cabal-install-3.14.1.0: src/Distribution/Client/IndexUtils.hs
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE CPP #-}
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE ScopedTypeVariables #-}
-----------------------------------------------------------------------------
-----------------------------------------------------------------------------
-- |
-- Module : Distribution.Client.IndexUtils
-- Copyright : (c) Duncan Coutts 2008
-- License : BSD-like
--
-- Maintainer : duncan@community.haskell.org
-- Stability : provisional
-- Portability : portable
--
-- Extra utils related to the package indexes.
module Distribution.Client.IndexUtils
( getIndexFileAge
, getInstalledPackages
, indexBaseName
, Configure.getInstalledPackagesMonitorFiles
, getSourcePackages
, getSourcePackagesMonitorFiles
, TotalIndexState
, getSourcePackagesAtIndexState
, ActiveRepos
, filterSkippedActiveRepos
, Index (..)
, RepoIndexState (..)
, PackageEntry (..)
, parsePackageIndex
, updateRepoIndexCache
, updatePackageIndexCacheFile
, writeIndexTimestamp
, currentIndexTimestamp
, BuildTreeRefType (..)
, refTypeFromTypeCode
, typeCodeFromRefType
-- * preferred-versions utilities
, preferredVersions
, isPreferredVersions
, parsePreferredVersionsWarnings
, PreferredVersionsParseError (..)
) where
import Distribution.Client.Compat.Prelude
import Prelude ()
import qualified Codec.Archive.Tar as Tar
import qualified Codec.Archive.Tar.Entry as Tar
import qualified Codec.Archive.Tar.Index as Tar
import Distribution.Client.IndexUtils.ActiveRepos
import Distribution.Client.IndexUtils.IndexState
import Distribution.Client.IndexUtils.Timestamp
import qualified Distribution.Client.Tar as Tar
import Distribution.Client.Types
import Distribution.Parsec (simpleParsecBS)
import Distribution.Verbosity
import Distribution.Client.Setup
( RepoContext (..)
)
import Distribution.Package
( Package (..)
, PackageId
, PackageIdentifier (..)
, mkPackageName
, packageName
, packageVersion
)
import Distribution.PackageDescription
( GenericPackageDescription (..)
, PackageDescription (..)
, emptyPackageDescription
)
import Distribution.Simple.Compiler
import qualified Distribution.Simple.Configure as Configure
( getInstalledPackages
, getInstalledPackagesMonitorFiles
)
import Distribution.Simple.PackageIndex (InstalledPackageIndex)
import Distribution.Simple.Program
( ProgramDb
)
import Distribution.Simple.Utils
( createDirectoryIfMissingVerbose
, dieWithException
, fromUTF8LBS
, info
, warn
)
import Distribution.Types.Dependency
import Distribution.Types.PackageName (PackageName)
import Distribution.Version
( Version
, VersionRange
, intersectVersionRanges
, mkVersion
)
import Distribution.PackageDescription.Parsec
( parseGenericPackageDescription
, parseGenericPackageDescriptionMaybe
)
import qualified Distribution.PackageDescription.Parsec as PackageDesc.Parse
import Distribution.Solver.Types.PackageIndex (PackageIndex)
import qualified Distribution.Solver.Types.PackageIndex as PackageIndex
import Distribution.Solver.Types.SourcePackage
import qualified Codec.Compression.GZip as GZip
import Control.Exception
import qualified Data.ByteString.Char8 as BSS
import Data.ByteString.Lazy (ByteString)
import qualified Data.ByteString.Lazy as BS
import Data.Either
( rights
)
import Data.List (stripPrefix)
import qualified Data.Map as Map
import qualified Data.Set as Set
import Distribution.Client.GZipUtils (maybeDecompress)
import Distribution.Client.Utils
( byteStringToFilePath
, tryReadAddSourcePackageDesc
)
import Distribution.Compat.Directory (listDirectory)
import Distribution.Compat.Time (getFileAge, getModTime)
import Distribution.Utils.Generic (fstOf3)
import Distribution.Utils.Structured (Structured (..), nominalStructure, structuredDecodeFileOrFail, structuredEncodeFile)
import System.Directory (doesDirectoryExist, doesFileExist)
import System.FilePath
( normalise
, splitDirectories
, takeDirectory
, takeExtension
, takeFileName
, (<.>)
, (</>)
)
import qualified System.FilePath as FilePath
import System.IO
import System.IO.Error (isDoesNotExistError)
import System.IO.Unsafe (unsafeInterleaveIO)
import Distribution.Client.Errors
import qualified Hackage.Security.Client as Sec
import qualified Hackage.Security.Util.Some as Sec
-- | Reduced-verbosity version of 'Configure.getInstalledPackages'
getInstalledPackages
:: Verbosity
-> Compiler
-> PackageDBStackCWD
-> ProgramDb
-> IO InstalledPackageIndex
getInstalledPackages verbosity comp packageDbs progdb =
Configure.getInstalledPackages verbosity' comp Nothing (coercePackageDBStack packageDbs) progdb
where
verbosity' = lessVerbose verbosity
-- | Get filename base (i.e. without file extension) for index-related files
--
-- /Secure/ cabal repositories use a new extended & incremental
-- @01-index.tar@. In order to avoid issues resulting from clobbering
-- new/old-style index data, we save them locally to different names.
--
-- Example: Use @indexBaseName repo <.> "tar.gz"@ to compute the 'FilePath' of the
-- @00-index.tar.gz@/@01-index.tar.gz@ file.
indexBaseName :: Repo -> FilePath
indexBaseName repo = repoLocalDir repo </> fn
where
fn = case repo of
RepoSecure{} -> "01-index"
RepoRemote{} -> "00-index"
RepoLocalNoIndex{} -> "noindex"
------------------------------------------------------------------------
-- Reading the source package index
--
-- Note: 'data IndexState' is defined in
-- "Distribution.Client.IndexUtils.Timestamp" to avoid import cycles
-- | 'IndexStateInfo' contains meta-information about the resulting
-- filtered 'Cache' 'after applying 'filterCache' according to a
-- requested 'IndexState'.
data IndexStateInfo = IndexStateInfo
{ isiMaxTime :: !Timestamp
-- ^ 'Timestamp' of maximum/latest 'Timestamp' in the current
-- filtered view of the cache.
--
-- The following property holds
--
-- > filterCache (IndexState (isiMaxTime isi)) cache == (cache, isi)
, isiHeadTime :: !Timestamp
-- ^ 'Timestamp' equivalent to 'IndexStateHead', i.e. the latest
-- known 'Timestamp'; 'isiHeadTime' is always greater or equal to
-- 'isiMaxTime'.
