Merge branch 'mk/gitweb-feature'
[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"
19
20 #ifdef THREADED_DELTA_SEARCH
21 #include "thread-utils.h"
22 #include <pthread.h>
23 #endif
24
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]";
34
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 };
58
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;
68
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;
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;
87
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;
91
92 static unsigned long window_memory_limit = 0;
93
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;
101
102 /*
103  * stats
104  */
105 static uint32_t written, written_delta;
106 static uint32_t reused, reused_delta;
107
108
109 static void *get_delta(struct object_entry *entry)
110 {
111         unsigned long size, base_size, delta_size;
112         void *buf, *base_buf, *delta_buf;
113         enum object_type type;
114
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;
128 }
129
130 static unsigned long do_compress(void **pptr, unsigned long size)
131 {
132         z_stream stream;
133         void *in, *out;
134         unsigned long maxsize;
135
136         memset(&stream, 0, sizeof(stream));
137         deflateInit(&stream, pack_compression_level);
138         maxsize = deflateBound(&stream, size);
139
140         in = *pptr;
141         out = xmalloc(maxsize);
142         *pptr = out;
143
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);
151
152         free(in);
153         return stream.total_out;
154 }
155
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)
164 {
165         int n = 1;
166         unsigned char c;
167
168         if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
169                 die("bad type %d", type);
170
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;
181 }
182
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)
192 {
193         z_stream stream;
194         unsigned char fakebuf[4096], *in;
195         int st;
196
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;
211 }
212
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)
218 {
219         unsigned char *in;
220         unsigned int avail;
221
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         }
230 }
231
232 static unsigned long write_object(struct sha1file *f,
233                                   struct object_entry *entry,
234                                   off_t write_offset)
235 {
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;
242
243         if (!pack_to_stdout)
244                 crc32_begin(f);
245
246         type = entry->type;
247
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;
259
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 */
270
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                                  */
287
288         if (!to_reuse) {
289                 no_reuse:
290                 if (!usable_delta) {
291                         buf = read_sha1_file(entry->idx.sha1, &type, &size);
292                         if (!buf)
293                                 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
294                         /*
295                          * make sure no cached delta data remains from a
296                          * previous attempt before a pack split occured.
297                          */
298                         free(entry->delta_data);
299                         entry->delta_data = NULL;
300                         entry->z_delta_size = 0;
301                 } else if (entry->delta_data) {
302                         size = entry->delta_size;
303                         buf = entry->delta_data;
304                         entry->delta_data = NULL;
305                         type = (allow_ofs_delta && entry->delta->idx.offset) ?
306                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
307                 } else {
308                         buf = get_delta(entry);
309                         size = entry->delta_size;
310                         type = (allow_ofs_delta && entry->delta->idx.offset) ?
311                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
312                 }
313
314                 if (entry->z_delta_size)
315                         datalen = entry->z_delta_size;
316                 else
317                         datalen = do_compress(&buf, size);
318
319                 /*
320                  * The object header is a byte of 'type' followed by zero or
321                  * more bytes of length.
322                  */
323                 hdrlen = encode_header(type, size, header);
324
325                 if (type == OBJ_OFS_DELTA) {
326                         /*
327                          * Deltas with relative base contain an additional
328                          * encoding of the relative offset for the delta
329                          * base from this object's position in the pack.
330                          */
331                         off_t ofs = entry->idx.offset - entry->delta->idx.offset;
332                         unsigned pos = sizeof(dheader) - 1;
333                         dheader[pos] = ofs & 127;
334                         while (ofs >>= 7)
335                                 dheader[--pos] = 128 | (--ofs & 127);
336                         if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
337                                 free(buf);
338                                 return 0;
339                         }
340                         sha1write(f, header, hdrlen);
341                         sha1write(f, dheader + pos, sizeof(dheader) - pos);
342                         hdrlen += sizeof(dheader) - pos;
343                 } else if (type == OBJ_REF_DELTA) {
344                         /*
345                          * Deltas with a base reference contain
346                          * an additional 20 bytes for the base sha1.
347                          */
348                         if (limit && hdrlen + 20 + datalen + 20 >= limit) {
349                                 free(buf);
350                                 return 0;
351                         }
352                         sha1write(f, header, hdrlen);
353                         sha1write(f, entry->delta->idx.sha1, 20);
354                         hdrlen += 20;
355                 } else {
356                         if (limit && hdrlen + datalen + 20 >= limit) {
357                                 free(buf);
358                                 return 0;
359                         }
360                         sha1write(f, header, hdrlen);
361                 }
362                 sha1write(f, buf, datalen);
363                 free(buf);
364         }
365         else {
366                 struct packed_git *p = entry->in_pack;
367                 struct pack_window *w_curs = NULL;
368                 struct revindex_entry *revidx;
369                 off_t offset;
370
371                 if (entry->delta)
372                         type = (allow_ofs_delta && entry->delta->idx.offset) ?
373                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
374                 hdrlen = encode_header(type, entry->size, header);
375
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                         error("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
382                         unuse_pack(&w_curs);
383                         goto no_reuse;
384                 }
385
386                 offset += entry->in_pack_header_size;
387                 datalen -= entry->in_pack_header_size;
388                 if (!pack_to_stdout && p->index_version == 1 &&
389                     check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) {
390                         error("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
391                         unuse_pack(&w_curs);
392                         goto no_reuse;
393                 }
394
395                 if (type == OBJ_OFS_DELTA) {
396                         off_t ofs = entry->idx.offset - entry->delta->idx.offset;
397                         unsigned pos = sizeof(dheader) - 1;
398                         dheader[pos] = ofs & 127;
399                         while (ofs >>= 7)
400                                 dheader[--pos] = 128 | (--ofs & 127);
401                         if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
402                                 unuse_pack(&w_curs);
403                                 return 0;
404                         }
405                         sha1write(f, header, hdrlen);
406                         sha1write(f, dheader + pos, sizeof(dheader) - pos);
407                         hdrlen += sizeof(dheader) - pos;
408                         reused_delta++;
409                 } else if (type == OBJ_REF_DELTA) {
410                         if (limit && hdrlen + 20 + datalen + 20 >= limit) {
411                                 unuse_pack(&w_curs);
412                                 return 0;
413                         }
414                         sha1write(f, header, hdrlen);
415                         sha1write(f, entry->delta->idx.sha1, 20);
416                         hdrlen += 20;
417                         reused_delta++;
418                 } else {
419                         if (limit && hdrlen + datalen + 20 >= limit) {
420                                 unuse_pack(&w_curs);
421                                 return 0;
422                         }
423                         sha1write(f, header, hdrlen);
424                 }
425                 copy_pack_data(f, p, &w_curs, offset, datalen);
426                 unuse_pack(&w_curs);
427                 reused++;
428         }
429         if (usable_delta)
430                 written_delta++;
431         written++;
432         if (!pack_to_stdout)
433                 entry->idx.crc32 = crc32_end(f);
434         return hdrlen + datalen;
435 }
436
437 static int write_one(struct sha1file *f,
438                                struct object_entry *e,
439                                off_t *offset)
440 {
441         unsigned long size;
442
443         /* offset is non zero if object is written already. */
444         if (e->idx.offset || e->preferred_base)
445                 return 1;
446
447         /* if we are deltified, write out base object first. */
448         if (e->delta && !write_one(f, e->delta, offset))
449                 return 0;
450
451         e->idx.offset = *offset;
452         size = write_object(f, e, *offset);
453         if (!size) {
454                 e->idx.offset = 0;
455                 return 0;
456         }
457         written_list[nr_written++] = &e->idx;
458
459         /* make sure off_t is sufficiently large not to wrap */
460         if (*offset > *offset + size)
461                 die("pack too large for current definition of off_t");
462         *offset += size;
463         return 1;
464 }
465
466 /* forward declaration for write_pack_file */
467 static int adjust_perm(const char *path, mode_t mode);
468
469 static void write_pack_file(void)
470 {
471         uint32_t i = 0, j;
472         struct sha1file *f;
473         off_t offset;
474         struct pack_header hdr;
475         uint32_t nr_remaining = nr_result;
476         time_t last_mtime = 0;
477
478         if (progress > pack_to_stdout)
479                 progress_state = start_progress("Writing objects", nr_result);
480         written_list = xmalloc(nr_objects * sizeof(*written_list));
481
482         do {
483                 unsigned char sha1[20];
484                 char *pack_tmp_name = NULL;
485
486                 if (pack_to_stdout) {
487                         f = sha1fd_throughput(1, "<stdout>", progress_state);
488                 } else {
489                         char tmpname[PATH_MAX];
490                         int fd;
491                         snprintf(tmpname, sizeof(tmpname),
492                                  "%s/pack/tmp_pack_XXXXXX", get_object_directory());
493                         fd = xmkstemp(tmpname);
494                         pack_tmp_name = xstrdup(tmpname);
495                         f = sha1fd(fd, pack_tmp_name);
496                 }
497
498                 hdr.hdr_signature = htonl(PACK_SIGNATURE);
499                 hdr.hdr_version = htonl(PACK_VERSION);
500                 hdr.hdr_entries = htonl(nr_remaining);
501                 sha1write(f, &hdr, sizeof(hdr));
502                 offset = sizeof(hdr);
503                 nr_written = 0;
504                 for (; i < nr_objects; i++) {
505                         if (!write_one(f, objects + i, &offset))
506                                 break;
507                         display_progress(progress_state, written);
508                 }
509
510                 /*
511                  * Did we write the wrong # entries in the header?
