack_name, O_RDONLY);
183                 if (input_fd < 0)
184                         die_errno("cannot open packfile '%s'", pack_name);
185                 output_fd = -1;
186                 pack_fd = input_fd;
187         }
188         git_SHA1_Init(&input_ctx);
189         return pack_name;
190 }
191
192 static void parse_pack_header(void)
193 {
194         struct pack_header *hdr = fill(sizeof(struct pack_header));
195
196         /* Header consistency check */
197         if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
198                 die("pack signature mismatch");
199         if (!pack_version_ok(hdr->hdr_version))
200                 die("pack version %"PRIu32" unsupported",
201                         ntohl(hdr->hdr_version));
202
203         nr_objects = ntohl(hdr->hdr_entries);
204         use(sizeof(struct pack_header));
205 }
206
207 static NORETURN void bad_object(unsigned long offset, const char *format,
208                        ...) __attribute__((format (printf, 2, 3)));
209
210 static NORETURN void bad_object(unsigned long offset, const char *format, ...)
211 {
212         va_list params;
213         char buf[1024];
214
215         va_start(params, format);
216         vsnprintf(buf, sizeof(buf), format, params);
217         va_end(params);
218         die("pack has bad object at offset %lu: %s", offset, buf);
219 }
220
221 static void free_base_data(struct base_data *c)
222 {
223         if (c->data) {
224                 free(c->data);
225                 c->data = NULL;
226                 base_cache_used -= c->size;
227         }
228 }
229
230 static void prune_base_data(struct base_data *retain)
231 {
232         struct base_data *b;
233         for (b = base_cache;
234              base_cache_used > delta_base_cache_limit && b;
235              b = b->child) {
236                 if (b->data && b != retain)
237                         free_base_data(b);
238         }
239 }
240
241 static void link_base_data(struct base_data *base, struct base_data *c)
242 {
243         if (base)
244                 base->child = c;
245         else
246                 base_cache = c;
247
248         c->base = base;
249         c->child = NULL;
250         if (c->data)
251                 base_cache_used += c->size;
252         prune_base_data(c);
253 }
254
255 static void unlink_base_data(struct base_data *c)
256 {
257         struct base_data *base = c->base;
258         if (base)
259                 base->child = NULL;
260         else
261                 base_cache = NULL;
262         free_base_data(c);
263 }
264
265 static void *unpack_entry_data(unsigned long offset, unsigned long size)
266 {
267         int status;
268         z_stream stream;
269         void *buf = xmalloc(size);
270
271         memset(&stream, 0, sizeof(stream));
272         git_inflate_init(&stream);
273         stream.next_out = buf;
274         stream.avail_out = size;
275
276         do {
277                 stream.next_in = fill(1);
278                 stream.avail_in = input_len;
279                 status = git_inflate(&stream, 0);
280                 use(input_len - stream.avail_in);
281         } while (status == Z_OK);
282         if (stream.total_out != size || status != Z_STREAM_END)
283                 bad_object(offset, "inflate returned %d", status);
284         git_inflate_end(&stream);
285         return buf;
286 }
287
288 static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_base)
289 {
290         unsigned char *p;
291         unsigned long size, c;
292         off_t base_offset;
293         unsigned shift;
294         void *data;
295
296         obj->idx.offset = consumed_bytes;
297         input_crc32 = crc32(0, NULL, 0);
298
299         p = fill(1);
300         c = *p;
301         use(1);
302         obj->type = (c >> 4) & 7;
303         size = (c & 15);
304         shift = 4;
305         while (c & 0x80) {
306                 p = fill(1);
307                 c = *p;
308                 use(1);
309                 size += (c & 0x7f) << shift;
310                 shift += 7;
311         }
312         obj->size = size;
313
314         switch (obj->type) {
315         case OBJ_REF_DELTA:
316                 hashcpy(delta_base->sha1, fill(20));
317                 use(20);
318                 break;
319         case OBJ_OFS_DELTA:
320                 memset(delta_base, 0, sizeof(*delta_base));
321                 p = fill(1);
322                 c = *p;
323                 use(1);
324                 base_offset = c & 127;
325                 while (c & 128) {
326                         base_offset += 1;
327                         if (!base_offset || MSB(base_offset, 7))
328                                 bad_object(obj->idx.offset, "offset value overflow for delta base object");
329                         p = fill(1);
330                         c = *p;
331                         use(1);
332                         base_offset = (base_offset << 7) + (c & 127);
333                 }
334                 delta_base->offset = obj->idx.offset - base_offset;