}
emptyStateInfo :: IndexStateInfo
emptyStateInfo = IndexStateInfo NoTimestamp NoTimestamp
-- | Filters a 'Cache' according to an 'IndexState'
-- specification. Also returns 'IndexStateInfo' describing the
-- resulting index cache.
--
-- Note: 'filterCache' is idempotent in the 'Cache' value
filterCache :: RepoIndexState -> Cache -> (Cache, IndexStateInfo)
filterCache IndexStateHead cache = (cache, IndexStateInfo{..})
where
isiMaxTime = cacheHeadTs cache
isiHeadTime = cacheHeadTs cache
filterCache (IndexStateTime ts0) cache0 = (cache, IndexStateInfo{..})
where
cache = Cache{cacheEntries = ents, cacheHeadTs = isiMaxTime}
isiHeadTime = cacheHeadTs cache0
isiMaxTime = maximumTimestamp (map cacheEntryTimestamp ents)
ents = filter ((<= ts0) . cacheEntryTimestamp) (cacheEntries cache0)
-- | Read a repository index from disk, from the local files specified by
-- a list of 'Repo's.
--
-- All the 'SourcePackage's are marked as having come from the appropriate
-- 'Repo'.
--
-- This is a higher level wrapper used internally in cabal-install.
getSourcePackages :: Verbosity -> RepoContext -> IO SourcePackageDb
getSourcePackages verbosity repoCtxt =
fstOf3 <$> getSourcePackagesAtIndexState verbosity repoCtxt Nothing Nothing
-- | Variant of 'getSourcePackages' which allows getting the source
-- packages at a particular 'IndexState'.
--
-- Current choices are either the latest (aka HEAD), or the index as
-- it was at a particular time.
--
-- Returns also the total index where repositories'
-- RepoIndexState's are not HEAD. This is used in v2-freeze.
getSourcePackagesAtIndexState
:: Verbosity
-> RepoContext
-> Maybe TotalIndexState
-> Maybe ActiveRepos
-> IO (SourcePackageDb, TotalIndexState, ActiveRepos)
getSourcePackagesAtIndexState verbosity repoCtxt _ _
| null (repoContextRepos repoCtxt) = do
-- In the test suite, we routinely don't have any remote package
-- servers, so don't bleat about it
warn (verboseUnmarkOutput verbosity) $
"No remote package servers have been specified. Usually "
++ "you would have one specified in the config file."
return
( SourcePackageDb
{ packageIndex = mempty
, packagePreferences = mempty
}
, headTotalIndexState
, ActiveRepos []
)
getSourcePackagesAtIndexState verbosity repoCtxt mb_idxState mb_activeRepos = do
let describeState IndexStateHead = "most recent state"
describeState (IndexStateTime time) = "historical state as of " ++ prettyShow time
pkgss <- for (repoContextRepos repoCtxt) $ \r -> do
let rname :: RepoName
rname = repoName r
info verbosity ("Reading available packages of " ++ unRepoName rname ++ "...")
idxState <- case mb_idxState of
Just totalIdxState -> do
let idxState = lookupIndexState rname totalIdxState
info verbosity $
"Using "
++ describeState idxState
++ " as explicitly requested (via command line / project configuration)"
return idxState
Nothing -> do
mb_idxState' <- readIndexTimestamp verbosity (RepoIndex repoCtxt r)
case mb_idxState' of
Nothing -> do
info verbosity "Using most recent state (could not read timestamp file)"
return IndexStateHead
Just idxState -> do
info verbosity $
"Using "
++ describeState idxState
++ " specified from most recent cabal update"
return idxState
unless (idxState == IndexStateHead) $
case r of
RepoLocalNoIndex{} -> warn verbosity "index-state ignored for file+noindex repositories"
RepoRemote{} -> warn verbosity ("index-state ignored for old-format (remote repository '" ++ unRepoName rname ++ "')")
RepoSecure{} -> pure ()
let idxState' = case r of
RepoSecure{} -> idxState
_ -> IndexStateHead
(pis, deps, isi) <- readRepoIndex verbosity repoCtxt r idxState'
case idxState' of
IndexStateHead -> do
info verbosity ("index-state(" ++ unRepoName rname ++ ") = " ++ prettyShow (isiHeadTime isi))
return ()
IndexStateTime ts0 ->
-- isiMaxTime is the latest timestamp in the filtered view returned by
-- `readRepoIndex` above. It is always true that isiMaxTime is less or
-- equal to a requested IndexStateTime. When `isiMaxTime isi /= ts0` (or
-- equivalently `isiMaxTime isi < ts0`) it means that ts0 falls between
-- two timestamps in the index.
when (isiMaxTime isi /= ts0) $
let commonMsg =
"There is no index-state for '"
++ unRepoName rname
++ "' exactly at the requested timestamp ("
++ prettyShow ts0
++ "). "
in if isNothing $ timestampToUTCTime (isiMaxTime isi)
then
warn verbosity $
commonMsg
++ "Also, there are no index-states before the one requested, so the repository '"
++ unRepoName rname
++ "' will be empty."
else
info verbosity $
commonMsg
++ "Falling back to the previous index-state that exists: "
++ prettyShow (isiMaxTime isi)
pure
RepoData
{ rdRepoName = rname
, rdTimeStamp = isiMaxTime isi
, rdIndex = pis
, rdPreferences = deps
}
let activeRepos :: ActiveRepos
activeRepos = fromMaybe defaultActiveRepos mb_activeRepos
pkgss' <- case organizeByRepos activeRepos rdRepoName pkgss of
Right x -> return x
Left err -> warn verbosity err >> return (map (\x -> (x, CombineStrategyMerge)) pkgss)
let activeRepos' :: ActiveRepos
activeRepos' =
ActiveRepos
[ ActiveRepo (rdRepoName rd) strategy
| (rd, strategy) <- pkgss'
]
let totalIndexState :: TotalIndexState
totalIndexState =
makeTotalIndexState IndexStateHead $
Map.fromList
[ (n, IndexStateTime ts)
| (RepoData n ts _idx _prefs, _strategy) <- pkgss'
, -- e.g. file+noindex have nullTimestamp as their timestamp
ts /= NoTimestamp
]
let addIndex
:: PackageIndex UnresolvedSourcePackage
-> (RepoData, CombineStrategy)
-> PackageIndex UnresolvedSourcePackage
addIndex acc (RepoData _ _ _ _, CombineStrategySkip) = acc
addIndex acc (RepoData _ _ idx _, CombineStrategyMerge) = PackageIndex.merge acc idx
addIndex acc (RepoData _ _ idx _, CombineStrategyOverride) = PackageIndex.override acc idx
let pkgs :: PackageIndex UnresolvedSourcePackage
pkgs = foldl' addIndex mempty pkgss'
-- Note: preferences combined without using CombineStrategy
let prefs :: Map PackageName VersionRange
prefs =
Map.fromListWith
intersectVersionRanges
[ (name, range)
| (RepoData _n _ts _idx prefs', _strategy) <- pkgss'
, Dependency name range _ <- prefs'
]
_ <- evaluate pkgs
_ <- evaluate prefs
_ <- evaluate totalIndexState
return
( SourcePackageDb
{ packageIndex = pkgs
, packagePreferences = prefs
}
, totalIndexState
, activeRepos'
)
-- auxiliary data used in getSourcePackagesAtIndexState
data RepoData = RepoData
{ rdRepoName :: RepoName
, rdTimeStamp :: Timestamp
, rdIndex :: PackageIndex UnresolvedSourcePackage
, rdPreferences :: [Dependency]
}
-- | Read a repository index from disk, from the local file specified by
-- the 'Repo'.
