lz4 (empty) → 0.1.0.0

raw patch · 5 files changed

+114/−0 lines, 5 filesdep +QuickCheckdep +basedep +bytestringsetup-changed

Dependencies added: QuickCheck, base, bytestring, hspec, hspec-discover, hspec-shouldbe, lz4

Files

• LICENSE +30/−0
• Setup.hs +2/−0
• lz4.cabal +33/−0
• src/Codec/Compression/LZ4.hs +47/−0
• test/Spec.hs +2/−0

@@ -0,0 +1,30 @@+Copyright (c) 2012, Mark Wotton++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 Mark Wotton 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.

@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain

@@ -0,0 +1,33 @@+name:                lz4+version:             0.1.0.0+synopsis:            Haskell bindings to the lz4 compression library+description:         lz4 is a fast compression library, and can be found at+                     http://code.google.com/p/lz4/+                     a version that adds a C library can be found at+                     https://github.com/mwotton/lz4+homepage:            http://github.com/mwotton/lz4hs+license:             BSD3+license-file:        LICENSE+author:              Mark Wotton+maintainer:          mwotton@gmail.com++category:            Codec+build-type:          Simple+cabal-version:       >=1.8+source-repository head+  type:        git+  location:    git://github.com/mwotton/lz4hs.git++library+  exposed-modules: Codec.Compression.LZ4+  hs-source-dirs: src+  extra-libraries: lz4+  build-depends:       base ==4.5.*, bytestring++test-suite spec+  type:           exitcode-stdio-1.0+  main-is:        Spec.hs+  hs-source-dirs: test+  extra-libraries: lz4+  build-depends:  base, hspec, hspec-discover, lz4, QuickCheck, hspec-shouldbe,+                  bytestring

@@ -0,0 +1,47 @@+module Codec.Compression.LZ4 (compress, compressHC, uncompress) where+import Codec.Compression.LZ4.Foreign+import Foreign+import Data.ByteString+import Debug.Trace+import Data.ByteString.Unsafe++-- Following zlib's lead, we pretend to be pure on Bytestrings+-- errors may be thrown for bad formats. I'm not entirely comfortable with this.++-- we use unsafeUseAsCStringLen because the underlying files may be large, and+-- we trust lz4 not to tamper with the input buffer.++-- TODO: use a standard chunk size & support lazy Bytestrings+-- TODO: load files from disk: we don't currently support the full file format with+--       magic archive numbers etc.++-- compressHC = compressWorker c_LZ4_compressHC+-- compress   = compressWorker c_LZ4_compress++-- for some reason, when I factor this out in the obvious way, I get link errors. Very confusing. FIXME+compressHC x = unsafePerformIO $ unsafeUseAsCStringLen x $ \(input,len) ->+  let outLen = c_LZ4_compressBound len in+  allocaBytes (1+outLen) $ \out -> do    +    written <- c_LZ4_compressHC input out (fromIntegral len)+    if written == 0+      then error "compression failed"+      else packCStringLen (out, written) --  `doTrace` ("compress", x, len, outLen, written)++compress x = unsafePerformIO $ unsafeUseAsCStringLen x $ \(input,len) ->+  let outLen = c_LZ4_compressBound len in+  allocaBytes (1+outLen) $ \out -> do    +    written <- c_LZ4_compress input out (fromIntegral len)+    if written == 0+      then error "compression failed"+      else packCStringLen (out, written) --  `doTrace` ("compress", x, len, outLen, written)++uncompress :: ByteString -> ByteString+uncompress x = unsafePerformIO $ unsafeUseAsCStringLen x $ \(input,len) ->+  -- this is a complete punt. let's say we use 5*len for the moment,+  -- and extend to lazy bytestrings later.+  let outLen = 5 * len in+  allocaBytes (1+outLen) $ \out -> do+    written <- c_LZ4_uncompress_unknownOutputSize input out (fromIntegral len) (fromIntegral outLen)+    if written < 0+      then error "decompression failed!"+      else packCStringLen (out, written)

@@ -0,0 +1,2 @@+-- file test/Spec.hs+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}