Merge branch 'russian-l10n' of https://github.com/DJm00n/git-po-ru
[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 #include "streaming.h"
13 #include "thread-utils.h"
14
15 static const char index_pack_usage[] =
16 "git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
17
18 struct object_entry {
19         struct pack_idx_entry idx;
20         unsigned long size;
21         unsigned char hdr_size;
22         signed char type;
23         signed char real_type;
24 };
25
26 struct object_stat {
27         unsigned delta_depth;
28         int base_object_no;
29 };
30
31 struct base_data {
32         struct base_data *base;
33         struct base_data *child;
34         struct object_entry *obj;
35         void *data;
36         unsigned long size;
37         int ref_first, ref_last;
38         int ofs_first, ofs_last;
39 };
40
41 struct thread_local {
42 #ifndef NO_PTHREADS
43         pthread_t thread;
44 #endif
45         struct base_data *base_cache;
46         size_t base_cache_used;
47         int pack_fd;
48 };
49
50 #define FLAG_LINK (1u<<20)
51 #define FLAG_CHECKED (1u<<21)
52
53 struct ofs_delta_entry {
54         off_t offset;
55         int obj_no;
56 };
57
58 struct ref_delta_entry {
59         unsigned char sha1[20];
60         int obj_no;
61 };
62
63 static struct object_entry *objects;
64 static struct object_stat *obj_stat;
65 static struct ofs_delta_entry *ofs_deltas;
66 static struct ref_delta_entry *ref_deltas;
67 static struct thread_local nothread_data;
68 static int nr_objects;
69 static int nr_ofs_deltas;
70 static int nr_ref_deltas;
71 static int ref_deltas_alloc;
72 static int nr_resolved_deltas;
73 static int nr_threads;
74
75 static int from_stdin;
76 static int strict;
77 static int do_fsck_object;
78 static struct fsck_options fsck_options = FSCK_OPTIONS_STRICT;
79 static int verbose;
80 static int show_resolving_progress;
81 static int show_stat;
82 static int check_self_contained_and_connected;
83
84 static struct progress *progress;
85
86 /* We always read in 4kB chunks. */
87 static unsigned char input_buffer[4096];
88 static unsigned int input_offset, input_len;
89 static off_t consumed_bytes;
90 static unsigned deepest_delta;
91 static git_SHA_CTX input_ctx;
92 static uint32_t input_crc32;
93 static int input_fd, output_fd;
94 static const char *curr_pack;
95
96 #ifndef NO_PTHREADS
97
98 static struct thread_local *thread_data;
99 static int nr_dispatched;
100 static int threads_active;
101
102 static pthread_mutex_t read_mutex;
103 #define read_lock()             lock_mutex(&read_mutex)
104 #define read_unlock()           unlock_mutex(&read_mutex)
105
106 static pthread_mutex_t counter_mutex;
107 #define counter_lock()          lock_mutex(&counter_mutex)
108 #define counter_unlock()        unlock_mutex(&counter_mutex)
109
110 static pthread_mutex_t work_mutex;
111 #define work_lock()             lock_mutex(&work_mutex)
112 #define work_unlock()           unlock_mutex(&work_mutex)
113
114 static pthread_mutex_t deepest_delta_mutex;
115 #define deepest_delta_lock()    lock_mutex(&deepest_delta_mutex)
116 #define deepest_delta_unlock()  unlock_mutex(&deepest_delta_mutex)
117
118 static pthread_mutex_t type_cas_mutex;
119 #define type_cas_lock()         lock_mutex(&type_cas_mutex)
120 #define type_cas_unlock()       unlock_mutex(&type_cas_mutex)
121
122 static pthread_key_t key;
123
124 static inline void lock_mutex(pthread_mutex_t *mutex)
125 {
126         if (threads_active)
127                 pthread_mutex_lock(mutex);
128 }
129
130 static inline void unlock_mutex(pthread_mutex_t *mutex)
131 {
132         if (threads_active)
133                 pthread_mutex_unlock(mutex);
134 }
135
136 /*
137  * Mutex and conditional variable can't be statically-initialized on Windows.
138  */
139 static void init_thread(void)
140 {
141         int i;
142         init_recursive_mutex(&read_mutex);
143         pthread_mutex_init(&counter_mutex, NULL);
144         pthread_mutex_init(&work_mutex, NULL);
145         pthread_mutex_init(&type_cas_mutex, NULL);
146         if (show_stat)
147                 pthread_mutex_init(&deepest_delta_mutex, NULL);
148         pthread_key_create(&key, NULL);
149         thread_data = xcalloc(nr_threads, sizeof(*thread_data));
150         for (i = 0; i < nr_threads; i++) {
151                 thread_data[i].pack_fd = open(curr_pack, O_RDONLY);
152                 if (thread_data[i].pack_fd == -1)
153                         die_errno(_("unable to open %s"), curr_pack);
154         }
155
156         threads_active = 1;
157 }
158
159 static void cleanup_thread(void)
160 {
161         int i;
162         if (!threads_active)
163                 return;
164         threads_active = 0;
165         pthread_mutex_destroy(&read_mutex);
166         pthread_mutex_destroy(&counter_mutex);
167         pthread_mutex_destroy(&work_mutex);
168         pthread_mutex_destroy(&type_cas_mutex);
169         if (show_stat)
170                 pthread_mutex_destroy(&deepest_delta_mutex);
171         for (i = 0; i < nr_threads; i++)
172                 close(thread_data[i].pack_fd);
173         pthread_key_delete(key);
174         free(thread_data);
175 }
176
177 #else
178
179 #define read_lock()
180 #define read_unlock()
181
182 #define counter_lock()
183 #define counter_unlock()
184
185 #define work_lock()
186 #define work_unlock()
187
188 #define deepest_delta_lock()
189 #define deepest_delta_unlock()
190
191 #define type_cas_lock()
192 #define type_cas_unlock()
193
194 #endif
195
196
197 static int mark_link(struct object *obj, int type, void *data, struct fsck_options *options)
198 {
199         if (!obj)
200                 return -1;
201
202         if (type != OBJ_ANY && obj->type != type)
203                 die(_("object type mismatch at %s"), oid_to_hex(&obj->oid));
204
205         obj->flags |= FLAG_LINK;
206         return 0;
207 }
208
209 /* The content of each linked object must have been checked
210    or it must be already present in the object database */
211 static unsigned check_object(struct object *obj)
212 {
213         if (!obj)
214                 return 0;
215
216         if (!(obj->flags & FLAG_LINK))
217                 return 0;
218
219         if (!(obj->flags & FLAG_CHECKED)) {
220                 unsigned long size;
221                 int type = sha1_object_info(obj->oid.hash, &size);
222                 if (type <= 0)
223                         die(_("did not receive expected object %s"),
224                               oid_to_hex(&obj->oid));
225                 if (type != obj->type)
226                         die(_("object %s: expected type %s, found %s"),
227                             oid_to_hex(&obj->oid),
228                             typename(obj->type), typename(type));
229                 obj->flags |= FLAG_CHECKED;
230                 return 1;
231         }
232
233         return 0;
234 }
235
236 static unsigned check_objects(void)
237 {
238         unsigned i, max, foreign_nr = 0;
239
240         max = get_max_object_index();
241         for (i = 0; i < max; i++)
242                 foreign_nr += check_object(get_indexed_object(i));
243         return foreign_nr;
244 }
245
246
247 /* Discard current buffer used content. */
248 static void flush(void)
249 {
250         if (input_offset) {
251                 if (output_fd >= 0)
252                         write_or_die(output_fd, input_buffer, input_offset);
253                 git_SHA1_Update(&input_ctx, input_buffer, input_offset);
254                 memmove(input_buffer, input_buffer + input_offset, input_len);
255                 input_offset = 0;
256         }
257 }
258
259 /*
260  * Make sure at least "min" bytes are available in the buffer, and
261  * return the pointer to the buffer.