--
-- All the 'SourcePackage's are marked as having come from the given 'Repo'.
--
-- This is a higher level wrapper used internally in cabal-install.
readRepoIndex
:: Verbosity
-> RepoContext
-> Repo
-> RepoIndexState
-> IO (PackageIndex UnresolvedSourcePackage, [Dependency], IndexStateInfo)
readRepoIndex verbosity repoCtxt repo idxState =
handleNotFound $ do
ret@(_, _, isi) <-
readPackageIndexCacheFile
verbosity
mkAvailablePackage
(RepoIndex repoCtxt repo)
idxState
when (isRepoRemote repo) $ do
warnIfIndexIsOld =<< getIndexFileAge repo
dieIfRequestedIdxIsNewer isi
pure ret
where
mkAvailablePackage pkgEntry =
SourcePackage
{ srcpkgPackageId = pkgid
, srcpkgDescription = pkgdesc
, srcpkgSource = case pkgEntry of
NormalPackage _ _ _ _ -> RepoTarballPackage repo pkgid Nothing
BuildTreeRef _ _ _ path _ -> LocalUnpackedPackage path
, srcpkgDescrOverride = case pkgEntry of
NormalPackage _ _ pkgtxt _ -> Just pkgtxt
_ -> Nothing
}
where
pkgdesc = packageDesc pkgEntry
pkgid = packageId pkgEntry
handleNotFound action = catchIO action $ \e ->
if isDoesNotExistError e
then do
case repo of
RepoRemote{..} -> warn verbosity $ exceptionMessageCabalInstall $ MissingPackageList repoRemote
RepoSecure{..} -> warn verbosity $ exceptionMessageCabalInstall $ MissingPackageList repoRemote
RepoLocalNoIndex local _ ->
warn verbosity $
"Error during construction of local+noindex "
++ unRepoName (localRepoName local)
++ " repository index: "
++ show e
return (mempty, mempty, emptyStateInfo)
else ioError e
isOldThreshold :: Double
isOldThreshold = 15 -- days
warnIfIndexIsOld dt = do
when (dt >= isOldThreshold) $ case repo of
RepoRemote{..} -> warn verbosity $ warnOutdatedPackageList repoRemote dt
RepoSecure{..} -> warn verbosity $ warnOutdatedPackageList repoRemote dt
RepoLocalNoIndex{} -> return ()
dieIfRequestedIdxIsNewer isi =
let latestTime = isiHeadTime isi
in case idxState of
IndexStateTime t -> when (t > latestTime) $ case repo of
RepoSecure{..} ->
dieWithException verbosity $ UnusableIndexState repoRemote latestTime t
RepoRemote{} -> pure ()
RepoLocalNoIndex{} -> return ()
IndexStateHead -> pure ()
warnOutdatedPackageList repoRemote dt =
"The package list for '"
++ unRepoName (remoteRepoName repoRemote)
++ "' is "
++ shows (floor dt :: Int) " days old.\nRun "
++ "'cabal update' to get the latest list of available packages."
-- | Return the age of the index file in days (as a Double).
getIndexFileAge :: Repo -> IO Double
getIndexFileAge repo = getFileAge $ indexBaseName repo <.> "tar"
-- | A set of files (or directories) that can be monitored to detect when
-- there might have been a change in the source packages.
getSourcePackagesMonitorFiles :: [Repo] -> [FilePath]
getSourcePackagesMonitorFiles repos =
concat
[ [ indexBaseName repo <.> "cache"
, indexBaseName repo <.> "timestamp"
]
| repo <- repos
]
-- | It is not necessary to call this, as the cache will be updated when the
-- index is read normally. However you can do the work earlier if you like.
updateRepoIndexCache :: Verbosity -> Index -> IO ()
updateRepoIndexCache verbosity index =
whenCacheOutOfDate index $ updatePackageIndexCacheFile verbosity index
whenCacheOutOfDate :: Index -> IO () -> IO ()
whenCacheOutOfDate index action = do
exists <- doesFileExist $ cacheFile index
if not exists
then action
else
if localNoIndex index
then return () -- TODO: don't update cache for local+noindex repositories
else do
indexTime <- getModTime $ indexFile index
cacheTime <- getModTime $ cacheFile index
when (indexTime > cacheTime) action
localNoIndex :: Index -> Bool
localNoIndex (RepoIndex _ (RepoLocalNoIndex{})) = True
localNoIndex _ = False
------------------------------------------------------------------------
-- Reading the index file
--
-- | An index entry is either a normal package, or a local build tree reference.
data PackageEntry
= NormalPackage PackageId GenericPackageDescription ByteString BlockNo
| BuildTreeRef
BuildTreeRefType
PackageId
GenericPackageDescription
FilePath
BlockNo
-- | A build tree reference is either a link or a snapshot.
data BuildTreeRefType = SnapshotRef | LinkRef
deriving (Eq, Show, Generic)
instance Binary BuildTreeRefType
instance Structured BuildTreeRefType
refTypeFromTypeCode :: Tar.TypeCode -> BuildTreeRefType
refTypeFromTypeCode t
| t == Tar.buildTreeRefTypeCode = LinkRef
| t == Tar.buildTreeSnapshotTypeCode = SnapshotRef
| otherwise =
error "Distribution.Client.IndexUtils.refTypeFromTypeCode: unknown type code"
typeCodeFromRefType :: BuildTreeRefType -> Tar.TypeCode
typeCodeFromRefType LinkRef = Tar.buildTreeRefTypeCode
typeCodeFromRefType SnapshotRef = Tar.buildTreeSnapshotTypeCode
instance Package PackageEntry where
packageId (NormalPackage pkgid _ _ _) = pkgid
packageId (BuildTreeRef _ pkgid _ _ _) = pkgid
packageDesc :: PackageEntry -> GenericPackageDescription
packageDesc (NormalPackage _ descr _ _) = descr
packageDesc (BuildTreeRef _ _ descr _ _) = descr
-- | Parse an uncompressed \"00-index.tar\" repository index file represented
-- as a 'ByteString'.
