Merge branch 'ah/pack-objects-usage-strings'
authorJunio C Hamano <gitster@pobox.com>
Tue, 1 Sep 2015 23:31:12 +0000 (16:31 -0700)
committerJunio C Hamano <gitster@pobox.com>
Tue, 1 Sep 2015 23:31:12 +0000 (16:31 -0700)
Usage string fix.

* ah/pack-objects-usage-strings:
pack-objects: place angle brackets around placeholders in usage strings

1  2 
builtin/pack-objects.c
diff --combined builtin/pack-objects.c
index 62cc16ddc24320273bba4732c4402e8f6221ab95,06884c2a5722c0d159c6857b0788e8dcbb167799..1c63f8f28c7d925ee5647f190d236e64fc6e05a2
  #include "diff.h"
  #include "revision.h"
  #include "list-objects.h"
 +#include "pack-objects.h"
  #include "progress.h"
  #include "refs.h"
  #include "streaming.h"
  #include "thread-utils.h"
 +#include "pack-bitmap.h"
 +#include "reachable.h"
 +#include "sha1-array.h"
 +#include "argv-array.h"
  
  static const char *pack_usage[] = {
-       N_("git pack-objects --stdout [options...] [< ref-list | < object-list]"),
-       N_("git pack-objects [options...] base-name [< ref-list | < object-list]"),
+       N_("git pack-objects --stdout [<options>...] [< <ref-list> | < <object-list>]"),
+       N_("git pack-objects [<options>...] <base-name> [< <ref-list> | < <object-list>]"),
        NULL
  };
  
 -struct object_entry {
 -      struct pack_idx_entry idx;
 -      unsigned long size;     /* uncompressed size */
 -      struct packed_git *in_pack;     /* already in pack */
 -      off_t in_pack_offset;
 -      struct object_entry *delta;     /* delta base object */
 -      struct object_entry *delta_child; /* deltified objects who bases me */
 -      struct object_entry *delta_sibling; /* other deltified objects who
 -                                           * uses the same base as me
 -                                           */
 -      void *delta_data;       /* cached delta (uncompressed) */
 -      unsigned long delta_size;       /* delta data size (uncompressed) */
 -      unsigned long z_delta_size;     /* delta data size (compressed) */
 -      unsigned int hash;      /* name hint hash */
 -      enum object_type type;
 -      enum object_type in_pack_type;  /* could be delta */
 -      unsigned char in_pack_header_size;
 -      unsigned char preferred_base; /* we do not pack this, but is available
 -                                     * to be used as the base object to delta
 -                                     * objects against.
 -                                     */
 -      unsigned char no_try_delta;
 -      unsigned char tagged; /* near the very tip of refs */
 -      unsigned char filled; /* assigned write-order */
 -};
 -
  /*
 - * Objects we are going to pack are collected in objects array (dynamically
 - * expanded).  nr_objects & nr_alloc controls this array.  They are stored
 - * in the order we see -- typically rev-list --objects order that gives us
 - * nice "minimum seek" order.
 + * Objects we are going to pack are collected in the `to_pack` structure.
 + * It contains an array (dynamically expanded) of the object data, and a map
 + * that can resolve SHA1s to their position in the array.
   */
 -static struct object_entry *objects;
 +static struct packing_data to_pack;
 +
  static struct pack_idx_entry **written_list;
 -static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
 +static uint32_t nr_result, nr_written;
  
  static int non_empty;
  static int reuse_delta = 1, reuse_object = 1;
@@@ -61,42 -82,27 +61,42 @@@ static struct progress *progress_state
  static int pack_compression_level = Z_DEFAULT_COMPRESSION;
  static int pack_compression_seen;
  
 +static struct packed_git *reuse_packfile;
 +static uint32_t reuse_packfile_objects;
 +static off_t reuse_packfile_offset;
 +
 +static int use_bitmap_index = 1;
 +static int write_bitmap_index;
 +static uint16_t write_bitmap_options;
 +
  static unsigned long delta_cache_size = 0;
  static unsigned long max_delta_cache_size = 256 * 1024 * 1024;
  static unsigned long cache_max_small_delta_size = 1000;
  
  static unsigned long window_memory_limit = 0;
  
 -/*
 - * The object names in objects array are hashed with this hashtable,
 - * to help looking up the entry by object name.
 - * This hashtable is built after all the objects are seen.
 - */
 -static int *object_ix;
 -static int object_ix_hashsz;
 -static struct object_entry *locate_object_entry(const unsigned char *sha1);
 -
  /*
   * stats
   */
  static uint32_t written, written_delta;
  static uint32_t reused, reused_delta;
  
 +/*
 + * Indexed commits
 + */
 +static struct commit **indexed_commits;
 +static unsigned int indexed_commits_nr;
 +static unsigned int indexed_commits_alloc;
 +
 +static void index_commit_for_bitmap(struct commit *commit)
 +{
 +      if (indexed_commits_nr >= indexed_commits_alloc) {
 +              indexed_commits_alloc = (indexed_commits_alloc + 32) * 2;
 +              REALLOC_ARRAY(indexed_commits, indexed_commits_alloc);
 +      }
 +
 +      indexed_commits[indexed_commits_nr++] = commit;
 +}
  
  static void *get_delta(struct object_entry *entry)
  {
@@@ -125,6 -131,7 +125,6 @@@ static unsigned long do_compress(void *
        void *in, *out;
        unsigned long maxsize;
  
