mirror of
https://github.com/git/git
synced 2024-08-24 18:26:02 +00:00
![Elijah Newren](/assets/img/avatar_default.png)
Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
842 lines
20 KiB
C
842 lines
20 KiB
C
#include "git-compat-util.h"
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#include "alloc.h"
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#include "environment.h"
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#include "gettext.h"
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#include "hex.h"
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#include "object-store.h"
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#include "commit.h"
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#include "tag.h"
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#include "diff.h"
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#include "revision.h"
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#include "list-objects.h"
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#include "progress.h"
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#include "pack-revindex.h"
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#include "pack.h"
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#include "pack-bitmap.h"
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#include "hash-lookup.h"
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#include "pack-objects.h"
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#include "commit-reach.h"
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#include "prio-queue.h"
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#include "trace2.h"
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#include "tree.h"
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#include "tree-walk.h"
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struct bitmapped_commit {
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struct commit *commit;
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struct ewah_bitmap *bitmap;
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struct ewah_bitmap *write_as;
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int flags;
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int xor_offset;
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uint32_t commit_pos;
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};
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struct bitmap_writer {
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struct ewah_bitmap *commits;
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struct ewah_bitmap *trees;
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struct ewah_bitmap *blobs;
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struct ewah_bitmap *tags;
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kh_oid_map_t *bitmaps;
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struct packing_data *to_pack;
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struct bitmapped_commit *selected;
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unsigned int selected_nr, selected_alloc;
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struct progress *progress;
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int show_progress;
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unsigned char pack_checksum[GIT_MAX_RAWSZ];
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};
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static struct bitmap_writer writer;
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void bitmap_writer_show_progress(int show)
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{
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writer.show_progress = show;
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}
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/**
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* Build the initial type index for the packfile or multi-pack-index
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*/
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void bitmap_writer_build_type_index(struct packing_data *to_pack,
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struct pack_idx_entry **index,
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uint32_t index_nr)
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{
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uint32_t i;
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writer.commits = ewah_new();
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writer.trees = ewah_new();
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writer.blobs = ewah_new();
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writer.tags = ewah_new();
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ALLOC_ARRAY(to_pack->in_pack_pos, to_pack->nr_objects);
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for (i = 0; i < index_nr; ++i) {
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struct object_entry *entry = (struct object_entry *)index[i];
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enum object_type real_type;
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oe_set_in_pack_pos(to_pack, entry, i);
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switch (oe_type(entry)) {
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case OBJ_COMMIT:
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case OBJ_TREE:
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case OBJ_BLOB:
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case OBJ_TAG:
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real_type = oe_type(entry);
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break;
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default:
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real_type = oid_object_info(to_pack->repo,
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&entry->idx.oid, NULL);
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break;
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}
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switch (real_type) {
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case OBJ_COMMIT:
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ewah_set(writer.commits, i);
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break;
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case OBJ_TREE:
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ewah_set(writer.trees, i);
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break;
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case OBJ_BLOB:
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ewah_set(writer.blobs, i);
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break;
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case OBJ_TAG:
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ewah_set(writer.tags, i);
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break;
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default:
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die("Missing type information for %s (%d/%d)",
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oid_to_hex(&entry->idx.oid), real_type,
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oe_type(entry));
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}
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}
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}
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/**
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* Compute the actual bitmaps
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*/
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static inline void push_bitmapped_commit(struct commit *commit)
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{
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if (writer.selected_nr >= writer.selected_alloc) {
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writer.selected_alloc = (writer.selected_alloc + 32) * 2;
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REALLOC_ARRAY(writer.selected, writer.selected_alloc);
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}
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writer.selected[writer.selected_nr].commit = commit;
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writer.selected[writer.selected_nr].bitmap = NULL;
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writer.selected[writer.selected_nr].flags = 0;
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writer.selected_nr++;
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}
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static uint32_t find_object_pos(const struct object_id *oid, int *found)
