diff --git a/csrc/sendfile_linux.c b/csrc/sendfile_linux.c --- a/csrc/sendfile_linux.c +++ b/csrc/sendfile_linux.c @@ -6,21 +6,17 @@ #include #include -/* return value is system error code */ -int c_sendfile_linux(int out_fd, char* in_fp) { - int in_fd; - struct stat in_stat; - - in_fd = open(in_fp, O_RDONLY); +/* return value is an errno code or 0 if there is no error */ +int c_sendfile_linux(const int out_fd, const char* in_fp, const long _offset, const long _count) { + off_t offset = _offset; + size_t count = _count; + int in_fd = open(in_fp, O_RDONLY); + if(in_fd == -1) { return errno; } - - if(fstat(in_fd, &in_stat) == -1) { - return errno; - } - - if(sendfile(out_fd, in_fd, NULL, in_stat.st_size) == -1) { + + if(sendfile(out_fd, in_fd, &offset, count) == -1) { return errno; } @@ -28,7 +24,6 @@ return errno; } - /* if no errors, return 0 to indicate no errors */ + /* return 0 to indicate no errors */ return 0; } - diff --git a/csrc/sendfile_win32.c b/csrc/sendfile_win32.c --- a/csrc/sendfile_win32.c +++ b/csrc/sendfile_win32.c @@ -3,25 +3,31 @@ #include #include -/* return value is system error code defined here: +/* return value is 0 if there is no error otherwise it is a system error code defined here: * http://msdn.microsoft.com/en-us/library/ms681381(VS.85).aspx */ -int c_sendfile_win32(int out_fd, char* in_fp) { - HANDLE in_hdl = - CreateFile( - in_fp, - GENERIC_READ, - FILE_SHARE_READ, - NULL, - OPEN_EXISTING, - FILE_FLAG_SEQUENTIAL_SCAN, - NULL - ); +int c_sendfile_win32(const int out_fd, const char* in_fp, const long _offset, const long _count) { + LONG offset = _offset; + DWORD count = _count; + HANDLE in_hdl = CreateFile( + in_fp, + GENERIC_READ, + FILE_SHARE_READ, + NULL, + OPEN_EXISTING, + FILE_FLAG_SEQUENTIAL_SCAN, + NULL + ); + if(in_hdl == INVALID_HANDLE_VALUE) { return GetLastError(); } - if(! TransmitFile(out_fd, in_hdl, 0, 0, NULL, NULL, TF_USE_KERNEL_APC)) { + if(SetFilePointer(in_hdl, offset, NULL, FILE_BEGIN) == INVALID_SET_FILE_POINTER) { + return GetLastError(); + } + + if(! TransmitFile(out_fd, in_hdl, count, 0, NULL, NULL, TF_USE_KERNEL_APC)) { return WSAGetLastError(); } @@ -29,6 +35,6 @@ return GetLastError(); } - /* if no errors, return 0 to indicate no errors */ + /* return 0 to indicate no errors */ return 0; } diff --git a/sendfile.cabal b/sendfile.cabal --- a/sendfile.cabal +++ b/sendfile.cabal @@ -1,8 +1,14 @@ name: sendfile -version: 0.1 +version: 0.2 stability: experimental synopsis: A portable sendfile library description: A library which exposes zero-copy sendfile functionality in a portable way. If a platform does not support sendfile, a fallback implementation in haskell is provided. + . + Currently supported platforms: + * Windows 2000+ (Native) + * Linux 2.6+ (Native) + * Everything else (Haskell) + license: BSD3 license-file: LICENSE author: Matthew Elder @@ -20,27 +26,24 @@ hs-source-dirs: src exposed-modules: SendFile - SendFile.Internal + + other-modules: SendFile.Internal build-depends: base >= 3 && < 5, - bytestring >= 0.9.1.4 && < 0.10, network >= 2 && < 3 - if flag(portable) - cc-options: -DPORTABLE_SENDFILE + if os(windows) && !flag(portable) + cc-options: -DWIN32_SENDFILE + c-sources: csrc/sendfile_win32.c + extra-libraries: kernel32, mswsock else - if os(windows) - cc-options: -DWIN32_SENDFILE - c-sources: csrc/sendfile_win32.c - extra-libraries: kernel32, mswsock + if os(linux) && !flag(portable) + cc-options: -DLINUX_SENDFILE + c-sources: csrc/sendfile_linux.c else - if os(linux) - cc-options: -DLINUX_SENDFILE - c-sources: csrc/sendfile_linux.c - else - cc-options: -DPORTABLE_SENDFILE + cc-options: -DPORTABLE_SENDFILE + build-depends: bytestring >= 0.9.1.4 && < 0.10 source-repository head type: darcs location: http://patch-tag.com/r/sendfile/pullrepo - diff --git a/src/SendFile.hs b/src/SendFile.hs --- a/src/SendFile.hs +++ b/src/SendFile.hs @@ -1,17 +1,33 @@ module SendFile ( + fileSize, sendFile, + sendFile', sendFileMode ) where import qualified SendFile.Internal import System.IO (Handle(..)) --- | A cross-platform wrapper for sendfile -- this implements an available operating-system call if supported, otherwise it falls back to a portable haskell implementation. It takes a Handle which it will first flush before handing it to the operating system to perform the transmission. +-- | Get the size of a file. +fileSize :: FilePath -- ^ The path of the file + -> IO Int -- ^ The size of the file (in