Code

59ae64d83ff8ef28130384d4d6476ffd8a7715ad
[git.git] / builtin-pack-objects.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "attr.h"
4 #include "object.h"
5 #include "blob.h"
6 #include "commit.h"
7 #include "tag.h"
8 #include "tree.h"
9 #include "delta.h"
10 #include "pack.h"
11 #include "pack-revindex.h"
12 #include "csum-file.h"
13 #include "tree-walk.h"
14 #include "diff.h"
15 #include "revision.h"
16 #include "list-objects.h"
17 #include "progress.h"
18 #include "refs.h"
20 #ifdef THREADED_DELTA_SEARCH
21 #include "thread-utils.h"
22 #include <pthread.h>
23 #endif
25 static const char pack_usage[] = "\
26 git pack-objects [{ -q | --progress | --all-progress }] \n\
27         [--max-pack-size=N] [--local] [--incremental] \n\
28         [--window=N] [--window-memory=N] [--depth=N] \n\
29         [--no-reuse-delta] [--no-reuse-object] [--delta-base-offset] \n\
30         [--threads=N] [--non-empty] [--revs [--unpacked | --all]*] [--reflog] \n\
31         [--stdout | base-name] [--include-tag] \n\
32         [--keep-unreachable | --unpack-unreachable] \n\
33         [<ref-list | <object-list]";
35 struct object_entry {
36         struct pack_idx_entry idx;
37         unsigned long size;     /* uncompressed size */
38         struct packed_git *in_pack;     /* already in pack */
39         off_t in_pack_offset;
40         struct object_entry *delta;     /* delta base object */
41         struct object_entry *delta_child; /* deltified objects who bases me */
42         struct object_entry *delta_sibling; /* other deltified objects who
43                                              * uses the same base as me
44                                              */
45         void *delta_data;       /* cached delta (uncompressed) */
46         unsigned long delta_size;       /* delta data size (uncompressed) */
47         unsigned long z_delta_size;     /* delta data size (compressed) */
48         unsigned int hash;      /* name hint hash */
49         enum object_type type;
50         enum object_type in_pack_type;  /* could be delta */
51         unsigned char in_pack_header_size;
52         unsigned char preferred_base; /* we do not pack this, but is available
53                                        * to be used as the base object to delta
54                                        * objects against.
55                                        */
56         unsigned char no_try_delta;
57 };
59 /*
60  * Objects we are going to pack are collected in objects array (dynamically
61  * expanded).  nr_objects & nr_alloc controls this array.  They are stored
62  * in the order we see -- typically rev-list --objects order that gives us
63  * nice "minimum seek" order.
64  */
65 static struct object_entry *objects;
66 static struct pack_idx_entry **written_list;
67 static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
69 static int non_empty;
70 static int reuse_delta = 1, reuse_object = 1;
71 static int keep_unreachable, unpack_unreachable, include_tag;
72 static int local;
73 static int incremental;
74 static int ignore_packed_keep;
75 static int allow_ofs_delta;
76 static const char *base_name;
77 static int progress = 1;
78 static int window = 10;
79 static uint32_t pack_size_limit, pack_size_limit_cfg;
80 static int depth = 50;
81 static int delta_search_threads = 1;
82 static int pack_to_stdout;
83 static int num_preferred_base;
84 static struct progress *progress_state;
85 static int pack_compression_level = Z_DEFAULT_COMPRESSION;
86 static int pack_compression_seen;
88 static unsigned long delta_cache_size = 0;
89 static unsigned long max_delta_cache_size = 0;
90 static unsigned long cache_max_small_delta_size = 1000;
92 static unsigned long window_memory_limit = 0;
94 /*
95  * The object names in objects array are hashed with this hashtable,
96  * to help looking up the entry by object name.
97  * This hashtable is built after all the objects are seen.
98  */
99 static int *object_ix;
100 static int object_ix_hashsz;
102 /*
103  * stats
104  */
105 static uint32_t written, written_delta;
106 static uint32_t reused, reused_delta;
109 static void *get_delta(struct object_entry *entry)
111         unsigned long size, base_size, delta_size;
112         void *buf, *base_buf, *delta_buf;
113         enum object_type type;
115         buf = read_sha1_file(entry->idx.sha1, &type, &size);
116         if (!buf)
117                 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
118         base_buf = read_sha1_file(entry->delta->idx.sha1, &type, &base_size);
119         if (!base_buf)
120                 die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
121         delta_buf = diff_delta(base_buf, base_size,
122                                buf, size, &delta_size, 0);
123         if (!delta_buf || delta_size != entry->delta_size)
124                 die("delta size changed");
125         free(buf);
126         free(base_buf);
127         return delta_buf;
130 static unsigned long do_compress(void **pptr, unsigned long size)
132         z_stream stream;
133         void *in, *out;
134         unsigned long maxsize;
136         memset(&stream, 0, sizeof(stream));
137         deflateInit(&stream, pack_compression_level);
138         maxsize = deflateBound(&stream, size);
140         in = *pptr;
141         out = xmalloc(maxsize);
142         *pptr = out;
144         stream.next_in = in;
145         stream.avail_in = size;
146         stream.next_out = out;
147         stream.avail_out = maxsize;
148         while (deflate(&stream, Z_FINISH) == Z_OK)
149                 ; /* nothing */
150         deflateEnd(&stream);
152         free(in);
153         return stream.total_out;
156 /*
157  * The per-object header is a pretty dense thing, which is
158  *  - first byte: low four bits are "size", then three bits of "type",
159  *    and the high bit is "size continues".
160  *  - each byte afterwards: low seven bits are size continuation,
161  *    with the high bit being "size continues"
162  */
163 static int encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
165         int n = 1;
166         unsigned char c;
168         if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
169                 die("bad type %d", type);
171         c = (type << 4) | (size & 15);
172         size >>= 4;
173         while (size) {
174                 *hdr++ = c | 0x80;
175                 c = size & 0x7f;
176                 size >>= 7;
177                 n++;
178         }
179         *hdr = c;
180         return n;
183 /*
184  * we are going to reuse the existing object data as is.  make
185  * sure it is not corrupt.
186  */
187 static int check_pack_inflate(struct packed_git *p,
188                 struct pack_window **w_curs,
189                 off_t offset,
190                 off_t len,
191                 unsigned long expect)
193         z_stream stream;
194         unsigned char fakebuf[4096], *in;
195         int st;
197         memset(&stream, 0, sizeof(stream));
198         inflateInit(&stream);
199         do {
200                 in = use_pack(p, w_curs, offset, &stream.avail_in);
201                 stream.next_in = in;
202                 stream.next_out = fakebuf;
203                 stream.avail_out = sizeof(fakebuf);
204                 st = inflate(&stream, Z_FINISH);
205                 offset += stream.next_in - in;
206         } while (st == Z_OK || st == Z_BUF_ERROR);
207         inflateEnd(&stream);
208         return (st == Z_STREAM_END &&
209                 stream.total_out == expect &&
210                 stream.total_in == len) ? 0 : -1;
213 static void copy_pack_data(struct sha1file *f,
214                 struct packed_git *p,
215                 struct pack_window **w_curs,
216                 off_t offset,
217                 off_t len)
219         unsigned char *in;
220         unsigned int avail;
222         while (len) {
223                 in = use_pack(p, w_curs, offset, &avail);
224                 if (avail > len)
225                         avail = (unsigned int)len;
226                 sha1write(f, in, avail);
227                 offset += avail;
228                 len -= avail;
229         }
232 static unsigned long write_object(struct sha1file *f,
233                                   struct object_entry *entry,
234                                   off_t write_offset)
236         unsigned long size, limit, datalen;
237         void *buf;
238         unsigned char header[10], dheader[10];
239         unsigned hdrlen;
240         enum object_type type;
241         int usable_delta, to_reuse;
243         if (!pack_to_stdout)
244                 crc32_begin(f);
246         type = entry->type;
248         /* write limit if limited packsize and not first object */
249         if (!pack_size_limit || !nr_written)
250                 limit = 0;
251         else if (pack_size_limit <= write_offset)
252                 /*
253                  * the earlier object did not fit the limit; avoid
254                  * mistaking this with unlimited (i.e. limit = 0).
255                  */
256                 limit = 1;
257         else
258                 limit = pack_size_limit - write_offset;
260         if (!entry->delta)
261                 usable_delta = 0;       /* no delta */
262         else if (!pack_size_limit)
263                usable_delta = 1;        /* unlimited packfile */
264         else if (entry->delta->idx.offset == (off_t)-1)
265                 usable_delta = 0;       /* base was written to another pack */
266         else if (entry->delta->idx.offset)
267                 usable_delta = 1;       /* base already exists in this pack */
268         else
269                 usable_delta = 0;       /* base could end up in another pack */
271         if (!reuse_object)
272                 to_reuse = 0;   /* explicit */
273         else if (!entry->in_pack)
274                 to_reuse = 0;   /* can't reuse what we don't have */
275         else if (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA)
276                                 /* check_object() decided it for us ... */
277                 to_reuse = usable_delta;
278                                 /* ... but pack split may override that */
279         else if (type != entry->in_pack_type)
280                 to_reuse = 0;   /* pack has delta which is unusable */
281         else if (entry->delta)
282                 to_reuse = 0;   /* we want to pack afresh */
283         else
284                 to_reuse = 1;   /* we have it in-pack undeltified,
285                                  * and we do not need to deltify it.
