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-rw-r--r--src/Utility/SafeCommand.hs64
1 files changed, 32 insertions, 32 deletions
diff --git a/src/Utility/SafeCommand.hs b/src/Utility/SafeCommand.hs
index 9eaa5308..9102b726 100644
--- a/src/Utility/SafeCommand.hs
+++ b/src/Utility/SafeCommand.hs
@@ -5,44 +5,45 @@
- License: BSD-2-clause
-}
+{-# OPTIONS_GHC -fno-warn-tabs #-}
+
module Utility.SafeCommand where
import System.Exit
import Utility.Process
import Data.String.Utils
-import Control.Applicative
import System.FilePath
import Data.Char
+import Control.Applicative
+import Prelude
-{- A type for parameters passed to a shell command. A command can
- - be passed either some Params (multiple parameters can be included,
- - whitespace-separated, or a single Param (for when parameters contain
- - whitespace), or a File.
- -}
-data CommandParam = Params String | Param String | File FilePath
+-- | Parameters that can be passed to a shell command.
+data CommandParam
+ = Param String -- ^ A parameter
+ | File FilePath -- ^ The name of a file
deriving (Eq, Show, Ord)
-{- Used to pass a list of CommandParams to a function that runs
- - a command and expects Strings. -}
+-- | Used to pass a list of CommandParams to a function that runs
+-- a command and expects Strings. -}
toCommand :: [CommandParam] -> [String]
-toCommand = concatMap unwrap
+toCommand = map unwrap
where
- unwrap (Param s) = [s]
- unwrap (Params s) = filter (not . null) (split " " s)
+ unwrap (Param s) = s
-- Files that start with a non-alphanumeric that is not a path
-- separator are modified to avoid the command interpreting them as
-- options or other special constructs.
unwrap (File s@(h:_))
- | isAlphaNum h || h `elem` pathseps = [s]
- | otherwise = ["./" ++ s]
- unwrap (File s) = [s]
+ | isAlphaNum h || h `elem` pathseps = s
+ | otherwise = "./" ++ s
+ unwrap (File s) = s
-- '/' is explicitly included because it's an alternative
-- path separator on Windows.
pathseps = pathSeparator:"./"
-{- Run a system command, and returns True or False
- - if it succeeded or failed.
- -}
+-- | Run a system command, and returns True or False if it succeeded or failed.
+--
+-- This and other command running functions in this module log the commands
+-- run at debug level, using System.Log.Logger.
boolSystem :: FilePath -> [CommandParam] -> IO Bool
boolSystem command params = boolSystem' command params id
@@ -56,7 +57,7 @@ boolSystemEnv :: FilePath -> [CommandParam] -> Maybe [(String, String)] -> IO Bo
boolSystemEnv command params environ = boolSystem' command params $
\p -> p { env = environ }
-{- Runs a system command, returning the exit status. -}
+-- | Runs a system command, returning the exit status.
safeSystem :: FilePath -> [CommandParam] -> IO ExitCode
safeSystem command params = safeSystem' command params id
@@ -71,23 +72,22 @@ safeSystemEnv :: FilePath -> [CommandParam] -> Maybe [(String, String)] -> IO Ex
safeSystemEnv command params environ = safeSystem' command params $
\p -> p { env = environ }
-{- Wraps a shell command line inside sh -c, allowing it to be run in a
- - login shell that may not support POSIX shell, eg csh. -}
+-- | Wraps a shell command line inside sh -c, allowing it to be run in a
+-- login shell that may not support POSIX shell, eg csh.
shellWrap :: String -> String
shellWrap cmdline = "sh -c " ++ shellEscape cmdline
-{- Escapes a filename or other parameter to be safely able to be exposed to
- - the shell.
- -
- - This method works for POSIX shells, as well as other shells like csh.
- -}
+-- | Escapes a filename or other parameter to be safely able to be exposed to
+-- the shell.
+--
+-- This method works for POSIX shells, as well as other shells like csh.
shellEscape :: String -> String
shellEscape f = "'" ++ escaped ++ "'"
where
-- replace ' with '"'"'
escaped = join "'\"'\"'" $ split "'" f
-{- Unescapes a set of shellEscaped words or filenames. -}
+-- | Unescapes a set of shellEscaped words or filenames.
shellUnEscape :: String -> [String]
shellUnEscape [] = []
shellUnEscape s = word : shellUnEscape rest
@@ -104,19 +104,19 @@ shellUnEscape s = word : shellUnEscape rest
| c == q = findword w cs
| otherwise = inquote q (w++[c]) cs
-{- For quickcheck. -}
+-- | For quickcheck.
prop_idempotent_shellEscape :: String -> Bool
prop_idempotent_shellEscape s = [s] == (shellUnEscape . shellEscape) s
prop_idempotent_shellEscape_multiword :: [String] -> Bool
prop_idempotent_shellEscape_multiword s = s == (shellUnEscape . unwords . map shellEscape) s
-{- Segments a list of filenames into groups that are all below the maximum
- - command-line length limit. -}
+-- | Segments a list of filenames into groups that are all below the maximum
+-- command-line length limit.
segmentXargsOrdered :: [FilePath] -> [[FilePath]]
segmentXargsOrdered = reverse . map reverse . segmentXargsUnordered
-{- Not preserving data is a little faster, and streams better when
- - there are a great many filesnames. -}
+-- | Not preserving order is a little faster, and streams better when
+-- there are a great many filenames.
segmentXargsUnordered :: [FilePath] -> [[FilePath]]
segmentXargsUnordered l = go l [] 0 []
where