Fix for leaked file handles when not explicitly closed, added file stats code for checking for leaked file handles, and some refactoring of the view api.

git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@728764 13f79535-47bb-0310-9956-ffa450edef68

7 files changed, 61 insertions, 46 deletions

diff --git a/src/couchdb/couch_db.erl b/src/couchdb/couch_db.erl
index 6684156f..0e652b68 100644
--- a/src/couchdb/couch_db.erl
+++ b/src/couchdb/couch_db.erl
@@ -463,7 +463,7 @@ init({DbName, Filepath, Fd, Options}) ->
     gen_server:call(UpdaterPid, get_db).
 
 terminate(_Reason, Db) ->
-    exit(Db#db.update_pid, kill).
+    ok.
     
 handle_call({open_ref_counted_instance, OpenerPid}, _From, #db{fd=Fd}=Db) ->
     ok = couch_file:add_ref(Fd, OpenerPid),
diff --git a/src/couchdb/couch_db_updater.erl b/src/couchdb/couch_db_updater.erl
index 68c3a1fc..b4faefee 100644
--- a/src/couchdb/couch_db_updater.erl
+++ b/src/couchdb/couch_db_updater.erl
@@ -179,9 +179,9 @@ handle_cast({compact_done, CompactFilepath}, #db{filepath=Filepath}=Db) ->
         ?LOG_INFO("Compaction file still behind main file "
             "(update seq=~p. compact update seq=~p). Retrying.",
             [Db#db.update_seq, NewSeq]),
+        couch_file:close(NewFd),
         Pid = spawn_link(fun() -> start_copy_compact(Db) end),
         Db2 = Db#db{compactor_pid=Pid},
-        couch_file:close(NewFd),
         {noreply, Db2}
     end.
 
diff --git a/src/couchdb/couch_file.erl b/src/couchdb/couch_file.erl
index 06156324..9e60eb09 100644
--- a/src/couchdb/couch_file.erl
+++ b/src/couchdb/couch_file.erl
@@ -36,6 +36,7 @@ open(Filepath, Options) ->
     case gen_server:start_link(couch_file,
             {Filepath, Options, self(), Ref = make_ref()}, []) of
     {ok, Fd} ->
+        couch_file_stats:track_file(Fd),
         {ok, Fd};
     ignore ->
         % get the error
@@ -164,7 +165,9 @@ sync(Fd) ->
 %% Returns: ok
 %%----------------------------------------------------------------------
 close(Fd) ->
-    gen_server:cast(Fd, close).
+    Result = gen_server:cast(Fd, close),
+    catch unlink(Fd),
+    Result.
     
 close_maybe(Fd) ->
     gen_server:cast(Fd, {close_maybe, self()}).
@@ -185,6 +188,7 @@ add_ref(Fd, Pid) ->
 num_refs(Fd) ->
     gen_server:call(Fd, num_refs).
 
+
 write_header(Fd, Prefix, Data) ->
     TermBin = term_to_binary(Data),
     % the size of all the bytes written to the header, including the md5 signature (16 bytes)
@@ -286,6 +290,7 @@ init_status_error(ReturnPid, Ref, Error) ->
 % server functions
 
 init({Filepath, Options, ReturnPid, Ref}) ->
+    process_flag(trap_exit, true),
     case lists:member(create, Options) of
     true ->
         filelib:ensure_dir(Filepath),
@@ -325,8 +330,7 @@ init({Filepath, Options, ReturnPid, Ref}) ->
     end.
 
 
-terminate(_Reason, Fd) ->
-    file:close(Fd),
+terminate(_Reason, _Fd) ->
     ok.
 
 
@@ -366,7 +370,6 @@ handle_call(num_refs, _From, Fd) ->
     {reply, length(Monitors), Fd}.
 
 
-
 handle_cast(close, Fd) ->
     {stop,normal,Fd};
 handle_cast({close_maybe, Pid}, Fd) ->
@@ -388,6 +391,8 @@ handle_cast({drop_ref, Pid}, Fd) ->
 code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
 
