diff --git a/LICENSE b/LICENSE --- a/LICENSE +++ b/LICENSE @@ -1,31 +1,31 @@ -Copyright (c) 2011, Michael Steele -Copyright (c) 2000, Mikael Nordell - -All rights reserved. - -Redistribution and use in source and binary forms, with or without -modification, are permitted provided that the following conditions are met: - - * Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - - * Redistributions in binary form must reproduce the above - copyright notice, this list of conditions and the following - disclaimer in the documentation and/or other materials provided - with the distribution. - - * Neither the name of Michael Steele nor the names of other - contributors may be used to endorse or promote products derived - from this software without specific prior written permission. - -THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +Copyright (c) 2011-2013, Michael Steele +Copyright (c) 2000, Mikael Nordell + +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following + disclaimer in the documentation and/or other materials provided + with the distribution. + + * Neither the name of Michael Steele nor the names of other + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/Setup.hs b/Setup.hs --- a/Setup.hs +++ b/Setup.hs @@ -1,2 +1,2 @@ -import Distribution.Simple -main = defaultMain +import Distribution.Simple +main = defaultMain diff --git a/System/Win32/JunctionPoint.hs b/System/Win32/JunctionPoint.hs --- a/System/Win32/JunctionPoint.hs +++ b/System/Win32/JunctionPoint.hs @@ -1,331 +1,333 @@ -{-# LANGUAGE ForeignFunctionInterface #-} - -module System.Win32.JunctionPoint - ( createJunctionPoint - , deleteJunctionPoint - , getJunctionPointInfo - ) where - -import Control.Exception (bracket) -import Data.Bits -import Data.Char (chr) -import Data.Text (Text) -import qualified Data.Text as T -import Data.Text.Foreign -import Foreign -import Foreign.C -import System.Win32 hiding (createFile) - --- Macro taken from winioctl.h --- #define CTL_CODE( DeviceType, Function, Method, Access) ( \ --- (DWORD) ((DeviceType) << 16 | ((Access) << 14) | ((Function) << 2) \ --- | (Method)) -cTL_CODE :: DWORD -> DWORD -> DWORD -> DWORD -> DWORD -cTL_CODE d f m a = d `shift` 16 .|. a `shift` 14 .|. f `shift` 2 .|. m - --- taken from winioctl.h -fILE_DEVICE_FILE_SYSTEM :: DWORD -fILE_DEVICE_FILE_SYSTEM = 0x00000009 - --- taken from winioctl.h -mETHOD_BUFFERED :: DWORD -mETHOD_BUFFERED = 0 - --- taken from winioctl.h -fILE_ANY_ACCESS, fILE_SPECIAL_ACCESS :: DWORD -fILE_ANY_ACCESS = 0 -fILE_SPECIAL_ACCESS = 0 - --- taken from winioctl.h -fSCTL_SET_REPARSE_POINT :: DWORD -fSCTL_SET_REPARSE_POINT = cTL_CODE fILE_DEVICE_FILE_SYSTEM 41 - mETHOD_BUFFERED fILE_SPECIAL_ACCESS -fSCTL_GET_REPARSE_POINT :: DWORD -fSCTL_GET_REPARSE_POINT = cTL_CODE fILE_DEVICE_FILE_SYSTEM 42 - mETHOD_BUFFERED fILE_ANY_ACCESS -fSCTL_DELETE_REPARSE_POINT :: DWORD -fSCTL_DELETE_REPARSE_POINT = cTL_CODE fILE_DEVICE_FILE_SYSTEM 43 - mETHOD_BUFFERED fILE_SPECIAL_ACCESS - -iO_REPARSE_TAG_MOUNT_POINT :: DWORD -iO_REPARSE_TAG_MOUNT_POINT = 0xA0000003 - ---taken from MSDN's OpenFileById documentation -fILE_FLAG_OPEN_REPARSE_POINT :: DWORD -fILE_FLAG_OPEN_REPARSE_POINT = 0x00200000 - -mAXIMUM_REPARSE_DATA_BUFFER_SIZE :: Int -mAXIMUM_REPARSE_DATA_BUFFER_SIZE = 16 * 1024 - --- The first 3 fields of TMN_REPARSE_DATA_BUFFER are considered the --- header. This is used in setReparsePoint. -tMN_REPARSE_DATA_BUFFER_HEADER_SIZE :: DWORD -tMN_REPARSE_DATA_BUFFER_HEADER_SIZE = 8 - --- C structure. This is not documented in current versions of the --- Windows SDK. - --- struct TMN_REPARSE_DATA_BUFFER --- { --- DWORD ReparseTag; --- WORD ReparseDataLength; --- WORD Reserved; --- WORD SubstituteNameOffset; --- WORD SubstituteNameLength; --- WORD PrintNameOffset; --- WORD PrintNameLength; --- WCHAR PathBuffer[1]; --- }; - -data TMN_REPARSE_DATA_BUFFER = TMN_REPARSE_DATA_BUFFER - { _reparseTag :: !DWORD - -- Bytes in addition to first 8. This will be 12 + length of _pathBuffer - , _reparseDataLength :: !WORD - , _reserved :: !WORD - , _substituteNameOffset :: !WORD - , _substituteNameLength :: !WORD - , _printNameOffset :: !WORD - , _printNameLength :: !WORD - -- The C struct indicates a single-element array. - -- Actually, we need to allocate enough memory to - -- hold a string here. - , _pathBuffer :: !