512                  * If so, rewrite it like in fast-import
513                  */
514                 if (pack_to_stdout) {
515                         sha1close(f, sha1, CSUM_CLOSE);
516                 } else if (nr_written == nr_remaining) {
517                         sha1close(f, sha1, CSUM_FSYNC);
518                 } else {
519                         int fd = sha1close(f, sha1, 0);
520                         fixup_pack_header_footer(fd, sha1, pack_tmp_name,
521                                                  nr_written, sha1, offset);
522                         close(fd);
523                 }
524
525                 if (!pack_to_stdout) {
526                         mode_t mode = umask(0);
527                         struct stat st;
528                         char *idx_tmp_name, tmpname[PATH_MAX];
529
530                         umask(mode);
531                         mode = 0444 & ~mode;
532
533                         idx_tmp_name = write_idx_file(NULL, written_list,
534                                                       nr_written, sha1);
535
536                         snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
537                                  base_name, sha1_to_hex(sha1));
538                         free_pack_by_name(tmpname);
539                         if (adjust_perm(pack_tmp_name, mode))
540                                 die("unable to make temporary pack file readable: %s",
541                                     strerror(errno));
542                         if (rename(pack_tmp_name, tmpname))
543                                 die("unable to rename temporary pack file: %s",
544                                     strerror(errno));
545
546                         /*
547                          * Packs are runtime accessed in their mtime
548                          * order since newer packs are more likely to contain
549                          * younger objects.  So if we are creating multiple
550                          * packs then we should modify the mtime of later ones
551                          * to preserve this property.
552                          */
553                         if (stat(tmpname, &st) < 0) {
554                                 warning("failed to stat %s: %s",
555                                         tmpname, strerror(errno));
556                         } else if (!last_mtime) {
557                                 last_mtime = st.st_mtime;
558                         } else {
559                                 struct utimbuf utb;
560                                 utb.actime = st.st_atime;
561                                 utb.modtime = --last_mtime;
562                                 if (utime(tmpname, &utb) < 0)
563                                         warning("failed utime() on %s: %s",
564                                                 tmpname, strerror(errno));
565                         }
566
567                         snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
568                                  base_name, sha1_to_hex(sha1));
569                         if (adjust_perm(idx_tmp_name, mode))
570                                 die("unable to make temporary index file readable: %s",
571                                     strerror(errno));
572                         if (rename(idx_tmp_name, tmpname))
573                                 die("unable to rename temporary index file: %s",
574                                     strerror(errno));
575
576                         free(idx_tmp_name);
577                         free(pack_tmp_name);
578                         puts(sha1_to_hex(sha1));
579                 }
580
581                 /* mark written objects as written to previous pack */
582                 for (j = 0; j < nr_written; j++) {
583                         written_list[j]->offset = (off_t)-1;
584                 }
585                 nr_remaining -= nr_written;
586         } while (nr_remaining && i < nr_objects);
587
588         free(written_list);
589         stop_progress(&progress_state);
590         if (written != nr_result)
591                 die("wrote %"PRIu32" objects while expecting %"PRIu32,
592                         written, nr_result);
593         /*
594          * We have scanned through [0 ... i).  Since we have written
595          * the correct number of objects,  the remaining [i ... nr_objects)
596          * items must be either already written (due to out-of-order delta base)
597          * or a preferred base.  Count those which are neither and complain if any.
598          */
599         for (j = 0; i < nr_objects; i++) {
600                 struct object_entry *e = objects + i;
601                 j += !e->idx.offset && !e->preferred_base;
602         }
603         if (j)
604                 die("wrote %"PRIu32" objects as expected but %"PRIu32
605                         " unwritten", written, j);
606 }
607
608 static int locate_object_entry_hash(const unsigned char *sha1)
609 {
610         int i;
611         unsigned int ui;
612         memcpy(&ui, sha1, sizeof(unsigned int));
613         i = ui % object_ix_hashsz;
614         while (0 < object_ix[i]) {
615                 if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
616                         return i;
617                 if (++i == object_ix_hashsz)
618                         i = 0;
619         }
620         return -1 - i;
621 }
622
623 static struct object_entry *locate_object_entry(const unsigned char *sha1)
624 {
625         int i;
626
627         if (!object_ix_hashsz)
628                 return NULL;
629
630         i = locate_object_entry_hash(sha1);
631         if (0 <= i)
632                 return &objects[object_ix[i]-1];
633         return NULL;
634 }
635
636 static void rehash_objects(void)
637 {
638         uint32_t i;
639         struct object_entry *oe;
640
641         object_ix_hashsz = nr_objects * 3;
642         if (object_ix_hashsz < 1024)
643                 object_ix_hashsz = 1024;
644         object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
645         memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
646         for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
647                 int ix = locate_object_entry_hash(oe->idx.sha1);
648                 if (0 <= ix)
649                         continue;
650                 ix = -1 - ix;
651                 object_ix[ix] = i + 1;
652         }
653 }
654
655 static unsigned name_hash(const char *name)
656 {
657         unsigned char c;
658         unsigned hash = 0;
659
660         if (!name)
661                 return 0;
662
663         /*
664          * This effectively just creates a sortable number from the
665          * last sixteen non-whitespace characters. Last characters
666          * count "most", so things that end in ".c" sort together.
667          */
668         while ((c = *name++) != 0) {
669                 if (isspace(c))
670                         continue;
671                 hash = (hash >> 2) + (c << 24);
672         }
673         return hash;
674 }
675
676 static void setup_delta_attr_check(struct git_attr_check *check)
677 {
678         static struct git_attr *attr_delta;
679
680         if (!attr_delta)
681                 attr_delta = git_attr("delta", 5);
682
683         check[0].attr = attr_delta;
684 }
685
686 static int no_try_delta(const char *path)
687 {
688         struct git_attr_check check[1];
689
690         setup_delta_attr_check(check);
691         if (git_checkattr(path, ARRAY_SIZE(check), check))
692                 return 0;
693         if (ATTR_FALSE(check->value))
694                 return 1;
695         return 0;
696 }
697
698 static int add_object_entry(const unsigned char *sha1, enum object_type type,
699                             const char *name, int exclude)
700 {
701         struct object_entry *entry;
702         struct packed_git *p, *found_pack = NULL;
703         off_t found_offset = 0;
704         int ix;
705         unsigned hash = name_hash(name);
706
707         ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
708         if (ix >= 0) {
709                 if (exclude) {
710                         entry = objects + object_ix[ix] - 1;
711                         if (!entry->preferred_base)
712                                 nr_result--;
713                         entry->preferred_base = 1;
714                 }
715                 return 0;
716         }
717
718         if (!exclude && local && has_loose_object_nonlocal(sha1))
719                 return 0;
720
721         for (p = packed_git; p; p = p->next) {
722                 off_t offset = find_pack_entry_one(sha1, p);
723                 if (offset) {
724                         if (!found_pack) {
725                                 found_offset = offset;
726                                 found_pack = p;
727                         }
728                         if (exclude)
729                                 break;
730                         if (incremental)
731                                 return 0;
732                         if (local && !p->pack_local)
733                                 return 0;
734                         if (ignore_packed_keep && p->pack_local && p->pack_keep)
735                                 return 0;
736                 }
737         }
738
739         if (nr_objects >= nr_alloc) {
740                 nr_alloc = (nr_alloc  + 1024) * 3 / 2;
741                 objects = xrealloc(objects, nr_alloc * sizeof(*entry));
742         }
743
744         entry = objects + nr_objects++;
745         memset(entry, 0, sizeof(*entry));
746         hashcpy(entry->idx.sha1, sha1);
747         entry->hash = hash;
748         if (type)
749                 entry->type = type;
750         if (exclude)
751                 entry->preferred_base = 1;
752         else
753                 nr_result++;
754         if (found_pack) {
755                 entry->in_pack = found_pack;
756                 entry->in_pack_offset = found_offset;
757         }
758
759         if (object_ix_hashsz * 3 <= nr_objects * 4)
760                 rehash_objects();
761         else
762                 object_ix[-1 - ix] = nr_objects;
763
764         display_progress(progress_state, nr_objects);
765
766         if (name && no_try_delta(name))
767                 entry->no_try_delta = 1;
768
769         return 1;
770 }
771
772 struct pbase_tree_cache {
773         unsigned char sha1[20];
774         int ref;
775         int temporary;
776         void *tree_data;
777         unsigned long tree_size;
778 };
779
780 static struct pbase_tree_cache *(pbase_tree_cache[256]);
781 static int pbase_tree_cache_ix(const unsigned char *sha1)
782 {
783         return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
784 }
785 static int pbase_tree_cache_ix_incr(int ix)
786 {
787         return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
788 }
789
790 static struct pbase_tree {
791         struct pbase_tree *next;
792         /* This is a phony "cache" entry; we are not
793          * going to evict it nor find it through _get()
794          * mechanism -- this is for the toplevel node that
795          * would almost always change with any commit.