262  */
263 static void *fill(int min)
264 {
265         if (min <= input_len)
266                 return input_buffer + input_offset;
267         if (min > sizeof(input_buffer))
268                 die(Q_("cannot fill %d byte",
269                        "cannot fill %d bytes",
270                        min),
271                     min);
272         flush();
273         do {
274                 ssize_t ret = xread(input_fd, input_buffer + input_len,
275                                 sizeof(input_buffer) - input_len);
276                 if (ret <= 0) {
277                         if (!ret)
278                                 die(_("early EOF"));
279                         die_errno(_("read error on input"));
280                 }
281                 input_len += ret;
282                 if (from_stdin)
283                         display_throughput(progress, consumed_bytes + input_len);
284         } while (input_len < min);
285         return input_buffer;
286 }
287
288 static void use(int bytes)
289 {
290         if (bytes > input_len)
291                 die(_("used more bytes than were available"));
292         input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
293         input_len -= bytes;
294         input_offset += bytes;
295
296         /* make sure off_t is sufficiently large not to wrap */
297         if (signed_add_overflows(consumed_bytes, bytes))
298                 die(_("pack too large for current definition of off_t"));
299         consumed_bytes += bytes;
300 }
301
302 static const char *open_pack_file(const char *pack_name)
303 {
304         if (from_stdin) {
305                 input_fd = 0;
306                 if (!pack_name) {
307                         static char tmp_file[PATH_MAX];
308                         output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
309                                                 "pack/tmp_pack_XXXXXX");
310                         pack_name = xstrdup(tmp_file);
311                 } else
312                         output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
313                 if (output_fd < 0)
314                         die_errno(_("unable to create '%s'"), pack_name);
315                 nothread_data.pack_fd = output_fd;
316         } else {
317                 input_fd = open(pack_name, O_RDONLY);
318                 if (input_fd < 0)
319                         die_errno(_("cannot open packfile '%s'"), pack_name);
320                 output_fd = -1;
321                 nothread_data.pack_fd = input_fd;
322         }
323         git_SHA1_Init(&input_ctx);
324         return pack_name;
325 }
326
327 static void parse_pack_header(void)
328 {
329         struct pack_header *hdr = fill(sizeof(struct pack_header));
330
331         /* Header consistency check */
332         if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
333                 die(_("pack signature mismatch"));
334         if (!pack_version_ok(hdr->hdr_version))
335                 die(_("pack version %"PRIu32" unsupported"),
336                         ntohl(hdr->hdr_version));
337
338         nr_objects = ntohl(hdr->hdr_entries);
339         use(sizeof(struct pack_header));
340 }
341
342 static NORETURN void bad_object(off_t offset, const char *format,
343                        ...) __attribute__((format (printf, 2, 3)));
344
345 static NORETURN void bad_object(off_t offset, const char *format, ...)
346 {
347         va_list params;
348         char buf[1024];
349
350         va_start(params, format);
351         vsnprintf(buf, sizeof(buf), format, params);
352         va_end(params);
353         die(_("pack has bad object at offset %"PRIuMAX": %s"),
354             (uintmax_t)offset, buf);
355 }
356
357 static inline struct thread_local *get_thread_data(void)
358 {
359 #ifndef NO_PTHREADS
360         if (threads_active)
361                 return pthread_getspecific(key);
362         assert(!threads_active &&
363                "This should only be reached when all threads are gone");
364 #endif
365         return &nothread_data;
366 }
367
368 #ifndef NO_PTHREADS
369 static void set_thread_data(struct thread_local *data)
370 {
371         if (threads_active)
372                 pthread_setspecific(key, data);
373 }
374 #endif
375
376 static struct base_data *alloc_base_data(void)
377 {
378         struct base_data *base = xcalloc(1, sizeof(struct base_data));
379         base->ref_last = -1;
380         base->ofs_last = -1;
381         return base;
382 }
383
384 static void free_base_data(struct base_data *c)
385 {
386         if (c->data) {
387                 free(c->data);
388                 c->data = NULL;
389                 get_thread_data()->base_cache_used -= c->size;
390         }
391 }
392
393 static void prune_base_data(struct base_data *retain)
394 {
395         struct base_data *b;
396         struct thread_local *data = get_thread_data();
397         for (b = data->base_cache;
398              data->base_cache_used > delta_base_cache_limit && b;
399              b = b->child) {
400                 if (b->data && b != retain)
401                         free_base_data(b);
402         }
403 }
404
405 static void link_base_data(struct base_data *base, struct base_data *c)
406 {
407         if (base)
408                 base->child = c;
409         else
410                 get_thread_data()->base_cache = c;
411
412         c->base = base;
413         c->child = NULL;
414         if (c->data)
415                 get_thread_data()->base_cache_used += c->size;
416         prune_base_data(c);
417 }
418
419 static void unlink_base_data(struct base_data *c)
420 {
421         struct base_data *base = c->base;
422         if (base)
423                 base->child = NULL;
424         else
425                 get_thread_data()->base_cache = NULL;
426         free_base_data(c);
427 }
428
429 static int is_delta_type(enum object_type type)
430 {
431         return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
432 }
433
434 static void *unpack_entry_data(off_t offset, unsigned long size,
435                                enum object_type type, unsigned char *sha1)
436 {
437         static char fixed_buf[8192];
438         int status;
439         git_zstream stream;
440         void *buf;
441         git_SHA_CTX c;
442         char hdr[32];
443         int hdrlen;
444
445         if (!is_delta_type(type)) {
446                 hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(type), size) + 1;
447                 git_SHA1_Init(&c);
448                 git_SHA1_Update(&c, hdr, hdrlen);
449         } else
450                 sha1 = NULL;
451         if (type == OBJ_BLOB && size > big_file_threshold)
452                 buf = fixed_buf;
453         else
454                 buf = xmallocz(size);
455
456         memset(&stream, 0, sizeof(stream));
457         git_inflate_init(&stream);
458         stream.next_out = buf;
459         stream.avail_out = buf == fixed_buf ? sizeof(fixed_buf) : size;
460
461         do {
462                 unsigned char *last_out = stream.next_out;
463                 stream.next_in = fill(1);
464                 stream.avail_in = input_len;
465                 status = git_inflate(&stream, 0);
466                 use(input_len - stream.avail_in);
467                 if (sha1)
468                         git_SHA1_Update(&c, last_out, stream.next_out - last_out);
469                 if (buf == fixed_buf) {
470                         stream.next_out = buf;
471                         stream.avail_out = sizeof(fixed_buf);
472                 }
473         } while (status == Z_OK);
474         if (stream.total_out != size || status != Z_STREAM_END)
475                 bad_object(offset, _("inflate returned %d"), status);
476         git_inflate_end(&stream);
477         if (sha1)
478                 git_SHA1_Final(sha1, &c);
479         return buf == fixed_buf ? NULL : buf;
480 }
481
482 static void *unpack_raw_entry(struct object_entry *obj,
483                               off_t *ofs_offset,
484                               unsigned char *ref_sha1,
485                               unsigned char *sha1)
486 {
487         unsigned char *p;
488         unsigned long size, c;
489         off_t base_offset;
490         unsigned shift;
491         void *data;
492
493         obj->idx.offset = consumed_bytes;
494         input_crc32 = crc32(0, NULL, 0);
495
496         p = fill(1);
497         c = *p;
498         use(1);
499         obj->type = (c >> 4) & 7;
500         size = (c & 15);
501         shift = 4;
502         while (c & 0x80) {
503                 p = fill(1);
504                 c = *p;
505                 use(1);
506                 size += (c & 0x7f) << shift;
507                 shift += 7;
508         }
509         obj->size = size;
510
511         switch (obj->type) {
512         case OBJ_REF_DELTA:
513                 hashcpy(ref_sha1, fill(20));
514                 use(20);
515                 break;
516         case OBJ_OFS_DELTA:
517                 p = fill(1);
518                 c = *p;
519                 use(1);
520                 base_offset = c & 127;
521                 while (c & 128) {
522                         base_offset += 1;
523                         if (!base_offset || MSB(base_offset, 7))
524                                 bad_object(obj->idx.offset, _("offset value overflow for delta base object"));
525                         p = fill(1);
526                         c = *p;
527                         use(1);
528                         base_offset = (base_offset << 7) + (c & 127);
529                 }
530                 *ofs_offset = obj->idx.offset - base_offset;
531                 if (*ofs_offset <= 0 || *ofs_offset >= obj->idx.offset)
532                         bad_object(obj->idx.offset, _("delta base offset is out of bound"));
533                 break;
534         case OBJ_COMMIT:
535         case OBJ_TREE:
536         case OBJ_BLOB:
537         case OBJ_TAG:
538                 break;
539         default:
540                 bad_object(obj->idx.offset, _("unknown object type %d"), obj->type);
541         }
542         obj->hdr_size = consumed_bytes - obj->idx.offset;
543
544         data = unpack_entry_data(obj->idx.offset, obj->size, obj->type, sha1);
545         obj->idx.crc32 = input_crc32;
546         return data;
547 }
548
549 static void *unpack_data(struct object_entry *obj,
550                          int (*consume)(const unsigned char *, unsigned long, void *),
551                          void *cb_data)
552 {
553         off_t from = obj[0].idx.offset + obj[0].hdr_size;
554         off_t len = obj[1].idx.offset - from;
555         unsigned char *data, *inbuf;
556         git_zstream stream;
557         int status;
558
559         data = xmallocz(consume ? 64*1024 : obj->size);