+handle_info({'EXIT', _Pid, Reason}, Fd) ->
+    {stop, Reason, Fd};
 handle_info({'DOWN', MonitorRef, _Type, Pid, _Info}, Fd) ->
     {MonitorRef, _RefCount} = erase(Pid),
     maybe_close_async(Fd).
diff --git a/src/couchdb/couch_httpd_view.erl b/src/couchdb/couch_httpd_view.erl
index 13842149..35203ced 100644
--- a/src/couchdb/couch_httpd_view.erl
+++ b/src/couchdb/couch_httpd_view.erl
@@ -26,21 +26,20 @@ design_doc_view(Req, Db, Id, ViewName, Keys) ->
         update = Update,
         reduce = Reduce
     } = QueryArgs = parse_view_query(Req, Keys),
-    case couch_view:get_map_view({couch_db:name(Db), 
-            <<"_design/", Id/binary>>, ViewName, Update}) of
+    DesignId = <<"_design/", Id/binary>>,
+    case couch_view:get_map_view(Db, DesignId, ViewName, Update) of
     {ok, View} ->    
         output_map_view(Req, View, Db, QueryArgs, Keys);
     {not_found, Reason} ->
-        case couch_view:get_reduce_view({couch_db:name(Db),
-                <<"_design/", Id/binary>>, ViewName}) of
-        {ok, View} ->
+        case couch_view:get_reduce_view(Db, DesignId, ViewName, Update) of
+        {ok, ReduceView} ->
             parse_view_query(Req, Keys, true), % just for validation
             case Reduce of
             false ->
-                {reduce, _N, _Lang, MapView} = View,
+                MapView = couch_view:extract_map_view(ReduceView),
                 output_map_view(Req, MapView, Db, QueryArgs, Keys);
             _ ->
-                output_reduce_view(Req, View, QueryArgs, Keys)
+                output_reduce_view(Req, ReduceView, QueryArgs, Keys)
             end;
         _ ->
             throw({not_found, Reason})
@@ -72,11 +71,11 @@ handle_temp_view_req(#httpd{method='POST'}=Req, Db) ->
     Keys = proplists:get_value(<<"keys">>, Props, nil),
     case proplists:get_value(<<"reduce">>, Props, null) of
     null ->
-        {ok, View} = couch_view:get_map_view({temp, couch_db:name(Db), Language, MapSrc}),
+        {ok, View} = couch_view:get_temp_map_view(Db, Language, MapSrc),
         output_map_view(Req, View, Db, QueryArgs, Keys);
     RedSrc ->
-        {ok, View} = couch_view:get_reduce_view(
-                {temp,  couch_db:name(Db), Language, MapSrc, RedSrc}),
+        {ok, View} = couch_view:get_temp_reduce_view(Db, Language, MapSrc,
+                RedSrc),
         output_reduce_view(Req, View, QueryArgs, Keys)
     end;
 
diff --git a/src/couchdb/couch_server.erl b/src/couchdb/couch_server.erl
index 2a2f51e2..f0e85734 100644
--- a/src/couchdb/couch_server.erl
+++ b/src/couchdb/couch_server.erl
@@ -270,9 +270,8 @@ handle_call({create, DbName, Options}, _From, Server) ->
     Error ->
         {reply, Error, Server}
     end;
-handle_call({delete, DbName, Options}, _From, Server) ->
+handle_call({delete, DbName, _Options}, _From, Server) ->
     DbNameList = binary_to_list(DbName),
-    _UserCtx = proplists:get_value(user_ctx, Options, nil),
     case check_dbname(Server, DbNameList) of
     ok ->
         FullFilepath = get_full_filename(Server, DbNameList),
diff --git a/src/couchdb/couch_server_sup.erl b/src/couchdb/couch_server_sup.erl
index 9c74a1a3..f0157864 100644
--- a/src/couchdb/couch_server_sup.erl
+++ b/src/couchdb/couch_server_sup.erl
@@ -139,6 +139,12 @@ start_primary_services() ->
                 brutal_kill,
                 supervisor,
                 [couch_server]},
+            {couch_file_stats,
+                {couch_file_stats, start_link, []},
+                permanent,
+                brutal_kill,
+                supervisor,
+                [couch_file_stats]},
             {couch_db_update_event,
                 {gen_event, start_link, [{local, couch_db_update}]},
                 permanent,
diff --git a/src/couchdb/couch_view.erl b/src/couchdb/couch_view.erl
index 84f327e3..665cb6f7 100644
--- a/src/couchdb/couch_view.erl
+++ b/src/couchdb/couch_view.erl
@@ -13,9 +13,11 @@
 -module(couch_view).
 -behaviour(gen_server).
 
--export([start_link/0,fold/4,fold/5,less_json/2,less_json_keys/2,expand_dups/2,detuple_kvs/2]).
--export([init/1,terminate/2,handle_call/3,handle_cast/2,handle_info/2,code_change/3]).
--export([get_reduce_view/1, get_map_view/1,get_row_count/1,reduce_to_count/1, fold_reduce/7]).
+-export([start_link/0,fold/4,fold/5,less_json/2,less_json_keys/2,expand_dups/2,
+    detuple_kvs/2,init/1,terminate/2,handle_call/3,handle_cast/2,handle_info/2,
+    code_change/3,get_reduce_view/4,get_temp_reduce_view/4,get_temp_map_view/3,
+    get_map_view/4,get_row_count/1,reduce_to_count/1,fold_reduce/7,
+    extract_map_view/1]).
 