(Ptr CWchar) - } - -instance Storable TMN_REPARSE_DATA_BUFFER where - -- Storable does not allow the pokes of different sizes, so we're just - -- allocating the maximum size Microsoft documents. - sizeOf _ = mAXIMUM_REPARSE_DATA_BUFFER_SIZE - alignment _ = 1 -- no alignment? I don't know what this means. - peek ptr = do - reparseTag <- peek . castPtr $ ptr - reparseDataLength <- castPtr ptr `peekByteOff` 4 - reserved <- castPtr ptr `peekByteOff` 6 - substituteNameOffset <- castPtr ptr `peekByteOff` 8 - substituteNameLength <- castPtr ptr `peekByteOff` 10 - printNameOffset <- castPtr ptr `peekByteOff` 12 - printNameLength <- castPtr ptr `peekByteOff` 14 - let pathBuffer = castPtr ptr `plusPtr` 16 - return $ TMN_REPARSE_DATA_BUFFER reparseTag reparseDataLength reserved - substituteNameOffset substituteNameLength printNameOffset - printNameLength pathBuffer - poke ptr rdb = do - castPtr ptr `poke` _reparseTag rdb - castPtr ptr `pokeByteOff` 4 $ _reparseDataLength rdb - castPtr ptr `pokeByteOff` 6 $ _reserved rdb - castPtr ptr `pokeByteOff` 8 $ _substituteNameOffset rdb - castPtr ptr `pokeByteOff` 10 $ _substituteNameLength rdb - castPtr ptr `pokeByteOff` 12 $ _printNameOffset rdb - castPtr ptr `pokeByteOff` 14 $ _printNameLength rdb - strLen <- lengthArray0 0 $ _pathBuffer rdb - copyArray (ptr `plusPtr` 16) (_pathBuffer rdb) (strLen + 1) - --- This data structure is almost identical to TMN_REPARSE_DATA_BUFFER, but the --- meaning of fields differ. Microsoft documents this structure. It is --- used for querying existing reparse points. -data REPARSE_GUID_DATA_BUFFER = REPARSE_GUID_DATA_BUFFER - { _rgdb_ReparseTag :: DWORD - -- Bytes used by _rgdb_DataBuffer. Contrast this with TMN_REPARSE_DATA_BUFFER. - , _rgdb_ReparseDataLength :: !WORD - , _rgdb_Reserved :: !WORD - -- MS specifies an odd structure, but a GUID is really just a 128-bit - -- value. - , _rgdb_GUID1 :: !DWORD - , _rgdb_GUID2 :: !DWORD - , _rgdb_GUID3 :: !DWORD - , _rgdb_GUID4 :: !DWORD - -- The C struct indicates a single-element array. - -- Actually, we need to allocate enough memory to - -- hold a string here. - , _rgdb_DataBuffer :: !(Ptr BYTE) - } - -instance Storable REPARSE_GUID_DATA_BUFFER where - -- Storable does not allow the pokes of different sizes, so we're just - -- allocating the maximum size Microsoft documents. - sizeOf _ = mAXIMUM_REPARSE_DATA_BUFFER_SIZE - alignment _ = 1 -- no alignment? I don't know what this means. - peek ptr = do - _rgdb_ReparseTag <- peek . castPtr $ ptr - _rgdb_ReparseDataLength <- castPtr ptr `peekByteOff` 4 - _rgdb_Reserved <- castPtr ptr `peekByteOff` 6 - _rgdb_GUID1 <- castPtr ptr `peekByteOff` 8 - _rgdb_GUID2 <- castPtr ptr `peekByteOff` 12 - _rgdb_GUID3 <- castPtr ptr `peekByteOff` 16 - _rgdb_GUID4 <- castPtr ptr `peekByteOff` 20 - let dataBuffer = castPtr ptr `plusPtr` 24 - return $ REPARSE_GUID_DATA_BUFFER _rgdb_ReparseTag - _rgdb_ReparseDataLength _rgdb_Reserved _rgdb_GUID1 _rgdb_GUID2 - _rgdb_GUID3 _rgdb_GUID4 dataBuffer - poke ptr rdb = do - castPtr ptr `poke` _rgdb_ReparseTag rdb - castPtr ptr `pokeByteOff` 4 $ _rgdb_ReparseDataLength rdb - castPtr ptr `pokeByteOff` 6 $ _rgdb_Reserved rdb - castPtr ptr `pokeByteOff` 8 $ _rgdb_GUID1 rdb - castPtr ptr `pokeByteOff` 12 $ _rgdb_GUID2 rdb - castPtr ptr `pokeByteOff` 16 $ _rgdb_GUID3 rdb - castPtr ptr `pokeByteOff` 20 $ _rgdb_GUID4 rdb - buffer <- peekArray bufferSize (_rgdb_DataBuffer rdb) - plusPtr ptr 24 `pokeArray` buffer - where - bufferSize = fromIntegral $ _rgdb_ReparseDataLength rdb - 24 - -withTMN_REPARSE_DATA_BUFFER :: Text - -> (Ptr TMN_REPARSE_DATA_BUFFER -> IO a) -> IO a -withTMN_REPARSE_DATA_BUFFER dst f = - useAsPtr0 dst $ \c_dst -> - with (TMN_REPARSE_DATA_BUFFER - { _reparseTag = iO_REPARSE_TAG_MOUNT_POINT - , _reparseDataLength = dstLen + 12 - , _reserved = 0 - , _substituteNameOffset = 0 - , _substituteNameLength = dstLen - , _printNameOffset = dstLen + 2 - , _printNameLength = 0 - , _pathBuffer = c_dst - }) f - where - dstLen = fromIntegral (T.length dst) * 2 - -withREPARSE_GUID_DATA_BUFFER :: [BYTE] - -> (Ptr REPARSE_GUID_DATA_BUFFER -> IO a) -> IO a -withREPARSE_GUID_DATA_BUFFER bx f = - withArray bx $ \dataBuffer -> - with (REPARSE_GUID_DATA_BUFFER - { _rgdb_ReparseTag = iO_REPARSE_TAG_MOUNT_POINT - -- must be 0 when deleting a junction point - , _rgdb_ReparseDataLength = 0 - , _rgdb_Reserved = 0 - , _rgdb_GUID1 = 0 - , _rgdb_GUID2 = 0 - , _rgdb_GUID3 = 0 - , _rgdb_GUID4 = 0 - , _rgdb_DataBuffer = dataBuffer - }) f - --- | Create a junction point between two folders on the same filesystem. --- --- 'mountDir' should be the full file path to an empty folder. This --- folder should be on a local filesystem. --- --- 'destDir' should be the full file path to the junction point's target. The --- target must be a folder on the same filesystem as its source. The path --- should also be preceeded by \"\\??\\\". This indicates to Windows not to try --- validating the path before using it. --- --- >>> createJunctionPoint "c:\\Windows\\System32" "\\??\\c:\\System32" -createJunctionPoint :: Text -- ^ mountDir - -> Text -- ^ destDir - -> IO () -createJunctionPoint mountDir destDir = - withTMN_REPARSE_DATA_BUFFER destDir $ \rdb -> - bracket (openReparseHandle mountDir) closeHandle $ \handle -> - setReparsePoint handle rdb - --- | This "Deletes" the junction point at the supplied path. On success an --- empty folder will be left in its place. -deleteJunctionPoint :: Text -> IO () -deleteJunctionPoint dir = - bracket (openReparseHandle dir) closeHandle $ \handle -> do - deleteReparsePoint handle - --- | Discover the target of a junction point at the supplied path. An --- exception will be raised if the target is either invalid or not a junction --- point. The returned path will be prefixed by \"\\??\\\". -getJunctionPointInfo :: Text -> IO Text -getJunctionPointInfo dir = - bracket (openReparseHandle dir) closeHandle $ \handle -> - with (0 :: DWORD) $ \bytesReturned -> - withTMN_REPARSE_DATA_BUFFER (T.pack "") $ \pRdb -> do - deviceIoControl handle fSCTL_GET_REPARSE_POINT Nothing 0 - (Just $ castPtr pRdb) - (fromIntegral mAXIMUM_REPARSE_DATA_BUFFER_SIZE) - (Just bytesReturned) Nothing - --not sure how to call IsReparseTagValid. - rdb <- peek pRdb - fromPtr0 $ (_pathBuffer rdb) - --- NTFS junction points are implemented as reparse points. Reparse points are --- extra tagged information attached to filesystem objects. It is up to --- application software such as the Windows Shell to detect the presence of --- reparse points and act approprietly. --- --- There are many types of reparse points. For the internal purposes of --- this library I am pretending that junction points are the only kind of --- reparse point. -setReparsePoint :: HANDLE -> Ptr TMN_REPARSE_DATA_BUFFER -> IO () -setReparsePoint handle pRdb = - -- we don't care about bytesReturned - with (0 :: DWORD) $ \bytesReturned -> do - rdb <- peek pRdb - deviceIoControl handle fSCTL_SET_REPARSE_POINT - (Just $ castPtr pRdb) - (tMN_REPARSE_DATA_BUFFER_HEADER_SIZE + - (fromIntegral $ _reparseDataLength rdb)) - Nothing 0 (Just bytesReturned) Nothing - --- 'deleteReparsePoint' will remove a reparse point pointed to by the --- argument. An exception will be raised if the argument does not point to an --- open reparse point, or possibly if the user does not have write attribute --- permissions to the object. -deleteReparsePoint :: HANDLE -> IO () -deleteReparsePoint handle = - -- When deleting reparse points the destination does not