335                 if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
336                         bad_object(obj->idx.offset, "delta base offset is out of bound");
337                 break;
338         case OBJ_COMMIT:
339         case OBJ_TREE:
340         case OBJ_BLOB:
341         case OBJ_TAG:
342                 break;
343         default:
344                 bad_object(obj->idx.offset, "unknown object type %d", obj->type);
345         }
346         obj->hdr_size = consumed_bytes - obj->idx.offset;
347
348         data = unpack_entry_data(obj->idx.offset, obj->size);
349         obj->idx.crc32 = input_crc32;
350         return data;
351 }
352
353 static void *get_data_from_pack(struct object_entry *obj)
354 {
355         off_t from = obj[0].idx.offset + obj[0].hdr_size;
356         unsigned long len = obj[1].idx.offset - from;
357         unsigned char *data, *inbuf;
358         z_stream stream;
359         int status;
360
361         data = xmalloc(obj->size);
362         inbuf = xmalloc((len < 64*1024) ? len : 64*1024);
363
364         memset(&stream, 0, sizeof(stream));
365         git_inflate_init(&stream);
366         stream.next_out = data;
367         stream.avail_out = obj->size;
368
369         do {
370                 ssize_t n = (len < 64*1024) ? len : 64*1024;
371                 n = pread(pack_fd, inbuf, n, from);
372                 if (n < 0)
373                         die_errno("cannot pread pack file");
374                 if (!n)
375                         die("premature end of pack file, %lu bytes missing", len);
376                 from += n;
377                 len -= n;
378                 stream.next_in = inbuf;
379                 stream.avail_in = n;
380                 status = git_inflate(&stream, 0);
381         } while (len && status == Z_OK && !stream.avail_in);
382
383         /* This has been inflated OK when first encountered, so... */
384         if (status != Z_STREAM_END || stream.total_out != obj->size)
385                 die("serious inflate inconsistency");
386
387         git_inflate_end(&stream);
388         free(inbuf);
389         return data;
390 }
391
392 static int find_delta(const union delta_base *base)
393 {
394         int first = 0, last = nr_deltas;
395
396         while (first < last) {
397                 int next = (first + last) / 2;
398                 struct delta_entry *delta = &deltas[next];
399                 int cmp;
400
401                 cmp = memcmp(base, &delta->base, UNION_BASE_SZ);
402                 if (!cmp)
403                         return next;
404                 if (cmp < 0) {
405                         last = next;
406                         continue;
407                 }
408                 first = next+1;
409         }
410         return -first-1;
411 }
412
413 static void find_delta_children(const union delta_base *base,
414                                 int *first_index, int *last_index)
415 {
416         int first = find_delta(base);
417         int last = first;
418         int end = nr_deltas - 1;
419
420         if (first < 0) {
421                 *first_index = 0;
422                 *last_index = -1;
423                 return;
424         }
425         while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
426                 --first;
427         while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
428                 ++last;
429         *first_index = first;
430         *last_index = last;
431 }
432
433 static void sha1_object(const void *data, unsigned long size,
434                         enum object_type type, unsigned char *sha1)
435 {
436         hash_sha1_file(data, size, typename(type), sha1);
437         if (has_sha1_file(sha1)) {
438                 void *has_data;
439                 enum object_type has_type;
440                 unsigned long has_size;
441                 has_data = read_sha1_file(sha1, &has_type, &has_size);
442                 if (!has_data)
443                         die("cannot read existing object %s", sha1_to_hex(sha1));
444                 if (size != has_size || type != has_type ||
445                     memcmp(data, has_data, size) != 0)
446                         die("SHA1 COLLISION FOUND WITH %s !", sha1_to_hex(sha1));
447                 free(has_data);
448         }
449         if (strict) {
450                 if (type == OBJ_BLOB) {
451                         struct blob *blob = lookup_blob(sha1);
452                         if (blob)
453                                 blob->object.flags |= FLAG_CHECKED;
454                         else
455                                 die("invalid blob object %s", sha1_to_hex(sha1));
456                 } else {
457                         struct object *obj;
458                         int eaten;
459                         void *buf = (void *) data;
460
461                         /*
462                          * we do not need to free the memory here, as the
463                          * buf is deleted by the caller.