bytes) +fileSize = SendFile.Internal.fileSize + +-- | A cross-platform wrapper for sendfile -- this implements an available operating-system call if supported, otherwise it falls back to a portable haskell implementation. It will flush the output Handle before handing it to the operating system for transmission. sendFile :: Handle -- ^ The output Handle -> FilePath -- ^ The path where the input file resides - -> IO () -- ^ Whether or not the transmission was successful + -> IO () sendFile = SendFile.Internal.sendFile --- | Returns the mode that sendfile was compiled with. Mainly for debugging use. Possible values are 'WIN32_SENDFILE' and 'PORTABLE_SENDFILE'. +-- | Like sendFile except that it additionally allows you to specify an offset and count. The behavior of reading beyond the end of the file is undefined. +sendFile' :: Handle -- ^ The output Handle + -> FilePath -- ^ The path where the input file resides + -> Int -- ^ The starting offset of the file (in bytes) + -> Int -- ^ The number of bytes to read + -> IO () +sendFile' = SendFile.Internal.sendFile' + +-- | Returns the mode that sendfile was compiled with. Mainly for debugging use. Possible values are 'WIN32_SENDFILE', 'LINUX_SENDFILE', and 'PORTABLE_SENDFILE'. sendFileMode :: String -- ^ The mode that sendfile was compiled with sendFileMode = SendFile.Internal.sendFileMode + diff --git a/src/SendFile/Internal.hsc b/src/SendFile/Internal.hsc --- a/src/SendFile/Internal.hsc +++ b/src/SendFile/Internal.hsc @@ -1,14 +1,22 @@ {-# LANGUAGE CPP, ForeignFunctionInterface #-} module SendFile.Internal ( + fileSize, sendFile, + sendFile', sendFileMode ) where - -import Data.ByteString.Char8 -import Prelude hiding (readFile) -import System.IO (Handle(..), hFlush) -#if defined(WIN32_SENDFILE) && !defined(PORTABLE_SENDFILE) +import System.IO ( + Handle(..), + IOMode(..), + SeekMode(..), + hFileSize, + hFlush, + hSeek, + withBinaryFile + ) + +#if defined(WIN32_SENDFILE) import Foreign.C import GHC.IOBase (haFD) import GHC.Handle (withHandle_) @@ -16,22 +24,23 @@ sendFileMode :: String sendFileMode = "WIN32_SENDFILE" -sendFile :: Handle -> FilePath -> IO () -sendFile outh infp = do +sendFile' :: Handle -> FilePath -> Int -> Int -> IO () +sendFile' outh infp offset count = do -- flush outh before handing it sendFile hFlush outh withHandle_ "sendFile" outh $ \outh' -> do withCString infp $ \in_fp -> do let out_fd = haFD outh' - err <- c_sendfile_win32 out_fd in_fp + err <- c_sendfile_win32 out_fd in_fp (fromIntegral offset) (fromIntegral count) if err == 0 then return () else fail ("system error " ++ show err) foreign import ccall - c_sendfile_win32 :: CInt -> CString -> IO Int -#else -# if defined(LINUX_SENDFILE) && !defined(PORTABLE_SENDFILE) + c_sendfile_win32 :: CInt -> CString -> CLong -> CLong -> IO Int +#endif + +#if defined(LINUX_SENDFILE) import Foreign.C import GHC.IOBase (haFD) import GHC.Handle (withHandle_) @@ -39,29 +48,44 @@ sendFileMode :: String sendFileMode = "LINUX_SENDFILE" -sendFile :: Handle -> FilePath -> IO () -sendFile outh infp = do +sendFile' :: Handle -> FilePath -> Int -> Int -> IO () +sendFile' outh infp offset count = do -- flush outh before handing it sendFile hFlush outh withHandle_ "sendFile" outh $ \outh' -> do withCString infp $ \in_fp -> do let out_fd = haFD outh' - err <- c_sendfile_linux out_fd in_fp + err <- c_sendfile_linux out_fd in_fp (fromIntegral offset) (fromIntegral count) if err == 0 then return () else fail ("errno " ++ show err) foreign import ccall - c_sendfile_linux :: CInt -> CString -> IO Int -# else + c_sendfile_linux :: CInt -> CString -> CLong -> CLong -> IO Int +#endif + +#if defined(PORTABLE_SENDFILE) +import Prelude hiding (readFile) +import Data.ByteString.Char8 + sendFileMode :: String sendFileMode = "PORTABLE_SENDFILE" -- FIXME: possibly immature / inefficient implementation -sendFile :: Handle -> FilePath -> IO () -sendFile outh infp = do - hPutStr outh =<< readFile infp +sendFile' :: Handle -> FilePath -> Int -> Int -> IO () +sendFile' outh infp offset count = + withBinaryFile infp ReadMode $ \inh -> do + hSeek inh AbsoluteSeek (fromIntegral offset) + hPutStr outh =<< hGet inh count + hFlush outh return () -# endif #endif + +fileSize :: FilePath -> IO Int +fileSize fp = fmap fromIntegral (withBinaryFile fp ReadMode hFileSize) + +sendFile :: Handle -> FilePath -> IO () +sendFile outh infp = do + count <- fileSize infp + sendFile' outh infp 0 count