796          */
797         struct pbase_tree_cache pcache;
798 } *pbase_tree;
799
800 static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
801 {
802         struct pbase_tree_cache *ent, *nent;
803         void *data;
804         unsigned long size;
805         enum object_type type;
806         int neigh;
807         int my_ix = pbase_tree_cache_ix(sha1);
808         int available_ix = -1;
809
810         /* pbase-tree-cache acts as a limited hashtable.
811          * your object will be found at your index or within a few
812          * slots after that slot if it is cached.
813          */
814         for (neigh = 0; neigh < 8; neigh++) {
815                 ent = pbase_tree_cache[my_ix];
816                 if (ent && !hashcmp(ent->sha1, sha1)) {
817                         ent->ref++;
818                         return ent;
819                 }
820                 else if (((available_ix < 0) && (!ent || !ent->ref)) ||
821                          ((0 <= available_ix) &&
822                           (!ent && pbase_tree_cache[available_ix])))
823                         available_ix = my_ix;
824                 if (!ent)
825                         break;
826                 my_ix = pbase_tree_cache_ix_incr(my_ix);
827         }
828
829         /* Did not find one.  Either we got a bogus request or
830          * we need to read and perhaps cache.
831          */
832         data = read_sha1_file(sha1, &type, &size);
833         if (!data)
834                 return NULL;
835         if (type != OBJ_TREE) {
836                 free(data);
837                 return NULL;
838         }
839
840         /* We need to either cache or return a throwaway copy */
841
842         if (available_ix < 0)
843                 ent = NULL;
844         else {
845                 ent = pbase_tree_cache[available_ix];
846                 my_ix = available_ix;
847         }
848
849         if (!ent) {
850                 nent = xmalloc(sizeof(*nent));
851                 nent->temporary = (available_ix < 0);
852         }
853         else {
854                 /* evict and reuse */
855                 free(ent->tree_data);
856                 nent = ent;
857         }
858         hashcpy(nent->sha1, sha1);
859         nent->tree_data = data;
860         nent->tree_size = size;
861         nent->ref = 1;
862         if (!nent->temporary)
863                 pbase_tree_cache[my_ix] = nent;
864         return nent;
865 }
866
867 static void pbase_tree_put(struct pbase_tree_cache *cache)
868 {
869         if (!cache->temporary) {
870                 cache->ref--;
871                 return;
872         }
873         free(cache->tree_data);
874         free(cache);
875 }
876
877 static int name_cmp_len(const char *name)
878 {
879         int i;
880         for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
881                 ;
882         return i;
883 }
884
885 static void add_pbase_object(struct tree_desc *tree,
886                              const char *name,
887                              int cmplen,
888                              const char *fullname)
889 {
890         struct name_entry entry;
891         int cmp;
892
893         while (tree_entry(tree,&entry)) {
894                 if (S_ISGITLINK(entry.mode))
895                         continue;
896                 cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
897                       memcmp(name, entry.path, cmplen);
898                 if (cmp > 0)
899                         continue;
900                 if (cmp < 0)
901                         return;
902                 if (name[cmplen] != '/') {
903                         add_object_entry(entry.sha1,
904                                          object_type(entry.mode),
905                                          fullname, 1);
906                         return;
907                 }
908                 if (S_ISDIR(entry.mode)) {
909                         struct tree_desc sub;
910                         struct pbase_tree_cache *tree;
911                         const char *down = name+cmplen+1;
912                         int downlen = name_cmp_len(down);
913
914                         tree = pbase_tree_get(entry.sha1);
915                         if (!tree)
916                                 return;
917                         init_tree_desc(&sub, tree->tree_data, tree->tree_size);
918
919                         add_pbase_object(&sub, down, downlen, fullname);
920                         pbase_tree_put(tree);
921                 }
922         }
923 }
924
925 static unsigned *done_pbase_paths;
926 static int done_pbase_paths_num;
927 static int done_pbase_paths_alloc;
928 static int done_pbase_path_pos(unsigned hash)
929 {
930         int lo = 0;
931         int hi = done_pbase_paths_num;
932         while (lo < hi) {
933                 int mi = (hi + lo) / 2;
934                 if (done_pbase_paths[mi] == hash)
935                         return mi;
936                 if (done_pbase_paths[mi] < hash)
937                         hi = mi;
938                 else
939                         lo = mi + 1;
940         }
941         return -lo-1;
942 }
943
944 static int check_pbase_path(unsigned hash)
945 {
946         int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
947         if (0 <= pos)
948                 return 1;
949         pos = -pos - 1;
950         if (done_pbase_paths_alloc <= done_pbase_paths_num) {
951                 done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
952                 done_pbase_paths = xrealloc(done_pbase_paths,
953                                             done_pbase_paths_alloc *
954                                             sizeof(unsigned));
955         }
956         done_pbase_paths_num++;
957         if (pos < done_pbase_paths_num)
958                 memmove(done_pbase_paths + pos + 1,
959                         done_pbase_paths + pos,
960                         (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
961         done_pbase_paths[pos] = hash;
962         return 0;
963 }
964
965 static void add_preferred_base_object(const char *name)
966 {
967         struct pbase_tree *it;
968         int cmplen;
969         unsigned hash = name_hash(name);
970
971         if (!num_preferred_base || check_pbase_path(hash))
972                 return;
973
974         cmplen = name_cmp_len(name);
975         for (it = pbase_tree; it; it = it->next) {
976                 if (cmplen == 0) {
977                         add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
978                 }
979                 else {
980                         struct tree_desc tree;
981                         init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
982                         add_pbase_object(&tree, name, cmplen, name);
983                 }
984         }
985 }
986
987 static void add_preferred_base(unsigned char *sha1)
988 {
989         struct pbase_tree *it;
990         void *data;
991         unsigned long size;
992         unsigned char tree_sha1[20];
993
994         if (window <= num_preferred_base++)
995                 return;
996
997         data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
998         if (!data)
999                 return;
1000
1001         for (it = pbase_tree; it; it = it->next) {
1002                 if (!hashcmp(it->pcache.sha1, tree_sha1)) {
1003                         free(data);
1004                         return;
1005                 }
1006         }
1007
1008         it = xcalloc(1, sizeof(*it));
1009         it->next = pbase_tree;
1010         pbase_tree = it;
1011
1012         hashcpy(it->pcache.sha1, tree_sha1);
1013         it->pcache.tree_data = data;
1014         it->pcache.tree_size = size;
1015 }
1016
1017 static void check_object(struct object_entry *entry)
1018 {
1019         if (entry->in_pack) {
1020                 struct packed_git *p = entry->in_pack;
1021                 struct pack_window *w_curs = NULL;
1022                 const unsigned char *base_ref = NULL;
1023                 struct object_entry *base_entry;
1024                 unsigned long used, used_0;
1025                 unsigned int avail;
1026                 off_t ofs;
1027                 unsigned char *buf, c;
1028
1029                 buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1030
1031                 /*
1032                  * We want in_pack_type even if we do not reuse delta
1033                  * since non-delta representations could still be reused.
1034                  */
1035                 used = unpack_object_header_buffer(buf, avail,
1036                                                    &entry->in_pack_type,
1037                                                    &entry->size);
1038                 if (used == 0)
1039                         goto give_up;
1040
1041                 /*
1042                  * Determine if this is a delta and if so whether we can
1043                  * reuse it or not.  Otherwise let's find out as cheaply as
1044                  * possible what the actual type and size for this object is.