 -include("couch_db.hrl").
     
@@ -23,7 +25,8 @@ start_link() ->
     gen_server:start_link({local, couch_view}, couch_view, [], []).
 
 get_temp_updater(DbName, Type, MapSrc, RedSrc) ->
-    {ok, Pid} = gen_server:call(couch_view, {start_temp_updater, DbName, Type, MapSrc, RedSrc}),
+    {ok, Pid} = gen_server:call(couch_view,
+            {start_temp_updater, DbName, Type, MapSrc, RedSrc}),
     Pid.
 
 get_group_server(DbName, GroupId) ->
@@ -34,21 +37,28 @@ get_group_server(DbName, GroupId) ->
         throw(Error)
     end.
     
-get_updated_group(DbName, GroupId, Update) ->
-    couch_view_group:request_group(get_group_server(DbName, GroupId), seq_for_update(DbName, Update)).
+get_group(Db, GroupId, Update) ->
+    couch_view_group:request_group(
+            get_group_server(couch_db:name(Db), GroupId),
+            if Update -> couch_db:get_update_seq(Db); true -> 0 end).
 
-get_updated_group(temp, DbName, Type, MapSrc, RedSrc, Update) ->
-    couch_view_group:request_group(get_temp_updater(DbName, Type, MapSrc, RedSrc), seq_for_update(DbName, Update)).
+
+get_temp_group(Db, Type, MapSrc, RedSrc) ->
+    couch_view_group:request_group(
+            get_temp_updater(couch_db:name(Db), Type, MapSrc, RedSrc),
+            couch_db:get_update_seq(Db)).
 
 get_row_count(#view{btree=Bt}) ->
     {ok, {Count, _Reds}} = couch_btree:full_reduce(Bt),
     {ok, Count}.
 
-get_reduce_view({temp, DbName, Type, MapSrc, RedSrc}) ->
-    {ok, #group{views=[View]}} = get_updated_group(temp, DbName, Type, MapSrc, RedSrc, true),
-    {ok, {temp_reduce, View}};
-get_reduce_view({DbName, GroupId, Name}) ->
-    case get_updated_group(DbName, GroupId, true) of
+get_temp_reduce_view(Db, Type, MapSrc, RedSrc) ->
+    {ok, #group{views=[View]}} = get_temp_group(Db, Type, MapSrc, RedSrc),
+    {ok, {temp_reduce, View}}.
+
+
+get_reduce_view(Db, GroupId, Name, Update) ->
+    case get_group(Db, GroupId, Update) of
     {ok, #group{views=Views,def_lang=Lang}} ->
         get_reduce_view0(Name, Lang, Views);
     Error ->
@@ -63,6 +73,9 @@ get_reduce_view0(Name, Lang, [#view{reduce_funs=RedFuns}=View|Rest]) ->
         N -> {ok, {reduce, N, Lang, View}}
     end.
 
+extract_map_view({reduce, _N, _Lang, View}) ->
+    View.
+
 detuple_kvs([], Acc) ->
     lists:reverse(Acc);
 detuple_kvs([KV | Rest], Acc) ->
@@ -113,21 +126,14 @@ get_key_pos(Key, [{Key1,_Value}|_], N) when Key == Key1 ->
     N + 1;
 get_key_pos(Key, [_|Rest], N) ->
     get_key_pos(Key, Rest, N+1).
-       
-seq_for_update(DbName, Update) ->
-    case Update of
-    true ->
-        {ok, #db{update_seq=CurrentSeq}} = couch_db:open(DbName, []),
-        CurrentSeq;
-    _Else ->
-        0
-    end.  
-        
-get_map_view({temp, DbName, Type, Src}) ->
-    {ok, #group{views=[View]}} = get_updated_group(temp, DbName, Type, Src, [], true),
-    {ok, View};
-get_map_view({DbName, GroupId, Name, Update}) ->
-    case get_updated_group(DbName, GroupId, Update) of
+
+
+get_temp_map_view(Db, Type, Src) ->
+    {ok, #group{views=[View]}} = get_temp_group(Db, Type, Src, []),
+    {ok, View}.
+
+get_map_view(Db, GroupId, Name, Update) ->
+    case get_group(Db, GroupId, Update) of
     {ok, #group{views=Views}} ->
         get_map_view0(Name, Views);
     Error ->