some refactorings. Not all done yet.

1 files changed, 51 insertions, 50 deletions

diff --git a/src/rabbit_disk_queue.erl b/src/rabbit_disk_queue.erl
index 7ee02f99e8..b32fffe4d1 100644
--- a/src/rabbit_disk_queue.erl
+++ b/src/rabbit_disk_queue.erl
@@ -260,8 +260,14 @@ stop_and_obliterate() ->
 %% ---- GEN-SERVER INTERNAL API ----
 
 init([FileSizeLimit, ReadFileHandlesLimit]) ->
-    %% gen_server does not trap by default. Without this, terminate/2
-    %% won't be called
+    %% If the gen_server is part of a supervision tree and is ordered
+    %% by its supervisor to terminate, terminate will be called with
+    %% Reason=shutdown if the following conditions apply:
+    %%     * the gen_server has been set to trap exit signals, and
+    %%     * the shutdown strategy as defined in the supervisor's
+    %%       child specification is an integer timeout value, not
+    %%       brutal_kill.
+    %% Otherwise, the gen_server will be immediately terminated.
     process_flag(trap_exit, true),
     ok = filelib:ensure_dir(form_filename("nothing")),
     InitName = "0" ++ ?FILE_EXTENSION,
@@ -370,9 +376,7 @@ base_directory() ->
 
 internal_deliver(Q, State =
 		 #dqstate { msg_location = MsgLocation,
-			    sequences = Sequences,
-			    read_file_handles_limit = ReadFileHandlesLimit,
-			    read_file_handles = {ReadHdls, ReadHdlsAge}
+			    sequences = Sequences
 			   }) ->
     case ets:lookup(Sequences, Q) of
 	[] -> {ok, empty, State};
@@ -383,31 +387,7 @@ internal_deliver(Q, State =
 		 #dq_msg_loc {is_delivered = Delivered, msg_id = MsgId}] ->
 		    [{MsgId, _RefCount, File, Offset, TotalSize}] =
 			dets:lookup(MsgLocation, MsgId),
-		    Now = now(),
-		    {FileHdl, ReadHdls1, ReadHdlsAge1} =
-			case dict:find(File, ReadHdls) of
-			    error ->
-				{ok, Hdl} = file:open(form_filename(File),
-						      [read, raw, binary,
-						       read_ahead]),
-				case dict:size(ReadHdls) < ReadFileHandlesLimit of
-				    true ->
-					{Hdl, ReadHdls, ReadHdlsAge};
-				    _False ->
-					{Then, OldFile, ReadHdlsAge3} =
-					    gb_trees:take_smallest(ReadHdlsAge),
-					{ok, {OldHdl, Then}} =
-					    dict:find(OldFile, ReadHdls),
-					ok = file:close(OldHdl),
-					{Hdl, dict:erase(OldFile, ReadHdls),
-					 ReadHdlsAge3}
-				end;
-			    {ok, {Hdl, Then}} ->
-				{Hdl, ReadHdls,
-				 gb_trees:delete(Then, ReadHdlsAge)}
-			end,
-		    ReadHdls2 = dict:store(File, {FileHdl, Now}, ReadHdls1),
-		    ReadHdlsAge2 = gb_trees:enter(Now, File, ReadHdlsAge1),
+		    {FileHdl, State1} = getReadHandle(File, State),
 		    %% read the message
 		    {ok, {MsgBody, BodySize}} =
 			read_message_at_offset(FileHdl, Offset, TotalSize),
@@ -417,10 +397,38 @@ internal_deliver(Q, State =
 		    end,
 		    true = ets:insert(Sequences, {Q, ReadSeqId + 1, WriteSeqId}),
 		    {ok, {MsgId, MsgBody, BodySize, Delivered, {MsgId, ReadSeqId}},
-		     State #dqstate { read_file_handles = {ReadHdls2, ReadHdlsAge2} }}
+		     State1}
 	    end
     end.
 
