Copyright	(c) Dong Han 2017-2018
License	BSD
Maintainer	winterland1989@gmail.com
Stability	experimental
Portability	non-portable
Safe Haskell	None
Language	Haskell2010

Std.IO.Buffered

Contents

Input & Output device
Buffered Input
Buffered Output
Exceptions
common buffer size

Description

This module provide buffered IO interface.

Synopsis

class Input i where
- readInput :: HasCallStack => i -> Ptr Word8 -> Int -> IO Int
class Output o where
- writeOutput :: HasCallStack => o -> Ptr Word8 -> Int -> IO ()
data BufferedInput i
newBufferedInput :: input -> Int -> IO (BufferedInput input)
readBuffer :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes
unReadBuffer :: (HasCallStack, Input i) => Bytes -> BufferedInput i -> IO ()
readParser :: (HasCallStack, Input i) => Parser a -> BufferedInput i -> IO (Bytes, Either ParseError a)
readExactly :: (HasCallStack, Input i) => Int -> BufferedInput i -> IO Bytes
readToMagic :: (HasCallStack, Input i) => Word8 -> BufferedInput i -> IO Bytes
readToMagic' :: (HasCallStack, Input i) => Word8 -> BufferedInput i -> IO Bytes
readLine :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes
readLine' :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes
readAll :: (HasCallStack, Input i) => BufferedInput i -> IO [Bytes]
readAll' :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes
data BufferedOutput o
newBufferedOutput :: output -> Int -> IO (BufferedOutput output)
writeBuffer :: Output o => BufferedOutput o -> Bytes -> IO ()
writeBuilder :: Output o => BufferedOutput o -> Builder a -> IO ()
flushBuffer :: Output f => BufferedOutput f -> IO ()
data ShortReadException = ShortReadException IOEInfo
defaultChunkSize :: Int
smallChunkSize :: Int

Input & Output device

class Input i where Source #

Input device

Laws: readInput should return 0 on EOF.

Note: readInput is considered not thread-safe, e.g. A Input device can only be used with a single BufferedInput, If multiple BufferedInput s are opened on a same Input device, the behaviour will be undefined.

Methods

readInput :: HasCallStack => i -> Ptr Word8 -> Int -> IO Int Source #

Instances

Input UVStream Source #
Instance details Defined in Std.IO.UV.Manager Methods readInput :: UVStream -> Ptr Word8 -> Int -> IO Int Source #
Input StdStream Source #
Instance details Defined in Std.IO.StdStream Methods readInput :: StdStream -> Ptr Word8 -> Int -> IO Int Source #
Input UVFileReader Source #
Instance details Defined in Std.IO.FileSystemT Methods readInput :: UVFileReader -> Ptr Word8 -> Int -> IO Int Source #
Input UVFile Source #
Instance details Defined in Std.IO.FileSystemT Methods readInput :: UVFile -> Ptr Word8 -> Int -> IO Int Source #
Input UVFileReader Source #
Instance details Defined in Std.IO.FileSystem Methods readInput :: UVFileReader -> Ptr Word8 -> Int -> IO Int Source #
Input UVFile Source #
Instance details Defined in Std.IO.FileSystem Methods readInput :: UVFile -> Ptr Word8 -> Int -> IO Int Source #

class Output o where Source #

Output device

Laws: writeOutput should not return until all data are written (may not necessarily flushed to hardware, that should be done in device specific way).

Methods

writeOutput :: HasCallStack => o -> Ptr Word8 -> Int -> IO () Source #

Instances

Output UVStream Source #
Instance details Defined in Std.IO.UV.Manager Methods writeOutput :: UVStream -> Ptr Word8 -> Int -> IO () Source #
Output StdStream Source #
Instance details Defined in Std.IO.StdStream Methods writeOutput :: StdStream -> Ptr Word8 -> Int -> IO () Source #
Output UVFileWriter Source #
Instance details Defined in Std.IO.FileSystemT Methods writeOutput :: UVFileWriter -> Ptr Word8 -> Int -> IO () Source #
Output UVFile Source #
Instance details Defined in Std.IO.FileSystemT Methods writeOutput :: UVFile -> Ptr Word8 -> Int -> IO () Source #
Output UVFileWriter Source #
Instance details Defined in Std.IO.FileSystem Methods writeOutput :: UVFileWriter -> Ptr Word8 -> Int -> IO () Source #
Output UVFile Source #
Instance details Defined in Std.IO.FileSystem Methods writeOutput :: UVFile -> Ptr Word8 -> Int -> IO () Source #

