diff options
Diffstat (limited to 'Utility/Process.hs')
| -rw-r--r-- | Utility/Process.hs | 207 |
1 files changed, 125 insertions, 82 deletions
diff --git a/Utility/Process.hs b/Utility/Process.hs index e25618e..c669996 100644 --- a/Utility/Process.hs +++ b/Utility/Process.hs @@ -1,18 +1,20 @@ {- System.Process enhancements, including additional ways of running - processes, and logging. - - - Copyright 2012 Joey Hess <joey@kitenet.net> + - Copyright 2012-2015 Joey Hess <id@joeyh.name> - - License: BSD-2-clause -} {-# LANGUAGE CPP, Rank2Types #-} +{-# OPTIONS_GHC -fno-warn-tabs #-} module Utility.Process ( module X, CreateProcess(..), StdHandle(..), readProcess, + readProcess', readProcessEnv, writeReadProcessEnv, forceSuccessProcess, @@ -24,21 +26,27 @@ module Utility.Process ( processTranscript, processTranscript', withHandle, - withBothHandles, + withIOHandles, + withOEHandles, withQuietOutput, + feedWithQuietOutput, createProcess, + waitForProcess, startInteractiveProcess, stdinHandle, stdoutHandle, stderrHandle, - bothHandles, + ioHandles, processHandle, devNull, ) where -import qualified System.Process -import System.Process as X hiding (CreateProcess(..), createProcess, runInteractiveProcess, readProcess, readProcessWithExitCode, system, rawSystem, runInteractiveCommand, runProcess) -import System.Process hiding (createProcess, readProcess) +import qualified Utility.Process.Shim +import qualified Utility.Process.Shim as X hiding (CreateProcess(..), createProcess, runInteractiveProcess, readProcess, readProcessWithExitCode, system, rawSystem, runInteractiveCommand, runProcess) +import Utility.Process.Shim hiding (createProcess, readProcess, waitForProcess) +import Utility.Misc +import Utility.Exception + import System.Exit import System.IO import System.Log.Logger @@ -46,40 +54,39 @@ import Control.Concurrent import qualified Control.Exception as E import Control.Monad #ifndef mingw32_HOST_OS -import System.Posix.IO +import qualified System.Posix.IO #else import Control.Applicative #endif import Data.Maybe - -import Utility.Misc -import Utility.Exception +import Prelude type CreateProcessRunner = forall a. CreateProcess -> ((Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) -> IO a) -> IO a data StdHandle = StdinHandle | StdoutHandle | StderrHandle deriving (Eq) -{- Normally, when reading from a process, it does not need to be fed any - - standard input. -} +-- | Normally, when reading from a process, it does not need to be fed any +-- standard input. readProcess :: FilePath -> [String] -> IO String readProcess cmd args = readProcessEnv cmd args Nothing readProcessEnv :: FilePath -> [String] -> Maybe [(String, String)] -> IO String -readProcessEnv cmd args environ = - withHandle StdoutHandle createProcessSuccess p $ \h -> do - output <- hGetContentsStrict h - hClose h - return output +readProcessEnv cmd args environ = readProcess' p where p = (proc cmd args) { std_out = CreatePipe , env = environ } -{- Runs an action to write to a process on its stdin, - - returns its output, and also allows specifying the environment. - -} +readProcess' :: CreateProcess -> IO String +readProcess' p = withHandle StdoutHandle createProcessSuccess p $ \h -> do + output <- hGetContentsStrict h + hClose h + return output + +-- | Runs an action to write to a process on its stdin, +-- returns its output, and also allows specifying the environment. writeReadProcessEnv :: FilePath -> [String] @@ -119,8 +126,8 @@ writeReadProcessEnv cmd args environ writestdin adjusthandle = do , env = environ } -{- Waits for a ProcessHandle, and throws an IOError if the process - - did not exit successfully. -} +-- | Waits for a ProcessHandle, and throws an IOError if the process +-- did not exit successfully. forceSuccessProcess :: CreateProcess -> ProcessHandle -> IO () forceSuccessProcess p pid = do code <- waitForProcess pid @@ -128,10 +135,10 @@ forceSuccessProcess p pid = do ExitSuccess -> return () ExitFailure n -> fail $ showCmd p ++ " exited " ++ show n -{- Waits for a ProcessHandle and returns True if it exited successfully. - - Note that using this with createProcessChecked will throw away - - the Bool, and is only useful to ignore the exit code of a process, - - while still waiting for it. -} +-- | Waits for a ProcessHandle and returns True if it exited successfully. +-- Note that using this with createProcessChecked will throw away +-- the Bool, and is only useful to ignore the exit code of a process, +-- while still waiting for it. -} checkSuccessProcess :: ProcessHandle -> IO Bool checkSuccessProcess