1045                  */
1046                 switch (entry->in_pack_type) {
1047                 default:
1048                         /* Not a delta hence we've already got all we need. */
1049                         entry->type = entry->in_pack_type;
1050                         entry->in_pack_header_size = used;
1051                         if (entry->type < OBJ_COMMIT || entry->type > OBJ_BLOB)
1052                                 goto give_up;
1053                         unuse_pack(&w_curs);
1054                         return;
1055                 case OBJ_REF_DELTA:
1056                         if (reuse_delta && !entry->preferred_base)
1057                                 base_ref = use_pack(p, &w_curs,
1058                                                 entry->in_pack_offset + used, NULL);
1059                         entry->in_pack_header_size = used + 20;
1060                         break;
1061                 case OBJ_OFS_DELTA:
1062                         buf = use_pack(p, &w_curs,
1063                                        entry->in_pack_offset + used, NULL);
1064                         used_0 = 0;
1065                         c = buf[used_0++];
1066                         ofs = c & 127;
1067                         while (c & 128) {
1068                                 ofs += 1;
1069                                 if (!ofs || MSB(ofs, 7)) {
1070                                         error("delta base offset overflow in pack for %s",
1071                                               sha1_to_hex(entry->idx.sha1));
1072                                         goto give_up;
1073                                 }
1074                                 c = buf[used_0++];
1075                                 ofs = (ofs << 7) + (c & 127);
1076                         }
1077                         ofs = entry->in_pack_offset - ofs;
1078                         if (ofs <= 0 || ofs >= entry->in_pack_offset) {
1079                                 error("delta base offset out of bound for %s",
1080                                       sha1_to_hex(entry->idx.sha1));
1081                                 goto give_up;
1082                         }
1083                         if (reuse_delta && !entry->preferred_base) {
1084                                 struct revindex_entry *revidx;
1085                                 revidx = find_pack_revindex(p, ofs);
1086                                 if (!revidx)
1087                                         goto give_up;
1088                                 base_ref = nth_packed_object_sha1(p, revidx->nr);
1089                         }
1090                         entry->in_pack_header_size = used + used_0;
1091                         break;
1092                 }
1093
1094                 if (base_ref && (base_entry = locate_object_entry(base_ref))) {
1095                         /*
1096                          * If base_ref was set above that means we wish to
1097                          * reuse delta data, and we even found that base
1098                          * in the list of objects we want to pack. Goodie!
1099                          *
1100                          * Depth value does not matter - find_deltas() will
1101                          * never consider reused delta as the base object to
1102                          * deltify other objects against, in order to avoid
1103                          * circular deltas.
1104                          */
1105                         entry->type = entry->in_pack_type;
1106                         entry->delta = base_entry;
1107                         entry->delta_size = entry->size;
1108                         entry->delta_sibling = base_entry->delta_child;
1109                         base_entry->delta_child = entry;
1110                         unuse_pack(&w_curs);
1111                         return;
1112                 }
1113
1114                 if (entry->type) {
1115                         /*
1116                          * This must be a delta and we already know what the
1117                          * final object type is.  Let's extract the actual
1118                          * object size from the delta header.
1119                          */
1120                         entry->size = get_size_from_delta(p, &w_curs,
1121                                         entry->in_pack_offset + entry->in_pack_header_size);
1122                         if (entry->size == 0)
1123                                 goto give_up;
1124                         unuse_pack(&w_curs);
1125                         return;
1126                 }
1127
1128                 /*
1129                  * No choice but to fall back to the recursive delta walk
1130                  * with sha1_object_info() to find about the object type
1131                  * at this point...
1132                  */
1133                 give_up:
1134                 unuse_pack(&w_curs);
1135         }
1136
1137         entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
1138         /*
1139          * The error condition is checked in prepare_pack().  This is
1140          * to permit a missing preferred base object to be ignored
1141          * as a preferred base.  Doing so can result in a larger
1142          * pack file, but the transfer will still take place.
1143          */
1144 }
1145
1146 static int pack_offset_sort(const void *_a, const void *_b)
1147 {
1148         const struct object_entry *a = *(struct object_entry **)_a;
1149         const struct object_entry *b = *(struct object_entry **)_b;
1150
1151         /* avoid filesystem trashing with loose objects */
1152         if (!a->in_pack && !b->in_pack)
1153                 return hashcmp(a->idx.sha1, b->idx.sha1);
1154
1155         if (a->in_pack < b->in_pack)
1156                 return -1;
1157         if (a->in_pack > b->in_pack)
1158                 return 1;
1159         return a->in_pack_offset < b->in_pack_offset ? -1 :
1160                         (a->in_pack_offset > b->in_pack_offset);
1161 }
1162
1163 static void get_object_details(void)
1164 {
1165         uint32_t i;
1166         struct object_entry **sorted_by_offset;
1167
1168         sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
1169         for (i = 0; i < nr_objects; i++)
1170                 sorted_by_offset[i] = objects + i;
1171         qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
1172
1173         for (i = 0; i < nr_objects; i++)
1174                 check_object(sorted_by_offset[i]);
1175
1176         free(sorted_by_offset);
1177 }
1178
1179 /*
1180  * We search for deltas in a list sorted by type, by filename hash, and then
1181  * by size, so that we see progressively smaller and smaller files.
1182  * That's because we prefer deltas to be from the bigger file
1183  * to the smaller -- deletes are potentially cheaper, but perhaps
1184  * more importantly, the bigger file is likely the more recent
1185  * one.  The deepest deltas are therefore the oldest objects which are
1186  * less susceptible to be accessed often.
1187  */
1188 static int type_size_sort(const void *_a, const void *_b)
1189 {
1190         const struct object_entry *a = *(struct object_entry **)_a;
1191         const struct object_entry *b = *(struct object_entry **)_b;
1192
1193         if (a->type > b->type)
1194                 return -1;
1195         if (a->type < b->type)
1196                 return 1;
1197         if (a->hash > b->hash)
1198                 return -1;
1199         if (a->hash < b->hash)
1200                 return 1;
1201         if (a->preferred_base > b->preferred_base)
1202                 return -1;
1203         if (a->preferred_base < b->preferred_base)
1204                 return 1;
1205         if (a->size > b->size)
1206                 return -1;
1207         if (a->size < b->size)
1208                 return 1;
1209         return a < b ? -1 : (a > b);  /* newest first */
1210 }
1211
1212 struct unpacked {
1213         struct object_entry *entry;
1214         void *data;
1215         struct delta_index *index;
1216         unsigned depth;
1217 };
1218
1219 static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
1220                            unsigned long delta_size)
1221 {
1222         if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1223                 return 0;
1224
1225         if (delta_size < cache_max_small_delta_size)
1226                 return 1;
1227
1228         /* cache delta, if objects are large enough compared to delta size */
1229         if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1230                 return 1;
1231
1232         return 0;
1233 }
1234
1235 #ifdef THREADED_DELTA_SEARCH
1236
1237 static pthread_mutex_t read_mutex = PTHREAD_MUTEX_INITIALIZER;
1238 #define read_lock()             pthread_mutex_lock(&read_mutex)
1239 #define read_unlock()           pthread_mutex_unlock(&read_mutex)
1240
1241 static pthread_mutex_t cache_mutex = PTHREAD_MUTEX_INITIALIZER;
1242 #define cache_lock()            pthread_mutex_lock(&cache_mutex)
1243 #define cache_unlock()          pthread_mutex_unlock(&cache_mutex)
1244
1245 static pthread_mutex_t progress_mutex = PTHREAD_MUTEX_INITIALIZER;
1246 #define progress_lock()         pthread_mutex_lock(&progress_mutex)
1247 #define progress_unlock()       pthread_mutex_unlock(&progress_mutex)
1248
1249 #else
1250
1251 #define read_lock()             (void)0
1252 #define read_unlock()           (void)0
1253 #define cache_lock()            (void)0
1254 #define cache_unlock()          (void)0
1255 #define progress_lock()         (void)0
1256 #define progress_unlock()       (void)0
1257
1258 #endif
1259
1260 static int try_delta(struct unpacked *trg, struct unpacked *src,
1261                      unsigned max_depth, unsigned long *mem_usage)
1262 {
1263         struct object_entry *trg_entry = trg->entry;
1264         struct object_entry *src_entry = src->entry;
1265         unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1266         unsigned ref_depth;
1267         enum object_type type;
1268         void *delta_buf;
1269
1270         /* Don't bother doing diffs between different types */
1271         if (trg_entry->type != src_entry->type)
1272                 return -1;
1273
1274         /*
1275          * We do not bother to try a delta that we discarded
1276          * on an earlier try, but only when reusing delta data.