286                                  */
288         if (!to_reuse) {
289                 if (!usable_delta) {
290                         buf = read_sha1_file(entry->idx.sha1, &type, &size);
291                         if (!buf)
292                                 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
293                         /*
294                          * make sure no cached delta data remains from a
295                          * previous attempt before a pack split occured.
296                          */
297                         free(entry->delta_data);
298                         entry->delta_data = NULL;
299                         entry->z_delta_size = 0;
300                 } else if (entry->delta_data) {
301                         size = entry->delta_size;
302                         buf = entry->delta_data;
303                         entry->delta_data = NULL;
304                         type = (allow_ofs_delta && entry->delta->idx.offset) ?
305                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
306                 } else {
307                         buf = get_delta(entry);
308                         size = entry->delta_size;
309                         type = (allow_ofs_delta && entry->delta->idx.offset) ?
310                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
311                 }
313                 if (entry->z_delta_size)
314                         datalen = entry->z_delta_size;
315                 else
316                         datalen = do_compress(&buf, size);
318                 /*
319                  * The object header is a byte of 'type' followed by zero or
320                  * more bytes of length.
321                  */
322                 hdrlen = encode_header(type, size, header);
324                 if (type == OBJ_OFS_DELTA) {
325                         /*
326                          * Deltas with relative base contain an additional
327                          * encoding of the relative offset for the delta
328                          * base from this object's position in the pack.
329                          */
330                         off_t ofs = entry->idx.offset - entry->delta->idx.offset;
331                         unsigned pos = sizeof(dheader) - 1;
332                         dheader[pos] = ofs & 127;
333                         while (ofs >>= 7)
334                                 dheader[--pos] = 128 | (--ofs & 127);
335                         if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
336                                 free(buf);
337                                 return 0;
338                         }
339                         sha1write(f, header, hdrlen);
340                         sha1write(f, dheader + pos, sizeof(dheader) - pos);
341                         hdrlen += sizeof(dheader) - pos;
342                 } else if (type == OBJ_REF_DELTA) {
343                         /*
344                          * Deltas with a base reference contain
345                          * an additional 20 bytes for the base sha1.
346                          */
347                         if (limit && hdrlen + 20 + datalen + 20 >= limit) {
348                                 free(buf);
349                                 return 0;
350                         }
351                         sha1write(f, header, hdrlen);
352                         sha1write(f, entry->delta->idx.sha1, 20);
353                         hdrlen += 20;
354                 } else {
355                         if (limit && hdrlen + datalen + 20 >= limit) {
356                                 free(buf);
357                                 return 0;
358                         }
359                         sha1write(f, header, hdrlen);
360                 }
361                 sha1write(f, buf, datalen);
362                 free(buf);
363         }
364         else {
365                 struct packed_git *p = entry->in_pack;
366                 struct pack_window *w_curs = NULL;
367                 struct revindex_entry *revidx;
368                 off_t offset;
370                 if (entry->delta) {
371                         type = (allow_ofs_delta && entry->delta->idx.offset) ?
372                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
373                         reused_delta++;
374                 }
375                 hdrlen = encode_header(type, entry->size, header);
376                 offset = entry->in_pack_offset;
377                 revidx = find_pack_revindex(p, offset);
378                 datalen = revidx[1].offset - offset;
379                 if (!pack_to_stdout && p->index_version > 1 &&
380                     check_pack_crc(p, &w_curs, offset, datalen, revidx->nr))
381                         die("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
382                 offset += entry->in_pack_header_size;
383                 datalen -= entry->in_pack_header_size;
384                 if (type == OBJ_OFS_DELTA) {
385                         off_t ofs = entry->idx.offset - entry->delta->idx.offset;
386                         unsigned pos = sizeof(dheader) - 1;
387                         dheader[pos] = ofs & 127;
388                         while (ofs >>= 7)
389                                 dheader[--pos] = 128 | (--ofs & 127);
390                         if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit)
391                                 return 0;
392                         sha1write(f, header, hdrlen);
393                         sha1write(f, dheader + pos, sizeof(dheader) - pos);
394                         hdrlen += sizeof(dheader) - pos;
395                 } else if (type == OBJ_REF_DELTA) {
396                         if (limit && hdrlen + 20 + datalen + 20 >= limit)
397                                 return 0;
398                         sha1write(f, header, hdrlen);
399                         sha1write(f, entry->delta->idx.sha1, 20);
400                         hdrlen += 20;
401                 } else {
402                         if (limit && hdrlen + datalen + 20 >= limit)
403                                 return 0;
404                         sha1write(f, header, hdrlen);
405                 }
407                 if (!pack_to_stdout && p->index_version == 1 &&
408                     check_pack_inflate(p, &w_curs, offset, datalen, entry->size))
409                         die("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
410                 copy_pack_data(f, p, &w_curs, offset, datalen);
411                 unuse_pack(&w_curs);
412                 reused++;
413         }
414         if (usable_delta)
415                 written_delta++;
416         written++;
417         if (!pack_to_stdout)
418                 entry->idx.crc32 = crc32_end(f);
419         return hdrlen + datalen;
422 static int write_one(struct sha1file *f,
423                                struct object_entry *e,
424                                off_t *offset)
426         unsigned long size;
428         /* offset is non zero if object is written already. */
429         if (e->idx.offset || e->preferred_base)
430                 return 1;
432         /* if we are deltified, write out base object first. */
433         if (e->delta && !write_one(f, e->delta, offset))
434                 return 0;
436         e->idx.offset = *offset;
437         size = write_object(f, e, *offset);
438         if (!size) {
439                 e->idx.offset = 0;
440                 return 0;
441         }
442         written_list[nr_written++] = &e->idx;
444         /* make sure off_t is sufficiently large not to wrap */
445         if (*offset > *offset + size)
446                 die("pack too large for current definition of off_t");
447         *offset += size;
448         return 1;
451 /* forward declaration for write_pack_file */
452 static int adjust_perm(const char *path, mode_t mode);
454 static void write_pack_file(void)
456         uint32_t i = 0, j;
457         struct sha1file *f;
458         off_t offset;
459         struct pack_header hdr;
460         uint32_t nr_remaining = nr_result;
461         time_t last_mtime = 0;
463         if (progress > pack_to_stdout)
464                 progress_state = start_progress("Writing objects", nr_result);
465         written_list = xmalloc(nr_objects * sizeof(*written_list));
467         do {
468                 unsigned char sha1[20];
469                 char *pack_tmp_name = NULL;
471                 if (pack_to_stdout) {
472                         f = sha1fd_throughput(1, "<stdout>", progress_state);
473                 } else {
474                         char tmpname[PATH_MAX];
475                         int fd;
476                         snprintf(tmpname, sizeof(tmpname),
477                                  "%s/pack/tmp_pack_XXXXXX", get_object_directory());
478                         fd = xmkstemp(tmpname);
479                         pack_tmp_name = xstrdup(tmpname);
480                         f = sha1fd(fd, pack_tmp_name);
481                 }
483                 hdr.hdr_signature = htonl(PACK_SIGNATURE);
484                 hdr.hdr_version = htonl(PACK_VERSION);
485                 hdr.hdr_entries = htonl(nr_remaining);
486                 sha1write(f, &hdr, sizeof(hdr));
487                 offset = sizeof(hdr);
488                 nr_written = 0;
489                 for (; i < nr_objects; i++) {
490                         if (!write_one(f, objects + i, &offset))
491                                 break;
492                         display_progress(progress_state, written);
493                 }
495                 /*
496                  * Did we write the wrong # entries in the header?
497                  * If so, rewrite it like in fast-import
498                  */
499                 if (pack_to_stdout) {
500                         sha1close(f, sha1, CSUM_CLOSE);
501                 } else if (nr_written == nr_remaining) {
502                         sha1close(f, sha1, CSUM_FSYNC);
503                 } else {
504                         int fd = sha1close(f, sha1, 0);
505                         fixup_pack_header_footer(fd, sha1, pack_tmp_name,
506                                                  nr_written, sha1, offset);
507                         close(fd);
508                 }
510                 if (!pack_to_stdout) {
511                         mode_t mode = umask(0);
512                         struct stat st;
513                         char *idx_tmp_name, tmpname[PATH_MAX];
515                         umask(mode);
516                         mode = 0444 & ~mode;
518                         idx_tmp_name = write_idx_file(NULL, written_list,
519                                                       nr_written, sha1);
521                         snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
522                                  base_name, sha1_to_hex(sha1));
523                         if (adjust_perm(pack_tmp_name, mode))
524                                 die("unable to make temporary pack file readable: %s",
525                                     strerror(errno));
526                         if (rename(pack_tmp_name, tmpname))
527                                 die("unable to rename temporary pack file: %s",
528                                     strerror(errno));
530                         /*
531                          * Packs are runtime accessed in their mtime
532                          * order since newer packs are more likely to contain
533                          * younger objects.  So if we are creating multiple
534                          * packs then we should modify the mtime of later ones
535                          * to preserve this property.
