From 35de7a33009ff0f6e305e359305709cb2af7fca2 Mon Sep 17 00:00:00 2001
From: Kresten Krab Thorup <krab@trifork.com>
Date: Wed, 26 Sep 2012 16:05:51 +0200
Subject: [PATCH] Enable lz4 compression

---
 rebar.config         |  2 +-
 src/hanoidb.erl      |  2 +-
 src/hanoidb_util.erl | 22 +++++++++++-----------
 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/rebar.config b/rebar.config
index 09bc631..859c738 100644
--- a/rebar.config
+++ b/rebar.config
@@ -30,7 +30,7 @@
        , {plain_fsm, "1.1.*", {git, "git://github.com/gburd/plain_fsm", {branch, "master"}}}
        , {basho_bench, ".*", {git, "git://github.com/basho/basho_bench", {branch, "master"}}}
        , {triq, ".*", {git, "git://github.com/krestenkrab/triq", {branch, "master"}}}
-%        , {lz4, ".*", {git, "git://github.com/gburd/erlang-lz4.git", {branch, "master"}}}
+       , {lz4, ".*", {git, "git://github.com/krestenkrab/erlang-lz4.git", {branch, "master"}}}
 %        , {edown, "0.3.*", {git, "git://github.com/esl/edown.git", {branch, "master"}}}
 %        , {asciiedoc, "0.1.*", {git, "git://github.com/norton/asciiedoc.git", {branch, "master"}}}
 %        , {triq, ".*", {git, "git://github.com/krestenkrab/triq.git", {branch, "master"}}}
diff --git a/src/hanoidb.erl b/src/hanoidb.erl
index 7e847d8..6666887 100644
--- a/src/hanoidb.erl
+++ b/src/hanoidb.erl
@@ -62,7 +62,7 @@
 
 -type hanoidb() :: pid().
 -type key_range() :: #key_range{}.
--type config_option() :: {compress, none | gzip | snappy} %lz4
+-type config_option() :: {compress, none | gzip | snappy | lz4}
                        | {page_size, pos_integer()}
                        | {read_buffer_size, pos_integer()}
                        | {write_buffer_size, pos_integer()}
diff --git a/src/hanoidb_util.erl b/src/hanoidb_util.erl
index 861b673..47c7a9a 100644
--- a/src/hanoidb_util.erl
+++ b/src/hanoidb_util.erl
@@ -89,7 +89,7 @@ estimate_node_size_increment(_KVList, Key, Value)
 -define(NO_COMPRESSION, 0).
 -define(SNAPPY_COMPRESSION, 1).
 -define(GZIP_COMPRESSION, 2).
-%%-define(LZ4_COMPRESSION, 3).
+-define(LZ4_COMPRESSION, 3).
 
 use_compressed(UncompressedSize, CompressedSize) when CompressedSize < UncompressedSize ->
     true;
@@ -104,14 +104,14 @@ compress(snappy, Bin) ->
         false ->
             {?NO_COMPRESSION, Bin}
     end;
-%% compress(lz4, Bin) ->
-%%     {ok, CompressedBin} = lz4:compress(Bin),
-%%     case use_compressed(erlang:iolist_size(Bin), erlang:iolist_size(CompressedBin)) of
-%%         true ->
-%%             {?LZ4_COMPRESSION, CompressedBin};
-%%         false ->
-%%             {?NO_COMPRESSION, Bin}
-%%     end;
+compress(lz4, Bin) ->
+    {ok, CompressedBin} = lz4:compress(erlang:iolist_to_binary(Bin)),
+    case use_compressed(erlang:iolist_size(Bin), erlang:iolist_size(CompressedBin)) of
+        true ->
+            {?LZ4_COMPRESSION, CompressedBin};
+        false ->
+            {?NO_COMPRESSION, Bin}
+    end;
 compress(gzip, Bin) ->
     CompressedBin = zlib:gzip(Bin),
     case use_compressed(erlang:iolist_size(Bin), erlang:iolist_size(CompressedBin)) of
@@ -128,8 +128,8 @@ uncompress(<<?NO_COMPRESSION, Data/binary>>) ->
 uncompress(<<?SNAPPY_COMPRESSION, Data/binary>>) ->
     {ok, UncompressedData} = snappy:decompress(Data),
     UncompressedData;
-%%uncompress(<<?LZ4_COMPRESSION, Data/binary>>) ->
-%%    lz4:uncompress(Data);
+uncompress(<<?LZ4_COMPRESSION, Data/binary>>) ->
+    lz4:uncompress(Data);
 uncompress(<<?GZIP_COMPRESSION, Data/binary>>) ->
     zlib:gunzip(Data).