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Diffstat (limited to 'lib/stdlib/src/dets_v8.erl')
| -rw-r--r-- | lib/stdlib/src/dets_v8.erl | 1594 |
1 files changed, 0 insertions, 1594 deletions
diff --git a/lib/stdlib/src/dets_v8.erl b/lib/stdlib/src/dets_v8.erl deleted file mode 100644 index 1bf53d91b1..0000000000 --- a/lib/stdlib/src/dets_v8.erl +++ /dev/null @@ -1,1594 +0,0 @@ -%% -%% %CopyrightBegin% -%% -%% Copyright Ericsson AB 2001-2016. All Rights Reserved. -%% -%% Licensed under the Apache License, Version 2.0 (the "License"); -%% you may not use this file except in compliance with the License. -%% You may obtain a copy of the License at -%% -%% http://www.apache.org/licenses/LICENSE-2.0 -%% -%% Unless required by applicable law or agreed to in writing, software -%% distributed under the License is distributed on an "AS IS" BASIS, -%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -%% See the License for the specific language governing permissions and -%% limitations under the License. -%% -%% %CopyrightEnd% -%% --module(dets_v8). - -%% Dets files, implementation part. This module handles versions up to -%% and including 8(c). To be called from dets.erl only. - --export([mark_dirty/1, read_file_header/2, - check_file_header/2, do_perform_save/1, initiate_file/11, - init_freelist/2, fsck_input/4, - bulk_input/3, output_objs/4, write_cache/1, may_grow/3, - find_object/2, re_hash/2, slot_objs/2, scan_objs/8, - db_hash/2, no_slots/1, table_parameters/1]). - --export([file_info/1, v_segments/1]). - --export([cache_segps/3]). - -%% For backward compatibility. --export([sz2pos/1]). - --dialyzer(no_improper_lists). - --compile({inline, [{sz2pos,1},{scan_skip,7}]}). --compile({inline, [{skip_bytes,5}, {get_segp,1}]}). --compile({inline, [{wl_lookup,5}]}). --compile({inline, [{actual_seg_size,0}]}). - --include("dets.hrl"). - -%% The layout of the file is : -%% -%% bytes decsription -%% ---------------------- File header -%% 4 FreelistsPointer -%% 4 Cookie -%% 4 ClosedProperly (pos=8) -%% 4 Type (pos=12) -%% 4 Version (pos=16) -%% 4 M -%% 4 Next -%% 4 KeyPos -%% 4 NoObjects -%% 4 N -%% ------------------ end of file header -%% 4*8192 SegmentArray -%% ------------------ -%% 4*256 First segment -%% ----------------------------- This is BASE. -%% ??? Objects (free and alive) -%% 4*256 Second segment (2 kB now, due to a bug) -%% ??? Objects (free and alive) -%% ... more objects and segments ... -%% ----------------------------- -%% ??? Free lists -%% ----------------------------- -%% 4 File size, in bytes. - -%% The first slot (0) in the segment array always points to the -%% pre-allocated first segment. -%% Before we can find an object we must find the slot where the -%% object resides. Each slot is a (possibly empty) list (or chain) of -%% objects that hash to the same slot. If the value stored in the -%% slot is zero, the slot chain is empty. If the slot value is -%% non-zero, the value points to a position in the file where the -%% chain starts. Each object in a chain has the following layout: -%% -%% bytes decsription -%% -------------------- -%% 4 Pointer to the next object of the chain. -%% 4 Size of the object in bytes (Sz). -%% 4 Status (FREE or ACTIVE) -%% Sz Binary representing the object -%% -%% The status field is used while repairing a file (but not next or size). -%% -%%|---------------| -%%| head | -%%| | -%%| | -%%|_______________| -%%| |------| -%%|___seg ptr1____| | -%%| | | -%%|__ seg ptr 2___| | -%%| | | segment 1 -%%| .... | V _____________ -%% | | -%% | | -%% |___slot 0 ____| -%% | | -%% |___slot 1 ____|-----| -%% | | | -%% | ..... | | 1:st obj in slot 1 -%% V segment 1 -%% |-----------| -%% | next | -%% |___________| -%% | size | -%% |___________| -%% | status | -%% |___________| -%% | | -%% | | -%% | obj | -%% | | - -%%% -%%% File header -%%% - --define(HEADSZ, 40). % The size of the file header, in bytes. --define(SEGSZ, 256). % Size of a segment, in words. --define(SEGSZ_LOG2, 8). --define(SEGARRSZ, 8192). % Maximal number of segments. --define(SEGADDR(SegN), (?HEADSZ + (4 * (SegN)))). --define(BASE, ?SEGADDR((?SEGSZ + ?SEGARRSZ))). --define(MAXOBJS, (?SEGSZ * ?SEGARRSZ)). % 2 M objects - --define(SLOT2SEG(S), ((S) bsr ?SEGSZ_LOG2)). - -%% BIG is used for hashing. BIG must be greater than the maximum -%% number of slots, currently MAXOBJS. --define(BIG, 16#ffffff). - -%% Hard coded positions into the file header: --define(FREELIST_POS, 0). --define(CLOSED_PROPERLY_POS, 8). --define(D_POS, 20). --define(NO_OBJECTS_POS, (?D_POS + 12)). - -%% The version of a dets file is indicated by the ClosedProperly -%% field. Version 6 was used in the R1A release, and version 7 in the -%% R1B release up to and including the R3B01 release. Both version 6 -%% and version 7 indicate properly closed files by the value -%% CLOSED_PROPERLY. -%% -%% The current version, 8, has three sub-versions: -%% -%% - 8(a), indicated by the value CLOSED_PROPERLY (same as in versions 6 -%% and 7), introduced in R3B02; -%% - 8(b), indicated by the value CLOSED_PROPERLY2(_NEED_COMPACTING), -%% introduced in R5A and used up to and including R6A; -%% - 8(c), indicated by the value CLOSED_PROPERLY_NEW_HASH(_NEED_COMPACTING), -%% in use since R6B. -%% -%% The difference between the 8(a) and the 8(b) versions is the format -%% used for free lists saved on dets files. -%% The 8(c) version uses a different hashing algorithm, erlang:phash -%% (former versions use erlang:hash). -%% Version 8(b) files are only converted to version 8(c) if repair is -%% done, so we need compatibility with 8(b) for a _long_ time. -%% -%% There are known bugs due to the fact that keys and objects are -%% sometimes compared (==) and sometimes matched (=:=). The version -%% used by default (9, see dets_v9.erl) does not have this problem. - --define(NOT_PROPERLY_CLOSED,0). --define(CLOSED_PROPERLY,1). --define(CLOSED_PROPERLY2,2). --define(CLOSED_PROPERLY2_NEED_COMPACTING,3). --define(CLOSED_PROPERLY_NEW_HASH,4). --define(CLOSED_PROPERLY_NEW_HASH_NEED_COMPACTING,5). - --define(FILE_FORMAT_VERSION, 8). --define(CAN_BUMP_BY_REPAIR, [6, 7]). --define(CAN_CONVERT_FREELIST, [8]). - -%%% -%%% Object header (next, size, status). -%%% - --define(OHDSZ, 12). % The size of