+getReadHandle(File, State =
+	      #dqstate { read_file_handles = {ReadHdls, ReadHdlsAge},
+			 read_file_handles_limit = ReadFileHandlesLimit }) ->
+    Now = now(),
+    {FileHdl, ReadHdls1, ReadHdlsAge1} =
+	case dict:find(File, ReadHdls) of
+	    error ->
+		{ok, Hdl} = file:open(form_filename(File),
+				      [read, raw, binary,
+				       read_ahead]),
+		case dict:size(ReadHdls) < ReadFileHandlesLimit of
+		    true ->
+			{Hdl, ReadHdls, ReadHdlsAge};
+		    _False ->
+			{Then, OldFile, ReadHdlsAge2} =
+			    gb_trees:take_smallest(ReadHdlsAge),
+			{ok, {OldHdl, Then}} =
+			    dict:find(OldFile, ReadHdls),
+			ok = file:close(OldHdl),
+			{Hdl, dict:erase(OldFile, ReadHdls), ReadHdlsAge2}
+		end;
+	    {ok, {Hdl, Then}} ->
+		{Hdl, ReadHdls, gb_trees:delete(Then, ReadHdlsAge)}
+	end,
+    ReadHdls3 = dict:store(File, {FileHdl, Now}, ReadHdls1),
+    ReadHdlsAge3 = gb_trees:enter(Now, File, ReadHdlsAge1),
+    {FileHdl, State #dqstate {read_file_handles = {ReadHdls3, ReadHdlsAge3}}}.
+
 internal_ack(Q, MsgIds, State) ->
     remove_messages(Q, MsgIds, true, State).
 
@@ -664,6 +672,14 @@ sortMsgLocationsByOffset(Asc, List) ->
 		       Comp(OffA, OffB)
 	       end, List).
 
+truncateAndExtendFile(FileHdl, Lowpoint, Highpoint) ->
+    {ok, Lowpoint} = file:position(FileHdl, {bof, Lowpoint}),
+    ok = file:truncate(FileHdl),
+    {ok, Highpoint} = file:position(FileHdl, {bof, Highpoint}),
+    ok = file:truncate(FileHdl),
+    {ok, Lowpoint} = file:position(FileHdl, {bof, Lowpoint}),
+    ok.
+
 combineFiles({Source, SourceValid, _SourceContiguousTop,
 	      _SourceLeft, _SourceRight},
 	     {Destination, DestinationValid, DestinationContiguousTop,
@@ -683,14 +699,8 @@ combineFiles({Source, SourceValid, _SourceContiguousTop,
     %%   then truncate, copy back in, and then copy over from Source
     %% otherwise we just truncate straight away and copy over from Source
     if DestinationContiguousTop =:= DestinationValid ->
-	    {ok, DestinationValid} = file:position(DestinationHdl,
-						   {bof, DestinationValid}),
-	    ok = file:truncate(DestinationHdl),
-	    {ok, ExpectedSize}     = file:position(DestinationHdl,
-						   {cur, SourceValid}),
-	    ok = file:truncate(DestinationHdl),
-	    {ok, DestinationValid} = file:position(DestinationHdl,
-						   {bof, DestinationValid});
+	    ok = truncateAndExtendFile(DestinationHdl,
+				       DestinationValid, ExpectedSize);
        true ->
 	    Tmp = filename:rootname(Destination) ++ ?FILE_EXTENSION_TMP,
 	    {ok, TmpHdl} =
@@ -755,17 +765,8 @@ combineFiles({Source, SourceValid, _SourceContiguousTop,
 	    %% reflect compaction of Destination so truncate
 	    %% Destination and copy from Tmp back to the end
 	    {ok, 0} = file:position(TmpHdl, {bof, 0}),
-	    {ok, DestinationContiguousTop} =
-		file:position(DestinationHdl,
-			      {bof, DestinationContiguousTop}),
-	    ok = file:truncate(DestinationHdl),
-	    {ok, ExpectedSize} =
-		file:position(DestinationHdl,
-			      {bof, ExpectedSize}),
-	    ok = file:truncate(DestinationHdl),
-	    {ok, DestinationContiguousTop} =
-		file:position(DestinationHdl,
-			      {bof, DestinationContiguousTop}),
+	    ok = truncateAndExtendFile(DestinationHdl,
+				       DestinationContiguousTop, ExpectedSize),
 	    {ok, TmpSize} = file:copy(TmpHdl, DestinationHdl, TmpSize),
 	    %% position in DestinationHdl should now be
 	    %% DestinationValid