p5551: add a script to test fetch pack-dir rescans
[gitweb.git] / builtin / pack-objects.c
index 0954375be9ea5fe2b416d4142b6987ff2b5ec94f..3af63ad54cdd4230e9d9eebe3ffd528b5f00551f 100644 (file)
@@ -1,5 +1,6 @@
 #include "builtin.h"
 #include "cache.h"
+#include "config.h"
 #include "attr.h"
 #include "object.h"
 #include "blob.h"
@@ -23,6 +24,7 @@
 #include "reachable.h"
 #include "sha1-array.h"
 #include "argv-array.h"
+#include "mru.h"
 
 static const char *pack_usage[] = {
        N_("git pack-objects --stdout [<options>...] [< <ref-list> | < <object-list>]"),
@@ -43,7 +45,7 @@ static uint32_t nr_result, nr_written;
 static int non_empty;
 static int reuse_delta = 1, reuse_object = 1;
 static int keep_unreachable, unpack_unreachable, include_tag;
-static unsigned long unpack_unreachable_expiration;
+static timestamp_t unpack_unreachable_expiration;
 static int pack_loose_unreachable;
 static int local;
 static int have_non_local_packs;
@@ -60,14 +62,13 @@ static int delta_search_threads;
 static int pack_to_stdout;
 static int num_preferred_base;
 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 use_bitmap_index_default = 1;
+static int use_bitmap_index = -1;
 static int write_bitmap_index;
 static uint16_t write_bitmap_options;
 
@@ -106,12 +107,14 @@ static void *get_delta(struct object_entry *entry)
        void *buf, *base_buf, *delta_buf;
        enum object_type type;
 
-       buf = read_sha1_file(entry->idx.sha1, &type, &size);
+       buf = read_sha1_file(entry->idx.oid.hash, &type, &size);
        if (!buf)
-               die("unable to read %s", sha1_to_hex(entry->idx.sha1));
-       base_buf = read_sha1_file(entry->delta->idx.sha1, &type, &base_size);
+               die("unable to read %s", oid_to_hex(&entry->idx.oid));
+       base_buf = read_sha1_file(entry->delta->idx.oid.hash, &type,
+                                 &base_size);
        if (!base_buf)
-               die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
+               die("unable to read %s",
+                   oid_to_hex(&entry->delta->idx.oid));
        delta_buf = diff_delta(base_buf, base_size,
                               buf, size, &delta_size, 0);
        if (!delta_buf || delta_size != entry->delta_size)
@@ -239,7 +242,8 @@ static unsigned long write_no_reuse_object(struct sha1file *f, struct object_ent
                                           unsigned long limit, int usable_delta)
 {
        unsigned long size, datalen;
-       unsigned char header[10], dheader[10];
+       unsigned char header[MAX_PACK_OBJECT_HEADER],
+                     dheader[MAX_PACK_OBJECT_HEADER];
        unsigned hdrlen;
        enum object_type type;
        void *buf;
@@ -248,19 +252,20 @@ static unsigned long write_no_reuse_object(struct sha1file *f, struct object_ent
        if (!usable_delta) {
                if (entry->type == OBJ_BLOB &&
                    entry->size > big_file_threshold &&
-                   (st = open_istream(entry->idx.sha1, &type, &size, NULL)) != NULL)
+                   (st = open_istream(entry->idx.oid.hash, &type, &size, NULL)) != NULL)
                        buf = NULL;
                else {
-                       buf = read_sha1_file(entry->idx.sha1, &type, &size);
+                       buf = read_sha1_file(entry->idx.oid.hash, &type,
+                                            &size);
                        if (!buf)
-                               die(_("unable to read %s"), sha1_to_hex(entry->idx.sha1));
+                               die(_("unable to read %s"),
+                                   oid_to_hex(&entry->idx.oid));
                }
                /*
                 * make sure no cached delta data remains from a
                 * previous attempt before a pack split occurred.
                 */
-               free(entry->delta_data);
-               entry->delta_data = NULL;
+               FREE_AND_NULL(entry->delta_data);
                entry->z_delta_size = 0;
        } else if (entry->delta_data) {
                size = entry->delta_size;
@@ -286,7 +291,8 @@ static unsigned long write_no_reuse_object(struct sha1file *f, struct object_ent
         * The object header is a byte of 'type' followed by zero or
         * more bytes of length.
         */
-       hdrlen = encode_in_pack_object_header(type, size, header);
+       hdrlen = encode_in_pack_object_header(header, sizeof(header),
+                                             type, size);
 