 -      memset(&stream, 0, sizeof(stream));
        git_deflate_init(&stream, pack_compression_level);
        maxsize = git_deflate_bound(&stream, size);
  
@@@ -152,6 -159,7 +152,6 @@@ static unsigned long write_large_blob_d
        unsigned char obuf[1024 * 16];
        unsigned long olen = 0;
  
 -      memset(&stream, 0, sizeof(stream));
        git_deflate_init(&stream, pack_compression_level);
  
        for (;;) {
@@@ -540,16 -548,16 +540,16 @@@ static enum write_one_status write_one(
        return WRITE_ONE_WRITTEN;
  }
  
 -static int mark_tagged(const char *path, const unsigned char *sha1, int flag,
 +static int mark_tagged(const char *path, const struct object_id *oid, int flag,
                       void *cb_data)
  {
        unsigned char peeled[20];
 -      struct object_entry *entry = locate_object_entry(sha1);
 +      struct object_entry *entry = packlist_find(&to_pack, oid->hash, NULL);
  
        if (entry)
                entry->tagged = 1;
        if (!peel_ref(path, peeled)) {
 -              entry = locate_object_entry(peeled);
 +              entry = packlist_find(&to_pack, peeled, NULL);
                if (entry)
                        entry->tagged = 1;
        }
@@@ -624,10 -632,9 +624,10 @@@ static struct object_entry **compute_wr
  {
        unsigned int i, wo_end, last_untagged;
  
 -      struct object_entry **wo = xmalloc(nr_objects * sizeof(*wo));
 +      struct object_entry **wo = xmalloc(to_pack.nr_objects * sizeof(*wo));
 +      struct object_entry *objects = to_pack.objects;
  
 -      for (i = 0; i < nr_objects; i++) {
 +      for (i = 0; i < to_pack.nr_objects; i++) {
                objects[i].tagged = 0;
                objects[i].filled = 0;
                objects[i].delta_child = NULL;
         * Make sure delta_sibling is sorted in the original
         * recency order.
         */
 -      for (i = nr_objects; i > 0;) {
 +      for (i = to_pack.nr_objects; i > 0;) {
                struct object_entry *e = &objects[--i];
                if (!e->delta)
                        continue;
         * Give the objects in the original recency order until
         * we see a tagged tip.
         */
 -      for (i = wo_end = 0; i < nr_objects; i++) {
 +      for (i = wo_end = 0; i < to_pack.nr_objects; i++) {
                if (objects[i].tagged)
                        break;
                add_to_write_order(wo, &wo_end, &objects[i]);
        /*
         * Then fill all the tagged tips.
         */
 -      for (; i < nr_objects; i++) {
 +      for (; i < to_pack.nr_objects; i++) {
                if (objects[i].tagged)
                        add_to_write_order(wo, &wo_end, &objects[i]);
        }
        /*
         * And then all remaining commits and tags.
         */
 -      for (i = last_untagged; i < nr_objects; i++) {
 +      for (i = last_untagged; i < to_pack.nr_objects; i++) {
                if (objects[i].type != OBJ_COMMIT &&
                    objects[i].type != OBJ_TAG)
                        continue;
        /*
         * And then all the trees.
         */
 -      for (i = last_untagged; i < nr_objects; i++) {
 +      for (i = last_untagged; i < to_pack.nr_objects; i++) {
                if (objects[i].type != OBJ_TREE)
                        continue;
                add_to_write_order(wo, &wo_end, &objects[i]);
        /*
         * Finally all the rest in really tight order
         */
 -      for (i = last_untagged; i < nr_objects; i++) {
 +      for (i = last_untagged; i < to_pack.nr_objects; i++) {
                if (!objects[i].filled)
                        add_family_to_write_order(wo, &wo_end, &objects[i]);
        }
  
 -      if (wo_end != nr_objects)
 -              die("ordered %u objects, expected %"PRIu32, wo_end, nr_objects);
 +      if (wo_end != to_pack.nr_objects)
 +              die("ordered %u objects, expected %"PRIu32, wo_end, to_pack.nr_objects);
  
        return wo;
  }
  
 +static off_t write_reused_pack(struct sha1file *f)
 +{
 +      unsigned char buffer[8192];
 +      off_t to_write, total;
 +      int fd;
 +
 +      if (!is_pack_valid(reuse_packfile))
 +              die("packfile is invalid: %s", reuse_packfile->pack_name);
 +
 +      fd = git_open_noatime(reuse_packfile->pack_name);
 +      if (fd < 0)
 +              die_errno("unable to open packfile for reuse: %s",
 +                        reuse_packfile->pack_name);
 +
 +      if (lseek(fd, sizeof(struct pack_header), SEEK_SET) == -1)
 +              die_errno("unable to seek in reused packfile");
 +
 +      if (reuse_packfile_offset < 0)
 +              reuse_packfile_offset = reuse_packfile->pack_size - 20;
 +
 +      total = to_write = reuse_packfile_offset - sizeof(struct pack_header);
 +
 +      while (to_write) {
 +              int read_pack = xread(fd, buffer, sizeof(buffer));
 +
 +              if (read_pack <= 0)
 +                      die_errno("unable to read from reused packfile");
 +
 +              if (read_pack > to_write)
 +                      read_pack = to_write;
 +
 +              sha1write(f, buffer, read_pack);
 +              to_write -= read_pack;
 +
 +              /*
 +               * We don't know the actual number of objects written,
 +               * only how many bytes written, how many bytes total, and
 +               * how many objects total. So we can fake it by pretending all
 +               * objects we are writing are the same size. This gives us a
 +               * smooth progress meter, and at the end it matches the true
 +               * answer.
 +               */
 +              written = reuse_packfile_objects *
 +                              (((double)(total - to_write)) / total);
 +              display_progress(progress_state, written);
 +      }
 +
 +      close(fd);
 +      written = reuse_packfile_objects;
 +      display_progress(progress_state, written);
 +      return reuse_packfile_offset - sizeof(struct pack_header);
 +}
 +
  static void write_pack_file(void)
  {
        uint32_t i = 0, j;
        struct object_entry **write_order;
  