the object header, in bytes. --define(STATUS_POS, 8). % Position of the status field. - -%% The size of each object is a multiple of 16. -%% BUMP is used when repairing files. --define(BUMP, 16). - --define(ReadAhead, 512). - -%%-define(DEBUGF(X,Y), io:format(X, Y)). --define(DEBUGF(X,Y), void). - -%% -> ok | throw({NewHead,Error}) -mark_dirty(Head) -> - Dirty = [{?CLOSED_PROPERLY_POS, <<?NOT_PROPERLY_CLOSED:32>>}], - {_NewHead, ok} = dets_utils:pwrite(Head, Dirty), - ok = dets_utils:sync(Head), - {ok, _Pos} = dets_utils:position(Head, Head#head.freelists_p), - ok = dets_utils:truncate(Head, cur). - -%% -> {ok, head()} | throw(Error) -initiate_file(Fd, Tab, Fname, Type, Kp, MinSlots, MaxSlots, - Ram, CacheSz, Auto, _DoInitSegments) -> - Freelist = 0, - Cookie = ?MAGIC, - ClosedProperly = ?NOT_PROPERLY_CLOSED, % immediately overwritten - Version = ?FILE_FORMAT_VERSION, - Factor = est_no_segments(MinSlots), - N = 0, - M = Next = ?SEGSZ * Factor, - NoObjects = 0, - dets_utils:pwrite(Fd, Fname, 0, - <<Freelist:32, - Cookie:32, - ClosedProperly:32, - (dets_utils:type_to_code(Type)):32, - Version:32, - M:32, - Next:32, - Kp:32, - NoObjects:32, - N:32, - 0:(?SEGARRSZ*4)/unit:8, % Initialize SegmentArray - 0:(?SEGSZ*4)/unit:8>>), % Initialize first segment - %% We must set the first slot of the segment pointer array to - %% point to the first segment - Pos = ?SEGADDR(0), - SegP = (?HEADSZ + (4 * ?SEGARRSZ)), - dets_utils:pwrite(Fd, Fname, Pos, <<SegP:32>>), - segp_cache(Pos, SegP), - - Ftab = dets_utils:init_alloc(?BASE), - H0 = #head{freelists=Ftab, fptr = Fd, base = ?BASE}, - {H1, Ws} = init_more_segments(H0, 1, Factor, undefined, []), - - %% This is not optimal but simple: always initiate the segments. - dets_utils:pwrite(Fd, Fname, Ws), - - %% Return a new nice head structure - Head = #head{ - m = M, - m2 = M * 2, - next = Next, - fptr = Fd, - no_objects = NoObjects, - n = N, - type = Type, - update_mode = dirty, - freelists = H1#head.freelists, - auto_save = Auto, - hash_bif = phash, - keypos = Kp, - min_no_slots = Factor * ?SEGSZ, - max_no_slots = no_segs(MaxSlots) * ?SEGSZ, - - ram_file = Ram, - filename = Fname, - name = Tab, - cache = dets_utils:new_cache(CacheSz), - version = Version, - bump = ?BUMP, - base = ?BASE, - mod = ?MODULE - }, - {ok, Head}. - -est_no_segments(MinSlots) when 1 + ?SLOT2SEG(MinSlots) > ?SEGARRSZ -> - ?SEGARRSZ; -est_no_segments(MinSlots) -> - 1 + ?SLOT2SEG(MinSlots). - -init_more_segments(Head, SegNo, Factor, undefined, Ws) when SegNo < Factor -> - init_more_segments(Head, SegNo, Factor, seg_zero(), Ws); -init_more_segments(Head, SegNo, Factor, SegZero, Ws) when SegNo < Factor -> - {NewHead, W} = allocate_segment(Head, SegZero, SegNo), - init_more_segments(NewHead, SegNo+1, Factor, SegZero, W++Ws); -init_more_segments(Head, _SegNo, _Factor, _SegZero, Ws) -> - {Head, Ws}. - -allocate_segment(Head, SegZero, SegNo) -> - %% may throw error: - {NewHead, Segment, _} = dets_utils:alloc(Head, 4 * ?SEGSZ), - InitSegment = {Segment, SegZero}, - Pos = ?SEGADDR(SegNo), - segp_cache(Pos, Segment), - SegPointer = {Pos, <<Segment:32>>}, - {NewHead, [InitSegment, SegPointer]}. - -%% Read free lists (using a Buddy System) from file. -init_freelist(Head, {convert_freelist,_Version}) -> - %% This function converts the saved freelist of the form - %% [{Slot1,Addr1},{Addr1,Addr2},...,{AddrN,0},{Slot2,Addr},...] - %% i.e each slot is a linked list which ends with a 0. - %% This is stored in a bplus_tree per Slot. - %% Each Slot is a position in a tuple. - - Ftab = dets_utils:empty_free_lists(), - Pos = Head#head.freelists_p, - case catch prterm(Head, Pos, ?OHDSZ) of - {0, _Sz, Term} -> - FreeList1 = lists:reverse(Term), - FreeList = dets_utils:init_slots_from_old_file(FreeList1, Ftab), - Head#head{freelists = FreeList, base = ?BASE}; - _ -> - throw({error, {bad_freelists, Head#head.filename}}) - end; -init_freelist(Head, _) -> - %% bplus_tree stored as is - Pos = Head#head.freelists_p, - case catch prterm(Head, Pos, ?OHDSZ) of - {0, _Sz, Term} -> - Head#head{freelists = Term, base = ?BASE}; - _ -> - throw({error, {bad_freelists, Head#head.filename}}) - end. - -%% -> {ok, Fd, fileheader()} | throw(Error) -read_file_header(Fd, FileName) -> - {ok, Bin} = dets_utils:pread_close(Fd, FileName, 0, ?HEADSZ), - [Freelist, Cookie, CP, Type2, Version, M, Next, Kp, NoObjects, N] = - bin2ints(Bin), - {ok, EOF} = dets_utils:position_close(Fd, FileName, eof), - {ok, <<FileSize:32>>} = dets_utils:pread_close(Fd, FileName, EOF-4, 4), - FH = #fileheader{freelist = Freelist, - fl_base = ?BASE, - cookie = Cookie, - closed_properly = CP, - type = dets_utils:code_to_type(Type2), - version = Version, - m = M, - next = Next, - keypos = Kp, - no_objects = NoObjects, - min_no_slots = ?DEFAULT_MIN_NO_SLOTS, - max_no_slots = ?DEFAULT_MAX_NO_SLOTS, - trailer = FileSize, - eof = EOF, - n = N, - mod = ?MODULE}, - {ok, Fd, FH}. - -%% -> {ok, head(), ExtraInfo} | {error, Reason} (Reason lacking file name) -%% ExtraInfo = {convert_freelist, Version} | true | need_compacting -check_file_header(FH, Fd) -> - Test = - if - FH#fileheader.cookie =/= ?MAGIC -> - {error, not_a_dets_file}; - FH#fileheader.type =:= badtype -> - {error, invalid_type_code}; - FH#fileheader.version =/= ?FILE_FORMAT_VERSION -> - case lists:member(FH#fileheader.version, - ?CAN_BUMP_BY_REPAIR) of - true -> - {error, version_bump}; - false -> - {error, bad_version} - end; - FH#fileheader.trailer =/= FH#fileheader.eof -> - {error, not_closed}; - FH#fileheader.closed_properly =:= ?CLOSED_PROPERLY -> - case lists:member(FH#fileheader.version, - ?CAN_CONVERT_FREELIST) of - true -> - {ok, {convert_freelist, FH#fileheader.version}, hash}; - false -> - {error, not_closed} % should not happen - end; - FH#fileheader.closed_properly =:= ?CLOSED_PROPERLY2 -> - {ok, true, hash}; - FH#fileheader.closed_properly =:= - ?CLOSED_PROPERLY2_NEED_COMPACTING -> - {ok, need_compacting, hash}; - FH#fileheader.closed_properly =:= ?CLOSED_PROPERLY_NEW_HASH -> - {ok, true, phash}; - FH#fileheader.closed_properly =:= - ?CLOSED_PROPERLY_NEW_HASH_NEED_COMPACTING -> - {ok, need_compacting, phash}; - FH#fileheader.closed_properly =:= ?NOT_PROPERLY_CLOSED -> - {error, not_closed}; - FH#fileheader.closed_properly > - ?CLOSED_PROPERLY_NEW_HASH_NEED_COMPACTING -> - {error, not_closed}; - true -> - {error, not_a_dets_file} - end, - case Test of - {ok, ExtraInfo, HashAlg} -> - H = #head{ - m = FH#fileheader.m, - m2 = FH#fileheader.m * 2, - next = FH#fileheader.next, - fptr = Fd, - no_objects= FH#fileheader.no_objects, - n = FH#fileheader.n, - type = FH#fileheader.type, - update_mode = saved, - auto_save = infinity, % not saved on file - fixed = false, % not saved on file - freelists_p = FH#fileheader.freelist, - hash_bif = HashAlg, - keypos = FH#fileheader.keypos, - min_no_slots = FH#fileheader.min_no_slots, - max_no_slots = FH#fileheader.max_no_slots, - version = ?FILE_FORMAT_VERSION, - mod = ?MODULE, - bump = ?BUMP, - base = FH#fileheader.fl_base}, - {ok, H, ExtraInfo}; - Error -> - Error - end. - -cache_segps(Fd, FileName, M) -> - NSegs = no_segs(M), - {ok, Bin} = dets_utils:pread_close(Fd, FileName, ?HEADSZ, 4 * NSegs), - Fun = fun(S, P) -> segp_cache(P, S), P+4 end, - lists:foldl(Fun, ?HEADSZ, bin2ints(Bin)). - -no_segs(NoSlots) -> - ?SLOT2SEG(NoSlots - 1) + 1. - -bin2ints(<<Int:32, B/binary>>) -> - [Int | bin2ints(B)]; -bin2ints(<<>>) -> - []. - -%%% -%%% Repair, conversion and initialization of a dets file. -%%% - -bulk_input(Head, InitFun, Cntrs) -> - bulk_input(Head, InitFun, Cntrs, make_ref()). - -bulk_input(Head, InitFun, Cntrs, Ref) -> - fun(close) -> - ok; - (read) -> - case catch {Ref, InitFun(read)} of - {Ref, end_of_input} -> - end_of_input; - {Ref, {L0, NewInitFun}} when is_list(L0), - is_function(NewInitFun) -> - Kp = Head#head.keypos, - case catch bulk_objects(L0, Head, Cntrs, Kp, []) of - {'EXIT', _Error} -> - _ = (catch NewInitFun(close)), - {error, invalid_objects_list}; - L -> - {L, bulk_input(Head, NewInitFun, Cntrs, Ref)} - end; - {Ref, Value} -> - {error, {init_fun, Value}}; - Error -> - throw({thrown, Error}) - end - end. - -bulk_objects([T | Ts], Head, Cntrs, Kp, L) -> - BT = term_to_binary(T), - Sz = byte_size(BT), - LogSz = sz2pos(Sz+?OHDSZ), - count_object(Cntrs, LogSz), - Key = element(Kp, T), - bulk_objects(Ts, Head, Cntrs, Kp, [make_object(Head, Key, LogSz, BT) | L]); -bulk_objects([], _Head, _Cntrs, _Kp, L) -> - L. - --define(FSCK_SEGMENT, 10000). - --define(DCT(D, CT), [D | CT]). - --define(VNEW(N, E), erlang:make_tuple(N, E)). --define(VSET(I, V, E), setelement(I, V, E)). --define(VGET(I, V), element(I, V)). - -%% OldVersion not used, assuming later versions have been converted already. -output_objs(OldVersion, Head, SlotNumbers, Cntrs) -> - fun(close) -> - {ok, 0, Head}; - ([]) -> - output_objs(OldVersion, Head, SlotNumbers, Cntrs); - (L) -> - %% Descending sizes. - Count = lists:sort(ets:tab2list(Cntrs)), - RCount = lists:reverse(Count), - NoObjects = lists:foldl(fun({_Sz,No}, A) -> A + No end, 0, Count), - {_, MinSlots, _} = SlotNumbers, - if - %% Using number of objects for bags and duplicate bags - %% is not ideal; number of (unique) keys should be - %% used instead. The effect is that there will be more - %% segments than "necessary". - MinSlots =/= bulk_init, - abs(?SLOT2SEG(NoObjects) - ?SLOT2SEG(MinSlots)) > 5, - (NoObjects < ?MAXOBJS) -> - {try_again, NoObjects}; - true -> - Head1 = Head#head{no_objects = NoObjects}, - SegSz = actual_seg_size(), - {_, End, _} = dets_utils:alloc(Head, SegSz-1), - %% Now {LogSize,NoObjects} in Cntrs is replaced by - %% {LogSize,Position,{FileName,FileDescriptor},NoObjects}. - {Head2, CT} = allocate_all_objects(Head1, RCount, Cntrs), - [E | Es] = bin2term(L, []), - {NE, Acc, DCT1} = - output_slots(E, Es, [E], Head2, ?DCT(0, CT)), - NDCT = write_all_sizes(DCT1, Cntrs), - Max = ets:info(Cntrs, size), - output_objs2(NE, Acc, Head2, Cntrs, NDCT, End, Max,Max) - end - end. - -output_objs2(E, Acc, Head, Cntrs, DCT, End, 0, MaxNoChunks) -> - NDCT = write_all_sizes(DCT, Cntrs), - output_objs2(E, Acc, Head, Cntrs, NDCT, End, MaxNoChunks, MaxNoChunks); -output_objs2(E, Acc, Head, Cntrs, DCT, End, ChunkI, MaxNoChunks) -> - fun(close) -> - DCT1 = output_slot(Acc, Head, DCT), - NDCT = write_all_sizes(DCT1, Cntrs), - ?DCT(NoDups, CT) = NDCT, - [SegAddr | []] = ?VGET(tuple_size(CT), CT), - FinalZ = End - SegAddr, - [{?FSCK_SEGMENT, _, {FileName, Fd}, _}] = - ets:lookup(Cntrs, ?FSCK_SEGMENT), - ok = dets_utils:fwrite(Fd, FileName, - dets_utils:make_zeros(FinalZ)), - NewHead = Head#head{no_objects = Head#head.no_objects - NoDups}, - {ok, NoDups, NewHead}; - (L) -> - Es = bin2term(L, []), - {NE, NAcc, NDCT} = output_slots(E, Es, Acc, Head, DCT), - output_objs2(NE, NAcc, Head, Cntrs, NDCT, End, - ChunkI-1, MaxNoChunks) - end. - -%% By allocating bigger objects before smaller ones, holes in the -%% buddy system memory map are avoided. Unfortunately, the segments -%% are always allocated first, so if there are objects bigger than a -%% segment, there is a hole to handle. (Haven't considered placing the -%% segments among other objects of the same size.) -allocate_all_objects(Head, Count, Cntrs) -> - SegSize = actual_seg_size(), - {Head1, HSz, HN, HA} = alloc_hole(Count, Head, SegSize), - {Max, _} = hd(Count), - CT = ?VNEW(Max+1, not_used), - {Head2, NCT} = allocate_all(Head1, Count, Cntrs, CT), - Head3 = free_hole(Head2, HSz, HN, HA), - {Head3, NCT}. - -alloc_hole([{LSize,_} | _], Head, SegSz) when ?POW(LSize-1) > SegSz -> - {_, SegAddr, _} = dets_utils:alloc(Head, SegSz-1), - Size = ?POW(LSize-1)-1, - {_, Addr, _} = dets_utils:alloc(Head, Size), - N = (Addr - SegAddr) div SegSz, - Head1 = dets_utils:alloc_many(Head, SegSz, N, SegAddr), - {Head1, SegSz-1, N, SegAddr}; -alloc_hole(_Count, Head, _SegSz) -> - {Head, 0, 0, 0}. - -free_hole(Head, _Size, 0, _Addr) -> - Head; -free_hole(Head, Size, N, Addr) -> - {Head1, _} = dets_utils:free(Head, Addr, Size), - free_hole(Head1, Size, N-1, Addr+Size+1). - -%% One (temporary) file for each buddy size, write all objects of that -%% size to the file. -allocate_all(Head, [{LSize,NoObjects} | Count], Cntrs, CT) -> - Size = ?POW(LSize-1)-1, - {_Head, Addr, _} = dets_utils:alloc(Head, Size), - NewHead = dets_utils:alloc_many(Head, Size+1, NoObjects, Addr), - {FileName, Fd} = temp_file(Head, LSize), - true = ets:insert(Cntrs, {LSize, Addr, {FileName, Fd}, NoObjects}), - NCT = ?VSET(LSize, CT, [Addr | []]), - allocate_all(NewHead, Count, Cntrs, NCT); -allocate_all(Head, [], Cntrs, CT) -> - %% Note