464                          */
465                         obj = parse_object_buffer(sha1, type, size, buf, &eaten);
466                         if (!obj)
467                                 die("invalid %s", typename(type));
468                         if (fsck_object(obj, 1, fsck_error_function))
469                                 die("Error in object");
470                         if (fsck_walk(obj, mark_link, NULL))
471                                 die("Not all child objects of %s are reachable", sha1_to_hex(obj->sha1));
472
473                         if (obj->type == OBJ_TREE) {
474                                 struct tree *item = (struct tree *) obj;
475                                 item->buffer = NULL;
476                         }
477                         if (obj->type == OBJ_COMMIT) {
478                                 struct commit *commit = (struct commit *) obj;
479                                 commit->buffer = NULL;
480                         }
481                         obj->flags |= FLAG_CHECKED;
482                 }
483         }
484 }
485
486 static void *get_base_data(struct base_data *c)
487 {
488         if (!c->data) {
489                 struct object_entry *obj = c->obj;
490
491                 if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
492                         void *base = get_base_data(c->base);
493                         void *raw = get_data_from_pack(obj);
494                         c->data = patch_delta(
495                                 base, c->base->size,
496                                 raw, obj->size,
497                                 &c->size);
498                         free(raw);
499                         if (!c->data)
500                                 bad_object(obj->idx.offset, "failed to apply delta");
501                 } else {
502                         c->data = get_data_from_pack(obj);
503                         c->size = obj->size;
504                 }
505
506                 base_cache_used += c->size;
507                 prune_base_data(c);
508         }
509         return c->data;
510 }
511
512 static void resolve_delta(struct object_entry *delta_obj,
513                           struct base_data *base, struct base_data *result)
514 {
515         void *base_data, *delta_data;
516
517         delta_obj->real_type = base->obj->real_type;
518         delta_data = get_data_from_pack(delta_obj);
519         base_data = get_base_data(base);
520         result->obj = delta_obj;
521         result->data = patch_delta(base_data, base->size,
522                                    delta_data, delta_obj->size, &result->size);
523         free(delta_data);
524         if (!result->data)
525                 bad_object(delta_obj->idx.offset, "failed to apply delta");
526         sha1_object(result->data, result->size, delta_obj->real_type,
527                     delta_obj->idx.sha1);
528         nr_resolved_deltas++;
529 }
530
531 static void find_unresolved_deltas(struct base_data *base,
532                                    struct base_data *prev_base)
533 {
534         int i, ref_first, ref_last, ofs_first, ofs_last;
535
536         /*
537          * This is a recursive function. Those brackets should help reducing
538          * stack usage by limiting the scope of the delta_base union.
539          */
540         {
541                 union delta_base base_spec;
542
543                 hashcpy(base_spec.sha1, base->obj->idx.sha1);
544                 find_delta_children(&base_spec, &ref_first, &ref_last);
545
546                 memset(&base_spec, 0, sizeof(base_spec));
547                 base_spec.offset = base->obj->idx.offset;
548                 find_delta_children(&base_spec, &ofs_first, &ofs_last);
549         }
550
551         if (ref_last == -1 && ofs_last == -1) {
552                 free(base->data);
553                 return;
554         }
555
556         link_base_data(prev_base, base);
557
558         for (i = ref_first; i <= ref_last; i++) {
559                 struct object_entry *child = objects + deltas[i].obj_no;
560                 if (child->real_type == OBJ_REF_DELTA) {
561                         struct base_data result;
562                         resolve_delta(child, base, &result);
563                         if (i == ref_last && ofs_last == -1)
564                                 free_base_data(base);
565                         find_unresolved_deltas(&result, base);
566                 }
567         }
568
569         for (i = ofs_first; i <= ofs_last; i++) {
570                 struct object_entry *child = objects + deltas[i].obj_no;
571                 if (child->real_type == OBJ_OFS_DELTA) {
572                         struct base_data result;
573                         resolve_delta(child, base, &result);
574                         if (i == ofs_last)
575                                 free_base_data(base);
576                         find_unresolved_deltas(&result, base);
577                 }
578         }
579
580         unlink_base_data(base);
581 }
582
583 static int compare_delta_entry(const void *a, const void *b)
584 {
585         const struct delta_entry *delta_a = a;
586         const struct delta_entry *delta_b = b;
587         return memcmp(&delta_a->base, &delta_b->base, UNION_BASE_SZ);
588 }
589
590 /* Parse all objects and return the pack content SHA1 hash */
591 static void parse_pack_objects(unsigned char *sha1)
592 {
593         int i;
594         struct delta_entry *delta = deltas;
595         struct stat st;
596
597         /*
598          * First pass:
599          * - find locations of all objects;
600          * - calculate SHA1 of all non-delta objects;
601          * - remember base (SHA1 or offset) for all deltas.