1277          */
1278         if (reuse_delta && trg_entry->in_pack &&
1279             trg_entry->in_pack == src_entry->in_pack &&
1280             trg_entry->in_pack_type != OBJ_REF_DELTA &&
1281             trg_entry->in_pack_type != OBJ_OFS_DELTA)
1282                 return 0;
1283
1284         /* Let's not bust the allowed depth. */
1285         if (src->depth >= max_depth)
1286                 return 0;
1287
1288         /* Now some size filtering heuristics. */
1289         trg_size = trg_entry->size;
1290         if (!trg_entry->delta) {
1291                 max_size = trg_size/2 - 20;
1292                 ref_depth = 1;
1293         } else {
1294                 max_size = trg_entry->delta_size;
1295                 ref_depth = trg->depth;
1296         }
1297         max_size = max_size * (max_depth - src->depth) /
1298                                                 (max_depth - ref_depth + 1);
1299         if (max_size == 0)
1300                 return 0;
1301         src_size = src_entry->size;
1302         sizediff = src_size < trg_size ? trg_size - src_size : 0;
1303         if (sizediff >= max_size)
1304                 return 0;
1305         if (trg_size < src_size / 32)
1306                 return 0;
1307
1308         /* Load data if not already done */
1309         if (!trg->data) {
1310                 read_lock();
1311                 trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
1312                 read_unlock();
1313                 if (!trg->data)
1314                         die("object %s cannot be read",
1315                             sha1_to_hex(trg_entry->idx.sha1));
1316                 if (sz != trg_size)
1317                         die("object %s inconsistent object length (%lu vs %lu)",
1318                             sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
1319                 *mem_usage += sz;
1320         }
1321         if (!src->data) {
1322                 read_lock();
1323                 src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
1324                 read_unlock();
1325                 if (!src->data)
1326                         die("object %s cannot be read",
1327                             sha1_to_hex(src_entry->idx.sha1));
1328                 if (sz != src_size)
1329                         die("object %s inconsistent object length (%lu vs %lu)",
1330                             sha1_to_hex(src_entry->idx.sha1), sz, src_size);
1331                 *mem_usage += sz;
1332         }
1333         if (!src->index) {
1334                 src->index = create_delta_index(src->data, src_size);
1335                 if (!src->index) {
1336                         static int warned = 0;
1337                         if (!warned++)
1338                                 warning("suboptimal pack - out of memory");
1339                         return 0;
1340                 }
1341                 *mem_usage += sizeof_delta_index(src->index);
1342         }
1343
1344         delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1345         if (!delta_buf)
1346                 return 0;
1347
1348         if (trg_entry->delta) {
1349                 /* Prefer only shallower same-sized deltas. */
1350                 if (delta_size == trg_entry->delta_size &&
1351                     src->depth + 1 >= trg->depth) {
1352                         free(delta_buf);
1353                         return 0;
1354                 }
1355         }
1356
1357         /*
1358          * Handle memory allocation outside of the cache
1359          * accounting lock.  Compiler will optimize the strangeness
1360          * away when THREADED_DELTA_SEARCH is not defined.
1361          */
1362         free(trg_entry->delta_data);
1363         cache_lock();
1364         if (trg_entry->delta_data) {
1365                 delta_cache_size -= trg_entry->delta_size;
1366                 trg_entry->delta_data = NULL;
1367         }
1368         if (delta_cacheable(src_size, trg_size, delta_size)) {
1369                 delta_cache_size += delta_size;
1370                 cache_unlock();
1371                 trg_entry->delta_data = xrealloc(delta_buf, delta_size);
1372         } else {
1373                 cache_unlock();
1374                 free(delta_buf);
1375         }
1376
1377         trg_entry->delta = src_entry;
1378         trg_entry->delta_size = delta_size;
1379         trg->depth = src->depth + 1;
1380
1381         return 1;
1382 }
1383
1384 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1385 {
1386         struct object_entry *child = me->delta_child;
1387         unsigned int m = n;
1388         while (child) {
1389                 unsigned int c = check_delta_limit(child, n + 1);
1390                 if (m < c)
1391                         m = c;
1392                 child = child->delta_sibling;
1393         }
1394         return m;
1395 }
1396
1397 static unsigned long free_unpacked(struct unpacked *n)
1398 {
1399         unsigned long freed_mem = sizeof_delta_index(n->index);
1400         free_delta_index(n->index);
1401         n->index = NULL;
1402         if (n->data) {
1403                 freed_mem += n->entry->size;
1404                 free(n->data);
1405                 n->data = NULL;
1406         }
1407         n->entry = NULL;
1408         n->depth = 0;
1409         return freed_mem;
1410 }
1411
1412 static void find_deltas(struct object_entry **list, unsigned *list_size,
1413                         int window, int depth, unsigned *processed)
1414 {
1415         uint32_t i, idx = 0, count = 0;
1416         struct unpacked *array;
1417         unsigned long mem_usage = 0;
1418
1419         array = xcalloc(window, sizeof(struct unpacked));
1420
1421         for (;;) {
1422                 struct object_entry *entry;
1423                 struct unpacked *n = array + idx;
1424                 int j, max_depth, best_base = -1;
1425
1426                 progress_lock();
1427                 if (!*list_size) {
1428                         progress_unlock();
1429                         break;
1430                 }
1431                 entry = *list++;
1432                 (*list_size)--;
1433                 if (!entry->preferred_base) {
1434                         (*processed)++;
1435                         display_progress(progress_state, *processed);
1436                 }
1437                 progress_unlock();
1438
1439                 mem_usage -= free_unpacked(n);
1440                 n->entry = entry;
1441
1442                 while (window_memory_limit &&
1443                        mem_usage > window_memory_limit &&
1444                        count > 1) {
1445                         uint32_t tail = (idx + window - count) % window;
1446                         mem_usage -= free_unpacked(array + tail);
1447                         count--;
1448                 }
1449
1450                 /* We do not compute delta to *create* objects we are not
1451                  * going to pack.
1452                  */
1453                 if (entry->preferred_base)
1454                         goto next;
1455
1456                 /*
1457                  * If the current object is at pack edge, take the depth the
1458                  * objects that depend on the current object into account
1459                  * otherwise they would become too deep.
1460                  */
1461                 max_depth = depth;
1462                 if (entry->delta_child) {
1463                         max_depth -= check_delta_limit(entry, 0);
1464                         if (max_depth <= 0)
1465                                 goto next;
1466                 }
1467
1468                 j = window;
1469                 while (--j > 0) {
1470                         int ret;
1471                         uint32_t other_idx = idx + j;
1472                         struct unpacked *m;
1473                         if (other_idx >= window)
1474                                 other_idx -= window;
1475                         m = array + other_idx;
1476                         if (!m->entry)
1477                                 break;
1478                         ret = try_delta(n, m, max_depth, &mem_usage);
1479                         if (ret < 0)
1480                                 break;
1481                         else if (ret > 0)
1482                                 best_base = other_idx;
1483                 }
1484
1485                 /*
1486                  * If we decided to cache the delta data, then it is best
1487                  * to compress it right away.  First because we have to do
1488                  * it anyway, and doing it here while we're threaded will
1489                  * save a lot of time in the non threaded write phase,
1490                  * as well as allow for caching more deltas within
1491                  * the same cache size limit.
1492                  * ...
1493                  * But only if not writing to stdout, since in that case
1494                  * the network is most likely throttling writes anyway,
1495                  * and therefore it is best to go to the write phase ASAP
1496                  * instead, as we can afford spending more time compressing
1497                  * between writes at that moment.
1498                  */
1499                 if (entry->delta_data && !pack_to_stdout) {
1500                         entry->z_delta_size = do_compress(&entry->delta_data,
1501                                                           entry->delta_size);
1502                         cache_lock();
1503                         delta_cache_size -= entry->delta_size;
1504                         delta_cache_size += entry->z_delta_size;
1505                         cache_unlock();
1506                 }
1507
1508                 /* if we made n a delta, and if n is already at max
1509                  * depth, leaving it in the window is pointless.  we
1510                  * should evict it first.
1511                  */
1512                 if (entry->delta && max_depth <= n->depth)
1513                         continue;
1514
1515                 /*
1516                  * Move the best delta base up in the window, after the
1517                  * currently deltified object, to keep it longer.  It will
1518                  * be the first base object to be attempted next.
1519                  */
1520                 if (entry->delta) {
1521                         struct unpacked swap = array[best_base];
1522                         int dist = (window + idx - best_base) % window;
1523                         int dst = best_base;
1524                         while (dist--) {
1525                                 int src = (dst + 1) % window;
1526                                 array[dst] = array[src];
1527                                 dst = src;
1528                         }
1529                         array[dst] = swap;
1530                 }
1531
1532                 next:
1533                 idx++;
1534                 if (count + 1 < window)
1535                         count++;
1536                 if (idx >= window)
1537                         idx = 0;
1538         }
1539
1540         for (i = 0; i < window; ++i) {
1541                 free_delta_index(array[i].index);
1542                 free(array[i].data);
1543         }
1544         free(array);
1545 }
1546
1547 #ifdef THREADED_DELTA_SEARCH
1548
1549 /*
1550  * The main thread waits on the condition that (at least) one of the workers
1551  * has stopped working (which is indicated in the .working member of
1552  * struct thread_params).
1553  * When a work thread has completed its work, it sets .working to 0 and
1554  * signals the main thread and waits on the condition that .data_ready
1555  * becomes 1.