        if (type == OBJ_OFS_DELTA) {
                /*
@@ -320,7 +326,7 @@ static unsigned long write_no_reuse_object(struct sha1file *f, struct object_ent
                        return 0;
                }
                sha1write(f, header, hdrlen);
-               sha1write(f, entry->delta->idx.sha1, 20);
+               sha1write(f, entry->delta->idx.oid.hash, 20);
                hdrlen += 20;
        } else {
                if (limit && hdrlen + datalen + 20 >= limit) {
@@ -332,7 +338,7 @@ static unsigned long write_no_reuse_object(struct sha1file *f, struct object_ent
                sha1write(f, header, hdrlen);
        }
        if (st) {
-               datalen = write_large_blob_data(st, f, entry->idx.sha1);
+               datalen = write_large_blob_data(st, f, entry->idx.oid.hash);
                close_istream(st);
        } else {
                sha1write(f, buf, datalen);
@@ -352,20 +358,23 @@ static off_t write_reuse_object(struct sha1file *f, struct object_entry *entry,
        off_t offset;
        enum object_type type = entry->type;
        off_t datalen;
-       unsigned char header[10], dheader[10];
+       unsigned char header[MAX_PACK_OBJECT_HEADER],
+                     dheader[MAX_PACK_OBJECT_HEADER];
        unsigned hdrlen;
 
        if (entry->delta)
                type = (allow_ofs_delta && entry->delta->idx.offset) ?
                        OBJ_OFS_DELTA : OBJ_REF_DELTA;
-       hdrlen = encode_in_pack_object_header(type, entry->size, header);
+       hdrlen = encode_in_pack_object_header(header, sizeof(header),
+                                             type, entry->size);
 
        offset = entry->in_pack_offset;
        revidx = find_pack_revindex(p, offset);
        datalen = revidx[1].offset - offset;
        if (!pack_to_stdout && p->index_version > 1 &&
            check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) {
-               error("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
+               error("bad packed object CRC for %s",
+                     oid_to_hex(&entry->idx.oid));
                unuse_pack(&w_curs);
                return write_no_reuse_object(f, entry, limit, usable_delta);
        }
@@ -375,7 +384,8 @@ static off_t write_reuse_object(struct sha1file *f, struct object_entry *entry,
 
        if (!pack_to_stdout && p->index_version == 1 &&
            check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) {
-               error("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
+               error("corrupt packed object for %s",
+                     oid_to_hex(&entry->idx.oid));
                unuse_pack(&w_curs);
                return write_no_reuse_object(f, entry, limit, usable_delta);
        }
@@ -400,7 +410,7 @@ static off_t write_reuse_object(struct sha1file *f, struct object_entry *entry,
                        return 0;
                }
                sha1write(f, header, hdrlen);
-               sha1write(f, entry->delta->idx.sha1, 20);
+               sha1write(f, entry->delta->idx.oid.hash, 20);
                hdrlen += 20;
                reused_delta++;
        } else {
@@ -505,7 +515,7 @@ static enum write_one_status write_one(struct sha1file *f,
        recursing = (e->idx.offset == 1);
        if (recursing) {
                warning("recursive delta detected for object %s",
-                       sha1_to_hex(e->idx.sha1));
+                       oid_to_hex(&e->idx.oid));
                return WRITE_ONE_RECURSIVE;
        } else if (e->idx.offset || e->preferred_base) {
                /* offset is non zero if object is written already. */
@@ -718,7 +728,7 @@ static off_t write_reused_pack(struct sha1file *f)
        if (!is_pack_valid(reuse_packfile))
                die("packfile is invalid: %s", reuse_packfile->pack_name);
 
-       fd = git_open_noatime(reuse_packfile->pack_name);
+       fd = git_open(reuse_packfile->pack_name);
        if (fd < 0)
                die_errno("unable to open packfile for reuse: %s",
                          reuse_packfile->pack_name);
@@ -894,24 +904,15 @@ static void write_pack_file(void)
                        written, nr_result);
 }
 
-static void setup_delta_attr_check(struct git_attr_check *check)
-{
-       static struct git_attr *attr_delta;
-
-       if (!attr_delta)
-               attr_delta = git_attr("delta");
-
-       check[0].attr = attr_delta;
-}
-
 static int no_try_delta(const char *path)
 {
-       struct git_attr_check check[1];
+       static struct attr_check *check;
 
