Merge branch 'tb/idx-midx-race-fix'

Processes that access packdata while the .idx file gets removed
(e.g. while repacking) did not fail or fall back gracefully as they
could.

* tb/idx-midx-race-fix:
  midx.c: protect against disappearing packs
  packfile.c: protect against disappearing indexes

diff --git a/midx.c b/midx.c
index da03c1449aa119b03a34605b72056b8727318eb6..79c282b070d26d5ffac866feaaee244fea986d43 100644 (file)
--- a/midx.c
+++ b/midx.c
@@ -298,7 +298,7 @@ static int nth_midxed_pack_entry(struct repository *r,
        pack_int_id = nth_midxed_pack_int_id(m, pos);
 
        if (prepare_midx_pack(r, m, pack_int_id))
-               die(_("error preparing packfile from multi-pack-index"));
+               return 0;
        p = m->packs[pack_int_id];
 
        /*

diff --git a/packfile.c b/packfile.c
index 9702b1218b86021ccd5d47b32dd59655899f63e0..86f5c8dbf6677195ffca0e03f3cf810e84c5f0df 100644 (file)
--- a/packfile.c
+++ b/packfile.c
@@ -514,19 +514,8 @@ static int open_packed_git_1(struct packed_git *p)
        ssize_t read_result;
        const unsigned hashsz = the_hash_algo->rawsz;
 
-       if (!p->index_data) {
-               struct multi_pack_index *m;
-               const char *pack_name = pack_basename(p);
-
-               for (m = the_repository->objects->multi_pack_index;
-                    m; m = m->next) {
-                       if (midx_contains_pack(m, pack_name))
-                               break;
-               }
-
-               if (!m && open_pack_index(p))
-                       return error("packfile %s index unavailable", p->pack_name);
-       }
+       if (open_pack_index(p))
+               return error("packfile %s index unavailable", p->pack_name);
 
        if (!pack_max_fds) {
                unsigned int max_fds = get_max_fd_limit();
@@ -567,10 +556,6 @@ static int open_packed_git_1(struct packed_git *p)
                        " supported (try upgrading GIT to a newer version)",
                        p->pack_name, ntohl(hdr.hdr_version));
 
-       /* Skip index checking if in multi-pack-index */
-       if (!p->index_data)
-               return 0;
-
        /* Verify the pack matches its index. */
        if (p->num_objects != ntohl(hdr.hdr_entries))
                return error("packfile %s claims to have %"PRIu32" objects"

diff --git a/t/t5319-multi-pack-index.sh b/t/t5319-multi-pack-index.sh
index ace469c95c2faaf91798639ab3d686d1637f7352..297de502a94fdfc255e9e3de4db801e2f15d02f2 100755 (executable)
--- a/t/t5319-multi-pack-index.sh
+++ b/t/t5319-multi-pack-index.sh
@@ -138,7 +138,7 @@ test_expect_success 'write midx with one v2 pack' '
 
 compare_results_with_midx "one v2 pack"
 
-test_expect_success 'corrupt idx not opened' '
+test_expect_success 'corrupt idx reports errors' '
        idx=$(test-tool read-midx $objdir | grep "\.idx\$") &&
        mv $objdir/pack/$idx backup-$idx &&
        test_when_finished "mv backup-\$idx \$objdir/pack/\$idx" &&
@@ -149,7 +149,7 @@ test_expect_success 'corrupt idx not opened' '
        test_copy_bytes 1064 <backup-$idx >$objdir/pack/$idx &&
 
        git -c core.multiPackIndex=true rev-list --objects --all 2>err &&
-       test_must_be_empty err
+       grep "index unavailable" err
 '
 
 test_expect_success 'add more objects' '
@@ -755,4 +755,30 @@ test_expect_success 'repack --batch-size=<large> repacks everything' '
        )
 '
 
+test_expect_success 'load reverse index when missing .idx, .pack' '
+       git init repo &&
+       test_when_finished "rm -fr repo" &&
+       (
+               cd repo &&
+
+               git config core.multiPackIndex true &&
+
+               test_commit base &&
+               git repack -ad &&
+               git multi-pack-index write &&
+
+               git rev-parse HEAD >tip &&
+               pack=$(ls .git/objects/pack/pack-*.pack) &&
+               idx=$(ls .git/objects/pack/pack-*.idx) &&
+
+               mv $idx $idx.bak &&
+               git cat-file --batch-check="%(objectsize:disk)" <tip &&
+
+               mv $idx.bak $idx &&
+
+               mv $pack $pack.bak &&
+               git cat-file --batch-check="%(objectsize:disk)" <tip
+       )
+'
+
 test_done