602          */
603         if (verbose)
604                 progress = start_progress(
605                                 from_stdin ? "Receiving objects" : "Indexing objects",
606                                 nr_objects);
607         for (i = 0; i < nr_objects; i++) {
608                 struct object_entry *obj = &objects[i];
609                 void *data = unpack_raw_entry(obj, &delta->base);
610                 obj->real_type = obj->type;
611                 if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
612                         nr_deltas++;
613                         delta->obj_no = i;
614                         delta++;
615                 } else
616                         sha1_object(data, obj->size, obj->type, obj->idx.sha1);
617                 free(data);
618                 display_progress(progress, i+1);
619         }
620         objects[i].idx.offset = consumed_bytes;
621         stop_progress(&progress);
622
623         /* Check pack integrity */
624         flush();
625         git_SHA1_Final(sha1, &input_ctx);
626         if (hashcmp(fill(20), sha1))
627                 die("pack is corrupted (SHA1 mismatch)");
628         use(20);
629
630         /* If input_fd is a file, we should have reached its end now. */
631         if (fstat(input_fd, &st))
632                 die_errno("cannot fstat packfile");
633         if (S_ISREG(st.st_mode) &&
634                         lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
635                 die("pack has junk at the end");
636
637         if (!nr_deltas)
638                 return;
639
640         /* Sort deltas by base SHA1/offset for fast searching */
641         qsort(deltas, nr_deltas, sizeof(struct delta_entry),
642               compare_delta_entry);
643
644         /*
645          * Second pass:
646          * - for all non-delta objects, look if it is used as a base for
647          *   deltas;
648          * - if used as a base, uncompress the object and apply all deltas,
649          *   recursively checking if the resulting object is used as a base
650          *   for some more deltas.
651          */
652         if (verbose)
653                 progress = start_progress("Resolving deltas", nr_deltas);
654         for (i = 0; i < nr_objects; i++) {
655                 struct object_entry *obj = &objects[i];
656                 struct base_data base_obj;
657
658                 if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA)
659                         continue;
660                 base_obj.obj = obj;
661                 base_obj.data = NULL;
662                 find_unresolved_deltas(&base_obj, NULL);
663                 display_progress(progress, nr_resolved_deltas);
664         }
665 }
666
667 static int write_compressed(struct sha1file *f, void *in, unsigned int size)
668 {
669         z_stream stream;
670         int status;
671         unsigned char outbuf[4096];
672
673         memset(&stream, 0, sizeof(stream));
674         deflateInit(&stream, zlib_compression_level);
675         stream.next_in = in;
676         stream.avail_in = size;
677
678         do {
679                 stream.next_out = outbuf;
680                 stream.avail_out = sizeof(outbuf);
681                 status = deflate(&stream, Z_FINISH);
682                 sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
683         } while (status == Z_OK);
684
685         if (status != Z_STREAM_END)
686                 die("unable to deflate appended object (%d)", status);
687         size = stream.total_out;
688         deflateEnd(&stream);
689         return size;
690 }
691
692 static struct object_entry *append_obj_to_pack(struct sha1file *f,
693                                const unsigned char *sha1, void *buf,
694                                unsigned long size, enum object_type type)
695 {
696         struct object_entry *obj = &objects[nr_objects++];
697         unsigned char header[10];
698         unsigned long s = size;
699         int n = 0;
700         unsigned char c = (type << 4) | (s & 15);
701         s >>= 4;
702         while (s) {
703                 header[n++] = c | 0x80;
704                 c = s & 0x7f;
705                 s >>= 7;
706         }
707         header[n++] = c;
708         crc32_begin(f);
709         sha1write(f, header, n);
710         obj[0].size = size;
711         obj[0].hdr_size = n;
712         obj[0].type = type;
713         obj[0].real_type = type;
714         obj[1].idx.offset = obj[0].idx.offset + n;
715         obj[1].idx.offset += write_compressed(f, buf, size);
716         obj[0].idx.crc32 = crc32_end(f);
717         sha1flush(f);
718         hashcpy(obj->idx.sha1, sha1);
719         return obj;
720 }
721
722 static int delta_pos_compare(const void *_a, const void *_b)
723 {
724         struct delta_entry *a = *(struct delta_entry **)_a;
725         struct delta_entry *b = *(struct delta_entry **)_b;
726         return a->obj_no - b->obj_no;
727 }
728
729 static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved)
730 {
731         struct delta_entry **sorted_by_pos;
732         int i, n = 0;
733
734         /*
735          * Since many unresolved deltas may well be themselves base objects
736          * for more unresolved deltas, we really want to include the