-       setup_delta_attr_check(check);
-       if (git_check_attr(path, ARRAY_SIZE(check), check))
+       if (!check)
+               check = attr_check_initl("delta", NULL);
+       if (git_check_attr(path, check))
                return 0;
-       if (ATTR_FALSE(check->value))
+       if (ATTR_FALSE(check->items[0].value))
                return 1;
        return 0;
 }
@@ -945,29 +946,80 @@ static int have_duplicate_entry(const unsigned char *sha1,
        return 1;
 }
 
+static int want_found_object(int exclude, struct packed_git *p)
+{
+       if (exclude)
+               return 1;
+       if (incremental)
+               return 0;
+
+       /*
+        * When asked to do --local (do not include an object that appears in a
+        * pack we borrow from elsewhere) or --honor-pack-keep (do not include
+        * an object that appears in a pack marked with .keep), finding a pack
+        * that matches the criteria is sufficient for us to decide to omit it.
+        * However, even if this pack does not satisfy the criteria, we need to
+        * make sure no copy of this object appears in _any_ pack that makes us
+        * to omit the object, so we need to check all the packs.
+        *
+        * We can however first check whether these options can possible matter;
+        * if they do not matter we know we want the object in generated pack.
+        * Otherwise, we signal "-1" at the end to tell the caller that we do
+        * not know either way, and it needs to check more packs.
+        */
+       if (!ignore_packed_keep &&
+           (!local || !have_non_local_packs))
+               return 1;
+
+       if (local && !p->pack_local)
+               return 0;
+       if (ignore_packed_keep && p->pack_local && p->pack_keep)
+               return 0;
+
+       /* we don't know yet; keep looking for more packs */
+       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.
+ * If the caller already knows an existing pack it wants to take the object
+ * from, that is passed in *found_pack and *found_offset; otherwise this
+ * function finds if there is any pack that has the object and returns the pack
+ * and its offset in these variables.
  */
 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;
+       struct mru_entry *entry;
+       int want;
 
        if (!exclude && local && has_loose_object_nonlocal(sha1))
                return 0;
 
-       *found_pack = NULL;
-       *found_offset = 0;
+       /*
+        * If we already know the pack object lives in, start checks from that
+        * pack - in the usual case when neither --local was given nor .keep files
+        * are present we will determine the answer right now.
+        */
+       if (*found_pack) {
+               want = want_found_object(exclude, *found_pack);
+               if (want != -1)
+                       return want;
+       }
+
+       for (entry = packed_git_mru->head; entry; entry = entry->next) {
+               struct packed_git *p = entry->item;
+               off_t offset;
+
+               if (p == *found_pack)
+                       offset = *found_offset;
+               else
+                       offset = find_pack_entry_one(sha1, p);
 
-       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))
@@ -975,31 +1027,11 @@ static int want_object_in_pack(const unsigned char *sha1,
                                *found_offset = offset;
                                *found_pack = p;
                        }
-                       if (exclude)
-                               return 1;
-                       if (incremental)
-                               return 0;
-
-                       /*
-                        * When asked to do --local (do not include an
-                        * object that appears in a pack we borrow
-                        * from elsewhere) or --honor-pack-keep (do not
-                        * include an object that appears in a pack marked
-                        * with .keep), we need to make sure no copy of this
-                        * object come from in _any_ pack that causes us to
-                        * omit it, and need to complete this loop.  When
-                        * neither option is in effect, we know the object
-                        * we just found is going to be packed, so break
-                        * out of the loop to return 1 now.
-                        */
-                       if (!ignore_packed_keep &&
-                           (!local || !have_non_local_packs))
-                               break;
-
-                       if (local && !p->pack_local)
-                               return 0;
-                       if (ignore_packed_keep && p->pack_local && p->pack_keep)
-                               return 0;
+                       want = want_found_object(exclude, p);
+                       if (!exclude && want > 0)
+                               mru_mark(packed_git_mru, entry);
+                       if (want != -1)
+                               return want;
                }
        }
 
@@ -1040,8 +1072,8 @@ static const char no_closure_warning[] = N_(
 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;
+       struct packed_git *found_pack = NULL;
+       off_t found_offset = 0;
        uint32_t index_pos;
 
        if (have_duplicate_entry(sha1, exclude, &index_pos))
@@ -1074,6 +1106,9 @@ static int add_object_entry_from_bitmap(const unsigned char *sha1,
        if (have_duplicate_entry(sha1, 0, &index_pos))
                return 0;
 
