{-# LINE 1 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
{-# LANGUAGE ForeignFunctionInterface #-}
{-# LINE 2 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
{-# OPTIONS_GHC -fno-warn-unused-imports #-}

{-# LINE 4 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
{-# LANGUAGE Trustworthy #-}

{-# LINE 6 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
-----------------------------------------------------------------------------
-- |
-- Module      :  System.Posix.Files.Common
-- Copyright   :  (c) The University of Glasgow 2002
-- License     :  BSD-style (see the file libraries/base/LICENSE)
-- 
-- Maintainer  :  libraries@haskell.org
-- Stability   :  provisional
-- Portability :  non-portable (requires POSIX)
--
-- Functions defined by the POSIX standards for manipulating and querying the
-- file system. Names of underlying POSIX functions are indicated whenever
-- possible. A more complete documentation of the POSIX functions together
-- with a more detailed description of different error conditions are usually
-- available in the system's manual pages or from
-- <http://www.unix.org/version3/online.html> (free registration required).
--
-- When a function that calls an underlying POSIX function fails, the errno
-- code is converted to an 'IOError' using 'Foreign.C.Error.errnoToIOError'.
-- For a list of which errno codes may be generated, consult the POSIX
-- documentation for the underlying function.
--
-----------------------------------------------------------------------------


{-# LINE 31 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

module System.Posix.Files.Common (
    -- * File modes
    -- FileMode exported by System.Posix.Types
    unionFileModes, intersectFileModes,
    nullFileMode,
    ownerReadMode, ownerWriteMode, ownerExecuteMode, ownerModes,
    groupReadMode, groupWriteMode, groupExecuteMode, groupModes,
    otherReadMode, otherWriteMode, otherExecuteMode, otherModes,
    setUserIDMode, setGroupIDMode,
    stdFileMode,   accessModes,
    fileTypeModes,
    blockSpecialMode, characterSpecialMode, namedPipeMode, regularFileMode,
    directoryMode, symbolicLinkMode, socketMode,

    -- ** Setting file modes
    setFdMode, setFileCreationMask,

    -- * File status
    FileStatus(..),
    -- ** Obtaining file status
    getFdStatus,
    -- ** Querying file status
    deviceID, fileID, fileMode, linkCount, fileOwner, fileGroup,
    specialDeviceID, fileSize, accessTime, modificationTime,
    statusChangeTime,
    isBlockDevice, isCharacterDevice, isNamedPipe, isRegularFile,
    isDirectory, isSymbolicLink, isSocket,

    -- * Setting file sizes
    setFdSize,

    -- * Changing file ownership
    setFdOwnerAndGroup,

    -- * Find system-specific limits for a file
    PathVar(..), getFdPathVar, pathVarConst,
  ) where

import System.Posix.Error
import System.Posix.Types
import System.IO.Unsafe
import Data.Bits
import System.Posix.Internals
import Foreign hiding (unsafePerformIO)
import Foreign.C

-- -----------------------------------------------------------------------------
-- POSIX file modes

-- The abstract type 'FileMode', constants and operators for
-- manipulating the file modes defined by POSIX.

-- | No permissions.
nullFileMode :: FileMode
nullFileMode = 0

-- | Owner has read permission.
ownerReadMode :: FileMode
ownerReadMode = (256)
{-# LINE 91 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Owner has write permission.
ownerWriteMode :: FileMode
ownerWriteMode = (128)
{-# LINE 95 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Owner has execute permission.
ownerExecuteMode :: FileMode
ownerExecuteMode = (64)
{-# LINE 99 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Group has read permission.
groupReadMode :: FileMode
groupReadMode = (32)
{-# LINE 103 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Group has write permission.
groupWriteMode :: FileMode
groupWriteMode = (16)
{-# LINE 107 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Group has execute permission.
groupExecuteMode :: FileMode
groupExecuteMode = (8)
{-# LINE 111 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Others have read permission.
otherReadMode :: FileMode
otherReadMode = (4)
{-# LINE 115 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Others have write permission.
otherWriteMode :: FileMode
otherWriteMode = (2)
{-# LINE 119 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Others have execute permission.
otherExecuteMode :: FileMode
otherExecuteMode = (1)
{-# LINE 123 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Set user ID on execution.
setUserIDMode :: FileMode
setUserIDMode = (2048)
{-# LINE 127 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Set group ID on execution.
setGroupIDMode :: FileMode
setGroupIDMode = (1024)
{-# LINE 131 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Owner, group and others have read and write permission.
stdFileMode :: FileMode
stdFileMode = ownerReadMode  .|. ownerWriteMode .|. 
	      groupReadMode  .|. groupWriteMode .|. 
	      otherReadMode  .|. otherWriteMode

