read_packed_refs(): do more of the work of reading packed refs

Teach `read_packed_refs()` to also

* Allocate and initialize the new `packed_ref_cache`
* Open and close the `packed-refs` file
* Update the `validity` field of the new object

This decreases the coupling between `packed_refs_cache` and
`files_ref_store` by a little bit.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/refs/files-backend.c b/refs/files-backend.c
index c4bc9550d3154ed7fb64aa563888e8a5f9c42dcd..b4fa745cd7058b2760f3bfb89fd5c1ee736ebc93 100644 (file)
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -209,7 +209,9 @@ static const char *parse_ref_line(struct strbuf *line, struct object_id *oid)
 }
 
 /*
- * Read f, which is a packed-refs file, into dir.
+ * Read from `packed_refs_file` into a newly-allocated
+ * `packed_ref_cache` and return it. The return value will already
+ * have its reference count incremented.
  *
  * A comment line of the form "# pack-refs with: " may contain zero or
  * more traits. We interpret the traits as follows:
@@ -235,12 +237,26 @@ static const char *parse_ref_line(struct strbuf *line, struct object_id *oid)
  *      compatibility with older clients, but we do not require it
  *      (i.e., "peeled" is a no-op if "fully-peeled" is set).
  */
-static void read_packed_refs(FILE *f, struct ref_dir *dir)
+static struct packed_ref_cache *read_packed_refs(const char *packed_refs_file)
 {
+       FILE *f;
+       struct packed_ref_cache *packed_refs = xcalloc(1, sizeof(*packed_refs));
        struct ref_entry *last = NULL;
        struct strbuf line = STRBUF_INIT;
        enum { PEELED_NONE, PEELED_TAGS, PEELED_FULLY } peeled = PEELED_NONE;
+       struct ref_dir *dir;
 
+       acquire_packed_ref_cache(packed_refs);
+       packed_refs->cache = create_ref_cache(NULL, NULL);
+       packed_refs->cache->root->flag &= ~REF_INCOMPLETE;
+
+       f = fopen(packed_refs_file, "r");
+       if (!f)
+               return packed_refs;
+
+       stat_validity_update(&packed_refs->validity, fileno(f));
+
+       dir = get_ref_dir(packed_refs->cache->root);
        while (strbuf_getwholeline(&line, f, '\n') != EOF) {
                struct object_id oid;
                const char *refname;
@@ -287,7 +303,10 @@ static void read_packed_refs(FILE *f, struct ref_dir *dir)
                }
        }
 
+       fclose(f);
        strbuf_release(&line);
+
+       return packed_refs;
 }
 
 static const char *files_packed_refs_path(struct files_ref_store *refs)
@@ -357,20 +376,9 @@ static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *ref
            !stat_validity_check(&refs->packed->validity, packed_refs_file))
                clear_packed_ref_cache(refs);
 
-       if (!refs->packed) {
-               FILE *f;
-
-               refs->packed = xcalloc(1, sizeof(*refs->packed));
-               acquire_packed_ref_cache(refs->packed);
-               refs->packed->cache = create_ref_cache(&refs->base, NULL);
-               refs->packed->cache->root->flag &= ~REF_INCOMPLETE;
-               f = fopen(packed_refs_file, "r");
-               if (f) {
-                       stat_validity_update(&refs->packed->validity, fileno(f));
-                       read_packed_refs(f, get_ref_dir(refs->packed->cache->root));
-                       fclose(f);
-               }
-       }
+       if (!refs->packed)
+               refs->packed = read_packed_refs(packed_refs_file);
+
        return refs->packed;
 }
 

diff --git a/refs/ref-cache.h b/refs/ref-cache.h
index 1f65e2f9ed2c8dc742ba25f53c0be18b0c50581e..fbfee7ce79417983f6b972ec1e6de025f5d443f5 100644 (file)
--- a/refs/ref-cache.h
+++ b/refs/ref-cache.h
@@ -194,7 +194,8 @@ struct ref_entry *create_ref_entry(const char *refname,
  * function called to fill in incomplete directories in the
  * `ref_cache` when they are accessed. If it is NULL, then the whole
  * `ref_cache` must be filled (including clearing its directories'
- * `REF_INCOMPLETE` bits) before it is used.
+ * `REF_INCOMPLETE` bits) before it is used, and `refs` can be NULL,
+ * too.
  */
 struct ref_cache *create_ref_cache(struct ref_store *refs,
                                   fill_ref_dir_fn *fill_ref_dir);