+       if (!want_object_in_pack(sha1, 0, &pack, &offset))
+               return 0;
+
        create_object_entry(sha1, type, name_hash, 0, 0, index_pos, pack, offset);
 
        display_progress(progress_state, nr_result);
@@ -1254,7 +1289,7 @@ static int done_pbase_path_pos(unsigned hash)
 
 static int check_pbase_path(unsigned hash)
 {
-       int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
+       int pos = done_pbase_path_pos(hash);
        if (0 <= pos)
                return 1;
        pos = -pos - 1;
@@ -1263,9 +1298,8 @@ static int check_pbase_path(unsigned hash)
                   done_pbase_paths_alloc);
        done_pbase_paths_num++;
        if (pos < done_pbase_paths_num)
-               memmove(done_pbase_paths + pos + 1,
-                       done_pbase_paths + pos,
-                       (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
+               MOVE_ARRAY(done_pbase_paths + pos + 1, done_pbase_paths + pos,
+                          done_pbase_paths_num - pos - 1);
        done_pbase_paths[pos] = hash;
        return 0;
 }
@@ -1340,12 +1374,10 @@ static void cleanup_preferred_base(void)
                if (!pbase_tree_cache[i])
                        continue;
                free(pbase_tree_cache[i]->tree_data);
-               free(pbase_tree_cache[i]);
-               pbase_tree_cache[i] = NULL;
+               FREE_AND_NULL(pbase_tree_cache[i]);
        }
 
-       free(done_pbase_paths);
-       done_pbase_paths = NULL;
+       FREE_AND_NULL(done_pbase_paths);
        done_pbase_paths_num = done_pbase_paths_alloc = 0;
 }
 
@@ -1403,7 +1435,7 @@ static void check_object(struct object_entry *entry)
                                ofs += 1;
                                if (!ofs || MSB(ofs, 7)) {
                                        error("delta base offset overflow in pack for %s",
-                                             sha1_to_hex(entry->idx.sha1));
+                                             oid_to_hex(&entry->idx.oid));
                                        goto give_up;
                                }
                                c = buf[used_0++];
@@ -1412,7 +1444,7 @@ static void check_object(struct object_entry *entry)
                        ofs = entry->in_pack_offset - ofs;
                        if (ofs <= 0 || ofs >= entry->in_pack_offset) {
                                error("delta base offset out of bound for %s",
-                                     sha1_to_hex(entry->idx.sha1));
+                                     oid_to_hex(&entry->idx.oid));
                                goto give_up;
                        }
                        if (reuse_delta && !entry->preferred_base) {
@@ -1469,7 +1501,7 @@ static void check_object(struct object_entry *entry)
                unuse_pack(&w_curs);
        }
 
-       entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
+       entry->type = sha1_object_info(entry->idx.oid.hash, &entry->size);
        /*
         * The error condition is checked in prepare_pack().  This is
         * to permit a missing preferred base object to be ignored
@@ -1485,7 +1517,7 @@ static int pack_offset_sort(const void *_a, const void *_b)
 
        /* avoid filesystem trashing with loose objects */
        if (!a->in_pack && !b->in_pack)
-               return hashcmp(a->idx.sha1, b->idx.sha1);
+               return oidcmp(&a->idx.oid, &b->idx.oid);
 
        if (a->in_pack < b->in_pack)
                return -1;
@@ -1495,6 +1527,171 @@ static int pack_offset_sort(const void *_a, const void *_b)
                        (a->in_pack_offset > b->in_pack_offset);
 }
 