536                          */
537                         if (stat(tmpname, &st) < 0) {
538                                 warning("failed to stat %s: %s",
539                                         tmpname, strerror(errno));
540                         } else if (!last_mtime) {
541                                 last_mtime = st.st_mtime;
542                         } else {
543                                 struct utimbuf utb;
544                                 utb.actime = st.st_atime;
545                                 utb.modtime = --last_mtime;
546                                 if (utime(tmpname, &utb) < 0)
547                                         warning("failed utime() on %s: %s",
548                                                 tmpname, strerror(errno));
549                         }
551                         snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
552                                  base_name, sha1_to_hex(sha1));
553                         if (adjust_perm(idx_tmp_name, mode))
554                                 die("unable to make temporary index file readable: %s",
555                                     strerror(errno));
556                         if (rename(idx_tmp_name, tmpname))
557                                 die("unable to rename temporary index file: %s",
558                                     strerror(errno));
560                         free(idx_tmp_name);
561                         free(pack_tmp_name);
562                         puts(sha1_to_hex(sha1));
563                 }
565                 /* mark written objects as written to previous pack */
566                 for (j = 0; j < nr_written; j++) {
567                         written_list[j]->offset = (off_t)-1;
568                 }
569                 nr_remaining -= nr_written;
570         } while (nr_remaining && i < nr_objects);
572         free(written_list);
573         stop_progress(&progress_state);
574         if (written != nr_result)
575                 die("wrote %"PRIu32" objects while expecting %"PRIu32,
576                         written, nr_result);
577         /*
578          * We have scanned through [0 ... i).  Since we have written
579          * the correct number of objects,  the remaining [i ... nr_objects)
580          * items must be either already written (due to out-of-order delta base)
581          * or a preferred base.  Count those which are neither and complain if any.
582          */
583         for (j = 0; i < nr_objects; i++) {
584                 struct object_entry *e = objects + i;
585                 j += !e->idx.offset && !e->preferred_base;
586         }
587         if (j)
588                 die("wrote %"PRIu32" objects as expected but %"PRIu32
589                         " unwritten", written, j);
592 static int locate_object_entry_hash(const unsigned char *sha1)
594         int i;
595         unsigned int ui;
596         memcpy(&ui, sha1, sizeof(unsigned int));
597         i = ui % object_ix_hashsz;
598         while (0 < object_ix[i]) {
599                 if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
600                         return i;
601                 if (++i == object_ix_hashsz)
602                         i = 0;
603         }
604         return -1 - i;
607 static struct object_entry *locate_object_entry(const unsigned char *sha1)
609         int i;
611         if (!object_ix_hashsz)
612                 return NULL;
614         i = locate_object_entry_hash(sha1);
615         if (0 <= i)
616                 return &objects[object_ix[i]-1];
617         return NULL;
620 static void rehash_objects(void)
622         uint32_t i;
623         struct object_entry *oe;
625         object_ix_hashsz = nr_objects * 3;
626         if (object_ix_hashsz < 1024)
627                 object_ix_hashsz = 1024;
628         object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
629         memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
630         for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
631                 int ix = locate_object_entry_hash(oe->idx.sha1);
632                 if (0 <= ix)
633                         continue;
634                 ix = -1 - ix;
635                 object_ix[ix] = i + 1;
636         }
639 static unsigned name_hash(const char *name)
641         unsigned char c;
642         unsigned hash = 0;
644         if (!name)
645                 return 0;
647         /*
648          * This effectively just creates a sortable number from the
649          * last sixteen non-whitespace characters. Last characters
650          * count "most", so things that end in ".c" sort together.
651          */
652         while ((c = *name++) != 0) {
653                 if (isspace(c))
654                         continue;
655                 hash = (hash >> 2) + (c << 24);
656         }
657         return hash;
660 static void setup_delta_attr_check(struct git_attr_check *check)
662         static struct git_attr *attr_delta;
664         if (!attr_delta)
665                 attr_delta = git_attr("delta", 5);
667         check[0].attr = attr_delta;
670 static int no_try_delta(const char *path)
672         struct git_attr_check check[1];
674         setup_delta_attr_check(check);
675         if (git_checkattr(path, ARRAY_SIZE(check), check))
676                 return 0;
677         if (ATTR_FALSE(check->value))
678                 return 1;
679         return 0;
682 static int add_object_entry(const unsigned char *sha1, enum object_type type,
683                             const char *name, int exclude)
685         struct object_entry *entry;
686         struct packed_git *p, *found_pack = NULL;
687         off_t found_offset = 0;
688         int ix;
689         unsigned hash = name_hash(name);
691         ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
692         if (ix >= 0) {
693                 if (exclude) {
694                         entry = objects + object_ix[ix] - 1;
695                         if (!entry->preferred_base)
696                                 nr_result--;
697                         entry->preferred_base = 1;
698                 }
699                 return 0;
700         }
702         if (!exclude && local && has_loose_object_nonlocal(sha1))
703                 return 0;
705         for (p = packed_git; p; p = p->next) {
706                 off_t offset = find_pack_entry_one(sha1, p);
707                 if (offset) {
708                         if (!found_pack) {
709                                 found_offset = offset;
710                                 found_pack = p;
711                         }
712                         if (exclude)
713                                 break;
714                         if (incremental)
715                                 return 0;
716                         if (local && !p->pack_local)
717                                 return 0;
718                         if (ignore_packed_keep && p->pack_local && p->pack_keep)
719                                 return 0;
720                 }
721         }
723         if (nr_objects >= nr_alloc) {
724                 nr_alloc = (nr_alloc  + 1024) * 3 / 2;
725                 objects = xrealloc(objects, nr_alloc * sizeof(*entry));
726         }
728         entry = objects + nr_objects++;
729         memset(entry, 0, sizeof(*entry));
730         hashcpy(entry->idx.sha1, sha1);
731         entry->hash = hash;
732         if (type)
733                 entry->type = type;
734         if (exclude)
735                 entry->preferred_base = 1;
736         else
737                 nr_result++;
738         if (found_pack) {
739                 entry->in_pack = found_pack;
740                 entry->in_pack_offset = found_offset;
741         }
743         if (object_ix_hashsz * 3 <= nr_objects * 4)
744                 rehash_objects();
745         else
746                 object_ix[-1 - ix] = nr_objects;
748         display_progress(progress_state, nr_objects);
750         if (name && no_try_delta(name))
751                 entry->no_try_delta = 1;
753         return 1;
756 struct pbase_tree_cache {
757         unsigned char sha1[20];
758         int ref;
759         int temporary;
760         void *tree_data;
761         unsigned long tree_size;
762 };
764 static struct pbase_tree_cache *(pbase_tree_cache[256]);
765 static int pbase_tree_cache_ix(const unsigned char *sha1)
767         return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
769 static int pbase_tree_cache_ix_incr(int ix)
771         return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
774 static struct pbase_tree {
775         struct pbase_tree *next;
776         /* This is a phony "cache" entry; we are not
777          * going to evict it nor find it through _get()
778          * mechanism -- this is for the toplevel node that
779          * would almost always change with any commit.
780          */
781         struct pbase_tree_cache pcache;
782 } *pbase_tree;
784 static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
786         struct pbase_tree_cache *ent, *nent;
787         void *data;
788         unsigned long size;
789         enum object_type type;
790         int neigh;
791         int my_ix = pbase_tree_cache_ix(sha1);
792         int available_ix = -1;
794         /* pbase-tree-cache acts as a limited hashtable.
795          * your object will be found at your index or within a few
796          * slots after that slot if it is cached.
797          */
798         for (neigh = 0; neigh < 8; neigh++) {
799                 ent = pbase_tree_cache[my_ix];
800                 if (ent && !hashcmp(ent->sha1, sha1)) {
801                         ent->ref++;
802                         return ent;
803                 }
804                 else if (((available_ix < 0) && (!ent || !ent->ref)) ||
805                          ((0 <= available_ix) &&
806                           (!ent && pbase_tree_cache[available_ix])))
807                         available_ix = my_ix;
808                 if (!ent)
809                         break;
810                 my_ix = pbase_tree_cache_ix_incr(my_ix);
811         }
813         /* Did not find one.  Either we got a bogus request or
814          * we need to read and perhaps cache.