-- | Owner has read, write and execute permission.
ownerModes :: FileMode
ownerModes = (448)
{-# LINE 141 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Group has read, write and execute permission.
groupModes :: FileMode
groupModes = (56)
{-# LINE 145 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Others have read, write and execute permission.
otherModes :: FileMode
otherModes = (7)
{-# LINE 149 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Owner, group and others have read, write and execute permission.
accessModes :: FileMode
accessModes = ownerModes .|. groupModes .|. otherModes

-- | Combines the two file modes into one that contains modes that appear in
-- either.
unionFileModes :: FileMode -> FileMode -> FileMode
unionFileModes m1 m2 = m1 .|. m2

-- | Combines two file modes into one that only contains modes that appear in
-- both.
intersectFileModes :: FileMode -> FileMode -> FileMode
intersectFileModes m1 m2 = m1 .&. m2

fileTypeModes :: FileMode
fileTypeModes = (61440)
{-# LINE 166 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

blockSpecialMode :: FileMode
blockSpecialMode = (24576)
{-# LINE 169 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

characterSpecialMode :: FileMode
characterSpecialMode = (8192)
{-# LINE 172 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

namedPipeMode :: FileMode
namedPipeMode = (4096)
{-# LINE 175 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

regularFileMode :: FileMode
regularFileMode = (32768)
{-# LINE 178 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

directoryMode :: FileMode
directoryMode = (16384)
{-# LINE 181 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

symbolicLinkMode :: FileMode
symbolicLinkMode = (40960)
{-# LINE 184 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

socketMode :: FileMode
socketMode = (49152)
{-# LINE 187 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | @setFdMode fd mode@ acts like 'setFileMode' but uses a file descriptor
-- @fd@ instead of a 'FilePath'.
--
-- Note: calls @fchmod@.
setFdMode :: Fd -> FileMode -> IO ()
setFdMode (Fd fd) m =
  throwErrnoIfMinus1_ "setFdMode" (c_fchmod fd m)

foreign import ccall unsafe "fchmod" 
  c_fchmod :: CInt -> CMode -> IO CInt

-- | @setFileCreationMask mode@ sets the file mode creation mask to @mode@.
-- Modes set by this operation are subtracted from files and directories upon
-- creation. The previous file creation mask is returned.
--
-- Note: calls @umask@.
setFileCreationMask :: FileMode -> IO FileMode
setFileCreationMask mask = c_umask mask

-- -----------------------------------------------------------------------------
-- stat() support

-- | POSIX defines operations to get information, such as owner, permissions,
-- size and access times, about a file. This information is represented by the
-- 'FileStatus' type.
--
-- Note: see @chmod@.
newtype FileStatus = FileStatus (ForeignPtr CStat)

-- | ID of the device on which this file resides.
deviceID         :: FileStatus -> DeviceID
-- | inode number
fileID           :: FileStatus -> FileID
-- | File mode (such as permissions).
fileMode         :: FileStatus -> FileMode
-- | Number of hard links to this file.
linkCount        :: FileStatus -> LinkCount
-- | ID of owner.
fileOwner        :: FileStatus -> UserID
-- | ID of group.
fileGroup        :: FileStatus -> GroupID
-- | Describes the device that this file represents.
specialDeviceID  :: FileStatus -> DeviceID
-- | Size of the file in bytes. If this file is a symbolic link the size is
-- the length of the pathname it contains.
fileSize         :: FileStatus -> FileOffset
-- | Time of last access.
accessTime       :: FileStatus -> EpochTime
-- | Time of last modification.
modificationTime :: FileStatus -> EpochTime
-- | Time of last status change (i.e. owner, group, link count, mode, etc.).
statusChangeTime :: FileStatus -> EpochTime