pid = do code <- waitForProcess pid @@ -142,13 +149,13 @@ ignoreFailureProcess pid = do void $ waitForProcess pid return True -{- Runs createProcess, then an action on its handles, and then - - forceSuccessProcess. -} +-- | Runs createProcess, then an action on its handles, and then +-- forceSuccessProcess. createProcessSuccess :: CreateProcessRunner createProcessSuccess p a = createProcessChecked (forceSuccessProcess p) p a -{- Runs createProcess, then an action on its handles, and then - - a checker action on its exit code, which must wait for the process. -} +-- | Runs createProcess, then an action on its handles, and then +-- a checker action on its exit code, which must wait for the process. createProcessChecked :: (ProcessHandle -> IO b) -> CreateProcessRunner createProcessChecked checker p a = do t@(_, _, _, pid) <- createProcess p @@ -156,31 +163,30 @@ createProcessChecked checker p a = do _ <- checker pid either E.throw return r -{- Leaves the process running, suitable for lazy streaming. - - Note: Zombies will result, and must be waited on. -} +-- | Leaves the process running, suitable for lazy streaming. +-- Note: Zombies will result, and must be waited on. createBackgroundProcess :: CreateProcessRunner createBackgroundProcess p a = a =<< createProcess p -{- Runs a process, optionally feeding it some input, and - - returns a transcript combining its stdout and stderr, and - - whether it succeeded or failed. -} +-- | Runs a process, optionally feeding it some input, and +-- returns a transcript combining its stdout and stderr, and +-- whether it succeeded or failed. processTranscript :: String -> [String] -> (Maybe String) -> IO (String, Bool) -processTranscript cmd opts input = processTranscript' cmd opts Nothing input +processTranscript = processTranscript' id -processTranscript' :: String -> [String] -> Maybe [(String, String)] -> (Maybe String) -> IO (String, Bool) -processTranscript' cmd opts environ input = do +processTranscript' :: (CreateProcess -> CreateProcess) -> String -> [String] -> Maybe String -> IO (String, Bool) +processTranscript' modproc cmd opts input = do #ifndef mingw32_HOST_OS {- This implementation interleves stdout and stderr in exactly the order - the process writes them. -} - (readf, writef) <- createPipe - readh <- fdToHandle readf - writeh <- fdToHandle writef - p@(_, _, _, pid) <- createProcess $ + (readf, writef) <- System.Posix.IO.createPipe + readh <- System.Posix.IO.fdToHandle readf + writeh <- System.Posix.IO.fdToHandle writef + p@(_, _, _, pid) <- createProcess $ modproc $ (proc cmd opts) { std_in = if isJust input then CreatePipe else Inherit , std_out = UseHandle writeh , std_err = UseHandle writeh - , env = environ } hClose writeh @@ -192,12 +198,11 @@ processTranscript' cmd opts environ input = do return (transcript, ok) #else {- This implementation for Windows puts stderr after stdout. -} - p@(_, _, _, pid) <- createProcess $ + p@(_, _, _, pid) <- createProcess $ modproc $ (proc cmd opts) { std_in = if isJust input then CreatePipe else Inherit , std_out = CreatePipe , std_err = CreatePipe - , env = environ } getout <- mkreader (stdoutHandle p) @@ -227,9 +232,9 @@ processTranscript' cmd opts environ input = do hClose inh writeinput Nothing _ = return () -{- Runs a CreateProcessRunner, on a CreateProcess structure, that - - is adjusted to pipe only from/to a single StdHandle, and passes - - the resulting Handle to an action. -} +-- | Runs a CreateProcessRunner, on a CreateProcess structure, that +-- is adjusted to pipe only from/to a single StdHandle, and passes +-- the resulting Handle to an action. withHandle :: StdHandle -> CreateProcessRunner @@ -251,13 +256,13 @@ withHandle h creator p a = creator p' $ a . select | h == StderrHandle = (stderrHandle, base { std_err = CreatePipe }) -{- Like withHandle, but passes (stdin, stdout) handles to the action. -} -withBothHandles +-- | Like withHandle, but passes (stdin, stdout) handles to the action. +withIOHandles :: CreateProcessRunner -> CreateProcess -> ((Handle, Handle) -> IO a) -> IO a -withBothHandles creator p a = creator p' $ a . bothHandles +withIOHandles creator p a = creator p' $ a . ioHandles where p' = p { std_in = CreatePipe @@ -265,8 +270,22 @@ withBothHandles creator p a = creator p' $ a . bothHandles , std_err = Inherit } -{- Forces the CreateProcessRunner to run quietly; - - both stdout and stderr are discarded. -} +-- | Like withHandle, but passes (stdout, stderr) handles to the action. +withOEHandles + :: CreateProcessRunner + -> CreateProcess + -> ((Handle, Handle) -> IO