Fix breakage in git-rev-list.txt
[git] / index-pack.c
1 #include "cache.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
11 static const char index_pack_usage[] =
12 "git-index-pack [-v] [-o <index-file>] [{ ---keep | --keep=<msg> }] { <pack-file> | --stdin [--fix-thin] [<pack-file>] }";
13
14 struct object_entry
15 {
16         struct pack_idx_entry idx;
17         unsigned long size;
18         unsigned int hdr_size;
19         enum object_type type;
20         enum object_type real_type;
21 };
22
23 union delta_base {
24         unsigned char sha1[20];
25         off_t offset;
26 };
27
28 /*
29  * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
30  * to memcmp() only the first 20 bytes.
31  */
32 #define UNION_BASE_SZ   20
33
34 struct delta_entry
35 {
36         union delta_base base;
37         int obj_no;
38 };
39
40 static struct object_entry *objects;
41 static struct delta_entry *deltas;
42 static int nr_objects;
43 static int nr_deltas;
44 static int nr_resolved_deltas;
45
46 static int from_stdin;
47 static int verbose;
48
49 static struct progress progress;
50
51 /* We always read in 4kB chunks. */
52 static unsigned char input_buffer[4096];
53 static unsigned int input_offset, input_len;
54 static off_t consumed_bytes;
55 static SHA_CTX input_ctx;
56 static uint32_t input_crc32;
57 static int input_fd, output_fd, pack_fd;
58
59 /* Discard current buffer used content. */
60 static void flush(void)
61 {
62         if (input_offset) {
63                 if (output_fd >= 0)
64                         write_or_die(output_fd, input_buffer, input_offset);
65                 SHA1_Update(&input_ctx, input_buffer, input_offset);
66                 memmove(input_buffer, input_buffer + input_offset, input_len);
67                 input_offset = 0;
68         }
69 }
70
71 /*
72  * Make sure at least "min" bytes are available in the buffer, and
73  * return the pointer to the buffer.
74  */
75 static void *fill(int min)
76 {
77         if (min <= input_len)
78                 return input_buffer + input_offset;
79         if (min > sizeof(input_buffer))
80                 die("cannot fill %d bytes", min);
81         flush();
82         do {
83                 ssize_t ret = xread(input_fd, input_buffer + input_len,
84                                 sizeof(input_buffer) - input_len);
85                 if (ret <= 0) {
86                         if (!ret)
87                                 die("early EOF");
88                         die("read error on input: %s", strerror(errno));
89                 }
90                 input_len += ret;
91         } while (input_len < min);
92         return input_buffer;
93 }
94
95 static void use(int bytes)
96 {
97         if (bytes > input_len)
98                 die("used more bytes than were available");
99         input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
100         input_len -= bytes;
101         input_offset += bytes;
102
103         /* make sure off_t is sufficiently large not to wrap */
104         if (consumed_bytes > consumed_bytes + bytes)
105                 die("pack too large for current definition of off_t");
106         consumed_bytes += bytes;
107 }
108
109 static const char *open_pack_file(const char *pack_name)
110 {
111         if (from_stdin) {
112                 input_fd = 0;
113                 if (!pack_name) {
114                         static char tmpfile[PATH_MAX];
115                         snprintf(tmpfile, sizeof(tmpfile),
116                                  "%s/tmp_pack_XXXXXX", get_object_directory());
117                         output_fd = xmkstemp(tmpfile);
118                         pack_name = xstrdup(tmpfile);
119                 } else
120                         output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
121                 if (output_fd < 0)
122                         die("unable to create %s: %s\n", pack_name, strerror(errno));
123                 pack_fd = output_fd;
124         } else {
125                 input_fd = open(pack_name, O_RDONLY);
126                 if (input_fd < 0)
127                         die("cannot open packfile '%s': %s",
128                             pack_name, strerror(errno));
129                 output_fd = -1;
130                 pack_fd = input_fd;
131         }
132         SHA1_Init(&input_ctx);
133         return pack_name;
134 }
135
136 static void parse_pack_header(void)
137 {
138         struct pack_header *hdr = fill(sizeof(struct pack_header));
139
140         /* Header consistency check */
141         if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
142                 die("pack signature mismatch");
143         if (!pack_version_ok(hdr->hdr_version))
144                 die("pack version %d unsupported", ntohl(hdr->hdr_version));
145
146         nr_objects = ntohl(hdr->hdr_entries);
147         use(sizeof(struct pack_header));
148 }
149
150 static void bad_object(unsigned long offset, const char *format,
151                        ...) NORETURN __attribute__((format (printf, 2, 3)));
152
153 static void bad_object(unsigned long offset, const char *format, ...)