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{
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struct object_entry *entry = packlist_find(writer.to_pack, oid);
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if (!entry) {
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if (found)
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*found = 0;
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warning("Failed to write bitmap index. Packfile doesn't have full closure "
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"(object %s is missing)", oid_to_hex(oid));
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return 0;
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}
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if (found)
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*found = 1;
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return oe_in_pack_pos(writer.to_pack, entry);
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}
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static void compute_xor_offsets(void)
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{
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static const int MAX_XOR_OFFSET_SEARCH = 10;
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int i, next = 0;
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while (next < writer.selected_nr) {
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struct bitmapped_commit *stored = &writer.selected[next];
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int best_offset = 0;
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struct ewah_bitmap *best_bitmap = stored->bitmap;
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struct ewah_bitmap *test_xor;
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for (i = 1; i <= MAX_XOR_OFFSET_SEARCH; ++i) {
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int curr = next - i;
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if (curr < 0)
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break;
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test_xor = ewah_pool_new();
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ewah_xor(writer.selected[curr].bitmap, stored->bitmap, test_xor);
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if (test_xor->buffer_size < best_bitmap->buffer_size) {
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if (best_bitmap != stored->bitmap)
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ewah_pool_free(best_bitmap);
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best_bitmap = test_xor;
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best_offset = i;
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} else {
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ewah_pool_free(test_xor);
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}
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}
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stored->xor_offset = best_offset;
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stored->write_as = best_bitmap;
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next++;
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}
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}
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struct bb_commit {
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struct commit_list *reverse_edges;
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struct bitmap *commit_mask;
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struct bitmap *bitmap;
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unsigned selected:1,
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maximal:1;
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unsigned idx; /* within selected array */
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};
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define_commit_slab(bb_data, struct bb_commit);
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struct bitmap_builder {
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struct bb_data data;
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struct commit **commits;
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size_t commits_nr, commits_alloc;
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};
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static void bitmap_builder_init(struct bitmap_builder *bb,
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struct bitmap_writer *writer,
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struct bitmap_index *old_bitmap)
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{
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struct rev_info revs;
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struct commit *commit;
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struct commit_list *reusable = NULL;
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struct commit_list *r;
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unsigned int i, num_maximal = 0;
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memset(bb, 0, sizeof(*bb));
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init_bb_data(&bb->data);
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reset_revision_walk();
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repo_init_revisions(writer->to_pack->repo, &revs, NULL);
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revs.topo_order = 1;
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revs.first_parent_only = 1;
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for (i = 0; i < writer->selected_nr; i++) {
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struct commit *c = writer->selected[i].commit;
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struct bb_commit *ent = bb_data_at(&bb->data, c);
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ent->selected = 1;
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ent->maximal = 1;
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ent->idx = i;
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ent->commit_mask = bitmap_new();
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bitmap_set(ent->commit_mask, i);
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add_pending_object(&revs, &c->object, "");
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}
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if (prepare_revision_walk(&revs))
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die("revision walk setup failed");
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while ((commit = get_revision(&revs))) {
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struct commit_list *p = commit->parents;
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struct bb_commit *c_ent;
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parse_commit_or_die(commit);
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c_ent = bb_data_at(&bb->data, commit);
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/*
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* If there is no commit_mask, there is no reason to iterate
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* over this commit; it is not selected (if it were, it would
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* not have a blank commit mask) and all its children have
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* existing bitmaps (see the comment starting with "This commit
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* has an existing bitmap" below), so it does not contribute
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* anything to the final bitmap file or its descendants.
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*/
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if (!c_ent->commit_mask)
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continue;
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if (old_bitmap && bitmap_for_commit(old_bitmap, commit)) {
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/*
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* This commit has an existing bitmap, so we can
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* get its bits immediately without an object
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* walk. That is, it is reusable as-is and there is no
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* need to continue walking beyond it.
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*
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* Mark it as such and add it to bb->commits separately
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* to avoid allocating a position in the commit mask.