data PackageOrDep = Pkg PackageEntry | Dep Dependency
-- | Read @00-index.tar.gz@ and extract @.cabal@ and @preferred-versions@ files
--
-- We read the index using 'Tar.read', which gives us a lazily constructed
-- 'TarEntries'. We translate it to a list of entries using 'tarEntriesList',
-- which preserves the lazy nature of 'TarEntries', and finally 'concatMap' a
-- function over this to translate it to a list of IO actions returning
-- 'PackageOrDep's. We can use 'lazySequence' to turn this into a list of
-- 'PackageOrDep's, still maintaining the lazy nature of the original tar read.
parsePackageIndex :: Verbosity -> ByteString -> [IO (Maybe PackageOrDep)]
parsePackageIndex verbosity = concatMap (uncurry extract) . tarEntriesList . Tar.read
where
extract :: BlockNo -> Tar.Entry -> [IO (Maybe PackageOrDep)]
extract blockNo entry = tryExtractPkg ++ tryExtractPrefs
where
tryExtractPkg = do
mkPkgEntry <- maybeToList $ extractPkg verbosity entry blockNo
return $ fmap (fmap Pkg) mkPkgEntry
tryExtractPrefs = do
prefs' <- maybeToList $ extractPrefs entry
fmap (return . Just . Dep) prefs'
-- | Turn the 'Entries' data structure from the @tar@ package into a list,
-- and pair each entry with its block number.
--
-- NOTE: This preserves the lazy nature of 'Entries': the tar file is only read
-- as far as the list is evaluated.
tarEntriesList :: Show e => Tar.Entries e -> [(BlockNo, Tar.Entry)]
tarEntriesList = go 0
where
go !_ Tar.Done = []
go !_ (Tar.Fail e) = error ("tarEntriesList: " ++ show e)
go !n (Tar.Next e es') = (n, e) : go (Tar.nextEntryOffset e n) es'
extractPkg :: Verbosity -> Tar.Entry -> BlockNo -> Maybe (IO (Maybe PackageEntry))
extractPkg verbosity entry blockNo = case Tar.entryContent entry of
Tar.NormalFile content _
| takeExtension fileName == ".cabal" ->
case splitDirectories (normalise fileName) of
[pkgname, vers, _] -> case simpleParsec vers of
Just ver -> Just . return $ Just (NormalPackage pkgid descr content blockNo)
where
pkgid = PackageIdentifier (mkPackageName pkgname) ver
parsed = parseGenericPackageDescriptionMaybe (BS.toStrict content)
descr = case parsed of
Just d -> d
Nothing ->
error $
"Couldn't read cabal file "
++ show fileName
_ -> Nothing
_ -> Nothing
Tar.OtherEntryType typeCode content _
| Tar.isBuildTreeRefTypeCode typeCode ->
Just $ do
let path = byteStringToFilePath content
dirExists <- doesDirectoryExist path
if not dirExists
then return Nothing
else do
descr <- tryReadAddSourcePackageDesc verbosity path "Error reading package index."
return . Just $
BuildTreeRef
(refTypeFromTypeCode typeCode)
(packageId descr)
descr
path
blockNo
_ -> Nothing
where
fileName = Tar.entryPath entry
extractPrefs :: Tar.Entry -> Maybe [Dependency]
extractPrefs entry = case Tar.entryContent entry of
Tar.NormalFile content _
| isPreferredVersions entrypath ->
Just prefs
where
entrypath = Tar.entryPath entry
prefs = parsePreferredVersions content
_ -> Nothing
------------------------------------------------------------------------
-- Filename and parsers for 'preferred-versions' file.
--
-- | Expected name of the 'preferred-versions' file.
--
-- Contains special constraints, such as a preferred version of a package
-- or deprecations of certain package versions.
--
-- Expected format:
--
-- @
-- binary > 0.9.0.0 || < 0.9.0.0
-- text == 1.2.1.0
-- @
preferredVersions :: FilePath
preferredVersions = "preferred-versions"
-- | Does the given filename match with the expected name of 'preferred-versions'?
isPreferredVersions :: FilePath -> Bool
isPreferredVersions = (== preferredVersions) . takeFileName
-- | Parse `preferred-versions` file, ignoring any parse failures.
--
-- To obtain parse errors, use 'parsePreferredVersionsWarnings'.
parsePreferredVersions :: ByteString -> [Dependency]
parsePreferredVersions = rights . parsePreferredVersionsWarnings
-- | Parser error of the `preferred-versions` file.
data PreferredVersionsParseError = PreferredVersionsParseError
{ preferredVersionsParsecError :: String
-- ^ Parser error to show to a user.
, preferredVersionsOriginalDependency :: String
-- ^ Original input that produced the parser error.
}
deriving (Generic, Read, Show, Eq, Ord, Typeable)
-- | Parse `preferred-versions` file, collecting parse errors that can be shown
-- in error messages.
parsePreferredVersionsWarnings
:: ByteString
-> [Either PreferredVersionsParseError Dependency]
parsePreferredVersionsWarnings =
map parsePreference
. filter (not . isPrefixOf "--")
. lines
. fromUTF8LBS
where
parsePreference :: String -> Either PreferredVersionsParseError Dependency
parsePreference s = case eitherParsec s of
Left err ->
Left $
PreferredVersionsParseError
{ preferredVersionsParsecError = err
, preferredVersionsOriginalDependency = s
}
Right dep -> Right dep
------------------------------------------------------------------------
-- Reading and updating the index cache
--
-- | Variation on 'sequence' which evaluates the actions lazily
--
-- Pattern matching on the result list will execute just the first action;
-- more generally pattern matching on the first @n@ '(:)' nodes will execute
-- the first @n@ actions.
lazySequence :: [IO a] -> IO [a]
lazySequence = unsafeInterleaveIO . go
where
go [] = return []
go (x : xs) = do
x' <- x
xs' <- lazySequence xs
return (x' : xs')
-- | A lazy unfolder for lookup operations which return the current
-- value and (possibly) the next key
lazyUnfold :: (k -> IO (v, Maybe k)) -> k -> IO [(k, v)]
lazyUnfold step = goLazy . Just
where
goLazy s = unsafeInterleaveIO (go s)
go Nothing = return []
go (Just k) = do
(v, mk') <- step k
vs' <- goLazy mk'
return ((k, v) : vs')
-- | Which index do we mean?