154 {
155         va_list params;
156         char buf[1024];
157
158         va_start(params, format);
159         vsnprintf(buf, sizeof(buf), format, params);
160         va_end(params);
161         die("pack has bad object at offset %lu: %s", offset, buf);
162 }
163
164 static void *unpack_entry_data(unsigned long offset, unsigned long size)
165 {
166         z_stream stream;
167         void *buf = xmalloc(size);
168
169         memset(&stream, 0, sizeof(stream));
170         stream.next_out = buf;
171         stream.avail_out = size;
172         stream.next_in = fill(1);
173         stream.avail_in = input_len;
174         inflateInit(&stream);
175
176         for (;;) {
177                 int ret = inflate(&stream, 0);
178                 use(input_len - stream.avail_in);
179                 if (stream.total_out == size && ret == Z_STREAM_END)
180                         break;
181                 if (ret != Z_OK)
182                         bad_object(offset, "inflate returned %d", ret);
183                 stream.next_in = fill(1);
184                 stream.avail_in = input_len;
185         }
186         inflateEnd(&stream);
187         return buf;
188 }
189
190 static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_base)
191 {
192         unsigned char *p, c;
193         unsigned long size;
194         off_t base_offset;
195         unsigned shift;
196         void *data;
197
198         obj->idx.offset = consumed_bytes;
199         input_crc32 = crc32(0, Z_NULL, 0);
200
201         p = fill(1);
202         c = *p;
203         use(1);
204         obj->type = (c >> 4) & 7;
205         size = (c & 15);
206         shift = 4;
207         while (c & 0x80) {
208                 p = fill(1);
209                 c = *p;
210                 use(1);
211                 size += (c & 0x7fUL) << shift;
212                 shift += 7;
213         }
214         obj->size = size;
215
216         switch (obj->type) {
217         case OBJ_REF_DELTA:
218                 hashcpy(delta_base->sha1, fill(20));
219                 use(20);
220                 break;
221         case OBJ_OFS_DELTA:
222                 memset(delta_base, 0, sizeof(*delta_base));
223                 p = fill(1);
224                 c = *p;
225                 use(1);
226                 base_offset = c & 127;
227                 while (c & 128) {
228                         base_offset += 1;
229                         if (!base_offset || MSB(base_offset, 7))
230                                 bad_object(obj->idx.offset, "offset value overflow for delta base object");
231                         p = fill(1);
232                         c = *p;
233                         use(1);
234                         base_offset = (base_offset << 7) + (c & 127);
235                 }
236                 delta_base->offset = obj->idx.offset - base_offset;
237                 if (delta_base->offset >= obj->idx.offset)
238                         bad_object(obj->idx.offset, "delta base offset is out of bound");
239                 break;
240         case OBJ_COMMIT:
241         case OBJ_TREE:
242         case OBJ_BLOB:
243         case OBJ_TAG:
244                 break;
245         default:
246                 bad_object(obj->idx.offset, "unknown object type %d", obj->type);
247         }
248         obj->hdr_size = consumed_bytes - obj->idx.offset;
249
250         data = unpack_entry_data(obj->idx.offset, obj->size);
251         obj->idx.crc32 = input_crc32;
252         return data;
253 }
254
255 static void *get_data_from_pack(struct object_entry *obj)
256 {
257         unsigned long from = obj[0].idx.offset + obj[0].hdr_size;
258         unsigned long len = obj[1].idx.offset - from;
259         unsigned long rdy = 0;
260         unsigned char *src, *data;
261         z_stream stream;
262         int st;
263
264         src = xmalloc(len);
265         data = src;
266         do {
267                 ssize_t n = pread(pack_fd, data + rdy, len - rdy, from + rdy);
268                 if (n <= 0)
269                         die("cannot pread pack file: %s", strerror(errno));
270                 rdy += n;
271         } while (rdy < len);
272         data = xmalloc(obj->size);
273         memset(&stream, 0, sizeof(stream));
274         stream.next_out = data;
275         stream.avail_out = obj->size;
276         stream.next_in = src;
277         stream.avail_in = len;
278         inflateInit(&stream);
279         while ((st = inflate(&stream, Z_FINISH)) == Z_OK);
280         inflateEnd(&stream);
281         if (st != Z_STREAM_END || stream.total_out != obj->size)
282                 die("serious inflate inconsistency");
283         free(src);
284         return data;
285 }