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*/
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commit_list_insert(commit, &reusable);
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goto next;
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}
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if (c_ent->maximal) {
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num_maximal++;
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ALLOC_GROW(bb->commits, bb->commits_nr + 1, bb->commits_alloc);
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bb->commits[bb->commits_nr++] = commit;
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}
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if (p) {
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struct bb_commit *p_ent = bb_data_at(&bb->data, p->item);
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int c_not_p, p_not_c;
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if (!p_ent->commit_mask) {
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p_ent->commit_mask = bitmap_new();
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c_not_p = 1;
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p_not_c = 0;
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} else {
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c_not_p = bitmap_is_subset(c_ent->commit_mask, p_ent->commit_mask);
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p_not_c = bitmap_is_subset(p_ent->commit_mask, c_ent->commit_mask);
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}
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if (!c_not_p)
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continue;
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bitmap_or(p_ent->commit_mask, c_ent->commit_mask);
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if (p_not_c)
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p_ent->maximal = 1;
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else {
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p_ent->maximal = 0;
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free_commit_list(p_ent->reverse_edges);
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p_ent->reverse_edges = NULL;
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}
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if (c_ent->maximal) {
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commit_list_insert(commit, &p_ent->reverse_edges);
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} else {
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struct commit_list *cc = c_ent->reverse_edges;
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for (; cc; cc = cc->next) {
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if (!commit_list_contains(cc->item, p_ent->reverse_edges))
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commit_list_insert(cc->item, &p_ent->reverse_edges);
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}
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}
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}
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next:
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bitmap_free(c_ent->commit_mask);
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c_ent->commit_mask = NULL;
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}
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for (r = reusable; r; r = r->next) {
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ALLOC_GROW(bb->commits, bb->commits_nr + 1, bb->commits_alloc);
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bb->commits[bb->commits_nr++] = r->item;
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}
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trace2_data_intmax("pack-bitmap-write", the_repository,
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"num_selected_commits", writer->selected_nr);
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trace2_data_intmax("pack-bitmap-write", the_repository,
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"num_maximal_commits", num_maximal);
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release_revisions(&revs);
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free_commit_list(reusable);
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}
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static void bitmap_builder_clear(struct bitmap_builder *bb)
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{
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clear_bb_data(&bb->data);
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free(bb->commits);
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bb->commits_nr = bb->commits_alloc = 0;
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}
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static int fill_bitmap_tree(struct bitmap *bitmap,
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struct tree *tree)
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{
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int found;
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uint32_t pos;
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struct tree_desc desc;
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struct name_entry entry;
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/*
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* If our bit is already set, then there is nothing to do. Both this
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* tree and all of its children will be set.
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*/
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pos = find_object_pos(&tree->object.oid, &found);
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if (!found)
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return -1;
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if (bitmap_get(bitmap, pos))
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return 0;
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bitmap_set(bitmap, pos);
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if (parse_tree(tree) < 0)
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die("unable to load tree object %s",
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oid_to_hex(&tree->object.oid));
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init_tree_desc(&desc, tree->buffer, tree->size);
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while (tree_entry(&desc, &entry)) {
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switch (object_type(entry.mode)) {
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case OBJ_TREE:
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if (fill_bitmap_tree(bitmap,
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lookup_tree(the_repository, &entry.oid)) < 0)
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return -1;
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break;
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case OBJ_BLOB:
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pos = find_object_pos(&entry.oid, &found);
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if (!found)
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return -1;
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bitmap_set(bitmap, pos);
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break;
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default:
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/* Gitlink, etc; not reachable */
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break;
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}
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}
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free_tree_buffer(tree);
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return 0;
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}
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static int reused_bitmaps_nr;
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static int fill_bitmap_commit(struct bb_commit *ent,
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struct commit *commit,
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struct prio_queue *queue,
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struct prio_queue *tree_queue,
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struct bitmap_index *old_bitmap,
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const uint32_t *mapping)
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{
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int found;
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uint32_t pos;
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if (!ent->bitmap)
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ent->bitmap = bitmap_new();
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prio_queue_put(queue, commit);
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while (queue->nr) {
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struct commit_list *p;
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struct commit *c = prio_queue_get(queue);
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if (old_bitmap && mapping) {
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struct ewah_bitmap *old = bitmap_for_commit(old_bitmap, c);
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/*
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* If this commit has an old bitmap, then translate that
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* bitmap and add its bits to this one. No need to walk
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* parents or the tree for this commit.