815          */
816         data = read_sha1_file(sha1, &type, &size);
817         if (!data)
818                 return NULL;
819         if (type != OBJ_TREE) {
820                 free(data);
821                 return NULL;
822         }
824         /* We need to either cache or return a throwaway copy */
826         if (available_ix < 0)
827                 ent = NULL;
828         else {
829                 ent = pbase_tree_cache[available_ix];
830                 my_ix = available_ix;
831         }
833         if (!ent) {
834                 nent = xmalloc(sizeof(*nent));
835                 nent->temporary = (available_ix < 0);
836         }
837         else {
838                 /* evict and reuse */
839                 free(ent->tree_data);
840                 nent = ent;
841         }
842         hashcpy(nent->sha1, sha1);
843         nent->tree_data = data;
844         nent->tree_size = size;
845         nent->ref = 1;
846         if (!nent->temporary)
847                 pbase_tree_cache[my_ix] = nent;
848         return nent;
851 static void pbase_tree_put(struct pbase_tree_cache *cache)
853         if (!cache->temporary) {
854                 cache->ref--;
855                 return;
856         }
857         free(cache->tree_data);
858         free(cache);
861 static int name_cmp_len(const char *name)
863         int i;
864         for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
865                 ;
866         return i;
869 static void add_pbase_object(struct tree_desc *tree,
870                              const char *name,
871                              int cmplen,
872                              const char *fullname)
874         struct name_entry entry;
875         int cmp;
877         while (tree_entry(tree,&entry)) {
878                 if (S_ISGITLINK(entry.mode))
879                         continue;
880                 cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
881                       memcmp(name, entry.path, cmplen);
882                 if (cmp > 0)
883                         continue;
884                 if (cmp < 0)
885                         return;
886                 if (name[cmplen] != '/') {
887                         add_object_entry(entry.sha1,
888                                          object_type(entry.mode),
889                                          fullname, 1);
890                         return;
891                 }
892                 if (S_ISDIR(entry.mode)) {
893                         struct tree_desc sub;
894                         struct pbase_tree_cache *tree;
895                         const char *down = name+cmplen+1;
896                         int downlen = name_cmp_len(down);
898                         tree = pbase_tree_get(entry.sha1);
899                         if (!tree)
900                                 return;
901                         init_tree_desc(&sub, tree->tree_data, tree->tree_size);
903                         add_pbase_object(&sub, down, downlen, fullname);
904                         pbase_tree_put(tree);
905                 }
906         }
909 static unsigned *done_pbase_paths;
910 static int done_pbase_paths_num;
911 static int done_pbase_paths_alloc;
912 static int done_pbase_path_pos(unsigned hash)
914         int lo = 0;
915         int hi = done_pbase_paths_num;
916         while (lo < hi) {
917                 int mi = (hi + lo) / 2;
918                 if (done_pbase_paths[mi] == hash)
919                         return mi;
920                 if (done_pbase_paths[mi] < hash)
921                         hi = mi;
922                 else
923                         lo = mi + 1;
924         }
925         return -lo-1;
928 static int check_pbase_path(unsigned hash)
930         int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
931         if (0 <= pos)
932                 return 1;
933         pos = -pos - 1;
934         if (done_pbase_paths_alloc <= done_pbase_paths_num) {
935                 done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
936                 done_pbase_paths = xrealloc(done_pbase_paths,
937                                             done_pbase_paths_alloc *
938                                             sizeof(unsigned));
939         }
940         done_pbase_paths_num++;
941         if (pos < done_pbase_paths_num)
942                 memmove(done_pbase_paths + pos + 1,
943                         done_pbase_paths + pos,
944                         (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
945         done_pbase_paths[pos] = hash;
946         return 0;
949 static void add_preferred_base_object(const char *name)
951         struct pbase_tree *it;
952         int cmplen;
953         unsigned hash = name_hash(name);
955         if (!num_preferred_base || check_pbase_path(hash))
956                 return;
958         cmplen = name_cmp_len(name);
959         for (it = pbase_tree; it; it = it->next) {
960                 if (cmplen == 0) {
961                         add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
962                 }
963                 else {
964                         struct tree_desc tree;
965                         init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
966                         add_pbase_object(&tree, name, cmplen, name);
967                 }
968         }
971 static void add_preferred_base(unsigned char *sha1)
973         struct pbase_tree *it;
974         void *data;
975         unsigned long size;
976         unsigned char tree_sha1[20];
978         if (window <= num_preferred_base++)
979                 return;
981         data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
982         if (!data)
983                 return;
985         for (it = pbase_tree; it; it = it->next) {
986                 if (!hashcmp(it->pcache.sha1, tree_sha1)) {
987                         free(data);
988                         return;
989                 }
990         }
992         it = xcalloc(1, sizeof(*it));
993         it->next = pbase_tree;
994         pbase_tree = it;
996         hashcpy(it->pcache.sha1, tree_sha1);
997         it->pcache.tree_data = data;
998         it->pcache.tree_size = size;
1001 static void check_object(struct object_entry *entry)
1003         if (entry->in_pack) {
1004                 struct packed_git *p = entry->in_pack;
1005                 struct pack_window *w_curs = NULL;
1006                 const unsigned char *base_ref = NULL;
1007                 struct object_entry *base_entry;
1008                 unsigned long used, used_0;
1009                 unsigned int avail;
1010                 off_t ofs;
1011                 unsigned char *buf, c;
1013                 buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1015                 /*
1016                  * We want in_pack_type even if we do not reuse delta
1017                  * since non-delta representations could still be reused.
1018                  */
1019                 used = unpack_object_header_gently(buf, avail,
1020                                                    &entry->in_pack_type,
1021                                                    &entry->size);
1023                 /*
1024                  * Determine if this is a delta and if so whether we can
1025                  * reuse it or not.  Otherwise let's find out as cheaply as
1026                  * possible what the actual type and size for this object is.
1027                  */
1028                 switch (entry->in_pack_type) {
1029                 default:
1030                         /* Not a delta hence we've already got all we need. */
1031                         entry->type = entry->in_pack_type;
1032                         entry->in_pack_header_size = used;
1033                         unuse_pack(&w_curs);
1034                         return;
1035                 case OBJ_REF_DELTA:
1036                         if (reuse_delta && !entry->preferred_base)
1037                                 base_ref = use_pack(p, &w_curs,
1038                                                 entry->in_pack_offset + used, NULL);
1039                         entry->in_pack_header_size = used + 20;
1040                         break;
1041                 case OBJ_OFS_DELTA:
1042                         buf = use_pack(p, &w_curs,
1043                                        entry->in_pack_offset + used, NULL);
1044                         used_0 = 0;
1045                         c = buf[used_0++];
1046                         ofs = c & 127;
1047                         while (c & 128) {
1048                                 ofs += 1;
1049                                 if (!ofs || MSB(ofs, 7))
1050                                         die("delta base offset overflow in pack for %s",
1051                                             sha1_to_hex(entry->idx.sha1));
1052                                 c = buf[used_0++];
1053                                 ofs = (ofs << 7) + (c & 127);
1054                         }
1055                         if (ofs >= entry->in_pack_offset)
1056                                 die("delta base offset out of bound for %s",
1057                                     sha1_to_hex(entry->idx.sha1));
1058                         ofs = entry->in_pack_offset - ofs;
1059                         if (reuse_delta && !entry->preferred_base) {
1060                                 struct revindex_entry *revidx;
1061                                 revidx = find_pack_revindex(p, ofs);
1062                                 base_ref = nth_packed_object_sha1(p, revidx->nr);
1063                         }
1064                         entry->in_pack_header_size = used + used_0;
1065                         break;
1066                 }
1068                 if (base_ref && (base_entry = locate_object_entry(base_ref))) {
1069                         /*
1070                          * If base_ref was set above that means we wish to
1071                          * reuse delta data, and we even found that base
1072                          * in the list of objects we want to pack. Goodie!
1073                          *
1074                          * Depth value does not matter - find_deltas() will
1075                          * never consider reused delta as the base object to
1076                          * deltify other objects against, in order to avoid
1077                          * circular deltas.
1078                          */
1079                         entry->type = entry->in_pack_type;
1080                         entry->delta = base_entry;
1081                         entry->delta_sibling = base_entry->delta_child;
1082                         base_entry->delta_child = entry;
1083                         unuse_pack(&w_curs);
1084                         return;
1085                 }
1087                 if (entry->type) {
1088                         /*
1089                          * This must be a delta and we already know what the
1090                          * final object type is.  Let's extract the actual
1091                          * object size from the delta header.
1092                          */
1093                         entry->size = get_size_from_delta(p, &w_curs,
1094                                         entry->in_pack_offset + entry->in_pack_header_size);
1095                         unuse_pack(&w_curs);
1096                         return;
1097                 }
1099                 /*
1100                  * No choice but to fall back to the recursive delta walk
1101                  * with sha1_object_info() to find about the object type
1102                  * at this point...
1103                  */
1104                 unuse_pack(&w_curs);
1105         }
1107         entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
1108         /*
1109          * The error condition is checked in prepare_pack().  This is
1110          * to permit a missing preferred base object to be ignored
1111          * as a preferred base.  Doing so can result in a larger
1112          * pack file, but the transfer will still take place.
1113          */
1116 static int pack_offset_sort(const void *_a, const void *_b)
1118         const struct object_entry *a = *(struct object_entry **)_a;
1119         const struct object_entry *b = *(struct object_entry **)_b;
1121         /* avoid filesystem trashing with loose objects */
1122         if (!a->in_pack && !b->in_pack)
1123                 return hashcmp(a->idx.sha1, b->idx.sha1);
1125         if (a->in_pack < b->in_pack)
1126                 return -1;
1127         if (a->in_pack > b->in_pack)
1128                 return 1;
1129         return a->in_pack_offset < b->in_pack_offset ? -1 :
1130                         (a->in_pack_offset > b->in_pack_offset);
1133 static void get_object_details(void)
1135         uint32_t i;
1136         struct object_entry **sorted_by_offset;
1138         sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
1139         for (i = 0; i < nr_objects; i++)
1140                 sorted_by_offset[i] = objects + i;
1141         qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
1143         for (i = 0; i < nr_objects; i++)
1144                 check_object(sorted_by_offset[i]);
1146         free(sorted_by_offset);
1149 /*
1150  * We search for deltas in a list sorted by type, by filename hash, and then
1151  * by size, so that we see progressively smaller and smaller files.
1152  * That's because we prefer deltas to be from the bigger file
1153  * to the smaller -- deletes are potentially cheaper, but perhaps
1154  * more importantly, the bigger file is likely the more recent
1155  * one.  The deepest deltas are therefore the oldest objects which are
1156  * less susceptible to be accessed often.