1556  */
1557
1558 struct thread_params {
1559         pthread_t thread;
1560         struct object_entry **list;
1561         unsigned list_size;
1562         unsigned remaining;
1563         int window;
1564         int depth;
1565         int working;
1566         int data_ready;
1567         pthread_mutex_t mutex;
1568         pthread_cond_t cond;
1569         unsigned *processed;
1570 };
1571
1572 static pthread_cond_t progress_cond = PTHREAD_COND_INITIALIZER;
1573
1574 static void *threaded_find_deltas(void *arg)
1575 {
1576         struct thread_params *me = arg;
1577
1578         while (me->remaining) {
1579                 find_deltas(me->list, &me->remaining,
1580                             me->window, me->depth, me->processed);
1581
1582                 progress_lock();
1583                 me->working = 0;
1584                 pthread_cond_signal(&progress_cond);
1585                 progress_unlock();
1586
1587                 /*
1588                  * We must not set ->data_ready before we wait on the
1589                  * condition because the main thread may have set it to 1
1590                  * before we get here. In order to be sure that new
1591                  * work is available if we see 1 in ->data_ready, it
1592                  * was initialized to 0 before this thread was spawned
1593                  * and we reset it to 0 right away.
1594                  */
1595                 pthread_mutex_lock(&me->mutex);
1596                 while (!me->data_ready)
1597                         pthread_cond_wait(&me->cond, &me->mutex);
1598                 me->data_ready = 0;
1599                 pthread_mutex_unlock(&me->mutex);
1600         }
1601         /* leave ->working 1 so that this doesn't get more work assigned */
1602         return NULL;
1603 }
1604
1605 static void ll_find_deltas(struct object_entry **list, unsigned list_size,
1606                            int window, int depth, unsigned *processed)
1607 {
1608         struct thread_params p[delta_search_threads];
1609         int i, ret, active_threads = 0;
1610
1611         if (delta_search_threads <= 1) {
1612                 find_deltas(list, &list_size, window, depth, processed);
1613                 return;
1614         }
1615         if (progress > pack_to_stdout)
1616                 fprintf(stderr, "Delta compression using %d threads.\n",
1617                                 delta_search_threads);
1618
1619         /* Partition the work amongst work threads. */
1620         for (i = 0; i < delta_search_threads; i++) {
1621                 unsigned sub_size = list_size / (delta_search_threads - i);
1622
1623                 /* don't use too small segments or no deltas will be found */
1624                 if (sub_size < 2*window && i+1 < delta_search_threads)
1625                         sub_size = 0;
1626
1627                 p[i].window = window;
1628                 p[i].depth = depth;
1629                 p[i].processed = processed;
1630                 p[i].working = 1;
1631                 p[i].data_ready = 0;
1632
1633                 /* try to split chunks on "path" boundaries */
1634                 while (sub_size && sub_size < list_size &&
1635                        list[sub_size]->hash &&
1636                        list[sub_size]->hash == list[sub_size-1]->hash)
1637                         sub_size++;
1638
1639                 p[i].list = list;
1640                 p[i].list_size = sub_size;
1641                 p[i].remaining = sub_size;
1642
1643                 list += sub_size;
1644                 list_size -= sub_size;
1645         }
1646
1647         /* Start work threads. */
1648         for (i = 0; i < delta_search_threads; i++) {
1649                 if (!p[i].list_size)
1650                         continue;
1651                 pthread_mutex_init(&p[i].mutex, NULL);
1652                 pthread_cond_init(&p[i].cond, NULL);
1653                 ret = pthread_create(&p[i].thread, NULL,
1654                                      threaded_find_deltas, &p[i]);
1655                 if (ret)
1656                         die("unable to create thread: %s", strerror(ret));
1657                 active_threads++;
1658         }
1659
1660         /*
1661          * Now let's wait for work completion.  Each time a thread is done
1662          * with its work, we steal half of the remaining work from the
1663          * thread with the largest number of unprocessed objects and give
1664          * it to that newly idle thread.  This ensure good load balancing
1665          * until the remaining object list segments are simply too short
1666          * to be worth splitting anymore.
1667          */
1668         while (active_threads) {
1669                 struct thread_params *target = NULL;
1670                 struct thread_params *victim = NULL;
1671                 unsigned sub_size = 0;
1672
1673                 progress_lock();
1674                 for (;;) {
1675                         for (i = 0; !target && i < delta_search_threads; i++)
1676                                 if (!p[i].working)
1677                                         target = &p[i];
1678                         if (target)
1679                                 break;
1680                         pthread_cond_wait(&progress_cond, &progress_mutex);
1681                 }
1682
1683                 for (i = 0; i < delta_search_threads; i++)
1684                         if (p[i].remaining > 2*window &&
1685                             (!victim || victim->remaining < p[i].remaining))
1686                                 victim = &p[i];
1687                 if (victim) {
1688                         sub_size = victim->remaining / 2;
1689                         list = victim->list + victim->list_size - sub_size;
1690                         while (sub_size && list[0]->hash &&
1691                                list[0]->hash == list[-1]->hash) {
1692                                 list++;
1693                                 sub_size--;
1694                         }
1695                         if (!sub_size) {
1696                                 /*
1697                                  * It is possible for some "paths" to have
1698                                  * so many objects that no hash boundary
1699                                  * might be found.  Let's just steal the
1700                                  * exact half in that case.
1701                                  */
1702                                 sub_size = victim->remaining / 2;
1703                                 list -= sub_size;
1704                         }
1705                         target->list = list;
1706                         victim->list_size -= sub_size;
1707                         victim->remaining -= sub_size;
1708                 }
1709                 target->list_size = sub_size;
1710                 target->remaining = sub_size;
1711                 target->working = 1;
1712                 progress_unlock();
1713
1714                 pthread_mutex_lock(&target->mutex);
1715                 target->data_ready = 1;
1716                 pthread_cond_signal(&target->cond);
1717                 pthread_mutex_unlock(&target->mutex);
1718
1719                 if (!sub_size) {
1720                         pthread_join(target->thread, NULL);
1721                         pthread_cond_destroy(&target->cond);
1722                         pthread_mutex_destroy(&target->mutex);
1723                         active_threads--;
1724                 }
1725         }
1726 }
1727
1728 #else
1729 #define ll_find_deltas(l, s, w, d, p)   find_deltas(l, &s, w, d, p)
1730 #endif
1731
1732 static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1733 {
1734         unsigned char peeled[20];
1735
1736         if (!prefixcmp(path, "refs/tags/") && /* is a tag? */
1737             !peel_ref(path, peeled)        && /* peelable? */
1738             !is_null_sha1(peeled)          && /* annotated tag? */
1739             locate_object_entry(peeled))      /* object packed? */
1740                 add_object_entry(sha1, OBJ_TAG, NULL, 0);
1741         return 0;
1742 }
1743
1744 static void prepare_pack(int window, int depth)
1745 {
1746         struct object_entry **delta_list;
1747         uint32_t i, nr_deltas;
1748         unsigned n;
1749
1750         get_object_details();
1751
1752         /*
1753          * If we're locally repacking then we need to be doubly careful
1754          * from now on in order to make sure no stealth corruption gets
1755          * propagated to the new pack.  Clients receiving streamed packs
1756          * should validate everything they get anyway so no need to incur
1757          * the additional cost here in that case.
1758          */
1759         if (!pack_to_stdout)
1760                 do_check_packed_object_crc = 1;
1761
1762         if (!nr_objects || !window || !depth)
1763                 return;
1764
1765         delta_list = xmalloc(nr_objects * sizeof(*delta_list));
1766         nr_deltas = n = 0;
1767
1768         for (i = 0; i < nr_objects; i++) {
1769                 struct object_entry *entry = objects + i;
1770
1771                 if (entry->delta)
1772                         /* This happens if we decided to reuse existing
1773                          * delta from a pack.  "reuse_delta &&" is implied.
1774                          */
1775                         continue;
1776
1777                 if (entry->size < 50)
1778                         continue;
1779
1780                 if (entry->no_try_delta)
1781                         continue;
1782
1783                 if (!entry->preferred_base) {
1784                         nr_deltas++;
1785                         if (entry->type < 0)
1786                                 die("unable to get type of object %s",
1787                                     sha1_to_hex(entry->idx.sha1));
1788                 } else {
1789                         if (entry->type < 0) {
1790                                 /*
1791                                  * This object is not found, but we
1792                                  * don't have to include it anyway.