that space for the segments has been allocated already. - %% And one file for the segments... - {FileName, Fd} = temp_file(Head, ?FSCK_SEGMENT), - Addr = ?SEGADDR(?SEGARRSZ), - true = ets:insert(Cntrs, {?FSCK_SEGMENT, Addr, {FileName, Fd}, 0}), - NCT = ?VSET(tuple_size(CT), CT, [Addr | []]), - {Head, NCT}. - -temp_file(Head, N) -> - TmpName = lists:concat([Head#head.filename, '.', N]), - {ok, Fd} = dets_utils:open(TmpName, [raw, binary, write]), - {TmpName, Fd}. - -bin2term([<<Slot:32, LogSize:8, BinTerm/binary>> | BTs], L) -> - bin2term(BTs, [{Slot, LogSize, BinTerm} | L]); -bin2term([], L) -> - lists:reverse(L). - -write_all_sizes(?DCT(D, CT), Cntrs) -> - ?DCT(D, write_sizes(1, tuple_size(CT), CT, Cntrs)). - -write_sizes(Sz, Sz, CT, Cntrs) -> - write_size(Sz, ?FSCK_SEGMENT, CT, Cntrs); -write_sizes(Sz, MaxSz, CT, Cntrs) -> - NCT = write_size(Sz, Sz, CT, Cntrs), - write_sizes(Sz+1, MaxSz, NCT, Cntrs). - -write_size(Sz, I, CT, Cntrs) -> - case ?VGET(Sz, CT) of - not_used -> - CT; - [Addr | L] -> - {FileName, Fd} = ets:lookup_element(Cntrs, I, 3), - case file:write(Fd, lists:reverse(L)) of - ok -> - ?VSET(Sz, CT, [Addr | []]); - Error -> - dets_utils:file_error(FileName, Error) - end - end. - -output_slots(E, [E1 | Es], Acc, Head, DCT) - when element(1, E) =:= element(1, E1) -> - output_slots(E1, Es, [E1 | Acc], Head, DCT); -output_slots(_E, [E | L], Acc, Head, DCT) -> - NDCT = output_slot(Acc, Head, DCT), - output_slots(E, L, [E], Head, NDCT); -output_slots(E, [], Acc, _Head, DCT) -> - {E, Acc, DCT}. - -output_slot([E], _Head, ?DCT(D, CT)) -> - ?DCT(D, output_slot([{foo, E}], 0, foo, CT)); -output_slot(Es0, Head, ?DCT(D, CT)) -> - Kp = Head#head.keypos, - Fun = fun({_Slot, _LSize, BinTerm} = E) -> - Key = element(Kp, binary_to_term(BinTerm)), - {Key, E} - end, - Es = lists:map(Fun, Es0), - NEs = case Head#head.type of - set -> - [{Key0,_} = E | L0] = lists:sort(Es), - choose_one(lists:sort(L0), Key0, [E]); - bag -> - lists:usort(Es); - duplicate_bag -> - lists:sort(Es) - end, - Dups = D + length(Es) - length(NEs), - ?DCT(Dups, output_slot(NEs, 0, foo, CT)). - -choose_one([{Key,_} | Es], Key, L) -> - choose_one(Es, Key, L); -choose_one([{Key,_} = E | Es], _Key, L) -> - choose_one(Es, Key, [E | L]); -choose_one([], _Key, L) -> - L. - -output_slot([E | Es], Next, _Slot, CT) -> - {_Key, {Slot, LSize, BinTerm}} = E, - Size = byte_size(BinTerm), - Size2 = ?POW(LSize-1), - Pad = <<0:(Size2-Size-?OHDSZ)/unit:8>>, - BinObject = [<<Next:32, Size:32, ?ACTIVE:32>>, BinTerm | Pad], - [Addr | L] = ?VGET(LSize, CT), - NCT = ?VSET(LSize, CT, [Addr+Size2 | [BinObject | L]]), - output_slot(Es, Addr, Slot, NCT); -output_slot([], Next, Slot, CT) -> - I = tuple_size(CT), - [Addr | L] = ?VGET(I, CT), - {Pos, _} = slot_position(Slot), - NoZeros = Pos - Addr, - BinObject = if - NoZeros > 100 -> - [dets_utils:make_zeros(NoZeros) | <<Next:32>>]; - true -> - <<0:NoZeros/unit:8,Next:32>> - end, - Size = NoZeros+4, - ?VSET(I, CT, [Addr+Size | [BinObject | L]]). - -%% Does not close Fd. -fsck_input(Head, Fd, Cntrs, _FileHeader) -> - %% The file is not compressed, so the object size cannot exceed - %% the filesize, for all objects. - MaxSz = case file:position(Fd, eof) of - {ok, Pos} -> - Pos; - _ -> - (1 bsl 32) - 1 - end, - State0 = fsck_read(?BASE, Fd, []), - fsck_input1(Head, State0, Fd, MaxSz, Cntrs). - -fsck_input1(Head, State, Fd, MaxSz, Cntrs) -> - fun(close) -> - ok; - (read) -> - case State of - done -> - end_of_input; - {done, L} -> - R = count_input(Cntrs, L, []), - {R, fsck_input1(Head, done, Fd, MaxSz, Cntrs)}; - {cont, L, Bin, Pos} -> - R = count_input(Cntrs, L, []), - FR = fsck_objs(Bin, Head#head.keypos, Head, []), - NewState = fsck_read(FR, Pos, Fd, MaxSz, Head), - {R, fsck_input1(Head, NewState, Fd, MaxSz, Cntrs)} - end - end. - -%% The ets table Cntrs is used for counting objects per size. -count_input(Cntrs, [[LogSz | B] | Ts], L) -> - count_object(Cntrs, LogSz), - count_input(Cntrs, Ts, [B | L]); -count_input(_Cntrs, [], L) -> - L. - -count_object(Cntrs, LogSz) -> - case catch ets:update_counter(Cntrs, LogSz, 1) of - N when is_integer(N) -> ok; - _Badarg -> true = ets:insert(Cntrs, {LogSz, 1}) - end. - -fsck_read(Pos, F, L) -> - case file:position(F, Pos) of - {ok, _} -> - read_more_bytes(<<>>, 0, Pos, F, L); - _Error -> - {done, L} - end. - -fsck_read({more, Bin, Sz, L}, Pos, F, MaxSz, Head) when Sz > MaxSz -> - FR = skip_bytes(Bin, ?BUMP, Head#head.keypos, Head, L), - fsck_read(FR, Pos, F, MaxSz, Head); -fsck_read({more, Bin, Sz, L}, Pos, F, _MaxSz, _Head) -> - read_more_bytes(Bin, Sz, Pos, F, L); -fsck_read({new, Skip, L}, Pos, F, _MaxSz, _Head) -> - NewPos = Pos + Skip, - fsck_read(NewPos, F, L). - -read_more_bytes(B, Min, Pos, F, L) -> - Max = if - Min < ?CHUNK_SIZE -> ?CHUNK_SIZE; - true -> Min - end, - case dets_utils:read_n(F, Max) of - eof -> - {done, L}; - Bin -> - NewPos = Pos + byte_size(Bin), - {cont, L, list_to_binary([B, Bin]), NewPos} - end. - -fsck_objs(Bin = <<_N:32, Sz:32, Status:32, Tail/binary>>, Kp, Head, L) -> - if - Status =:= ?ACTIVE -> - case Tail of - <<BinTerm:Sz/binary, Tail2/binary>> -> - case catch element(Kp, binary_to_term(BinTerm)) of - {'EXIT', _} -> - skip_bytes(Bin, ?BUMP, Kp, Head, L); - Key -> - LogSz = sz2pos(Sz+?OHDSZ), - Obj = make_object(Head, Key, LogSz, BinTerm), - NL = [[LogSz | Obj] | L], - Skip = ?POW(LogSz-1) - Sz - ?OHDSZ, - skip_bytes(Tail2, Skip, Kp, Head, NL) - end; - _ -> - {more, Bin, Sz, L} - end; - true -> - skip_bytes(Bin, ?BUMP, Kp, Head, L) - end; -fsck_objs(Bin, _Kp, _Head, L) -> - {more, Bin, 0, L}. - -%% Version 8 has to know about version 9. -make_object(Head, Key, _LogSz, BT) when Head#head.version =:= 9 -> - Slot = dets_v9:db_hash(Key, Head), - <<Slot:32, BT/binary>>; -make_object(Head, Key, LogSz, BT) -> - Slot = db_hash(Key, Head), - <<Slot:32, LogSz:8, BT/binary>>. - -%% Inlined. -skip_bytes(Bin, Skip, Kp, Head, L) -> - case Bin of - <<_:Skip/binary, Tail/binary>> -> - fsck_objs(Tail, Kp, Head, L); - _ -> - {new, Skip - byte_size(Bin), L} - end. - -%% -> {NewHead, ok} | throw({Head, Error}) -do_perform_save(H) -> - FL = dets_utils:get_freelists(H), - B = term_to_binary(FL), - Size = byte_size(B), - ?DEBUGF("size of freelist = ~p~n", [Size]), - ?DEBUGF("head.m = ~p~n", [H#head.m]), - ?DEBUGF("head.no_objects = ~p~n", [H#head.no_objects]), - - {ok, Pos} = dets_utils:position(H, eof), - H1 = H#head{freelists_p = Pos}, - W1 = {?FREELIST_POS, <<Pos:32>>}, - W2 = {Pos, [<<0:32, Size:32, ?FREE:32>>, B]}, - - W3 = {?D_POS, <<(H1#head.m):32, - (H1#head.next):32, - (H1#head.keypos):32, - (H1#head.no_objects):32, - (H1#head.n):32>>}, - {ClosedProperly, ClosedProperlyNeedCompacitng} = - case H1#head.hash_bif of - hash -> - {?CLOSED_PROPERLY2, ?CLOSED_PROPERLY2_NEED_COMPACTING}; - phash -> - {?CLOSED_PROPERLY_NEW_HASH, - ?CLOSED_PROPERLY_NEW_HASH_NEED_COMPACTING} - end, - W4 = - if - Size > 1000, Size > H1#head.no_objects -> - {?CLOSED_PROPERLY_POS, - <<ClosedProperlyNeedCompacitng:32>>}; - true -> - {?CLOSED_PROPERLY_POS, <<ClosedProperly:32>>} - end, - W5 = {?FILE_FORMAT_VERSION_POS, <<?FILE_FORMAT_VERSION:32>>}, - {H2, ok} = dets_utils:pwrite(H1, [W1,W2,W3,W4,W5]), - {ok, Pos2} = dets_utils:position(H2, eof), - ?DEBUGF("Writing file size ~p, eof at ~p~n", [Pos2+4, Pos2]), - dets_utils:pwrite(H2, [{Pos2, <<(Pos2 + 4):32>>}]). - -%% -> [term()] | throw({Head, Error}) -slot_objs(H, Slot) when Slot >= H#head.next -> - '$end_of_table'; -slot_objs(H, Slot) -> - {_Pos, Chain} = chain(H, Slot), - collect_chain(H, Chain). - -collect_chain(_H, 0) -> []; -collect_chain(H, Pos) -> - {Next, _Sz, Term} = prterm(H, Pos, ?ReadAhead), - [Term | collect_chain(H, Next)]. - -db_hash(Key, Head) -> - H = h(Key, Head#head.hash_bif), - Hash = H rem Head#head.m, - if - Hash < Head#head.n -> - H rem (Head#head.m2); % H rem (2 * m) - true -> - Hash - end. - -h(I, phash) -> erlang:phash(I, ?BIG) - 1; -h(I, HF) -> erlang:HF(I, ?BIG) - 1. %% stupid BIF has 1 counts. - -no_slots(_Head) -> - undefined. - -table_parameters(_Head) -> - undefined. - -%% Re-hashing a segment, starting with SlotStart. -%% -%% On the average, half of the objects of the chain are put into a new -%% chain. If the slot of the old chain is i, then the slot of the new -%% chain is i+m. -%% Note that the insertion of objects into the new chain is simplified -%% by the fact that the chains are not sorted on key, which means that -%% each moved object can be inserted first in the new chain. -%% (It is also a fact that the objects with the same key are not sorted.) -%% -%% -> {ok, Writes} | throw({Head, Error}) -re_hash(Head, SlotStart) -> - {SlotPos, _4} = slot_position(SlotStart), - {ok, Bin} = dets_utils:pread(Head, SlotPos, 4*?SEGSZ, 0), - {Read, Cs} = split_bin(SlotPos, Bin, [], []), - re_hash_read(Head, [], Read, Cs). - -split_bin(Pos, <<P:32, B/binary>>, R, Cs) -> - if - P =:= 0 -> - split_bin(Pos+4, B, R, Cs); - true -> - split_bin(Pos+4, B, [{P,?ReadAhead} | R], [[Pos] | Cs]) - end; -split_bin(_Pos, <<>>, R, Cs) -> - {R, Cs}. - -re_hash_read(Head, Cs, R, RCs) -> - {ok, Bins} = dets_utils:pread(R, Head), - re_hash_read(Head, R, RCs, Bins, Cs, [], []). - -re_hash_read(Head, [{Pos, Size} | Ps], [C | Cs], - [<<Next:32, Sz:32, _Status:32, Bin0/binary>> | Bins], - DoneCs, R, RCs) -> - case byte_size(Bin0) of - BinSz when BinSz >= Sz -> - case catch binary_to_term(Bin0) of - {'EXIT', _Error} -> - throw(dets_utils:corrupt_reason(Head, bad_object)); - Term -> - Key = element(Head#head.keypos, Term), - New = h(Key, Head#head.hash_bif) rem Head#head.m2, - NC = case New >= Head#head.m of - true -> [{Pos,New} | C]; - false -> [Pos | C] - end, - if - Next =:= 0 -> - NDoneCs = [NC | DoneCs], - re_hash_read(Head, Ps, Cs, Bins, NDoneCs, R, RCs); - true -> - NR = [{Next,?ReadAhead} | R], - NRCs = [NC | RCs], - re_hash_read(Head, Ps, Cs, Bins, DoneCs, NR, NRCs) - end - end; - BinSz when Size =:= BinSz+?OHDSZ -> - NR = [{Pos, Sz+?OHDSZ} | R], - re_hash_read(Head, Ps, Cs, Bins, DoneCs, NR, [C | RCs]); - _BinSz -> - throw({Head, {error, {premature_eof, Head#head.filename}}}) - end; -re_hash_read(Head, [], [], [], Cs, [], []) -> - re_hash_traverse_chains(Cs, Head, [], [], []); -re_hash_read(Head, [], [], [], Cs, R, RCs) -> - re_hash_read(Head, Cs, R, RCs). - -re_hash_traverse_chains([C | Cs], Head, Rs, Ns, Ws) -> - case re_hash_find_new(C, Rs, start, start) of - false -> - re_hash_traverse_chains(Cs, Head, Rs, Ns, Ws); - {NRs, FirstNew, LastNew} -> - LastInNew = case C of - [{_,_} | _] -> true; - _ -> false - end, - N = {FirstNew, LastNew, LastInNew}, - NWs = re_hash_link(C, start, start, start, Ws), - re_hash_traverse_chains(Cs, Head, NRs, [N | Ns], NWs) - end; -re_hash_traverse_chains([], Head, Rs, Ns, Ws) -> - {ok, Bins} = dets_utils:pread(Rs, Head), - {ok, insert_new(Rs, Bins, Ns, Ws)}. - -re_hash_find_new([{Pos,NewSlot} | C], R, start, start) -> - {SPos, _4} = slot_position(NewSlot), - re_hash_find_new(C, [{SPos,4} | R], Pos, Pos); -re_hash_find_new([{Pos,_SPos} | C], R, _FirstNew, LastNew) -> - re_hash_find_new(C, R, Pos, LastNew); -re_hash_find_new([_Pos | C], R, FirstNew, LastNew) -> - re_hash_find_new(C, R, FirstNew, LastNew); -re_hash_find_new([], _R, start, start) -> - false; -re_hash_find_new([], R, FirstNew, LastNew) -> - {R, FirstNew, LastNew}. - -re_hash_link([{Pos,_SPos} | C], LastOld, start, _LastInNew, Ws) -> - re_hash_link(C, LastOld, Pos, true, Ws); -re_hash_link([{Pos,_SPos} | C], LastOld, LastNew, false, Ws) -> - re_hash_link(C, LastOld, Pos, true, [{Pos,<<LastNew:32>>} | Ws]); -re_hash_link([{Pos,_SPos} | C], LastOld, _LastNew, LastInNew, Ws) -> - re_hash_link(C, LastOld, Pos, LastInNew, Ws); -re_hash_link([Pos | C], start, LastNew, true, Ws) -> - re_hash_link(C, Pos, LastNew, false, [{Pos,<<0:32>>} | Ws]); -re_hash_link([Pos | C], LastOld, LastNew, true, Ws) -> - re_hash_link(C, Pos, LastNew, false, [{Pos,<<LastOld:32>>} | Ws]); -re_hash_link([Pos | C], _LastOld, LastNew, LastInNew, Ws) -> - re_hash_link(C, Pos, LastNew, LastInNew, Ws); -re_hash_link([], _LastOld, _LastNew, _LastInNew, Ws) -> - Ws. - -insert_new([{NewSlotPos,_4} | Rs], [<<P:32>> = PB | Bins], [N | Ns], Ws) -> - {FirstNew, LastNew, LastInNew} = N, - Ws1 = case P of - 0 when LastInNew -> - Ws; - 0 -> - [{LastNew, <<0:32>>} | Ws]; - _ -> - [{LastNew, PB} | Ws] - end, - NWs = [{NewSlotPos, <<FirstNew:32>>} | Ws1], - insert_new(Rs, Bins, Ns, NWs); -insert_new([], [], [], Ws) -> - Ws. - -%% When writing the cache, a 'work list' is first created: -%% WorkList = [{Key, {Delete,Lookup,[Inserted]}}] -%% Delete = keep | delete -%% Lookup = skip | lookup -%% Inserted = {object(), No} -%% No = integer() -%% If No =< 0 then there will be -No instances of object() on the file -%% when the cache has been written. If No > 0 then No instances of -%% object() will be added to the file. -%% If Delete has the value 'delete', then all objects with the key Key -%% have been deleted. (This could be viewed as a shorthand for {Object,0} -%% for each object Object on the file not mentioned in some Inserted.) -%% If Lookup has the value 'lookup', all objects with the key Key will -%% be returned. -%% - -%% -> {NewHead, [LookedUpObject], pwrite_list()} | throw({NewHead, Error}) -write_cache(Head) -> - #head{cache = C, type = Type} = Head, - case dets_utils:is_empty_cache(C) of - true -> {Head, [], []}; - false -> - {NewC, _MaxInserts, PerKey} = dets_utils:reset_cache(C), - %% NoInsertedKeys is an upper limit on the number of new keys. - {WL, NoInsertedKeys} = make_wl(PerKey, Type), - Head1 = Head#head{cache = NewC}, - case may_grow(Head1, NoInsertedKeys, once) of - {Head2, ok} -> - eval_work_list(Head2, WL); - HeadError -> - throw(HeadError) - end - end. - -make_wl(PerKey, Type) -> - make_wl(PerKey, Type, [], 0). - -make_wl([{Key,L} | PerKey], Type, WL, Ins) -> - [Cs | I] = wl(L, Type), - make_wl(PerKey, Type, [{Key,Cs} | WL], Ins+I); -make_wl([], _Type, WL, Ins) -> - {WL, Ins}. - -wl(L, Type) -> - wl(L, Type, keep, skip, 0, []). - -wl([{_Seq, delete_key} | Cs], Type, _Del, Lookup, _I, _Objs) -> - wl(Cs, Type, delete, Lookup, 0, []); -wl([{_Seq, {delete_object, Object}} | Cs], Type, Del, Lookup, I, Objs) -> - NObjs = lists:keydelete(Object, 1, Objs), - wl(Cs, Type, Del, Lookup, I, [{Object,0} | NObjs]); -wl([{_Seq, {insert, Object}} | Cs], Type, _Del, Lookup, _I, _Objs) - when Type =:= set -> - wl(Cs, Type, delete, Lookup, 1, [{Object,-1}]); -wl([{_Seq, {insert, Object}} | Cs], Type, Del, Lookup, _I, Objs) -> - NObjs = - case lists:keyfind(Object, 1, Objs) of - {_, 0} -> - lists:keyreplace(Object, 1, Objs, {Object,-1}); - {_, _C} when Type =:= bag -> % C =:= 1; C =:= -1 - Objs; - {_, C} when C < 0 -> % when Type =:= duplicate_bag - lists:keyreplace(Object, 1, Objs, {Object,C-1}); - {_, C} -> % when C > 0, Type =:= duplicate_bag - lists:keyreplace(Object, 1, Objs, {Object,C+1}); - false when Del =:= delete -> - [{Object, -1} | Objs]; - false -> - [{Object, 1} | Objs] - end, - wl(Cs, Type, Del, Lookup, 1, NObjs); -wl([{_Seq, {lookup,_Pid}=Lookup} | Cs], Type, Del, _Lookup, I, Objs) -> - wl(Cs, Type, Del, Lookup, I, Objs); -wl([], _Type, Del, Lookup, I, Objs) -> - [{Del, Lookup, Objs} | I]. - -%% -> {NewHead, ok} | {NewHead, Error} -may_grow(Head, 0, once) -> - {Head, ok}; -may_grow(Head, _N, _How) when Head#head.fixed =/= false -> - {Head, ok}; -may_grow(#head{access = read}=Head, _N, _How) -> - {Head, ok}; -may_grow(Head, _N, _How) when Head#head.next >= ?MAXOBJS -> - {Head, ok}; -may_grow(Head, N, How) -> - Extra = erlang:min(2*?SEGSZ, Head#head.no_objects + N - Head#head.next), - case catch may_grow1(Head, Extra, How) of - {error, Reason} -> % alloc may throw error - {Head, {error, Reason}}; - Reply -> - Reply - end. - -may_grow1(Head, Extra, many_times) when Extra > ?SEGSZ -> - Reply = grow(Head, 1, undefined), - self() ! ?DETS_CALL(self(), may_grow), - Reply; -may_grow1(Head, Extra, _How) -> - grow(Head, Extra, undefined). - -%% -> {Head, ok} | throw({Head, Error}) -grow(Head, Extra, _SegZero) when Extra =< 0 -> - {Head, ok}; -grow(Head, Extra, undefined) -> - grow(Head, Extra, seg_zero()); -grow(Head, Extra, SegZero) -> - #head{n = N, next = Next, m = M} = Head, - SegNum = ?SLOT2SEG(Next), - {Head0, Ws1} = allocate_segment(Head, SegZero, SegNum), - {Head1, ok} = dets_utils:pwrite(Head0, Ws1), - %% If re_hash fails, segp_cache has been called, but it does not matter. - {ok, Ws2} = re_hash(Head1, N), - {Head2, ok} = dets_utils:pwrite(Head1, Ws2), - NewHead = - if - N + ?SEGSZ =:= M -> - Head2#head{n = 0, next = Next + ?SEGSZ, m = 2 * M, m2 = 4 * M}; - true -> - Head2#head{n = N + ?SEGSZ, next = Next + ?SEGSZ} - end, - grow(NewHead, Extra - ?SEGSZ, SegZero). - -seg_zero() -> - <<0:(4*?SEGSZ)/unit:8>>. - -find_object(Head, Object) -> - Key = element(Head#head.keypos, Object), - Slot = db_hash(Key, Head), - find_object(Head, Object, Slot). - -find_object(H, _Obj, Slot) when Slot >= H#head.next -> - false; -find_object(H, Obj, Slot) -> - {_Pos, Chain} = chain(H, Slot), - case catch find_obj(H, Obj, Chain) of - {ok, Pos} -> - {ok, Pos}; - _Else -> - false - end. - -find_obj(H, Obj, Pos) when Pos > 0 -> - {Next, _Sz, Term} = prterm(H, Pos, ?ReadAhead), - if - Term == Obj -> - {ok, Pos}; - true -> - find_obj(H, Obj, Next) - end. - -%% Given, a slot, return the {Pos, Chain} in the file where the -%% objects hashed to this slot reside. Pos is the position in the -%% file where the chain pointer is written and Chain is the position -%% in the file where the first object resides. -chain(Head, Slot) -> - Pos = ?SEGADDR(?SLOT2SEG(Slot)), - Segment = get_segp(Pos), - FinalPos = Segment + (4 * ?REM2(Slot, ?SEGSZ)), - {ok, <<Chain:32>>} = dets_utils:pread(Head, FinalPos, 4, 0), - {FinalPos, Chain}. - -%%% -%%% Cache routines depending on the dets file format. -%%% - -%% -> {Head, [LookedUpObject], pwrite_list()} | throw({Head, Error}) -eval_work_list(Head, WorkLists) -> - SWLs = tag_with_slot(WorkLists, Head, []), - P1 = dets_utils:family(SWLs), - {PerSlot, SlotPositions} = remove_slot_tag(P1, [], []), - {ok, Bins} = dets_utils:pread(SlotPositions, Head), - first_object(PerSlot, SlotPositions, Bins, Head, [], [], [], []). - -tag_with_slot([{K,_} = WL | WLs], Head, L) -> - tag_with_slot(WLs, Head, [{db_hash(K, Head), WL} | L]); -tag_with_slot([], _Head, L) -> - L. - -remove_slot_tag([{S,SWLs} | SSWLs], Ls, SPs) -> - remove_slot_tag(SSWLs, [SWLs | Ls], [slot_position(S) | SPs]); -remove_slot_tag([], Ls, SPs) -> - {Ls, SPs}. - -%% The initial chain pointers and the first object in each chain are -%% read "in parallel", that is, with one call to file:pread/2 (two -%% calls altogether). The following chain objects are read one by -%% one. This is a compromise: if the chains are long and threads are -%% active, it would be faster