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*/
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if (old && !rebuild_bitmap(mapping, old, ent->bitmap)) {
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reused_bitmaps_nr++;
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continue;
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}
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}
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/*
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* Mark ourselves and queue our tree. The commit
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* walk ensures we cover all parents.
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*/
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pos = find_object_pos(&c->object.oid, &found);
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if (!found)
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return -1;
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bitmap_set(ent->bitmap, pos);
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prio_queue_put(tree_queue,
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repo_get_commit_tree(the_repository, c));
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for (p = c->parents; p; p = p->next) {
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pos = find_object_pos(&p->item->object.oid, &found);
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if (!found)
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return -1;
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if (!bitmap_get(ent->bitmap, pos)) {
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bitmap_set(ent->bitmap, pos);
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prio_queue_put(queue, p->item);
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}
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}
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}
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while (tree_queue->nr) {
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if (fill_bitmap_tree(ent->bitmap,
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prio_queue_get(tree_queue)) < 0)
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return -1;
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}
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return 0;
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}
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static void store_selected(struct bb_commit *ent, struct commit *commit)
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{
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struct bitmapped_commit *stored = &writer.selected[ent->idx];
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khiter_t hash_pos;
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int hash_ret;
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stored->bitmap = bitmap_to_ewah(ent->bitmap);
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hash_pos = kh_put_oid_map(writer.bitmaps, commit->object.oid, &hash_ret);
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if (hash_ret == 0)
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die("Duplicate entry when writing index: %s",
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oid_to_hex(&commit->object.oid));
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kh_value(writer.bitmaps, hash_pos) = stored;
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}
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int bitmap_writer_build(struct packing_data *to_pack)
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{
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struct bitmap_builder bb;
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size_t i;
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int nr_stored = 0; /* for progress */
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struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
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struct prio_queue tree_queue = { NULL };
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struct bitmap_index *old_bitmap;
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uint32_t *mapping;
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int closed = 1; /* until proven otherwise */
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writer.bitmaps = kh_init_oid_map();
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writer.to_pack = to_pack;
