git-annex/Annex/View/ViewedFile.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

86 lines
2.4 KiB
Haskell

{- filenames (not paths) used in views
-
- Copyright 2014 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE CPP #-}
module Annex.View.ViewedFile (
ViewedFile,
MkViewedFile,
viewedFileFromReference,
viewedFileReuse,
dirFromViewedFile,
prop_viewedFile_roundtrips,
) where
import Annex.Common
type FileName = String
type ViewedFile = FileName
type MkViewedFile = FilePath -> ViewedFile
{- Converts a filepath used in a reference branch to the
- filename that will be used in the view.
-
- No two filepaths from the same branch should yeild the same result,
- so all directory structure needs to be included in the output filename
- in some way.
-
- So, from dir/subdir/file.foo, generate file_%dir%subdir%.foo
-}
viewedFileFromReference :: MkViewedFile
viewedFileFromReference f = concat
[ escape base
, if null dirs then "" else "_%" ++ intercalate "%" (map escape dirs) ++ "%"
, escape $ concat extensions
]
where
(path, basefile) = splitFileName f
dirs = filter (/= ".") $ map dropTrailingPathSeparator (splitPath path)
(base, extensions) = splitShortExtensions basefile
{- To avoid collisions with filenames or directories that contain
- '%', and to allow the original directories to be extracted
- from the ViewedFile, '%' is escaped. )
-}
escape :: String -> String
escape = replace "%" (escchar:'%':[]) . replace [escchar] [escchar, escchar]
escchar :: Char
#ifndef mingw32_HOST_OS
escchar = '\\'
#else
-- \ is path separator on Windows, so instead use !
escchar = '!'
#endif
{- For use when operating already within a view, so whatever filepath
- is present in the work tree is already a ViewedFile. -}
viewedFileReuse :: MkViewedFile
viewedFileReuse = takeFileName
{- Extracts from a ViewedFile the directory where the file is located on
- in the reference branch. -}
dirFromViewedFile :: ViewedFile -> FilePath
dirFromViewedFile = joinPath . drop 1 . sep [] ""
where
sep l _ [] = reverse l
sep l curr (c:cs)
| c == '%' = sep (reverse curr:l) "" cs
| c == escchar = case cs of
(c':cs') -> sep l (c':curr) cs'
[] -> sep l curr cs
| otherwise = sep l (c:curr) cs
prop_viewedFile_roundtrips :: FilePath -> Bool
prop_viewedFile_roundtrips f
-- Relative filenames wanted, not directories.
| any (isPathSeparator) (end f ++ beginning f) = True
| isAbsolute f = True
| otherwise = dir == dirFromViewedFile (viewedFileFromReference f)
where
dir = joinPath $ beginning $ splitDirectories f