+/*
+ * Drop an on-disk delta we were planning to reuse. Naively, this would
+ * just involve blanking out the "delta" field, but we have to deal
+ * with some extra book-keeping:
+ *
+ *   1. Removing ourselves from the delta_sibling linked list.
+ *
+ *   2. Updating our size/type to the non-delta representation. These were
+ *      either not recorded initially (size) or overwritten with the delta type
+ *      (type) when check_object() decided to reuse the delta.
+ *
+ *   3. Resetting our delta depth, as we are now a base object.
+ */
+static void drop_reused_delta(struct object_entry *entry)
+{
+       struct object_entry **p = &entry->delta->delta_child;
+       struct object_info oi = OBJECT_INFO_INIT;
+
+       while (*p) {
+               if (*p == entry)
+                       *p = (*p)->delta_sibling;
+               else
+                       p = &(*p)->delta_sibling;
+       }
+       entry->delta = NULL;
+       entry->depth = 0;
+
+       oi.sizep = &entry->size;
+       oi.typep = &entry->type;
+       if (packed_object_info(entry->in_pack, entry->in_pack_offset, &oi) < 0) {
+               /*
+                * We failed to get the info from this pack for some reason;
+                * fall back to sha1_object_info, which may find another copy.
+                * And if that fails, the error will be recorded in entry->type
+                * and dealt with in prepare_pack().
+                */
+               entry->type = sha1_object_info(entry->idx.oid.hash,
+                                              &entry->size);
+       }
+}
+
+/*
+ * Follow the chain of deltas from this entry onward, throwing away any links
+ * that cause us to hit a cycle (as determined by the DFS state flags in
+ * the entries).
+ *
+ * We also detect too-long reused chains that would violate our --depth
+ * limit.
+ */
+static void break_delta_chains(struct object_entry *entry)
+{
+       /*
+        * The actual depth of each object we will write is stored as an int,
+        * as it cannot exceed our int "depth" limit. But before we break
+        * changes based no that limit, we may potentially go as deep as the
+        * number of objects, which is elsewhere bounded to a uint32_t.
+        */
+       uint32_t total_depth;
+       struct object_entry *cur, *next;
+
+       for (cur = entry, total_depth = 0;
+            cur;
+            cur = cur->delta, total_depth++) {
+               if (cur->dfs_state == DFS_DONE) {
+                       /*
+                        * We've already seen this object and know it isn't
+                        * part of a cycle. We do need to append its depth
+                        * to our count.
+                        */
+                       total_depth += cur->depth;
+                       break;
+               }
+
+               /*
+                * We break cycles before looping, so an ACTIVE state (or any
+                * other cruft which made its way into the state variable)
+                * is a bug.
+                */
+               if (cur->dfs_state != DFS_NONE)
+                       die("BUG: confusing delta dfs state in first pass: %d",
+                           cur->dfs_state);
+
+               /*
+                * Now we know this is the first time we've seen the object. If
+                * it's not a delta, we're done traversing, but we'll mark it
+                * done to save time on future traversals.
+                */
+               if (!cur->delta) {
+                       cur->dfs_state = DFS_DONE;
+                       break;
+               }
+
+               /*
+                * Mark ourselves as active and see if the next step causes
+                * us to cycle to another active object. It's important to do
+                * this _before_ we loop, because it impacts where we make the
+                * cut, and thus how our total_depth counter works.
+                * E.g., We may see a partial loop like:
+                *
+                *   A -> B -> C -> D -> B
+                *
+                * Cutting B->C breaks the cycle. But now the depth of A is
+                * only 1, and our total_depth counter is at 3. The size of the
+                * error is always one less than the size of the cycle we
+                * broke. Commits C and D were "lost" from A's chain.
+                *
+                * If we instead cut D->B, then the depth of A is correct at 3.
+                * We keep all commits in the chain that we examined.
+                */
+               cur->dfs_state = DFS_ACTIVE;
+               if (cur->delta->dfs_state == DFS_ACTIVE) {
+                       drop_reused_delta(cur);
+                       cur->dfs_state = DFS_DONE;
+                       break;
+               }
+       }
+
+       /*
+        * And now that we've gone all the way to the bottom of the chain, we
+        * need to clear the active flags and set the depth fields as
+        * appropriate. Unlike the loop above, which can quit when it drops a
+        * delta, we need to keep going to look for more depth cuts. So we need
+        * an extra "next" pointer to keep going after we reset cur->delta.
+        */
+       for (cur = entry; cur; cur = next) {
+               next = cur->delta;
+
+               /*
+                * We should have a chain of zero or more ACTIVE states down to
+                * a final DONE. We can quit after the DONE, because either it
+                * has no bases, or we've already handled them in a previous
+                * call.
+                */
+               if (cur->dfs_state == DFS_DONE)
+                       break;
+               else if (cur->dfs_state != DFS_ACTIVE)
+                       die("BUG: confusing delta dfs state in second pass: %d",
+                           cur->dfs_state);
+
+               /*
+                * If the total_depth is more than depth, then we need to snip
+                * the chain into two or more smaller chains that don't exceed
+                * the maximum depth. Most of the resulting chains will contain
+                * (depth + 1) entries (i.e., depth deltas plus one base), and
+                * the last chain (i.e., the one containing entry) will contain
+                * whatever entries are left over, namely
+                * (total_depth % (depth + 1)) of them.
+                *
+                * Since we are iterating towards decreasing depth, we need to
+                * decrement total_depth as we go, and we need to write to the
+                * entry what its final depth will be after all of the
+                * snipping. Since we're snipping into chains of length (depth
+                * + 1) entries, the final depth of an entry will be its
+                * original depth modulo (depth + 1). Any time we encounter an
+                * entry whose final depth is supposed to be zero, we snip it
+                * from its delta base, thereby making it so.
+                */
+               cur->depth = (total_depth--) % (depth + 1);
+               if (!cur->depth)
+                       drop_reused_delta(cur);
+
+               cur->dfs_state = DFS_DONE;
+       }
+}
+
 static void get_object_details(void)
 {
        uint32_t i;
@@ -1503,7 +1700,7 @@ static void get_object_details(void)
        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);
+       QSORT(sorted_by_offset, to_pack.nr_objects, pack_offset_sort);
 
