1 files changed, 46 insertions, 0 deletions
diff --git a/Annex/Version.hs b/Annex/Version.hs
new file mode 100644
index 000000000..e501dbf2e
--- /dev/null
+++ b/Annex/Version.hs
@@ -0,0 +1,46 @@
+{- git-annex repository versioning
+ -
+ - Copyright 2010 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Version where
+
+import Annex.Common
+import qualified Git
+import Config
+
+type Version = String
+
+defaultVersion :: Version
+defaultVersion = "3"
+
+supportedVersions :: [Version]
+supportedVersions = [defaultVersion]
+
+upgradableVersions :: [Version]
+upgradableVersions = ["0", "1", "2"]
+
+versionField :: String
+versionField = "annex.version"
+
+getVersion :: Annex (Maybe Version)
+getVersion = do
+	g <- gitRepo
+	let v = Git.configGet g versionField ""
+	if not $ null v
+		then return $ Just v
+		else return Nothing
+
+setVersion :: Annex ()
+setVersion = setConfig versionField defaultVersion
+
+checkVersion :: Version -> Annex ()
+checkVersion v
+	| v `elem` supportedVersions = return ()
+	| v `elem` upgradableVersions = err "Upgrade this repository: git-annex upgrade"
+	| otherwise = err "Upgrade git-annex."
+	where
+		err msg = error $ "Repository version " ++ v ++
+			" is not supported. " ++ msg