1157  */
1158 static int type_size_sort(const void *_a, const void *_b)
1160         const struct object_entry *a = *(struct object_entry **)_a;
1161         const struct object_entry *b = *(struct object_entry **)_b;
1163         if (a->type > b->type)
1164                 return -1;
1165         if (a->type < b->type)
1166                 return 1;
1167         if (a->hash > b->hash)
1168                 return -1;
1169         if (a->hash < b->hash)
1170                 return 1;
1171         if (a->preferred_base > b->preferred_base)
1172                 return -1;
1173         if (a->preferred_base < b->preferred_base)
1174                 return 1;
1175         if (a->size > b->size)
1176                 return -1;
1177         if (a->size < b->size)
1178                 return 1;
1179         return a < b ? -1 : (a > b);  /* newest first */
1182 struct unpacked {
1183         struct object_entry *entry;
1184         void *data;
1185         struct delta_index *index;
1186         unsigned depth;
1187 };
1189 static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
1190                            unsigned long delta_size)
1192         if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1193                 return 0;
1195         if (delta_size < cache_max_small_delta_size)
1196                 return 1;
1198         /* cache delta, if objects are large enough compared to delta size */
1199         if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1200                 return 1;
1202         return 0;
1205 #ifdef THREADED_DELTA_SEARCH
1207 static pthread_mutex_t read_mutex = PTHREAD_MUTEX_INITIALIZER;
1208 #define read_lock()             pthread_mutex_lock(&read_mutex)
1209 #define read_unlock()           pthread_mutex_unlock(&read_mutex)
1211 static pthread_mutex_t cache_mutex = PTHREAD_MUTEX_INITIALIZER;
1212 #define cache_lock()            pthread_mutex_lock(&cache_mutex)
1213 #define cache_unlock()          pthread_mutex_unlock(&cache_mutex)
1215 static pthread_mutex_t progress_mutex = PTHREAD_MUTEX_INITIALIZER;
1216 #define progress_lock()         pthread_mutex_lock(&progress_mutex)
1217 #define progress_unlock()       pthread_mutex_unlock(&progress_mutex)
1219 #else
1221 #define read_lock()             (void)0
1222 #define read_unlock()           (void)0
1223 #define cache_lock()            (void)0
1224 #define cache_unlock()          (void)0
1225 #define progress_lock()         (void)0
1226 #define progress_unlock()       (void)0
1228 #endif
1230 static int try_delta(struct unpacked *trg, struct unpacked *src,
1231                      unsigned max_depth, unsigned long *mem_usage)
1233         struct object_entry *trg_entry = trg->entry;
1234         struct object_entry *src_entry = src->entry;
1235         unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1236         unsigned ref_depth;
1237         enum object_type type;
1238         void *delta_buf;
1240         /* Don't bother doing diffs between different types */
1241         if (trg_entry->type != src_entry->type)
1242                 return -1;
1244         /*
1245          * We do not bother to try a delta that we discarded
1246          * on an earlier try, but only when reusing delta data.
1247          */
1248         if (reuse_delta && trg_entry->in_pack &&
1249             trg_entry->in_pack == src_entry->in_pack &&
1250             trg_entry->in_pack_type != OBJ_REF_DELTA &&
1251             trg_entry->in_pack_type != OBJ_OFS_DELTA)
1252                 return 0;
1254         /* Let's not bust the allowed depth. */
1255         if (src->depth >= max_depth)
1256                 return 0;
1258         /* Now some size filtering heuristics. */
1259         trg_size = trg_entry->size;
1260         if (!trg_entry->delta) {
1261                 max_size = trg_size/2 - 20;
1262                 ref_depth = 1;
1263         } else {
1264                 max_size = trg_entry->delta_size;
1265                 ref_depth = trg->depth;
1266         }
1267         max_size = max_size * (max_depth - src->depth) /
1268                                                 (max_depth - ref_depth + 1);
1269         if (max_size == 0)
1270                 return 0;
1271         src_size = src_entry->size;
1272         sizediff = src_size < trg_size ? trg_size - src_size : 0;
1273         if (sizediff >= max_size)
1274                 return 0;
1275         if (trg_size < src_size / 32)
1276                 return 0;
1278         /* Load data if not already done */
1279         if (!trg->data) {
1280                 read_lock();
1281                 trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
1282                 read_unlock();
1283                 if (!trg->data)
1284                         die("object %s cannot be read",
1285                             sha1_to_hex(trg_entry->idx.sha1));
1286                 if (sz != trg_size)
1287                         die("object %s inconsistent object length (%lu vs %lu)",
1288                             sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
1289                 *mem_usage += sz;
1290         }
1291         if (!src->data) {
1292                 read_lock();
1293                 src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
1294                 read_unlock();
1295                 if (!src->data)
1296                         die("object %s cannot be read",
1297                             sha1_to_hex(src_entry->idx.sha1));
1298                 if (sz != src_size)
1299                         die("object %s inconsistent object length (%lu vs %lu)",
1300                             sha1_to_hex(src_entry->idx.sha1), sz, src_size);
1301                 *mem_usage += sz;
1302         }
1303         if (!src->index) {
1304                 src->index = create_delta_index(src->data, src_size);
1305                 if (!src->index) {
1306                         static int warned = 0;
1307                         if (!warned++)
1308                                 warning("suboptimal pack - out of memory");
1309                         return 0;
1310                 }
1311                 *mem_usage += sizeof_delta_index(src->index);
1312         }
1314         delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1315         if (!delta_buf)
1316                 return 0;
1318         if (trg_entry->delta) {
1319                 /* Prefer only shallower same-sized deltas. */
1320                 if (delta_size == trg_entry->delta_size &&
1321                     src->depth + 1 >= trg->depth) {
1322                         free(delta_buf);
1323                         return 0;
1324                 }
1325         }
1327         /*
1328          * Handle memory allocation outside of the cache
1329          * accounting lock.  Compiler will optimize the strangeness
1330          * away when THREADED_DELTA_SEARCH is not defined.
1331          */
1332         free(trg_entry->delta_data);
1333         cache_lock();
1334         if (trg_entry->delta_data) {
1335                 delta_cache_size -= trg_entry->delta_size;
1336                 trg_entry->delta_data = NULL;
1337         }
1338         if (delta_cacheable(src_size, trg_size, delta_size)) {
1339                 delta_cache_size += delta_size;
1340                 cache_unlock();
1341                 trg_entry->delta_data = xrealloc(delta_buf, delta_size);
1342         } else {
1343                 cache_unlock();
1344                 free(delta_buf);
1345         }
1347         trg_entry->delta = src_entry;
1348         trg_entry->delta_size = delta_size;
1349         trg->depth = src->depth + 1;
1351         return 1;
1354 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1356         struct object_entry *child = me->delta_child;
1357         unsigned int m = n;
1358         while (child) {
1359                 unsigned int c = check_delta_limit(child, n + 1);
1360                 if (m < c)
1361                         m = c;
1362                 child = child->delta_sibling;
1363         }
1364         return m;
1367 static unsigned long free_unpacked(struct unpacked *n)
1369         unsigned long freed_mem = sizeof_delta_index(n->index);
1370         free_delta_index(n->index);
1371         n->index = NULL;
1372         if (n->data) {
1373                 freed_mem += n->entry->size;
1374                 free(n->data);
1375                 n->data = NULL;
1376         }
1377         n->entry = NULL;
1378         n->depth = 0;
1379         return freed_mem;
1382 static void find_deltas(struct object_entry **list, unsigned *list_size,
1383                         int window, int depth, unsigned *processed)
1385         uint32_t i, idx = 0, count = 0;
1386         struct unpacked *array;
1387         unsigned long mem_usage = 0;
1389         array = xcalloc(window, sizeof(struct unpacked));
1391         for (;;) {
1392                 struct object_entry *entry;
1393                 struct unpacked *n = array + idx;
1394                 int j, max_depth, best_base = -1;
1396                 progress_lock();
1397                 if (!*list_size) {
1398                         progress_unlock();
1399                         break;
1400                 }
1401                 entry = *list++;
1402                 (*list_size)--;
1403                 if (!entry->preferred_base) {
1404                         (*processed)++;
1405                         display_progress(progress_state, *processed);
1406                 }
1407                 progress_unlock();
1409                 mem_usage -= free_unpacked(n);
1410                 n->entry = entry;
1412                 while (window_memory_limit &&
1413                        mem_usage > window_memory_limit &&
1414                        count > 1) {
1415                         uint32_t tail = (idx + window - count) % window;
1416                         mem_usage -= free_unpacked(array + tail);
1417                         count--;
1418                 }
1420                 /* We do not compute delta to *create* objects we are not
1421                  * going to pack.
1422                  */
1423                 if (entry->preferred_base)
1424                         goto next;
1426                 /*
1427                  * If the current object is at pack edge, take the depth the
1428                  * objects that depend on the current object into account
1429                  * otherwise they would become too deep.
1430                  */
1431                 max_depth = depth;
1432                 if (entry->delta_child) {
1433                         max_depth -= check_delta_limit(entry, 0);
1434                         if (max_depth <= 0)
1435                                 goto next;
1436                 }
1438                 j = window;
1439                 while (--j > 0) {
1440                         int ret;
1441                         uint32_t other_idx = idx + j;
1442                         struct unpacked *m;
1443                         if (other_idx >= window)
1444                                 other_idx -= window;
1445                         m = array + other_idx;
1446                         if (!m->entry)
1447                                 break;
1448                         ret = try_delta(n, m, max_depth, &mem_usage);
1449                         if (ret < 0)
1450                                 break;
1451                         else if (ret > 0)
1452                                 best_base = other_idx;
1453                 }
1455                 /*
1456                  * If we decided to cache the delta data, then it is best
1457                  * to compress it right away.  First because we have to do
1458                  * it anyway, and doing it here while we're threaded will
1459                  * save a lot of time in the non threaded write phase,
1460                  * as well as allow for caching more deltas within
1461                  * the same cache size limit.
1462                  * ...
1463                  * But only if not writing to stdout, since in that case
1464                  * the network is most likely throttling writes anyway,
1465                  * and therefore it is best to go to the write phase ASAP
1466                  * instead, as we can afford spending more time compressing
1467                  * between writes at that moment.
1468                  */
1469                 if (entry->delta_data && !pack_to_stdout) {
1470                         entry->z_delta_size = do_compress(&entry->delta_data,
1471                                                           entry->delta_size);
1472                         cache_lock();
1473                         delta_cache_size -= entry->delta_size;
1474                         delta_cache_size += entry->z_delta_size;
1475                         cache_unlock();
1476                 }
1478                 /* if we made n a delta, and if n is already at max
1479                  * depth, leaving it in the window is pointless.  we
1480                  * should evict it first.
1481                  */
1482                 if (entry->delta && max_depth <= n->depth)
1483                         continue;
1485                 /*
1486                  * Move the best delta base up in the window, after the
1487                  * currently deltified object, to keep it longer.  It will
1488                  * be the first base object to be attempted next.
1489                  */
1490                 if (entry->delta) {
1491                         struct unpacked swap = array[best_base];
1492                         int dist = (window + idx - best_base) % window;
1493                         int dst = best_base;
1494                         while (dist--) {
1495                                 int src = (dst + 1) % window;
1496                                 array[dst] = array[src];
1497                                 dst = src;
1498                         }
1499                         array[dst] = swap;
1500                 }
1502                 next:
1503                 idx++;
1504                 if (count + 1 < window)
1505                         count++;
1506                 if (idx >= window)
1507                         idx = 0;
1508         }
1510         for (i = 0; i < window; ++i) {
1511                 free_delta_index(array[i].index);
1512                 free(array[i].data);
1513         }
1514         free(array);
1517 #ifdef THREADED_DELTA_SEARCH
1519 /*
1520  * The main thread waits on the condition that (at least) one of the workers
1521  * has stopped working (which is indicated in the .working member of
1522  * struct thread_params).
1523  * When a work thread has completed its work, it sets .working to 0 and
1524  * signals the main thread and waits on the condition that .data_ready
1525  * becomes 1.
1526  */
1528 struct thread_params {
1529         pthread_t thread;
1530         struct object_entry **list;
1531         unsigned list_size;
1532         unsigned remaining;
1533         int window;
1534         int depth;
1535         int working;
1536         int data_ready;
1537         pthread_mutex_t mutex;
1538         pthread_cond_t cond;
1539         unsigned *processed;
1540 };
1542 static pthread_cond_t progress_cond = PTHREAD_COND_INITIALIZER;
1544 static void *threaded_find_deltas(void *arg)
1546         struct thread_params *me = arg;
1548         while (me->remaining) {
1549                 find_deltas(me->list, &me->remaining,
1550                             me->window, me->depth, me->processed);
1552                 progress_lock();
1553                 me->working = 0;
1554                 pthread_cond_signal(&progress_cond);
1555                 progress_unlock();
1557                 /*
1558                  * We must not set ->data_ready before we wait on the
1559                  * condition because the main thread may have set it to 1
1560                  * before we get here. In order to be sure that new
1561                  * work is available if we see 1 in ->data_ready, it
1562                  * was initialized to 0 before this thread was spawned
1563                  * and we reset it to 0 right away.
1564                  */
1565                 pthread_mutex_lock(&me->mutex);
1566                 while (!me->data_ready)
1567                         pthread_cond_wait(&me->cond, &me->mutex);
1568                 me->data_ready = 0;
1569                 pthread_mutex_unlock(&me->mutex);
1570         }
1571         /* leave ->working 1 so that this doesn't get more work assigned */
1572         return NULL;
1575 static void ll_find_deltas(struct object_entry **list, unsigned list_size,
1576                            int window, int depth, unsigned *processed)
1578         struct thread_params p[delta_search_threads];
1579         int i, ret, active_threads = 0;
1581         if (delta_search_threads <= 1) {
1582                 find_deltas(list, &list_size, window, depth, processed);
1583                 return;
1584         }
1586         /* Partition the work amongst work threads. */
1587         for (i = 0; i < delta_search_threads; i++) {
1588                 unsigned sub_size = list_size / (delta_search_threads - i);
1590                 p[i].window = window;
1591                 p[i].depth = depth;
1592                 p[i].processed = processed;
1593                 p[i].working = 1;
1594                 p[i].data_ready = 0;
1596                 /* try to split chunks on "path" boundaries */
1597                 while (sub_size && sub_size < list_size &&
1598                        list[sub_size]->hash &&
1599                        list[sub_size]->hash == list[sub_size-1]->hash)
1600                         sub_size++;
1602                 p[i].list = list;
1603                 p[i].list_size = sub_size;
1604                 p[i].remaining = sub_size;
1606                 list += sub_size;
1607                 list_size -= sub_size;
1608         }
1610         /* Start work threads. */
1611         for (i = 0; i < delta_search_threads; i++) {
1612                 if (!p[i].list_size)
1613                         continue;
1614                 pthread_mutex_init(&p[i].mutex, NULL);
1615                 pthread_cond_init(&p[i].cond, NULL);
1616                 ret = pthread_create(&p[i].thread, NULL,
1617                                      threaded_find_deltas, &p[i]);
1618                 if (ret)
1619                         die("unable to create thread: %s", strerror(ret));
1620                 active_threads++;
1621         }
1623         /*
1624          * Now let's wait for work completion.  Each time a thread is done
1625          * with its work, we steal half of the remaining work from the
1626          * thread with the largest number of unprocessed objects and give
1627          * it to that newly idle thread.  This ensure good load balancing
1628          * until the remaining object list segments are simply too short
1629          * to be worth splitting anymore.
1630          */
1631         while (active_threads) {
1632                 struct thread_params *target = NULL;
1633                 struct thread_params *victim = NULL;
1634                 unsigned sub_size = 0;
1636                 progress_lock();
1637                 for (;;) {
1638                         for (i = 0; !target && i < delta_search_threads; i++)
1639                                 if (!p[i].working)
1640                                         target = &p[i];
1641                         if (target)
1642                                 break;
1643                         pthread_cond_wait(&progress_cond, &progress_mutex);
1644                 }
1646                 for (i = 0; i < delta_search_threads; i++)
1647                         if (p[i].remaining > 2*window &&
1648                             (!victim || victim->remaining < p[i].remaining))
1649                                 victim = &p[i];
1650                 if (victim) {
1651                         sub_size = victim->remaining / 2;
1652                         list = victim->list + victim->list_size - sub_size;
1653                         while (sub_size && list[0]->hash &&
1654                                list[0]->hash == list[-1]->hash) {
1655                                 list++;
1656                                 sub_size--;
1657                         }
1658                         if (!sub_size) {
1659                                 /*
1660                                  * It is possible for some "paths" to have
1661                                  * so many objects that no hash boundary
1662                                  * might be found.  Let's just steal the
1663                                  * exact half in that case.
1664                                  */
1665                                 sub_size = victim->remaining / 2;
1666                                 list -= sub_size;
1667                         }
1668                         target->list = list;
1669                         victim->list_size -= sub_size;
1670                         victim->remaining -= sub_size;
1671                 }
1672                 target->list_size = sub_size;
1673                 target->remaining = sub_size;
1674                 target->working = 1;
1675                 progress_unlock();
1677                 pthread_mutex_lock(&target->mutex);
1678                 target->data_ready = 1;
1679                 pthread_cond_signal(&target->cond);
1680                 pthread_mutex_unlock(&target->mutex);
1682                 if (!sub_size) {
1683                         pthread_join(target->thread, NULL);
1684                         pthread_cond_destroy(&target->cond);
1685                         pthread_mutex_destroy(&target->mutex);
1686                         active_threads--;
1687                 }
1688         }
1691 #else
1692 #define ll_find_deltas(l, s, w, d, p)   find_deltas(l, &s, w, d, p)
1693 #endif
1695 static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1697         unsigned char peeled[20];
1699         if (!prefixcmp(path, "refs/tags/") && /* is a tag? */
1700             !peel_ref(path, peeled)        && /* peelable? */
1701             !is_null_sha1(peeled)          && /* annotated tag? */
1702             locate_object_entry(peeled))      /* object packed? */
1703                 add_object_entry(sha1, OBJ_TAG, NULL, 0);
1704         return 0;
1707 static void prepare_pack(int window, int depth)
1709         struct object_entry **delta_list;
1710         uint32_t i, nr_deltas;
1711         unsigned n;
1713         get_object_details();
1715         if (!nr_objects || !window || !depth)
1716                 return;
1718         delta_list = xmalloc(nr_objects * sizeof(*delta_list));
1719         nr_deltas = n = 0;
1721         for (i = 0; i < nr_objects; i++) {
1722                 struct object_entry *entry = objects + i;
1724                 if (entry->delta)
1725                         /* This happens if we decided to reuse existing
1726                          * delta from a pack.  "reuse_delta &&" is implied.