        if (progress > pack_to_stdout)
 -              progress_state = start_progress("Writing objects", nr_result);
 -      written_list = xmalloc(nr_objects * sizeof(*written_list));
 +              progress_state = start_progress(_("Writing objects"), nr_result);
 +      written_list = xmalloc(to_pack.nr_objects * sizeof(*written_list));
        write_order = compute_write_order();
  
        do {
                        f = create_tmp_packfile(&pack_tmp_name);
  
                offset = write_pack_header(f, nr_remaining);
 -              if (!offset)
 -                      die_errno("unable to write pack header");
 +
 +              if (reuse_packfile) {
 +                      off_t packfile_size;
 +                      assert(pack_to_stdout);
 +
 +                      packfile_size = write_reused_pack(f);
 +                      offset += packfile_size;
 +              }
 +
                nr_written = 0;
 -              for (; i < nr_objects; i++) {
 +              for (; i < to_pack.nr_objects; i++) {
                        struct object_entry *e = write_order[i];
                        if (write_one(f, e, &offset) == WRITE_ONE_BREAK)
                                break;
                        fixup_pack_header_footer(fd, sha1, pack_tmp_name,
                                                 nr_written, sha1, offset);
                        close(fd);
 +                      write_bitmap_index = 0;
                }
  
                if (!pack_to_stdout) {
                        struct stat st;
 -                      char tmpname[PATH_MAX];
 +                      struct strbuf tmpname = STRBUF_INIT;
  
                        /*
                         * Packs are runtime accessed in their mtime
                                utb.modtime = --last_mtime;
                                if (utime(pack_tmp_name, &utb) < 0)
                                        warning("failed utime() on %s: %s",
 -                                              tmpname, strerror(errno));
 +                                              pack_tmp_name, strerror(errno));
 +                      }
 +
 +                      strbuf_addf(&tmpname, "%s-", base_name);
 +
 +                      if (write_bitmap_index) {
 +                              bitmap_writer_set_checksum(sha1);
 +                              bitmap_writer_build_type_index(written_list, nr_written);
                        }
  
 -                      /* Enough space for "-<sha-1>.pack"? */
 -                      if (sizeof(tmpname) <= strlen(base_name) + 50)
 -                              die("pack base name '%s' too long", base_name);
 -                      snprintf(tmpname, sizeof(tmpname), "%s-", base_name);
 -                      finish_tmp_packfile(tmpname, pack_tmp_name,
 +                      finish_tmp_packfile(&tmpname, pack_tmp_name,
                                            written_list, nr_written,
                                            &pack_idx_opts, sha1);
 +
 +                      if (write_bitmap_index) {
 +                              strbuf_addf(&tmpname, "%s.bitmap", sha1_to_hex(sha1));
 +
 +                              stop_progress(&progress_state);
 +
 +                              bitmap_writer_show_progress(progress);
 +                              bitmap_writer_reuse_bitmaps(&to_pack);
 +                              bitmap_writer_select_commits(indexed_commits, indexed_commits_nr, -1);
 +                              bitmap_writer_build(&to_pack);
 +                              bitmap_writer_finish(written_list, nr_written,
 +                                                   tmpname.buf, write_bitmap_options);
 +                              write_bitmap_index = 0;
 +                      }
 +
 +                      strbuf_release(&tmpname);
                        free(pack_tmp_name);
                        puts(sha1_to_hex(sha1));
                }
                        written_list[j]->offset = (off_t)-1;
                }
                nr_remaining -= nr_written;
 -      } while (nr_remaining && i < nr_objects);
 +      } while (nr_remaining && i < to_pack.nr_objects);
  
        free(written_list);
        free(write_order);
                        written, nr_result);
  }
  