to keep a state for each chain and read -%% the objects of the chains in parallel, but the overhead would be -%% quite substantial. - -first_object([WorkLists | SPs], [{P1,_4} | Ss], [<<P2:32>> | Bs], Head, - ObjsToRead, ToRead, Ls, LU) when P2 =:= 0 -> - L0 = [{old,P1}], - {L, NLU} = eval_slot(Head, ?ReadAhead, P2, WorkLists, L0, LU), - first_object(SPs, Ss, Bs, Head, ObjsToRead, ToRead, [L | Ls], NLU); -first_object([WorkLists | SPs], [{P1,_4} | Ss], [<<P2:32>> | Bs], Head, - ObjsToRead, ToRead, Ls, LU) -> - E = {P1,P2,WorkLists}, - first_object(SPs, Ss, Bs, Head, - [E | ObjsToRead], [{P2, ?ReadAhead} | ToRead], Ls, LU); -first_object([], [], [], Head, ObjsToRead, ToRead, Ls, LU) -> - {ok, Bins} = dets_utils:pread(ToRead, Head), - case catch eval_first(Bins, ObjsToRead, Head, Ls, LU) of - {ok, NLs, NLU} -> - case create_writes(NLs, Head, [], 0) of - {Head1, [], 0} -> - {Head1, NLU, []}; - {Head1, Ws, No} -> - {NewHead, Ws2} = update_no_objects(Head1, Ws, No), - {NewHead, NLU, Ws2} - end; - _Error -> - throw(dets_utils:corrupt_reason(Head, bad_object)) - end. - -%% Update no_objects on the file too, if the number of segments that -%% dets:fsck/6 use for estimate has changed. -update_no_objects(Head, Ws, 0) -> {Head, Ws}; -update_no_objects(Head, Ws, Delta) -> - No = Head#head.no_objects, - NewNo = No + Delta, - NWs = - if - NewNo > ?MAXOBJS -> - Ws; - ?SLOT2SEG(No) =:= ?SLOT2SEG(NewNo) -> - Ws; - true -> - [{?NO_OBJECTS_POS, <<NewNo:32>>} | Ws] - end, - {Head#head{no_objects = NewNo}, NWs}. - -eval_first([<<Next:32, Sz:32, _Status:32, Bin/binary>> | Bins], - [SP | SPs], Head, Ls, LU) -> - {P1, P2, WLs} = SP, - L0 = [{old,P1}], - case byte_size(Bin) of - BinSz when BinSz >= Sz -> - Term = binary_to_term(Bin), - Key = element(Head#head.keypos, Term), - {L, NLU} = find_key(Head, P2, Next, Sz, Term, Key, WLs, L0, LU), - eval_first(Bins, SPs, Head, [L | Ls], NLU); - _BinSz -> - {L, NLU} = eval_slot(Head, Sz+?OHDSZ, P2, WLs, L0, LU), - eval_first(Bins, SPs, Head, [L | Ls], NLU) - end; -eval_first([], [], _Head, Ls, LU) -> - {ok, Ls, LU}. - -eval_slot(_Head, _TrySize, _Pos=0, [], L, LU) -> - {L, LU}; -eval_slot(Head, _TrySize, Pos=0, [WL | WLs], L, LU) -> - {_Key, {_Delete, LookUp, Objects}} = WL, - {NL, NLU} = end_of_key(Objects, LookUp, L, []), - eval_slot(Head, ?ReadAhead, Pos, WLs, NL, NLU++LU); -eval_slot(Head, TrySize, Pos, WLs, L, LU) -> - {NextPos, Size, Term} = prterm(Head, Pos, TrySize), - Key = element(Head#head.keypos, Term), - find_key(Head, Pos, NextPos, Size, Term, Key, WLs, L, LU). - -find_key(Head, Pos, NextPos, Size, Term, Key, WLs, L, LU) -> - case lists:keyfind(Key, 1, WLs) of - {_, {Delete, LookUp, Objects}} = WL -> - NWLs = lists:delete(WL, WLs), - {NewObjects, NL, LUK} = eval_object(Size, Term, Delete, LookUp, - Objects, Head, Pos, L, []), - eval_key(Key, Delete, LookUp, NewObjects, Head, NextPos, - NWLs, NL, LU, LUK); - false -> - L0 = [{old,Pos} | L], - eval_slot(Head, ?ReadAhead, NextPos, WLs, L0, LU) - end. - -eval_key(_Key, _Delete, Lookup, _Objects, Head, Pos, WLs, L, LU, LUK) - when Head#head.type =:= set -> - NLU = case Lookup of - {lookup, Pid} -> [{Pid,LUK} | LU]; - skip -> LU - end, - eval_slot(Head, ?ReadAhead, Pos, WLs, L, NLU); -eval_key(_Key, _Delete, LookUp, Objects, Head, Pos, WLs, L, LU, LUK) - when Pos =:= 0 -> - {NL, NLU} = end_of_key(Objects, LookUp, L, LUK), - eval_slot(Head, ?ReadAhead, Pos, WLs, NL, NLU++LU); -eval_key(Key, Delete, LookUp, Objects, Head, Pos, WLs, L, LU, LUK) -> - {NextPos, Size, Term} = prterm(Head, Pos, ?ReadAhead), - case element(Head#head.keypos, Term) of - Key -> - {NewObjects, NL, LUK1} = - eval_object(Size, Term, Delete, LookUp,Objects,Head,Pos,L,LUK), - eval_key(Key, Delete, LookUp, NewObjects, Head, NextPos, WLs, - NL, LU, LUK1); - Key2 -> - {L1, NLU} = end_of_key(Objects, LookUp, L, LUK), - find_key(Head, Pos, NextPos, Size, Term, Key2, WLs, L1, NLU++LU) - end. - -%% All objects in Objects have the key Key. -eval_object(Size, Term, Delete, LookUp, Objects, Head, Pos, L, LU) -> - Type = Head#head.type, - case lists:keyfind(Term, 1, Objects) of - {_Object, N} when N =:= 0 -> - L1 = [{delete,Pos,Size} | L], - {Objects, L1, LU}; - {_Object, N} when N < 0, Type =:= set -> - L1 = [{old,Pos} | L], - wl_lookup(LookUp, Objects, Term, L1, LU); - {Object, _N} when Type =:= bag -> % when N =:= 1; N =:= -1 - L1 = [{old,Pos} | L], - Objects1 = lists:keydelete(Object, 1, Objects), - wl_lookup(LookUp, Objects1, Term, L1, LU); - {Object, N} when N < 0, Type =:= duplicate_bag -> - L1 = [{old,Pos} | L], - Objects1 = lists:keyreplace(Object, 1, Objects, {Object,N+1}), - wl_lookup(LookUp, Objects1, Term, L1, LU); - {_Object, N} when N > 0, Type =:= duplicate_bag -> - L1 = [{old,Pos} | L], - wl_lookup(LookUp, Objects, Term, L1, LU); - false when Type =:= set, Delete =:= delete -> - case lists:keyfind(-1, 2, Objects) of - false -> % no inserted object, perhaps deleted objects - L1 = [{delete,Pos,Size} | L], - {[], L1, LU}; - {Term2, -1} -> - Bin2 = term_to_binary(Term2), - NSize = byte_size(Bin2), - Overwrite = - if - NSize =:= Size -> - true; - true -> - SizePos = sz2pos(Size+?OHDSZ), - NSizePos = sz2pos(NSize+?OHDSZ), - SizePos =:= NSizePos - end, - E = if - Overwrite -> - {overwrite,Bin2,Pos}; - true -> - {replace,Bin2,Pos,Size} - end, - wl_lookup(LookUp, [], Term2, [E | L], LU) - end; - false when Delete =:= delete -> - L1 = [{delete,Pos,Size} | L], - {Objects, L1, LU}; - false -> - L1 = [{old,Pos} | L], - wl_lookup(LookUp, Objects, Term, L1, LU) - end. - -%% Inlined. -wl_lookup({lookup,_}, Objects, Term, L, LU) -> - {Objects, L, [Term | LU]}; -wl_lookup(skip, Objects, _Term, L, LU) -> - {Objects, L, LU}. - -end_of_key([{Object,N0} | Objs], LookUp, L, LU) when N0 =/= 0 -> - N = abs(N0), - NL = [{insert,N,term_to_binary(Object)} | L], - NLU = case LookUp of - {lookup, _} -> - lists:duplicate(N, Object) ++ LU; - skip -> - LU - end, - end_of_key(Objs, LookUp, NL, NLU); -end_of_key([_ | Objects], LookUp, L, LU) -> - end_of_key(Objects, LookUp, L, LU); -end_of_key([], {lookup,Pid}, L, LU) -> - {L, [{Pid,LU}]}; -end_of_key([], skip, L, LU) -> - {L, LU}. - -create_writes([L | Ls], H, Ws, No) -> - {NH, NWs, NNo} = create_writes(L, H, Ws, No, 