560         inbuf = xmalloc((len < 64*1024) ? (int)len : 64*1024);
561
562         memset(&stream, 0, sizeof(stream));
563         git_inflate_init(&stream);
564         stream.next_out = data;
565         stream.avail_out = consume ? 64*1024 : obj->size;
566
567         do {
568                 ssize_t n = (len < 64*1024) ? (ssize_t)len : 64*1024;
569                 n = xpread(get_thread_data()->pack_fd, inbuf, n, from);
570                 if (n < 0)
571                         die_errno(_("cannot pread pack file"));
572                 if (!n)
573                         die(Q_("premature end of pack file, %"PRIuMAX" byte missing",
574                                "premature end of pack file, %"PRIuMAX" bytes missing",
575                                (unsigned int)len),
576                             (uintmax_t)len);
577                 from += n;
578                 len -= n;
579                 stream.next_in = inbuf;
580                 stream.avail_in = n;
581                 if (!consume)
582                         status = git_inflate(&stream, 0);
583                 else {
584                         do {
585                                 status = git_inflate(&stream, 0);
586                                 if (consume(data, stream.next_out - data, cb_data)) {
587                                         free(inbuf);
588                                         free(data);
589                                         return NULL;
590                                 }
591                                 stream.next_out = data;
592                                 stream.avail_out = 64*1024;
593                         } while (status == Z_OK && stream.avail_in);
594                 }
595         } while (len && status == Z_OK && !stream.avail_in);
596
597         /* This has been inflated OK when first encountered, so... */
598         if (status != Z_STREAM_END || stream.total_out != obj->size)
599                 die(_("serious inflate inconsistency"));
600
601         git_inflate_end(&stream);
602         free(inbuf);
603         if (consume) {
604                 free(data);
605                 data = NULL;
606         }
607         return data;
608 }
609
610 static void *get_data_from_pack(struct object_entry *obj)
611 {
612         return unpack_data(obj, NULL, NULL);
613 }
614
615 static int compare_ofs_delta_bases(off_t offset1, off_t offset2,
616                                    enum object_type type1,
617                                    enum object_type type2)
618 {
619         int cmp = type1 - type2;
620         if (cmp)
621                 return cmp;
622         return offset1 < offset2 ? -1 :
623                offset1 > offset2 ?  1 :
624                0;
625 }
626
627 static int find_ofs_delta(const off_t offset, enum object_type type)
628 {
629         int first = 0, last = nr_ofs_deltas;
630
631         while (first < last) {
632                 int next = (first + last) / 2;
633                 struct ofs_delta_entry *delta = &ofs_deltas[next];
634                 int cmp;
635
636                 cmp = compare_ofs_delta_bases(offset, delta->offset,
637                                               type, objects[delta->obj_no].type);
638                 if (!cmp)
639                         return next;
640                 if (cmp < 0) {
641                         last = next;
642                         continue;
643                 }
644                 first = next+1;
645         }
646         return -first-1;
647 }
648
649 static void find_ofs_delta_children(off_t offset,
650                                     int *first_index, int *last_index,
651                                     enum object_type type)
652 {
653         int first = find_ofs_delta(offset, type);
654         int last = first;
655         int end = nr_ofs_deltas - 1;
656
657         if (first < 0) {
658                 *first_index = 0;
659                 *last_index = -1;
660                 return;
661         }
662         while (first > 0 && ofs_deltas[first - 1].offset == offset)
663                 --first;
664         while (last < end && ofs_deltas[last + 1].offset == offset)
665                 ++last;
666         *first_index = first;
667         *last_index = last;
668 }
669
670 static int compare_ref_delta_bases(const unsigned char *sha1,
671                                    const unsigned char *sha2,
672                                    enum object_type type1,
673                                    enum object_type type2)
674 {
675         int cmp = type1 - type2;
676         if (cmp)
677                 return cmp;
678         return hashcmp(sha1, sha2);
679 }
680
681 static int find_ref_delta(const unsigned char *sha1, enum object_type type)
682 {
683         int first = 0, last = nr_ref_deltas;
684
685         while (first < last) {
686                 int next = (first + last) / 2;
687                 struct ref_delta_entry *delta = &ref_deltas[next];
688                 int cmp;
689
690                 cmp = compare_ref_delta_bases(sha1, delta->sha1,
691                                               type, objects[delta->obj_no].type);
692                 if (!cmp)
693                         return next;
694                 if (cmp < 0) {
695                         last = next;
696                         continue;
697                 }
698                 first = next+1;
699         }
700         return -first-1;
701 }
702
703 static void find_ref_delta_children(const unsigned char *sha1,
704                                     int *first_index, int *last_index,
705                                     enum object_type type)
706 {
707         int first = find_ref_delta(sha1, type);
708         int last = first;
709         int end = nr_ref_deltas - 1;
710
711         if (first < 0) {
712                 *first_index = 0;
713                 *last_index = -1;
714                 return;
715         }
716         while (first > 0 && !hashcmp(ref_deltas[first - 1].sha1, sha1))
717                 --first;
718         while (last < end && !hashcmp(ref_deltas[last + 1].sha1, sha1))
719                 ++last;
720         *first_index = first;
721         *last_index = last;
722 }
723
724 struct compare_data {
725         struct object_entry *entry;
726         struct git_istream *st;
727         unsigned char *buf;
728         unsigned long buf_size;
729 };
730
731 static int compare_objects(const unsigned char *buf, unsigned long size,
732                            void *cb_data)
733 {
734         struct compare_data *data = cb_data;
735
736         if (data->buf_size < size) {
737                 free(data->buf);
738                 data->buf = xmalloc(size);
739                 data->buf_size = size;
740         }
741
742         while (size) {
743                 ssize_t len = read_istream(data->st, data->buf, size);
744                 if (len == 0)
745                         die(_("SHA1 COLLISION FOUND WITH %s !"),
746                             sha1_to_hex(data->entry->idx.sha1));
747                 if (len < 0)
748                         die(_("unable to read %s"),
749                             sha1_to_hex(data->entry->idx.sha1));
750                 if (memcmp(buf, data->buf, len))
751                         die(_("SHA1 COLLISION FOUND WITH %s !"),
752                             sha1_to_hex(data->entry->idx.sha1));
753                 size -= len;
754                 buf += len;
755         }
756         return 0;
757 }
758
759 static int check_collison(struct object_entry *entry)
760 {
761         struct compare_data data;
762         enum object_type type;
763         unsigned long size;
764
765         if (entry->size <= big_file_threshold || entry->type != OBJ_BLOB)
766                 return -1;
767
768         memset(&data, 0, sizeof(data));
769         data.entry = entry;
770         data.st = open_istream(entry->idx.sha1, &type, &size, NULL);
771         if (!data.st)
772                 return -1;
773         if (size != entry->size || type != entry->type)
774                 die(_("SHA1 COLLISION FOUND WITH %s !"),
775                     sha1_to_hex(entry->idx.sha1));
776         unpack_data(entry, compare_objects, &data);
777         close_istream(data.st);
778         free(data.buf);
779         return 0;
780 }
781
782 static void sha1_object(const void *data, struct object_entry *obj_entry,
783                         unsigned long size, enum object_type type,
784                         const unsigned char *sha1)
785 {
786         void *new_data = NULL;
787         int collision_test_needed;
788
789         assert(data || obj_entry);
790
791         read_lock();
792         collision_test_needed = has_sha1_file_with_flags(sha1, HAS_SHA1_QUICK);
793         read_unlock();
794
795         if (collision_test_needed && !data) {
796                 read_lock();
797                 if (!check_collison(obj_entry))
798                         collision_test_needed = 0;
799                 read_unlock();
800         }
801         if (collision_test_needed) {
802                 void *has_data;
803                 enum object_type has_type;
804                 unsigned long has_size;
805                 read_lock();
806                 has_type = sha1_object_info(sha1, &has_size);
807                 if (has_type != type || has_size != size)
808                         die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
809                 has_data = read_sha1_file(sha1, &has_type, &has_size);
810                 read_unlock();
811                 if (!data)
812                         data = new_data = get_data_from_pack(obj_entry);
813                 if (!has_data)
814                         die(_("cannot read existing object %s"), sha1_to_hex(sha1));
815                 if (size != has_size || type != has_type ||
816                     memcmp(data, has_data, size) != 0)
817                         die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
818                 free(has_data);
819         }
820
821         if (strict) {
822                 read_lock();
823                 if (type == OBJ_BLOB) {
824                         struct blob *blob = lookup_blob(sha1);
825                         if (blob)
826                                 blob->object.flags |= FLAG_CHECKED;
827                         else
828                                 die(_("invalid blob object %s"), sha1_to_hex(sha1));
829                 } else {
830                         struct object *obj;
831                         int eaten;
832                         void *buf = (void *) data;
833
834                         assert(data && "data can only be NULL for large _blobs_");
835
836                         /*
837                          * we do not need to free the memory here, as the
838                          * buf is deleted by the caller.