286
287 static int find_delta(const union delta_base *base)
288 {
289         int first = 0, last = nr_deltas;
290
291         while (first < last) {
292                 int next = (first + last) / 2;
293                 struct delta_entry *delta = &deltas[next];
294                 int cmp;
295
296                 cmp = memcmp(base, &delta->base, UNION_BASE_SZ);
297                 if (!cmp)
298                         return next;
299                 if (cmp < 0) {
300                         last = next;
301                         continue;
302                 }
303                 first = next+1;
304         }
305         return -first-1;
306 }
307
308 static int find_delta_children(const union delta_base *base,
309                                int *first_index, int *last_index)
310 {
311         int first = find_delta(base);
312         int last = first;
313         int end = nr_deltas - 1;
314
315         if (first < 0)
316                 return -1;
317         while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
318                 --first;
319         while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
320                 ++last;
321         *first_index = first;
322         *last_index = last;
323         return 0;
324 }
325
326 static void sha1_object(const void *data, unsigned long size,
327                         enum object_type type, unsigned char *sha1)
328 {
329         hash_sha1_file(data, size, typename(type), sha1);
330         if (has_sha1_file(sha1)) {
331                 void *has_data;
332                 enum object_type has_type;
333                 unsigned long has_size;
334                 has_data = read_sha1_file(sha1, &has_type, &has_size);
335                 if (!has_data)
336                         die("cannot read existing object %s", sha1_to_hex(sha1));
337                 if (size != has_size || type != has_type ||
338                     memcmp(data, has_data, size) != 0)
339                         die("SHA1 COLLISION FOUND WITH %s !", sha1_to_hex(sha1));
340                 free(has_data);
341         }
342 }
343
344 static void resolve_delta(struct object_entry *delta_obj, void *base_data,
345                           unsigned long base_size, enum object_type type)
346 {
347         void *delta_data;
348         unsigned long delta_size;
349         void *result;
350         unsigned long result_size;
351         union delta_base delta_base;
352         int j, first, last;
353
354         delta_obj->real_type = type;
355         delta_data = get_data_from_pack(delta_obj);
356         delta_size = delta_obj->size;
357         result = patch_delta(base_data, base_size, delta_data, delta_size,
358                              &result_size);
359         free(delta_data);
360         if (!result)
361                 bad_object(delta_obj->idx.offset, "failed to apply delta");
362         sha1_object(result, result_size, type, delta_obj->idx.sha1);
363         nr_resolved_deltas++;
364
365         hashcpy(delta_base.sha1, delta_obj->idx.sha1);
366         if (!find_delta_children(&delta_base, &first, &last)) {
367                 for (j = first; j <= last; j++) {
368                         struct object_entry *child = objects + deltas[j].obj_no;
369                         if (child->real_type == OBJ_REF_DELTA)
370                                 resolve_delta(child, result, result_size, type);
371                 }
372         }
373
374         memset(&delta_base, 0, sizeof(delta_base));
375         delta_base.offset = delta_obj->idx.offset;
376         if (!find_delta_children(&delta_base, &first, &last)) {
377                 for (j = first; j <= last; j++) {
378                         struct object_entry *child = objects + deltas[j].obj_no;
379                         if (child->real_type == OBJ_OFS_DELTA)
380                                 resolve_delta(child, result, result_size, type);
381                 }
382         }
383
384         free(result);
385 }
386
387 static int compare_delta_entry(const void *a, const void *b)
388 {
389         const struct delta_entry *delta_a = a;
390         const struct delta_entry *delta_b = b;
391         return memcmp(&delta_a->base, &delta_b->base, UNION_BASE_SZ);
392 }
393
394 /* Parse all objects and return the pack content SHA1 hash */
395 static void parse_pack_objects(unsigned char *sha1)
396 {
397         int i;
398         struct delta_entry *delta = deltas;
399         void *data;
400         struct stat st;
401
402         /*
403          * First pass:
404          * - find locations of all objects;
405          * - calculate SHA1 of all non-delta objects;
406          * - remember base (SHA1 or offset) for all deltas.
