git-annex (5.20140402) unstable; urgency=medium

  * unannex, uninit: Avoid committing after every file is unannexed,
    for massive speedup.
  * --notify-finish switch will cause desktop notifications after each
    file upload/download/drop completes
    (using the dbus Desktop Notifications Specification)
  * --notify-start switch will show desktop notifications when each
    file upload/download starts.
  * webapp: Automatically install Nautilus integration scripts
    to get and drop files.
  * tahoe: Pass -d parameter before subcommand; putting it after
    the subcommand no longer works with tahoe-lafs version 1.10.
    (Thanks, Alberto Berti)
  * forget --drop-dead: Avoid removing the dead remote from the trust.log,
    so that if git remotes for it still exist anywhere, git annex info
    will still know it's dead and not show it.
  * git-annex-shell: Make configlist automatically initialize
    a remote git repository, as long as a git-annex branch has
    been pushed to it, to simplify setup of remote git repositories,
    including via gitolite.
  * add --include-dotfiles: New option, perhaps useful for backups.
  * Version 5.20140227 broke creation of glacier repositories,
    not including the datacenter and vault in their configuration.
    This bug is fixed, but glacier repositories set up with the broken
    version of git-annex need to have the datacenter and vault set
    in order to be usable. This can be done using git annex enableremote
    to add the missing settings. For details, see
    http://git-annex.branchable.com/bugs/problems_with_glacier/
  * Added required content configuration.
  * assistant: Improve ssh authorized keys line generated in local pairing
    or for a remote ssh server to set environment variables in an
    alternative way that works with the non-POSIX fish shell, as well
    as POSIX shells.

# imported from the archive

1 files changed, 124 insertions, 0 deletions

diff --git a/Annex/Drop.hs b/Annex/Drop.hs
new file mode 100644
index 000000000..71263dc61
--- /dev/null
+++ b/Annex/Drop.hs
@@ -0,0 +1,124 @@
+{- dropping of unwanted content
+ -
+ - Copyright 2012-2014 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Drop where
+
+import Common.Annex
+import Logs.Trust
+import Config.NumCopies
+import Types.Remote (uuid)
+import Types.Key (key2file)
+import qualified Remote
+import qualified Command.Drop
+import Command
+import Annex.Wanted
+import Annex.Exception
+import Config
+import Annex.Content.Direct
+
+import qualified Data.Set as S
+import System.Log.Logger (debugM)
+
+type Reason = String
+
+{- Drop a key from local and/or remote when allowed by the preferred content
+ - and numcopies settings.
+ -
+ - The UUIDs are ones where the content is believed to be present.
+ - The Remote list can include other remotes that do not have the content;
+ - only ones that match the UUIDs will be dropped from.
+ - If allowed to drop fromhere, that drop will be tried first.
+ -
+ - A remote can be specified that is known to have the key. This can be
+ - used an an optimisation when eg, a key has just been uploaded to a
+ - remote.
+ -
+ - In direct mode, all associated files are checked, and only if all
+ - of them are unwanted are they dropped.
+ -
+ - The runner is used to run commands, and so can be either callCommand
+ - or commandAction.
+ -}
+handleDropsFrom :: [UUID] -> [Remote] -> Reason -> Bool -> Key -> AssociatedFile -> Maybe Remote -> CommandActionRunner -> Annex ()
+handleDropsFrom locs rs reason fromhere key afile knownpresentremote runner = do
+	fs <- ifM isDirect
+		( do
+			l <- associatedFilesRelative key
+			return $ if null l
+				then maybeToList afile
+				else l
+		, return $ maybeToList afile
+		)
+	n <- getcopies fs
+	if fromhere && checkcopies n Nothing
+		then go fs rs =<< dropl fs n
+		else go fs rs n
+  where
+	getcopies fs = do
+		(untrusted, have) <- trustPartition UnTrusted locs
+		numcopies <- if null fs
+			then getNumCopies
+			else maximum <$> mapM getFileNumCopies fs
+		return (NumCopies (length have), numcopies, S.fromList untrusted)
+
+	{- Check that we have enough copies still to drop the content.
+	 - When the remote being dropped from is untrusted, it was not
+	 - counted as a copy, so having only numcopies suffices. Otherwise,
+	 - we need more than numcopies to safely drop. -}
+	checkcopies (have, numcopies, _untrusted) Nothing = have > numcopies
+	checkcopies (have, numcopies, untrusted) (Just u)
+		| S.member u untrusted = have >= numcopies
+		| otherwise = have > numcopies
+	
+	decrcopies (have, numcopies, untrusted) Nothing =
+		(NumCopies (fromNumCopies have - 1), numcopies, untrusted)
+	decrcopies v@(_have, _numcopies, untrusted) (Just u)
+		| S.member u untrusted = v
+		| otherwise = decrcopies v Nothing
+
+	go _ [] _ = noop
+	go fs (r:rest) n
+		| uuid r `S.notMember` slocs = go fs rest n
+		| checkcopies n (Just $ Remote.uuid r) =
+			dropr fs r n >>= go fs rest
+		| otherwise = noop
+
+	checkdrop fs n u a
+		| null fs = check $ -- no associated files; unused content
+			wantDrop True u (Just key) Nothing
+		| otherwise = check $
+			allM (wantDrop True u (Just key) . Just) fs
+		where
+			check c = ifM c
+				( dodrop n u a
+				, return n
+				)
+
+	dodrop n@(have, numcopies, _untrusted) u a = 
+		ifM (safely $ runner $ a numcopies)
+			( do
+				liftIO $ debugM "drop" $ unwords
+					[ "dropped"
+					, fromMaybe (key2file key) afile
+					, "(from " ++ maybe "here" show u ++ ")"
+					, "(copies now " ++ show (fromNumCopies have - 1) ++ ")"
+					, ": " ++ reason
+					]
+				return $ decrcopies n u
+			, return n
+			)
+
+	dropl fs n = checkdrop fs n Nothing $ \numcopies ->
+		Command.Drop.startLocal afile numcopies key knownpresentremote
+
+	dropr fs r n  = checkdrop fs n (Just $ Remote.uuid r) $ \numcopies ->
+		Command.Drop.startRemote afile numcopies key r
+
+	slocs = S.fromList locs
+	
+	safely a = either (const False) id <$> tryAnnex a
+