[PATCH 1/3] object-store: factor out odb_loose_cache()

[René Scharfe]

Add and use a function for loading the entries if a loose object
subdirectory for a given object ID.  It frees callers from deriving the
fanout key; they can use the returned oid_array reference for lookups or
forward range scans.

Suggested-by: Jeff King <p...@peff.net>
Signed-off-by: Rene Scharfe <l....@web.de>
---
 object-store.h |  7 +++++++
 sha1-file.c    | 12 +++++++++---
 sha1-name.c    | 10 +++++-----
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/object-store.h b/object-store.h
index 60758efad8..7236c571c0 100644
--- a/object-store.h
+++ b/object-store.h
@@ -54,6 +54,13 @@ void add_to_alternates_memory(const char *dir);
  */
 void odb_load_loose_cache(struct object_directory *odb, int subdir_nr);
 
+/*
+ * Populate and return the loose object cache array corresponding to the
+ * given object ID.
+ */
+struct oid_array *odb_loose_cache(struct object_directory *odb,
+                                 const struct object_id *oid);
+
 struct packed_git {
        struct packed_git *next;
        struct list_head mru;
diff --git a/sha1-file.c b/sha1-file.c
index 5a272f70de..cb8583b634 100644
--- a/sha1-file.c
+++ b/sha1-file.c
@@ -924,7 +924,6 @@ static int open_sha1_file(struct repository *r,
 static int quick_has_loose(struct repository *r,
                           const unsigned char *sha1)
 {
-       int subdir_nr = sha1[0];
        struct object_id oid;
        struct object_directory *odb;
 
@@ -932,8 +931,7 @@ static int quick_has_loose(struct repository *r,
 
        prepare_alt_odb(r);
        for (odb = r->objects->odb; odb; odb = odb->next) {
-               odb_load_loose_cache(odb, subdir_nr);
-               if (oid_array_lookup(&odb->loose_objects_cache, &oid) >= 0)
+               if (oid_array_lookup(odb_loose_cache(odb, &oid), &oid) >= 0)
                        return 1;
        }
        return 0;
@@ -2152,6 +2150,14 @@ static int append_loose_object(const struct object_id 
*oid, const char *path,
        return 0;
 }
 
+struct oid_array *odb_loose_cache(struct object_directory *odb,
+                                 const struct object_id *oid)
+{
+       int subdir_nr = oid->hash[0];
+       odb_load_loose_cache(odb, subdir_nr);
+       return &odb->loose_objects_cache;
+}
+
 void odb_load_loose_cache(struct object_directory *odb, int subdir_nr)
 {
        struct strbuf buf = STRBUF_INIT;
diff --git a/sha1-name.c b/sha1-name.c
index b24502811b..a656481c6a 100644
--- a/sha1-name.c
+++ b/sha1-name.c
@@ -87,21 +87,21 @@ static int match_sha(unsigned, const unsigned char *, const 
unsigned char *);
 
 static void find_short_object_filename(struct disambiguate_state *ds)
 {
-       int subdir_nr = ds->bin_pfx.hash[0];
        struct object_directory *odb;
 
        for (odb = the_repository->objects->odb;
             odb && !ds->ambiguous;
             odb = odb->next) {
                int pos;
+               struct oid_array *loose_objects;
 
-               odb_load_loose_cache(odb, subdir_nr);
-               pos = oid_array_lookup(&odb->loose_objects_cache, &ds->bin_pfx);
+               loose_objects = odb_loose_cache(odb, &ds->bin_pfx);
+               pos = oid_array_lookup(loose_objects, &ds->bin_pfx);
                if (pos < 0)
                        pos = -1 - pos;
-               while (!ds->ambiguous && pos < odb->loose_objects_cache.nr) {
+               while (!ds->ambiguous && pos < loose_objects->nr) {
                        const struct object_id *oid;
-                       oid = odb->loose_objects_cache.oid + pos;
+                       oid = loose_objects->oid + pos;
                        if (!match_sha(ds->len, ds->bin_pfx.hash, oid->hash))
                                break;
                        update_candidates(ds, oid);
-- 
2.20.1