git-annex/Database/Init.hs
Joey Hess 40ecf58d4b
update licenses from GPL to AGPL
This does not change the overall license of the git-annex program, which
was already AGPL due to a number of sources files being AGPL already.

Legally speaking, I'm adding a new license under which these files are
now available; I already released their current contents under the GPL
license. Now they're dual licensed GPL and AGPL. However, I intend
for all my future changes to these files to only be released under the
AGPL license, and I won't be tracking the dual licensing status, so I'm
simply changing the license statement to say it's AGPL.

(In some cases, others wrote parts of the code of a file and released it
under the GPL; but in all cases I have contributed a significant portion
of the code in each file and it's that code that is getting the AGPL
license; the GPL license of other contributors allows combining with
AGPL code.)
2019-03-13 15:48:14 -04:00

76 lines
2.2 KiB
Haskell

{- Persistent sqlite database initialization
-
- Copyright 2015-2018 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE CPP #-}
module Database.Init where
import Annex.Common
import Annex.Perms
import Utility.FileMode
import Database.Persist.Sqlite
import Control.Monad.IO.Class (liftIO)
import qualified Data.Text as T
#if MIN_VERSION_persistent_sqlite(2,6,2)
import Lens.Micro
#else
import qualified Database.Sqlite as Sqlite
#endif
{- Ensures that the database is freshly initialized. Deletes any
- existing database. Pass the migration action for the database.
-
- The permissions of the database are set based on the
- core.sharedRepository setting. Setting these permissions on the main db
- file causes Sqlite to always use the same permissions for additional
- files it writes later on
-}
initDb :: FilePath -> SqlPersistM () -> Annex ()
initDb db migration = do
let dbdir = takeDirectory db
let tmpdbdir = dbdir ++ ".tmp"
let tmpdb = tmpdbdir </> "db"
let tdb = T.pack tmpdb
liftIO $ do
createDirectoryIfMissing True tmpdbdir
#if MIN_VERSION_persistent_sqlite(2,6,2)
runSqliteInfo (enableWAL tdb) migration
#else
enableWAL tdb
runSqlite tdb migration
#endif
setAnnexDirPerm tmpdbdir
-- Work around sqlite bug that prevents it from honoring
-- less restrictive umasks.
liftIO $ setFileMode tmpdb =<< defaultFileMode
setAnnexFilePerm tmpdb
liftIO $ do
void $ tryIO $ removeDirectoryRecursive dbdir
rename tmpdbdir dbdir
{- Make sure that the database uses WAL mode, to prevent readers
- from blocking writers, and prevent a writer from blocking readers.
-
- This is the default in recent persistent-sqlite versions, but
- force it on just in case.
-
- Note that once WAL mode is enabled, it will persist whenever the
- database is opened. -}
#if MIN_VERSION_persistent_sqlite(2,6,2)
enableWAL :: T.Text -> SqliteConnectionInfo
enableWAL db = over walEnabled (const True) $
mkSqliteConnectionInfo db
#else
enableWAL :: T.Text -> IO ()
enableWAL db = do
conn <- Sqlite.open db
stmt <- Sqlite.prepare conn (T.pack "PRAGMA journal_mode=WAL;")
void $ Sqlite.step stmt
void $ Sqlite.finalize stmt
Sqlite.close conn
#endif