data Index
= -- | The main index for the specified repository
RepoIndex RepoContext Repo
indexFile :: Index -> FilePath
indexFile (RepoIndex _ctxt repo) = indexBaseName repo <.> "tar"
cacheFile :: Index -> FilePath
cacheFile (RepoIndex _ctxt repo) = indexBaseName repo <.> "cache"
timestampFile :: Index -> FilePath
timestampFile (RepoIndex _ctxt repo) = indexBaseName repo <.> "timestamp"
-- | Return 'True' if 'Index' uses 01-index format (aka secure repo)
is01Index :: Index -> Bool
is01Index (RepoIndex _ repo) = case repo of
RepoSecure{} -> True
RepoRemote{} -> False
RepoLocalNoIndex{} -> True
updatePackageIndexCacheFile :: Verbosity -> Index -> IO ()
updatePackageIndexCacheFile verbosity index = do
info verbosity ("Updating index cache file " ++ cacheFile index ++ " ...")
withIndexEntries verbosity index callback callbackNoIndex
where
callback entries = do
let !maxTs = maximumTimestamp (map cacheEntryTimestamp entries)
cache =
Cache
{ cacheHeadTs = maxTs
, cacheEntries = entries
}
writeIndexCache index cache
info
verbosity
( "Index cache updated to index-state "
++ prettyShow (cacheHeadTs cache)
)
callbackNoIndex entries = do
writeNoIndexCache verbosity index $ NoIndexCache entries
info verbosity "Index cache updated"
-- | Read the index (for the purpose of building a cache)
--
-- The callback is provided with list of cache entries, which is guaranteed to
-- be lazily constructed. This list must ONLY be used in the scope of the
-- callback; when the callback is terminated the file handle to the index will
-- be closed and further attempts to read from the list will result in (pure)
-- I/O exceptions.
--
-- In the construction of the index for a secure repo we take advantage of the
-- index built by the @hackage-security@ library to avoid reading the @.tar@
-- file as much as possible (we need to read it only to extract preferred
-- versions). This helps performance, but is also required for correctness:
-- the new @01-index.tar.gz@ may have multiple versions of preferred-versions
-- files, and 'parsePackageIndex' does not correctly deal with that (see #2956);
-- by reading the already-built cache from the security library we will be sure
-- to only read the latest versions of all files.
--
-- TODO: It would be nicer if we actually incrementally updated @cabal@'s
-- cache, rather than reconstruct it from zero on each update. However, this
-- would require a change in the cache format.
withIndexEntries
:: Verbosity
-> Index
-> ([IndexCacheEntry] -> IO a)
-> ([NoIndexCacheEntry] -> IO a)
-> IO a
withIndexEntries _ (RepoIndex repoCtxt repo@RepoSecure{}) callback _ =
repoContextWithSecureRepo repoCtxt repo $ \repoSecure ->
Sec.withIndex repoSecure $ \Sec.IndexCallbacks{..} -> do
-- Incrementally (lazily) read all the entries in the tar file in order,
-- including all revisions, not just the last revision of each file
indexEntries <- lazyUnfold indexLookupEntry (Sec.directoryFirst indexDirectory)
callback
[ cacheEntry
| (dirEntry, indexEntry) <- indexEntries
, cacheEntry <- toCacheEntries dirEntry indexEntry
]
where
toCacheEntries
:: Sec.DirectoryEntry
-> Sec.Some Sec.IndexEntry
-> [IndexCacheEntry]
toCacheEntries dirEntry (Sec.Some sie) =
case Sec.indexEntryPathParsed sie of
Nothing -> [] -- skip unrecognized file
Just (Sec.IndexPkgMetadata _pkgId) -> [] -- skip metadata
Just (Sec.IndexPkgCabal pkgId) ->
force
[CachePackageId pkgId blockNo timestamp]
Just (Sec.IndexPkgPrefs _pkgName) ->
force
[ CachePreference dep blockNo timestamp
| dep <- parsePreferredVersions (Sec.indexEntryContent sie)
]
where
blockNo = Sec.directoryEntryBlockNo dirEntry
timestamp =
epochTimeToTimestamp $
Sec.indexEntryTime sie
withIndexEntries verbosity (RepoIndex _repoCtxt (RepoLocalNoIndex (LocalRepo name localDir _) _cacheDir)) _ callback = do
dirContents <- listDirectory localDir
let contentSet = Set.fromList dirContents
entries <- handle handler $ fmap catMaybes $ for dirContents $ \file -> do
case isTarGz file of
Nothing
| isPreferredVersions file -> do
contents <- BS.readFile (localDir </> file)
let versionPreferencesParsed = parsePreferredVersionsWarnings contents
let (warnings, versionPreferences) = partitionEithers versionPreferencesParsed
unless (null warnings) $ do
warn verbosity $
"withIndexEntries: failed to parse some entries of \"preferred-versions\" found at: "
++ (localDir </> file)
for_ warnings $ \err -> do
warn verbosity $ "* \"" ++ preferredVersionsOriginalDependency err
warn verbosity $ "Parser Error: " ++ preferredVersionsParsecError err
return $ Just $ NoIndexCachePreference versionPreferences
| otherwise -> do
unless (takeFileName file == "noindex.cache" || ".cabal" `isSuffixOf` file) $
info verbosity $
"Skipping " ++ file
return Nothing
Just pkgid | cabalPath `Set.member` contentSet -> do
contents <- BSS.readFile (localDir </> cabalPath)
for (parseGenericPackageDescriptionMaybe contents) $ \gpd ->
return (CacheGPD gpd contents)
where
cabalPath = prettyShow pkgid ++ ".cabal"
Just pkgId -> do
-- check for the right named .cabal file in the compressed tarball
tarGz <- BS.readFile (localDir </> file)
let tar = GZip.decompress tarGz
entries = Tar.read tar
case Tar.foldEntries (readCabalEntry pkgId) Nothing (const Nothing) entries of
Just ce -> return (Just ce)
Nothing -> dieWithException verbosity $ CannotReadCabalFile file
let (prefs, gpds) =
partitionEithers $
map
( \case
NoIndexCachePreference deps -> Left deps
CacheGPD gpd _ -> Right gpd
)
entries
info verbosity $ "Entries in file+noindex repository " ++ unRepoName name
for_ gpds $ \gpd ->
info verbosity $ "- " ++ prettyShow (package $ Distribution.PackageDescription.packageDescription gpd)
unless (null prefs) $ do
info verbosity $ "Preferred versions in file+noindex repository " ++ unRepoName name
for_ (concat prefs) $ \pref ->
info verbosity ("* " ++ prettyShow pref)
callback entries
where
handler :: IOException -> IO a
handler e = dieWithException verbosity $ ErrorUpdatingIndex (unRepoName name) e
isTarGz :: FilePath -> Maybe PackageIdentifier
isTarGz fp = do
pfx <- stripSuffix ".tar.gz" fp
simpleParsec pfx
stripSuffix sfx str = fmap reverse (stripPrefix (reverse sfx) (reverse str))
-- look for <pkgid>/<pkgname>.cabal inside the tarball
readCabalEntry :: PackageIdentifier -> Tar.Entry -> Maybe NoIndexCacheEntry -> Maybe NoIndexCacheEntry
readCabalEntry pkgId entry Nothing
| filename == Tar.entryPath entry
, Tar.NormalFile contents _ <- Tar.entryContent entry =
let bs = BS.toStrict contents
in ((`CacheGPD` bs) <$> parseGenericPackageDescriptionMaybe bs)
where
filename = prettyShow pkgId FilePath.</> prettyShow (packageName pkgId) ++ ".cabal"
readCabalEntry _ _ x = x
withIndexEntries verbosity index callback _ = do
-- non-secure repositories
withFile (indexFile index) ReadMode $ \h -> do
bs <- maybeDecompress `fmap` BS.hGetContents h
pkgsOrPrefs <- lazySequence $ parsePackageIndex verbosity bs
callback $ map toCache (catMaybes pkgsOrPrefs)
where
toCache :: PackageOrDep -> IndexCacheEntry
toCache (Pkg (NormalPackage pkgid _ _ blockNo)) = CachePackageId pkgid blockNo NoTimestamp
toCache (Pkg (BuildTreeRef refType _ _ _ blockNo)) = CacheBuildTreeRef refType blockNo
toCache (Dep d) = CachePreference d 0 NoTimestamp
-- | Read package data from a repository.