 -static int locate_object_entry_hash(const unsigned char *sha1)
 -{
 -      int i;
 -      unsigned int ui;
 -      memcpy(&ui, sha1, sizeof(unsigned int));
 -      i = ui % object_ix_hashsz;
 -      while (0 < object_ix[i]) {
 -              if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
 -                      return i;
 -              if (++i == object_ix_hashsz)
 -                      i = 0;
 -      }
 -      return -1 - i;
 -}
 -
 -static struct object_entry *locate_object_entry(const unsigned char *sha1)
 -{
 -      int i;
 -
 -      if (!object_ix_hashsz)
 -              return NULL;
 -
 -      i = locate_object_entry_hash(sha1);
 -      if (0 <= i)
 -              return &objects[object_ix[i]-1];
 -      return NULL;
 -}
 -
 -static void rehash_objects(void)
 -{
 -      uint32_t i;
 -      struct object_entry *oe;
 -
 -      object_ix_hashsz = nr_objects * 3;
 -      if (object_ix_hashsz < 1024)
 -              object_ix_hashsz = 1024;
 -      object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
 -      memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
 -      for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
 -              int ix = locate_object_entry_hash(oe->idx.sha1);
 -              if (0 <= ix)
 -                      continue;
 -              ix = -1 - ix;
 -              object_ix[ix] = i + 1;
 -      }
 -}
 -
 -static unsigned name_hash(const char *name)
 -{
 -      unsigned c, hash = 0;
 -
 -      if (!name)
 -              return 0;
 -
 -      /*
 -       * This effectively just creates a sortable number from the
 -       * last sixteen non-whitespace characters. Last characters
 -       * count "most", so things that end in ".c" sort together.
 -       */
 -      while ((c = *name++) != 0) {
 -              if (isspace(c))
 -                      continue;
 -              hash = (hash >> 2) + (c << 24);
 -      }
 -      return hash;
 -}
 -
  static void setup_delta_attr_check(struct git_attr_check *check)
  {
        static struct git_attr *attr_delta;
@@@ -907,67 -901,42 +907,67 @@@ static int no_try_delta(const char *pat
        return 0;
  }
  
 -static int add_object_entry(const unsigned char *sha1, enum object_type type,
 -                          const char *name, int exclude)
 +/*
 + * When adding an object, check whether we have already added it
 + * to our packing list. If so, we can skip. However, if we are
 + * being asked to excludei t, but the previous mention was to include
 + * it, make sure to adjust its flags and tweak our numbers accordingly.
 + *
 + * As an optimization, we pass out the index position where we would have
 + * found the item, since that saves us from having to look it up again a
 + * few lines later when we want to add the new entry.
 + */
 +static int have_duplicate_entry(const unsigned char *sha1,
 +                              int exclude,
 +                              uint32_t *index_pos)
  {
        struct object_entry *entry;
 -      struct packed_git *p, *found_pack = NULL;
 -      off_t found_offset = 0;
 -      int ix;
 -      unsigned hash = name_hash(name);
 -
 -      ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
 -      if (ix >= 0) {
 -              if (exclude) {
 -                      entry = objects + object_ix[ix] - 1;
 -                      if (!entry->preferred_base)
 -                              nr_result--;
 -                      entry->preferred_base = 1;
 -              }
 +
 +      entry = packlist_find(&to_pack, sha1, index_pos);
 +      if (!entry)
                return 0;
 +
 +      if (exclude) {
 +              if (!entry->preferred_base)
 +                      nr_result--;
 +              entry->preferred_base = 1;
        }
  
 +      return 1;
 +}
 +
 +/*
 + * Check whether we want the object in the pack (e.g., we do not want
 + * objects found in non-local stores if the "--local" option was used).
 + *
 + * As a side effect of this check, we will find the packed version of this
 + * object, if any. We therefore pass out the pack information to avoid having
 + * to look it up again later.
 + */
 +static int want_object_in_pack(const unsigned char *sha1,
 +                             int exclude,
 +                             struct packed_git **found_pack,
 +                             off_t *found_offset)
 +{
 +      struct packed_git *p;
 +
        if (!exclude && local && has_loose_object_nonlocal(sha1))
                return 0;
  
 +      *found_pack = NULL;
 +      *found_offset = 0;
 +
        for (p = packed_git; p; p = p->next) {
                off_t offset = find_pack_entry_one(sha1, p);
                if (offset) {
 -                      if (!found_pack) {
 -                              if (!is_pack_valid(p)) {
 -                                      warning("packfile %s cannot be accessed", p->pack_name);
 +                      if (!*found_pack) {
 +                              if (!is_pack_valid(p))
                                        continue;
 -                              }
 -                              found_offset = offset;
 -                              found_pack = p;
 +                              *found_offset = offset;
 +                              *found_pack = p;
                        }
                        if (exclude)
 -                              break;
 +                              return 1;
                        if (incremental)
                                return 0;
                        if (local && !p->pack_local)
                }
        }
  
 -      if (nr_objects >= nr_alloc) {
 -              nr_alloc = (nr_alloc  + 1024) * 3 / 2;
 -              objects = xrealloc(objects, nr_alloc * sizeof(*entry));
 -      }
 +      return 1;
 +}
 +
 +static void create_object_entry(const unsigned char *sha1,
 +                              enum object_type type,
 +                              uint32_t hash,
 +                              int exclude,
 +                              int no_try_delta,
 +                              uint32_t index_pos,
 +                              struct packed_git *found_pack,
 +                              off_t found_offset)
 +{
 +      struct object_entry *entry;
  
 -      entry = objects + nr_objects++;
 -      memset(entry, 0, sizeof(*entry));
 -      hashcpy(entry->idx.sha1, sha1);
 +      entry = packlist_alloc(&to_pack, sha1, index_pos);
        entry->hash = hash;
        if (type)
                entry->type = type;
                entry->in_pack_offset = found_offset;
        }
  