839                          */
840                         obj = parse_object_buffer(sha1, type, size, buf, &eaten);
841                         if (!obj)
842                                 die(_("invalid %s"), typename(type));
843                         if (do_fsck_object &&
844                             fsck_object(obj, buf, size, &fsck_options))
845                                 die(_("Error in object"));
846                         if (fsck_walk(obj, NULL, &fsck_options))
847                                 die(_("Not all child objects of %s are reachable"), oid_to_hex(&obj->oid));
848
849                         if (obj->type == OBJ_TREE) {
850                                 struct tree *item = (struct tree *) obj;
851                                 item->buffer = NULL;
852                                 obj->parsed = 0;
853                         }
854                         if (obj->type == OBJ_COMMIT) {
855                                 struct commit *commit = (struct commit *) obj;
856                                 if (detach_commit_buffer(commit, NULL) != data)
857                                         die("BUG: parse_object_buffer transmogrified our buffer");
858                         }
859                         obj->flags |= FLAG_CHECKED;
860                 }
861                 read_unlock();
862         }
863
864         free(new_data);
865 }
866
867 /*
868  * This function is part of find_unresolved_deltas(). There are two
869  * walkers going in the opposite ways.
870  *
871  * The first one in find_unresolved_deltas() traverses down from
872  * parent node to children, deflating nodes along the way. However,
873  * memory for deflated nodes is limited by delta_base_cache_limit, so
874  * at some point parent node's deflated content may be freed.
875  *
876  * The second walker is this function, which goes from current node up
877  * to top parent if necessary to deflate the node. In normal
878  * situation, its parent node would be already deflated, so it just
879  * needs to apply delta.
880  *
881  * In the worst case scenario, parent node is no longer deflated because
882  * we're running out of delta_base_cache_limit; we need to re-deflate
883  * parents, possibly up to the top base.
884  *
885  * All deflated objects here are subject to be freed if we exceed
886  * delta_base_cache_limit, just like in find_unresolved_deltas(), we
887  * just need to make sure the last node is not freed.
888  */
889 static void *get_base_data(struct base_data *c)
890 {
891         if (!c->data) {
892                 struct object_entry *obj = c->obj;
893                 struct base_data **delta = NULL;
894                 int delta_nr = 0, delta_alloc = 0;
895
896                 while (is_delta_type(c->obj->type) && !c->data) {
897                         ALLOC_GROW(delta, delta_nr + 1, delta_alloc);
898                         delta[delta_nr++] = c;
899                         c = c->base;
900                 }
901                 if (!delta_nr) {
902                         c->data = get_data_from_pack(obj);
903                         c->size = obj->size;
904                         get_thread_data()->base_cache_used += c->size;
905                         prune_base_data(c);
906                 }
907                 for (; delta_nr > 0; delta_nr--) {
908                         void *base, *raw;
909                         c = delta[delta_nr - 1];
910                         obj = c->obj;
911                         base = get_base_data(c->base);
912                         raw = get_data_from_pack(obj);
913                         c->data = patch_delta(
914                                 base, c->base->size,
915                                 raw, obj->size,
916                                 &c->size);
917                         free(raw);
918                         if (!c->data)
919                                 bad_object(obj->idx.offset, _("failed to apply delta"));
920                         get_thread_data()->base_cache_used += c->size;
921                         prune_base_data(c);
922                 }
923                 free(delta);
924         }
925         return c->data;
926 }
927
928 static void resolve_delta(struct object_entry *delta_obj,
929                           struct base_data *base, struct base_data *result)
930 {
931         void *base_data, *delta_data;
932
933         if (show_stat) {
934                 int i = delta_obj - objects;
935                 int j = base->obj - objects;
936                 obj_stat[i].delta_depth = obj_stat[j].delta_depth + 1;
937                 deepest_delta_lock();
938                 if (deepest_delta < obj_stat[i].delta_depth)
939                         deepest_delta = obj_stat[i].delta_depth;
940                 deepest_delta_unlock();
941                 obj_stat[i].base_object_no = j;
942         }
943         delta_data = get_data_from_pack(delta_obj);
944         base_data = get_base_data(base);
945         result->obj = delta_obj;
946         result->data = patch_delta(base_data, base->size,
947                                    delta_data, delta_obj->size, &result->size);
948         free(delta_data);
949         if (!result->data)
950                 bad_object(delta_obj->idx.offset, _("failed to apply delta"));
951         hash_sha1_file(result->data, result->size,
952                        typename(delta_obj->real_type), delta_obj->idx.sha1);
953         sha1_object(result->data, NULL, result->size, delta_obj->real_type,
954                     delta_obj->idx.sha1);
955         counter_lock();
956         nr_resolved_deltas++;
957         counter_unlock();
958 }
959
960 /*
961  * Standard boolean compare-and-swap: atomically check whether "*type" is
962  * "want"; if so, swap in "set" and return true. Otherwise, leave it untouched
963  * and return false.