407          */
408         if (verbose)
409                 start_progress(&progress, "Indexing %u objects...", "", nr_objects);
410         for (i = 0; i < nr_objects; i++) {
411                 struct object_entry *obj = &objects[i];
412                 data = unpack_raw_entry(obj, &delta->base);
413                 obj->real_type = obj->type;
414                 if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
415                         nr_deltas++;
416                         delta->obj_no = i;
417                         delta++;
418                 } else
419                         sha1_object(data, obj->size, obj->type, obj->idx.sha1);
420                 free(data);
421                 if (verbose)
422                         display_progress(&progress, i+1);
423         }
424         objects[i].idx.offset = consumed_bytes;
425         if (verbose)
426                 stop_progress(&progress);
427
428         /* Check pack integrity */
429         flush();
430         SHA1_Final(sha1, &input_ctx);
431         if (hashcmp(fill(20), sha1))
432                 die("pack is corrupted (SHA1 mismatch)");
433         use(20);
434
435         /* If input_fd is a file, we should have reached its end now. */
436         if (fstat(input_fd, &st))
437                 die("cannot fstat packfile: %s", strerror(errno));
438         if (S_ISREG(st.st_mode) &&
439                         lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
440                 die("pack has junk at the end");
441
442         if (!nr_deltas)
443                 return;
444
445         /* Sort deltas by base SHA1/offset for fast searching */
446         qsort(deltas, nr_deltas, sizeof(struct delta_entry),
447               compare_delta_entry);
448
449         /*
450          * Second pass:
451          * - for all non-delta objects, look if it is used as a base for
452          *   deltas;
453          * - if used as a base, uncompress the object and apply all deltas,
454          *   recursively checking if the resulting object is used as a base
455          *   for some more deltas.
456          */
457         if (verbose)
458                 start_progress(&progress, "Resolving %u deltas...", "", nr_deltas);
459         for (i = 0; i < nr_objects; i++) {
460                 struct object_entry *obj = &objects[i];
461                 union delta_base base;
462                 int j, ref, ref_first, ref_last, ofs, ofs_first, ofs_last;
463
464                 if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA)
465                         continue;
466                 hashcpy(base.sha1, obj->idx.sha1);
467                 ref = !find_delta_children(&base, &ref_first, &ref_last);
468                 memset(&base, 0, sizeof(base));
469                 base.offset = obj->idx.offset;
470                 ofs = !find_delta_children(&base, &ofs_first, &ofs_last);
471                 if (!ref && !ofs)
472                         continue;
473                 data = get_data_from_pack(obj);
474                 if (ref)
475                         for (j = ref_first; j <= ref_last; j++) {
476                                 struct object_entry *child = objects + deltas[j].obj_no;
477                                 if (child->real_type == OBJ_REF_DELTA)
478                                         resolve_delta(child, data,
479                                                       obj->size, obj->type);
480                         }
481                 if (ofs)
482                         for (j = ofs_first; j <= ofs_last; j++) {
483                                 struct object_entry *child = objects + deltas[j].obj_no;
484                                 if (child->real_type == OBJ_OFS_DELTA)
485                                         resolve_delta(child, data,
486                                                       obj->size, obj->type);
487                         }
488                 free(data);
489                 if (verbose)
490                         display_progress(&progress, nr_resolved_deltas);
491         }
492 }
493
494 static int write_compressed(int fd, void *in, unsigned int size, uint32_t *obj_crc)
495 {
496         z_stream stream;
497         unsigned long maxsize;
498         void *out;
499
500         memset(&stream, 0, sizeof(stream));
501         deflateInit(&stream, zlib_compression_level);
502         maxsize = deflateBound(&stream, size);
503         out = xmalloc(maxsize);
504
505         /* Compress it */
506         stream.next_in = in;
507         stream.avail_in = size;
508         stream.next_out = out;
509         stream.avail_out = maxsize;
510         while (deflate(&stream, Z_FINISH) == Z_OK);
511         deflateEnd(&stream);
512
