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author | Erlang/OTP <otp@erlang.org> | 2009-11-20 14:54:40 +0000 |
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committer | Erlang/OTP <otp@erlang.org> | 2009-11-20 14:54:40 +0000 |
commit | 84adefa331c4159d432d22840663c38f155cd4c1 (patch) | |
tree | bff9a9c66adda4df2106dfd0e5c053ab182a12bd /lib/stdlib/src/dets_v9.erl | |
download | otp-84adefa331c4159d432d22840663c38f155cd4c1.tar.gz otp-84adefa331c4159d432d22840663c38f155cd4c1.tar.bz2 otp-84adefa331c4159d432d22840663c38f155cd4c1.zip |
The R13B03 release.OTP_R13B03
Diffstat (limited to 'lib/stdlib/src/dets_v9.erl')
-rw-r--r-- | lib/stdlib/src/dets_v9.erl | 2761 |
1 files changed, 2761 insertions, 0 deletions
diff --git a/lib/stdlib/src/dets_v9.erl b/lib/stdlib/src/dets_v9.erl new file mode 100644 index 0000000000..53238e962f --- /dev/null +++ b/lib/stdlib/src/dets_v9.erl @@ -0,0 +1,2761 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2001-2009. All Rights Reserved. +%% +%% The contents of this file are subject to the Erlang Public License, +%% Version 1.1, (the "License"); you may not use this file except in +%% compliance with the License. You should have received a copy of the +%% Erlang Public License along with this software. If not, it can be +%% retrieved online at http://www.erlang.org/. +%% +%% Software distributed under the License is distributed on an "AS IS" +%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See +%% the License for the specific language governing rights and limitations +%% under the License. +%% +%% %CopyrightEnd% +%% +-module(dets_v9). + +%% Dets files, implementation part. This module handles version 9. +%% To be called from dets.erl only. + +-export([constants/0, mark_dirty/1, read_file_header/2, + check_file_header/2, do_perform_save/1, initiate_file/11, + prep_table_copy/9, init_freelist/2, fsck_input/4, + bulk_input/3, output_objs/4, bchunk_init/2, + try_bchunk_header/2, compact_init/3, read_bchunks/2, + write_cache/1, may_grow/3, find_object/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]). + +-compile({inline, [{max_objsize,1},{maxobjsize,1}]}). +-compile({inline, [{write_segment_file,6}]}). +-compile({inline, [{sz2pos,1},{adjsz,1}]}). +-compile({inline, [{skip_bytes,6},{make_object,4}]}). +-compile({inline, [{segp_cache,2},{get_segp,1},{get_arrpart,1}]}). +-compile({inline, [{h,2}]}). + +-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 NoKeys +%% 4 MinNoSlots +%% 4 MaxNoSlots +%% 4 HashMethod +%% 4 N +%% --- +%% 256 Version 9(a): Reserved for future versions. Initially zeros. +%% Version 9(b) has instead: +%% 112 28 counters for the buddy system sizes 2^4 to 2^31. +%% 144 Reserved for future versions. Initially zeros. +%% Version 9(c) has instead: +%% 112 28 counters for the buddy system sizes (as for 9(b)). +%% 16 MD5-sum for the 44 plus 112 bytes before the MD5-sum. +%% (FreelistsPointer, Cookie and ClosedProperly are not digested.) +%% 128 Reserved for future versions. Initially zeros. +%% --- +%% ------------------ end of file header +%% 4*256 SegmentArray Pointers. +%% ------------------ This is BASE. +%% 4*512 SegmentArray Part 1 +%% ... More SegmentArray Parts +%% 8*256 First segment +%% ??? Objects (free and alive) +%% 4*512 Further SegmentArray Part. +%% ??? Objects (free and alive) +%% 8*256 Further segment. +%% ??? Objects (free and alive) +%% ... more objects, segment array parts, and segments ... +%% ----------------------------- +%% ??? Free lists +%% ----------------------------- +%% 4 File size, in bytes. + +%% 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 +%% collection of objects resides. Each collection has the following +%% layout: +%% +%% bytes decsription +%% -------------------- +%% 4 Size of the area allocated for the collection (8+Sz) +%% 4 Status (FREE or ACTIVE). These two are the Object Header. +%% Sz A binary containing the objects per key, sorted on key. +%% +%% When repairing or converting a file, the status field is used. +%% +%% The binary containing the objects per key of a table of type 'set' +%% has the following layout: +%% +%% bytes decsription +%% -------------------- +%% 4 Size of the object of the first key (4+OSz1) +%% OSz1 The object of the first key +%% ... +%% 4 Size of the object of the ith key (4+OSzi) +%% OSzi The object of the ith key +%% +%% The binary containing the objects per key of a table of type 'bag' +%% or 'duplicate_bag' has the following layout: +%% +%% bytes decsription +%% ---------------------- +%% 4 Size of the objects of the first key (4 + OSz1_1+...+OSz1_j+...) +%% 4 Size of the first object of the first key (4+OSz1_1) +%% OSz1_1 The first object of the first key +%% ... +%% 4 Size of the jth object of the first key (4+OSz1_j) +%% OSz1_j The jth object of the first key +%% ... +%% 4 Size of the objects of the ith key (4 + OSzi_1+...+OSzi_k+...) +%% 4 Size of the first object of the ith key (4+OSzi_1) +%% OSzi_1 The first object of the ith key +%% ... +%% 4 Size of the kth object of the ith key (4+OSzi_k) +%% OSzi_k The kth object of the ith key +%% ... +%% +%% The objects of a key are placed in time order, that is, the older +%% objects come first. If a new object is inserted, it is inserted +%% last. +%% +%% +%% +%%|---------------| +%%| head | +%%| | +%%| | +%%|_______________| +%%| |--| +%%|___part ptr 1__| | +%%| | | segarr part 1 +%%|___part ptr 2__| V______________| +%%| | | p1 | +%%| | |______________|--| +%%| .... | | p2 | | +%% (256) |______________| | +%% | | | +%% | .... | | segment 1 +%% | (512) | V __slot 0 ____| +%% | size | +%% | pointer |--| +%% |___slot 1 ____| | +%% | | | +%% | .... | | objects in slot 0 +%% (256) V segment 1 +%% |___________| +%% | size | +%% |___________| +%% | status | +%% |___________| +%% | | +%% | object | +%% | collec. | +%% |___________| + +%%% +%%% File header +%%% + +-define(RESERVED, 128). % Reserved for future use. + +-define(COLL_CNTRS, (28*4)). % Counters for the buddy system. +-define(MD5SZ, 16). + +-define(HEADSZ, + 56+?COLL_CNTRS+?MD5SZ). % The size of the file header, in bytes, + % not including the reserved part. +-define(HEADEND, (?HEADSZ+?RESERVED)). + % End of header and reserved area. +-define(SEGSZ, 512). % Size of a segment, in words. SZOBJP*SEGSZP. +-define(SEGSZP, 256). % Size of a segment, in number of pointers. +-define(SEGSZP_LOG2, 8). +-define(SEGOBJSZ, (4 * ?SZOBJP)). +-define(SEGPARTSZ, 512). % Size of segment array part, in words. +-define(SEGPARTSZ_LOG2, 9). +-define(SEGARRSZ, 256). % Maximal number of segment array parts.. +-define(SEGARRADDR(PartN), (?HEADEND + (4 * (PartN)))). +-define(SEGPARTADDR(P,SegN), ((P) + (4 * ?REM2(SegN, ?SEGPARTSZ)))). +-define(BASE, ?SEGARRADDR(?SEGARRSZ)). +-define(MAXSLOTS, (?SEGARRSZ * ?SEGPARTSZ * ?SEGSZP)). + +-define(SLOT2SEG(S), ((S) bsr ?SEGSZP_LOG2)). +-define(SEG2SEGARRPART(S), ((S) bsr ?SEGPARTSZ_LOG2)). + +-define(PHASH, 0). +-define(PHASH2, 1). + +%% BIG is used for hashing. BIG must be greater than the maximum +%% number of slots, currently 32 M (MAXSLOTS). +-define(BIG, 16#3ffffff). % 64 M + +%% Hard coded positions into the file header: +-define(FREELIST_POS, 0). +-define(CLOSED_PROPERLY_POS, 8). +-define(D_POS, 20). + +%%% Dets file versions up to 8 are handled in dets_v8. This module +%%% handles version 9, introduced in R8. +%%% +%%% Version 9(a) tables have 256 reserved bytes in the file header, +%%% all initialized to zero. +%%% Version 9(b) tables use the first 112 of these bytes for storing +%%% number of objects for each size of the buddy system. An empty 9(b) +%%% table cannot be distinguished from an empty 9(a) table. +%%% 9(c) has an MD5-sum for the file header. + +-define(FILE_FORMAT_VERSION, 9). + +-define(NOT_PROPERLY_CLOSED,0). +-define(CLOSED_PROPERLY,1). + +%% Size of object pointer, in words. SEGSZ = SZOBJP * SEGSZP. +-define(SZOBJP, 2). + +-define(OHDSZ, 8). % The size of the object header, in bytes. +-define(STATUS_POS, 4). % Position of the status field. + +-define(OHDSZ_v8, 12). % The size of the version 8 object header. + +%% The size of each object is a multiple of 16. +%% BUMP is used when repairing files. +-define(BUMP, 16). + +%%% '$hash' is the value of HASH_PARMS in R8, '$hash2' is the value in R9. +%%% +%%% The fields of the ?HASH_PARMS records are the same, but having +%%% different tags makes bchunk_init on R8 nodes reject data from R9 +%%% nodes, and vice versa. This is overkill, and due to an oversight. +%%% What should have been done in R8 was to check the hash method, not +%%% only the type of the table and the key position. R8 nodes cannot +%%% handle the phash2 method. +-define(HASH_PARMS, '$hash2'). + +-define(BCHUNK_FORMAT_VERSION, 1). + +-record(?HASH_PARMS, { + file_format_version, + bchunk_format_version, + file, type, keypos, hash_method, + n,m,next, + min,max, + no_objects,no_keys, + no_colls % [{LogSz,NoColls}], NoColls >= 0 + }). + +-define(ACTUAL_SEG_SIZE, (?SEGSZ*4)). + +-define(MAXBUD, 32). + +%%-define(DEBUGF(X,Y), io:format(X, Y)). +-define(DEBUGF(X,Y), void). + +%% {Bump} +constants() -> + {?BUMP, ?BASE}. + +%% -> ok | throw({NewHead,Error}) +mark_dirty(Head) -> + Dirty = [{?CLOSED_PROPERLY_POS, <<?NOT_PROPERLY_CLOSED:32>>}], + dets_utils:pwrite(Head, Dirty), + dets_utils:sync(Head), + dets_utils:position(Head, Head#head.freelists_p), + dets_utils:truncate(Head, cur). + +%% -> {ok, head()} | throw(Error) | throw(badarg) +prep_table_copy(Fd, Tab, Fname, Type, Kp, Ram, CacheSz, Auto, Parms) -> + case Parms of + #?HASH_PARMS{file_format_version = ?FILE_FORMAT_VERSION, + bchunk_format_version = ?BCHUNK_FORMAT_VERSION, + n = N, m = M, next = Next, + min = Min, max = Max, + hash_method = HashMethodCode, + no_objects = NoObjects, no_keys = NoKeys, + no_colls = _NoColls} + when is_integer(N), is_integer(M), is_integer(Next), + is_integer(Min), is_integer(Max), + is_integer(NoObjects), is_integer(NoKeys), + NoObjects >= NoKeys -> + HashMethod = code_to_hash_method(HashMethodCode), + case hash_invars(N, M, Next, Min, Max) of + false -> + throw(badarg); + true -> + init_file(Fd, Tab, Fname, Type, Kp, Min, Max, Ram, + CacheSz, Auto, false, M, N, Next, HashMethod, + NoObjects, NoKeys) + end; + _ -> + throw(badarg) + end. + +%% -> {ok, head()} | throw(Error) +%% The File header and the SegmentArray Pointers are written here. +%% SegmentArray Parts are also written, but the segments are are not +%% initialized on file unless DoInitSegments is 'true'. (When +%% initializing a file by calling init_table, some time is saved by +%% not writing the segments twice.) +initiate_file(Fd, Tab, Fname, Type, Kp, MinSlots0, MaxSlots0, + Ram, CacheSz, Auto, DoInitSegments) -> + MaxSlots1 = erlang:min(MaxSlots0, ?MAXSLOTS), + MinSlots1 = erlang:min(MinSlots0, MaxSlots1), + MinSlots = slots2(MinSlots1), + MaxSlots = slots2(MaxSlots1), + M = Next = MinSlots, + N = 0, + init_file(Fd, Tab, Fname, Type, Kp, MinSlots, MaxSlots, Ram, CacheSz, + Auto, DoInitSegments, M, N, Next, phash2, 0, 0). + +init_file(Fd, Tab, Fname, Type, Kp, MinSlots, MaxSlots, Ram, CacheSz, + Auto, DoInitSegments, M, N, Next, HashMethod, NoObjects, NoKeys) -> + Ftab = dets_utils:init_alloc(?BASE), + + Head0 = #head{ + m = M, + m2 = M * 2, + next = Next, + fptr = Fd, + no_objects = NoObjects, + no_keys = NoKeys, + maxobjsize = 0, + n = N, + type = Type, + update_mode = dirty, + freelists = Ftab, + no_collections = orddict:new(), + auto_save = Auto, + hash_bif = HashMethod, + has_md5 = true, + keypos = Kp, + min_no_slots = MinSlots, + max_no_slots = MaxSlots, + + ram_file = Ram, + filename = Fname, + name = Tab, + cache = dets_utils:new_cache(CacheSz), + version = ?FILE_FORMAT_VERSION, + bump = ?BUMP, + base = ?BASE, + mod = ?MODULE + }, + + FreeListsPointer = 0, + NoColls = <<0:?COLL_CNTRS/unit:8>>, %% Buddy system counters. + FileHeader = file_header(Head0, FreeListsPointer, + ?NOT_PROPERLY_CLOSED, NoColls), + W0 = {0, [FileHeader | + <<0:(4*?SEGARRSZ)/unit:8>>]}, %% SegmentArray Pointers + + %% Remove cached pointers to segment array parts and segments: + lists:foreach(fun({I1,I2}) when is_integer(I1), is_integer(I2) -> ok; + ({K,V}) -> put(K, V) + end, erase()), + + %% Initialize array parts. + %% All parts before segments, for the sake of repair and initialization. + Zero = seg_zero(), + {Head1, Ws1} = init_parts(Head0, 0, no_parts(Next), Zero, []), + NoSegs = no_segs(Next), + + {Head, WsI, WsP} = init_segments(Head1, 0, NoSegs, Zero, [], []), + Ws2 = if + DoInitSegments -> WsP ++ WsI; + true -> WsP + end, + dets_utils:pwrite(Fd, Fname, [W0 | lists:append(Ws1) ++ Ws2]), + true = hash_invars(Head), + {ok, Head}. + +%% Returns a power of two not less than 256. +slots2(NoSlots) when NoSlots >= 256 -> + ?POW(dets_utils:log2(NoSlots)). + +init_parts(Head, PartNo, NoParts, Zero, Ws) when PartNo < NoParts -> + PartPos = ?SEGARRADDR(PartNo), + {NewHead, W, _Part} = alloc_part(Head, Zero, PartPos), + init_parts(NewHead, PartNo+1, NoParts, Zero, [W | Ws]); +init_parts(Head, _PartNo, _NoParts, _Zero, Ws) -> + {Head, Ws}. + +%% -> {Head, SegInitList, OtherList}; +%% SegPtrList = SegInitList = pwrite_list(). +init_segments(Head, SegNo, NoSegs, SegZero, WsP, WsI) when SegNo < NoSegs -> + {NewHead, WI, Ws} = allocate_segment(Head, SegZero, SegNo), + init_segments(NewHead, SegNo+1, NoSegs, SegZero, Ws ++ WsP, [WI | WsI]); +init_segments(Head, _SegNo, _NoSegs, _SegZero, WsP, WsI) -> + {Head, WsI, WsP}. + +%% -> {NewHead, SegInit, [SegPtr | PartStuff]} +allocate_segment(Head, SegZero, SegNo) -> + PartPos = ?SEGARRADDR(SegNo div ?SEGPARTSZ), + case get_arrpart(PartPos) of + undefined -> + %% may throw error: + {Head1, [InitArrPart, ArrPartPointer], Part} = + alloc_part(Head, SegZero, PartPos), + {NewHead, InitSegment, [SegPointer]} = + alloc_seg(Head1, SegZero, SegNo, Part), + {NewHead, InitSegment, [InitArrPart, SegPointer, ArrPartPointer]}; + Part -> + alloc_seg(Head, SegZero, SegNo, Part) + end. + +alloc_part(Head, PartZero, PartPos) -> + %% may throw error: + {NewHead, Part, _} = dets_utils:alloc(Head, adjsz(4 * ?SEGPARTSZ)), + arrpart_cache(PartPos, Part), + InitArrPart = {Part, PartZero}, % same size as segment + ArrPartPointer = {PartPos, <<Part:32>>}, + {NewHead, [InitArrPart, ArrPartPointer], Part}. + +alloc_seg(Head, SegZero, SegNo, Part) -> + %% may throw error: + {NewHead, Segment, _} = dets_utils:alloc(Head, adjsz(4 * ?SEGSZ)), + InitSegment = {Segment, SegZero}, + Pos = ?SEGPARTADDR(Part, SegNo), + segp_cache(Pos, Segment), + dets_utils:disk_map_segment(Segment, SegZero), + SegPointer = {Pos, <<Segment:32>>}, + {NewHead, InitSegment, [SegPointer]}. + +%% Read free lists (using a Buddy System) from file. +init_freelist(Head, true) -> + Pos = Head#head.freelists_p, + free_lists_from_file(Head, Pos). + +%% -> {ok, Fd, fileheader()} | throw(Error) +read_file_header(Fd, FileName) -> + {ok, Bin} = dets_utils:pread_close(Fd, FileName, 0, ?HEADSZ), + <<FreeList:32, Cookie:32, CP:32, Type2:32, + Version:32, M:32, Next:32, Kp:32, + NoObjects:32, NoKeys:32, MinNoSlots:32, MaxNoSlots:32, + HashMethod:32, N:32, NoCollsB:?COLL_CNTRS/binary, + MD5:?MD5SZ/binary>> = Bin, + <<_:12/binary,MD5DigestedPart:(?HEADSZ-?MD5SZ-12)/binary,_/binary>> = Bin, + {ok, EOF} = dets_utils:position_close(Fd, FileName, eof), + {ok, <<FileSize:32>>} = dets_utils:pread_close(Fd, FileName, EOF-4, 4), + {CL, <<>>} = lists:foldl(fun(LSz, {Acc,<<NN:32,R/binary>>}) -> + if + NN =:= 0 -> {Acc, R}; + true -> {[{LSz,NN} | Acc], R} + end + end, {[], NoCollsB}, lists:seq(4, ?MAXBUD-1)), + NoColls = + if + CL =:= [], NoObjects > 0 -> % Version 9(a) + undefined; + true -> + lists:reverse(CL) + end, + + FH = #fileheader{freelist = FreeList, + cookie = Cookie, + closed_properly = CP, + type = dets_utils:code_to_type(Type2), + version = Version, + m = M, + next = Next, + keypos = Kp, + no_objects = NoObjects, + no_keys = NoKeys, + min_no_slots = MinNoSlots, + max_no_slots = MaxNoSlots, + no_colls = NoColls, + hash_method = HashMethod, + read_md5 = MD5, + has_md5 = <<0:?MD5SZ/unit:8>> =/= MD5, + md5 = erlang:md5(MD5DigestedPart), + trailer = FileSize, + eof = EOF, + n = N, + mod = ?MODULE}, + {ok, Fd, FH}. + +%% -> {ok, head(), ExtraInfo} | {error, Reason} (Reason lacking file name) +%% ExtraInfo = true +check_file_header(FH, Fd) -> + HashBif = code_to_hash_method(FH#fileheader.hash_method), + 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 -> + {error, bad_version}; + FH#fileheader.has_md5, + FH#fileheader.read_md5 =/= FH#fileheader.md5 -> + {error, not_a_dets_file}; % harsh but fair + FH#fileheader.trailer =/= FH#fileheader.eof -> + {error, not_closed}; + HashBif =:= undefined -> + {error, bad_hash_bif}; + FH#fileheader.closed_properly =:= ?CLOSED_PROPERLY -> + {ok, true}; + FH#fileheader.closed_properly =:= ?NOT_PROPERLY_CLOSED -> + {error, not_closed}; + true -> + {error, not_a_dets_file} + end, + case Test of + {ok, ExtraInfo} -> + MaxObjSize = max_objsize(FH#fileheader.no_colls), + H = #head{ + m = FH#fileheader.m, + m2 = FH#fileheader.m * 2, + next = FH#fileheader.next, + fptr = Fd, + no_objects = FH#fileheader.no_objects, + no_keys = FH#fileheader.no_keys, + maxobjsize = MaxObjSize, + 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 = HashBif, + has_md5 = FH#fileheader.has_md5, + keypos = FH#fileheader.keypos, + min_no_slots = FH#fileheader.min_no_slots, + max_no_slots = FH#fileheader.max_no_slots, + no_collections = FH#fileheader.no_colls, + version = ?FILE_FORMAT_VERSION, + mod = ?MODULE, + bump = ?BUMP, + base = ?BASE}, + {ok, H, ExtraInfo}; + Error -> + Error + end. + +%% Inlined. +max_objsize(NoColls = undefined) -> + NoColls; +max_objsize(NoColls) -> + max_objsize(NoColls, 0). + +max_objsize([], Max) -> + Max; +max_objsize([{_,0} | L], Max) -> + max_objsize(L, Max); +max_objsize([{I,_} | L], _Max) -> + max_objsize(L, I). + +cache_segps(Fd, FileName, M) -> + NoParts = no_parts(M), + ArrStart = ?SEGARRADDR(0), + {ok, Bin} = dets_utils:pread_close(Fd, FileName, ArrStart, 4 * NoParts), + cache_arrparts(Bin, ?HEADEND, Fd, FileName). + +cache_arrparts(<<ArrPartPos:32, B/binary>>, Pos, Fd, FileName) -> + arrpart_cache(Pos, ArrPartPos), + {ok, ArrPartBin} = dets_utils:pread_close(Fd, FileName, + ArrPartPos, + ?SEGPARTSZ*4), + cache_segps1(Fd, ArrPartBin, ArrPartPos), + cache_arrparts(B, Pos+4, Fd, FileName); +cache_arrparts(<<>>, _Pos, _Fd, _FileName) -> + ok. + +cache_segps1(_Fd, <<0:32,_/binary>>, _P) -> + ok; +cache_segps1(Fd, <<S:32,B/binary>>, P) -> + dets_utils:disk_map_segment_p(Fd, S), + segp_cache(P, S), + cache_segps1(Fd, B, P+4); +cache_segps1(_Fd, <<>>, _P) -> + ok. + +no_parts(NoSlots) -> + ((NoSlots - 1) div (?SEGSZP * ?SEGPARTSZ)) + 1. + +no_segs(NoSlots) -> + ((NoSlots - 1) div ?SEGSZP) + 1. + +%%% +%%% Repair, conversion and initialization of a dets file. +%%% + +%%% bulk_input/3. Initialization, the general case (any stream of objects). +%%% output_objs/4. Initialization (general case) and repair. +%%% bchunk_init/2. Initialization using bchunk. + +bulk_input(Head, InitFun, _Cntrs) -> + bulk_input(Head, InitFun, make_ref(), 0). + +bulk_input(Head, InitFun, Ref, Seq) -> + fun(close) -> + _ = (catch InitFun(close)); + (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, Kp, Seq, []) of + {'EXIT', _Error} -> + _ = (catch NewInitFun(close)), + {error, invalid_objects_list}; + {L, NSeq} -> + {L, bulk_input(Head, NewInitFun, Ref, NSeq)} + end; + {Ref, Value} -> + {error, {init_fun, Value}}; + Error -> + throw({thrown, Error}) + end + end. + +bulk_objects([T | Ts], Head, Kp, Seq, L) -> + BT = term_to_binary(T), + Key = element(Kp, T), + bulk_objects(Ts, Head, Kp, Seq+1, [make_object(Head, Key, Seq, BT) | L]); +bulk_objects([], _Head, Kp, Seq, L) when is_integer(Kp), is_integer(Seq) -> + {L, Seq}. + +-define(FSCK_SEGMENT, 1). +-define(FSCK_SEGMENT2, 10000). + +-define(VEMPTY, {}). +-define(VSET(I, V, E), setelement(I, V, E)). +-define(VGET(I, V), element(I, V)). +-define(VEXT(S, V, T), + list_to_tuple(tuple_to_list(V) ++ lists:duplicate(S-tuple_size(V), T))). + +%% Number of bytes that will be handled before the cache is written to +%% file. Used when compacting or writing chunks. +-define(CACHE_SIZE, (60*?CHUNK_SIZE)). + +%% {LogSize,NoObjects} in Cntrs is replaced by +%% {LogSize,Position,{FileName,FileDescriptor},NoCollections}. +%% There is also an object {no, NoObjects, NoKeys}. +-define(COUNTERS, no). +-define(OBJ_COUNTER, 2). +-define(KEY_COUNTER, 3). + +output_objs(OldV, Head, SlotNums, Cntrs) when