964  */
965 static int compare_and_swap_type(signed char *type,
966                                  enum object_type want,
967                                  enum object_type set)
968 {
969         enum object_type old;
970
971         type_cas_lock();
972         old = *type;
973         if (old == want)
974                 *type = set;
975         type_cas_unlock();
976
977         return old == want;
978 }
979
980 static struct base_data *find_unresolved_deltas_1(struct base_data *base,
981                                                   struct base_data *prev_base)
982 {
983         if (base->ref_last == -1 && base->ofs_last == -1) {
984                 find_ref_delta_children(base->obj->idx.sha1,
985                                         &base->ref_first, &base->ref_last,
986                                         OBJ_REF_DELTA);
987
988                 find_ofs_delta_children(base->obj->idx.offset,
989                                         &base->ofs_first, &base->ofs_last,
990                                         OBJ_OFS_DELTA);
991
992                 if (base->ref_last == -1 && base->ofs_last == -1) {
993                         free(base->data);
994                         return NULL;
995                 }
996
997                 link_base_data(prev_base, base);
998         }
999
1000         if (base->ref_first <= base->ref_last) {
1001                 struct object_entry *child = objects + ref_deltas[base->ref_first].obj_no;
1002                 struct base_data *result = alloc_base_data();
1003
1004                 if (!compare_and_swap_type(&child->real_type, OBJ_REF_DELTA,
1005                                            base->obj->real_type))
1006                         die("BUG: child->real_type != OBJ_REF_DELTA");
1007
1008                 resolve_delta(child, base, result);
1009                 if (base->ref_first == base->ref_last && base->ofs_last == -1)
1010                         free_base_data(base);
1011
1012                 base->ref_first++;
1013                 return result;
1014         }
1015
1016         if (base->ofs_first <= base->ofs_last) {
1017                 struct object_entry *child = objects + ofs_deltas[base->ofs_first].obj_no;
1018                 struct base_data *result = alloc_base_data();
1019
1020                 assert(child->real_type == OBJ_OFS_DELTA);
1021                 child->real_type = base->obj->real_type;
1022                 resolve_delta(child, base, result);
1023                 if (base->ofs_first == base->ofs_last)
1024                         free_base_data(base);
1025
1026                 base->ofs_first++;
1027                 return result;
1028         }
1029
1030         unlink_base_data(base);
1031         return NULL;
1032 }
1033
1034 static void find_unresolved_deltas(struct base_data *base)
1035 {
1036         struct base_data *new_base, *prev_base = NULL;
1037         for (;;) {
1038                 new_base = find_unresolved_deltas_1(base, prev_base);
1039
1040                 if (new_base) {
1041                         prev_base = base;
1042                         base = new_base;
1043                 } else {
1044                         free(base);
1045                         base = prev_base;
1046                         if (!base)
1047                                 return;
1048                         prev_base = base->base;
1049                 }
1050         }
1051 }
1052
1053 static int compare_ofs_delta_entry(const void *a, const void *b)
1054 {
1055         const struct ofs_delta_entry *delta_a = a;
1056         const struct ofs_delta_entry *delta_b = b;
1057
1058         return delta_a->offset < delta_b->offset ? -1 :
1059                delta_a->offset > delta_b->offset ?  1 :
1060                0;
1061 }
1062
1063 static int compare_ref_delta_entry(const void *a, const void *b)
1064 {
1065         const struct ref_delta_entry *delta_a = a;
1066         const struct ref_delta_entry *delta_b = b;
1067
1068         return hashcmp(delta_a->sha1, delta_b->sha1);
1069 }
1070
1071 static void resolve_base(struct object_entry *obj)
1072 {
1073         struct base_data *base_obj = alloc_base_data();
1074         base_obj->obj = obj;
1075         base_obj->data = NULL;
1076         find_unresolved_deltas(base_obj);
1077 }
1078
1079 #ifndef NO_PTHREADS
1080 static void *threaded_second_pass(void *data)
1081 {
1082         set_thread_data(data);
1083         for (;;) {
1084                 int i;
1085                 counter_lock();
1086                 display_progress(progress, nr_resolved_deltas);
1087                 counter_unlock();
1088                 work_lock();
1089                 while (nr_dispatched < nr_objects &&
1090                        is_delta_type(objects[nr_dispatched].type))
1091                         nr_dispatched++;
1092                 if (nr_dispatched >= nr_objects) {
1093                         work_unlock();
1094                         break;
1095                 }
1096                 i = nr_dispatched++;
1097                 work_unlock();
1098
1099                 resolve_base(&objects[i]);
1100         }
1101         return NULL;
1102 }
1103 #endif
1104
1105 /*
1106  * First pass:
1107  * - find locations of all objects;
1108  * - calculate SHA1 of all non-delta objects;
1109  * - remember base (SHA1 or offset) for all deltas.
1110  */
1111 static void parse_pack_objects(unsigned char *sha1)
1112 {
1113         int i, nr_delays = 0;
1114         struct ofs_delta_entry *ofs_delta = ofs_deltas;
1115         unsigned char ref_delta_sha1[20];
1116         struct stat st;
1117
1118         if (verbose)
1119                 progress = start_progress(
1120                                 from_stdin ? _("Receiving objects") : _("Indexing objects"),
1121                                 nr_objects);
1122         for (i = 0; i < nr_objects; i++) {
1123                 struct object_entry *obj = &objects[i];
1124                 void *data = unpack_raw_entry(obj, &ofs_delta->offset,
1125                                               ref_delta_sha1, obj->idx.sha1);
1126                 obj->real_type = obj->type;
1127                 if (obj->type == OBJ_OFS_DELTA) {
1128                         nr_ofs_deltas++;
1129                         ofs_delta->obj_no = i;
1130                         ofs_delta++;
1131                 } else if (obj->type == OBJ_REF_DELTA) {
1132                         ALLOC_GROW(ref_deltas, nr_ref_deltas + 1, ref_deltas_alloc);
1133                         hashcpy(ref_deltas[nr_ref_deltas].sha1, ref_delta_sha1);
1134                         ref_deltas[nr_ref_deltas].obj_no = i;
1135                         nr_ref_deltas++;
1136                 } else if (!data) {
1137                         /* large blobs, check later */
1138                         obj->real_type = OBJ_BAD;
1139                         nr_delays++;
1140                 } else
1141                         sha1_object(data, NULL, obj->size, obj->type, obj->idx.sha1);
1142                 free(data);
1143                 display_progress(progress, i+1);
1144         }
1145         objects[i].idx.offset = consumed_bytes;
1146         stop_progress(&progress);
1147
1148         /* Check pack integrity */
1149         flush();
1150         git_SHA1_Final(sha1, &input_ctx);
1151         if (hashcmp(fill(20), sha1))
1152                 die(_("pack is corrupted (SHA1 mismatch)"));
1153         use(20);
1154
1155         /* If input_fd is a file, we should have reached its end now. */
1156         if (fstat(input_fd, &st))
1157                 die_errno(_("cannot fstat packfile"));
1158         if (S_ISREG(st.st_mode) &&
1159                         lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
1160                 die(_("pack has junk at the end"));
1161
1162         for (i = 0; i < nr_objects; i++) {
1163                 struct object_entry *obj = &objects[i];
1164                 if (obj->real_type != OBJ_BAD)
1165                         continue;
1166                 obj->real_type = obj->type;
1167                 sha1_object(NULL, obj, obj->size, obj->type, obj->idx.sha1);
1168                 nr_delays--;
1169         }
1170         if (nr_delays)
1171                 die(_("confusion beyond insanity in parse_pack_objects()"));
1172 }
1173
1174 /*
1175  * Second pass:
1176  * - for all non-delta objects, look if it is used as a base for
1177  *   deltas;
1178  * - if used as a base, uncompress the object and apply all deltas,
1179  *   recursively checking if the resulting object is used as a base
1180  *   for some more deltas.