0, true), - create_writes(Ls, NH, NWs, NNo); -create_writes([], H, Ws, No) -> - {H, lists:reverse(Ws), No}. - -create_writes([{old,Pos} | L], H, Ws, No, _Next, true) -> - create_writes(L, H, Ws, No, Pos, true); -create_writes([{old,Pos} | L], H, Ws, No, Next, false) -> - W = {Pos, <<Next:32>>}, - create_writes(L, H, [W | Ws], No, Pos, true); -create_writes([{insert,N,Bin} | L], H, Ws, No, Next, _NextIsOld) -> - {NH, NWs, Pos} = create_inserts(N, H, Ws, Next, byte_size(Bin), Bin), - create_writes(L, NH, NWs, No+N, Pos, false); -create_writes([{overwrite,Bin,Pos} | L], H, Ws, No, Next, _) -> - Size = byte_size(Bin), - W = {Pos, [<<Next:32, Size:32, ?ACTIVE:32>>, Bin]}, - create_writes(L, H, [W | Ws], No, Pos, true); -create_writes([{replace,Bin,Pos,OSize} | L], H, Ws, No, Next, _) -> - Size = byte_size(Bin), - {H1, _} = dets_utils:free(H, Pos, OSize+?OHDSZ), - {NH, NewPos, _} = dets_utils:alloc(H1, ?OHDSZ + Size), - W1 = {NewPos, [<<Next:32, Size:32, ?ACTIVE:32>>, Bin]}, - NWs = if - Pos =:= NewPos -> - [W1 | Ws]; - true -> - W2 = {Pos+?STATUS_POS, <<?FREE:32>>}, - [W1,W2 | Ws] - end, - create_writes(L, NH, NWs, No, NewPos, false); -create_writes([{delete,Pos,Size} | L], H, Ws, No, Next, _) -> - {NH, _} = dets_utils:free(H, Pos, Size+?OHDSZ), - NWs = [{Pos+?STATUS_POS,<<?FREE:32>>} | Ws], - create_writes(L, NH, NWs, No-1, Next, false); -create_writes([], H, Ws, No, _Next, _NextIsOld) -> - {H, Ws, No}. - -create_inserts(0, H, Ws, Next, _Size, _Bin) -> - {H, Ws, Next}; -create_inserts(N, H, Ws, Next, Size, Bin) -> - {NH, Pos, _} = dets_utils:alloc(H, ?OHDSZ + Size), - W = {Pos, [<<Next:32, Size:32, ?ACTIVE:32>>, Bin]}, - create_inserts(N-1, NH, [W | Ws], Pos, Size, Bin). - -slot_position(S) -> - Pos = ?SEGADDR(?SLOT2SEG(S)), - Segment = get_segp(Pos), - FinalPos = Segment + (4 * ?REM2(S, ?SEGSZ)), - {FinalPos, 4}. - -%% Twice the size of a segment due to the bug in sz2pos/1. Inlined. -actual_seg_size() -> - ?POW(sz2pos(?SEGSZ*4)-1). - -segp_cache(Pos, Segment) -> - put(Pos, Segment). - -%% Inlined. -get_segp(Pos) -> - get(Pos). - -%% Bug: If Sz0 is equal to 2**k for some k, then 2**(k+1) bytes are -%% allocated (wasting 2**k bytes). -sz2pos(N) -> - 1 + dets_utils:log2(N+1). - -scan_objs(_Head, Bin, From, To, L, Ts, R, _Type) -> - scan_objs(Bin, From, To, L, Ts, R). - -scan_objs(Bin, From, To, L, Ts, -1) -> - {stop, Bin, From, To, L, Ts}; -scan_objs(B = <<_N:32, Sz:32, St:32, T/binary>>, From, To, L, Ts, R) -> - if - St =:= ?ACTIVE; - St =:= ?FREE -> % deleted after scanning started - case T of - <<BinTerm:Sz/binary, T2/binary>> -> - NTs = [BinTerm | Ts], - OSz = Sz + ?OHDSZ, - Skip = ?POW(sz2pos(OSz)-1) - OSz, - F2 = From + OSz, - NR = if - R < 0 -> - R + 1; - true -> - R + OSz + Skip - end, - scan_skip(T2, F2, To, Skip, L, NTs, NR); - _ -> - {more, From, To, L, Ts, R, Sz+?OHDSZ} - end; - true -> % a segment - scan_skip(B, From, To, actual_seg_size(), L, Ts, R) - end; -scan_objs(_B, From, To, L, Ts, R) -> - {more, From, To, L, Ts, R, 0}. - -scan_skip(Bin, From, To, Skip, L, Ts, R) when From + Skip < To -> - SkipPos = From + Skip, - case Bin of - <<_:Skip/binary, Tail/binary>> -> - scan_objs(Tail, SkipPos, To, L, Ts, R); - _ -> - {more, SkipPos, To, L, Ts, R, 0} - end; -scan_skip(Bin, From, To, Skip, L, Ts, R) when From + Skip =:= To -> - scan_next_allocated(Bin, From, To, L, Ts, R); -scan_skip(_Bin, From, _To, Skip, L, Ts, R) -> % when From + Skip > _To - From1 = From + Skip, - {more, From1, From1, L, Ts, R, 0}. - -scan_next_allocated(_Bin, _From, To, <<>>=L, Ts, R) -> - {more, To, To, L, Ts, R, 0}; -scan_next_allocated(Bin, From0, _To, <<From:32, To:32, L/binary>>, Ts, R) -> - Skip = From - From0, - scan_skip(Bin, From0, To, Skip, L, Ts, R). - -%% Read term from file at position Pos -prterm(Head, Pos, ReadAhead) -> - Res = dets_utils:pread(Head, Pos, ?OHDSZ, ReadAhead), - ?DEBUGF("file:pread(~tp, ~p, ?) -> ~p~n", [Head#head.filename, Pos, Res]), - {ok, <<Next:32, Sz:32, _Status:32, Bin0/binary>>} = Res, - ?DEBUGF("{Next, Sz} = ~p~n", [{Next, Sz}]), - Bin = case byte_size(Bin0) of - Actual when Actual >= Sz -> - Bin0; - _ -> - {ok, Bin1} = dets_utils:pread(Head, Pos + ?OHDSZ, Sz, 0), - Bin1 - end, - Term = binary_to_term(Bin), - {Next, Sz, Term}. - -%%%%%%%%%%%%%%%%% DEBUG functions %%%%%%%%%%%%%%%% - -file_info(FH) -> - #fileheader{closed_properly = CP, keypos = Kp, - m = M, next = Next, n = N, version = Version, - type = Type, no_objects = NoObjects} - = FH, - if - CP =:= 0 -> - {error, not_closed}; - FH#fileheader.cookie =/= ?MAGIC -> - {error, not_a_dets_file}; - FH#fileheader.version =/= ?FILE_FORMAT_VERSION -> - {error, bad_version}; - true -> - {ok, [{closed_properly,CP},{keypos,Kp},{m, M}, - {n,N},{next,Next},{no_objects,NoObjects}, - {type,Type},{version,Version}]} - end. - -v_segments(H) -> - v_segments(H, 0). - -v_segments(_H, ?SEGARRSZ) -> - done; -v_segments(H, SegNo) -> - Seg = dets_utils:read_4(H#head.fptr, ?SEGADDR(SegNo)), - if - Seg =:= 0 -> - done; - true -> - io:format("SEGMENT ~w ", [SegNo]), - io:format("At position ~w~n", [Seg]), - v_segment(H, SegNo, Seg, 0), - v_segments(H, SegNo+1) - end. - -v_segment(_H, _, _SegPos, ?SEGSZ) -> - done; -v_segment(H, SegNo, SegPos, SegSlot) -> - Slot = SegSlot + (SegNo * ?SEGSZ), - Chain = dets_utils:read_4(H#head.fptr, SegPos + (4 * SegSlot)), - if - Chain =:= 0 -> %% don't print empty chains - true; - true -> - io:format(" <~p>~p: [",[SegPos + (4 * SegSlot), Slot]), - print_chain(H, Chain) - end, - v_segment(H, SegNo, SegPos, SegSlot+1). - -print_chain(_H, 0) -> - io:format("] \n", []); -print_chain(H, Pos) -> - {ok, _} = file:position(H#head.fptr, Pos), - case rterm(H#head.fptr) of - {ok, 0, _Sz, Term} -> - io:format("<~p>~p] \n",[Pos, Term]); - {ok, Next, _Sz, Term} -> - io:format("<~p>~p, ", [Pos, Term]), - print_chain(H, Next); - Other -> - io:format("~nERROR ~p~n", [Other]) - end. - -%% Can't be used at the bucket level!!!! -%% Only when we go down a chain -rterm(F) -> - case catch rterm2(F) of - {'EXIT', Reason} -> %% truncated DAT file - dets_utils:vformat("** dets: Corrupt or truncated dets file~n", - []), - {error, Reason}; - Other -> - Other - end. - -rterm2(F) -> - {ok, <<Next:32, Sz:32, _:32>>} = file:read(F, ?OHDSZ), - {ok, Bin} = file:read(F, Sz), - Term = binary_to_term(Bin), - {ok, Next, Sz, Term}. - - |