737          * smallest number of base objects that would cover as much delta
738          * as possible by picking the
739          * trunc deltas first, allowing for other deltas to resolve without
740          * additional base objects.  Since most base objects are to be found
741          * before deltas depending on them, a good heuristic is to start
742          * resolving deltas in the same order as their position in the pack.
743          */
744         sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
745         for (i = 0; i < nr_deltas; i++) {
746                 if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
747                         continue;
748                 sorted_by_pos[n++] = &deltas[i];
749         }
750         qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
751
752         for (i = 0; i < n; i++) {
753                 struct delta_entry *d = sorted_by_pos[i];
754                 enum object_type type;
755                 struct base_data base_obj;
756
757                 if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
758                         continue;
759                 base_obj.data = read_sha1_file(d->base.sha1, &type, &base_obj.size);
760                 if (!base_obj.data)
761                         continue;
762
763                 if (check_sha1_signature(d->base.sha1, base_obj.data,
764                                 base_obj.size, typename(type)))
765                         die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
766                 base_obj.obj = append_obj_to_pack(f, d->base.sha1,
767                                         base_obj.data, base_obj.size, type);
768                 find_unresolved_deltas(&base_obj, NULL);
769                 display_progress(progress, nr_resolved_deltas);
770         }
771         free(sorted_by_pos);
772 }
773
774 static void final(const char *final_pack_name, const char *curr_pack_name,
775                   const char *final_index_name, const char *curr_index_name,
776                   const char *keep_name, const char *keep_msg,
777                   unsigned char *sha1)
778 {
779         const char *report = "pack";
780         char name[PATH_MAX];
781         int err;
782
783         if (!from_stdin) {
784                 close(input_fd);
785         } else {
786                 fsync_or_die(output_fd, curr_pack_name);
787                 err = close(output_fd);
788                 if (err)
789                         die_errno("error while closing pack file");
790         }
791
792         if (keep_msg) {
793                 int keep_fd, keep_msg_len = strlen(keep_msg);
794
795                 if (!keep_name)
796                         keep_fd = odb_pack_keep(name, sizeof(name), sha1);
797                 else
798                         keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
799
800                 if (keep_fd < 0) {
801                         if (errno != EEXIST)
802                                 die_errno("cannot write keep file '%s'",
803                                           keep_name);
804                 } else {
805                         if (keep_msg_len > 0) {
806                                 write_or_die(keep_fd, keep_msg, keep_msg_len);
807                                 write_or_die(keep_fd, "\n", 1);
808                         }
809                         if (close(keep_fd) != 0)
810                                 die_errno("cannot close written keep file '%s'",
811                                     keep_name);
812                         report = "keep";
813                 }
814         }
815
816         if (final_pack_name != curr_pack_name) {
817                 if (!final_pack_name) {
818                         snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
819                                  get_object_directory(), sha1_to_hex(sha1));
820                         final_pack_name = name;
821                 }
822                 if (move_temp_to_file(curr_pack_name, final_pack_name))
823                         die("cannot store pack file");
824         } else if (from_stdin)
825                 chmod(final_pack_name, 0444);
826
827         if (final_index_name != curr_index_name) {
828                 if (!final_index_name) {
829                         snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
830                                  get_object_directory(), sha1_to_hex(sha1));
831                         final_index_name = name;
832                 }
833                 if (move_temp_to_file(curr_index_name, final_index_name))
834                         die("cannot store index file");
835         } else
836                 chmod(final_index_name, 0444);
837
838         if (!from_stdin) {
839                 printf("%s\n", sha1_to_hex(sha1));
840         } else {
841                 char buf[48];
842                 int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
843                                    report, sha1_to_hex(sha1));
844                 write_or_die(1, buf, len);
845
846                 /*
847                  * Let's just mimic git-unpack-objects here and write
848                  * the last part of the input buffer to stdout.