1181  */
1182 static void resolve_deltas(void)
1183 {
1184         int i;
1185
1186         if (!nr_ofs_deltas && !nr_ref_deltas)
1187                 return;
1188
1189         /* Sort deltas by base SHA1/offset for fast searching */
1190         qsort(ofs_deltas, nr_ofs_deltas, sizeof(struct ofs_delta_entry),
1191               compare_ofs_delta_entry);
1192         qsort(ref_deltas, nr_ref_deltas, sizeof(struct ref_delta_entry),
1193               compare_ref_delta_entry);
1194
1195         if (verbose || show_resolving_progress)
1196                 progress = start_progress(_("Resolving deltas"),
1197                                           nr_ref_deltas + nr_ofs_deltas);
1198
1199 #ifndef NO_PTHREADS
1200         nr_dispatched = 0;
1201         if (nr_threads > 1 || getenv("GIT_FORCE_THREADS")) {
1202                 init_thread();
1203                 for (i = 0; i < nr_threads; i++) {
1204                         int ret = pthread_create(&thread_data[i].thread, NULL,
1205                                                  threaded_second_pass, thread_data + i);
1206                         if (ret)
1207                                 die(_("unable to create thread: %s"),
1208                                     strerror(ret));
1209                 }
1210                 for (i = 0; i < nr_threads; i++)
1211                         pthread_join(thread_data[i].thread, NULL);
1212                 cleanup_thread();
1213                 return;
1214         }
1215 #endif
1216
1217         for (i = 0; i < nr_objects; i++) {
1218                 struct object_entry *obj = &objects[i];
1219
1220                 if (is_delta_type(obj->type))
1221                         continue;
1222                 resolve_base(obj);
1223                 display_progress(progress, nr_resolved_deltas);
1224         }
1225 }
1226
1227 /*
1228  * Third pass:
1229  * - append objects to convert thin pack to full pack if required
1230  * - write the final 20-byte SHA-1
1231  */
1232 static void fix_unresolved_deltas(struct sha1file *f);
1233 static void conclude_pack(int fix_thin_pack, const char *curr_pack, unsigned char *pack_sha1)
1234 {
1235         if (nr_ref_deltas + nr_ofs_deltas == nr_resolved_deltas) {
1236                 stop_progress(&progress);
1237                 /* Flush remaining pack final 20-byte SHA1. */
1238                 flush();
1239                 return;
1240         }
1241
1242         if (fix_thin_pack) {
1243                 struct sha1file *f;
1244                 unsigned char read_sha1[20], tail_sha1[20];
1245                 struct strbuf msg = STRBUF_INIT;
1246                 int nr_unresolved = nr_ofs_deltas + nr_ref_deltas - nr_resolved_deltas;
1247                 int nr_objects_initial = nr_objects;
1248                 if (nr_unresolved <= 0)
1249                         die(_("confusion beyond insanity"));
1250                 REALLOC_ARRAY(objects, nr_objects + nr_unresolved + 1);
1251                 memset(objects + nr_objects + 1, 0,
1252                        nr_unresolved * sizeof(*objects));
1253                 f = sha1fd(output_fd, curr_pack);
1254                 fix_unresolved_deltas(f);
1255                 strbuf_addf(&msg, Q_("completed with %d local object",
1256                                      "completed with %d local objects",
1257                                      nr_objects - nr_objects_initial),
1258                             nr_objects - nr_objects_initial);
1259                 stop_progress_msg(&progress, msg.buf);
1260                 strbuf_release(&msg);
1261                 sha1close(f, tail_sha1, 0);
1262                 hashcpy(read_sha1, pack_sha1);
1263                 fixup_pack_header_footer(output_fd, pack_sha1,
1264                                          curr_pack, nr_objects,
1265                                          read_sha1, consumed_bytes-20);
1266                 if (hashcmp(read_sha1, tail_sha1) != 0)
1267                         die(_("Unexpected tail checksum for %s "
1268                               "(disk corruption?)"), curr_pack);
1269         }
1270         if (nr_ofs_deltas + nr_ref_deltas != nr_resolved_deltas)
1271                 die(Q_("pack has %d unresolved delta",
1272                        "pack has %d unresolved deltas",
1273                        nr_ofs_deltas + nr_ref_deltas - nr_resolved_deltas),
1274                     nr_ofs_deltas + nr_ref_deltas - nr_resolved_deltas);
1275 }
1276
1277 static int write_compressed(struct sha1file *f, void *in, unsigned int size)
1278 {
1279         git_zstream stream;
1280         int status;
1281         unsigned char outbuf[4096];
1282
1283         git_deflate_init(&stream, zlib_compression_level);
1284         stream.next_in = in;
1285         stream.avail_in = size;
1286
1287         do {
1288                 stream.next_out = outbuf;
1289                 stream.avail_out = sizeof(outbuf);
1290                 status = git_deflate(&stream, Z_FINISH);
1291                 sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
1292         } while (status == Z_OK);
1293
1294         if (status != Z_STREAM_END)
1295                 die(_("unable to deflate appended object (%d)"), status);
1296         size = stream.total_out;
1297         git_deflate_end(&stream);
1298         return size;
1299 }
1300
1301 static struct object_entry *append_obj_to_pack(struct sha1file *f,
1302                                const unsigned char *sha1, void *buf,
1303                                unsigned long size, enum object_type type)
1304 {
1305         struct object_entry *obj = &objects[nr_objects++];
1306         unsigned char header[10];
1307         unsigned long s = size;
1308         int n = 0;
1309         unsigned char c = (type << 4) | (s & 15);
1310         s >>= 4;
1311         while (s) {
1312                 header[n++] = c | 0x80;
1313                 c = s & 0x7f;
1314                 s >>= 7;
1315         }
1316         header[n++] = c;
1317         crc32_begin(f);
1318         sha1write(f, header, n);
1319         obj[0].size = size;
1320         obj[0].hdr_size = n;
1321         obj[0].type = type;
1322         obj[0].real_type = type;
1323         obj[1].idx.offset = obj[0].idx.offset + n;
1324         obj[1].idx.offset += write_compressed(f, buf, size);
1325         obj[0].idx.crc32 = crc32_end(f);
1326         sha1flush(f);
1327         hashcpy(obj->idx.sha1, sha1);
1328         return obj;
1329 }
1330
1331 static int delta_pos_compare(const void *_a, const void *_b)
1332 {
1333         struct ref_delta_entry *a = *(struct ref_delta_entry **)_a;
1334         struct ref_delta_entry *b = *(struct ref_delta_entry **)_b;
1335         return a->obj_no - b->obj_no;
1336 }
1337
1338 static void fix_unresolved_deltas(struct sha1file *f)
1339 {
1340         struct ref_delta_entry **sorted_by_pos;
1341         int i;
1342
1343         /*
1344          * Since many unresolved deltas may well be themselves base objects
1345          * for more unresolved deltas, we really want to include the
1346          * smallest number of base objects that would cover as much delta
1347          * as possible by picking the
1348          * trunc deltas first, allowing for other deltas to resolve without
1349          * additional base objects.  Since most base objects are to be found
1350          * before deltas depending on them, a good heuristic is to start
1351          * resolving deltas in the same order as their position in the pack.
