The `--missing` object option in rev-list currently works only with
missing blobs/trees. For missing commits the revision walker fails with
a fatal error.
Let's extend the functionality of `--missing` option to also support
commit objects. This is done by adding a `missing_objects` field to
`rev_info`. This field is an `oidset` to which we'll add the missing
commits as we encounter them. The revision walker will now continue the
traversal and call `show_commit()` even for missing commits. In rev-list
we can then check if the commit is a missing commit and call the
existing code for parsing `--missing` objects.
A scenario where this option would be used is to find the boundary
objects between different object directories. Consider a repository with
a main object directory (GIT_OBJECT_DIRECTORY) and one or more alternate
object directories (GIT_ALTERNATE_OBJECT_DIRECTORIES). In such a
repository, using the `--missing=print` option while disabling the
alternate object directory allows us to find the boundary objects
between the main and alternate object directory.
Helped-by: Patrick Steinhardt <ps@xxxxxx>
Helped-by: Junio C Hamano <gitster@xxxxxxxxx>
Signed-off-by: Karthik Nayak <karthik.188@xxxxxxxxx>
---
builtin/rev-list.c | 6 +++
list-objects.c | 3 ++
revision.c | 17 ++++++++-
revision.h | 4 ++
t/t6022-rev-list-missing.sh | 74 +++++++++++++++++++++++++++++++++++++
5 files changed, 102 insertions(+), 2 deletions(-)
create mode 100755 t/t6022-rev-list-missing.sh
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index 98542e8b3c..181353dcf5 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -149,6 +149,12 @@ static void show_commit(struct commit *commit, void *data)
display_progress(progress, ++progress_counter);
+ if (revs->do_not_die_on_missing_objects &&
+ oidset_contains(&revs->missing_commits, &commit->object.oid)) {
+ finish_object__ma(&commit->object);
+ return;
+ }
+
if (show_disk_usage)
total_disk_usage += get_object_disk_usage(&commit->object);
diff --git a/list-objects.c b/list-objects.c
index 47296dff2f..f4e1104b56 100644
--- a/list-objects.c
+++ b/list-objects.c
@@ -389,6 +389,9 @@ static void do_traverse(struct traversal_context *ctx)
*/
if (!ctx->revs->tree_objects)
; /* do not bother loading tree */
+ else if (ctx->revs->do_not_die_on_missing_objects &&
+ oidset_contains(&ctx->revs->missing_commits, &commit->object.oid))
+ ;
else if (repo_get_commit_tree(the_repository, commit)) {
struct tree *tree = repo_get_commit_tree(the_repository,
commit);
diff --git a/revision.c b/revision.c
index 219dc76716..738bacad08 100644
--- a/revision.c
+++ b/revision.c
@@ -6,6 +6,7 @@
#include "object-name.h"
#include "object-file.h"
#include "object-store-ll.h"
+#include "oidset.h"
#include "tag.h"
#include "blob.h"
#include "tree.h"
@@ -1112,6 +1113,9 @@ static int process_parents(struct rev_info *revs, struct commit *commit,
if (commit->object.flags & ADDED)
return 0;
+ if (revs->do_not_die_on_missing_objects &&
+ oidset_contains(&revs->missing_commits, &commit->object.oid))
+ return 0;
commit->object.flags |= ADDED;
if (revs->include_check &&
@@ -1168,7 +1172,8 @@ static int process_parents(struct rev_info *revs, struct commit *commit,
for (parent = commit->parents; parent; parent = parent->next) {
struct commit *p = parent->item;
int gently = revs->ignore_missing_links ||
- revs->exclude_promisor_objects;
+ revs->exclude_promisor_objects ||
+ revs->do_not_die_on_missing_objects;
if (repo_parse_commit_gently(revs->repo, p, gently) < 0) {
if (revs->exclude_promisor_objects &&
is_promisor_object(&p->object.oid)) {