 -      if (object_ix_hashsz * 3 <= nr_objects * 4)
 -              rehash_objects();
 -      else
 -              object_ix[-1 - ix] = nr_objects;
 +      entry->no_try_delta = no_try_delta;
 +}
 +
 +static const char no_closure_warning[] = N_(
 +"disabling bitmap writing, as some objects are not being packed"
 +);
 +
 +static int add_object_entry(const unsigned char *sha1, enum object_type type,
 +                          const char *name, int exclude)
 +{
 +      struct packed_git *found_pack;
 +      off_t found_offset;
 +      uint32_t index_pos;
 +
 +      if (have_duplicate_entry(sha1, exclude, &index_pos))
 +              return 0;
 +
 +      if (!want_object_in_pack(sha1, exclude, &found_pack, &found_offset)) {
 +              /* The pack is missing an object, so it will not have closure */
 +              if (write_bitmap_index) {
 +                      warning(_(no_closure_warning));
 +                      write_bitmap_index = 0;
 +              }
 +              return 0;
 +      }
 +
 +      create_object_entry(sha1, type, pack_name_hash(name),
 +                          exclude, name && no_try_delta(name),
 +                          index_pos, found_pack, found_offset);
 +
 +      display_progress(progress_state, nr_result);
 +      return 1;
 +}
 +
 +static int add_object_entry_from_bitmap(const unsigned char *sha1,
 +                                      enum object_type type,
 +                                      int flags, uint32_t name_hash,
 +                                      struct packed_git *pack, off_t offset)
 +{
 +      uint32_t index_pos;
  
 -      display_progress(progress_state, nr_objects);
 +      if (have_duplicate_entry(sha1, 0, &index_pos))
 +              return 0;
  
 -      if (name && no_try_delta(name))
 -              entry->no_try_delta = 1;
 +      create_object_entry(sha1, type, name_hash, 0, 0, index_pos, pack, offset);
  
 +      display_progress(progress_state, nr_result);
        return 1;
  }
  
@@@ -1075,7 -1000,7 +1075,7 @@@ static int pbase_tree_cache_ix_incr(in
  static struct pbase_tree {
        struct pbase_tree *next;
        /* This is a phony "cache" entry; we are not
 -       * going to evict it nor find it through _get()
 +       * going to evict it or find it through _get()
         * mechanism -- this is for the toplevel node that
         * would almost always change with any commit.
         */
@@@ -1232,9 -1157,12 +1232,9 @@@ static int check_pbase_path(unsigned ha
        if (0 <= pos)
                return 1;
        pos = -pos - 1;
 -      if (done_pbase_paths_alloc <= done_pbase_paths_num) {
 -              done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
 -              done_pbase_paths = xrealloc(done_pbase_paths,
 -                                          done_pbase_paths_alloc *
 -                                          sizeof(unsigned));
 -      }
 +      ALLOC_GROW(done_pbase_paths,
 +                 done_pbase_paths_num + 1,
 +                 done_pbase_paths_alloc);
        done_pbase_paths_num++;
        if (pos < done_pbase_paths_num)
                memmove(done_pbase_paths + pos + 1,
@@@ -1248,7 -1176,7 +1248,7 @@@ static void add_preferred_base_object(c
  {
        struct pbase_tree *it;
        int cmplen;
 -      unsigned hash = name_hash(name);
 +      unsigned hash = pack_name_hash(name);
  
        if (!num_preferred_base || check_pbase_path(hash))
                return;
@@@ -1400,7 -1328,7 +1400,7 @@@ static void check_object(struct object_
                        break;
                }
  
 -              if (base_ref && (base_entry = locate_object_entry(base_ref))) {
 +              if (base_ref && (base_entry = packlist_find(&to_pack, base_ref, NULL))) {
                        /*
                         * If base_ref was set above that means we wish to
                         * reuse delta data, and we even found that base
@@@ -1474,12 -1402,12 +1474,12 @@@ static void get_object_details(void
        uint32_t i;
        struct object_entry **sorted_by_offset;
  
 -      sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
 -      for (i = 0; i < nr_objects; i++)
 -              sorted_by_offset[i] = objects + i;
 -      qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
 +      sorted_by_offset = xcalloc(to_pack.nr_objects, sizeof(struct object_entry *));
 +      for (i = 0; i < to_pack.nr_objects; i++)
 +              sorted_by_offset[i] = to_pack.objects + i;
 +      qsort(sorted_by_offset, to_pack.nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
  
 -      for (i = 0; i < nr_objects; i++) {
 +      for (i = 0; i < to_pack.nr_objects; i++) {
                struct object_entry *entry = sorted_by_offset[i];
                check_object(entry);
                if (big_file_threshold < entry->size)
@@@ -1881,7 -1809,7 +1881,7 @@@ static void find_deltas(struct object_e
  static void try_to_free_from_threads(size_t size)
  {
        read_lock();
 -      release_pack_memory(size, -1);
 +      release_pack_memory(size);
        read_unlock();
  }
  
@@@ -1972,6 -1900,8 +1972,6 @@@ static void ll_find_deltas(struct objec
  
        init_threaded_search();
  