1727                          */
1728                         continue;
1730                 if (entry->size < 50)
1731                         continue;
1733                 if (entry->no_try_delta)
1734                         continue;
1736                 if (!entry->preferred_base) {
1737                         nr_deltas++;
1738                         if (entry->type < 0)
1739                                 die("unable to get type of object %s",
1740                                     sha1_to_hex(entry->idx.sha1));
1741                 } else {
1742                         if (entry->type < 0) {
1743                                 /*
1744                                  * This object is not found, but we
1745                                  * don't have to include it anyway.
1746                                  */
1747                                 continue;
1748                         }
1749                 }
1751                 delta_list[n++] = entry;
1752         }
1754         if (nr_deltas && n > 1) {
1755                 unsigned nr_done = 0;
1756                 if (progress)
1757                         progress_state = start_progress("Compressing objects",
1758                                                         nr_deltas);
1759                 qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
1760                 ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
1761                 stop_progress(&progress_state);
1762                 if (nr_done != nr_deltas)
1763                         die("inconsistency with delta count");
1764         }
1765         free(delta_list);
1768 static int git_pack_config(const char *k, const char *v, void *cb)
1770         if(!strcmp(k, "pack.window")) {
1771                 window = git_config_int(k, v);
1772                 return 0;
1773         }
1774         if (!strcmp(k, "pack.windowmemory")) {
1775                 window_memory_limit = git_config_ulong(k, v);
1776                 return 0;
1777         }
1778         if (!strcmp(k, "pack.depth")) {
1779                 depth = git_config_int(k, v);
1780                 return 0;
1781         }
1782         if (!strcmp(k, "pack.compression")) {
1783                 int level = git_config_int(k, v);
1784                 if (level == -1)
1785                         level = Z_DEFAULT_COMPRESSION;
1786                 else if (level < 0 || level > Z_BEST_COMPRESSION)
1787                         die("bad pack compression level %d", level);
1788                 pack_compression_level = level;
1789                 pack_compression_seen = 1;
1790                 return 0;
1791         }
1792         if (!strcmp(k, "pack.deltacachesize")) {
1793                 max_delta_cache_size = git_config_int(k, v);
1794                 return 0;
1795         }
1796         if (!strcmp(k, "pack.deltacachelimit")) {
1797                 cache_max_small_delta_size = git_config_int(k, v);
1798                 return 0;
1799         }
1800         if (!strcmp(k, "pack.threads")) {
1801                 delta_search_threads = git_config_int(k, v);
1802                 if (delta_search_threads < 0)
1803                         die("invalid number of threads specified (%d)",
1804                             delta_search_threads);
1805 #ifndef THREADED_DELTA_SEARCH
1806                 if (delta_search_threads != 1)
1807                         warning("no threads support, ignoring %s", k);
1808 #endif
1809                 return 0;
1810         }
1811         if (!strcmp(k, "pack.indexversion")) {
1812                 pack_idx_default_version = git_config_int(k, v);
1813                 if (pack_idx_default_version > 2)
1814                         die("bad pack.indexversion=%"PRIu32,
1815                                 pack_idx_default_version);
1816                 return 0;
1817         }
1818         if (!strcmp(k, "pack.packsizelimit")) {
1819                 pack_size_limit_cfg = git_config_ulong(k, v);
1820                 return 0;
1821         }
1822         return git_default_config(k, v, cb);
1825 static void read_object_list_from_stdin(void)
1827         char line[40 + 1 + PATH_MAX + 2];
1828         unsigned char sha1[20];
1830         for (;;) {
1831                 if (!fgets(line, sizeof(line), stdin)) {
1832                         if (feof(stdin))
1833                                 break;
1834                         if (!ferror(stdin))
1835                                 die("fgets returned NULL, not EOF, not error!");
1836                         if (errno != EINTR)
1837                                 die("fgets: %s", strerror(errno));
1838                         clearerr(stdin);
1839                         continue;
1840                 }
1841                 if (line[0] == '-') {
1842                         if (get_sha1_hex(line+1, sha1))
1843                                 die("expected edge sha1, got garbage:\n %s",
1844                                     line);
1845                         add_preferred_base(sha1);
1846                         continue;
1847                 }
1848                 if (get_sha1_hex(line, sha1))
1849                         die("expected sha1, got garbage:\n %s", line);
1851                 add_preferred_base_object(line+41);
1852                 add_object_entry(sha1, 0, line+41, 0);
1853         }
1856 #define OBJECT_ADDED (1u<<20)
1858 static void show_commit(struct commit *commit)
1860         add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
1861         commit->object.flags |= OBJECT_ADDED;
1864 static void show_object(struct object_array_entry *p)
1866         add_preferred_base_object(p->name);
1867         add_object_entry(p->item->sha1, p->item->type, p->name, 0);
1868         p->item->flags |= OBJECT_ADDED;
1871 static void show_edge(struct commit *commit)
1873         add_preferred_base(commit->object.sha1);
1876 struct in_pack_object {
1877         off_t offset;
1878         struct object *object;
1879 };
1881 struct in_pack {
1882         int alloc;
1883         int nr;
1884         struct in_pack_object *array;
1885 };
1887 static void mark_in_pack_object(struct object *object, struct packed_git *p, struct in_pack *in_pack)
1889         in_pack->array[in_pack->nr].offset = find_pack_entry_one(object->sha1, p);
1890         in_pack->array[in_pack->nr].object = object;
1891         in_pack->nr++;
1894 /*
1895  * Compare the objects in the offset order, in order to emulate the
1896  * "git rev-list --objects" output that produced the pack originally.
1897  */
1898 static int ofscmp(const void *a_, const void *b_)
1900         struct in_pack_object *a = (struct in_pack_object *)a_;
1901         struct in_pack_object *b = (struct in_pack_object *)b_;
1903         if (a->offset < b->offset)
1904                 return -1;
1905         else if (a->offset > b->offset)
1906                 return 1;
1907         else
1908                 return hashcmp(a->object->sha1, b->object->sha1);
1911 static void add_objects_in_unpacked_packs(struct rev_info *revs)
1913         struct packed_git *p;
1914         struct in_pack in_pack;
1915         uint32_t i;
1917         memset(&in_pack, 0, sizeof(in_pack));
1919         for (p = packed_git; p; p = p->next) {
1920                 const unsigned char *sha1;
1921                 struct object *o;
1923                 for (i = 0; i < revs->num_ignore_packed; i++) {
1924                         if (matches_pack_name(p, revs->ignore_packed[i]))
1925                                 break;
1926                 }
1927                 if (revs->num_ignore_packed <= i)
1928                         continue;
1929                 if (open_pack_index(p))
1930                         die("cannot open pack index");
1932                 ALLOC_GROW(in_pack.array,
1933                            in_pack.nr + p->num_objects,
1934                            in_pack.alloc);
1936                 for (i = 0; i < p->num_objects; i++) {
1937                         sha1 = nth_packed_object_sha1(p, i);
1938                         o = lookup_unknown_object(sha1);
1939                         if (!(o->flags & OBJECT_ADDED))
1940                                 mark_in_pack_object(o, p, &in_pack);
1941                         o->flags |= OBJECT_ADDED;
1942                 }
1943         }
1945         if (in_pack.nr) {
1946                 qsort(in_pack.array, in_pack.nr, sizeof(in_pack.array[0]),
1947                       ofscmp);
1948                 for (i = 0; i < in_pack.nr; i++) {
1949                         struct object *o = in_pack.array[i].object;
1950                         add_object_entry(o->sha1, o->type, "", 0);
1951                 }
1952         }
1953         free(in_pack.array);
1956 static void loosen_unused_packed_objects(struct rev_info *revs)
1958         struct packed_git *p;
1959         uint32_t i;
1960         const unsigned char *sha1;
1962         for (p = packed_git; p; p = p->next) {
1963                 for (i = 0; i < revs->num_ignore_packed; i++) {
1964                         if (matches_pack_name(p, revs->ignore_packed[i]))
1965                                 break;
1966                 }
1967                 if (revs->num_ignore_packed <= i)
1968                         continue;
1970                 if (open_pack_index(p))
1971                         die("cannot open pack index");
1973                 for (i = 0; i < p->num_objects; i++) {
1974                         sha1 = nth_packed_object_sha1(p, i);
1975                         if (!locate_object_entry(sha1))
1976                                 if (force_object_loose(sha1, p->mtime))
1977                                         die("unable to force loose object");
1978                 }
1979         }
1982 static void get_object_list(int ac, const char **av)
1984         struct rev_info revs;
1985         char line[1000];
1986         int flags = 0;
1988         init_revisions(&revs, NULL);
1989         save_commit_buffer = 0;
1990         setup_revisions(ac, av, &revs, NULL);
1992         while (fgets(line, sizeof(line), stdin) != NULL) {
1993                 int len = strlen(line);
1994                 if (len && line[len - 1] == '\n')
1995                         line[--len] = 0;
1996                 if (!len)
1997                         break;
1998                 if (*line == '-') {
1999                         if (!strcmp(line, "--not")) {
2000                                 flags ^= UNINTERESTING;
2001                                 continue;
2002                         }
2003                         die("not a rev '%s'", line);
2004                 }
2005                 if (handle_revision_arg(line, &revs, flags, 1))
