diff options
Diffstat (limited to 'apps/couch/src/couch_stream.erl')
| -rw-r--r-- | apps/couch/src/couch_stream.erl | 44 |
1 files changed, 41 insertions, 3 deletions
diff --git a/apps/couch/src/couch_stream.erl b/apps/couch/src/couch_stream.erl index 04c17770..60af1c2b 100644 --- a/apps/couch/src/couch_stream.erl +++ b/apps/couch/src/couch_stream.erl @@ -24,7 +24,7 @@ -define(DEFAULT_STREAM_CHUNK, 16#00100000). % 1 meg chunks when streaming data --export([open/1, open/3, close/1, write/2, foldl/4, foldl/5, foldl_decode/6, +-export([open/1, open/3, close/1, write/2, foldl/4, foldl/5, range_foldl/6, foldl_decode/6, old_foldl/5,old_copy_to_new_stream/4]). -export([copy_to_new_stream/3,old_read_term/2]). -export([init/1, terminate/2, handle_call/3]). @@ -112,22 +112,60 @@ foldl_decode(Fd, PosList, Md5, Enc, Fun, Acc) -> foldl(_Fd, [], Md5, Md5Acc, _Fun, Acc) -> Md5 = couch_util:md5_final(Md5Acc), Acc; +foldl(Fd, [{Pos, _Size}], Md5, Md5Acc, Fun, Acc) -> % 0110 UPGRADE CODE + foldl(Fd, [Pos], Md5, Md5Acc, Fun, Acc); foldl(Fd, [Pos], Md5, Md5Acc, Fun, Acc) -> {ok, Bin} = couch_file:pread_iolist(Fd, Pos), Md5 = couch_util:md5_final(couch_util:md5_update(Md5Acc, Bin)), Fun(Bin, Acc); +foldl(Fd, [{Pos, _Size}|Rest], Md5, Md5Acc, Fun, Acc) -> + foldl(Fd, [Pos|Rest], Md5, Md5Acc, Fun, Acc); foldl(Fd, [Pos|Rest], Md5, Md5Acc, Fun, Acc) -> {ok, Bin} = couch_file:pread_iolist(Fd, Pos), foldl(Fd, Rest, Md5, couch_util:md5_update(Md5Acc, Bin), Fun, Fun(Bin, Acc)). +range_foldl(Fd, PosList, From, To, Fun, Acc) -> + range_foldl(Fd, PosList, From, To, 0, Fun, Acc). + +range_foldl(_Fd, _PosList, _From, To, Off, _Fun, Acc) when Off >= To -> + Acc; +range_foldl(Fd, [Pos|Rest], From, To, Off, Fun, Acc) when is_integer(Pos) -> % old-style attachment + {ok, Bin} = couch_file:pread_iolist(Fd, Pos), + range_foldl(Fd, [{Pos, iolist_size(Bin)}] ++ Rest, From, To, Off, Fun, Acc); +range_foldl(Fd, [{_Pos, Size}|Rest], From, To, Off, Fun, Acc) when From > Off + Size -> + range_foldl(Fd, Rest, From, To, Off + Size, Fun, Acc); +range_foldl(Fd, [{Pos, Size}|Rest], From, To, Off, Fun, Acc) -> + {ok, Bin} = couch_file:pread_iolist(Fd, Pos), + Bin1 = if + From =< Off andalso To >= Off + Size -> Bin; %% the whole block is covered + true -> + PrefixLen = clip(From - Off, 0, Size), + PostfixLen = clip(Off + Size - To, 0, Size), + MatchLen = Size - PrefixLen - PostfixLen, + <<_Prefix:PrefixLen/binary,Match:MatchLen/binary,_Postfix:PostfixLen/binary>> = iolist_to_binary(Bin), + Match + end, + range_foldl(Fd, Rest, From, To, Off + Size, Fun, Fun(Bin1, Acc)). + +clip(Value, Lo, Hi) -> + if + Value < Lo -> Lo; + Value > Hi -> Hi; + true -> Value + end. + foldl_decode(_DecFun, _Fd, [], Md5, Md5Acc, _Fun, Acc) -> Md5 = couch_util:md5_final(Md5Acc), Acc; +foldl_decode(DecFun, Fd, [{Pos, _Size}], Md5, Md5Acc, Fun, Acc) -> + foldl_decode(DecFun, Fd, [Pos], Md5, Md5Acc, Fun, Acc); foldl_decode(DecFun, Fd, [Pos], Md5, Md5Acc, Fun, Acc) -> {ok, EncBin} = couch_file:pread_iolist(Fd, Pos), Md5 = couch_util:md5_final(couch_util:md5_update(Md5Acc, EncBin)), Bin = DecFun(EncBin), Fun(Bin, Acc); +foldl_decode(DecFun, Fd, [{Pos, _Size}|Rest], Md5, Md5Acc, Fun, Acc) -> + foldl_decode(DecFun, Fd, [Pos|Rest], Md5, Md5Acc, Fun, Acc); foldl_decode(DecFun, Fd, [Pos|Rest], Md5, Md5Acc, Fun, Acc) -> {ok, EncBin} = couch_file:pread_iolist(Fd, Pos), Bin = DecFun(EncBin), @@ -227,7 +265,7 @@ handle_call({write, Bin}, _From, Stream) -> {ok, Pos} = couch_file:append_binary(Fd, WriteBin2), WrittenLen2 = WrittenLen + iolist_size(WriteBin2), Md5_2 = couch_util:md5_update(Md5, WriteBin2), - Written2 = [Pos|Written] + Written2 = [{Pos, iolist_size(WriteBin2)}|Written] end, {reply, ok, Stream#stream{ @@ -265,7 +303,7 @@ handle_call(close, _From, Stream) -> {lists:reverse(Written), WrittenLen, IdenLen, Md5Final, IdenMd5Final}; _ -> {ok, Pos} = couch_file:append_binary(Fd, WriteBin2), - StreamInfo = lists:reverse(Written, [Pos]), + StreamInfo = lists:reverse(Written, [{Pos, iolist_size(WriteBin2)}]), StreamLen = WrittenLen + iolist_size(WriteBin2), {StreamInfo, StreamLen, IdenLen, Md5Final, IdenMd5Final} end, |