513         size = stream.total_out;
514         write_or_die(fd, out, size);
515         *obj_crc = crc32(*obj_crc, out, size);
516         free(out);
517         return size;
518 }
519
520 static void append_obj_to_pack(const unsigned char *sha1, void *buf,
521                                unsigned long size, enum object_type type)
522 {
523         struct object_entry *obj = &objects[nr_objects++];
524         unsigned char header[10];
525         unsigned long s = size;
526         int n = 0;
527         unsigned char c = (type << 4) | (s & 15);
528         s >>= 4;
529         while (s) {
530                 header[n++] = c | 0x80;
531                 c = s & 0x7f;
532                 s >>= 7;
533         }
534         header[n++] = c;
535         write_or_die(output_fd, header, n);
536         obj[0].idx.crc32 = crc32(0, Z_NULL, 0);
537         obj[0].idx.crc32 = crc32(obj[0].idx.crc32, header, n);
538         obj[1].idx.offset = obj[0].idx.offset + n;
539         obj[1].idx.offset += write_compressed(output_fd, buf, size, &obj[0].idx.crc32);
540         hashcpy(obj->idx.sha1, sha1);
541 }
542
543 static int delta_pos_compare(const void *_a, const void *_b)
544 {
545         struct delta_entry *a = *(struct delta_entry **)_a;
546         struct delta_entry *b = *(struct delta_entry **)_b;
547         return a->obj_no - b->obj_no;
548 }
549
550 static void fix_unresolved_deltas(int nr_unresolved)
551 {
552         struct delta_entry **sorted_by_pos;
553         int i, n = 0;
554
555         /*
556          * Since many unresolved deltas may well be themselves base objects
557          * for more unresolved deltas, we really want to include the
558          * smallest number of base objects that would cover as much delta
559          * as possible by picking the
560          * trunc deltas first, allowing for other deltas to resolve without
561          * additional base objects.  Since most base objects are to be found
562          * before deltas depending on them, a good heuristic is to start
563          * resolving deltas in the same order as their position in the pack.
564          */
565         sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
566         for (i = 0; i < nr_deltas; i++) {
567                 if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
568                         continue;
569                 sorted_by_pos[n++] = &deltas[i];
570         }
571         qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
572
573         for (i = 0; i < n; i++) {
574                 struct delta_entry *d = sorted_by_pos[i];
575                 void *data;
576                 unsigned long size;
577                 enum object_type type;
578                 int j, first, last;
579
580                 if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
581                         continue;
582                 data = read_sha1_file(d->base.sha1, &type, &size);
583                 if (!data)
584                         continue;
585
586                 find_delta_children(&d->base, &first, &last);
587                 for (j = first; j <= last; j++) {
588                         struct object_entry *child = objects + deltas[j].obj_no;
589                         if (child->real_type == OBJ_REF_DELTA)
590                                 resolve_delta(child, data, size, type);
591                 }
592
593                 if (check_sha1_signature(d->base.sha1, data, size, typename(type)))
594                         die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
595                 append_obj_to_pack(d->base.sha1, data, size, type);
596                 free(data);
597                 if (verbose)
598                         display_progress(&progress, nr_resolved_deltas);
599         }
600         free(sorted_by_pos);
601 }
602
603 static void final(const char *final_pack_name, const char *curr_pack_name,
604                   const char *final_index_name, const char *curr_index_name,
605                   const char *keep_name, const char *keep_msg,
606                   unsigned char *sha1)
607 {
608         const char *report = "pack";
609         char name[PATH_MAX];
610         int err;
611
612         if (!from_stdin) {
613                 close(input_fd);
614         } else {
615                 err = close(output_fd);
616                 if (err)
617                         die("error while closing pack file: %s", strerror(errno));
618                 chmod(curr_pack_name, 0444);
619         }
620
621         if (keep_msg) {
622                 int keep_fd, keep_msg_len = strlen(keep_msg);
623                 if (!keep_name) {
624                         snprintf(name, sizeof(name), "%s/pack/pack-%s.keep",
