diff options
Diffstat (limited to 'driver')
| -rw-r--r-- | driver/Main.hs | 23 | ||||
| -rw-r--r-- | driver/ResponseFile.hs | 110 |
2 files changed, 111 insertions, 22 deletions
diff --git a/driver/Main.hs b/driver/Main.hs index ccbb8b7d..852f44c7 100644 --- a/driver/Main.hs +++ b/driver/Main.hs @@ -1,29 +1,8 @@ -{-# LANGUAGE ScopedTypeVariables #-} module Main where -import Control.Exception import Documentation.Haddock (haddock) +import ResponseFile (expandResponse) import System.Environment (getArgs) -import System.Exit (exitFailure) -import System.IO main :: IO () main = getArgs >>= expandResponse >>= haddock - - --- | Arguments which look like '@foo' will be replaced with the --- contents of file @foo@. The contents will be passed through 'words' --- and blanks filtered out first. --- --- We quit if the file is not found or reading somehow fails. -expandResponse :: [String] -> IO [String] -expandResponse = fmap concat . mapM expand - where - expand :: String -> IO [String] - expand ('@':f) = readFileExc f >>= return . filter (not . null) . lines - expand x = return [x] - - readFileExc f = - readFile f `catch` \(e :: IOException) -> do - hPutStrLn stderr $ "Error while expanding response file: " ++ show e - exitFailure diff --git a/driver/ResponseFile.hs b/driver/ResponseFile.hs new file mode 100644 index 00000000..253c6004 --- /dev/null +++ b/driver/ResponseFile.hs @@ -0,0 +1,110 @@ +{-# LANGUAGE ScopedTypeVariables #-} +module ResponseFile ( + unescapeArgs, + escapeArgs, + expandResponse + ) where + +import Control.Exception +import Data.Char (isSpace) +import Data.Foldable (foldl') +import System.Exit (exitFailure) +import System.IO + + +-- | Given a string of concatenated strings, separate each by removing +-- a layer of /quoting/ and\/or /escaping/ of certain characters. +-- +-- These characters are: any whitespace, single quote, double quote, +-- and the backslash character. The backslash character always +-- escapes (i.e., passes through without further consideration) the +-- character which follows. Characters can also be escaped in blocks +-- by quoting (i.e., surrounding the blocks with matching pairs of +-- either single- or double-quotes which are not themselves escaped). +-- +-- Any whitespace which appears outside of either of the quoting and +-- escaping mechanisms, is interpreted as having been added by this +-- special concatenation process to designate where the boundaries +-- are between the original, un-concatenated list of strings. These +-- added whitespace characters are removed from the output. +-- +-- > unescapeArgs "hello\\ \\\"world\\\"\n" == escapeArgs "hello \"world\"" +unescapeArgs :: String -> [String] +unescapeArgs = filter (not . null) . unescape + +-- | Given a list of strings, concatenate them into a single string +-- with escaping of certain characters, and the addition of a newline +-- between each string. The escaping is done by adding a single +-- backslash character before any whitespace, single quote, double +-- quote, or backslash character, so this escaping character must be +-- removed. Unescaped whitespace (in this case, newline) is part +-- of this "transport" format to indicate the end of the previous +-- string and the start of a new string. +-- +-- While 'unescapeArgs' allows using quoting (i.e., convenient +-- escaping of many characters) by having matching sets of single- or +-- double-quotes,'escapeArgs' does not use the quoting mechasnism, +-- and thus will always escape any whitespace, quotes, and +-- backslashes. +-- +-- > unescapeArgs "hello\\ \\\"world\\\"\\n" == escapeArgs "hello \"world\"" +escapeArgs :: [String] -> String +escapeArgs = unlines . map escapeArg + +-- | Arguments which look like '@foo' will be replaced with the +-- contents of file @foo@. A gcc-like syntax for response files arguments +-- is expected. This must re-constitute the argument list by doing an +-- inverse of the escaping mechanism done by the calling-program side. +-- +-- We quit if the file is not found or reading somehow fails. +-- (A convenience routine for haddock or possibly other clients) +expandResponse :: [String] -> IO [String] +expandResponse = fmap concat . mapM expand + where + expand :: String -> IO [String] + expand ('@':f) = readFileExc f >>= return . unescapeArgs + expand x = return [x] + + readFileExc f = + readFile f `catch` \(e :: IOException) -> do + hPutStrLn stderr $ "Error while expanding response file: " ++ show e + exitFailure + +data Quoting = NoneQ | SngQ | DblQ + +unescape :: String -> [String] +unescape args = reverse . map reverse $ go args NoneQ False [] [] + where + -- n.b., the order of these cases matters; these are cribbed from gcc + -- case 1: end of input + go [] _q _bs a as = a:as + -- case 2: back-slash escape in progress + go (c:cs) q True a as = go cs q False (c:a) as + -- case 3: no back-slash escape in progress, but got a back-slash + go (c:cs) q False a as + | '\\' == c = go cs q True a as + -- case 4: single-quote escaping in progress + go (c:cs) SngQ False a as + | '\'' == c = go cs NoneQ False a as + | otherwise = go cs SngQ False (c:a) as + -- case 5: double-quote escaping in progress + go (c:cs) DblQ False a as + | '"' == c = go cs NoneQ False a as + | otherwise = go cs DblQ False (c:a) as + -- case 6: no escaping is in progress + go (c:cs) NoneQ False a as + | isSpace c = go cs NoneQ False [] (a:as) + | '\'' == c = go cs SngQ False a as + | '"' == c = go cs DblQ False a as + | otherwise = go cs NoneQ False (c:a) as + +escapeArg :: String -> String +escapeArg = reverse . foldl' escape [] + +escape :: String -> Char -> String +escape cs c + | isSpace c + || '\\' == c + || '\'' == c + || '"' == c = c:'\\':cs -- n.b., our caller must reverse the result + | otherwise = c:cs |