a) + -> IO a +withOEHandles creator p a = creator p' $ a . oeHandles + where + p' = p + { std_in = Inherit + , std_out = CreatePipe + , std_err = CreatePipe + } + +-- | Forces the CreateProcessRunner to run quietly; +-- both stdout and stderr are discarded. withQuietOutput :: CreateProcessRunner -> CreateProcess @@ -278,6 +297,21 @@ withQuietOutput creator p = withFile devNull WriteMode $ \nullh -> do } creator p' $ const $ return () +-- | Stdout and stderr are discarded, while the process is fed stdin +-- from the handle. +feedWithQuietOutput + :: CreateProcessRunner + -> CreateProcess + -> (Handle -> IO a) + -> IO a +feedWithQuietOutput creator p a = withFile devNull WriteMode $ \nullh -> do + let p' = p + { std_in = CreatePipe + , std_out = UseHandle nullh + , std_err = UseHandle nullh + } + creator p' $ a . stdinHandle + devNull :: FilePath #ifndef mingw32_HOST_OS devNull = "/dev/null" @@ -285,11 +319,11 @@ devNull = "/dev/null" devNull = "NUL" #endif -{- Extract a desired handle from createProcess's tuple. - - These partial functions are safe as long as createProcess is run - - with appropriate parameters to set up the desired handle. - - Get it wrong and the runtime crash will always happen, so should be - - easily noticed. -} +-- | Extract a desired handle from createProcess's tuple. +-- These partial functions are safe as long as createProcess is run +-- with appropriate parameters to set up the desired handle. +-- Get it wrong and the runtime crash will always happen, so should be +-- easily noticed. type HandleExtractor = (Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) -> Handle stdinHandle :: HandleExtractor stdinHandle (Just h, _, _, _) = h @@ -300,38 +334,25 @@ stdoutHandle _ = error "expected stdoutHandle" stderrHandle :: HandleExtractor stderrHandle (_, _, Just h, _) = h stderrHandle _ = error "expected stderrHandle" -bothHandles :: (Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) -> (Handle, Handle) -bothHandles (Just hin, Just hout, _, _) = (hin, hout) -bothHandles _ = error "expected bothHandles" +ioHandles :: (Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) -> (Handle, Handle) +ioHandles (Just hin, Just hout, _, _) = (hin, hout) +ioHandles _ = error "expected ioHandles" +oeHandles :: (Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) -> (Handle, Handle) +oeHandles (_, Just hout, Just herr, _) = (hout, herr) +oeHandles _ = error "expected oeHandles" processHandle :: (Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) -> ProcessHandle processHandle (_, _, _, pid) = pid -{- Debugging trace for a CreateProcess. -} -debugProcess :: CreateProcess -> IO () -debugProcess p = do - debugM "Utility.Process" $ unwords - [ action ++ ":" - , showCmd p - ] - where - action - | piped (std_in p) && piped (std_out p) = "chat" - | piped (std_in p) = "feed" - | piped (std_out p) = "read" - | otherwise = "call" - piped Inherit = False - piped _ = True - -{- Shows the command that a CreateProcess will run. -} +-- | Shows the command that a CreateProcess will run. showCmd :: CreateProcess -> String showCmd = go . cmdspec where go (ShellCommand s) = s go (RawCommand c ps) = c ++ " " ++ show ps -{- Starts an interactive process. Unlike runInteractiveProcess in - - System.Process, stderr is inherited. -} +-- | Starts an interactive process. Unlike runInteractiveProcess in +-- System.Process, stderr is inherited. startInteractiveProcess :: FilePath -> [String] @@ -347,8 +368,30 @@ startInteractiveProcess cmd args environ = do (Just from, Just to, _, pid) <- createProcess p return (pid, to, from) -{- Wrapper around System.Process function that does debug logging. -} +-- | Wrapper around 'System.Process.createProcess' that does debug logging. createProcess :: CreateProcess -> IO (Maybe Handle, Maybe Handle, Maybe Handle, ProcessHandle) createProcess p = do debugProcess p - System.Process.createProcess p + Utility.Process.Shim.createProcess p + +-- | Debugging trace for a CreateProcess. +debugProcess :: CreateProcess -> IO () +debugProcess p = debugM "Utility.Process" $ unwords + [ action ++ ":" + , showCmd p + ] + where + action + | piped (std_in p) && piped (std_out p) = "chat" + | piped (std_in p) = "feed" + | piped (std_out p) = "read" + | otherwise = "call" + piped Inherit = False + piped _ = True + +-- | Wrapper around 'System.Process.waitForProcess' that does debug logging. +waitForProcess :: ProcessHandle -> IO ExitCode +waitForProcess h = do + r <- Utility.Process.Shim.waitForProcess h + debugM "Utility.Process" ("process done " ++ show r) + return r |