[PATCH v2 2/9] odb: allow `odb_find_source()` to fail

[Patrick Steinhardt <ps@pks.im>]

When trying to locate a source for an unknown object directory we will
die right away. In subsequent patches we will add new callsites though
that want to handle this situation gracefully instead.

Refactor the function to return a `NULL` pointer if the source could not
be found and adapt the callsites to die instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
---
 builtin/commit-graph.c | 4 ++++
 midx-write.c           | 2 ++
 odb.c                  | 2 --
 odb.h                  | 4 ++--
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 25018a0b9d..dc2c1a5432 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -102,6 +102,8 @@ static int graph_verify(int argc, const char **argv, const char *prefix,
 		flags |= COMMIT_GRAPH_WRITE_PROGRESS;
 
 	source = odb_find_source(the_repository->objects, opts.obj_dir);
+	if (!source)
+		die(_("could not find object directory matching %s"), opts.obj_dir);
 	graph_name = get_commit_graph_filename(source);
 	chain_name = get_commit_graph_chain_filename(source);
 	if (open_commit_graph(graph_name, &fd, &st))
@@ -290,6 +292,8 @@ static int graph_write(int argc, const char **argv, const char *prefix,
 		flags |= COMMIT_GRAPH_WRITE_BLOOM_FILTERS;
 
 	source = odb_find_source(the_repository->objects, opts.obj_dir);
+	if (!source)
+		die(_("could not find object directory matching %s"), opts.obj_dir);
 
 	if (opts.reachable) {
 		if (write_commit_graph_reachable(source, flags, &write_opts))
diff --git a/midx-write.c b/midx-write.c
index c1ae62d354..40580d8c73 100644
--- a/midx-write.c
+++ b/midx-write.c
@@ -917,6 +917,8 @@ static struct multi_pack_index *lookup_multi_pack_index(struct repository *r,
 							const char *object_dir)
 {
 	struct odb_source *source = odb_find_source(r->objects, object_dir);
+	if (!source)
+		die(_("could not find object directory matching %s"), object_dir);
 	return get_multi_pack_index(source);
 }
 
diff --git a/odb.c b/odb.c
index 1761a50840..61104b7cb8 100644
--- a/odb.c
+++ b/odb.c
@@ -464,8 +464,6 @@ struct odb_source *odb_find_source(struct object_database *odb, const char *obj_
 	free(obj_dir_real);
 	strbuf_release(&odb_path_real);
 
-	if (!source)
-		die(_("could not find object directory matching %s"), obj_dir);
 	return source;
 }
 
diff --git a/odb.h b/odb.h
index f9300439ba..d085e691f2 100644
--- a/odb.h
+++ b/odb.h
@@ -186,8 +186,8 @@ struct object_database *odb_new(struct repository *repo);
 void odb_clear(struct object_database *o);
 
 /*
- * Find source by its object directory path. Dies in case the source couldn't
- * be found.
+ * Find source by its object directory path. Returns a `NULL` pointer in case
+ * the source could not be found.
  */
 struct odb_source *odb_find_source(struct object_database *odb, const char *obj_dir);
 

-- 
2.51.0.rc0.215.g125493bb4a.dirty