        for (i = 0; i < to_pack.nr_objects; i++) {
                struct object_entry *entry = sorted_by_offset[i];
@@ -1512,6 +1709,13 @@ static void get_object_details(void)
                        entry->no_try_delta = 1;
        }
 
+       /*
+        * This must happen in a second pass, since we rely on the delta
+        * information for the whole list being completed.
+        */
+       for (i = 0; i < to_pack.nr_objects; i++)
+               break_delta_chains(&to_pack.objects[i]);
+
        free(sorted_by_offset);
 }
 
@@ -1652,26 +1856,29 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
        /* Load data if not already done */
        if (!trg->data) {
                read_lock();
-               trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
+               trg->data = read_sha1_file(trg_entry->idx.oid.hash, &type,
+                                          &sz);
                read_unlock();
                if (!trg->data)
                        die("object %s cannot be read",
-                           sha1_to_hex(trg_entry->idx.sha1));
+                           oid_to_hex(&trg_entry->idx.oid));
                if (sz != trg_size)
                        die("object %s inconsistent object length (%lu vs %lu)",
-                           sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
+                           oid_to_hex(&trg_entry->idx.oid), sz,
+                           trg_size);
                *mem_usage += sz;
        }
        if (!src->data) {
                read_lock();
-               src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
+               src->data = read_sha1_file(src_entry->idx.oid.hash, &type,
+                                          &sz);
                read_unlock();
                if (!src->data) {
                        if (src_entry->preferred_base) {
                                static int warned = 0;
                                if (!warned++)
                                        warning("object %s cannot be read",
-                                               sha1_to_hex(src_entry->idx.sha1));
+                                               oid_to_hex(&src_entry->idx.oid));
                                /*
                                 * Those objects are not included in the
                                 * resulting pack.  Be resilient and ignore
@@ -1681,11 +1888,12 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
                                return 0;
                        }
                        die("object %s cannot be read",
-                           sha1_to_hex(src_entry->idx.sha1));
+                           oid_to_hex(&src_entry->idx.oid));
                }
                if (sz != src_size)
                        die("object %s inconsistent object length (%lu vs %lu)",
-                           sha1_to_hex(src_entry->idx.sha1), sz, src_size);
+                           oid_to_hex(&src_entry->idx.oid), sz,
+                           src_size);
                *mem_usage += sz;
        }
        if (!src->index) {
@@ -1759,8 +1967,7 @@ static unsigned long free_unpacked(struct unpacked *n)
        n->index = NULL;
        if (n->data) {
                freed_mem += n->entry->size;
-               free(n->data);
-               n->data = NULL;
+               FREE_AND_NULL(n->data);
        }
        n->entry = NULL;
        n->depth = 0;
@@ -1963,7 +2170,10 @@ static void *threaded_find_deltas(void *arg)
 {
        struct thread_params *me = arg;
 
+       progress_lock();
        while (me->remaining) {
+               progress_unlock();
+
                find_deltas(me->list, &me->remaining,
                            me->window, me->depth, me->processed);
 
@@ -1985,7 +2195,10 @@ static void *threaded_find_deltas(void *arg)
                        pthread_cond_wait(&me->cond, &me->mutex);
                me->data_ready = 0;
                pthread_mutex_unlock(&me->mutex);
+
+               progress_lock();
        }
+       progress_unlock();
        /* leave ->working 1 so that this doesn't get more work assigned */
        return NULL;
 }
@@ -2137,7 +2350,7 @@ static void add_tag_chain(const struct object_id *oid)
        if (packlist_find(&to_pack, oid->hash, NULL))
                return;
 