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if (writer.show_progress)
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writer.progress = start_progress("Building bitmaps", writer.selected_nr);
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trace2_region_enter("pack-bitmap-write", "building_bitmaps_total",
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the_repository);
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old_bitmap = prepare_bitmap_git(to_pack->repo);
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if (old_bitmap)
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mapping = create_bitmap_mapping(old_bitmap, to_pack);
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else
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mapping = NULL;
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bitmap_builder_init(&bb, &writer, old_bitmap);
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for (i = bb.commits_nr; i > 0; i--) {
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struct commit *commit = bb.commits[i-1];
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struct bb_commit *ent = bb_data_at(&bb.data, commit);
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struct commit *child;
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int reused = 0;
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if (fill_bitmap_commit(ent, commit, &queue, &tree_queue,
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old_bitmap, mapping) < 0) {
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closed = 0;
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break;
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}
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if (ent->selected) {
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store_selected(ent, commit);
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nr_stored++;
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display_progress(writer.progress, nr_stored);
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}
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while ((child = pop_commit(&ent->reverse_edges))) {
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struct bb_commit *child_ent =
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bb_data_at(&bb.data, child);
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if (child_ent->bitmap)
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bitmap_or(child_ent->bitmap, ent->bitmap);
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else if (reused)
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child_ent->bitmap = bitmap_dup(ent->bitmap);
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else {
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child_ent->bitmap = ent->bitmap;
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reused = 1;
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}
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}
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if (!reused)
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bitmap_free(ent->bitmap);
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ent->bitmap = NULL;
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}
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clear_prio_queue(&queue);
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clear_prio_queue(&tree_queue);
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bitmap_builder_clear(&bb);
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free_bitmap_index(old_bitmap);
|
|
free(mapping);
|
|
|
|
trace2_region_leave("pack-bitmap-write", "building_bitmaps_total",
|
|
the_repository);
|
|
trace2_data_intmax("pack-bitmap-write", the_repository,
|
|
"building_bitmaps_reused", reused_bitmaps_nr);
|
|
|
|
stop_progress(&writer.progress);
|
|
|
|
if (closed)
|
|
compute_xor_offsets();
|
|
return closed ? 0 : -1;
|
|
}
|
|
|
|
/**
|
|
* Select the commits that will be bitmapped
|
|
*/
|
|
static inline unsigned int next_commit_index(unsigned int idx)
|
|
{
|
|
static const unsigned int MIN_COMMITS = 100;
|
|
static const unsigned int MAX_COMMITS = 5000;
|
|
|
|
static const unsigned int MUST_REGION = 100;
|
|
static const unsigned int MIN_REGION = 20000;
|
|
|
|
unsigned int offset, next;
|
|
|
|
if (idx <= MUST_REGION)
|
|
return 0;
|
|
|
|
if (idx <= MIN_REGION) {
|
|
offset = idx - MUST_REGION;
|
|
return (offset < MIN_COMMITS) ? offset : MIN_COMMITS;
|
|
}
|
|
|
|
offset = idx - MIN_REGION;