625                                  get_object_directory(), sha1_to_hex(sha1));
626                         keep_name = name;
627                 }
628                 keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
629                 if (keep_fd < 0) {
630                         if (errno != EEXIST)
631                                 die("cannot write keep file");
632                 } else {
633                         if (keep_msg_len > 0) {
634                                 write_or_die(keep_fd, keep_msg, keep_msg_len);
635                                 write_or_die(keep_fd, "\n", 1);
636                         }
637                         if (close(keep_fd) != 0)
638                                 die("cannot write keep file");
639                         report = "keep";
640                 }
641         }
642
643         if (final_pack_name != curr_pack_name) {
644                 if (!final_pack_name) {
645                         snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
646                                  get_object_directory(), sha1_to_hex(sha1));
647                         final_pack_name = name;
648                 }
649                 if (move_temp_to_file(curr_pack_name, final_pack_name))
650                         die("cannot store pack file");
651         }
652
653         chmod(curr_index_name, 0444);
654         if (final_index_name != curr_index_name) {
655                 if (!final_index_name) {
656                         snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
657                                  get_object_directory(), sha1_to_hex(sha1));
658                         final_index_name = name;
659                 }
660                 if (move_temp_to_file(curr_index_name, final_index_name))
661                         die("cannot store index file");
662         }
663
664         if (!from_stdin) {
665                 printf("%s\n", sha1_to_hex(sha1));
666         } else {
667                 char buf[48];
668                 int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
669                                    report, sha1_to_hex(sha1));
670                 write_or_die(1, buf, len);
671
672                 /*
673                  * Let's just mimic git-unpack-objects here and write
674                  * the last part of the input buffer to stdout.
675                  */
676                 while (input_len) {
677                         err = xwrite(1, input_buffer + input_offset, input_len);
678                         if (err <= 0)
679                                 break;
680                         input_len -= err;
681                         input_offset += err;
682                 }
683         }
684 }
685
686 int main(int argc, char **argv)
687 {
688         int i, fix_thin_pack = 0;
689         const char *curr_pack, *pack_name = NULL;
690         const char *curr_index, *index_name = NULL;
691         const char *keep_name = NULL, *keep_msg = NULL;
692         char *index_name_buf = NULL, *keep_name_buf = NULL;
693         struct pack_idx_entry **idx_objects;
694         unsigned char sha1[20];
695
696         for (i = 1; i < argc; i++) {
697                 const char *arg = argv[i];
698
699                 if (*arg == '-') {
700                         if (!strcmp(arg, "--stdin")) {
701                                 from_stdin = 1;
702                         } else if (!strcmp(arg, "--fix-thin")) {
703                                 fix_thin_pack = 1;
704                         } else if (!strcmp(arg, "--keep")) {
705                                 keep_msg = "";
706                         } else if (!prefixcmp(arg, "--keep=")) {
707                                 keep_msg = arg + 7;
708                         } else if (!prefixcmp(arg, "--pack_header=")) {
709                                 struct pack_header *hdr;
710                                 char *c;
711
712                                 hdr = (struct pack_header *)input_buffer;
713                                 hdr->hdr_signature = htonl(PACK_SIGNATURE);
714                                 hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
715                                 if (*c != ',')
716                                         die("bad %s", arg);
717                                 hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
718                                 if (*c)
719                                         die("bad %s", arg);
720                                 input_len = sizeof(*hdr);
721                         } else if (!strcmp(arg, "-v")) {
722                                 verbose = 1;
723                         } else if (!strcmp(arg, "-o")) {