1793                                  */
1794                                 continue;
1795                         }
1796                 }
1797
1798                 delta_list[n++] = entry;
1799         }
1800
1801         if (nr_deltas && n > 1) {
1802                 unsigned nr_done = 0;
1803                 if (progress)
1804                         progress_state = start_progress("Compressing objects",
1805                                                         nr_deltas);
1806                 qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
1807                 ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
1808                 stop_progress(&progress_state);
1809                 if (nr_done != nr_deltas)
1810                         die("inconsistency with delta count");
1811         }
1812         free(delta_list);
1813 }
1814
1815 static int git_pack_config(const char *k, const char *v, void *cb)
1816 {
1817         if(!strcmp(k, "pack.window")) {
1818                 window = git_config_int(k, v);
1819                 return 0;
1820         }
1821         if (!strcmp(k, "pack.windowmemory")) {
1822                 window_memory_limit = git_config_ulong(k, v);
1823                 return 0;
1824         }
1825         if (!strcmp(k, "pack.depth")) {
1826                 depth = git_config_int(k, v);
1827                 return 0;
1828         }
1829         if (!strcmp(k, "pack.compression")) {
1830                 int level = git_config_int(k, v);
1831                 if (level == -1)
1832                         level = Z_DEFAULT_COMPRESSION;
1833                 else if (level < 0 || level > Z_BEST_COMPRESSION)
1834                         die("bad pack compression level %d", level);
1835                 pack_compression_level = level;
1836                 pack_compression_seen = 1;
1837                 return 0;
1838         }
1839         if (!strcmp(k, "pack.deltacachesize")) {
1840                 max_delta_cache_size = git_config_int(k, v);
1841                 return 0;
1842         }
1843         if (!strcmp(k, "pack.deltacachelimit")) {
1844                 cache_max_small_delta_size = git_config_int(k, v);
1845                 return 0;
1846         }
1847         if (!strcmp(k, "pack.threads")) {
1848                 delta_search_threads = git_config_int(k, v);
1849                 if (delta_search_threads < 0)
1850                         die("invalid number of threads specified (%d)",
1851                             delta_search_threads);
1852 #ifndef THREADED_DELTA_SEARCH
1853                 if (delta_search_threads != 1)
1854                         warning("no threads support, ignoring %s", k);
1855 #endif
1856                 return 0;
1857         }
1858         if (!strcmp(k, "pack.indexversion")) {
1859                 pack_idx_default_version = git_config_int(k, v);
1860                 if (pack_idx_default_version > 2)
1861                         die("bad pack.indexversion=%"PRIu32,
1862                                 pack_idx_default_version);
1863                 return 0;
1864         }
1865         if (!strcmp(k, "pack.packsizelimit")) {
1866                 pack_size_limit_cfg = git_config_ulong(k, v);
1867                 return 0;
1868         }
1869         return git_default_config(k, v, cb);
1870 }
1871
1872 static void read_object_list_from_stdin(void)
1873 {
1874         char line[40 + 1 + PATH_MAX + 2];
1875         unsigned char sha1[20];
1876
1877         for (;;) {
1878                 if (!fgets(line, sizeof(line), stdin)) {
1879                         if (feof(stdin))
1880                                 break;
1881                         if (!ferror(stdin))
1882                                 die("fgets returned NULL, not EOF, not error!");
1883                         if (errno != EINTR)
1884                                 die("fgets: %s", strerror(errno));
1885                         clearerr(stdin);
1886                         continue;
1887                 }
1888                 if (line[0] == '-') {
1889                         if (get_sha1_hex(line+1, sha1))
1890                                 die("expected edge sha1, got garbage:\n %s",
1891                                     line);
1892                         add_preferred_base(sha1);
1893                         continue;
1894                 }
1895                 if (get_sha1_hex(line, sha1))
1896                         die("expected sha1, got garbage:\n %s", line);
1897
1898                 add_preferred_base_object(line+41);
1899                 add_object_entry(sha1, 0, line+41, 0);
1900         }
1901 }
1902
1903 #define OBJECT_ADDED (1u<<20)
1904
1905 static void show_commit(struct commit *commit)
1906 {
1907         add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
1908         commit->object.flags |= OBJECT_ADDED;
1909 }
1910
1911 static void show_object(struct object_array_entry *p)
1912 {
1913         add_preferred_base_object(p->name);
1914         add_object_entry(p->item->sha1, p->item->type, p->name, 0);
1915         p->item->flags |= OBJECT_ADDED;
1916 }
1917
1918 static void show_edge(struct commit *commit)
1919 {
1920         add_preferred_base(commit->object.sha1);
1921 }
1922
1923 struct in_pack_object {
1924         off_t offset;
1925         struct object *object;
1926 };
1927
1928 struct in_pack {
1929         int alloc;
1930         int nr;
1931         struct in_pack_object *array;
1932 };
1933
1934 static void mark_in_pack_object(struct object *object, struct packed_git *p, struct in_pack *in_pack)
1935 {
1936         in_pack->array[in_pack->nr].offset = find_pack_entry_one(object->sha1, p);
1937         in_pack->array[in_pack->nr].object = object;
1938         in_pack->nr++;
1939 }
1940
1941 /*
1942  * Compare the objects in the offset order, in order to emulate the
1943  * "git rev-list --objects" output that produced the pack originally.
1944  */
1945 static int ofscmp(const void *a_, const void *b_)
1946 {
1947         struct in_pack_object *a = (struct in_pack_object *)a_;
1948         struct in_pack_object *b = (struct in_pack_object *)b_;
1949
1950         if (a->offset < b->offset)
1951                 return -1;
1952         else if (a->offset > b->offset)
1953                 return 1;
1954         else
1955                 return hashcmp(a->object->sha1, b->object->sha1);
1956 }
1957
1958 static void add_objects_in_unpacked_packs(struct rev_info *revs)
1959 {
1960         struct packed_git *p;
1961         struct in_pack in_pack;
1962         uint32_t i;
1963
1964         memset(&in_pack, 0, sizeof(in_pack));
1965
1966         for (p = packed_git; p; p = p->next) {
1967                 const unsigned char *sha1;
1968                 struct object *o;
1969
1970                 for (i = 0; i < revs->num_ignore_packed; i++) {
1971                         if (matches_pack_name(p, revs->ignore_packed[i]))
1972                                 break;
1973                 }
1974                 if (revs->num_ignore_packed <= i)
1975                         continue;
1976                 if (open_pack_index(p))
1977                         die("cannot open pack index");
1978
1979                 ALLOC_GROW(in_pack.array,
1980                            in_pack.nr + p->num_objects,
1981                            in_pack.alloc);
1982
1983                 for (i = 0; i < p->num_objects; i++) {
1984                         sha1 = nth_packed_object_sha1(p, i);
1985                         o = lookup_unknown_object(sha1);
1986                         if (!(o->flags & OBJECT_ADDED))
1987                                 mark_in_pack_object(o, p, &in_pack);
1988                         o->flags |= OBJECT_ADDED;
1989                 }
1990         }
1991
1992         if (in_pack.nr) {
1993                 qsort(in_pack.array, in_pack.nr, sizeof(in_pack.array[0]),
1994                       ofscmp);
1995                 for (i = 0; i < in_pack.nr; i++) {
1996                         struct object *o = in_pack.array[i].object;
1997                         add_object_entry(o->sha1, o->type, "", 0);
1998                 }
1999         }
2000         free(in_pack.array);
2001 }
2002
2003 static void loosen_unused_packed_objects(struct rev_info *revs)
2004 {
2005         struct packed_git *p;
2006         uint32_t i;
2007         const unsigned char *sha1;
2008
2009         for (p = packed_git; p; p = p->next) {
2010                 for (i = 0; i < revs->num_ignore_packed; i++) {
2011                         if (matches_pack_name(p, revs->ignore_packed[i]))
2012                                 break;
2013                 }
2014                 if (revs->num_ignore_packed <= i)
2015                         continue;
2016
2017                 if (open_pack_index(p))
2018                         die("cannot open pack index");
2019
2020                 for (i = 0; i < p->num_objects; i++) {
2021                         sha1 = nth_packed_object_sha1(p, i);
2022                         if (!locate_object_entry(sha1))
2023                                 if (force_object_loose(sha1, p->mtime))
2024                                         die("unable to force loose object");
2025                 }
2026         }
2027 }
2028
2029 static void get_object_list(int ac, const char **av)
2030 {
2031         struct rev_info revs;
2032         char line[1000];
2033         int flags = 0;
2034
2035         init_revisions(&revs, NULL);
2036         save_commit_buffer = 0;
2037         setup_revisions(ac, av, &revs, NULL);
2038
2039         while (fgets(line, sizeof(line), stdin) != NULL) {
2040                 int len = strlen(line);
2041                 if (len && line[len - 1] == '\n')
2042                         line[--len] = 0;
2043                 if (!len)
2044                         break;
2045                 if (*line == '-') {
2046                         if (!strcmp(line, "--not")) {
2047                                 flags ^= UNINTERESTING;
2048                                 continue;
2049                         }
2050                         die("not a rev '%s'", line);
2051                 }
2052                 if (handle_revision_arg(line, &revs, flags, 1))
2053                         die("bad revision '%s'", line);
2054         }
2055
2056         if (prepare_revision_walk(&revs))
2057                 die("revision walk setup failed");
2058         mark_edges_uninteresting(revs.commits, &revs, show_edge);
2059         traverse_commit_list(&revs, show_commit, show_object);