deviceID (FileStatus stat) = 
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 0))
{-# LINE 243 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
fileID (FileStatus stat) = 
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 8))
{-# LINE 245 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
fileMode (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 24))
{-# LINE 247 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
linkCount (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 16))
{-# LINE 249 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
fileOwner (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 28))
{-# LINE 251 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
fileGroup (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 32))
{-# LINE 253 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
specialDeviceID (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 40))
{-# LINE 255 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
fileSize (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 48))
{-# LINE 257 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
accessTime (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 72))
{-# LINE 259 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
modificationTime (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 88))
{-# LINE 261 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
statusChangeTime (FileStatus stat) =
  unsafePerformIO $ withForeignPtr stat $ ((\hsc_ptr -> peekByteOff hsc_ptr 104))
{-# LINE 263 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | Checks if this file is a block device.
isBlockDevice     :: FileStatus -> Bool
-- | Checks if this file is a character device.
isCharacterDevice :: FileStatus -> Bool
-- | Checks if this file is a named pipe device.
isNamedPipe       :: FileStatus -> Bool
-- | Checks if this file is a regular file device.
isRegularFile     :: FileStatus -> Bool
-- | Checks if this file is a directory device.
isDirectory       :: FileStatus -> Bool
-- | Checks if this file is a symbolic link device.
isSymbolicLink    :: FileStatus -> Bool
-- | Checks if this file is a socket device.
isSocket          :: FileStatus -> Bool

isBlockDevice stat = 
  (fileMode stat `intersectFileModes` fileTypeModes) == blockSpecialMode
isCharacterDevice stat = 
  (fileMode stat `intersectFileModes` fileTypeModes) == characterSpecialMode
isNamedPipe stat = 
  (fileMode stat `intersectFileModes` fileTypeModes) == namedPipeMode
isRegularFile stat = 
  (fileMode stat `intersectFileModes` fileTypeModes) == regularFileMode
isDirectory stat = 
  (fileMode stat `intersectFileModes` fileTypeModes) == directoryMode
isSymbolicLink stat = 
  (fileMode stat `intersectFileModes` fileTypeModes) == symbolicLinkMode
isSocket stat = 
  (fileMode stat `intersectFileModes` fileTypeModes) == socketMode

-- | @getFdStatus fd@ acts as 'getFileStatus' but uses a file descriptor @fd@.
--
-- Note: calls @fstat@.
getFdStatus :: Fd -> IO FileStatus
getFdStatus (Fd fd) = do
  fp <- mallocForeignPtrBytes (144) 
{-# LINE 300 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
  withForeignPtr fp $ \p ->
    throwErrnoIfMinus1_ "getFdStatus" (c_fstat fd p)
  return (FileStatus fp)

-- -----------------------------------------------------------------------------
-- fchown()

-- | Acts as 'setOwnerAndGroup' but uses a file descriptor instead of a
-- 'FilePath'.
--
-- Note: calls @fchown@.
setFdOwnerAndGroup :: Fd -> UserID -> GroupID -> IO ()
setFdOwnerAndGroup (Fd fd) uid gid = 
  throwErrnoIfMinus1_ "setFdOwnerAndGroup" (c_fchown fd uid gid)

foreign import ccall unsafe "fchown"
  c_fchown :: CInt -> CUid -> CGid -> IO CInt

-- -----------------------------------------------------------------------------
-- ftruncate()

-- | Acts as 'setFileSize' but uses a file descriptor instead of a 'FilePath'.
--
-- Note: calls @ftruncate@.
setFdSize :: Fd -> FileOffset -> IO ()
setFdSize (Fd fd) off =
  throwErrnoIfMinus1_ "setFdSize" (c_ftruncate fd off)