849                  */
850                 while (input_len) {
851                         err = xwrite(1, input_buffer + input_offset, input_len);
852                         if (err <= 0)
853                                 break;
854                         input_len -= err;
855                         input_offset += err;
856                 }
857         }
858 }
859
860 static int git_index_pack_config(const char *k, const char *v, void *cb)
861 {
862         if (!strcmp(k, "pack.indexversion")) {
863                 pack_idx_default_version = git_config_int(k, v);
864                 if (pack_idx_default_version > 2)
865                         die("bad pack.indexversion=%"PRIu32,
866                                 pack_idx_default_version);
867                 return 0;
868         }
869         return git_default_config(k, v, cb);
870 }
871
872 int cmd_index_pack(int argc, const char **argv, const char *prefix)
873 {
874         int i, fix_thin_pack = 0;
875         const char *curr_pack, *curr_index;
876         const char *index_name = NULL, *pack_name = NULL;
877         const char *keep_name = NULL, *keep_msg = NULL;
878         char *index_name_buf = NULL, *keep_name_buf = NULL;
879         struct pack_idx_entry **idx_objects;
880         unsigned char pack_sha1[20];
881
882         if (argc == 2 && !strcmp(argv[1], "-h"))
883                 usage(index_pack_usage);
884
885         read_replace_refs = 0;
886
887         git_config(git_index_pack_config, NULL);
888         if (prefix && chdir(prefix))
889                 die("Cannot come back to cwd");
890
891         for (i = 1; i < argc; i++) {
892                 const char *arg = argv[i];
893
894                 if (*arg == '-') {
895                         if (!strcmp(arg, "--stdin")) {
896                                 from_stdin = 1;
897                         } else if (!strcmp(arg, "--fix-thin")) {
898                                 fix_thin_pack = 1;
899                         } else if (!strcmp(arg, "--strict")) {
900                                 strict = 1;
901                         } else if (!strcmp(arg, "--keep")) {
902                                 keep_msg = "";
903                         } else if (!prefixcmp(arg, "--keep=")) {
904                                 keep_msg = arg + 7;
905                         } else if (!prefixcmp(arg, "--pack_header=")) {
906                                 struct pack_header *hdr;
907                                 char *c;
908
909                                 hdr = (struct pack_header *)input_buffer;
910                                 hdr->hdr_signature = htonl(PACK_SIGNATURE);
911                                 hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
912                                 if (*c != ',')
913                                         die("bad %s", arg);
914                                 hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
915                                 if (*c)
916                                         die("bad %s", arg);
917                                 input_len = sizeof(*hdr);
918                         } else if (!strcmp(arg, "-v")) {
919                                 verbose = 1;
920                         } else if (!strcmp(arg, "-o")) {
921                                 if (index_name || (i+1) >= argc)
922                                         usage(index_pack_usage);
923                                 index_name = argv[++i];
924                         } else if (!prefixcmp(arg, "--index-version=")) {
925                                 char *c;
926                                 pack_idx_default_version = strtoul(arg + 16, &c, 10);
927                                 if (pack_idx_default_version > 2)
928                                         die("bad %s", arg);
929                                 if (*c == ',')
930                                         pack_idx_off32_limit = strtoul(c+1, &c, 0);
931                                 if (*c || pack_idx_off32_limit & 0x80000000)
932                                         die("bad %s", arg);
933                         } else
934                                 usage(index_pack_usage);
935                         continue;
936                 }
937
938                 if (pack_name)
939                         usage(index_pack_usage);
940                 pack_name = arg;
