zlib: Add test case for inflateGetDictionary

1 files changed, 25 insertions, 1 deletions

diff --git a/lib/kernel/test/zlib_SUITE.erl b/lib/kernel/test/zlib_SUITE.erl
index f8257bd20c..4720a7f5ea 100644
--- a/lib/kernel/test/zlib_SUITE.erl
+++ b/lib/kernel/test/zlib_SUITE.erl
@@ -83,7 +83,7 @@ groups() ->
       [api_open_close, api_deflateInit,
        api_deflateSetDictionary, api_deflateReset,
        api_deflateParams, api_deflate, api_deflateEnd,
-       api_inflateInit, api_inflateSetDictionary,
+       api_inflateInit, api_inflateSetDictionary, api_inflateGetDictionary,
        api_inflateSync, api_inflateReset, api_inflate, api_inflateChunk,
        api_inflateEnd, api_setBufsz, api_getBufsz, api_crc32,
        api_adler32, api_getQSize, api_un_compress, api_un_zip,
@@ -288,6 +288,30 @@ api_inflateSetDictionary(Config) when is_list(Config) ->
     ?m({'EXIT',{stream_error,_}}, zlib:inflateSetDictionary(Z1,Dict)),
     ?m(ok, zlib:close(Z1)).
 
+%% Test inflateGetDictionary.
+api_inflateGetDictionary(Config) when is_list(Config) ->
+    % Compress payload using custom dictionary
+    Z1 = zlib:open(),
+    ?m(ok, zlib:deflateInit(Z1)),
+    Dict = <<"foobar barfoo foo bar far boo">>,
+    ?m(_, zlib:deflateSetDictionary(Z1, Dict)),
+    Payload = <<"foobarbarbar">>,
+    Compressed = zlib:deflate(Z1, Payload, finish),
+    ?m(ok, zlib:close(Z1)),
+
+    % Decompress and test dictionary extraction
+    Z2 = zlib:open(),
+    ?m(ok, zlib:inflateInit(Z2)),
+    ?m(<<>>, iolist_to_binary(zlib:inflateGetDictionary(Z2))),
+    ?m({'EXIT',{stream_error,_}}, zlib:inflateSetDictionary(Z2, Dict)),
+    ?m({'EXIT',{{need_dictionary,_},_}}, zlib:inflate(Z2, Compressed)),
+    ?m(ok, zlib:inflateSetDictionary(Z2, Dict)),
+    ?m(Dict, iolist_to_binary(zlib:inflateGetDictionary(Z2))),
+    ?m(Payload, iolist_to_binary(zlib:inflate(Z2, Compressed))),
+    ?m(ok, zlib:close(Z2)),
+    ?m(?BARG, zlib:inflateSetDictionary(Z2, Dict)),
+    ok.
+
 %% Test inflateSync.
 api_inflateSync(Config) when is_list(Config) ->
     {skip,"inflateSync/1 sucks"}.