724                                 if (index_name || (i+1) >= argc)
725                                         usage(index_pack_usage);
726                                 index_name = argv[++i];
727                         } else if (!prefixcmp(arg, "--index-version=")) {
728                                 char *c;
729                                 pack_idx_default_version = strtoul(arg + 16, &c, 10);
730                                 if (pack_idx_default_version > 2)
731                                         die("bad %s", arg);
732                                 if (*c == ',')
733                                         pack_idx_off32_limit = strtoul(c+1, &c, 0);
734                                 if (*c || pack_idx_off32_limit & 0x80000000)
735                                         die("bad %s", arg);
736                         } else
737                                 usage(index_pack_usage);
738                         continue;
739                 }
740
741                 if (pack_name)
742                         usage(index_pack_usage);
743                 pack_name = arg;
744         }
745
746         if (!pack_name && !from_stdin)
747                 usage(index_pack_usage);
748         if (fix_thin_pack && !from_stdin)
749                 die("--fix-thin cannot be used without --stdin");
750         if (!index_name && pack_name) {
751                 int len = strlen(pack_name);
752                 if (!has_extension(pack_name, ".pack"))
753                         die("packfile name '%s' does not end with '.pack'",
754                             pack_name);
755                 index_name_buf = xmalloc(len);
756                 memcpy(index_name_buf, pack_name, len - 5);
757                 strcpy(index_name_buf + len - 5, ".idx");
758                 index_name = index_name_buf;
759         }
760         if (keep_msg && !keep_name && pack_name) {
761                 int len = strlen(pack_name);
762                 if (!has_extension(pack_name, ".pack"))
763                         die("packfile name '%s' does not end with '.pack'",
764                             pack_name);
765                 keep_name_buf = xmalloc(len);
766                 memcpy(keep_name_buf, pack_name, len - 5);
767                 strcpy(keep_name_buf + len - 5, ".keep");
768                 keep_name = keep_name_buf;
769         }
770
771         curr_pack = open_pack_file(pack_name);
772         parse_pack_header();
773         objects = xmalloc((nr_objects + 1) * sizeof(struct object_entry));
774         deltas = xmalloc(nr_objects * sizeof(struct delta_entry));
775         parse_pack_objects(sha1);
776         if (nr_deltas == nr_resolved_deltas) {
777                 if (verbose)
778                         stop_progress(&progress);
779                 /* Flush remaining pack final 20-byte SHA1. */
780                 flush();
781         } else {
782                 if (fix_thin_pack) {
783                         int nr_unresolved = nr_deltas - nr_resolved_deltas;
784                         int nr_objects_initial = nr_objects;
785                         if (nr_unresolved <= 0)
786                                 die("confusion beyond insanity");
787                         objects = xrealloc(objects,
788                                            (nr_objects + nr_unresolved + 1)
789                                            * sizeof(*objects));
790                         fix_unresolved_deltas(nr_unresolved);
791                         if (verbose) {
792                                 stop_progress(&progress);
793                                 fprintf(stderr, "%d objects were added to complete this thin pack.\n",
794                                         nr_objects - nr_objects_initial);
795                         }
796                         fixup_pack_header_footer(output_fd, sha1,
797                                 curr_pack, nr_objects);
798                 }
799                 if (nr_deltas != nr_resolved_deltas)
800                         die("pack has %d unresolved deltas",
801                             nr_deltas - nr_resolved_deltas);
802         }
803         free(deltas);
804
805         idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
806         for (i = 0; i < nr_objects; i++)
807                 idx_objects[i] = &objects[i].idx;
808         curr_index = write_idx_file(index_name, idx_objects, nr_objects, sha1);
809         free(idx_objects);
810
811         final(pack_name, curr_pack,
812                 index_name, curr_index,
813                 keep_name, keep_msg,
814                 sha1);
815         free(objects);
816         free(index_name_buf);
817         free(keep_name_buf);
818
819         return 0;
820 }