-- Throws IOException if any arise while accessing the index
-- (unless the repo is local+no-index) and dies if the cache
-- is corrupted and cannot be regenerated correctly.
readPackageIndexCacheFile
:: Package pkg
=> Verbosity
-> (PackageEntry -> pkg)
-> Index
-> RepoIndexState
-> IO (PackageIndex pkg, [Dependency], IndexStateInfo)
readPackageIndexCacheFile verbosity mkPkg index idxState
| localNoIndex index = do
cache0 <- readNoIndexCache verbosity index
(pkgs, prefs) <- packageNoIndexFromCache verbosity mkPkg cache0
pure (pkgs, prefs, emptyStateInfo)
| otherwise = do
(cache, isi) <- getIndexCache verbosity index idxState
indexHnd <- openFile (indexFile index) ReadMode
(pkgs, deps) <- packageIndexFromCache verbosity mkPkg indexHnd cache
pure (pkgs, deps, isi)
-- | Read 'Cache' and 'IndexStateInfo' from the repository index file.
-- Throws IOException if any arise (e.g. the index or its cache are missing).
-- Dies if the index cache is corrupted and cannot be regenerated correctly.
getIndexCache :: Verbosity -> Index -> RepoIndexState -> IO (Cache, IndexStateInfo)
getIndexCache verbosity index idxState =
filterCache idxState <$> readIndexCache verbosity index
packageIndexFromCache
:: Package pkg
=> Verbosity
-> (PackageEntry -> pkg)
-> Handle
-> Cache
-> IO (PackageIndex pkg, [Dependency])
packageIndexFromCache verbosity mkPkg hnd cache = do
(pkgs, prefs) <- packageListFromCache verbosity mkPkg hnd cache
pkgIndex <- evaluate $ PackageIndex.fromList pkgs
return (pkgIndex, prefs)
packageNoIndexFromCache
:: forall pkg
. Package pkg
=> Verbosity
-> (PackageEntry -> pkg)
-> NoIndexCache
-> IO (PackageIndex pkg, [Dependency])
packageNoIndexFromCache _verbosity mkPkg cache = do
let (pkgs, prefs) = packageListFromNoIndexCache
pkgIndex <- evaluate $ PackageIndex.fromList pkgs
pure (pkgIndex, prefs)
where
packageListFromNoIndexCache :: ([pkg], [Dependency])
packageListFromNoIndexCache = foldr go mempty (noIndexCacheEntries cache)
go :: NoIndexCacheEntry -> ([pkg], [Dependency]) -> ([pkg], [Dependency])
go (CacheGPD gpd bs) (pkgs, prefs) =
let pkgId = package $ Distribution.PackageDescription.packageDescription gpd
in (mkPkg (NormalPackage pkgId gpd (BS.fromStrict bs) 0) : pkgs, prefs)
go (NoIndexCachePreference deps) (pkgs, prefs) =
(pkgs, deps ++ prefs)
-- | Read package list
--
-- The result package releases and preference entries are guaranteed
-- to be unique.
--
-- Note: 01-index.tar is an append-only index and therefore contains
-- all .cabal edits and preference-updates. The masking happens
-- here, i.e. the semantics that later entries in a tar file mask
-- earlier ones is resolved in this function.
packageListFromCache
:: Verbosity
-> (PackageEntry -> pkg)
-> Handle
-> Cache
-> IO ([pkg], [Dependency])
packageListFromCache verbosity mkPkg hnd Cache{..} = accum mempty [] mempty cacheEntries
where
accum !srcpkgs btrs !prefs [] = return (Map.elems srcpkgs ++ btrs, Map.elems prefs)
accum srcpkgs btrs prefs (CachePackageId pkgid blockno _ : entries) = do
-- Given the cache entry, make a package index entry.
-- The magic here is that we use lazy IO to read the .cabal file
-- from the index tarball if it turns out that we need it.
-- Most of the time we only need the package id.
~(pkg, pkgtxt) <- unsafeInterleaveIO $ do
pkgtxt <- getEntryContent blockno
pkg <- readPackageDescription pkgid pkgtxt
return (pkg, pkgtxt)
let srcpkg = mkPkg (NormalPackage pkgid pkg pkgtxt blockno)
accum (Map.insert pkgid srcpkg srcpkgs) btrs prefs entries
accum srcpkgs btrs prefs (CacheBuildTreeRef refType blockno : entries) = do
-- We have to read the .cabal file eagerly here because we can't cache the
-- package id for build tree references - the user might edit the .cabal
-- file after the reference was added to the index.
path <- fmap byteStringToFilePath . getEntryContent $ blockno
pkg <- do
let err = "Error reading package index from cache."
