| Safe Haskell | None |
|---|---|
| Language | Haskell98 |
Data.Conduit.Zlib
Description
Streaming compression and decompression using conduits.
Parts of this code were taken from zlib-enum and adapted for conduits.
Synopsis
- compress :: (PrimMonad m, MonadThrow m) => Int -> WindowBits -> ConduitT ByteString ByteString m ()
- decompress :: (PrimMonad m, MonadThrow m) => WindowBits -> ConduitT ByteString ByteString m ()
- gzip :: (MonadThrow m, PrimMonad m) => ConduitT ByteString ByteString m ()
- ungzip :: (PrimMonad m, MonadThrow m) => ConduitT ByteString ByteString m ()
- compressFlush :: (PrimMonad m, MonadThrow m) => Int -> WindowBits -> ConduitT (Flush ByteString) (Flush ByteString) m ()
- decompressFlush :: (PrimMonad m, MonadThrow m) => WindowBits -> ConduitT (Flush ByteString) (Flush ByteString) m ()
- multiple :: Monad m => ConduitT ByteString a m () -> ConduitT ByteString a m ()
- data WindowBits = WindowBits Int
- defaultWindowBits :: WindowBits
Conduits
Arguments
| :: (PrimMonad m, MonadThrow m) | |
| => Int | Compression level |
| -> WindowBits | Zlib parameter (see the zlib-bindings package as well as the zlib C library) |
| -> ConduitT ByteString ByteString m () |
Compress (deflate) a stream of ByteStrings. The WindowBits also control
the format (zlib vs. gzip).
Arguments
| :: (PrimMonad m, MonadThrow m) | |
| => WindowBits | Zlib parameter (see the zlib-bindings package as well as the zlib C library) |
| -> ConduitT ByteString ByteString m () |
Decompress (inflate) a stream of ByteStrings. For example:
sourceFile "test.z" $= decompress defaultWindowBits $$ sinkFile "test"
gzip :: (MonadThrow m, PrimMonad m) => ConduitT ByteString ByteString m () Source #
Gzip compression with default parameters.
ungzip :: (PrimMonad m, MonadThrow m) => ConduitT ByteString ByteString m () Source #
Gzip decompression with default parameters.
Flushing
Arguments
| :: (PrimMonad m, MonadThrow m) | |
| => Int | Compression level |
| -> WindowBits | Zlib parameter (see the zlib-bindings package as well as the zlib C library) |
| -> ConduitT (Flush ByteString) (Flush ByteString) m () |
Same as compress, but allows you to explicitly flush the stream.
Arguments
| :: (PrimMonad m, MonadThrow m) | |
| => WindowBits | Zlib parameter (see the zlib-bindings package as well as the zlib C library) |
| -> ConduitT (Flush ByteString) (Flush ByteString) m () |
Same as decompress, but allows you to explicitly flush the stream.
Decompression combinators
multiple :: Monad m => ConduitT ByteString a m () -> ConduitT ByteString a m () Source #
The standard decompress and ungzip functions will only decompress a
single compressed entity from the stream. This combinator will exhaust the
stream completely of all individual compressed entities. This is useful for
cases where you have a concatenated archive, e.g. cat file1.gz file2.gz >
combined.gz.
Usage:
sourceFile "combined.gz" $$ multiple ungzip =$ consume
This combinator will not fail on an empty stream. If you want to ensure that at least one compressed entity in the stream exists, consider a usage such as:
sourceFile "combined.gz" $$ (ungzip >> multiple ungzip) =$ consume
Since: 1.1.10
Re-exported from zlib-bindings
data WindowBits #
This specifies the size of the compression window. Larger values of this parameter result in better compression at the expense of higher memory usage.
The compression window size is the value of the the window bits raised to
the power 2. The window bits must be in the range 9..15 which corresponds
to compression window sizes of 512b to 32Kb. The default is 15 which is also
the maximum size.
The total amount of memory used depends on the window bits and the
MemoryLevel. See the MemoryLevel for the details.
Constructors
| WindowBits Int |
Instances
defaultWindowBits :: WindowBits #
The default WindowBits is 15 which is also the maximum size.