lib/core: introduce two new object types for split xattrs

This adds two new object types for storing xattrs separately from
content objects.

`.file-xattrs` are regular files storing xattrs content, encoded as
GVariant. Each object is keyed by the checksum of its content, allowing
for multiple references.

`.file-xattrs-link` are hardlinks which are associated to file objects.
Each object is keyed by the same checksum of the corresponding file
object. The target of the hardlink is an existing file-xattrs object.
In case of reaching the limit of too many links, this object could be
a plain file too.

diff --git a/src/libostree/ostree-core.c b/src/libostree/ostree-core.c
index 0671ed355fa83666fff7b0bf7871aa0cab0dbef4..2ff720862e2034bd7ebb6d1e8f2023a1739d019b 100644 (file)
--- a/src/libostree/ostree-core.c
+++ b/src/libostree/ostree-core.c
@@ -1228,6 +1228,10 @@ ostree_object_type_to_string (OstreeObjectType objtype)
       return "commitmeta";
     case OSTREE_OBJECT_TYPE_PAYLOAD_LINK:
       return "payload-link";
+    case OSTREE_OBJECT_TYPE_FILE_XATTRS:
+      return "file-xattrs";
+    case OSTREE_OBJECT_TYPE_FILE_XATTRS_LINK:
+      return "file-xattrs-link";
     default:
       g_assert_not_reached ();
       return NULL;
@@ -1257,6 +1261,10 @@ ostree_object_type_from_string (const char *str)
     return OSTREE_OBJECT_TYPE_COMMIT_META;
   else if (!strcmp (str, "payload-link"))
     return OSTREE_OBJECT_TYPE_PAYLOAD_LINK;
+  else if (!strcmp (str, "file-xattrs"))
+    return OSTREE_OBJECT_TYPE_FILE_XATTRS;
+  else if (!strcmp (str, "file-xattrs-link"))
+    return OSTREE_OBJECT_TYPE_FILE_XATTRS_LINK;
   g_assert_not_reached ();
   return 0;
 }
@@ -2141,6 +2149,8 @@ _ostree_validate_structureof_metadata (OstreeObjectType objtype,
       /* TODO */
       break;
     case OSTREE_OBJECT_TYPE_FILE:
+    case OSTREE_OBJECT_TYPE_FILE_XATTRS:
+    case OSTREE_OBJECT_TYPE_FILE_XATTRS_LINK:
       g_assert_not_reached ();
       break;
     }

diff --git a/src/libostree/ostree-core.h b/src/libostree/ostree-core.h
index 48a75f92a5359cf9224c0c0a63b1b3927a77e0ce..638c40ac1b480d87dbd08475c595f1400f708d7a 100644 (file)
--- a/src/libostree/ostree-core.h
+++ b/src/libostree/ostree-core.h
@@ -67,6 +67,8 @@ G_BEGIN_DECLS
  * @OSTREE_OBJECT_TYPE_TOMBSTONE_COMMIT: Toplevel object, refers to a deleted commit
  * @OSTREE_OBJECT_TYPE_COMMIT_META: Detached metadata for a commit
  * @OSTREE_OBJECT_TYPE_PAYLOAD_LINK: Symlink to a .file given its checksum on the payload only.
+ * @OSTREE_OBJECT_TYPE_FILE_XATTRS: Detached xattrs content, for 'bare-split-xattrs' mode.
+ * @OSTREE_OBJECT_TYPE_FILE_XATTRS_LINK: Hardlink to a .file-xattrs given the checksum of its .file object.
  *
  * Enumeration for core object types; %OSTREE_OBJECT_TYPE_FILE is for
  * content, the other types are metadata.
@@ -78,7 +80,9 @@ typedef enum {
   OSTREE_OBJECT_TYPE_COMMIT = 4,              /* .commit */
   OSTREE_OBJECT_TYPE_TOMBSTONE_COMMIT = 5,    /* .commit-tombstone */
   OSTREE_OBJECT_TYPE_COMMIT_META = 6,         /* .commitmeta */
-  OSTREE_OBJECT_TYPE_PAYLOAD_LINK = 7,         /* .payload-link */
+  OSTREE_OBJECT_TYPE_PAYLOAD_LINK = 7,        /* .payload-link */
+  OSTREE_OBJECT_TYPE_FILE_XATTRS = 8,         /* .file-xattrs */
+  OSTREE_OBJECT_TYPE_FILE_XATTRS_LINK = 9,    /* .file-xattrs-link */
 } OstreeObjectType;
 
 /**
@@ -94,7 +98,7 @@ typedef enum {
  *
  * Last valid object type; use this to validate ranges.
  */
-#define OSTREE_OBJECT_TYPE_LAST OSTREE_OBJECT_TYPE_PAYLOAD_LINK
+#define OSTREE_OBJECT_TYPE_LAST OSTREE_OBJECT_TYPE_FILE_XATTRS_LINK
 
 /**
  * OSTREE_DIRMETA_GVARIANT_FORMAT: