realbatchwrite.patch

diff --git a/src/couchdb/couch_db_updater.erl b/src/couchdb/couch_db_updater.erl
index 19a4c16..6099d0a 100644
--- a/src/couchdb/couch_db_updater.erl
+++ b/src/couchdb/couch_db_updater.erl
@@ -439,15 +439,42 @@ refresh_validate_doc_funs(Db) ->
 
 % rev tree functions
 
-flush_trees(_Db, [], AccFlushedTrees) ->
-    {ok, lists:reverse(AccFlushedTrees)};
-flush_trees(#db{fd=Fd,header=Header}=Db,
-        [InfoUnflushed | RestUnflushed], AccFlushed) ->
-    #full_doc_info{update_seq=UpdateSeq, rev_tree=Unflushed} = InfoUnflushed,
-    Flushed = couch_key_tree:map(
-        fun(_Rev, Value) ->
+flush_trees(_Db, [], AccDocInfo, []) ->
+    {ok, lists:reverse(AccDocInfo)};
+flush_trees(#db{fd=Fd,header=Header}, [], AccDocInfo, AccUnflushed) ->
+    {ok, NewSummaryPointers} =
+    case Header#db_header.disk_version < 4 of
+    true ->
+        couch_file:append_terms(Fd, AccUnflushed);
+    false ->
+        couch_file:append_terms_md5(Fd, AccUnflushed)
+    end,
+    {Flushed, []} =
+    lists:foldl(
+        fun(#full_doc_info{update_seq=UpdateSeq, rev_tree=RevTree}=DocInfo,
+                {FlushedInfoAcc, UnusedSummaryPointers}) ->
+            {FlushedRevTree, UnusedSummaryPointers2} =
+            couch_key_tree:mapfoldl(
+                fun(_Rev, Value, SummaryPointers) ->
+                    case Value of
+                    #doc{deleted=IsDeleted} ->
+                        [NewSummaryPointer|Rest] = SummaryPointers,
+                        {{IsDeleted, NewSummaryPointer, UpdateSeq}, Rest};
+                    _ ->
+                        {Value, SummaryPointers}
+                    end
+                end, UnusedSummaryPointers, RevTree),
+            {[DocInfo#full_doc_info{rev_tree=FlushedRevTree}|FlushedInfoAcc],
+                UnusedSummaryPointers2}
+        end, {[], NewSummaryPointers}, AccDocInfo),
+    {ok, Flushed};
+flush_trees(#db{fd=Fd}=Db, [InfoUnflushed | RestUnflushed],
+        AccDocInfo, AccUnflushed) ->
+    #full_doc_info{rev_tree=RevTree} = InfoUnflushed,
+    AccUnflushed2 = couch_key_tree:foldl(
+        fun(_Rev, Value, Acc) ->
             case Value of
-            #doc{atts=Atts,deleted=IsDeleted}=Doc ->
+            #doc{atts=Atts}=Doc ->
                 % this node value is actually an unwritten document summary,
                 % write to disk.
                 % make sure the Fd in the written bins is the same Fd we are
@@ -468,20 +495,13 @@ flush_trees(#db{fd=Fd,header=Header}=Db,
                             " changed. Possibly retrying.", []),
                     throw(retry)
                 end,
-                {ok, NewSummaryPointer} =
-                case Header#db_header.disk_version < 4 of
-                true ->
-                    couch_file:append_term(Fd, {Doc#doc.body, DiskAtts});
-                false ->
-                    couch_file:append_term_md5(Fd, {Doc#doc.body, DiskAtts})
-                end,
-                {IsDeleted, NewSummaryPointer, UpdateSeq};
+                UnflushedBody = {Doc#doc.body, DiskAtts},
+                [UnflushedBody|Acc];
             _ ->
-                Value
+                Acc
             end
-        end, Unflushed),
-    flush_trees(Db, RestUnflushed, [InfoUnflushed#full_doc_info{rev_tree=Flushed} | AccFlushed]).
-
+        end, AccUnflushed, RevTree),
+    flush_trees(Db, RestUnflushed, [InfoUnflushed | AccDocInfo], AccUnflushed2).
 
 send_result(Client, Id, OriginalRevs, NewResult) ->
     % used to send a result to the client
@@ -605,7 +625,7 @@ update_docs_int(Db, DocsList, NonRepDocs, MergeConflicts, FullCommit) ->
 
     % Write out the document summaries (the bodies are stored in the nodes of
     % the trees, the attachments are already written to disk)
-    {ok, FlushedFullDocInfos} = flush_trees(Db2, NewFullDocInfos, []),
+    {ok, FlushedFullDocInfos} = flush_trees(Db2, NewFullDocInfos, [], []),
 
     {IndexFullDocInfos, IndexDocInfos} =
             new_index_entries(FlushedFullDocInfos, [], []),
diff --git a/src/couchdb/couch_file.erl b/src/couchdb/couch_file.erl
index 0a89171..f5e7530 100644
--- a/src/couchdb/couch_file.erl
+++ b/src/couchdb/couch_file.erl
@@ -27,6 +27,8 @@
 -export([append_term/2, pread_term/2, pread_iolist/2, write_header/2]).
 -export([pread_binary/2, read_header/1, truncate/2, upgrade_old_header/2]).
 -export([append_term_md5/2,append_binary_md5/2]).
+-export([append_terms/2, append_terms_md5/2]).
+-export([append_binaries/2, append_binaries_md5/2]).
 -export([init/1, terminate/2, handle_call/3, handle_cast/2, code_change/3, handle_info/2]).
 -export([delete/2,delete/3,init_delete_dir/1]).
 
@@ -74,6 +76,11 @@ append_term(Fd, Term) ->
 append_term_md5(Fd, Term) ->
     append_binary_md5(Fd, term_to_binary(Term)).
 
+append_terms(Fd, Terms) ->
+    append_terms(Fd, lists:map(fun term_to_binary/1, Terms)).
+
+append_terms_md5(Fd, Terms) ->
+    append_binaries_md5(Fd, lists:map(fun term_to_binary/1, Terms)).
 
 %%----------------------------------------------------------------------
 %% Purpose: To append an Erlang binary to the end of the file.
@@ -93,6 +100,22 @@ append_binary_md5(Fd, Bin) ->
     gen_server:call(Fd, {append_bin,
             [<<1:1/integer,Size:31/integer>>, couch_util:md5(Bin), Bin]}, infinity).
 
+append_binaries(Fd, Bins) ->
+    gen_server:call(Fd, {append_bins,
+            lists:map(
+                fun(Bin) ->
+                    Size = iolist_size(Bin),
+                    [<<0:1/integer,Size:31/integer>>, Bin]
+                end, Bins)}, infinity).
+
+append_binaries_md5(Fd, Bins) ->
+    gen_server:call(Fd, {append_bins,
+            lists:map(
+                fun(Bin) ->
+                    Size = iolist_size(Bin),
+                    [<<1:1/integer,Size:31/integer>>, couch_util:md5(Bin), Bin]
+                end, Bins)}, infinity).
+
 
 %%----------------------------------------------------------------------
 %% Purpose: Reads a term from a file that was written with append_term
@@ -331,6 +354,19 @@ handle_call({append_bin, Bin}, _From, #file{fd=Fd, eof=Pos}=File) ->
     Error ->
         {reply, Error, File}
     end;
+handle_call({append_bins, Bins}, _From, #file{fd=Fd, eof=Pos}=File) ->
+    {BlockPosList, NewPos} = lists:mapfoldl(
+        fun(Bin, OutPos) ->
+            Blocks = make_blocks(OutPos rem ?SIZE_BLOCK, Bin),
+            {{Blocks, OutPos}, OutPos+iolist_size(Blocks)}
+        end, Pos, Bins),
+    {BlockList, PosList} = lists:unzip(BlockPosList),
+    case file:write(Fd, BlockList) of
+    ok ->
+        {reply, {ok, PosList}, File#file{eof=NewPos}};
+    Error ->
+        {reply, Error, File}
+    end;
 handle_call({write_header, Bin}, _From, #file{fd=Fd, eof=Pos}=File) ->
     BinSize = size(Bin),
     case Pos rem ?SIZE_BLOCK of
diff --git a/src/couchdb/couch_key_tree.erl b/src/couchdb/couch_key_tree.erl
index 4fe09bf..ad4d092 100644
--- a/src/couchdb/couch_key_tree.erl
+++ b/src/couchdb/couch_key_tree.erl
@@ -13,7 +13,7 @@
 -module(couch_key_tree).
 
 -export([merge/2, find_missing/2, get_key_leafs/2, get_full_key_paths/2, get/2]).
--export([map/2, get_all_leafs/1, count_leafs/1, remove_leafs/2,
+-export([map/2, foldl/3, mapfoldl/3, get_all_leafs/1, count_leafs/1, remove_leafs/2,
     get_all_leafs_full/1,stem/2,map_leafs/2]).
 
 % a key tree looks like this:
@@ -294,6 +294,33 @@ map_simple(Fun, Pos, [{Key, Value, SubTree} | RestTree]) ->
             if SubTree == [] -> leaf; true -> branch end),
     [{Key, Value2, map_simple(Fun, Pos + 1, SubTree)} | map_simple(Fun, Pos, RestTree)].
 
+foldl(_Fun, Acc, []) ->
+    Acc;
+foldl(Fun, Acc, [{Pos, Tree}|Rest]) ->
+    Acc2 = foldl_simple(Fun, Acc, Pos, [Tree]),
+    foldl(Fun, Acc2, Rest).
+
+foldl_simple(_Fun, Acc, _Pos, []) ->
+    Acc;
+foldl_simple(Fun, Acc, Pos, [{Key, Value, SubTree} | RestTree]) ->
+    Acc2 = Fun({Pos, Key}, Value, Acc),
+    Acc3 = foldl_simple(Fun, Acc2, Pos + 1, SubTree),
+    foldl_simple(Fun, Acc3, Pos, RestTree).
+
+mapfoldl(_Fun, Acc, []) ->
+    {[], Acc};
+mapfoldl(Fun, Acc, [{Pos, Tree}|Rest]) ->
+    {[NewTree], Acc2} = mapfoldl_simple(Fun, Acc, Pos, [Tree]),
+    {NewRest, Acc3} = mapfoldl(Fun, Acc2, Rest),
+    {[{Pos, NewTree} | NewRest], Acc3}.
+
+mapfoldl_simple(_Fun, Acc, _Pos, []) ->
+    {[], Acc};
+mapfoldl_simple(Fun, Acc, Pos, [{Key, Value, Subtree} | RestTree ]) ->
+    {Value2, Acc2} = Fun({Pos, Key}, Value, Acc),
+    {NewSubTree, Acc3} = mapfoldl_simple(Fun, Acc2, Pos, Subtree),
+    {NewRestTree, Acc4} = mapfoldl_simple(Fun, Acc3, Pos, RestTree),
+    {[{Key, Value2, NewSubTree} | NewRestTree], Acc4}.
 
 map_leafs(_Fun, []) ->
     [];