 -      if (!delta_search_threads)      /* --threads=0 means autodetect */
 -              delta_search_threads = online_cpus();
        if (delta_search_threads <= 1) {
                find_deltas(list, &list_size, window, depth, processed);
                cleanup_threaded_search();
  #define ll_find_deltas(l, s, w, d, p) find_deltas(l, &s, w, d, p)
  #endif
  
 -static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 +static int add_ref_tag(const char *path, const struct object_id *oid, int flag, void *cb_data)
  {
 -      unsigned char peeled[20];
 +      struct object_id peeled;
  
 -      if (!prefixcmp(path, "refs/tags/") && /* is a tag? */
 -          !peel_ref(path, peeled)        && /* peelable? */
 -          !is_null_sha1(peeled)          && /* annotated tag? */
 -          locate_object_entry(peeled))      /* object packed? */
 -              add_object_entry(sha1, OBJ_TAG, NULL, 0);
 +      if (starts_with(path, "refs/tags/") && /* is a tag? */
 +          !peel_ref(path, peeled.hash)    && /* peelable? */
 +          packlist_find(&to_pack, peeled.hash, NULL))      /* object packed? */
 +              add_object_entry(oid->hash, OBJ_TAG, NULL, 0);
        return 0;
  }
  
@@@ -2126,14 -2057,14 +2126,14 @@@ static void prepare_pack(int window, in
        if (!pack_to_stdout)
                do_check_packed_object_crc = 1;
  
 -      if (!nr_objects || !window || !depth)
 +      if (!to_pack.nr_objects || !window || !depth)
                return;
  
 -      delta_list = xmalloc(nr_objects * sizeof(*delta_list));
 +      delta_list = xmalloc(to_pack.nr_objects * sizeof(*delta_list));
        nr_deltas = n = 0;
  
 -      for (i = 0; i < nr_objects; i++) {
 -              struct object_entry *entry = objects + i;
 +      for (i = 0; i < to_pack.nr_objects; i++) {
 +              struct object_entry *entry = to_pack.objects + i;
  
                if (entry->delta)
                        /* This happens if we decided to reuse existing
        if (nr_deltas && n > 1) {
                unsigned nr_done = 0;
                if (progress)
 -                      progress_state = start_progress("Compressing objects",
 +                      progress_state = start_progress(_("Compressing objects"),
                                                        nr_deltas);
                qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
                ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
@@@ -2211,16 -2142,6 +2211,16 @@@ static int git_pack_config(const char *
                cache_max_small_delta_size = git_config_int(k, v);
                return 0;
        }
 +      if (!strcmp(k, "pack.writebitmaphashcache")) {
 +              if (git_config_bool(k, v))
 +                      write_bitmap_options |= BITMAP_OPT_HASH_CACHE;
 +              else
 +                      write_bitmap_options &= ~BITMAP_OPT_HASH_CACHE;
 +      }
 +      if (!strcmp(k, "pack.usebitmaps")) {
 +              use_bitmap_index = git_config_bool(k, v);
 +              return 0;
 +      }
        if (!strcmp(k, "pack.threads")) {
                delta_search_threads = git_config_int(k, v);
                if (delta_search_threads < 0)
@@@ -2279,9 -2200,6 +2279,9 @@@ static void show_commit(struct commit *
  {
        add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
        commit->object.flags |= OBJECT_ADDED;
 +
 +      if (write_bitmap_index)
 +              index_commit_for_bitmap(commit);
  }
  
  static void show_object(struct object *obj,
@@@ -2405,27 -2323,6 +2405,27 @@@ static int has_sha1_pack_kept_or_nonloc
        return 0;
  }
  
 +/*
 + * Store a list of sha1s that are should not be discarded
 + * because they are either written too recently, or are
 + * reachable from another object that was.
 + *
 + * This is filled by get_object_list.
 + */
 +static struct sha1_array recent_objects;
 +
 +static int loosened_object_can_be_discarded(const unsigned char *sha1,
 +                                          unsigned long mtime)
 +{
 +      if (!unpack_unreachable_expiration)
 +              return 0;
 +      if (mtime > unpack_unreachable_expiration)
 +              return 0;
 +      if (sha1_array_lookup(&recent_objects, sha1) >= 0)
 +              return 0;
 +      return 1;
 +}
 +
  static void loosen_unused_packed_objects(struct rev_info *revs)
  {
        struct packed_git *p;
                if (!p->pack_local || p->pack_keep)
                        continue;
  
 -              if (unpack_unreachable_expiration &&
 -                  p->mtime < unpack_unreachable_expiration)
 -                      continue;
 -
                if (open_pack_index(p))
                        die("cannot open pack index");
  
                for (i = 0; i < p->num_objects; i++) {
                        sha1 = nth_packed_object_sha1(p, i);
 -                      if (!locate_object_entry(sha1) &&
 -                              !has_sha1_pack_kept_or_nonlocal(sha1))
 +                      if (!packlist_find(&to_pack, sha1, NULL) &&
 +                          !has_sha1_pack_kept_or_nonlocal(sha1) &&
 +                          !loosened_object_can_be_discarded(sha1, p->mtime))
                                if (force_object_loose(sha1, p->mtime))
                                        die("unable to force loose object");
                }
        }
  }
  