|
|
next = (offset < MAX_COMMITS) ? offset : MAX_COMMITS;
|
|
|
|
return (next > MIN_COMMITS) ? next : MIN_COMMITS;
|
|
}
|
|
|
|
static int date_compare(const void *_a, const void *_b)
|
|
{
|
|
struct commit *a = *(struct commit **)_a;
|
|
struct commit *b = *(struct commit **)_b;
|
|
return (long)b->date - (long)a->date;
|
|
}
|
|
|
|
void bitmap_writer_select_commits(struct commit **indexed_commits,
|
|
unsigned int indexed_commits_nr,
|
|
int max_bitmaps)
|
|
{
|
|
unsigned int i = 0, j, next;
|
|
|
|
QSORT(indexed_commits, indexed_commits_nr, date_compare);
|
|
|
|
if (indexed_commits_nr < 100) {
|
|
for (i = 0; i < indexed_commits_nr; ++i)
|
|
push_bitmapped_commit(indexed_commits[i]);
|
|
return;
|
|
}
|
|
|
|
if (writer.show_progress)
|
|
writer.progress = start_progress("Selecting bitmap commits", 0);
|
|
|
|
for (;;) {
|
|
struct commit *chosen = NULL;
|
|
|
|
next = next_commit_index(i);
|
|
|
|
if (i + next >= indexed_commits_nr)
|
|
break;
|
|
|
|
if (max_bitmaps > 0 && writer.selected_nr >= max_bitmaps) {
|
|
writer.selected_nr = max_bitmaps;
|
|
break;
|
|
}
|
|
|
|
if (next == 0) {
|
|
chosen = indexed_commits[i];
|
|
} else {
|
|
chosen = indexed_commits[i + next];
|
|
|
|
for (j = 0; j <= next; ++j) {
|
|
struct commit *cm = indexed_commits[i + j];
|
|
|
|
if ((cm->object.flags & NEEDS_BITMAP) != 0) {
|
|
chosen = cm;
|
|
break;
|
|
}
|
|
|
|
if (cm->parents && cm->parents->next)
|
|
chosen = cm;
|
|
}
|
|
}
|
|
|
|
push_bitmapped_commit(chosen);
|
|
|
|
i += next + 1;
|
|
display_progress(writer.progress, i);
|
|
}
|
|
|
|
stop_progress(&writer.progress);
|
|
}
|
|
|
|
|
|
static int hashwrite_ewah_helper(void *f, const void *buf, size_t len)
|
|
{
|
|
/* hashwrite will die on error */
|
|
hashwrite(f, buf, len);
|
|
return len;
|
|
}
|
|
|
|
/**
|
|
* Write the bitmap index to disk
|
|
*/
|
|
static inline void dump_bitmap(struct hashfile *f, struct ewah_bitmap *bitmap)
|
|
{
|
|
if (ewah_serialize_to(bitmap, hashwrite_ewah_helper, f) < 0)
|
|
die("Failed to write bitmap index");
|
|
}
|
|
|
|
static const struct object_id *oid_access(size_t pos, const void *table)
|
|
{
|
|
const struct pack_idx_entry * const *index = table;
|
|
return &index[pos]->oid;
|
|
}
|
|
|
|
static void write_selected_commits_v1(struct hashfile *f,
|
|
uint32_t *commit_positions,
|
|
off_t *offsets)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < writer.selected_nr; ++i) {
|
|
struct bitmapped_commit *stored = &writer.selected[i];
|
|
|
|
if (offsets)
|
|
offsets[i] = hashfile_total(f);
|
|
|
|
hashwrite_be32(f, commit_positions[i]);
|
|
hashwrite_u8(f, stored->xor_offset);
|
|
hashwrite_u8(f, stored->flags);
|
|
|
|
dump_bitmap(f, stored->write_as);
|
|
}
|
|
}
|
|
|
|
static int table_cmp(const void *_va, const void *_vb, void *_data)
|
|
{
|
|
uint32_t *commit_positions = _data;
|
|
uint32_t a = commit_positions[*(uint32_t *)_va];
|
|
uint32_t b = commit_positions[*(uint32_t *)_vb];
|
|
|
|
if (a > b)
|
|
return 1;
|
|
else if (a < b)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void write_lookup_table(struct hashfile *f,
|
|
uint32_t *commit_positions,
|
|
off_t *offsets)
|
|
{
|
|
uint32_t i;
|
|
uint32_t *table, *table_inv;
|
|
|
|
ALLOC_ARRAY(table, writer.selected_nr);
|
|
ALLOC_ARRAY(table_inv, writer.selected_nr);
|
|
|
|
for (i = 0; i < writer.selected_nr; i++)
|
|
table[i] = i;
|
|
|
|
/*
|
|
* At the end of this sort table[j] = i means that the i'th
|
|
* bitmap corresponds to j'th bitmapped commit (among the selected
|
|
* commits) in lex order of OIDs.
|
|
*/
|
|
QSORT_S(table, writer.selected_nr, table_cmp, commit_positions);
|
|
|
|
/* table_inv helps us discover that relationship (i'th bitmap
|
|
* to j'th commit by j = table_inv[i])
|
|
*/
|
|
for (i = 0; i < writer.selected_nr; i++)
|
|
table_inv[table[i]] = i;
|
|
|
|
trace2_region_enter("pack-bitmap-write", "writing_lookup_table", the_repository);
|
|
for (i = 0; i < writer.selected_nr; i++) {
|
|
struct bitmapped_commit *selected = &writer.selected[table[i]];
|
|
uint32_t xor_offset = selected->xor_offset;
|
|
uint32_t xor_row;
|
|
|
|
if (xor_offset) {
|
|
/*
|
|
* xor_index stores the index (in the bitmap entries)
|
|
* of the corresponding xor bitmap. But we need to convert
|
|
* this index into lookup table's index. So, table_inv[xor_index]
|
|
* gives us the index position w.r.t. the lookup table.
|
|
*
|
|
* If "k = table[i] - xor_offset" then the xor base is the k'th
|
|
* bitmap. `table_inv[k]` gives us the position of that bitmap
|
|
* in the lookup table.