-       tag = lookup_tag(oid->hash);
+       tag = lookup_tag(oid);
        while (1) {
                if (!tag || parse_tag(tag) || !tag->tagged)
                        die("unable to pack objects reachable from tag %s",
@@ -2206,7 +2419,7 @@ static void prepare_pack(int window, int depth)
                        nr_deltas++;
                        if (entry->type < 0)
                                die("unable to get type of object %s",
-                                   sha1_to_hex(entry->idx.sha1));
+                                   oid_to_hex(&entry->idx.oid));
                } else {
                        if (entry->type < 0) {
                                /*
@@ -2225,7 +2438,7 @@ static void prepare_pack(int window, int depth)
                if (progress)
                        progress_state = start_progress(_("Compressing objects"),
                                                        nr_deltas);
-               qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
+               QSORT(delta_list, n, type_size_sort);
                ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
                stop_progress(&progress_state);
                if (nr_done != nr_deltas)
@@ -2248,16 +2461,6 @@ static int git_pack_config(const char *k, const char *v, void *cb)
                depth = git_config_int(k, v);
                return 0;
        }
-       if (!strcmp(k, "pack.compression")) {
-               int level = git_config_int(k, v);
-               if (level == -1)
-                       level = Z_DEFAULT_COMPRESSION;
-               else if (level < 0 || level > Z_BEST_COMPRESSION)
-                       die("bad pack compression level %d", level);
-               pack_compression_level = level;
-               pack_compression_seen = 1;
-               return 0;
-       }
        if (!strcmp(k, "pack.deltacachesize")) {
                max_delta_cache_size = git_config_int(k, v);
                return 0;
@@ -2273,7 +2476,7 @@ static int git_pack_config(const char *k, const char *v, void *cb)
                        write_bitmap_options &= ~BITMAP_OPT_HASH_CACHE;
        }
        if (!strcmp(k, "pack.usebitmaps")) {
-               use_bitmap_index = git_config_bool(k, v);
+               use_bitmap_index_default = git_config_bool(k, v);
                return 0;
        }
        if (!strcmp(k, "pack.threads")) {
@@ -2282,8 +2485,10 @@ static int git_pack_config(const char *k, const char *v, void *cb)
                        die("invalid number of threads specified (%d)",
                            delta_search_threads);
 #ifdef NO_PTHREADS
-               if (delta_search_threads != 1)
+               if (delta_search_threads != 1) {
                        warning("no threads support, ignoring %s", k);
+                       delta_search_threads = 0;
+               }
 #endif
                return 0;
        }
@@ -2357,8 +2562,8 @@ struct in_pack_object {
 };
 
 struct in_pack {
-       int alloc;
-       int nr;
+       unsigned int alloc;
+       unsigned int nr;
        struct in_pack_object *array;
 };
 
@@ -2417,8 +2622,7 @@ static void add_objects_in_unpacked_packs(struct rev_info *revs)
        }
 
        if (in_pack.nr) {
-               qsort(in_pack.array, in_pack.nr, sizeof(in_pack.array[0]),
-                     ofscmp);
+               QSORT(in_pack.array, in_pack.nr, ofscmp);
                for (i = 0; i < in_pack.nr; i++) {
                        struct object *o = in_pack.array[i].object;
                        add_object_entry(o->oid.hash, o->type, "", 0);
@@ -2427,17 +2631,17 @@ static void add_objects_in_unpacked_packs(struct rev_info *revs)
        free(in_pack.array);
 }
 
-static int add_loose_object(const unsigned char *sha1, const char *path,
+static int add_loose_object(const struct object_id *oid, const char *path,
                            void *data)
 {
-       enum object_type type = sha1_object_info(sha1, NULL);
+       enum object_type type = sha1_object_info(oid->hash, NULL);
 
        if (type < 0) {
                warning("loose object at %s could not be examined", path);
                return 0;
        }
 
-       add_object_entry(sha1, type, "", 0);
+       add_object_entry(oid->hash, type, "", 0);
        return 0;
 }
 
@@ -2483,16 +2687,16 @@ static int has_sha1_pack_kept_or_nonlocal(const unsigned char *sha1)
  *
  * This is filled by get_object_list.
  */
-static struct sha1_array recent_objects;
+static struct oid_array recent_objects;
 