 +/*
 + * This tracks any options which a reader of the pack might
 + * not understand, and which would therefore prevent blind reuse
 + * of what we have on disk.
 + */
 +static int pack_options_allow_reuse(void)
 +{
 +      return allow_ofs_delta;
 +}
 +
 +static int get_object_list_from_bitmap(struct rev_info *revs)
 +{
 +      if (prepare_bitmap_walk(revs) < 0)
 +              return -1;
 +
 +      if (pack_options_allow_reuse() &&
 +          !reuse_partial_packfile_from_bitmap(
 +                      &reuse_packfile,
 +                      &reuse_packfile_objects,
 +                      &reuse_packfile_offset)) {
 +              assert(reuse_packfile_objects);
 +              nr_result += reuse_packfile_objects;
 +              display_progress(progress_state, nr_result);
 +      }
 +
 +      traverse_bitmap_commit_list(&add_object_entry_from_bitmap);
 +      return 0;
 +}
 +
 +static void record_recent_object(struct object *obj,
 +                               const struct name_path *path,
 +                               const char *last,
 +                               void *data)
 +{
 +      sha1_array_append(&recent_objects, obj->sha1);
 +}
 +
 +static void record_recent_commit(struct commit *commit, void *data)
 +{
 +      sha1_array_append(&recent_objects, commit->object.sha1);
 +}
 +
  static void get_object_list(int ac, const char **av)
  {
        struct rev_info revs;
        save_commit_buffer = 0;
        setup_revisions(ac, av, &revs, NULL);
  
 +      /* make sure shallows are read */
 +      is_repository_shallow();
 +
        while (fgets(line, sizeof(line), stdin) != NULL) {
                int len = strlen(line);
                if (len && line[len - 1] == '\n')
                if (*line == '-') {
                        if (!strcmp(line, "--not")) {
                                flags ^= UNINTERESTING;
 +                              write_bitmap_index = 0;
 +                              continue;
 +                      }
 +                      if (starts_with(line, "--shallow ")) {
 +                              unsigned char sha1[20];
 +                              if (get_sha1_hex(line + 10, sha1))
 +                                      die("not an SHA-1 '%s'", line + 10);
 +                              register_shallow(sha1);
 +                              use_bitmap_index = 0;
                                continue;
                        }
                        die("not a rev '%s'", line);
                        die("bad revision '%s'", line);
        }
  
 +      if (use_bitmap_index && !get_object_list_from_bitmap(&revs))
 +              return;
 +
        if (prepare_revision_walk(&revs))
                die("revision walk setup failed");
 -      mark_edges_uninteresting(revs.commits, &revs, show_edge);
 +      mark_edges_uninteresting(&revs, show_edge);
        traverse_commit_list(&revs, show_commit, show_object, NULL);
  
 +      if (unpack_unreachable_expiration) {
 +              revs.ignore_missing_links = 1;
 +              if (add_unseen_recent_objects_to_traversal(&revs,
 +                              unpack_unreachable_expiration))
 +                      die("unable to add recent objects");
 +              if (prepare_revision_walk(&revs))
 +                      die("revision walk setup failed");
 +              traverse_commit_list(&revs, record_recent_commit,
 +                                   record_recent_object, NULL);
 +      }
 +
        if (keep_unreachable)
                add_objects_in_unpacked_packs(&revs);
        if (unpack_unreachable)
                loosen_unused_packed_objects(&revs);
 +
 +      sha1_array_clear(&recent_objects);
  }
  
  static int option_parse_index_version(const struct option *opt,
@@@ -2588,15 -2418,31 +2588,15 @@@ static int option_parse_unpack_unreacha
        return 0;
  }
  
