refs: add a backend method structure

Add a `struct ref_storage_be` to represent types of reference stores. In
OO notation, this is the class, and will soon hold some class
methods (e.g., a factory to create new ref_store instances) and will
also serve as the vtable for ref_store instances of that type.

As yet, the backends cannot do anything.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: David Turner <dturner@twopensource.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/refs.c b/refs.c
index 256fef5da0fde1e3d9ab2dc81d22cad6d9db86cc..bee9a4571e2aac713d5e070f339ef810a2b933ef 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -9,6 +9,25 @@
 #include "object.h"
 #include "tag.h"
 
+/*
+ * List of all available backends
+ */
+static struct ref_storage_be *refs_backends = &refs_be_files;
+
+static struct ref_storage_be *find_ref_storage_backend(const char *name)
+{
+       struct ref_storage_be *be;
+       for (be = refs_backends; be; be = be->next)
+               if (!strcmp(be->name, name))
+                       return be;
+       return NULL;
+}
+
+int ref_storage_backend_exists(const char *name)
+{
+       return find_ref_storage_backend(name) != NULL;
+}
+
 /*
  * How to handle various characters in refnames:
  * 0: An acceptable character for refs

diff --git a/refs.h b/refs.h
index 442c1a5db8147262bf2894f3bc47b67683f838b6..52ea93b8c36cc64a60a0009a8619dae017effba8 100644 (file)
--- a/refs.h
+++ b/refs.h
@@ -544,4 +544,6 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
                  reflog_expiry_cleanup_fn cleanup_fn,
                  void *policy_cb_data);
 
+int ref_storage_backend_exists(const char *name);
+
 #endif /* REFS_H */

diff --git a/refs/files-backend.c b/refs/files-backend.c
index c229b56bd5d39dd1c5d4f4473d2cabf7ada3d39d..0102491b134e3afcddaa71edc2c3542c96496413 100644 (file)
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -4066,3 +4066,8 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
        unlock_ref(lock);
        return -1;
 }
+
+struct ref_storage_be refs_be_files = {
+       NULL,
+       "files"
+};

diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 0206e2b9597d055e04fcd0d8853c4ebf2c4988a1..2c9d134021cffca8f950a45baadd4af740273b34 100644 (file)
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -525,4 +525,12 @@ int do_for_each_ref_iterator(struct ref_iterator *iter,
 int read_raw_ref(const char *refname, unsigned char *sha1,
                 struct strbuf *referent, unsigned int *type);
 
+/* refs backends */
+struct ref_storage_be {
+       struct ref_storage_be *next;
+       const char *name;
+};
+
+extern struct ref_storage_be refs_be_files;
+
 #endif /* REFS_REFS_INTERNAL_H */