Merge pull request #129 from basho/adt-unicode-fix

Support writing unicode to files, thanks @jacktang

src/lager_crash_log.erl

@@ -207,7 +207,7 @@ do_log({log, Event}, #state{name=Name, fd=FD, inode=Inode, flap=Flap,
                     Time = [Date, " ", TS," =", ReportStr, "====\n"],
                     NodeSuffix = other_node_suffix(Pid),
                     Msg = io_lib:format("~s~s~s", [Time, MsgStr, NodeSuffix]),
-                    case file:write(NewFD, Msg) of
+                    case file:write(NewFD, unicode:characters_to_binary(Msg)) of
                         {error, Reason} when Flap == false ->
                             ?INT_LOG(error, "Failed to write log message to file ~s: ~s",
                                 [Name, file:format_error(Reason)]),

src/lager_file_backend.erl

@@ -210,7 +210,7 @@ write(#state{name=Name, fd=FD, inode=Inode, flap=Flap, size=RotSize,
 
 do_write(#state{fd=FD, name=Name, flap=Flap} = State, Level, Msg) ->
     %% delayed_write doesn't report errors
-    _ = file:write(FD, Msg),
+    _ = file:write(FD, unicode:characters_to_binary(Msg)),
     {mask, SyncLevel} = State#state.sync_on,
     case (Level band SyncLevel) /= 0 of
         true ->
@@ -476,6 +476,26 @@ filesystem_test_() ->
                         ?assertMatch([_, _, "[error]", Pid, "Test message\n"], re:split(Bin, " ", [{return, list}, {parts, 5}]))
                 end
             },
+            {"don't choke on unicode",
+                fun() ->
+                        gen_event:add_handler(lager_event, lager_file_backend, [{"test.log", info}, {lager_default_formatter}]),
+                        lager:log(error, self(),"~ts", [[20013,25991,27979,35797]]),
+                        {ok, Bin} = file:read_file("test.log"),
+                        Pid = pid_to_list(self()),
+                        ?assertMatch([_, _, "[error]", Pid,  [228,184,173,230,150,135,230,181,139,232,175,149, $\n]], re:split(Bin, " ", [{return, list}, {parts, 5}]))
+                end
+            },
+            {"don't choke on latin-1",
+                fun() ->
+                        %% XXX if this test fails, check that this file is encoded latin-1, not utf-8!
+                        gen_event:add_handler(lager_event, lager_file_backend, [{"test.log", info}, {lager_default_formatter}]),
+                        lager:log(error, self(),"~ts", ["LÆÝÎN-ï"]),
+                        {ok, Bin} = file:read_file("test.log"),
+                        Pid = pid_to_list(self()),
+                        Res = re:split(Bin, " ", [{return, list}, {parts, 5}]),
+                        ?assertMatch([_, _, "[error]", Pid,  [76,195,134,195,157,195,142,78,45,195,175,$\n]], Res)
+                end
+            },
             {"file can't be opened on startup triggers an error message",
                 fun() ->
                         {ok, FInfo} = file:read_file_info("test.log"),