tryReadAddSourcePackageDesc verbosity path err
let srcpkg = mkPkg (BuildTreeRef refType (packageId pkg) pkg path blockno)
accum srcpkgs (srcpkg : btrs) prefs entries
accum srcpkgs btrs prefs (CachePreference pref@(Dependency pn _ _) _ _ : entries) =
accum srcpkgs btrs (Map.insert pn pref prefs) entries
getEntryContent :: BlockNo -> IO ByteString
getEntryContent blockno = do
entry <- Tar.hReadEntry hnd blockno
case Tar.entryContent entry of
Tar.NormalFile content _size -> return content
Tar.OtherEntryType typecode content _size
| Tar.isBuildTreeRefTypeCode typecode ->
return content
_ -> interror "unexpected tar entry type"
readPackageDescription :: PackageIdentifier -> ByteString -> IO GenericPackageDescription
readPackageDescription pkgid content =
case snd $ PackageDesc.Parse.runParseResult $ parseGenericPackageDescription $ BS.toStrict content of
Right gpd -> return gpd
Left (Just specVer, _) | specVer >= mkVersion [2, 2] -> return (dummyPackageDescription specVer)
Left _ -> interror "failed to parse .cabal file"
where
dummyPackageDescription :: Version -> GenericPackageDescription
dummyPackageDescription specVer =
GenericPackageDescription
{ packageDescription =
emptyPackageDescription
{ package = pkgid
, synopsis = dummySynopsis
}
, gpdScannedVersion = Just specVer -- tells index scanner to skip this file.
, genPackageFlags = []
, condLibrary = Nothing
, condSubLibraries = []
, condForeignLibs = []
, condExecutables = []
, condTestSuites = []
, condBenchmarks = []
}
dummySynopsis = "<could not be parsed due to unsupported CABAL spec-version>"
interror :: String -> IO a
interror msg =
dieWithException verbosity $ InternalError msg
------------------------------------------------------------------------
-- Index cache data structure --
-- | Read a repository cache from the filesystem
--
-- If a corrupted index cache is detected this function regenerates
-- the index cache and then reattempt to read the index once (and
-- 'dieWithException's if it fails again).
readIndexCache :: Verbosity -> Index -> IO Cache
readIndexCache verbosity index = do
cacheOrFail <- readIndexCache' index
case cacheOrFail of
Left msg -> do
warn verbosity $
concat
[ "Parsing the index cache failed ("
, msg
, "). "
, "Trying to regenerate the index cache..."
]
updatePackageIndexCacheFile verbosity index
either (dieWithException verbosity . CorruptedIndexCache) (return . hashConsCache) =<< readIndexCache' index
Right res -> return (hashConsCache res)
-- | Read a no-index repository cache from the filesystem
--
-- If a corrupted index cache is detected this function regenerates
-- the index cache and then reattempts to read the index once (and
-- 'dieWithException's if it fails again). Throws IOException if any arise.
readNoIndexCache :: Verbosity -> Index -> IO NoIndexCache
readNoIndexCache verbosity index = do
cacheOrFail <- readNoIndexCache' index
case cacheOrFail of
Left msg -> do
warn verbosity $
concat
[ "Parsing the index cache failed ("
, msg
, "). "
, "Trying to regenerate the index cache..."
]
updatePackageIndexCacheFile verbosity index
either (dieWithException verbosity . CorruptedIndexCache) return =<< readNoIndexCache' index
-- we don't hash cons local repository cache, they are hopefully small
Right res -> return res
-- | Read the 'Index' cache from the filesystem. Throws IO exceptions
-- if any arise and returns Left on invalid input.
readIndexCache' :: Index -> IO (Either String Cache)
readIndexCache' index
| is01Index index =
structuredDecodeFileOrFail (cacheFile index)
| otherwise =
Right . read00IndexCache <$> BSS.readFile (cacheFile index)
readNoIndexCache' :: Index -> IO (Either String NoIndexCache)
readNoIndexCache' index = structuredDecodeFileOrFail (cacheFile index)
-- | Write the 'Index' cache to the filesystem
writeIndexCache :: Index -> Cache -> IO ()
writeIndexCache index cache
| is01Index index = structuredEncodeFile (cacheFile index) cache
| otherwise = writeFile (cacheFile index) (show00IndexCache cache)
writeNoIndexCache :: Verbosity -> Index -> NoIndexCache -> IO ()
writeNoIndexCache verbosity index cache = do
let path = cacheFile index
createDirectoryIfMissingVerbose verbosity True (takeDirectory path)
structuredEncodeFile path cache
-- | Write the 'IndexState' to the filesystem
writeIndexTimestamp :: Index -> RepoIndexState -> IO ()
writeIndexTimestamp index st =
writeFile (timestampFile index) (prettyShow st)
-- | Read out the "current" index timestamp, i.e., what
-- timestamp you would use to revert to this version.
--
-- Note: this is not the same as 'readIndexTimestamp'!
-- This resolves HEAD to the index's 'isiHeadTime', i.e.
-- the index latest known timestamp.
--
-- Return NoTimestamp if the index has never been updated.
currentIndexTimestamp :: Verbosity -> Index -> IO Timestamp
currentIndexTimestamp verbosity index = do
mb_is <- readIndexTimestamp verbosity index
case mb_is of
-- If the index timestamp file specifies an index state time, use that
Just (IndexStateTime ts) ->
return ts
-- Otherwise used the head time as stored in the index cache
_otherwise ->
fmap (isiHeadTime . snd) (getIndexCache verbosity index IndexStateHead)
`catchIO` \e ->
if isDoesNotExistError e
then return NoTimestamp
else ioError e
-- | Read the 'IndexState' from the filesystem
readIndexTimestamp :: Verbosity -> Index -> IO (Maybe RepoIndexState)
readIndexTimestamp verbosity index =
fmap simpleParsec (readFile (timestampFile index))
`catchIO` \e ->
if isDoesNotExistError e
then return Nothing
else do
warn verbosity $ "Warning: could not read current index timestamp: " ++ displayException e
return Nothing
-- | Optimise sharing of equal values inside 'Cache'
--
-- c.f. https://en.wikipedia.org/wiki/Hash_consing
hashConsCache :: Cache -> Cache
hashConsCache cache0 =
cache0{cacheEntries = go mempty mempty (cacheEntries cache0)}
where
-- TODO/NOTE:
--
-- If/when we redo the binary serialisation via e.g. CBOR and we
-- are able to use incremental decoding, we may want to move the
-- hash-consing into the incremental deserialisation, or
-- alternatively even do something like
-- http://cbor.schmorp.de/value-sharing
--
go _ _ [] = []
-- for now we only optimise only CachePackageIds since those
-- represent the vast majority
go !pns !pvs (CachePackageId pid bno ts : rest) =
CachePackageId pid' bno ts : go pns' pvs' rest
where
!pid' = PackageIdentifier pn' pv'
(!pn', !pns') = mapIntern pn pns
(!pv', !pvs') = mapIntern pv pvs
PackageIdentifier pn pv = pid
go pns pvs (x : xs) = x : go pns pvs xs
mapIntern :: Ord k => k -> Map.Map k k -> (k, Map.Map k k)
mapIntern k m = maybe (k, Map.insert k k m) (\k' -> (k', m)) (Map.lookup k m)
-- | Cabal caches various information about the Hackage index
data Cache = Cache
{ cacheHeadTs :: Timestamp
-- ^ maximum/latest 'Timestamp' among 'cacheEntries'; unless the
-- invariant of 'cacheEntries' being in chronological order is
-- violated, this corresponds to the last (seen) 'Timestamp' in
-- 'cacheEntries'
, cacheEntries :: [IndexCacheEntry]
}
deriving (Show, Generic)
instance NFData Cache where
rnf = rnf . cacheEntries
-- | Cache format for 'file+noindex' repositories
newtype NoIndexCache = NoIndexCache
{ noIndexCacheEntries :: [NoIndexCacheEntry]
}
deriving (Show, Generic)
instance NFData NoIndexCache where
rnf = rnf . noIndexCacheEntries
-- | Tar files are block structured with 512 byte blocks. Every header and file
-- content starts on a block boundary.