-- -----------------------------------------------------------------------------
-- pathconf()/fpathconf() support

data PathVar
  = FileSizeBits		  {- _PC_FILESIZEBITS     -}
  | LinkLimit                     {- _PC_LINK_MAX         -}
  | InputLineLimit                {- _PC_MAX_CANON        -}
  | InputQueueLimit               {- _PC_MAX_INPUT        -}
  | FileNameLimit                 {- _PC_NAME_MAX         -}
  | PathNameLimit                 {- _PC_PATH_MAX         -}
  | PipeBufferLimit               {- _PC_PIPE_BUF         -}
				  -- These are described as optional in POSIX:
  				  {- _PC_ALLOC_SIZE_MIN     -}
  				  {- _PC_REC_INCR_XFER_SIZE -}
  				  {- _PC_REC_MAX_XFER_SIZE  -}
  				  {- _PC_REC_MIN_XFER_SIZE  -}
 				  {- _PC_REC_XFER_ALIGN     -}
  | SymbolicLinkLimit		  {- _PC_SYMLINK_MAX      -}
  | SetOwnerAndGroupIsRestricted  {- _PC_CHOWN_RESTRICTED -}
  | FileNamesAreNotTruncated      {- _PC_NO_TRUNC         -}
  | VDisableChar		  {- _PC_VDISABLE         -}
  | AsyncIOAvailable		  {- _PC_ASYNC_IO         -}
  | PrioIOAvailable		  {- _PC_PRIO_IO          -}
  | SyncIOAvailable		  {- _PC_SYNC_IO          -}

pathVarConst :: PathVar -> CInt
pathVarConst v = case v of
	LinkLimit     			-> (0)
{-# LINE 356 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	InputLineLimit			-> (1)
{-# LINE 357 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	InputQueueLimit			-> (2)
{-# LINE 358 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	FileNameLimit			-> (3)
{-# LINE 359 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	PathNameLimit			-> (4)
{-# LINE 360 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	PipeBufferLimit			-> (5)
{-# LINE 361 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	SetOwnerAndGroupIsRestricted	-> (6)
{-# LINE 362 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	FileNamesAreNotTruncated	-> (7)
{-# LINE 363 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	VDisableChar			-> (8)
{-# LINE 364 "libraries/unix/./System/Posix/Files/Common.hsc" #-}


{-# LINE 366 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	SyncIOAvailable		-> (9)
{-# LINE 367 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

{-# LINE 370 "libraries/unix/./System/Posix/Files/Common.hsc" #-}


{-# LINE 372 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	AsyncIOAvailable	-> (10)
{-# LINE 373 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

{-# LINE 376 "libraries/unix/./System/Posix/Files/Common.hsc" #-}


{-# LINE 378 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	PrioIOAvailable		-> (11)
{-# LINE 379 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

{-# LINE 382 "libraries/unix/./System/Posix/Files/Common.hsc" #-}


{-# LINE 386 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	FileSizeBits		-> error "_PC_FILESIZEBITS not available"

{-# LINE 388 "libraries/unix/./System/Posix/Files/Common.hsc" #-}


{-# LINE 392 "libraries/unix/./System/Posix/Files/Common.hsc" #-}
	SymbolicLinkLimit	-> error "_PC_SYMLINK_MAX not available"

{-# LINE 394 "libraries/unix/./System/Posix/Files/Common.hsc" #-}

-- | @getFdPathVar var fd@ obtains the dynamic value of the requested
-- configurable file limit or option associated with the file or directory
-- attached to the open channel @fd@. For defined file limits, @getFdPathVar@
-- returns the associated value.  For defined file options, the result of
-- @getFdPathVar@ is undefined, but not failure.
--
-- Note: calls @fpathconf@.
getFdPathVar :: Fd -> PathVar -> IO Limit
getFdPathVar (Fd fd) v =
    throwErrnoIfMinus1 "getFdPathVar" $ 
      c_fpathconf fd (pathVarConst v)

foreign import ccall unsafe "fpathconf" 
  c_fpathconf :: CInt -> CInt -> IO CLong