matter. - -- msdn docs refer to REPARSE_GUID_DATA_BUFFER for this instead. - withREPARSE_GUID_DATA_BUFFER [] $ \pRgdb -> - with (0 :: DWORD) $ \bytesReturned -> do - deviceIoControl handle fSCTL_DELETE_REPARSE_POINT - (Just $ castPtr pRgdb) - tMN_REPARSE_DATA_BUFFER_HEADER_SIZE - Nothing 0 (Just bytesReturned) Nothing - --- Open a reparse point attached to the supplied folder. An exception will be --- raised if the target does not exist, the user does not have read --- permissions to it, or the target does not have a reparse point attached. -openReparseHandle :: Text -> IO HANDLE -openReparseHandle path = createFile path (gENERIC_READ .|. gENERIC_WRITE) - fILE_SHARE_NONE Nothing oPEN_EXISTING - (fILE_FLAG_BACKUP_SEMANTICS .|. fILE_FLAG_OPEN_REPARSE_POINT) - Nothing - --- Low-level filesystem manipulation function. Check documentation in the MSDN --- library. -deviceIoControl :: HANDLE -> DWORD -> Maybe LPVOID -> DWORD -> Maybe LPVOID - -> DWORD -> Maybe LPDWORD -> Maybe LPOVERLAPPED -> IO () -deviceIoControl hDevice dwIoControlCode lpInBuffer nInBufferSize - lpOutBuffer nOutBufferSize lpBytesReturned lpOverlapped = - failIfFalse_ (unwords [ "DeviceIoControl", show hDevice - , show dwIoControlCode]) $ - c_DeviceIoControl hDevice dwIoControlCode - (maybe nullPtr id lpInBuffer) nInBufferSize - (maybe nullPtr id lpOutBuffer) nOutBufferSize - (maybe nullPtr id lpBytesReturned) - (maybe nullPtr id lpOverlapped) - -foreign import stdcall unsafe "windows.h DeviceIoControl" - c_DeviceIoControl :: HANDLE -> DWORD -> LPVOID -> DWORD -> LPVOID - -> DWORD -> LPDWORD -> LPOVERLAPPED -> IO Bool - -createFile :: Text -> AccessMode -> ShareMode -> Maybe LPSECURITY_ATTRIBUTES - -> CreateMode -> FileAttributeOrFlag -> Maybe HANDLE -> IO HANDLE -createFile name access share mb_attr mode flag mb_h = - -- simply converting Text to a name does not add a null character - useAsPtr0 name $ \ c_name -> - failIf (==iNVALID_HANDLE_VALUE) (unwords ["CreateFile", show name]) $ - c_CreateFile c_name access share (maybePtr mb_attr) mode flag (maybePtr mb_h) - --- | useAsPtr returns a length and byte buffer, but all the win32 functions --- rely on null termination. -useAsPtr0 :: Text -> (Ptr CWchar -> IO a) -> IO a -useAsPtr0 t f = useAsPtr (T.snoc t (chr 0x0)) $ \ str _ -> f (castPtr str) - --- This traverses the string twice. Is there a faster way? -fromPtr0 :: Ptr CWchar -> IO Text -fromPtr0 ptr = do - -- length in 16-bit words. - len <- lengthArray0 0x0000 ptr' - -- no loss of precision here. I16 is a newtype wrapper around Int. - fromPtr ptr' $ fromIntegral len - where - ptr' :: Ptr Word16 - ptr' = castPtr ptr +{-# LANGUAGE CPP #-} + +module System.Win32.JunctionPoint + ( createJunctionPoint + , deleteJunctionPoint + , getJunctionPointInfo + ) where + +import Control.Exception (bracket) +import Data.Bits +import Data.Char (chr) +import Data.Text (Text) +import qualified Data.Text as T +import Data.Text.Foreign +import Foreign +import Foreign.C +import System.Win32 hiding (createFile) + +-- Macro taken from winioctl.h +-- #define CTL_CODE( DeviceType, Function, Method, Access) ( \ +-- (DWORD) ((DeviceType) << 16 | ((Access) << 14) | ((Function) << 2) \ +-- | (Method)) +cTL_CODE :: DWORD -> DWORD -> DWORD -> DWORD -> DWORD +cTL_CODE d f m a = d `shift` 16 .|. a `shift` 14 .|. f `shift` 2 .|. m + +-- taken from winioctl.h +fILE_DEVICE_FILE_SYSTEM :: DWORD +fILE_DEVICE_FILE_SYSTEM = 0x00000009 + +-- taken from winioctl.h +mETHOD_BUFFERED :: DWORD +mETHOD_BUFFERED = 0 + +-- taken from winioctl.h +fILE_ANY_ACCESS, fILE_SPECIAL_ACCESS :: DWORD +fILE_ANY_ACCESS = 0 +fILE_SPECIAL_ACCESS = 0 + +-- taken from winioctl.h +fSCTL_SET_REPARSE_POINT :: DWORD +fSCTL_SET_REPARSE_POINT = cTL_CODE fILE_DEVICE_FILE_SYSTEM 41 + mETHOD_BUFFERED fILE_SPECIAL_ACCESS +fSCTL_GET_REPARSE_POINT :: DWORD +fSCTL_GET_REPARSE_POINT = cTL_CODE fILE_DEVICE_FILE_SYSTEM 42 + mETHOD_BUFFERED fILE_ANY_ACCESS +fSCTL_DELETE_REPARSE_POINT :: DWORD +fSCTL_DELETE_REPARSE_POINT = cTL_CODE fILE_DEVICE_FILE_SYSTEM 43 + mETHOD_BUFFERED fILE_SPECIAL_ACCESS + +iO_REPARSE_TAG_MOUNT_POINT :: DWORD +iO_REPARSE_TAG_MOUNT_POINT = 0xA0000003 + +--taken from MSDN's OpenFileById documentation +fILE_FLAG_OPEN_REPARSE_POINT :: DWORD +fILE_FLAG_OPEN_REPARSE_POINT = 0x00200000 + +mAXIMUM_REPARSE_DATA_BUFFER_SIZE :: Int +mAXIMUM_REPARSE_DATA_BUFFER_SIZE = 16 * 1024 + +-- The first 3 fields of TMN_REPARSE_DATA_BUFFER are considered the +-- header. This is used in setReparsePoint. +tMN_REPARSE_DATA_BUFFER_HEADER_SIZE :: DWORD +tMN_REPARSE_DATA_BUFFER_HEADER_SIZE = 8 + +-- I've seen this defined as FIELD_OFFSET(REPARSE_GUID_DATA_BUFFER, GenericReparseBuffer) +-- All the struct members up to the genericreparsebuffer add up to 24. I'm guessing that +-- the size-1 byte array does not add to this count. +rEPARSE_GUID_DATA_BUFFER_HEADER_SIZE :: DWORD +rEPARSE_GUID_DATA_BUFFER_HEADER_SIZE = 24 + +-- C structure. This is not documented in current versions of the +-- Windows SDK. + +-- struct TMN_REPARSE_DATA_BUFFER +-- { +-- DWORD ReparseTag; +-- WORD ReparseDataLength; +-- WORD Reserved; +-- WORD SubstituteNameOffset; +-- WORD SubstituteNameLength; +-- WORD PrintNameOffset; +-- WORD PrintNameLength; +-- WCHAR PathBuffer[1]; +-- }; + +data TMN_REPARSE_DATA_BUFFER = TMN_REPARSE_DATA_BUFFER + { _reparseTag :: !DWORD + -- Bytes in addition to first 8. This will be 12 + length of _pathBuffer + , _reparseDataLength :: !WORD + , _reserved :: !WORD + , _substituteNameOffset :: !WORD + , _substituteNameLength :: !WORD + , _printNameOffset :: !WORD + , _printNameLength :: !WORD + -- The C struct indicates a single-element array. + -- Actually, we need to allocate enough memory to + -- hold a string here. + , _pathBuffer :: !(Ptr CWchar) + } + +instance Storable TMN_REPARSE_DATA_BUFFER where + -- Storable does not allow the pokes of different sizes, so we're just + -- allocating the maximum size Microsoft documents. + sizeOf _ = mAXIMUM_REPARSE_DATA_BUFFER_SIZE + alignment _ = 1 -- no alignment? I don't know what this means. + peek ptr = do + reparseTag <- peek . castPtr $ ptr + reparseDataLength <- castPtr ptr `peekByteOff` 4 + reserved <- castPtr ptr `peekByteOff` 6 + substituteNameOffset <- castPtr ptr `peekByteOff` 8 + substituteNameLength <- castPtr ptr `peekByteOff` 10 + printNameOffset <- castPtr ptr `peekByteOff` 12 + printNameLength <- castPtr ptr `peekByteOff` 14 + let pathBuffer = castPtr ptr `plusPtr` 16 + return $ TMN_REPARSE_DATA_BUFFER reparseTag reparseDataLength reserved + substituteNameOffset substituteNameLength printNameOffset + printNameLength pathBuffer + poke ptr rdb = do + castPtr ptr `poke` _reparseTag rdb + castPtr ptr `pokeByteOff` 4 $ _reparseDataLength rdb + castPtr ptr `pokeByteOff` 6 $ _reserved rdb + castPtr ptr `pokeByteOff` 8 $ _substituteNameOffset rdb + castPtr ptr `pokeByteOff` 10 $ _substituteNameLength rdb + castPtr ptr `pokeByteOff` 12 $ _printNameOffset rdb + castPtr ptr `pokeByteOff` 14 $ _printNameLength rdb + strLen <- lengthArray0 0 $ _pathBuffer rdb + copyArray (ptr `plusPtr` 16) (_pathBuffer rdb) (strLen + 1) + +-- This data structure is almost identical to TMN_REPARSE_DATA_BUFFER, but the +-- meaning of fields differ. Microsoft documents this structure. It is +-- used for querying existing reparse points. +data REPARSE_GUID_DATA_BUFFER = REPARSE_GUID_DATA_BUFFER + { _rgdb_ReparseTag :: DWORD + -- MS specifies an odd structure, but a GUID is really just a 128-bit + -- value. + , _rgdb_GUID1 :: !DWORD + , _rgdb_GUID2 :: !DWORD + , _rgdb_GUID3 :: !DWORD + , _rgdb_GUID4 :: !DWORD + -- The C struct indicates a single-element array. + -- Actually, we need to allocate enough memory to + -- hold a string here. + , _rgdb_DataBuffer :: [BYTE] + } + +peekREPARSE_GUID_DATA_BUFFER :: Ptr REPARSE_GUID_DATA_BUFFER -> IO REPARSE_GUID_DATA_BUFFER +peekREPARSE_GUID_DATA_BUFFER ptr = do + _rgdb_ReparseTag <- peek . castPtr $ ptr + dataLength <- (castPtr ptr :: Ptr WORD) `peekByteOff` 4 + -- reserved WORD at byte 6 + _rgdb_GUID1 <- castPtr ptr `peekByteOff` 8 + _rgdb_GUID2 <- castPtr ptr `peekByteOff` 12 + _rgdb_GUID3 <- castPtr ptr `peekByteOff` 16 + _rgdb_GUID4 <- castPtr ptr `peekByteOff` 20 + dataBuffer <- peekArray dataLength (castPtr ptr `plusPtr` 24) + return $ REPARSE_GUID_DATA_BUFFER _rgdb_ReparseTag + _rgdb_GUID1 _rgdb_GUID2 _rgdb_GUID3 _rgdb_GUID4 dataBuffer + +pokeREPARSE_GUID_DATA_BUFFER :: Ptr REPARSE_GUID_DATA_BUFFER -> REPARSE_GUID_DATA_BUFFER -> IO () +pokeREPARSE_GUID_DATA_BUFFER ptr rdb = do + castPtr ptr `poke` _rgdb_ReparseTag rdb + castPtr ptr `pokeByteOff` 4 $ (fromIntegral dataLength :: WORD) + castPtr ptr `pokeByteOff` 8 $ _rgdb_GUID1 rdb + castPtr ptr `pokeByteOff` 12 $ _rgdb_GUID2 rdb + castPtr ptr `pokeByteOff` 16 $ _rgdb_GUID3 rdb + castPtr ptr `pokeByteOff` 20 $ _rgdb_GUID4 rdb + pokeArray (castPtr ptr `plusPtr` 24) $ _rgdb_DataBuffer rdb + where + dataLength = length $ _rgdb_DataBuffer rdb + +withTMN_REPARSE_DATA_BUFFER :: Text + -> (Ptr TMN_REPARSE_DATA_BUFFER -> IO a) -> IO a +withTMN_REPARSE_DATA_BUFFER dst f = + useAsPtr0 dst $ \c_dst -> + with (TMN_REPARSE_DATA_BUFFER + { _reparseTag = iO_REPARSE_TAG_MOUNT_POINT + , _reparseDataLength = dstLen + 12 + , _reserved = 0 + , _substituteNameOffset = 0 + , _substituteNameLength = dstLen + , _printNameOffset = dstLen + 2 + , _printNameLength = 0 + , _pathBuffer = c_dst + }) f + where + dstLen = fromIntegral (T.length dst) * 2 + +withREPARSE_GUID_DATA_BUFFER :: [BYTE] + -> (Ptr REPARSE_GUID_DATA_BUFFER -> IO a) -> IO a +withREPARSE_GUID_DATA_BUFFER bx f = + allocaBytes (fromIntegral rEPARSE_GUID_DATA_BUFFER_HEADER_SIZE + length bx) $ \prgdb -> do + pokeREPARSE_GUID_DATA_BUFFER prgdb + $ REPARSE_GUID_DATA_BUFFER + { _rgdb_ReparseTag = iO_REPARSE_TAG_MOUNT_POINT + , _rgdb_GUID1 = 0 + , _rgdb_GUID2 = 0 + , _rgdb_GUID3 = 0 + , _rgdb_GUID4 = 0 + -- must be empty when deleting a junction point + , _rgdb_DataBuffer = bx + } + f prgdb + +-- | Create a junction point between two folders on the same filesystem. +-- +-- 'mountDir' should be the full file path to an empty folder. This +-- folder should be on a local filesystem. +-- +-- 'destDir' should be the full file path to the junction point's target. The +-- target must be a folder on the same filesystem as its source. The path +-- should also be preceeded by \"\\??\\\". This indicates to Windows not to try +-- validating the path before using it. +-- +-- >>> createJunctionPoint "c:\\Windows\\System32" "\\??\\c:\\System32" +createJunctionPoint :: Text -- ^ mountDir + -> Text -- ^ destDir + -> IO () +createJunctionPoint mountDir destDir = + withTMN_REPARSE_DATA_BUFFER destDir $ \rdb -> + bracket (openReparseHandle mountDir) closeHandle $ \handle -> + setReparsePoint handle rdb + +-- | This "Deletes" the junction point at the supplied path. On success an +-- empty folder will be left in its place. +deleteJunctionPoint :: Text -> IO () +deleteJunctionPoint dir = + bracket (openReparseHandle dir) closeHandle $ \handle -> do + deleteReparsePoint handle + +-- | Discover the target of a junction point at the supplied path. An +-- exception will be raised if the target is either invalid or not a junction +-- point. The returned path will be prefixed by \"\\??\\\". +getJunctionPointInfo :: Text -> IO Text +getJunctionPointInfo dir = + bracket (openReparseHandle dir) closeHandle $ \handle -> + with (0 :: DWORD) $ \bytesReturned -> + withTMN_REPARSE_DATA_BUFFER (T.pack "") $ \pRdb -> do + deviceIoControl handle fSCTL_GET_REPARSE_POINT Nothing 0 + (Just $ castPtr pRdb) + (fromIntegral mAXIMUM_REPARSE_DATA_BUFFER_SIZE) + (Just bytesReturned) Nothing + --not sure how to call IsReparseTagValid. + rdb <- peek pRdb + fromPtr0 $ (_pathBuffer rdb) + +-- NTFS junction points are implemented as reparse points. Reparse points are +-- extra tagged information attached