Buffered Input

data BufferedInput i Source #

Input device with buffer, NOT THREAD SAFE!

newBufferedInput Source #

Arguments

:: input
-> Int	Input buffer size
-> IO (BufferedInput input)

readBuffer :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes Source #

Request bytes from BufferedInput.

The buffering logic is quite simple:

If we have pushed back bytes, directly return it, otherwise we read using buffer size. If we read N bytes, and N is larger than half of the buffer size, then we freeze buffer and return, otherwise we copy buffer into result and reuse buffer afterward.

unReadBuffer :: (HasCallStack, Input i) => Bytes -> BufferedInput i -> IO () Source #

Push bytes back into buffer

readParser :: (HasCallStack, Input i) => Parser a -> BufferedInput i -> IO (Bytes, Either ParseError a) Source #

Read buffer and parse with Parser.

readExactly :: (HasCallStack, Input i) => Int -> BufferedInput i -> IO Bytes Source #

Read exactly N bytes

If EOF reached before N bytes read, a ShortReadException will be thrown

readToMagic :: (HasCallStack, Input i) => Word8 -> BufferedInput i -> IO Bytes Source #

Read until reach a magic bytes

If EOF is reached before meet a magic byte, partial bytes are returned.

readToMagic' :: (HasCallStack, Input i) => Word8 -> BufferedInput i -> IO Bytes Source #

Read until reach a magic bytes

If EOF is reached before meet a magic byte, a ShortReadException will be thrown.

readLine :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes Source #

Read to a linefeed ('\n' or '\r\n'), return Bytes before it.

If EOF is reached before meet a magic byte, partial line is returned.

readLine' :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes Source #

Read to a linefeed ('\n' or '\r\n'), return Bytes before it.

If EOF reached before meet a '\n', a ShortReadException will be thrown.

readAll :: (HasCallStack, Input i) => BufferedInput i -> IO [Bytes] Source #

Read all chunks from a BufferedInput.

readAll' :: (HasCallStack, Input i) => BufferedInput i -> IO Bytes Source #

Read all chunks from a BufferedInput, and concat chunks together.

Buffered Output

data BufferedOutput o Source #

Output device with buffer, NOT THREAD SAFE!

newBufferedOutput Source #

Arguments

:: output
-> Int	Output buffer size
-> IO (BufferedOutput output)

writeBuffer :: Output o => BufferedOutput o -> Bytes -> IO () Source #

Write Bytes into buffered handle.

Copy Bytes to buffer if it can hold, otherwise write both buffer(if not empty) and Bytes.

writeBuilder :: Output o => BufferedOutput o -> Builder a -> IO () Source #

Write Bytes into buffered handle.

Copy Bytes to buffer if it can hold, otherwise write both buffer(if not empty) and Bytes.

flushBuffer :: Output f => BufferedOutput f -> IO () Source #

Flush the buffer(if not empty).

Exceptions

data ShortReadException Source #

Constructors

ShortReadException IOEInfo

Instances

Show ShortReadException Source #
Instance details Defined in Std.IO.Buffered Methods showsPrec :: Int -> ShortReadException -> ShowS # show :: ShortReadException -> String # showList :: [ShortReadException] -> ShowS #
Exception ShortReadException Source #
Instance details Defined in Std.IO.Buffered Methods toException :: ShortReadException -> SomeException # fromException :: SomeException -> Maybe ShortReadException # displayException :: ShortReadException -> String #

common buffer size

defaultChunkSize :: Int Source #

The chunk size used for I/O. Currently set to 32k-chunkOverhead

smallChunkSize :: Int Source #

The recommended chunk size. Currently set to 4k - chunkOverhead.