OldV =< 9 -> + fun(close) -> + %% Make sure that the segments are initialized in case + %% init_table has been called. + Cache = ?VEMPTY, + Acc = [], % This is the only way Acc can be empty. + true = ets:insert(Cntrs, {?FSCK_SEGMENT,0,[],0}), + true = ets:insert(Cntrs, {?COUNTERS, 0, 0}), + Fun = output_objs2(foo, Acc, OldV, Head, Cache, Cntrs, + SlotNums, bar), + Fun(close); + ([]) -> + output_objs(OldV, Head, SlotNums, Cntrs); + (L) -> + %% Information about number of objects per size is not + %% relevant for version 9. It is the number of collections + %% that matters. + true = ets:delete_all_objects(Cntrs), + true = ets:insert(Cntrs, {?COUNTERS, 0, 0}), + Es = bin2term(L, OldV, Head#head.keypos), + %% The cache is a tuple indexed by the (log) size. An element + %% is [BinaryObject]. + Cache = ?VEMPTY, + {NE, NAcc, NCache} = output_slots(Es, Head, Cache, Cntrs, 0, 0), + output_objs2(NE, NAcc, OldV, Head, NCache, Cntrs, SlotNums, 1) + end. + +output_objs2(E, Acc, OldV, Head, Cache, SizeT, SlotNums, 0) -> + NCache = write_all_sizes(Cache, SizeT, Head, more), + %% Number of handled file_sorter chunks before writing: + Max = erlang:max(1, erlang:min(tuple_size(NCache), 10)), + output_objs2(E, Acc, OldV, Head, NCache, SizeT, SlotNums, Max); +output_objs2(E, Acc, OldV, Head, Cache, SizeT, SlotNums, ChunkI) -> + fun(close) -> + {_, [], Cache1} = + if + Acc =:= [] -> {foo, [], Cache}; + true -> output_slot(Acc, Head, Cache, [], SizeT, 0, 0) + end, + _NCache = write_all_sizes(Cache1, SizeT, Head, no_more), + SegSz = ?ACTUAL_SEG_SIZE, + {_, SegEnd, _} = dets_utils:alloc(Head, adjsz(SegSz)), + [{?COUNTERS,NoObjects,NoKeys}] = ets:lookup(SizeT, ?COUNTERS), + Head1 = Head#head{no_objects = NoObjects, no_keys = NoKeys}, + true = ets:delete(SizeT, ?COUNTERS), + {NewHead, NL, _MaxSz, _End} = allocate_all_objects(Head1, SizeT), + %% It is not known until all objects have been collected + %% how many object collections there are per size. Now + %% that is known and the absolute positions of the object + %% collections can be calculated. + segment_file(SizeT, NewHead, NL, SegEnd), + {MinSlots, EstNoSlots, MaxSlots} = SlotNums, + if + EstNoSlots =:= bulk_init -> + {ok, 0, NewHead}; + true -> + EstNoSegs = no_segs(EstNoSlots), + MinNoSegs = no_segs(MinSlots), + MaxNoSegs = no_segs(MaxSlots), + NoSegs = no_segs(NoKeys), + Diff = abs(NoSegs - EstNoSegs), + if + Diff > 5, NoSegs =< MaxNoSegs, NoSegs >= MinNoSegs -> + {try_again, NoKeys}; + true -> + {ok, 0, NewHead} + end + end; + (L) -> + Es = bin2term(L, OldV, Head#head.keypos), + {NE, NAcc, NCache} = + output_slots(E, Es, Acc, Head, Cache, SizeT, 0, 0), + output_objs2(NE, NAcc, OldV, Head, NCache, SizeT, SlotNums, + ChunkI-1) + end. + +%%% Compaction. + +compact_init(ReadHead, WriteHead, TableParameters) -> + SizeT = ets:new(dets_compact, []), + #head{no_keys = NoKeys, no_objects = NoObjects} = ReadHead, + + NoObjsPerSize = TableParameters#?HASH_PARMS.no_colls, + {NewWriteHead, Bases, SegAddr, SegEnd} = + prepare_file_init(NoObjects, NoKeys, NoObjsPerSize, SizeT, WriteHead), + + Input = compact_input(ReadHead, NewWriteHead, SizeT, tuple_size(Bases)), + Output = fast_output(NewWriteHead, SizeT, Bases, SegAddr, SegEnd), + TmpDir = filename:dirname(NewWriteHead#head.filename), + Reply = (catch file_sorter:sort(Input, Output, + [{format, binary},{tmpdir, TmpDir}, + {header, 1}])), % compact_objs/9: 13 bytes + ets:delete(SizeT), + Reply. + +compact_input(Head, WHead, SizeT, NoSizes) -> + L = dets_utils:all_allocated_as_list(Head), + Cache = ?VEXT(NoSizes, ?VEMPTY, [0 | []]), + compact_input(Head, WHead, SizeT, Cache, L). + +compact_input(Head, WHead, SizeT, Cache, L) -> + fun(close) -> + ok; + (read) -> + compact_read(Head, WHead, SizeT, Cache, L, 0, [], 0) + end. + +compact_read(_Head, WHead, SizeT, Cache, [], _Min, [], _ASz) -> + _ = fast_write_all_sizes(Cache, SizeT, WHead), + end_of_input; +compact_read(Head, WHead, SizeT, Cache, L, Min, SegBs, ASz) + when ASz + Min >= ?CACHE_SIZE, ASz > 0 -> + NCache = fast_write_all_sizes(Cache, SizeT, WHead), + {SegBs, compact_input(Head, WHead, SizeT, NCache, L)}; +compact_read(Head, WHead, SizeT, Cache, [[From | To] | L], Min, SegBs, ASz) -> + Max = erlang:max(?CHUNK_SIZE*3, Min), + case check_pread_arg(Max, Head) of + true -> + case dets_utils:pread_n(Head#head.fptr, From, Max) of + eof -> + %% Should never happen since compaction will not + %% be tried unless the file trailer is valid. + not_ok; % try a proper repair + Bin1 when byte_size(Bin1) < Min -> + %% The last object may not be padded. + Pad = Min - byte_size(Bin1), + NewBin = <<Bin1/binary, 0:Pad/unit:8>>, + compact_objs(Head, WHead, SizeT, NewBin, L, + From, To, SegBs, Cache, ASz); + NewBin -> + compact_objs(Head, WHead, SizeT, NewBin, L, + From, To, SegBs, Cache, ASz) + end; + false -> + not_ok % try a proper repair + end. + +compact_objs(Head, WHead, SizeT, Bin, L, From, To, SegBs, Cache, ASz) + when From =:= To -> + case L of + [] -> + {SegBs, compact_input(Head, WHead, SizeT, Cache, L)}; + [[From1 | To1] | L1] -> + Skip1 = From1 - From, + case Bin of + <<_:Skip1/binary,NewBin/binary>> -> + compact_objs(Head, WHead, SizeT, NewBin, L1, From1, To1, + SegBs, Cache, ASz); + _ when byte_size(Bin) < Skip1 -> + compact_read(Head, WHead, SizeT, Cache, L, 0, SegBs, ASz) + end + end; +compact_objs(Head, WHead, SizeT, <<Size:32, St:32, _Sz:32, KO/binary>> = Bin, + L, From, To, SegBs, Cache, ASz) when St =:= ?ACTIVE -> + LSize = sz2pos(Size), + Size2 = ?POW(LSize-1), + if + byte_size(Bin) >= Size2 -> + NASz = ASz + Size2, + <<SlotObjs:Size2/binary, NewBin/binary>> = Bin, + Term = if + Head#head.type =:= set -> + binary_to_term(KO); + true -> + <<_KSz:32,B2/binary>> = KO, + binary_to_term(B2) + end, + Key = element(Head#head.keypos, Term), + Slot = db_hash(Key, Head), + From1 = From + Size2, + [Addr | AL] = ?VGET(LSize, Cache), + NCache = ?VSET(LSize, Cache, [Addr + Size2 | [SlotObjs | AL]]), + NSegBs = [<<Slot:32,Size:32,Addr:32,LSize:8>> | SegBs], + compact_objs(Head, WHead, SizeT, NewBin, L, From1, + To, NSegBs, NCache, NASz); + true -> + compact_read(Head, WHead, SizeT, Cache, [[From|To] | L], + Size2, SegBs, ASz) + end; +compact_objs(Head, WHead, SizeT, <<_:32, _St:32, _:32, _/binary>> = Bin, + L, From, To, SegBs, Cache, ASz) + when byte_size(Bin) >= ?ACTUAL_SEG_SIZE -> % , _St =/= ?ACTIVE + <<_:?ACTUAL_SEG_SIZE/binary, NewBin/binary>> = Bin, + compact_objs(Head, WHead, SizeT, NewBin, L, From + ?ACTUAL_SEG_SIZE, + To, SegBs, Cache, ASz); +compact_objs(Head, WHead, SizeT, <<_:32, _St:32, _:32, _/binary>> = Bin, + L, From, To, SegBs, Cache, ASz) + when byte_size(Bin) < ?ACTUAL_SEG_SIZE -> % , _St =/= ?ACTIVE + compact_read(Head, WHead, SizeT, Cache, [[From|To] | L], + ?ACTUAL_SEG_SIZE, SegBs, ASz); +compact_objs(Head, WHead, SizeT, _Bin, L, From, To, SegBs, Cache, ASz) -> + compact_read(Head, WHead, SizeT, Cache, [[From|To] | L], 0, SegBs, ASz). + +%%% End compaction. + +%%% Bchunk. + +read_bchunks(Head, L) -> + read_bchunks(Head, L, 0, [], 0). + +read_bchunks(_Head, L, Min, Bs, ASz) when ASz + Min >= 4*?CHUNK_SIZE, + Bs =/= [] -> + {lists:reverse(Bs), L}; +read_bchunks(Head, {From, To, L}, Min, Bs, ASz) -> + Max = erlang:max(?CHUNK_SIZE*2, Min), + case check_pread_arg(Max, Head) of + true -> + case dets_utils:pread_n(Head#head.fptr, From, Max) of + eof -> + %% Should never happen. + {error, premature_eof}; + NewBin when byte_size(NewBin) >= Min -> + bchunks(Head, L, NewBin, Bs, ASz, From, To); + Bin1 when To - From =:= Min, L =:= <<>> -> + %% when byte_size(Bin1) < Min. + %% The last object may not be padded. + Pad = Min - byte_size(Bin1), + NewBin = <<Bin1/binary, 0:Pad/unit:8>>, + bchunks(Head, L, NewBin, Bs, ASz, From, To); + _ -> + {error, premature_eof} + end; + false -> + {error, dets_utils:bad_object(bad_object, {read_bchunks, Max})} + end. + +bchunks(Head, L, Bin, Bs, ASz, From, To) when From =:= To -> + if + L =:= <<>> -> + {finished, lists:reverse(Bs)}; + true -> + <<From1:32, To1:32, L1/binary>> = L, + Skip1 = From1 - From, + case Bin of + <<_:Skip1/binary,NewBin/binary>> -> + bchunks(Head, L1, NewBin, Bs, ASz, From1, To1); + _ when byte_size(Bin) < Skip1 -> + read_bchunks(Head, {From1,To1,L1}, 0, Bs, ASz) + end + end; +bchunks(Head, L, <<Size:32, St:32, _Sz:32, KO/binary>> = Bin, Bs, ASz, + From, To) when St =:= ?ACTIVE; St =:= ?FREE -> + LSize = sz2pos(Size), + Size2 = ?POW(LSize-1), + if + byte_size(Bin) >= Size2 -> + <<B0:Size2/binary, NewBin/binary>> = Bin, + %% LSize and Slot are used in make_slots/6. The reason to + %% calculate Slot here is to reduce the CPU load in + %% make_slots/6. + Term = if + Head#head.type =:= set -> + binary_to_term(KO); + true -> + <<_KSz:32,B2/binary>> = KO, + binary_to_term(B2) + end, + Key = element(Head#head.keypos, Term), + Slot = db_hash(Key, Head), + B = {LSize,Slot,B0}, + bchunks(Head, L, NewBin, [B | Bs], ASz + Size2, From+Size2, To); + true -> + read_bchunks(Head, {From, To, L}, Size2, Bs, ASz) + end; +bchunks(Head, L, <<_:32, _St:32, _:32, _/binary>> = Bin, Bs, ASz, From, To) + when byte_size(Bin) >= ?ACTUAL_SEG_SIZE -> + <<_:?ACTUAL_SEG_SIZE/binary, NewBin/binary>> = Bin, + bchunks(Head, L, NewBin, Bs, ASz, From + ?ACTUAL_SEG_SIZE, To); +bchunks(Head, L, <<_:32, _St:32, _:32, _/binary>> = Bin, Bs, ASz, From, To) + when byte_size(Bin) < ?ACTUAL_SEG_SIZE -> + read_bchunks(Head, {From, To, L}, ?ACTUAL_SEG_SIZE, Bs, ASz); +bchunks(Head, L, _Bin, Bs, ASz, From, To) -> + read_bchunks(Head, {From, To, L}, 0, Bs, ASz). + +%%% End bchunk. + +%% -> {ok, NewHead} | throw(Error) | Error +bchunk_init(Head, InitFun) -> + Ref = make_ref(), + %% The non-empty list of data begins with the table parameters. + case catch {Ref, InitFun(read)} of + {Ref, end_of_input} -> + {error, {init_fun, end_of_input}}; + {Ref, {[], NInitFun}} when is_function(NInitFun) -> + bchunk_init(Head, NInitFun); + {Ref, {[ParmsBin | L], NInitFun}} + when is_list(L), is_function(NInitFun) -> + #head{fptr = Fd, type = Type, keypos = Kp, + auto_save = Auto, cache = Cache, + filename = Fname, ram_file = Ram, + name = Tab} = Head, + case try_bchunk_header(ParmsBin, Head) of + {ok, Parms} -> + #?HASH_PARMS{no_objects = NoObjects, + no_keys = NoKeys, + no_colls = NoObjsPerSize} = Parms, + CacheSz = dets_utils:cache_size(Cache), + {ok, Head1} = + prep_table_copy(Fd, Tab, Fname, Type, + Kp, Ram, CacheSz, + Auto, Parms), + SizeT = ets:new(dets_init, []), + {NewHead, Bases, SegAddr, SegEnd} = + prepare_file_init(NoObjects, NoKeys, + NoObjsPerSize, SizeT, Head1), + ECache = ?VEXT(tuple_size(Bases), ?VEMPTY, [0 | []]), + Input = + fun(close) -> + _ = (catch NInitFun(close)); + (read) -> + do_make_slots(L, ECache, SizeT, NewHead, Ref, + 0, NInitFun) + end, + Output = fast_output(NewHead, SizeT, Bases, SegAddr,SegEnd), + TmpDir = filename:dirname(Head#head.filename), + Reply = (catch file_sorter:sort(Input, Output, + [{format, binary}, + {tmpdir, TmpDir}, + {header, 1}])), + ets:delete(SizeT), + Reply; + not_ok -> + {error, {init_fun, ParmsBin}} + end; + {Ref, Value} -> + {error, {init_fun, Value}}; + Error -> + {thrown, Error} + end. + +try_bchunk_header(ParmsBin, Head) -> + #head{type = Type, keypos = Kp, hash_bif = HashBif} = Head, + HashMethod = hash_method_to_code(HashBif), + case catch binary_to_term(ParmsBin) of + Parms when is_record(Parms, ?HASH_PARMS), + Parms#?HASH_PARMS.type =:= Type, + Parms#?HASH_PARMS.keypos =:= Kp, + Parms#?HASH_PARMS.hash_method =:= HashMethod, + Parms#?HASH_PARMS.bchunk_format_version =:= + ?BCHUNK_FORMAT_VERSION -> + {ok, Parms}; + _ -> + not_ok + end. + +bchunk_input(InitFun, SizeT, Head, Ref, Cache, ASz) -> + fun(close) -> + _ = (catch InitFun(close)); + (read) -> + case catch {Ref, InitFun(read)} of + {Ref, end_of_input} -> + _ = fast_write_all_sizes(Cache, SizeT, Head), + end_of_input; + {Ref, {L, NInitFun}} when is_list(L), is_function(NInitFun) -> + do_make_slots(L, Cache, SizeT, Head, Ref, ASz, + NInitFun); + {Ref, Value} -> + {error, {init_fun, Value}}; + Error -> + throw({thrown, Error}) + end + end. + +do_make_slots(L, Cache, SizeT, Head, Ref, ASz, InitFun) -> + case catch make_slots(L, Cache, [], ASz) of + {'EXIT', _} -> + _ = (catch InitFun(close)), + {error, invalid_objects_list}; + {Cache1, SegBs, NASz} when NASz > ?CACHE_SIZE -> + NCache = fast_write_all_sizes(Cache1, SizeT, Head), + F = bchunk_input(InitFun, SizeT, Head, Ref, NCache, 0), + {SegBs, F}; + {NCache, SegBs, NASz} -> + F = bchunk_input(InitFun, SizeT, Head, Ref, NCache, NASz), + {SegBs, F} + end. + +make_slots([{LSize,Slot,<<Size:32, St:32, Sz:32, KO/binary>> = Bin0} | Bins], + Cache, SegBs, ASz) -> + Bin = if + St =:= ?ACTIVE -> + Bin0; + St =:= ?FREE -> + <<Size:32,?ACTIVE:32,Sz:32,KO/binary>> + end, + BSz = byte_size(Bin0), + true = (BSz =:= ?POW(LSize-1)), + NASz = ASz + BSz, + [Addr | L] = ?VGET(LSize, Cache), + NSegBs = [<<Slot:32,Size:32,Addr:32,LSize:8>> | SegBs], + NCache = ?VSET(LSize, Cache, [Addr + BSz | [Bin | L]]), + make_slots(Bins, NCache, NSegBs, NASz); +make_slots([], Cache, SegBs, ASz) -> + {Cache, SegBs, ASz}. + +fast_output(Head, SizeT, Bases, SegAddr, SegEnd) -> + fun(close) -> + fast_output_end(Head, SizeT); + (L) -> + case file:position(Head#head.fptr, SegAddr) of + {ok, SegAddr} -> + NewSegAddr = write_segment_file(L, Bases, Head, [], + SegAddr, SegAddr), + fast_output2(Head, SizeT, Bases, NewSegAddr, + SegAddr, SegEnd); + Error -> + catch dets_utils:file_error(Error, Head#head.filename) + end + end. + +fast_output2(Head, SizeT, Bases, SegAddr, SS, SegEnd) -> + fun(close) -> + FinalZ = SegEnd - SegAddr, + dets_utils:write(Head, dets_utils:make_zeros(FinalZ)), + fast_output_end(Head, SizeT); + (L) -> + NewSegAddr = write_segment_file(L, Bases, Head, [], SegAddr, SS), + fast_output2(Head, SizeT, Bases, NewSegAddr, SS, SegEnd) + end. + +fast_output_end(Head, SizeT) -> + case ets:foldl(fun({_Sz,_Pos,Cnt,NoC}, Acc) -> (Cnt =:= NoC) and Acc end, + true, SizeT) of + true -> {ok, Head}; + false -> {error, invalid_objects_list} + end. + +%% Inlined. +write_segment_file([<<Slot:32,BSize:32,AddrToBe:32,LSize:8>> | Bins], + Bases, Head, Ws, SegAddr, SS) -> + %% Should call slot_position/1, but since all segments are + %% allocated in a sequence, the position of a slot can be + %% calculated faster. + Pos = SS + ?SZOBJP*4 * Slot, % Same as Pos = slot_position(Slot). + write_segment_file(Bins, Bases, Head, Ws, SegAddr, SS, Pos, + BSize, AddrToBe, LSize); +write_segment_file([], _Bases, Head, Ws, SegAddr, _SS) -> + dets_utils:write(Head, Ws), + SegAddr. + +write_segment_file(Bins, Bases, Head, Ws, SegAddr, SS, Pos, BSize, + AddrToBe, LSize) when Pos =:= SegAddr -> + Addr = AddrToBe + element(LSize, Bases), + NWs = [Ws | <<BSize:32,Addr:32>>], + write_segment_file(Bins, Bases, Head, NWs, SegAddr + ?SZOBJP*4, SS); +write_segment_file(Bins, Bases, Head, Ws, SegAddr, SS, Pos, BSize, + AddrToBe, LSize) when Pos - SegAddr < 100 -> + Addr = AddrToBe + element(LSize, Bases), + NoZeros = Pos - SegAddr, + NWs = [Ws | <<0:NoZeros/unit:8,BSize:32,Addr:32>>], + NSegAddr = SegAddr + NoZeros + ?SZOBJP*4, + write_segment_file(Bins, Bases, Head, NWs, NSegAddr, SS); +write_segment_file(Bins, Bases, Head, Ws, SegAddr, SS, Pos, BSize, + AddrToBe, LSize) -> + Addr = AddrToBe + element(LSize, Bases), + NoZeros = Pos - SegAddr, + NWs = [Ws, dets_utils:make_zeros(NoZeros) | <<BSize:32,Addr:32>>], + NSegAddr = SegAddr + NoZeros + ?SZOBJP*4, + write_segment_file(Bins, Bases, Head, NWs, NSegAddr, SS). + +fast_write_all_sizes(Cache, SizeT, Head) -> + CacheL = lists:reverse(tuple_to_list(Cache)), + fast_write_sizes(CacheL, tuple_size(Cache), SizeT, Head, [], []). + +fast_write_sizes([], _Sz, _SizeT, Head, NCL, PwriteList) -> + #head{filename = FileName, fptr = Fd} = Head, + ok = dets_utils:pwrite(Fd, FileName, PwriteList), + list_to_tuple(NCL); +fast_write_sizes([[_Addr] = C | CL], Sz, SizeT, Head, NCL, PwriteList) -> + fast_write_sizes(CL, Sz-1, SizeT, Head, [C | NCL], PwriteList); +fast_write_sizes([[Addr | C] | CL], Sz, SizeT, Head, NCL, PwriteList) -> + case ets:lookup(SizeT, Sz) of + [] -> + throw({error, invalid_objects_list}); + [{Sz,Position,_ObjCounter,_NoCollections}] -> + %% Update ObjCounter: + NoColls = length(C), + _ = ets:update_counter(SizeT, Sz, {3, NoColls}), + Pos = Position + Addr - NoColls*?POW(Sz-1), + fast_write_sizes(CL, Sz-1, SizeT, Head, [[Addr] | NCL], + [{Pos,lists:reverse(C)} | PwriteList]) + end. + +prepare_file_init(NoObjects, NoKeys, NoObjsPerSize, SizeT, Head) -> + SegSz = ?ACTUAL_SEG_SIZE, + {_, SegEnd, _} = dets_utils:alloc(Head, adjsz(SegSz)), + Head1 = Head#head{no_objects = NoObjects, no_keys = NoKeys}, + true = ets:insert(SizeT, {?FSCK_SEGMENT,0,[],0}), + lists:foreach(fun({LogSz,NoColls}) -> + true = ets:insert(SizeT, {LogSz+1,0,0,NoColls}) + end, NoObjsPerSize), + {NewHead, NL0, MaxSz, EndOfFile} = allocate_all_objects(Head1, SizeT), + [{?FSCK_SEGMENT,SegAddr,[],0} | NL] = NL0, + true = ets:delete_all_objects(SizeT), + lists:foreach(fun(X) -> true = ets:insert(SizeT, X) end, NL), + Bases = lists:foldl(fun({LSz,P,_D,_N}, A) -> setelement(LSz,A,P) end, + erlang:make_tuple(MaxSz, 0), NL), + Est = lists:foldl(fun({LSz,_,_,N}, A) -> A + ?POW(LSz-1)*N end, 0, NL), + ok = write_bytes(NewHead, EndOfFile, Est), + {NewHead, Bases, SegAddr, SegEnd}. + +%% Writes "zeros" to the file. This ensures that the file blocks are +%% allocated more or less contiguously, which reduces the seek times +%% to a minimum when the file is later read serially from beginning to +%% end (as is done when calling select and the like). A well-formed +%% file will be created also if nothing is written (as is the case for +%% small files, for efficiency). +write_bytes(_Head, _EndOfFile, Est) when Est < ?CACHE_SIZE -> + ok; +write_bytes(Head, EndOfFile, _Est) -> + Fd = Head#head.fptr, + {ok, Start} = file:position(Fd, eof), + BytesToWrite = EndOfFile - Start, + SizeInKB = 64, + Bin = list_to_binary(lists:duplicate(SizeInKB * 4, lists:seq(0, 255))), + write_loop(Head, BytesToWrite, Bin). + +write_loop(Head, BytesToWrite, Bin) when BytesToWrite >= byte_size(Bin) -> + case file:write(Head#head.fptr, Bin) of + ok -> write_loop(Head, BytesToWrite - byte_size(Bin), Bin); + Error -> dets_utils:file_error(Error, Head#head.filename) + end; +write_loop(_Head, 0, _Bin) -> + ok; +write_loop(Head, BytesToWrite, Bin) -> + <<SmallBin:BytesToWrite/binary,_/binary>> = Bin, + write_loop(Head, BytesToWrite, SmallBin). + +%% 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, SizeT) -> + DTL = lists:reverse(lists:keysort(1, ets:tab2list(SizeT))), + MaxSz = element(1, hd(DTL)), + SegSize = ?ACTUAL_SEG_SIZE, + {Head1, HSz, HN, HA} = alloc_hole(MaxSz, Head, SegSize), + {Head2, NL} = allocate_all(Head1, DTL, []), + %% Find the position that will be the end of the file by allocating + %% a minimal object. + {_Head, EndOfFile, _} = dets_utils:alloc(Head2, ?BUMP), + Head3 = free_hole(Head2, HSz, HN, HA), + NewHead = Head3#head{maxobjsize = max_objsize(Head3#head.no_collections)}, + {NewHead, NL, MaxSz, EndOfFile}. + +alloc_hole(LSize, Head, SegSz) when ?POW(LSize-1) > SegSz -> + Size = ?POW(LSize-1), + {_, SegAddr, _} = dets_utils:alloc(Head, adjsz(SegSz)), + {_, Addr, _} = dets_utils:alloc(Head, adjsz(Size)), + N = (Addr - SegAddr) div SegSz, + Head1 = dets_utils:alloc_many(Head, SegSz, N, SegAddr), + {Head1, SegSz, N, SegAddr}; +alloc_hole(_MaxSz, 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, adjsz(Size)), + free_hole(Head1, Size, N-1, Addr+Size). + +%% One (temporary) file for each buddy size, write all objects of that +%% size to the file. +allocate_all(Head, [{?FSCK_SEGMENT,_,Data,_}], L) -> + %% And one file for the segments... + %% Note that space for the array parts and the segments has + %% already been allocated, but the segments have not been + %% initialized on disk. + NoParts = no_parts(Head#head.next), + %% All parts first, ensured by init_segments/6. + Addr = ?BASE + NoParts * 4 * ?SEGPARTSZ, + {Head, [{?FSCK_SEGMENT,Addr,Data,0} | L]}; +allocate_all(Head, [{LSize,_,Data,NoCollections} | DTL], L) -> + Size = ?POW(LSize-1), + {_Head, Addr, _} = dets_utils:alloc(Head, adjsz(Size)), + Head1 = dets_utils:alloc_many(Head, Size, NoCollections, Addr), + NoColls = Head1#head.no_collections, + NewNoColls = orddict:update_counter(LSize-1, NoCollections, NoColls), + NewHead = Head1#head{no_collections = NewNoColls}, + E = {LSize,Addr,Data,NoCollections}, + allocate_all(NewHead, DTL, [E | L]). + +bin2term(Bin, 9, Kp) -> + bin2term1(Bin, Kp, []); +bin2term(Bin, 8, Kp) -> + bin2term_v8(Bin, Kp, []). + +bin2term1([<<Slot:32, Seq:32, BinTerm/binary>> | BTs], Kp, L) -> + Term = binary_to_term(BinTerm), + Key = element(Kp, Term), + bin2term1(BTs, Kp, [{Slot, Key, Seq, Term, BinTerm} | L]); +bin2term1([], _Kp, L) -> + lists:reverse(L). + +bin2term_v8([<<Slot:32, BinTerm/binary>> | BTs], Kp, L) -> + Term = binary_to_term(BinTerm), + Key = element(Kp, Term), + bin2term_v8(BTs, Kp, [{Slot, Key, foo, Term, BinTerm} | L]); +bin2term_v8([], _Kp, L) -> + lists:reverse(L). + +write_all_sizes({}=Cache, _SizeT, _Head, _More) -> + Cache; +write_all_sizes(Cache, SizeT, Head, More) -> + CacheL = lists:reverse(tuple_to_list(Cache)), + Sz = length(CacheL), + NCL = case ets:info(SizeT, size) of + 1 when More =:= no_more -> % COUNTERS only... + all_sizes(CacheL, Sz, SizeT); + _ -> + write_sizes(CacheL, Sz, SizeT, Head) + end, + list_to_tuple(NCL). + +all_sizes([]=CL, _Sz, _SizeT) -> + CL; +all_sizes([[]=C | CL], Sz, SizeT) -> + [C | all_sizes(CL, Sz-1, SizeT)]; +all_sizes([C0 | CL], Sz, SizeT) -> + C = lists:reverse(C0), + NoCollections = length(C), + true = ets:insert(SizeT, {Sz,0,C,NoCollections}), + [[] | all_sizes(CL, Sz-1, SizeT)]. + +write_sizes([]=CL, _Sz, _SizeT, _Head) -> + CL; +write_sizes([[]=C | CL], Sz, SizeT, Head) -> + [C | write_sizes(CL, Sz-1, SizeT, Head)]; +write_sizes([C | CL], Sz, SizeT, Head) -> + {FileName, Fd} = + case ets:lookup(SizeT, Sz) of + [] -> + temp_file(Head, SizeT, Sz); + [{_,_,{FN,F},_}] -> + {FN, F} + end, + NoCollections = length(C), + _ = ets:update_counter(SizeT, Sz, {4,NoCollections}), + case file:write(Fd, lists:reverse(C)) of + ok -> + [[] | write_sizes(CL, Sz-1, SizeT, Head)]; + Error -> + dets_utils:file_error(FileName, Error) + end. + +output_slots([E | Es], Head, Cache, SizeT, NoKeys, NoObjs) -> + output_slots(E, Es, [E], Head, Cache, SizeT, NoKeys, NoObjs); +output_slots([], _Head, Cache, SizeT, NoKeys, NoObjs) -> + _ = ets:update_counter(SizeT, ?COUNTERS, {?OBJ_COUNTER,NoObjs}), + _ = ets:update_counter(SizeT, ?COUNTERS, {?KEY_COUNTER,NoKeys}), + {not_a_tuple, [], Cache}. + +output_slots(E, [E1 | Es], Acc, Head, Cache, SizeT, NoKeys, NoObjs) + when element(1, E) =:= element(1, E1) -> + output_slots(E1, Es, [E1 | Acc], Head, Cache, SizeT, NoKeys, NoObjs); +output_slots(E, [], Acc, _Head, Cache, SizeT, NoKeys, NoObjs) -> + _ = ets:update_counter(SizeT, ?COUNTERS, {?OBJ_COUNTER,NoObjs}), + _ = ets:update_counter(SizeT, ?COUNTERS, {?KEY_COUNTER,NoKeys}), + {E, Acc, Cache}; +output_slots(_E, L, Acc, Head, Cache, SizeT, NoKeys, NoObjs) -> + output_slot(Acc, Head, Cache, L, SizeT, NoKeys, NoObjs). + +output_slot(Es, Head, Cache, L, SizeT, NoKeys, NoObjs) -> + Slot = element(1, hd(Es)), + %% Plain lists:sort/1 will do. + {Bins, Size, No, KNo} = prep_slot(lists:sort(Es), Head), + NNoKeys = NoKeys + KNo, + NNoObjs = NoObjs + No, + + %% First the object collection. + BSize = Size + ?OHDSZ, + LSize = sz2pos(BSize), + Size2 = ?POW(LSize-1), + Pad = <<0:(Size2-BSize)/unit:8>>, + BinObject = [<<BSize:32, ?ACTIVE:32>>, Bins | Pad], + Cache1 = + if + LSize > tuple_size(Cache) -> + C1 = ?VEXT(LSize, Cache, []), + ?VSET(LSize, C1, [BinObject]); + true -> + CL = ?VGET(LSize, Cache), + ?VSET(LSize, Cache, [BinObject | CL]) + end, + + %% Then the pointer to the object collection. + %% Cannot yet determine the absolute pointers; segment_file/4 does that. + PBin = <<Slot:32,BSize:32,LSize:8>>, + PL = ?VGET(?FSCK_SEGMENT, Cache1), + NCache = ?VSET(?FSCK_SEGMENT, Cache1, [PBin | PL]), + output_slots(L, Head, NCache, SizeT, NNoKeys, NNoObjs). + +prep_slot(L, Head) when Head#head.type =/= set -> + prep_slot(L, Head, []); +prep_slot([{_Slot,Key,_Seq,_T,BT} | L], _Head) -> + prep_set_slot(L, Key, BT, 0, 0, 0, []). + +prep_slot([{_Slot, Key, Seq, T, _BT} | L], Head, W) -> + prep_slot(L, Head, [{Key, {Seq, {insert,T}}} | W]); +prep_slot([], Head, W) -> + WLs = dets_utils:family(W), + {[], Bins, Size, No, KNo, _} = + eval_slot(WLs, [], Head#head.type, [], [], 0, 0, 0, false), + {Bins, Size, No, KNo}. + +%% Optimization, prep_slot/3 would work for set tables as well. +prep_set_slot([{_,K,_Seq,_T1,BT1} | L], K, _BT, Sz, NoKeys, NoObjs, Ws) -> + prep_set_slot(L, K, BT1, Sz, NoKeys, NoObjs, Ws); +prep_set_slot([{_,K1,_Seq,_T1,BT1} | L], _K, BT, Sz, NoKeys, NoObjs, Ws) -> + BSize = byte_size(BT) + 4, + NWs = [Ws,<<BSize:32>>|BT], + prep_set_slot(L, K1, BT1, Sz+BSize, NoKeys+1, NoObjs+1, NWs); +prep_set_slot([], _K, BT, Sz, NoKeys, NoObjs, Ws) -> + BSize = byte_size(BT) + 4, + {[Ws, <<BSize:32>> | BT], Sz + BSize, NoKeys+1, NoObjs+1}. + +segment_file(SizeT, Head, FileData, SegEnd) -> + I = 2, + true = ets:delete_all_objects(SizeT), + lists:foreach(fun(X) -> true = ets:insert(SizeT, X) end, FileData), + [{?FSCK_SEGMENT,SegAddr,Data,0} | FileData1] = FileData, + NewData = + case Data of + {InFile,In0} -> + {OutFile, Out} = temp_file(Head, SizeT, I), + file:close(In0), + {ok, In} = dets_utils:open(InFile, [raw,binary,read]), + {ok, 0} = dets_utils:position(In, InFile, bof), + seg_file(SegAddr, SegAddr, In, InFile, Out, OutFile, SizeT, + SegEnd), + file:close(In), + file:delete(InFile), + {OutFile,Out}; + Objects -> + {LastAddr, B} = seg_file(Objects, SegAddr, SegAddr, SizeT, []), + dets_utils:disk_map_segment(SegAddr, B), + FinalZ = SegEnd - LastAddr, + [B | dets_utils:make_zeros(FinalZ)] + end, + %% Restore the positions. + true = ets:delete_all_objects(SizeT), + %% To get the segments copied first by dets:fsck_copy/4, use a big + %% number here, FSCK_SEGMENT2. + lists:foreach(fun(X) -> true = ets:insert(SizeT, X) end, + [{?FSCK_SEGMENT2,SegAddr,NewData,0} | FileData1]), + ok. + +seg_file(Addr, SS, In, InFile, Out, OutFile, SizeT, SegEnd) -> + case dets_utils:read_n(In, 4500) of + eof -> + FinalZ = SegEnd - Addr, + dets_utils:fwrite(Out, OutFile, dets_utils:make_zeros(FinalZ)); + Bin -> + {NewAddr, L} = seg_file(Bin, Addr, SS, SizeT, []), + dets_utils:disk_map_segment(Addr, L), + ok = dets_utils:fwrite(Out, OutFile, L), + seg_file(NewAddr, SS, In, InFile, Out, OutFile, SizeT, SegEnd) + end. + +seg_file(<<Slot:32,BSize:32,LSize:8,T/binary>>, Addr, SS, SizeT, L) -> + seg_file_item(T, Addr, SS, SizeT, L, Slot, BSize, LSize); +seg_file([<<Slot:32,BSize:32,LSize:8>> | T], Addr, SS, SizeT, L) -> + seg_file_item(T, Addr, SS, SizeT, L, Slot, BSize, LSize); +seg_file([], Addr, _SS, _SizeT, L) -> + {Addr, lists:reverse(L)}; +seg_file(<<>>, Addr, _SS, _SizeT, L) -> + {Addr, lists:reverse(L)}. + +seg_file_item(T, Addr, SS, SizeT, L, Slot, BSize, LSize) -> + %% Should call slot_position/1, but since all segments are + %% allocated in a sequence, the position of a slot can be + %% calculated faster. + SlotPos = SS + ?SZOBJP*4 * Slot, % SlotPos = slot_position(Slot) + NoZeros = SlotPos - Addr, + PSize = NoZeros+?SZOBJP*4, + Inc = ?POW(LSize-1), + CollP = ets:update_counter(SizeT, LSize, Inc) - Inc, + PointerBin = if + NoZeros =:= 0 -> + <<BSize:32, CollP:32>>; + NoZeros > 100 -> + [dets_utils:make_zeros(NoZeros) | + <<BSize:32, CollP:32>>]; + true -> + <<0:NoZeros/unit:8, BSize:32, CollP:32>> + end, + seg_file(T, Addr + PSize, SS, SizeT, [PointerBin | L]). + +temp_file(Head, SizeT, N) -> + TmpName = lists:concat([Head#head.filename, '.', N]), + {ok, Fd} = dets_utils:open(TmpName, [raw, binary, write]), + %% The file table is consulted when cleaning up. + true = ets:insert(SizeT, {N,0,{TmpName,Fd},0}), + {TmpName, Fd}. + +%% Does not close Fd. +fsck_input(Head, Fd, Cntrs, FileHeader) -> + MaxSz0 = case FileHeader#fileheader.has_md5 of + true when is_integer(FileHeader#fileheader.no_colls) -> + ?POW(max_objsize(FileHeader#fileheader.no_colls)); + _ -> + %% The file is not compressed, so the bucket size + %% cannot exceed the filesize, for all buckets. + case file:position(Fd, eof) of + {ok, Pos} -> + Pos; + _ -> + 1 bsl 32 + end + end, + MaxSz = erlang:max(MaxSz0, ?CHUNK_SIZE), + State0 = fsck_read(?BASE, Fd, [], 0), + fsck_input(Head, State0, Fd, MaxSz, Cntrs). + +fsck_input(Head, State, Fd, MaxSz, Cntrs) -> + fun(close) -> + ok; + (read) -> + case State of + done -> + end_of_input; + {done, L, _Seq} -> + R = count_input(Head, Cntrs, L), + {R, fsck_input(Head, done, Fd, MaxSz, Cntrs)}; + {cont, L, Bin, Pos, Seq} -> + R = count_input(Head, Cntrs, L), + FR = fsck_objs(Bin, Head#head.keypos, Head, [], Seq), + NewState = fsck_read(FR, Pos, Fd, MaxSz, Head), + {R, fsck_input(Head, NewState, Fd, MaxSz, Cntrs)} + end + end. + +%% The ets table Cntrs is used for counting objects per size. +count_input(Head, Cntrs, L) when Head#head.version =:= 8 -> + count_input1(Cntrs, L, []); +count_input(_Head, _Cntrs, L) -> + lists:reverse(L). + +count_input1(Cntrs, [[LogSz | B] | Ts], L) -> + case catch ets:update_counter(Cntrs, LogSz, 1) of + N when is_integer(N) -> ok; + _Badarg -> true = ets:insert(Cntrs, {LogSz, 1}) + end, + count_input1(Cntrs, Ts, [B | L]); +count_input1(_Cntrs, [], L) -> + L. + +fsck_read(Pos, F, L, Seq) -> + case file:position(F, Pos) of + {ok, _} -> + read_more_bytes([], 0, Pos, F, L, Seq); + _Error -> + {done, L, Seq} + end. + +fsck_read({more, Bin, Sz, L, Seq}, Pos, F, MaxSz, Head) when Sz > MaxSz -> + FR = skip_bytes(Bin, ?BUMP, Head#head.keypos, Head, L, Seq), + fsck_read(FR, Pos, F, MaxSz, Head); +fsck_read({more, Bin, Sz, L, Seq}, Pos, F, _MaxSz, _Head) -> + read_more_bytes(Bin, Sz, Pos, F, L, Seq); +fsck_read({new, Skip, L, Seq}, Pos, F, _MaxSz, _Head) -> + NewPos = Pos + Skip, + fsck_read(NewPos, F, L, Seq). + +read_more_bytes(B, Min, Pos, F, L, Seq) -> + Max = if + Min < ?CHUNK_SIZE -> ?CHUNK_SIZE; + true -> Min + end, + case dets_utils:read_n(F, Max) of + eof -> + {done, L, Seq}; + Bin -> + NewPos = Pos + byte_size(Bin), + {cont, L, list_to_binary([B, Bin]), NewPos, Seq} + end. + +fsck_objs(Bin = <<Sz:32, Status:32, Tail/binary>>, Kp, Head, L, Seq) -> + if + Status =:= ?ACTIVE -> + Sz1 = Sz-?OHDSZ, + case Tail of + <<BinTerm:Sz1/binary, Tail2/binary>> -> + case catch bin2keybins(BinTerm, Head) of + {'EXIT', _Reason} -> + %% The whole collection of objects is skipped. + skip_bytes(Bin, ?BUMP, Kp, Head, L, Seq); + BOs -> + {NL, NSeq} = make_objects(BOs, Seq, Kp, Head, L), + Skip = ?POW(sz2pos(Sz)-1) - Sz, + skip_bytes(Tail2, Skip, Kp, Head, NL, NSeq) + end; + _ when byte_size(Tail) < Sz1 -> + {more, Bin, Sz, L, Seq} + end; + true -> + skip_bytes(Bin, ?BUMP, Kp, Head, L, Seq) + end; +fsck_objs(Bin, _Kp, _Head, L, Seq) -> + {more, Bin, 0, L, Seq}. + +make_objects([{K,BT}|Os], Seq, Kp, Head, L) when Head#head.version =:= 8 -> + LogSz = dets_v8:sz2pos(byte_size(BT)+?OHDSZ_v8), + Slot = dets_v8:db_hash(K, Head), + Obj = [LogSz | <<Slot:32, LogSz:8, BT/binary>>], + make_objects(Os, Seq, Kp, Head, [Obj | L]); +make_objects([{K,BT} | Os], Seq, Kp, Head, L) -> + Obj = make_object(Head, K, Seq, BT), + make_objects(Os, Seq+1, Kp, Head, [Obj | L]); +make_objects([], Seq, _Kp, _Head, L) -> + {L, Seq}. + +%% Inlined. +make_object(Head, Key, Seq, BT) -> + Slot = db_hash(Key, Head), + <<Slot:32, Seq:32, BT/binary>>. + +%% Inlined. +skip_bytes(Bin, Skip, Kp, Head, L, Seq) -> + case Bin of + <<_:Skip/binary, Tail/binary>> -> + fsck_objs(Tail, Kp, Head, L, Seq); + _ when byte_size(Bin) < Skip -> + {new, Skip - byte_size(Bin), L, Seq} + end. + +%%% +%%% End of repair, conversion and initialization of a dets file. +%%% + +%% -> {NewHead, ok} | throw({Head, Error}) +do_perform_save(H) -> + {ok, FreeListsPointer} = dets_utils:position(H, eof), + H1 = H#head{freelists_p = FreeListsPointer}, + {FLW, FLSize} = free_lists_to_file(H1), + FileSize = FreeListsPointer + FLSize + 4, + ok = dets_utils:write(H1, [FLW | <<FileSize:32>>]), + FileHeader = file_header(H1, FreeListsPointer, ?CLOSED_PROPERLY), + case dets_utils:debug_mode() of + true -> + TmpHead = H1#head{freelists = init_freelist(H1, true), + fixed = false}, + case + catch dets_utils:all_allocated_as_list(TmpHead) + =:= dets_utils:all_allocated_as_list(H1) + of + true -> + dets_utils:pwrite(H1, [{0, FileHeader}]); + _ -> + dets_utils:corrupt_reason(H1, {failed_to_save_free_lists, + FreeListsPointer, + TmpHead#head.freelists, + H1#head.freelists}) + end; + false -> + dets_utils:pwrite(H1, [{0, FileHeader}]) + end. + +file_header(Head, FreeListsPointer, ClosedProperly) -> + NoColls = case Head#head.no_collections of + undefined -> []; + NC -> NC + end, + L = orddict:merge(fun(_K, V1, V2) -> V1 + V2 end, + NoColls, + lists:map(fun(X) -> {X,0} end, lists:seq(4,?MAXBUD-1))), + CW = lists:map(fun({_LSz,N}) -> <<N:32>> end, L), + file_header(Head, FreeListsPointer, ClosedProperly, CW). + +file_header(Head, FreeListsPointer, ClosedProperly, NoColls) -> + Cookie = ?MAGIC, + TypeCode = dets_utils:type_to_code(Head#head.type), + Version = ?FILE_FORMAT_VERSION, + HashMethod = hash_method_to_code(Head#head.hash_bif), + H1 = <<FreeListsPointer:32, Cookie:32, ClosedProperly:32>>, + H2 = <<TypeCode:32, + Version:32, + (Head#head.m):32, + (Head#head.next):32, + (Head#head.keypos):32, + (Head#head.no_objects):32, + (Head#head.no_keys):32, + (Head#head.min_no_slots):32, + (Head#head.max_no_slots):32, + HashMethod:32, + (Head#head.n):32>>, + DigH = [H2 | NoColls], + MD5 = case Head#head.has_md5 of + true -> erlang:md5(DigH); + false -> <<0:?MD5SZ/unit:8>> + end, + [H1, DigH, MD5 | <<0:?RESERVED/unit:8>>]. + +%% Going through some trouble to avoid creating one single binary for +%% the free lists. If the free lists are huge, binary_to_term and +%% term_to_binary could otherwise stop the emulator for quite some time. + +-define(MAXFREEOBJ, 4096). +-define(ENDFREE, 12345). + +free_lists_to_file(H) -> + FL = dets_utils:get_freelists(H), + free_list_to_file(FL, H, 1, tuple_size(FL), [], 0). + +free_list_to_file(_Ftab, _H, Pos, Sz, Ws, WsSz) when Pos > Sz -> + {[Ws | <<(4+?OHDSZ):32, ?FREE:32, ?ENDFREE:32>>], WsSz+4+?OHDSZ}; +free_list_to_file(Ftab, H, Pos, Sz, Ws, WsSz) -> + Max = (?MAXFREEOBJ - 4 - ?OHDSZ) div 4, + F = fun(N, L, W, S) when N =:= 0 -> {N, L, W, S}; + (N, L, W, S) -> + {L1, N1, More} = + if + N > Max -> + {lists:sublist(L, Max), Max, + {N-Max, lists:nthtail(Max, L)}}; + true -> + {L, N, no_more} + end, + Size = N1*4 + 4 + ?OHDSZ, + Header = <<Size:32, ?FREE:32, Pos:32>>, + NW = [W, Header | L1], + case More of + no_more -> + {0, [], NW, S+Size}; + {NN, NL} -> + ok = dets_utils:write(H, NW), + {NN, NL, [], S+Size} + end + end, + {NWs,NWsSz} = dets_utils:tree_to_bin(element(Pos, Ftab), F, Max, Ws, WsSz), + free_list_to_file(Ftab, H, Pos+1, Sz, NWs, NWsSz). + +free_lists_from_file(H, Pos) -> + dets_utils:position(H#head.fptr, H#head.filename, Pos), + FL = dets_utils:empty_free_lists(), + case catch bin_to_tree([], H, start, FL, -1, []) of + {'EXIT', _} -> + throw({error, {bad_freelists, H#head.filename}}); + Reply -> + Reply + end. + +bin_to_tree(Bin, H, LastPos, Ftab, A0, L) -> + case Bin of + <<_Size:32,?FREE:32,?ENDFREE:32,_/binary>> when L =:= [] -> + Ftab; + <<_Size:32,?FREE:32,?ENDFREE:32,_/binary>> -> + setelement(LastPos, Ftab, dets_utils:list_to_tree(L)); + <<Size:32,?FREE:32,Pos:32,T/binary>> + when byte_size(T) >= Size-4-?OHDSZ -> + {NFtab, L1, A1} = + if + Pos =/= LastPos, LastPos =/= start -> + Tree = dets_utils:list_to_tree(L), + {setelement(LastPos, Ftab, Tree), [], -1}; + true -> + {Ftab, L, A0} + end, + {NL, B2, A2} = bin_to_tree1(T, Size-?OHDSZ-4, A1, L1), + bin_to_tree(B2, H, Pos, NFtab, A2, NL); + _ -> + Bin2 = dets_utils:read_n(H#head.fptr, ?MAXFREEOBJ), + bin_to_tree(list_to_binary([Bin | Bin2]), H, LastPos, Ftab, A0, L) + end. + +bin_to_tree1(<<A1:32,A2:32,A3:32,A4:32,T/binary>>, Size, A, L) + when Size >= 16, A < A1, A1 < A2, A2 < A3, A3 < A4 -> + bin_to_tree1(T, Size-16, A4, [A4, A3, A2, A1 | L]); +bin_to_tree1(<<A1:32,T/binary>>, Size, A, L) when Size >= 4, A < A1 -> + bin_to_tree1(T, Size - 4, A1, [A1 | L]); +bin_to_tree1(B, 0, A, L) -> + {L, B, A}. + +%% -> [term()] | throw({Head, Error}) +slot_objs(H, Slot) when Slot >= H#head.next -> + '$end_of_table'; +slot_objs(H, Slot) -> + {ok, _Pointer, Objects} = slot_objects(H, Slot), + Objects. + +%% Inlined. +h(I, phash2) -> erlang:phash2(I); % -> [0..2^27-1] +h(I, phash) -> erlang:phash(I, ?BIG) - 1. + +db_hash(Key, Head) when Head#head.hash_bif =:= phash2 -> + H = erlang:phash2(Key), + Hash = ?REM2(H, Head#head.m), + if + Hash < Head#head.n -> + ?REM2(H, Head#head.m2); % H rem (2 * m) + true -> + Hash + end; +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. + +hash_method_to_code(phash2) -> ?PHASH2; +hash_method_to_code(phash) -> ?PHASH. + +code_to_hash_method(?PHASH2) -> phash2; +code_to_hash_method(?PHASH) -> phash; +code_to_hash_method(_) -> undefined. + +no_slots(Head) -> + {Head#head.min_no_slots, Head#head.next, Head#head.max_no_slots}. + +table_parameters(Head) -> + case Head#head.no_collections of + undefined -> + undefined; % Version 9(a) + CL -> + NoColls0 = lists:foldl(fun({_,0}, A) -> A; + (E, A) -> [E | A] + end, [], CL), + NoColls = lists:reverse(NoColls0), + #?HASH_PARMS{file_format_version = Head#head.version, + bchunk_format_version = ?BCHUNK_FORMAT_VERSION, + file = filename:basename(Head#head.filename), + type = Head#head.type, + keypos = Head#head.keypos, + hash_method = hash_method_to_code(Head#head.hash_bif), + n = Head#head.n, m = Head#head.m, + next = Head#head.next, + min = Head#head.min_no_slots, + max = Head#head.max_no_slots, + no_objects = Head#head.no_objects, + no_keys = Head#head.no_keys, no_colls = NoColls} + end. + +%% Allow quite a lot when reading object collections. +-define(MAXCOLL, (10 * ?CHUNK_SIZE)). + +%% Re-hashing a segment, starting with SlotStart. +%% +%% On the average, half of the keys of the slot are put in a new slot. +%% If the old slot is i, then the new slot is i+m. The new slots +%% reside in a newly allocated segment. +%% +%% -> {NewHead, ok} | throw({Head, Error}) +re_hash(Head, SlotStart) -> + FromSlotPos = slot_position(SlotStart), + ToSlotPos = slot_position(SlotStart + Head#head.m), + RSpec = [{FromSlotPos, 4 * ?SEGSZ}], + {ok, [FromBin]} = dets_utils:pread(RSpec, Head), + split_bins(FromBin, Head, FromSlotPos, ToSlotPos, [], [], 0). + +split_bins(<<>>, Head, _Pos1, _Pos2, _ToRead, _L, 0) -> + {Head, ok}; +split_bins(<<>>, Head, Pos1, Pos2, ToRead, L, _SoFar) -> + re_hash_write(Head, ToRead, L, Pos1, Pos2); +split_bins(FB, Head, Pos1, Pos2, ToRead, L, SoFar) -> + <<Sz1:32, P1:32, FT/binary>> = FB, + <<B1:?OHDSZ/binary, _/binary>> = FB, + NSoFar = SoFar + Sz1, + NPos1 = Pos1 + ?SZOBJP*4, + NPos2 = Pos2 + ?SZOBJP*4, + if + NSoFar > ?MAXCOLL, ToRead =/= [] -> + {NewHead, ok} = re_hash_write(Head, ToRead, L, Pos1, Pos2), + split_bins(FB, NewHead, Pos1, Pos2, [], [], 0); + Sz1 =:= 0 -> + E = {skip,B1}, + split_bins(FT, Head, NPos1, NPos2, ToRead, [E | L], NSoFar); + true -> + E = {Sz1,P1,B1,Pos1,Pos2}, + NewToRead = [{P1,Sz1} | ToRead], + split_bins(FT, Head, NPos1, NPos2, NewToRead, [E | L], NSoFar) + end. + +re_hash_write(Head, ToRead, L, Pos1, Pos2) -> + check_pread2_arg(ToRead, Head), + {ok, Bins} = dets_utils:pread(ToRead, Head), + Z = <<0:32, 0:32>>, + {Head1, BinFS, BinTS, WsB} = re_hash_slots(Bins, L, Head, Z, [],[],[]), + WPos1 = Pos1 - ?SZOBJP*4*length(L), + WPos2 = Pos2 - ?SZOBJP*4*length(L), + ToWrite = [{WPos1,BinFS}, {WPos2, BinTS} | WsB], + dets_utils:pwrite(Head1, ToWrite). + +re_hash_slots(Bins, [{skip,B1} | L], Head, Z, BinFS, BinTS, WsB) -> + re_hash_slots(Bins, L, Head, Z, [B1 | BinFS], [Z | BinTS], WsB); +re_hash_slots([FB | Bins], [E | L], Head, Z, BinFS, BinTS, WsB) -> + {Sz1,P1,B1,Pos1,Pos2} = E, + KeyObjs = case catch per_key(Head, FB) of + {'EXIT', _Error} -> + Bad = dets_utils:bad_object(re_hash_slots, {FB, E}), + throw(dets_utils:corrupt_reason(Head, Bad)); + Else -> + Else + end, + case re_hash_split(KeyObjs, Head, [], 0, [], 0) of + {_KL, _KSz, [], 0} -> + Sz1 = _KSz + ?OHDSZ, + re_hash_slots(Bins, L, Head, Z, [B1 | BinFS], [Z | BinTS], WsB); + {[], 0, _ML, _MSz} -> %% Optimization. + Sz1 = _MSz + ?OHDSZ, + re_hash_slots(Bins, L, Head, Z, [Z | BinFS], [B1 | BinTS], WsB); + {KL, KSz, ML, MSz} when KL =/= [], KSz > 0, ML =/= [], MSz > 0 -> + {Head1, FS1, Ws1} = + updated(Head, P1, Sz1, KSz, Pos1, KL, true, foo, bar), + {NewHead, [{Pos2,Bin2}], Ws2} = + updated(Head1, 0, 0, MSz, Pos2, ML, true, foo, bar), + NewBinFS = case FS1 of + [{Pos1,Bin1}] -> [Bin1 | BinFS]; + [] -> [B1 | BinFS] % cannot happen + end, + NewBinTS = [Bin2 | BinTS], + NewWsB = Ws2 ++ Ws1 ++ WsB, + re_hash_slots(Bins, L, NewHead, Z, NewBinFS, NewBinTS, NewWsB) + end; +re_hash_slots([], [], Head, _Z, BinFS, BinTS, WsB) -> + {Head, BinFS, BinTS, lists:reverse(WsB)}. + +re_hash_split([E | KeyObjs], Head, KL, KSz, ML, MSz) -> + {Key,Sz,Bin,_Item,_Objs} = E, + New = h(Key, Head#head.hash_bif) rem Head#head.m2, % h(key) rem (m * 2) + if + New >= Head#head.m -> + re_hash_split(KeyObjs, Head, KL, KSz, [Bin | ML], MSz + Sz); + true -> + re_hash_split(KeyObjs, Head, [Bin | KL], KSz + Sz, ML, MSz) + end; +re_hash_split([], _Head, KL, KSz, ML, MSz) -> + {lists:reverse(KL), KSz, lists:reverse(ML), MSz}. + +%% -> {NewHead, [LookedUpObject], pwrite_list()} | throw({NewHead, Error}) +write_cache(Head) -> + C = Head#head.cache, + case dets_utils:is_empty_cache(C) of + true -> {Head, [], []}; + false -> + {NewC, MaxInserts, PerKey} = dets_utils:reset_cache(C), + %% MaxNoInsertedKeys is an upper limit on the number of new keys. + MaxNoInsertedKeys = erlang:min(MaxInserts, length(PerKey)), + Head1 = Head#head{cache = NewC}, + case may_grow(Head1, MaxNoInsertedKeys, once) of + {Head2, ok} -> + eval_work_list(Head2, PerKey); + HeadError -> + throw(HeadError) + end + end. + +%% -> {NewHead, ok} | {NewHead, Error} +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 >= Head#head.max_no_slots -> + {Head, ok}; +may_grow(Head, N, How) -> + Extra = erlang:min(2*?SEGSZP, Head#head.no_keys + N - Head#head.next), + case catch may_grow1(Head, Extra, How) of + {error, _Reason} = Error -> % alloc may throw error + dets_utils:corrupt(Head, Error); + {NewHead, Reply} when is_record(Head, head) -> + {NewHead, Reply} + end. + +may_grow1(Head, Extra, many_times) when Extra > ?SEGSZP -> + 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) when Head#head.next >= Head#head.max_no_slots -> + {Head, ok}; +grow(Head, Extra, SegZero) -> + #head{n = N, next = Next, m = M} = Head, + SegNum = Next div ?SEGSZP, + {Head0, W, Ws1} = allocate_segment(Head, SegZero, SegNum), + %% re_hash/2 will overwrite the segment, but initialize it anyway... + {Head1, ok} = dets_utils:pwrite(Head0, [W | Ws1]), + %% If re_hash fails, segp_cache has been called, but it does not matter. + {Head2, ok} = re_hash(Head1, N), + NewHead = + if + N + ?SEGSZP =:= M -> + Head2#head{n = 0, next = Next + ?SEGSZP, m = 2 * M, m2 = 4 * M}; + true -> + Head2#head{n = N + ?SEGSZP, next = Next + ?SEGSZP} + end, + true = hash_invars(NewHead), + grow(NewHead, Extra - ?SEGSZP, SegZero). + +hash_invars(H) -> + hash_invars(H#head.n, H#head.m, H#head.next, H#head.min_no_slots, + H#head.max_no_slots). + +-define(M8(X), (((X) band (?SEGSZP - 1)) =:= 0)). +hash_invars(N, M, Next, Min, Max) -> + ?M8(N) and ?M8(M) and ?M8(Next) and ?M8(Min) and ?M8(Max) + and (0 =< N) and (N =< M) and (N =< 2*Next) and (M =< Next) + and (Next =< 2*M) and (0 =< Min) and (Min =< Next) and (Next =< Max) + and (Min =< M). + +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) -> + case catch slot_objects(H, Slot) of + {ok, Pointer, Objects} -> + case lists:member(Obj, Objects) of + true -> {ok, Pointer}; + false -> false + end; + _ -> false + end. + +%% -> {ok, BucketP, Objects} | throw({Head, Error}) +slot_objects(Head, Slot) -> + SlotPos = slot_position(Slot), + MaxSize = maxobjsize(Head), + case dets_utils:ipread(Head, SlotPos, MaxSize) of + {ok, {BucketSz, Pointer, <<BucketSz:32, _St:32, KeysObjs/binary>>}} -> + case catch bin2objs(KeysObjs, Head#head.type, []) of + {'EXIT', _Error} -> + Bad = dets_utils:bad_object(slot_objects, + {SlotPos, KeysObjs}), + throw(dets_utils:corrupt_reason(Head, Bad)); + Objs when is_list(Objs) -> + {ok, Pointer, lists:reverse(Objs)} + end; + [] -> + {ok, 0, []}; + BadRead -> % eof or bad badly formed binary + Bad = dets_utils:bad_object(slot_objects, {SlotPos, BadRead}), + throw(dets_utils:corrupt_reason(Head, Bad)) + end. + +%%% +%%% Cache routines depending on the dets file format. +%%% + +%% -> {Head, [LookedUpObject], pwrite_list()} | throw({Head, Error}) +eval_work_list(Head, [{Key,[{_Seq,{lookup,Pid}}]}]) -> + SlotPos = slot_position(db_hash(Key, Head)), + MaxSize = maxobjsize(Head), + Objs = case dets_utils:ipread(Head, SlotPos, MaxSize) of + {ok, {_BucketSz, _Pointer, Bin}} -> + case catch per_key(Head, Bin) of + {'EXIT', _Error} -> + Bad = dets_utils:bad_object(eval_work_list, + {SlotPos, Bin}), + throw(dets_utils:corrupt_reason(Head, Bad)); + KeyObjs when is_list(KeyObjs) -> + case dets_utils:mkeysearch(Key, 1, KeyObjs) of + false -> + []; + {value, {Key,_KS,_KB,O,Os}} -> + case catch binobjs2terms(Os) of + {'EXIT', _Error} -> + Bad = dets_utils:bad_object + (eval_work_list, + {SlotPos, Bin, KeyObjs}), + throw(dets_utils:corrupt_reason + (Head, Bad)); + Terms when is_list(Terms) -> + get_objects([O | Terms]) + end + end + end; + [] -> + []; + BadRead -> % eof or bad badly formed binary + Bad = dets_utils:bad_object(eval_work_list, + {SlotPos, BadRead}), + throw(dets_utils:corrupt_reason(Head, Bad)) + end, + {Head, [{Pid,Objs}], []}; +eval_work_list(Head, PerKey) -> + SWLs = tag_with_slot(PerKey, Head, []), + P1 = dets_utils:family(SWLs), + {PerSlot, SlotPositions} = remove_slot_tag(P1, [], []), + {ok, Bins} = dets_utils:pread(SlotPositions, Head), + read_buckets(PerSlot, SlotPositions, Bins, Head, [], [], [], [], 0, 0, 0). + +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), ?SEGOBJSZ} | SPs]); +remove_slot_tag([], Ls, SPs) -> + {Ls, SPs}. + +read_buckets([WLs | SPs], [{P1,_8} | Ss], [<<_Zero:32,P2:32>> | Bs], Head, + PWLs, ToRead, LU, Ws, NoObjs, NoKeys, SoFar) when P2 =:= 0 -> + {NewHead, NLU, NWs, No, KNo} = + eval_bucket_keys(WLs, P1, 0, 0, [], Head, Ws, LU), + NewNoObjs = No + NoObjs, + NewNoKeys = KNo + NoKeys, + read_buckets(SPs, Ss, Bs, NewHead, PWLs, ToRead, NLU, NWs, + NewNoObjs, NewNoKeys, SoFar); +read_buckets([WorkLists| SPs], [{P1,_8} | Ss], [<<Size:32,P2:32>> | Bs], Head, + PWLs, ToRead, LU, Ws, NoObjs, NoKeys, SoFar) + when SoFar + Size < ?MAXCOLL; ToRead =:= [] -> + NewToRead = [{P2, Size} | ToRead], + NewPWLs = [{P2,P1,WorkLists} | PWLs], + NewSoFar = SoFar + Size, + read_buckets(SPs, Ss, Bs, Head, NewPWLs, NewToRead, LU, Ws, + NoObjs, NoKeys, NewSoFar); +read_buckets(SPs, Ss, Bs, Head, PWLs0, ToRead0, LU, Ws, NoObjs, NoKeys, SoFar) + when SoFar > 0 -> + %% It pays off to sort the positions. The seek times are reduced, + %% at least if the file blocks are reasonably contiguous, as is + %% often the case. + PWLs = lists:keysort(1, PWLs0), + ToRead = lists:keysort(1, ToRead0), + check_pread2_arg(ToRead, Head), + {ok, Bins} = dets_utils:pread(ToRead, Head), + case catch eval_buckets(Bins, PWLs, Head, LU, Ws, 0, 0) of + {ok, NewHead, NLU, [], 0, 0} -> + read_buckets(SPs, Ss, Bs, NewHead, [], [], NLU, [], + NoObjs, NoKeys, 0); + {ok, Head1, NLU, NWs, No, KNo} -> + NewNoObjs = NoObjs + No, + NewNoKeys = NoKeys + KNo, + %% It does not seem to reduce seek times to sort positions + %% when writing (maybe because it takes several calls to + %% write_cache/1 to fill the file system's buffer cache). + {NewHead, ok} = dets_utils:pwrite(Head1, lists:reverse(NWs)), + read_buckets(SPs, Ss, Bs, NewHead, [], [], NLU, [], + NewNoObjs, NewNoKeys, 0); + Error -> + Bad = dets_utils:bad_object(read_buckets, {Bins, Error}), + throw(dets_utils:corrupt_reason(Head, Bad)) + end; +read_buckets([], [], [], Head, [], [], LU, Ws, NoObjs, NoKeys, 0) -> + {NewHead, NWs} = update_no_keys(Head, Ws, NoObjs, NoKeys), + {NewHead, LU, lists:reverse(NWs)}. + +eval_buckets([Bin | Bins], [SP | SPs], Head, LU, Ws, NoObjs, NoKeys) -> + {Pos, P1, WLs} = SP, + KeyObjs = per_key(Head, Bin), + {NewHead, NLU, NWs, No, KNo} = + eval_bucket_keys(WLs, P1, Pos, byte_size(Bin), KeyObjs, Head,Ws,LU), + eval_buckets(Bins, SPs, NewHead, NLU, NWs, NoObjs + No, NoKeys + KNo); +eval_buckets([], [], Head, LU, Ws, NoObjs, NoKeys) -> + {ok, Head, LU, Ws, NoObjs, NoKeys}. + +eval_bucket_keys(WLs, SlotPos, Pos, OldSize, KeyObjs, Head, Ws, LU) -> + {NLU, Bins, BSize, No, KNo, Ch} = + eval_slot(WLs, KeyObjs, Head#head.type, LU, [], 0, 0, 0, false), + {NewHead, W1, W2} = + updated(Head, Pos, OldSize, BSize, SlotPos, Bins, Ch, No, KNo), + {NewHead, NLU, W2++W1++Ws, No, KNo}. + +updated(Head, Pos, OldSize, BSize, SlotPos, Bins, Ch, DeltaNoOs, DeltaNoKs) -> + BinsSize = BSize + ?OHDSZ, + if + Pos =:= 0, BSize =:= 0 -> + {Head, [], []}; + Pos =:= 0, BSize > 0 -> + {Head1, NewPos, FPos} = dets_utils:alloc(Head, adjsz(BinsSize)), + NewHead = one_bucket_added(Head1, FPos-1), + W1 = {NewPos, [<<BinsSize:32, ?ACTIVE:32>> | Bins]}, + W2 = {SlotPos, <<BinsSize:32, NewPos:32>>}, + {NewHead, [W2], [W1]}; + Pos =/= 0, BSize =:= 0 -> + {Head1, FPos} = dets_utils:free(Head, Pos, adjsz(OldSize)), + NewHead = one_bucket_removed(Head1, FPos-1), + W1 = {Pos+?STATUS_POS, <<?FREE:32>>}, + W2 = {SlotPos, <<0:32, 0:32>>}, + {NewHead, [W2], [W1]}; + Pos =/= 0, BSize > 0, Ch =:= false -> + {Head, [], []}; + Pos =/= 0, BSize > 0 -> + %% Doubtful. The scan function has to be careful since + %% partly scanned objects may be overwritten. + Overwrite0 = if + OldSize =:= BinsSize -> same; + true -> sz2pos(OldSize) =:= sz2pos(BinsSize) + end, + Overwrite = if + Head#head.fixed =/= false -> + %% Make sure that if the table is + %% fixed, nothing is overwritten, + %% unless the number of objects and + %% the number of keys remain the same. + %% This is used by bchunk, which + %% assumes that it traverses exactly + %% the same number of objects and keys + %% (and collections) as were present + %% when chunking started (the table + %% must have been fixed). + (Overwrite0 =/= false) and + (DeltaNoOs =:= 0) and (DeltaNoKs =:= 0); + true -> + Overwrite0 + end, + if + Overwrite =:= same -> + W1 = {Pos+?OHDSZ, Bins}, + {Head, [], [W1]}; + Overwrite -> + W1 = {Pos, [<<BinsSize:32, ?ACTIVE:32>> | Bins]}, + %% Pos is already there, but return {SlotPos, <8 bytes>}. + W2 = {SlotPos, <<BinsSize:32, Pos:32>>}, + {Head, [W2], [W1]}; + true -> + {Head1, FPosF} = dets_utils:free(Head, Pos, adjsz(OldSize)), + {Head2, NewPos, FPosA} = + dets_utils:alloc(Head1, adjsz(BinsSize)), + Head3 = one_bucket_added(Head2, FPosA-1), + NewHead = one_bucket_removed(Head3, FPosF-1), + W0 = {NewPos, [<<BinsSize:32, ?ACTIVE:32>> | Bins]}, + W2 = {SlotPos, <<BinsSize:32, NewPos:32>>}, + W1 = if + Pos =/= NewPos -> + %% W0 