941         }
942
943         if (!pack_name && !from_stdin)
944                 usage(index_pack_usage);
945         if (fix_thin_pack && !from_stdin)
946                 die("--fix-thin cannot be used without --stdin");
947         if (!index_name && pack_name) {
948                 int len = strlen(pack_name);
949                 if (!has_extension(pack_name, ".pack"))
950                         die("packfile name '%s' does not end with '.pack'",
951                             pack_name);
952                 index_name_buf = xmalloc(len);
953                 memcpy(index_name_buf, pack_name, len - 5);
954                 strcpy(index_name_buf + len - 5, ".idx");
955                 index_name = index_name_buf;
956         }
957         if (keep_msg && !keep_name && pack_name) {
958                 int len = strlen(pack_name);
959                 if (!has_extension(pack_name, ".pack"))
960                         die("packfile name '%s' does not end with '.pack'",
961                             pack_name);
962                 keep_name_buf = xmalloc(len);
963                 memcpy(keep_name_buf, pack_name, len - 5);
964                 strcpy(keep_name_buf + len - 5, ".keep");
965                 keep_name = keep_name_buf;
966         }
967
968         curr_pack = open_pack_file(pack_name);
969         parse_pack_header();
970         objects = xmalloc((nr_objects + 1) * sizeof(struct object_entry));
971         deltas = xmalloc(nr_objects * sizeof(struct delta_entry));
972         parse_pack_objects(pack_sha1);
973         if (nr_deltas == nr_resolved_deltas) {
974                 stop_progress(&progress);
975                 /* Flush remaining pack final 20-byte SHA1. */
976                 flush();
977         } else {
978                 if (fix_thin_pack) {
979                         struct sha1file *f;
980                         unsigned char read_sha1[20], tail_sha1[20];
981                         char msg[48];
982                         int nr_unresolved = nr_deltas - nr_resolved_deltas;
983                         int nr_objects_initial = nr_objects;
984                         if (nr_unresolved <= 0)
985                                 die("confusion beyond insanity");
986                         objects = xrealloc(objects,
987                                            (nr_objects + nr_unresolved + 1)
988                                            * sizeof(*objects));
989                         f = sha1fd(output_fd, curr_pack);
990                         fix_unresolved_deltas(f, nr_unresolved);
991                         sprintf(msg, "completed with %d local objects",
992                                 nr_objects - nr_objects_initial);
993                         stop_progress_msg(&progress, msg);
994                         sha1close(f, tail_sha1, 0);
995                         hashcpy(read_sha1, pack_sha1);
996                         fixup_pack_header_footer(output_fd, pack_sha1,
997                                                  curr_pack, nr_objects,
998                                                  read_sha1, consumed_bytes-20);
999                         if (hashcmp(read_sha1, tail_sha1) != 0)
1000                                 die("Unexpected tail checksum for %s "
1001                                     "(disk corruption?)", curr_pack);
1002                 }
1003                 if (nr_deltas != nr_resolved_deltas)
1004                         die("pack has %d unresolved deltas",
1005                             nr_deltas - nr_resolved_deltas);
1006         }
1007         free(deltas);
1008         if (strict)
1009                 check_objects();
1010
1011         idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
1012         for (i = 0; i < nr_objects; i++)
1013                 idx_objects[i] = &objects[i].idx;
1014         curr_index = write_idx_file(index_name, idx_objects, nr_objects, pack_sha1);
1015         free(idx_objects);
1016
1017         final(pack_name, curr_pack,
1018                 index_name, curr_index,
1019                 keep_name, keep_msg,
1020                 pack_sha1);
1021         free(objects);
1022         free(index_name_buf);
1023         free(keep_name_buf);
1024         if (pack_name == NULL)
1025                 free((void *) curr_pack);
1026         if (index_name == NULL)
1027                 free((void *) curr_index);
1028
1029         return 0;
1030 }