1352          */
1353         ALLOC_ARRAY(sorted_by_pos, nr_ref_deltas);
1354         for (i = 0; i < nr_ref_deltas; i++)
1355                 sorted_by_pos[i] = &ref_deltas[i];
1356         qsort(sorted_by_pos, nr_ref_deltas, sizeof(*sorted_by_pos), delta_pos_compare);
1357
1358         for (i = 0; i < nr_ref_deltas; i++) {
1359                 struct ref_delta_entry *d = sorted_by_pos[i];
1360                 enum object_type type;
1361                 struct base_data *base_obj = alloc_base_data();
1362
1363                 if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
1364                         continue;
1365                 base_obj->data = read_sha1_file(d->sha1, &type, &base_obj->size);
1366                 if (!base_obj->data)
1367                         continue;
1368
1369                 if (check_sha1_signature(d->sha1, base_obj->data,
1370                                 base_obj->size, typename(type)))
1371                         die(_("local object %s is corrupt"), sha1_to_hex(d->sha1));
1372                 base_obj->obj = append_obj_to_pack(f, d->sha1,
1373                                         base_obj->data, base_obj->size, type);
1374                 find_unresolved_deltas(base_obj);
1375                 display_progress(progress, nr_resolved_deltas);
1376         }
1377         free(sorted_by_pos);
1378 }
1379
1380 static void final(const char *final_pack_name, const char *curr_pack_name,
1381                   const char *final_index_name, const char *curr_index_name,
1382                   const char *keep_name, const char *keep_msg,
1383                   unsigned char *sha1)
1384 {
1385         const char *report = "pack";
1386         char name[PATH_MAX];
1387         int err;
1388
1389         if (!from_stdin) {
1390                 close(input_fd);
1391         } else {
1392                 fsync_or_die(output_fd, curr_pack_name);
1393                 err = close(output_fd);
1394                 if (err)
1395                         die_errno(_("error while closing pack file"));
1396         }
1397
1398         if (keep_msg) {
1399                 int keep_fd, keep_msg_len = strlen(keep_msg);
1400
1401                 if (!keep_name)
1402                         keep_fd = odb_pack_keep(name, sizeof(name), sha1);
1403                 else
1404                         keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
1405
1406                 if (keep_fd < 0) {
1407                         if (errno != EEXIST)
1408                                 die_errno(_("cannot write keep file '%s'"),
1409                                           keep_name ? keep_name : name);
1410                 } else {
1411                         if (keep_msg_len > 0) {
1412                                 write_or_die(keep_fd, keep_msg, keep_msg_len);
1413                                 write_or_die(keep_fd, "\n", 1);
1414                         }
1415                         if (close(keep_fd) != 0)
1416                                 die_errno(_("cannot close written keep file '%s'"),
1417                                           keep_name ? keep_name : name);
1418                         report = "keep";
1419                 }
1420         }
1421
1422         if (final_pack_name != curr_pack_name) {
1423                 if (!final_pack_name) {
1424                         snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
1425                                  get_object_directory(), sha1_to_hex(sha1));
1426                         final_pack_name = name;
1427                 }
1428                 if (finalize_object_file(curr_pack_name, final_pack_name))
1429                         die(_("cannot store pack file"));
1430         } else if (from_stdin)
1431                 chmod(final_pack_name, 0444);
1432
1433         if (final_index_name != curr_index_name) {
1434                 if (!final_index_name) {
1435                         snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
1436                                  get_object_directory(), sha1_to_hex(sha1));
1437                         final_index_name = name;
1438                 }
1439                 if (finalize_object_file(curr_index_name, final_index_name))
1440                         die(_("cannot store index file"));
1441         } else
1442                 chmod(final_index_name, 0444);
1443
1444         if (!from_stdin) {
1445                 printf("%s\n", sha1_to_hex(sha1));
1446         } else {
1447                 char buf[48];
1448                 int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
1449                                    report, sha1_to_hex(sha1));
1450                 write_or_die(1, buf, len);
1451
1452                 /*
1453                  * Let's just mimic git-unpack-objects here and write
1454                  * the last part of the input buffer to stdout.
1455                  */
1456                 while (input_len) {
1457                         err = xwrite(1, input_buffer + input_offset, input_len);
1458                         if (err <= 0)
1459                                 break;
1460                         input_len -= err;
1461                         input_offset += err;
1462                 }
1463         }
1464 }
1465
1466 static int git_index_pack_config(const char *k, const char *v, void *cb)
1467 {
1468         struct pack_idx_option *opts = cb;
1469
1470         if (!strcmp(k, "pack.indexversion")) {
1471                 opts->version = git_config_int(k, v);
1472                 if (opts->version > 2)
1473                         die(_("bad pack.indexversion=%"PRIu32), opts->version);
1474                 return 0;
1475         }
1476         if (!strcmp(k, "pack.threads")) {
1477                 nr_threads = git_config_int(k, v);
1478                 if (nr_threads < 0)
1479                         die(_("invalid number of threads specified (%d)"),
1480                             nr_threads);
1481 #ifdef NO_PTHREADS
1482                 if (nr_threads != 1)
1483                         warning(_("no threads support, ignoring %s"), k);
1484                 nr_threads = 1;
1485 #endif
1486                 return 0;
1487         }
1488         return git_default_config(k, v, cb);
1489 }
1490
1491 static int cmp_uint32(const void *a_, const void *b_)
1492 {
1493         uint32_t a = *((uint32_t *)a_);
1494         uint32_t b = *((uint32_t *)b_);
1495
1496         return (a < b) ? -1 : (a != b);
1497 }
1498
1499 static void read_v2_anomalous_offsets(struct packed_git *p,
1500                                       struct pack_idx_option *opts)
1501 {
1502         const uint32_t *idx1, *idx2;
1503         uint32_t i;
1504
1505         /* The address of the 4-byte offset table */
1506         idx1 = (((const uint32_t *)p->index_data)
1507                 + 2 /* 8-byte header */
1508                 + 256 /* fan out */
1509                 + 5 * p->num_objects /* 20-byte SHA-1 table */
1510                 + p->num_objects /* CRC32 table */
1511                 );
1512
1513         /* The address of the 8-byte offset table */
1514         idx2 = idx1 + p->num_objects;
1515
1516         for (i = 0; i < p->num_objects; i++) {
1517                 uint32_t off = ntohl(idx1[i]);
1518                 if (!(off & 0x80000000))
1519                         continue;
1520                 off = off & 0x7fffffff;
1521                 check_pack_index_ptr(p, &idx2[off * 2]);
1522                 if (idx2[off * 2])
1523                         continue;
1524                 /*
1525                  * The real offset is ntohl(idx2[off * 2]) in high 4
1526                  * octets, and ntohl(idx2[off * 2 + 1]) in low 4
1527                  * octets.  But idx2[off * 2] is Zero!!!
1528                  */
1529                 ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc);
1530                 opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]);
1531         }
1532
1533         if (1 < opts->anomaly_nr)
1534                 qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32);
1535 }
1536
1537 static void read_idx_option(struct pack_idx_option *opts, const char *pack_name)
1538 {
1539         struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1);
1540
1541         if (!p)
1542                 die(_("Cannot open existing pack file '%s'"), pack_name);
1543         if (open_pack_index(p))
1544                 die(_("Cannot open existing pack idx file for '%s'"), pack_name);
1545
1546         /* Read the attributes from the existing idx file */
1547         opts->version = p->index_version;
1548
1549         if (opts->version == 2)
1550                 read_v2_anomalous_offsets(p, opts);
1551
1552         /*
1553          * Get rid of the idx file as we do not need it anymore.
1554          * NEEDSWORK: extract this bit from free_pack_by_name() in
1555          * sha1_file.c, perhaps?  It shouldn't matter very much as we
1556          * know we haven't installed this pack (hence we never have
1557          * read anything from it).