2060
2061         if (keep_unreachable)
2062                 add_objects_in_unpacked_packs(&revs);
2063         if (unpack_unreachable)
2064                 loosen_unused_packed_objects(&revs);
2065 }
2066
2067 static int adjust_perm(const char *path, mode_t mode)
2068 {
2069         if (chmod(path, mode))
2070                 return -1;
2071         return adjust_shared_perm(path);
2072 }
2073
2074 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
2075 {
2076         int use_internal_rev_list = 0;
2077         int thin = 0;
2078         uint32_t i;
2079         const char **rp_av;
2080         int rp_ac_alloc = 64;
2081         int rp_ac;
2082
2083         rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
2084
2085         rp_av[0] = "pack-objects";
2086         rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
2087         rp_ac = 2;
2088
2089         git_config(git_pack_config, NULL);
2090         if (!pack_compression_seen && core_compression_seen)
2091                 pack_compression_level = core_compression_level;
2092
2093         progress = isatty(2);
2094         for (i = 1; i < argc; i++) {
2095                 const char *arg = argv[i];
2096
2097                 if (*arg != '-')
2098                         break;
2099
2100                 if (!strcmp("--non-empty", arg)) {
2101                         non_empty = 1;
2102                         continue;
2103                 }
2104                 if (!strcmp("--local", arg)) {
2105                         local = 1;
2106                         continue;
2107                 }
2108                 if (!strcmp("--incremental", arg)) {
2109                         incremental = 1;
2110                         continue;
2111                 }
2112                 if (!strcmp("--honor-pack-keep", arg)) {
2113                         ignore_packed_keep = 1;
2114                         continue;
2115                 }
2116                 if (!prefixcmp(arg, "--compression=")) {
2117                         char *end;
2118                         int level = strtoul(arg+14, &end, 0);
2119                         if (!arg[14] || *end)
2120                                 usage(pack_usage);
2121                         if (level == -1)
2122                                 level = Z_DEFAULT_COMPRESSION;
2123                         else if (level < 0 || level > Z_BEST_COMPRESSION)
2124                                 die("bad pack compression level %d", level);
2125                         pack_compression_level = level;
2126                         continue;
2127                 }
2128                 if (!prefixcmp(arg, "--max-pack-size=")) {
2129                         char *end;
2130                         pack_size_limit_cfg = 0;
2131                         pack_size_limit = strtoul(arg+16, &end, 0) * 1024 * 1024;
2132                         if (!arg[16] || *end)
2133                                 usage(pack_usage);
2134                         continue;
2135                 }
2136                 if (!prefixcmp(arg, "--window=")) {
2137                         char *end;
2138                         window = strtoul(arg+9, &end, 0);
2139                         if (!arg[9] || *end)
2140                                 usage(pack_usage);
2141                         continue;
2142                 }
2143                 if (!prefixcmp(arg, "--window-memory=")) {
2144                         if (!git_parse_ulong(arg+16, &window_memory_limit))
2145                                 usage(pack_usage);
2146                         continue;
2147                 }
2148                 if (!prefixcmp(arg, "--threads=")) {
2149                         char *end;
2150                         delta_search_threads = strtoul(arg+10, &end, 0);
2151                         if (!arg[10] || *end || delta_search_threads < 0)
2152                                 usage(pack_usage);
2153 #ifndef THREADED_DELTA_SEARCH
2154                         if (delta_search_threads != 1)
2155                                 warning("no threads support, "
2156                                         "ignoring %s", arg);
2157 #endif
2158                         continue;
2159                 }
2160                 if (!prefixcmp(arg, "--depth=")) {
2161                         char *end;
2162                         depth = strtoul(arg+8, &end, 0);
2163                         if (!arg[8] || *end)
2164                                 usage(pack_usage);
2165                         continue;
2166                 }
2167                 if (!strcmp("--progress", arg)) {
2168                         progress = 1;
2169                         continue;
2170                 }
2171                 if (!strcmp("--all-progress", arg)) {
2172                         progress = 2;
2173                         continue;
2174                 }
2175                 if (!strcmp("-q", arg)) {
2176                         progress = 0;
2177                         continue;
2178                 }
2179                 if (!strcmp("--no-reuse-delta", arg)) {
2180                         reuse_delta = 0;
2181                         continue;
2182                 }
2183                 if (!strcmp("--no-reuse-object", arg)) {
2184                         reuse_object = reuse_delta = 0;
2185                         continue;
2186                 }
2187                 if (!strcmp("--delta-base-offset", arg)) {
2188                         allow_ofs_delta = 1;
2189                         continue;
2190                 }
2191                 if (!strcmp("--stdout", arg)) {
2192                         pack_to_stdout = 1;
2193                         continue;
2194                 }
2195                 if (!strcmp("--revs", arg)) {
2196                         use_internal_rev_list = 1;
2197                         continue;
2198                 }
2199                 if (!strcmp("--keep-unreachable", arg)) {
2200                         keep_unreachable = 1;
2201                         continue;
2202                 }
2203                 if (!strcmp("--unpack-unreachable", arg)) {
2204                         unpack_unreachable = 1;
2205                         continue;
2206                 }
2207                 if (!strcmp("--include-tag", arg)) {
2208                         include_tag = 1;
2209                         continue;
2210                 }
2211                 if (!strcmp("--unpacked", arg) ||
2212                     !prefixcmp(arg, "--unpacked=") ||
2213                     !strcmp("--reflog", arg) ||
2214                     !strcmp("--all", arg)) {
2215                         use_internal_rev_list = 1;
2216                         if (rp_ac >= rp_ac_alloc - 1) {
2217                                 rp_ac_alloc = alloc_nr(rp_ac_alloc);
2218                                 rp_av = xrealloc(rp_av,
2219                                                  rp_ac_alloc * sizeof(*rp_av));
2220                         }
2221                         rp_av[rp_ac++] = arg;
2222                         continue;
2223                 }
2224                 if (!strcmp("--thin", arg)) {
2225                         use_internal_rev_list = 1;
2226                         thin = 1;
2227                         rp_av[1] = "--objects-edge";
2228                         continue;
2229                 }
2230                 if (!prefixcmp(arg, "--index-version=")) {
2231                         char *c;
2232                         pack_idx_default_version = strtoul(arg + 16, &c, 10);
2233                         if (pack_idx_default_version > 2)
2234                                 die("bad %s", arg);
2235                         if (*c == ',')
2236                                 pack_idx_off32_limit = strtoul(c+1, &c, 0);
2237                         if (*c || pack_idx_off32_limit & 0x80000000)
2238                                 die("bad %s", arg);
2239                         continue;
2240                 }
2241                 usage(pack_usage);
2242         }
2243
2244         /* Traditionally "pack-objects [options] base extra" failed;
2245          * we would however want to take refs parameter that would
2246          * have been given to upstream rev-list ourselves, which means
2247          * we somehow want to say what the base name is.  So the
2248          * syntax would be:
2249          *
2250          * pack-objects [options] base <refs...>
2251          *
2252          * in other words, we would treat the first non-option as the
2253          * base_name and send everything else to the internal revision
2254          * walker.
2255          */
2256
2257         if (!pack_to_stdout)
2258                 base_name = argv[i++];
2259
2260         if (pack_to_stdout != !base_name)
2261                 usage(pack_usage);
2262
2263         if (!pack_to_stdout && !pack_size_limit)
2264                 pack_size_limit = pack_size_limit_cfg;
2265
2266         if (pack_to_stdout && pack_size_limit)
2267                 die("--max-pack-size cannot be used to build a pack for transfer.");
2268
2269         if (!pack_to_stdout && thin)
2270                 die("--thin cannot be used to build an indexable pack.");
2271
2272         if (keep_unreachable && unpack_unreachable)
2273                 die("--keep-unreachable and --unpack-unreachable are incompatible.");
2274
2275 #ifdef THREADED_DELTA_SEARCH
2276         if (!delta_search_threads)      /* --threads=0 means autodetect */
2277                 delta_search_threads = online_cpus();
2278 #endif
2279
2280         prepare_packed_git();
2281
2282         if (progress)
2283                 progress_state = start_progress("Counting objects", 0);
2284         if (!use_internal_rev_list)
2285                 read_object_list_from_stdin();
2286         else {
2287                 rp_av[rp_ac] = NULL;
2288                 get_object_list(rp_ac, rp_av);
2289         }
2290         if (include_tag && nr_result)
2291                 for_each_ref(add_ref_tag, NULL);
2292         stop_progress(&progress_state);
2293
2294         if (non_empty && !nr_result)
2295                 return 0;
2296         if (nr_result)
2297                 prepare_pack(window, depth);
2298         write_pack_file();
2299         if (progress)
2300                 fprintf(stderr, "Total %"PRIu32" (delta %"PRIu32"),"
2301                         " reused %"PRIu32" (delta %"PRIu32")\n",
2302                         written, written_delta, reused, reused_delta);
2303         return 0;
2304 }