 -static int option_parse_ulong(const struct option *opt,
 -                            const char *arg, int unset)
 -{
 -      if (unset)
 -              die(_("option %s does not accept negative form"),
 -                  opt->long_name);
 -
 -      if (!git_parse_ulong(arg, opt->value))
 -              die(_("unable to parse value '%s' for option %s"),
 -                  arg, opt->long_name);
 -      return 0;
 -}
 -
 -#define OPT_ULONG(s, l, v, h) \
 -      { OPTION_CALLBACK, (s), (l), (v), "n", (h),     \
 -        PARSE_OPT_NONEG, option_parse_ulong }
 -
  int cmd_pack_objects(int argc, const char **argv, const char *prefix)
  {
        int use_internal_rev_list = 0;
        int thin = 0;
 +      int shallow = 0;
        int all_progress_implied = 0;
 -      const char *rp_av[6];
 -      int rp_ac = 0;
 +      struct argv_array rp = ARGV_ARRAY_INIT;
        int rev_list_unpacked = 0, rev_list_all = 0, rev_list_reflog = 0;
 +      int rev_list_index = 0;
        struct option pack_objects_options[] = {
                OPT_SET_INT('q', "quiet", &progress,
                            N_("do not show progress meter"), 0),
                { OPTION_CALLBACK, 0, "index-version", NULL, N_("version[,offset]"),
                  N_("write the pack index file in the specified idx format version"),
                  0, option_parse_index_version },
 -              OPT_ULONG(0, "max-pack-size", &pack_size_limit,
 -                        N_("maximum size of each output pack file")),
 +              OPT_MAGNITUDE(0, "max-pack-size", &pack_size_limit,
 +                            N_("maximum size of each output pack file")),
                OPT_BOOL(0, "local", &local,
                         N_("ignore borrowed objects from alternate object store")),
                OPT_BOOL(0, "incremental", &incremental,
                         N_("ignore packed objects")),
                OPT_INTEGER(0, "window", &window,
                            N_("limit pack window by objects")),
 -              OPT_ULONG(0, "window-memory", &window_memory_limit,
 -                        N_("limit pack window by memory in addition to object limit")),
 +              OPT_MAGNITUDE(0, "window-memory", &window_memory_limit,
 +                            N_("limit pack window by memory in addition to object limit")),
                OPT_INTEGER(0, "depth", &depth,
                            N_("maximum length of delta chain allowed in the resulting pack")),
                OPT_BOOL(0, "reuse-delta", &reuse_delta,
                { OPTION_SET_INT, 0, "reflog", &rev_list_reflog, NULL,
                  N_("include objects referred by reflog entries"),
                  PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, 1 },
 +              { OPTION_SET_INT, 0, "indexed-objects", &rev_list_index, NULL,
 +                N_("include objects referred to by the index"),
 +                PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL, 1 },
                OPT_BOOL(0, "stdout", &pack_to_stdout,
                         N_("output pack to stdout")),
                OPT_BOOL(0, "include-tag", &include_tag,
                  PARSE_OPT_OPTARG, option_parse_unpack_unreachable },
                OPT_BOOL(0, "thin", &thin,
                         N_("create thin packs")),
 +              OPT_BOOL(0, "shallow", &shallow,
 +                       N_("create packs suitable for shallow fetches")),
                OPT_BOOL(0, "honor-pack-keep", &ignore_packed_keep,
                         N_("ignore packs that have companion .keep file")),
                OPT_INTEGER(0, "compression", &pack_compression_level,
                            N_("pack compression level")),
                OPT_SET_INT(0, "keep-true-parents", &grafts_replace_parents,
                            N_("do not hide commits by grafts"), 0),
 +              OPT_BOOL(0, "use-bitmap-index", &use_bitmap_index,
 +                       N_("use a bitmap index if available to speed up counting objects")),
 +              OPT_BOOL(0, "write-bitmap-index", &write_bitmap_index,
 +                       N_("write a bitmap index together with the pack index")),
                OPT_END(),
        };
  
 -      read_replace_refs = 0;
 +      check_replace_refs = 0;
  
        reset_pack_idx_option(&pack_idx_opts);
        git_config(git_pack_config, NULL);
        if (pack_to_stdout != !base_name || argc)
                usage_with_options(pack_usage, pack_objects_options);
  
 -      rp_av[rp_ac++] = "pack-objects";
 +      argv_array_push(&rp, "pack-objects");
        if (thin) {
                use_internal_rev_list = 1;
 -              rp_av[rp_ac++] = "--objects-edge";
 +              argv_array_push(&rp, shallow
 +                              ? "--objects-edge-aggressive"
 +                              : "--objects-edge");
        } else
 -              rp_av[rp_ac++] = "--objects";
 +              argv_array_push(&rp, "--objects");
  
        if (rev_list_all) {
                use_internal_rev_list = 1;
 -              rp_av[rp_ac++] = "--all";
 +              argv_array_push(&rp, "--all");
        }
        if (rev_list_reflog) {
                use_internal_rev_list = 1;
 -              rp_av[rp_ac++] = "--reflog";
 +              argv_array_push(&rp, "--reflog");
 +      }
 +      if (rev_list_index) {
 +              use_internal_rev_list = 1;
 +              argv_array_push(&rp, "--indexed-objects");
        }
        if (rev_list_unpacked) {
                use_internal_rev_list = 1;
 -              rp_av[rp_ac++] = "--unpacked";
 +              argv_array_push(&rp, "--unpacked");
        }
  
        if (!reuse_object)
                pack_compression_level = Z_DEFAULT_COMPRESSION;
        else if (pack_compression_level < 0 || pack_compression_level > Z_BEST_COMPRESSION)
                die("bad pack compression level %d", pack_compression_level);
 +
 +      if (!delta_search_threads)      /* --threads=0 means autodetect */
 +              delta_search_threads = online_cpus();
 +
  #ifdef NO_PTHREADS
        if (delta_search_threads != 1)
                warning("no threads support, ignoring --threads");
  
        if (keep_unreachable && unpack_unreachable)
                die("--keep-unreachable and --unpack-unreachable are incompatible.");
 +      if (!rev_list_all || !rev_list_reflog || !rev_list_index)
 +              unpack_unreachable_expiration = 0;
 +
 +      if (!use_internal_rev_list || !pack_to_stdout || is_repository_shallow())
 +              use_bitmap_index = 0;
 +
 +      if (pack_to_stdout || !rev_list_all)
 +              write_bitmap_index = 0;
  
        if (progress && all_progress_implied)
                progress = 2;
        prepare_packed_git();
  
        if (progress)
 -              progress_state = start_progress("Counting objects", 0);
 +              progress_state = start_progress(_("Counting objects"), 0);
        if (!use_internal_rev_list)
                read_object_list_from_stdin();
        else {
 -              rp_av[rp_ac] = NULL;
 -              get_object_list(rp_ac, rp_av);
 +              get_object_list(rp.argc, rp.argv);
 +              argv_array_clear(&rp);
        }
        cleanup_preferred_base();
        if (include_tag && nr_result)