2006                         die("bad revision '%s'", line);
2007         }
2009         if (prepare_revision_walk(&revs))
2010                 die("revision walk setup failed");
2011         mark_edges_uninteresting(revs.commits, &revs, show_edge);
2012         traverse_commit_list(&revs, show_commit, show_object);
2014         if (keep_unreachable)
2015                 add_objects_in_unpacked_packs(&revs);
2016         if (unpack_unreachable)
2017                 loosen_unused_packed_objects(&revs);
2020 static int adjust_perm(const char *path, mode_t mode)
2022         if (chmod(path, mode))
2023                 return -1;
2024         return adjust_shared_perm(path);
2027 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
2029         int use_internal_rev_list = 0;
2030         int thin = 0;
2031         uint32_t i;
2032         const char **rp_av;
2033         int rp_ac_alloc = 64;
2034         int rp_ac;
2036         rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
2038         rp_av[0] = "pack-objects";
2039         rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
2040         rp_ac = 2;
2042         git_config(git_pack_config, NULL);
2043         if (!pack_compression_seen && core_compression_seen)
2044                 pack_compression_level = core_compression_level;
2046         progress = isatty(2);
2047         for (i = 1; i < argc; i++) {
2048                 const char *arg = argv[i];
2050                 if (*arg != '-')
2051                         break;
2053                 if (!strcmp("--non-empty", arg)) {
2054                         non_empty = 1;
2055                         continue;
2056                 }
2057                 if (!strcmp("--local", arg)) {
2058                         local = 1;
2059                         continue;
2060                 }
2061                 if (!strcmp("--incremental", arg)) {
2062                         incremental = 1;
2063                         continue;
2064                 }
2065                 if (!strcmp("--honor-pack-keep", arg)) {
2066                         ignore_packed_keep = 1;
2067                         continue;
2068                 }
2069                 if (!prefixcmp(arg, "--compression=")) {
2070                         char *end;
2071                         int level = strtoul(arg+14, &end, 0);
2072                         if (!arg[14] || *end)
2073                                 usage(pack_usage);
2074                         if (level == -1)
2075                                 level = Z_DEFAULT_COMPRESSION;
2076                         else if (level < 0 || level > Z_BEST_COMPRESSION)
2077                                 die("bad pack compression level %d", level);
2078                         pack_compression_level = level;
2079                         continue;
2080                 }
2081                 if (!prefixcmp(arg, "--max-pack-size=")) {
2082                         char *end;
2083                         pack_size_limit_cfg = 0;
2084                         pack_size_limit = strtoul(arg+16, &end, 0) * 1024 * 1024;
2085                         if (!arg[16] || *end)
2086                                 usage(pack_usage);
2087                         continue;
2088                 }
2089                 if (!prefixcmp(arg, "--window=")) {
2090                         char *end;
2091                         window = strtoul(arg+9, &end, 0);
2092                         if (!arg[9] || *end)
2093                                 usage(pack_usage);
2094                         continue;
2095                 }
2096                 if (!prefixcmp(arg, "--window-memory=")) {
2097                         if (!git_parse_ulong(arg+16, &window_memory_limit))
2098                                 usage(pack_usage);
2099                         continue;
2100                 }
2101                 if (!prefixcmp(arg, "--threads=")) {
2102                         char *end;
2103                         delta_search_threads = strtoul(arg+10, &end, 0);
2104                         if (!arg[10] || *end || delta_search_threads < 0)
2105                                 usage(pack_usage);
2106 #ifndef THREADED_DELTA_SEARCH
2107                         if (delta_search_threads != 1)
2108                                 warning("no threads support, "
2109                                         "ignoring %s", arg);
2110 #endif
2111                         continue;
2112                 }
2113                 if (!prefixcmp(arg, "--depth=")) {
2114                         char *end;
2115                         depth = strtoul(arg+8, &end, 0);
2116                         if (!arg[8] || *end)
2117                                 usage(pack_usage);
2118                         continue;
2119                 }
2120                 if (!strcmp("--progress", arg)) {
2121                         progress = 1;
2122                         continue;
2123                 }
2124                 if (!strcmp("--all-progress", arg)) {
2125                         progress = 2;
2126                         continue;
2127                 }
2128                 if (!strcmp("-q", arg)) {
2129                         progress = 0;
2130                         continue;
2131                 }
2132                 if (!strcmp("--no-reuse-delta", arg)) {
2133                         reuse_delta = 0;
2134                         continue;
2135                 }
2136                 if (!strcmp("--no-reuse-object", arg)) {
2137                         reuse_object = reuse_delta = 0;
2138                         continue;
2139                 }
2140                 if (!strcmp("--delta-base-offset", arg)) {
2141                         allow_ofs_delta = 1;
2142                         continue;
2143                 }
2144                 if (!strcmp("--stdout", arg)) {
2145                         pack_to_stdout = 1;
2146                         continue;
2147                 }
2148                 if (!strcmp("--revs", arg)) {
2149                         use_internal_rev_list = 1;
2150                         continue;
2151                 }
2152                 if (!strcmp("--keep-unreachable", arg)) {
2153                         keep_unreachable = 1;
2154                         continue;
2155                 }
2156                 if (!strcmp("--unpack-unreachable", arg)) {
2157                         unpack_unreachable = 1;
2158                         continue;
2159                 }
2160                 if (!strcmp("--include-tag", arg)) {
2161                         include_tag = 1;
2162                         continue;
2163                 }
2164                 if (!strcmp("--unpacked", arg) ||
2165                     !prefixcmp(arg, "--unpacked=") ||
2166                     !strcmp("--reflog", arg) ||
2167                     !strcmp("--all", arg)) {
2168                         use_internal_rev_list = 1;
2169                         if (rp_ac >= rp_ac_alloc - 1) {
2170                                 rp_ac_alloc = alloc_nr(rp_ac_alloc);
2171                                 rp_av = xrealloc(rp_av,
2172                                                  rp_ac_alloc * sizeof(*rp_av));
2173                         }
2174                         rp_av[rp_ac++] = arg;
2175                         continue;
2176                 }
2177                 if (!strcmp("--thin", arg)) {
2178                         use_internal_rev_list = 1;
2179                         thin = 1;
2180                         rp_av[1] = "--objects-edge";
2181                         continue;
2182                 }
2183                 if (!prefixcmp(arg, "--index-version=")) {
2184                         char *c;
2185                         pack_idx_default_version = strtoul(arg + 16, &c, 10);
2186                         if (pack_idx_default_version > 2)
2187                                 die("bad %s", arg);
2188                         if (*c == ',')
2189                                 pack_idx_off32_limit = strtoul(c+1, &c, 0);
2190                         if (*c || pack_idx_off32_limit & 0x80000000)
2191                                 die("bad %s", arg);
2192                         continue;
2193                 }
2194                 usage(pack_usage);
2195         }
2197         /* Traditionally "pack-objects [options] base extra" failed;
2198          * we would however want to take refs parameter that would
2199          * have been given to upstream rev-list ourselves, which means
2200          * we somehow want to say what the base name is.  So the
2201          * syntax would be:
2202          *
2203          * pack-objects [options] base <refs...>
2204          *
2205          * in other words, we would treat the first non-option as the
2206          * base_name and send everything else to the internal revision
2207          * walker.
2208          */
2210         if (!pack_to_stdout)
2211                 base_name = argv[i++];
2213         if (pack_to_stdout != !base_name)
2214                 usage(pack_usage);
2216         if (!pack_to_stdout && !pack_size_limit)
2217                 pack_size_limit = pack_size_limit_cfg;
2219         if (pack_to_stdout && pack_size_limit)
2220                 die("--max-pack-size cannot be used to build a pack for transfer.");
2222         if (!pack_to_stdout && thin)
2223                 die("--thin cannot be used to build an indexable pack.");
2225         if (keep_unreachable && unpack_unreachable)
2226                 die("--keep-unreachable and --unpack-unreachable are incompatible.");
2228 #ifdef THREADED_DELTA_SEARCH
2229         if (!delta_search_threads)      /* --threads=0 means autodetect */
2230                 delta_search_threads = online_cpus();
2231 #endif
2233         prepare_packed_git();
2235         if (progress)
2236                 progress_state = start_progress("Counting objects", 0);
2237         if (!use_internal_rev_list)
2238                 read_object_list_from_stdin();
2239         else {
2240                 rp_av[rp_ac] = NULL;
2241                 get_object_list(rp_ac, rp_av);
2242         }
2243         if (include_tag && nr_result)
2244                 for_each_ref(add_ref_tag, NULL);
2245         stop_progress(&progress_state);
2247         if (non_empty && !nr_result)
2248                 return 0;
2249         if (nr_result)
2250                 prepare_pack(window, depth);
2251         write_pack_file();
2252         if (progress)
2253                 fprintf(stderr, "Total %"PRIu32" (delta %"PRIu32"),"
2254                         " reused %"PRIu32" (delta %"PRIu32")\n",
2255                         written, written_delta, reused, reused_delta);
2256         return 0;