to filesystem objects. It is up to +-- application software such as the Windows Shell to detect the presence of +-- reparse points and act approprietly. +-- +-- There are many types of reparse points. For the internal purposes of +-- this library I am pretending that junction points are the only kind of +-- reparse point. +setReparsePoint :: HANDLE -> Ptr TMN_REPARSE_DATA_BUFFER -> IO () +setReparsePoint handle pRdb = + -- we don't care about bytesReturned + with (0 :: DWORD) $ \bytesReturned -> do + rdb <- peek pRdb + deviceIoControl handle fSCTL_SET_REPARSE_POINT + (Just $ castPtr pRdb) + (tMN_REPARSE_DATA_BUFFER_HEADER_SIZE + + (fromIntegral $ _reparseDataLength rdb)) + Nothing 0 (Just bytesReturned) Nothing + +-- 'deleteReparsePoint' will remove a reparse point pointed to by the +-- argument. An exception will be raised if the argument does not point to an +-- open reparse point, or possibly if the user does not have write attribute +-- permissions to the object. +deleteReparsePoint :: HANDLE -> IO () +deleteReparsePoint handle = + -- When deleting reparse points the destination does not matter. + -- msdn docs refer to REPARSE_GUID_DATA_BUFFER for this instead. + withREPARSE_GUID_DATA_BUFFER [] $ \pRgdb -> + with (0 :: DWORD) $ \bytesReturned -> do + deviceIoControl handle fSCTL_DELETE_REPARSE_POINT + (Just $ castPtr pRgdb) + rEPARSE_GUID_DATA_BUFFER_HEADER_SIZE + Nothing 0 (Just bytesReturned) Nothing + +-- Open a reparse point attached to the supplied folder. An exception will be +-- raised if the target does not exist, the user does not have read +-- permissions to it, or the target does not have a reparse point attached. +openReparseHandle :: Text -> IO HANDLE +openReparseHandle path = createFile path (gENERIC_READ .|. gENERIC_WRITE) + fILE_SHARE_NONE Nothing oPEN_EXISTING + (fILE_FLAG_BACKUP_SEMANTICS .|. fILE_FLAG_OPEN_REPARSE_POINT) + Nothing + +-- Low-level filesystem manipulation function. Check documentation in the MSDN +-- library. +deviceIoControl :: HANDLE -> DWORD -> Maybe LPVOID -> DWORD -> Maybe LPVOID + -> DWORD -> Maybe LPDWORD -> Maybe LPOVERLAPPED -> IO () +deviceIoControl hDevice dwIoControlCode lpInBuffer nInBufferSize + lpOutBuffer nOutBufferSize lpBytesReturned lpOverlapped = + failIfFalse_ (unwords [ "DeviceIoControl", show hDevice + , show dwIoControlCode]) $ + c_DeviceIoControl hDevice dwIoControlCode + (maybe nullPtr id lpInBuffer) nInBufferSize + (maybe nullPtr id lpOutBuffer) nOutBufferSize + (maybe nullPtr id lpBytesReturned) + (maybe nullPtr id lpOverlapped) + +#ifdef WIN64 +foreign import "windows.h DeviceIoControl" +#else +foreign import stdcall "windows.h DeviceIoControl" +#endif + c_DeviceIoControl :: HANDLE -> DWORD -> LPVOID -> DWORD -> LPVOID + -> DWORD -> LPDWORD -> LPOVERLAPPED -> IO Bool + +createFile :: Text -> AccessMode -> ShareMode -> Maybe LPSECURITY_ATTRIBUTES + -> CreateMode -> FileAttributeOrFlag -> Maybe HANDLE -> IO HANDLE +createFile name access share mb_attr mode flag mb_h = + -- simply converting Text to a name does not add a null character + useAsPtr0 name $ \ c_name -> + failIf (==iNVALID_HANDLE_VALUE) (unwords ["CreateFile", show name]) $ + c_CreateFile c_name access share (maybePtr mb_attr) mode flag (maybePtr mb_h) + +-- | useAsPtr returns a length and byte buffer, but all the win32 functions +-- rely on null termination. +useAsPtr0 :: Text -> (Ptr CWchar -> IO a) -> IO a +useAsPtr0 t f = useAsPtr (T.snoc t (chr 0x0)) $ \ str _ -> f (castPtr str) + +-- This traverses the string twice. Is there a faster way? +fromPtr0 :: Ptr CWchar -> IO Text +fromPtr0 ptr = do + -- length in 16-bit words. + len <- lengthArray0 0x0000 ptr' + -- no loss of precision here. I16 is a newtype wrapper around Int. + fromPtr ptr' $ fromIntegral len + where + ptr' :: Ptr Word16 + ptr' = castPtr ptr diff --git a/Win32-junction-point.cabal b/Win32-junction-point.cabal --- a/Win32-junction-point.cabal +++ b/Win32-junction-point.cabal @@ -1,52 +1,70 @@ -Name: Win32-junction-point -Version: 0.0.1 -Synopsis: Support for manipulating NTFS junction points. -Description: - This package provides the ability to manipulate NTFS junction points as - supported by Windows 2000 and above. Junction points, along with NTFS hard - links and NTFS symbolic links, are a type of symbolic link that can be made - between folders existing on the same filesystem. Please read Microsoft - KB205524 [1] for more information on junction points. - . - Junction points have always been left undocumented in the Win32 SDK. The - Windows 2000 Resource Kit came with a command-line utility named linkd.exe - to work with them. Later, Mark Russinovich of SysInternals distributed a - replacement utility named Junction [2] which accomplished the same thing. - . - This source code is based on an article [3] and C++ library [4] written by - Mike Nordell at codeproject.com. - . - It is against Microsoft's recommendation to make use of undocumented API - features. Use this library at your own risk. - . - (1) - . - (2) - . - (3) - . - (4) -License: BSD3 -License-file: LICENSE -Author: Michael Steele -Maintainer: mikesteele81@gmail.com -Copyright: Copyright (c) 2011, Michael Steele. Copyright (c) 2000, Mikael Nordell -Category: System -Build-type: Simple -Cabal-version: >=1.2 -Homepage: http://github.com/mikesteele81/Win32-junction-point -Stability: experimental - -Library - Exposed-modules: System.Win32.JunctionPoint - - Build-depends: base >= 4.0 && < 4.4 - , text >= 0.11 && < 0.12 - , Win32 >= 2.2 && < 2.3 - - -- Modules not exported by this package. - -- Other-modules: - - -- Extra tools (e.g. alex, hsc2hs, ...) needed to build the source. - -- Build-tools: - Ghc-Options: -funbox-strict-fields -Wall +Name: Win32-junction-point +Version: 0.1 +Synopsis: Support for manipulating NTFS junction points. +Description: + This package provides the ability to manipulate NTFS junction points as + supported by Windows 2000 and above. Junction points, along with NTFS hard + links and NTFS symbolic links, are a type of symbolic link that can be made + between folders existing on the same filesystem. Please read Microsoft + KB205524 [1] for more information on junction points. + . + Junction points have always been left undocumented in the Win32 SDK. The + Windows 2000 Resource Kit came with a command-line utility named linkd.exe + to work with them. Later, Mark Russinovich of SysInternals distributed a + replacement utility named Junction [2] which accomplished the same thing. + . + This source code is based on an article [3] and C++ library [4] written by + Mike Nordell at codeproject.com. + . + It is against Microsoft's recommendation to make use of undocumented API + features. Use this library at your own risk. + . + Release Notes: + . + Changes in 0.1 + . + * 64-bit GHC is now supported. + . + * Update cabal file to build on recent versions of GHC. + . + * An internal foreign import is now being called with the "safe" option. + . + * bug fixes. The deleteJunctionPoint function was failing to delete junction + points in many cases. + . + (1) + . + (2) + . + (3) + . + (4) +License: BSD3 +License-file: LICENSE +Author: Michael Steele +Maintainer: mikesteele81@gmail.com +Copyright: Copyright (c) 2011-2013, Michael Steele. Copyright (c) 2000, Mikael Nordell +Category: System +Build-type: Simple +Cabal-version: >=1.14 +Homepage: http://github.com/mikesteele81/Win32-junction-point +bug-reports: http://github.com/mikesteele81/win32-junction-point/issues + +Stability: experimental +tested-with: GHC==7.4.2, GHC==7.6.2 + +source-repository head + type: git + location: git://github.com/mikesteele81/win32-junction-point.git + +Library + default-language: Haskell2010 + Exposed-modules: System.Win32.JunctionPoint + + Build-depends: base >= 4.0 && < 5 + , text + , Win32 + ghc-options: -funbox-strict-fields -Wall + if arch(x86_64) + cpp-options: -DWIN64 +