|
|
*/
|
|
uint32_t xor_index = table[i] - xor_offset;
|
|
xor_row = table_inv[xor_index];
|
|
} else {
|
|
xor_row = 0xffffffff;
|
|
}
|
|
|
|
hashwrite_be32(f, commit_positions[table[i]]);
|
|
hashwrite_be64(f, (uint64_t)offsets[table[i]]);
|
|
hashwrite_be32(f, xor_row);
|
|
}
|
|
trace2_region_leave("pack-bitmap-write", "writing_lookup_table", the_repository);
|
|
|
|
free(table);
|
|
free(table_inv);
|
|
}
|
|
|
|
static void write_hash_cache(struct hashfile *f,
|
|
struct pack_idx_entry **index,
|
|
uint32_t index_nr)
|
|
{
|
|
uint32_t i;
|
|
|
|
for (i = 0; i < index_nr; ++i) {
|
|
struct object_entry *entry = (struct object_entry *)index[i];
|
|
hashwrite_be32(f, entry->hash);
|
|
}
|
|
}
|
|
|
|
void bitmap_writer_set_checksum(const unsigned char *sha1)
|
|
{
|
|
hashcpy(writer.pack_checksum, sha1);
|
|
}
|
|
|
|
void bitmap_writer_finish(struct pack_idx_entry **index,
|
|
uint32_t index_nr,
|
|
const char *filename,
|
|
uint16_t options)
|
|
{
|
|
static uint16_t default_version = 1;
|
|
static uint16_t flags = BITMAP_OPT_FULL_DAG;
|
|
struct strbuf tmp_file = STRBUF_INIT;
|
|
struct hashfile *f;
|
|
uint32_t *commit_positions = NULL;
|
|
off_t *offsets = NULL;
|
|
uint32_t i;
|
|
|
|
struct bitmap_disk_header header;
|
|
|
|
int fd = odb_mkstemp(&tmp_file, "pack/tmp_bitmap_XXXXXX");
|
|
|
|
f = hashfd(fd, tmp_file.buf);
|
|
|
|
memcpy(header.magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE));
|
|
header.version = htons(default_version);
|
|
header.options = htons(flags | options);
|
|
header.entry_count = htonl(writer.selected_nr);
|
|
hashcpy(header.checksum, writer.pack_checksum);
|
|
|
|
hashwrite(f, &header, sizeof(header) - GIT_MAX_RAWSZ + the_hash_algo->rawsz);
|
|
dump_bitmap(f, writer.commits);
|
|
dump_bitmap(f, writer.trees);
|
|
dump_bitmap(f, writer.blobs);
|
|
dump_bitmap(f, writer.tags);
|
|
|
|
if (options & BITMAP_OPT_LOOKUP_TABLE)
|
|
CALLOC_ARRAY(offsets, index_nr);
|
|
|
|
ALLOC_ARRAY(commit_positions, writer.selected_nr);
|
|
|
|
for (i = 0; i < writer.selected_nr; i++) {
|
|
struct bitmapped_commit *stored = &writer.selected[i];
|
|
int commit_pos = oid_pos(&stored->commit->object.oid, index, index_nr, oid_access);
|
|
|
|
if (commit_pos < 0)
|
|
BUG(_("trying to write commit not in index"));
|
|
|
|
commit_positions[i] = commit_pos;
|
|
}
|
|
|
|
write_selected_commits_v1(f, commit_positions, offsets);
|
|
|
|
if (options & BITMAP_OPT_LOOKUP_TABLE)
|
|
write_lookup_table(f, commit_positions, offsets);
|
|
|
|
if (options & BITMAP_OPT_HASH_CACHE)
|
|
write_hash_cache(f, index, index_nr);
|
|
|
|
finalize_hashfile(f, NULL, FSYNC_COMPONENT_PACK_METADATA,
|
|
CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE);
|
|
|
|
if (adjust_shared_perm(tmp_file.buf))
|
|
die_errno("unable to make temporary bitmap file readable");
|
|
|
|
if (rename(tmp_file.buf, filename))
|
|
die_errno("unable to rename temporary bitmap file to '%s'", filename);
|
|
|
|
strbuf_release(&tmp_file);
|
|
free(commit_positions);
|
|
free(offsets);
|
|
}
|