1558          */
1559         close_pack_index(p);
1560         free(p);
1561 }
1562
1563 static void show_pack_info(int stat_only)
1564 {
1565         int i, baseobjects = nr_objects - nr_ref_deltas - nr_ofs_deltas;
1566         unsigned long *chain_histogram = NULL;
1567
1568         if (deepest_delta)
1569                 chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long));
1570
1571         for (i = 0; i < nr_objects; i++) {
1572                 struct object_entry *obj = &objects[i];
1573
1574                 if (is_delta_type(obj->type))
1575                         chain_histogram[obj_stat[i].delta_depth - 1]++;
1576                 if (stat_only)
1577                         continue;
1578                 printf("%s %-6s %lu %lu %"PRIuMAX,
1579                        sha1_to_hex(obj->idx.sha1),
1580                        typename(obj->real_type), obj->size,
1581                        (unsigned long)(obj[1].idx.offset - obj->idx.offset),
1582                        (uintmax_t)obj->idx.offset);
1583                 if (is_delta_type(obj->type)) {
1584                         struct object_entry *bobj = &objects[obj_stat[i].base_object_no];
1585                         printf(" %u %s", obj_stat[i].delta_depth, sha1_to_hex(bobj->idx.sha1));
1586                 }
1587                 putchar('\n');
1588         }
1589
1590         if (baseobjects)
1591                 printf_ln(Q_("non delta: %d object",
1592                              "non delta: %d objects",
1593                              baseobjects),
1594                           baseobjects);
1595         for (i = 0; i < deepest_delta; i++) {
1596                 if (!chain_histogram[i])
1597                         continue;
1598                 printf_ln(Q_("chain length = %d: %lu object",
1599                              "chain length = %d: %lu objects",
1600                              chain_histogram[i]),
1601                           i + 1,
1602                           chain_histogram[i]);
1603         }
1604 }
1605
1606 static const char *derive_filename(const char *pack_name, const char *suffix,
1607                                    struct strbuf *buf)
1608 {
1609         size_t len;
1610         if (!strip_suffix(pack_name, ".pack", &len))
1611                 die(_("packfile name '%s' does not end with '.pack'"),
1612                     pack_name);
1613         strbuf_add(buf, pack_name, len);
1614         strbuf_addstr(buf, suffix);
1615         return buf->buf;
1616 }
1617
1618 int cmd_index_pack(int argc, const char **argv, const char *prefix)
1619 {
1620         int i, fix_thin_pack = 0, verify = 0, stat_only = 0;
1621         const char *curr_index;
1622         const char *index_name = NULL, *pack_name = NULL;
1623         const char *keep_name = NULL, *keep_msg = NULL;
1624         struct strbuf index_name_buf = STRBUF_INIT,
1625                       keep_name_buf = STRBUF_INIT;
1626         struct pack_idx_entry **idx_objects;
1627         struct pack_idx_option opts;
1628         unsigned char pack_sha1[20];
1629         unsigned foreign_nr = 1;        /* zero is a "good" value, assume bad */
1630         int report_end_of_input = 0;
1631
1632         if (argc == 2 && !strcmp(argv[1], "-h"))
1633                 usage(index_pack_usage);
1634
1635         check_replace_refs = 0;
1636         fsck_options.walk = mark_link;
1637
1638         reset_pack_idx_option(&opts);
1639         git_config(git_index_pack_config, &opts);
1640         if (prefix && chdir(prefix))
1641                 die(_("Cannot come back to cwd"));
1642
1643         for (i = 1; i < argc; i++) {
1644                 const char *arg = argv[i];
1645
1646                 if (*arg == '-') {
1647                         if (!strcmp(arg, "--stdin")) {
1648                                 from_stdin = 1;
1649                         } else if (!strcmp(arg, "--fix-thin")) {
1650                                 fix_thin_pack = 1;
1651                         } else if (!strcmp(arg, "--strict")) {
1652                                 strict = 1;
1653                                 do_fsck_object = 1;
1654                         } else if (skip_prefix(arg, "--strict=", &arg)) {
1655                                 strict = 1;
1656                                 do_fsck_object = 1;
1657                                 fsck_set_msg_types(&fsck_options, arg);
1658                         } else if (!strcmp(arg, "--check-self-contained-and-connected")) {
1659                                 strict = 1;
1660                                 check_self_contained_and_connected = 1;
1661                         } else if (!strcmp(arg, "--verify")) {
1662                                 verify = 1;
1663                         } else if (!strcmp(arg, "--verify-stat")) {
1664                                 verify = 1;
1665                                 show_stat = 1;
1666                         } else if (!strcmp(arg, "--verify-stat-only")) {
1667                                 verify = 1;
1668                                 show_stat = 1;
1669                                 stat_only = 1;
1670                         } else if (!strcmp(arg, "--keep")) {
1671                                 keep_msg = "";
1672                         } else if (starts_with(arg, "--keep=")) {
1673                                 keep_msg = arg + 7;
1674                         } else if (starts_with(arg, "--threads=")) {
1675                                 char *end;
1676                                 nr_threads = strtoul(arg+10, &end, 0);
1677                                 if (!arg[10] || *end || nr_threads < 0)
1678                                         usage(index_pack_usage);
1679 #ifdef NO_PTHREADS
1680                                 if (nr_threads != 1)
1681                                         warning(_("no threads support, "
1682                                                   "ignoring %s"), arg);
1683                                 nr_threads = 1;
1684 #endif
1685                         } else if (starts_with(arg, "--pack_header=")) {
1686                                 struct pack_header *hdr;
1687                                 char *c;
1688
1689                                 hdr = (struct pack_header *)input_buffer;
1690                                 hdr->hdr_signature = htonl(PACK_SIGNATURE);
1691                                 hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
1692                                 if (*c != ',')
1693                                         die(_("bad %s"), arg);
1694                                 hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
1695                                 if (*c)
1696                                         die(_("bad %s"), arg);
1697                                 input_len = sizeof(*hdr);
1698                         } else if (!strcmp(arg, "-v")) {
1699                                 verbose = 1;
1700                         } else if (!strcmp(arg, "--show-resolving-progress")) {
1701                                 show_resolving_progress = 1;
1702                         } else if (!strcmp(arg, "--report-end-of-input")) {
1703                                 report_end_of_input = 1;
1704                         } else if (!strcmp(arg, "-o")) {
1705                                 if (index_name || (i+1) >= argc)
1706                                         usage(index_pack_usage);
1707                                 index_name = argv[++i];
1708                         } else if (starts_with(arg, "--index-version=")) {
1709                                 char *c;
1710                                 opts.version = strtoul(arg + 16, &c, 10);
1711                                 if (opts.version > 2)
1712                                         die(_("bad %s"), arg);
1713                                 if (*c == ',')
1714                                         opts.off32_limit = strtoul(c+1, &c, 0);
1715                                 if (*c || opts.off32_limit & 0x80000000)
1716                                         die(_("bad %s"), arg);
1717                         } else
1718                                 usage(index_pack_usage);
1719                         continue;
1720                 }
1721
1722                 if (pack_name)
1723                         usage(index_pack_usage);
1724                 pack_name = arg;
1725         }
1726
1727         if (!pack_name && !from_stdin)
1728                 usage(index_pack_usage);
1729         if (fix_thin_pack && !from_stdin)
1730                 die(_("--fix-thin cannot be used without --stdin"));
1731         if (!index_name && pack_name)
1732                 index_name = derive_filename(pack_name, ".idx", &index_name_buf);
1733         if (keep_msg && !keep_name && pack_name)
1734                 keep_name = derive_filename(pack_name, ".keep", &keep_name_buf);
1735
1736         if (verify) {
1737                 if (!index_name)
1738                         die(_("--verify with no packfile name given"));
1739                 read_idx_option(&opts, index_name);
1740                 opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
1741         }
1742         if (strict)
1743                 opts.flags |= WRITE_IDX_STRICT;
1744
1745 #ifndef NO_PTHREADS
1746         if (!nr_threads) {
1747                 nr_threads = online_cpus();
1748                 /* An experiment showed that more threads does not mean faster */
1749                 if (nr_threads > 3)
1750                         nr_threads = 3;
1751         }
1752 #endif
1753
1754         curr_pack = open_pack_file(pack_name);
1755         parse_pack_header();
1756         objects = xcalloc(st_add(nr_objects, 1), sizeof(struct object_entry));
1757         if (show_stat)
1758                 obj_stat = xcalloc(st_add(nr_objects, 1), sizeof(struct object_stat));
1759         ofs_deltas = xcalloc(nr_objects, sizeof(struct ofs_delta_entry));
1760         parse_pack_objects(pack_sha1);
1761         if (report_end_of_input)
1762                 write_in_full(2, "\0", 1);
1763         resolve_deltas();
1764         conclude_pack(fix_thin_pack, curr_pack, pack_sha1);
1765         free(ofs_deltas);
1766         free(ref_deltas);
1767         if (strict)
1768                 foreign_nr = check_objects();
1769
1770         if (show_stat)
1771                 show_pack_info(stat_only);
1772
1773         ALLOC_ARRAY(idx_objects, nr_objects);
1774         for (i = 0; i < nr_objects; i++)
1775                 idx_objects[i] = &objects[i].idx;
1776         curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1);
1777         free(idx_objects);
1778
1779         if (!verify)
1780                 final(pack_name, curr_pack,
1781                       index_name, curr_index,
1782                       keep_name, keep_msg,
1783                       pack_sha1);
1784         else
1785                 close(input_fd);
1786         free(objects);
1787         strbuf_release(&index_name_buf);
1788         strbuf_release(&keep_name_buf);
1789         if (pack_name == NULL)
1790                 free((void *) curr_pack);
1791         if (index_name == NULL)
1792                 free((void *) curr_index);
1793
1794         /*
1795          * Let the caller know this pack is not self contained
1796          */
1797         if (check_self_contained_and_connected && foreign_nr)
1798                 return 1;
1799
1800         return 0;
1801 }