type BlockNo = Word32 -- Tar.TarEntryOffset
data IndexCacheEntry
= CachePackageId PackageId !BlockNo !Timestamp
| CachePreference Dependency !BlockNo !Timestamp
| CacheBuildTreeRef !BuildTreeRefType !BlockNo
-- NB: CacheBuildTreeRef is irrelevant for 01-index & v2-build
deriving (Eq, Show, Generic)
data NoIndexCacheEntry
= CacheGPD GenericPackageDescription !BSS.ByteString
| NoIndexCachePreference [Dependency]
deriving (Eq, Show, Generic)
instance NFData IndexCacheEntry where
rnf (CachePackageId pkgid _ _) = rnf pkgid
rnf (CachePreference dep _ _) = rnf dep
rnf (CacheBuildTreeRef _ _) = ()
instance NFData NoIndexCacheEntry where
rnf (CacheGPD gpd bs) = rnf gpd `seq` rnf bs
rnf (NoIndexCachePreference dep) = rnf dep
cacheEntryTimestamp :: IndexCacheEntry -> Timestamp
cacheEntryTimestamp (CacheBuildTreeRef _ _) = NoTimestamp
cacheEntryTimestamp (CachePreference _ _ ts) = ts
cacheEntryTimestamp (CachePackageId _ _ ts) = ts
----------------------------------------------------------------------------
-- new binary 01-index.cache format
instance Binary Cache
instance Binary IndexCacheEntry
instance Binary NoIndexCache
instance Structured Cache
instance Structured IndexCacheEntry
instance Structured NoIndexCache
-- | We need to save only .cabal file contents
instance Binary NoIndexCacheEntry where
put (CacheGPD _ bs) = do
put (0 :: Word8)
put bs
put (NoIndexCachePreference dep) = do
put (1 :: Word8)
put dep
get = do
t :: Word8 <- get
case t of
0 -> do
bs <- get
case parseGenericPackageDescriptionMaybe bs of
Just gpd -> return (CacheGPD gpd bs)
Nothing -> fail "Failed to parse GPD"
1 -> do
NoIndexCachePreference <$> get
_ -> fail "Failed to parse NoIndexCacheEntry"
instance Structured NoIndexCacheEntry where
structure = nominalStructure
----------------------------------------------------------------------------
-- legacy 00-index.cache format
packageKey, blocknoKey, buildTreeRefKey, preferredVersionKey :: String
packageKey = "pkg:"
blocknoKey = "b#"
buildTreeRefKey = "build-tree-ref:"
preferredVersionKey = "pref-ver:"
-- legacy 00-index.cache format
read00IndexCache :: BSS.ByteString -> Cache
read00IndexCache bs =
Cache
{ cacheHeadTs = NoTimestamp
, cacheEntries = mapMaybe read00IndexCacheEntry $ BSS.lines bs
}
read00IndexCacheEntry :: BSS.ByteString -> Maybe IndexCacheEntry
read00IndexCacheEntry = \line ->
case BSS.words line of
[key, pkgnamestr, pkgverstr, sep, blocknostr]
| key == BSS.pack packageKey && sep == BSS.pack blocknoKey ->
case ( parseName pkgnamestr
, parseVer pkgverstr []
, parseBlockNo blocknostr
) of
(Just pkgname, Just pkgver, Just blockno) ->
Just
( CachePackageId
(PackageIdentifier pkgname pkgver)
blockno
NoTimestamp
)
_ -> Nothing
[key, typecodestr, blocknostr] | key == BSS.pack buildTreeRefKey ->
case (parseRefType typecodestr, parseBlockNo blocknostr) of
(Just refType, Just blockno) ->
Just (CacheBuildTreeRef refType blockno)
_ -> Nothing
(key : remainder) | key == BSS.pack preferredVersionKey -> do
pref <- simpleParsecBS (BSS.unwords remainder)
return $ CachePreference pref 0 NoTimestamp
_ -> Nothing
where
parseName str
| BSS.all (\c -> isAlphaNum c || c == '-') str =
Just (mkPackageName (BSS.unpack str))
| otherwise = Nothing
parseVer str vs =
case BSS.readInt str of
Nothing -> Nothing
Just (v, str') -> case BSS.uncons str' of
Just ('.', str'') -> parseVer str'' (v : vs)
Just _ -> Nothing
Nothing -> Just (mkVersion (reverse (v : vs)))
parseBlockNo str =
case BSS.readInt str of
Just (blockno, remainder)
| BSS.null remainder -> Just (fromIntegral blockno)
_ -> Nothing
parseRefType str =
case BSS.uncons str of
Just (typeCode, remainder)
| BSS.null remainder && Tar.isBuildTreeRefTypeCode typeCode ->
Just (refTypeFromTypeCode typeCode)
_ -> Nothing
-- legacy 00-index.cache format
show00IndexCache :: Cache -> String
show00IndexCache Cache{..} = unlines $ map show00IndexCacheEntry cacheEntries
show00IndexCacheEntry :: IndexCacheEntry -> String
show00IndexCacheEntry entry = unwords $ case entry of
CachePackageId pkgid b _ ->
[ packageKey
, prettyShow (packageName pkgid)
, prettyShow (packageVersion pkgid)
, blocknoKey
, show b
]
CacheBuildTreeRef tr b ->
[ buildTreeRefKey
, [typeCodeFromRefType tr]
, show b
]
CachePreference dep _ _ ->
[ preferredVersionKey
, prettyShow dep
]