[PATCH v2 03/29] packed_ref_store: new struct

[Michael Haggerty]

Start extracting the packed-refs-related data structures into a new
class, `packed_ref_store`. It doesn't yet implement `ref_store`, but
it will.

Signed-off-by: Michael Haggerty <mhag...@alum.mit.edu>
---
 refs/files-backend.c | 42 +++++++++++++++++++++++++++++++++---------
 1 file changed, 33 insertions(+), 9 deletions(-)

diff --git a/refs/files-backend.c b/refs/files-backend.c
index 87cecde231..2efb71cee9 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -47,6 +47,28 @@ struct packed_ref_cache {
        struct stat_validity validity;
 };
 
+/*
+ * A container for `packed-refs`-related data. It is not (yet) a
+ * `ref_store`.
+ */
+struct packed_ref_store {
+       unsigned int store_flags;
+
+       /*
+        * A cache of the values read from the `packed-refs` file, if
+        * it might still be current; otherwise, NULL.
+        */
+       struct packed_ref_cache *cache;
+};
+
+static struct packed_ref_store *packed_ref_store_create(unsigned int 
store_flags)
+{
+       struct packed_ref_store *refs = xcalloc(1, sizeof(*refs));
+
+       refs->store_flags = store_flags;
+       return refs;
+}
+
 /*
  * Future: need to be in "struct repository"
  * when doing a full libification.
@@ -60,13 +82,14 @@ struct files_ref_store {
        char *packed_refs_path;
 
        struct ref_cache *loose;
-       struct packed_ref_cache *packed;
 
        /*
         * Lock used for the "packed-refs" file. Note that this (and
         * thus the enclosing `files_ref_store`) must not be freed.
         */
        struct lock_file packed_refs_lock;
+
+       struct packed_ref_store *packed_ref_store;
 };
 
 /*
@@ -95,12 +118,12 @@ static int release_packed_ref_cache(struct 
packed_ref_cache *packed_refs)
 
 static void clear_packed_ref_cache(struct files_ref_store *refs)
 {
-       if (refs->packed) {
-               struct packed_ref_cache *packed_refs = refs->packed;
+       if (refs->packed_ref_store->cache) {
+               struct packed_ref_cache *packed_refs = 
refs->packed_ref_store->cache;
 
                if (is_lock_file_locked(&refs->packed_refs_lock))
                        die("BUG: packed-ref cache cleared while locked");
-               refs->packed = NULL;
+               refs->packed_ref_store->cache = NULL;
                release_packed_ref_cache(packed_refs);
        }
 }
@@ -132,6 +155,7 @@ static struct ref_store *files_ref_store_create(const char 
*gitdir,
        refs->gitcommondir = strbuf_detach(&sb, NULL);
        strbuf_addf(&sb, "%s/packed-refs", refs->gitcommondir);
        refs->packed_refs_path = strbuf_detach(&sb, NULL);
+       refs->packed_ref_store = packed_ref_store_create(flags);
 
        return ref_store;
 }
@@ -375,8 +399,8 @@ static void files_ref_path(struct files_ref_store *refs,
  */
 static void validate_packed_ref_cache(struct files_ref_store *refs)
 {
-       if (refs->packed &&
-           !stat_validity_check(&refs->packed->validity,
+       if (refs->packed_ref_store->cache &&
+           !stat_validity_check(&refs->packed_ref_store->cache->validity,
                                 files_packed_refs_path(refs)))
                clear_packed_ref_cache(refs);
 }
@@ -396,10 +420,10 @@ static struct packed_ref_cache 
*get_packed_ref_cache(struct files_ref_store *ref
        if (!is_lock_file_locked(&refs->packed_refs_lock))
                validate_packed_ref_cache(refs);
 
-       if (!refs->packed)
-               refs->packed = read_packed_refs(packed_refs_file);
+       if (!refs->packed_ref_store->cache)
+               refs->packed_ref_store->cache = 
read_packed_refs(packed_refs_file);
 
-       return refs->packed;
+       return refs->packed_ref_store->cache;
 }
 
 static struct ref_dir *get_packed_ref_dir(struct packed_ref_cache 
*packed_ref_cache)
-- 
2.11.0