@@ -1176,7 +1181,11 @@ static int process_parents(struct rev_info *revs, struct commit *commit,
break;
continue;
}
- return -1;
+
+ if (revs->do_not_die_on_missing_objects)
+ oidset_insert(&revs->missing_commits, &p->object.oid);
+ else
+ return -1; /* corrupt repository */
}
if (revs->sources) {
char **slot = revision_sources_at(revs->sources, p);
@@ -3109,6 +3118,7 @@ void release_revisions(struct rev_info *revs)
clear_decoration(&revs->merge_simplification, free);
clear_decoration(&revs->treesame, free);
line_log_free(revs);
+ oidset_clear(&revs->missing_commits);
}
static void add_child(struct rev_info *revs, struct commit *parent, struct commit *child)
@@ -3800,6 +3810,9 @@ int prepare_revision_walk(struct rev_info *revs)
FOR_EACH_OBJECT_PROMISOR_ONLY);
}
+ if (revs->do_not_die_on_missing_objects)
+ oidset_init(&revs->missing_commits, 0);
+
if (!revs->reflog_info)
prepare_to_use_bloom_filter(revs);
if (!revs->unsorted_input)
diff --git a/revision.h b/revision.h
index c73c92ef40..94c43138bc 100644
--- a/revision.h
+++ b/revision.h
@@ -4,6 +4,7 @@
#include "commit.h"
#include "grep.h"
#include "notes.h"
+#include "oidset.h"
#include "pretty.h"
#include "diff.h"
#include "commit-slab-decl.h"
@@ -373,6 +374,9 @@ struct rev_info {
/* Location where temporary objects for remerge-diff are written. */
struct tmp_objdir *remerge_objdir;
+
+ /* Missing commits to be tracked without failing traversal. */
+ struct oidset missing_commits;
};
/**
diff --git a/t/t6022-rev-list-missing.sh b/t/t6022-rev-list-missing.sh
new file mode 100755
index 0000000000..40265a4f66
--- /dev/null
+++ b/t/t6022-rev-list-missing.sh
@@ -0,0 +1,74 @@
+#!/bin/sh
+
+test_description='handling of missing objects in rev-list'
+
+TEST_PASSES_SANITIZE_LEAK=true
+. ./test-lib.sh
+
+# We setup the repository with two commits, this way HEAD is always
+# available and we can hide commit 1.
+test_expect_success 'create repository and alternate directory' '
+ test_commit 1 &&
+ test_commit 2 &&
+ test_commit 3
+'
+
+for obj in "HEAD~1" "HEAD~1^{tree}" "HEAD:1.t"
+do
+ test_expect_success "rev-list --missing=error fails with missing object $obj" '
+ oid="$(git rev-parse $obj)" &&
+ path=".git/objects/$(test_oid_to_path $oid)" &&
+
+ mv "$path" "$path.hidden" &&
+ test_when_finished "mv $path.hidden $path" &&
+
+ test_must_fail git rev-list --missing=error --objects \
+ --no-object-names HEAD
+ '
+done
+
+for obj in "HEAD~1" "HEAD~1^{tree}" "HEAD:1.t"
+do
+ for action in "allow-any" "print"
+ do
+ test_expect_success "rev-list --missing=$action with missing $obj" '
+ oid="$(git rev-parse $obj)" &&
+ path=".git/objects/$(test_oid_to_path $oid)" &&
+
+ # Before the object is made missing, we use rev-list to
+ # get the expected oids.
+ git rev-list --objects --no-object-names \
+ HEAD ^$obj >expect.raw &&
+
+ # Blobs are shared by all commits, so evethough a commit/tree
+ # might be skipped, its blob must be accounted for.
+ if [ $obj != "HEAD:1.t" ]; then
+ echo $(git rev-parse HEAD:1.t) >>expect.raw &&
+ echo $(git rev-parse HEAD:2.t) >>expect.raw
+ fi &&
+
+ mv "$path" "$path.hidden" &&
+ test_when_finished "mv $path.hidden $path" &&
+
+ git rev-list --missing=$action --objects --no-object-names \
+ HEAD >actual.raw &&
+
+ # When the action is to print, we should also add the missing
+ # oid to the expect list.
+ case $action in
+ allow-any)
+ ;;
+ print)
+ grep ?$oid actual.raw &&
+ echo ?$oid >>expect.raw
+ ;;
+ esac &&
+
+ sort actual.raw >actual &&
+ sort expect.raw >expect &&
+ test_cmp expect actual
+ '
+ done
+done
+
+test_done
--
2.42.0