-static int loosened_object_can_be_discarded(const unsigned char *sha1,
-                                           unsigned long mtime)
+static int loosened_object_can_be_discarded(const struct object_id *oid,
+                                           timestamp_t mtime)
 {
        if (!unpack_unreachable_expiration)
                return 0;
        if (mtime > unpack_unreachable_expiration)
                return 0;
-       if (sha1_array_lookup(&recent_objects, sha1) >= 0)
+       if (oid_array_lookup(&recent_objects, oid) >= 0)
                return 0;
        return 1;
 }
@@ -2501,7 +2705,7 @@ static void loosen_unused_packed_objects(struct rev_info *revs)
 {
        struct packed_git *p;
        uint32_t i;
-       const unsigned char *sha1;
+       struct object_id oid;
 
        for (p = packed_git; p; p = p->next) {
                if (!p->pack_local || p->pack_keep)
@@ -2511,24 +2715,28 @@ static void loosen_unused_packed_objects(struct rev_info *revs)
                        die("cannot open pack index");
 
                for (i = 0; i < p->num_objects; i++) {
-                       sha1 = nth_packed_object_sha1(p, i);
-                       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))
+                       nth_packed_object_oid(&oid, p, i);
+                       if (!packlist_find(&to_pack, oid.hash, NULL) &&
+                           !has_sha1_pack_kept_or_nonlocal(oid.hash) &&
+                           !loosened_object_can_be_discarded(&oid, p->mtime))
+                               if (force_object_loose(oid.hash, 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.
+ * This tracks any options which pack-reuse code expects to be on, or 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;
+       return pack_to_stdout &&
+              allow_ofs_delta &&
+              !ignore_packed_keep &&
+              (!local || !have_non_local_packs) &&
+              !incremental;
 }
 
 static int get_object_list_from_bitmap(struct rev_info *revs)
@@ -2554,12 +2762,12 @@ static void record_recent_object(struct object *obj,
                                 const char *name,
                                 void *data)
 {
-       sha1_array_append(&recent_objects, obj->oid.hash);
+       oid_array_append(&recent_objects, &obj->oid);
 }
 
 static void record_recent_commit(struct commit *commit, void *data)
 {
-       sha1_array_append(&recent_objects, commit->object.oid.hash);
+       oid_array_append(&recent_objects, &commit->object.oid);
 }
 
 static void get_object_list(int ac, const char **av)
@@ -2588,10 +2796,10 @@ static void get_object_list(int ac, const char **av)
                                continue;
                        }
                        if (starts_with(line, "--shallow ")) {
-                               unsigned char sha1[20];
-                               if (get_sha1_hex(line + 10, sha1))
+                               struct object_id oid;
+                               if (get_oid_hex(line + 10, &oid))
                                        die("not an SHA-1 '%s'", line + 10);
-                               register_shallow(sha1);
+                               register_shallow(&oid);
                                use_bitmap_index = 0;
                                continue;
                        }
@@ -2627,7 +2835,7 @@ static void get_object_list(int ac, const char **av)
        if (unpack_unreachable)
                loosen_unused_packed_objects(&revs);
 
-       sha1_array_clear(&recent_objects);
+       oid_array_clear(&recent_objects);
 }
 
 static int option_parse_index_version(const struct option *opt,
@@ -2750,8 +2958,6 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 
        reset_pack_idx_option(&pack_idx_opts);
        git_config(git_pack_config, NULL);
-       if (!pack_compression_seen && core_compression_seen)
-               pack_compression_level = core_compression_level;
 
        progress = isatty(2);
        argc = parse_options(argc, argv, prefix, pack_objects_options,
@@ -2821,7 +3027,23 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
        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())
+       /*
+        * "soft" reasons not to use bitmaps - for on-disk repack by default we want
+        *
+        * - to produce good pack (with bitmap index not-yet-packed objects are
+        *   packed in suboptimal order).
+        *
+        * - to use more robust pack-generation codepath (avoiding possible
+        *   bugs in bitmap code and possible bitmap index corruption).
+        */
+       if (!pack_to_stdout)
+               use_bitmap_index_default = 0;
+
+       if (use_bitmap_index < 0)
+               use_bitmap_index = use_bitmap_index_default;
+
+       /* "hard" reasons not to use bitmaps; these just won't work at all */
+       if (!use_internal_rev_list || (!pack_to_stdout && write_bitmap_index) || is_repository_shallow())
                use_bitmap_index = 0;
 
        if (pack_to_stdout || !rev_list_all)