first. + [W0, {Pos+?STATUS_POS, <<?FREE:32>>}]; + true -> + [W0] + end, + {NewHead, [W2], W1} + end + end. + +one_bucket_added(H, _Log2) when H#head.no_collections =:= undefined -> + H; +one_bucket_added(H, Log2) when H#head.maxobjsize >= Log2 -> + NewNoColls = orddict:update_counter(Log2, 1, H#head.no_collections), + H#head{no_collections = NewNoColls}; +one_bucket_added(H, Log2) -> + NewNoColls = orddict:update_counter(Log2, 1, H#head.no_collections), + H#head{no_collections = NewNoColls, maxobjsize = Log2}. + +one_bucket_removed(H, _FPos) when H#head.no_collections =:= undefined -> + H; +one_bucket_removed(H, Log2) when H#head.maxobjsize > Log2 -> + NewNoColls = orddict:update_counter(Log2, -1, H#head.no_collections), + H#head{no_collections = NewNoColls}; +one_bucket_removed(H, Log2) when H#head.maxobjsize =:= Log2 -> + NewNoColls = orddict:update_counter(Log2, -1, H#head.no_collections), + MaxObjSize = max_objsize(NewNoColls), + H#head{no_collections = NewNoColls, maxobjsize = MaxObjSize}. + +eval_slot([{Key,Commands} | WLs] = WLs0, [{K,KS,KB,O,Os} | KOs1]=KOs, + Type, LU, Ws, No, KNo,BSz, Ch) -> + case dets_utils:cmp(K, Key) of + 0 -> + Old = [O | binobjs2terms(Os)], + {NLU, NWs, Sz, No1, KNo1, NCh} = + eval_key(Key, Commands, Old, Type, KB, KS, LU, Ws, Ch), + eval_slot(WLs, KOs1, Type, NLU, NWs, No1 + No, + KNo1 + KNo, Sz + BSz, NCh); + -1 -> + eval_slot(WLs0, KOs1, Type, LU, [Ws | KB], No, + KNo, KS + BSz, Ch); + 1 -> + {NLU, NWs, Sz, No1, KNo1, NCh} = + eval_key(Key, Commands, [], Type, [], 0, LU, Ws, Ch), + eval_slot(WLs, KOs, Type, NLU, NWs, No1 + No, + KNo1 + KNo, Sz + BSz, NCh) + end; +eval_slot([{Key,Commands} | WLs], [], Type, LU, Ws, No, KNo,BSz, Ch) -> + {NLU, NWs, Sz, No1, KNo1, NCh} = + eval_key(Key, Commands, [], Type, [], 0, LU, Ws, Ch), + eval_slot(WLs, [], Type, NLU, NWs, No1 + No, KNo1 + KNo, Sz + BSz, NCh); +eval_slot([], [{_Key,Size,KeyBin,_,_} | KOs], Type, LU, Ws, No, KNo,BSz, Ch) -> + eval_slot([], KOs, Type, LU, [Ws | KeyBin], No, KNo, Size + BSz, Ch); +eval_slot([], [], _Type, LU, Ws, No, KNo, BSz, Ch) -> + {LU, Ws, BSz, No, KNo, Ch}. + +eval_key(_K, [{_Seq,{lookup,Pid}}], [], _Type, _KeyBin, _KeySz, LU, Ws, Ch) -> + NLU = [{Pid, []} | LU], + {NLU, Ws, 0, 0, 0, Ch}; +eval_key(_K, [{_Seq,{lookup,Pid}}], Old0, _Type, KeyBin, KeySz, LU, Ws, Ch) -> + Old = lists:keysort(2, Old0), % sort on sequence number + Objs = get_objects(Old), + NLU = [{Pid, Objs} | LU], + {NLU, [Ws | KeyBin], KeySz, 0, 0, Ch}; +eval_key(K, Comms, Orig, Type, KeyBin, KeySz, LU, Ws, Ch) -> + Old = dets_utils:msort(Orig), + case eval_key1(Comms, [], Old, Type, K, LU, Ws, 0, Orig) of + {ok, NLU} when Old =:= [] -> + {NLU, Ws, 0, 0, 0, Ch}; + {ok, NLU} -> + {NLU, [Ws | KeyBin], KeySz, 0, 0, Ch}; + {NLU, NWs, NSz, No} when Old =:= [], NSz > 0 -> + {NLU, NWs, NSz, No, 1, true}; + {NLU, NWs, NSz, No} when Old =/= [], NSz =:= 0 -> + {NLU, NWs, NSz, No, -1, true}; + {NLU, NWs, NSz, No} -> + {NLU, NWs, NSz, No, 0, true} + end. + +%% First find 'delete_key' and 'lookup' commands, and handle the 'set' type. +eval_key1([{_Seq,{insert,Term}} | L], Cs, [{Term,_,_}] = Old, Type=set, K, + LU, Ws, No, Orig) -> + eval_key1(L, Cs, Old, Type, K, LU, Ws, No, Orig); +eval_key1([{Seq,{insert,Term}} | L], Cs, Old, Type=set, K, LU, Ws, No, Orig) + -> + NNo = No + 1 - length(Old), + eval_key1(L, Cs, [{Term,Seq,insert}], Type, K, LU, Ws, NNo, Orig); +eval_key1([{_Seq,{lookup,Pid}} | L], Cs, Old, Type, Key, LU, Ws, No, Orig) -> + {ok, New0, NewNo} = eval_comms(Cs, Old, Type, No), + New = lists:keysort(2, New0), % sort on sequence number + Objs = get_objects(New), + NLU = [{Pid, Objs} | LU], + if + L =:= [] -> + eval_end(New, NLU, Type, Ws, NewNo, Orig); + true -> + NewOld = dets_utils:msort(New), + eval_key1(L, [], NewOld, Type, Key, NLU, Ws, NewNo, Orig) + end; +eval_key1([{_Seq,delete_key} | L], _Cs, Old, Type, K, LU, Ws, No, Orig) -> + NewNo = No - length(Old), + eval_key1(L, [], [], Type, K, LU, Ws, NewNo, Orig); +eval_key1([{_Seq,{delete_object,Term}} | L], Cs, [{Term,_,_}], Type=set, K, + LU, Ws, No, Orig) -> + eval_key1(L, Cs, [], Type, K, LU, Ws, No-1, Orig); +eval_key1([{_Seq,{delete_object,_T}}| L], Cs, Old1, Type=set, K, LU, + Ws, No, Orig) -> + eval_key1(L, Cs, Old1, Type, K, LU, Ws, No, Orig); +eval_key1([{Seq,{Comm,Term}} | L], Cs, Old, Type, K, LU, Ws, No, Orig) + when Type =/= set -> + eval_key1(L, [{Term,Seq,Comm} | Cs], Old, Type, K, LU, Ws, No, Orig); +eval_key1([], Cs, Old, Type=set, _Key, LU, Ws, No, Orig) -> + [] = Cs, + eval_end(Old, LU, Type, Ws, No, Orig); +eval_key1([], Cs, Old, Type, _Key, LU, Ws, No, Orig) -> + {ok, New, NewNo} = eval_comms(Cs, Old, Type, No), + eval_end(New, LU, Type, Ws, NewNo, Orig). + +eval_comms([], L, _Type=set, No) -> + {ok, L, No}; +eval_comms(Cs, Old, Type, No) -> + Commands = dets_utils:msort(Cs), + case Type of + bag -> eval_bag(Commands, Old, [], No); + duplicate_bag -> eval_dupbag(Commands, Old, [], No) + end. + +eval_end(New0, LU, Type, Ws, NewNo, Orig) -> + New = lists:keysort(2, New0), % sort on sequence number + NoChange = if + length(New) =/= length(Orig) -> false; + true -> + same_terms(Orig, New) + end, + if + NoChange -> + %% The key's objects have not changed. + {ok, LU}; + New =:= [] -> + {LU, Ws, 0, NewNo}; + true -> + {Ws1, Sz} = make_bins(New, [], 0), + if + Type =:= set -> + {LU, [Ws | Ws1], Sz, NewNo}; + true -> + NSz = Sz + 4, + {LU, [Ws, <<NSz:32>> | Ws1], NSz, NewNo} + end + end. + +same_terms([E1 | L1], [E2 | L2]) when element(1, E1) =:= element(1, E2) -> + same_terms(L1, L2); +same_terms([], []) -> + true; +same_terms(_L1, _L2) -> + false. + +make_bins([{_Term,_Seq,B} | L], W, Sz) when is_binary(B) -> + make_bins(L, [W | B], Sz + byte_size(B)); +make_bins([{Term,_Seq,insert} | L], W, Sz) -> + B = term_to_binary(Term), + BSize = byte_size(B) + 4, + make_bins(L, [W, [<<BSize:32>> | B]], Sz + BSize); +make_bins([], W, Sz) -> + {W, Sz}. + +get_objects([{T,_S,_BT} | L]) -> + [T | get_objects(L)]; +get_objects([]) -> + []. + +eval_bag([{Term1,_S1,Op}=N | L]=L0, [{Term2,_,_}=O | Old]=Old0, New, No) -> + case {Op, dets_utils:cmp(Term1, Term2)} of + {delete_object, -1} -> + eval_bag(L, Old0, New, No); + {insert, -1} -> + bag_object(L, Old0, New, No, [N], Term1); + {delete_object, 0} -> + bag_object(L, Old, New, No-1, [], Term1); + {insert, 0} -> + bag_object(L, Old, New, No-1, [N], Term1); + {_, 1} -> + eval_bag(L0, Old, [O | New], No) + end; +eval_bag([{_Term1,_Seq1,delete_object} | L], []=Old, New, No) -> + eval_bag(L, Old, New, No); +eval_bag([{Term,_Seq1,insert} = N | L], []=Old, New, No) -> + bag_object(L, Old, New, No, [N], Term); +eval_bag([]=L, [O | Old], New, No) -> + eval_bag(L, Old, [O | New], No); +eval_bag([], [], New, No) -> + {ok, New, No}. + +bag_object([{Term,_,insert} = N | L], Old, New, No, _N, Term) -> + bag_object(L, Old, New, No, [N], Term); +bag_object([{Term,_,delete_object} | L], Old, New, No, _N, Term) -> + bag_object(L, Old, New, No, [], Term); +bag_object(L, Old, New, No, [], _Term) -> + eval_bag(L, Old, New, No); +bag_object(L, Old, New, No, [N], _Term) -> + eval_bag(L, Old, [N | New], No+1). + +eval_dupbag([{Term1,_S1,Op}=N | L]=L0, [{Term2,_,_}=O | Old]=Old0, New, No) -> + case {Op, dets_utils:cmp(Term1, Term2)} of + {delete_object, -1} -> + eval_dupbag(L, Old0, New, No); + {insert, -1} -> + dup_object(L, Old0, New, No+1, Term1, [N]); + {_, 0} -> + old_dup_object(L0, Old, New, No, Term1, [O]); + {_, 1} -> + eval_dupbag(L0, Old, [O | New], No) + end; +eval_dupbag([{_Term1,_Seq1,delete_object} | L], []=Old, New, No) -> + eval_dupbag(L, Old, New, No); +eval_dupbag([{Term,_Seq1,insert} = N | L], []=Old, New, No) -> + dup_object(L, Old, New, No+1, Term, [N]); +eval_dupbag([]=L, [O | Old], New, No) -> + eval_dupbag(L, Old, [O | New], No); +eval_dupbag([], [], New, No) -> + {ok, New, No}. + +old_dup_object(L, [{Term,_,_} = Obj | Old], New, No, Term, N) -> + old_dup_object(L, Old, New, No, Term, [Obj | N]); +old_dup_object(L, Old, New, No, Term, N) -> + dup_object(L, Old, New, No, Term, N). + +dup_object([{Term,_,insert} = Obj | L], Old, New, No, Term, Q) -> + dup_object(L, Old, New, No+1, Term, [Obj | Q]); +dup_object([{Term,_Seq,delete_object} | L], Old, New, No, Term, Q) -> + %% All objects are deleted. + NewNo = No - length(Q), + dup_object(L, Old, New, NewNo, Term, []); +dup_object(L, Old, New, No, _Term, Q) -> + eval_dupbag(L, Old, Q ++ New, No). + +%% Update no_keys on the file too, if the number of segments that +%% dets:fsck/6 uses for estimate has changed. +update_no_keys(Head, Ws, 0, 0) -> {Head, Ws}; +update_no_keys(Head, Ws, DeltaObjects, DeltaKeys) -> + NoKeys = Head#head.no_keys, + NewNoKeys = NoKeys + DeltaKeys, + NewNoObject = Head#head.no_objects + DeltaObjects, + NewHead = Head#head{no_objects = NewNoObject, no_keys = NewNoKeys}, + NWs = + if + NewNoKeys > NewHead#head.max_no_slots -> + Ws; + NoKeys div ?SEGSZP =:= NewNoKeys div ?SEGSZP -> + Ws; + true -> + [{0, file_header(NewHead, 0, ?NOT_PROPERLY_CLOSED)} | Ws] + end, + {NewHead, NWs}. + +slot_position(S) -> + SegNo = ?SLOT2SEG(S), % S div ?SEGSZP + PartPos = ?SEGARRADDR(?SEG2SEGARRPART(SegNo)), % SegNo div ?SEGPARTSZ + Part = get_arrpart(PartPos), + Pos = ?SEGPARTADDR(Part, SegNo), + get_segp(Pos) + (?SEGOBJSZ * ?REM2(S, ?SEGSZP)). + +check_pread2_arg([{_Pos,Sz}], Head) when Sz > ?MAXCOLL -> + case check_pread_arg(Sz, Head) of + true -> + ok; + false -> + Bad = dets_utils:bad_object(check_pread2_arg, Sz), + throw(dets_utils:corrupt_reason(Head, Bad)) + end; +check_pread2_arg(_ToRead, _Head) -> + ok. + +check_pread_arg(Sz, Head) when Sz > ?MAXCOLL -> + maxobjsize(Head) >= Sz; +check_pread_arg(_Sz, _Head) -> + true. + +%% Inlined. +segp_cache(Pos, Segment) -> + put(Pos, Segment). + +%% Inlined. +get_segp(Pos) -> + get(Pos). + +arrpart_cache(Pos, ArrPart) -> + put(Pos, ArrPart). + +%% Inlined. +get_arrpart(Pos) -> + get(Pos). + +sz2pos(N) -> + 1 + dets_utils:log2(N). + +%% Inlined. Compensates for the bug in dets_utils:sz2pos/1. +adjsz(N) -> + N-1. + +%% Inlined. +maxobjsize(Head) when Head#head.maxobjsize =:= undefined -> + ?POW(32); +maxobjsize(Head) -> + ?POW(Head#head.maxobjsize). + +scan_objs(Head, Bin, From, To, L, Ts, R, Type) -> + case catch scan_skip(Bin, From, To, L, Ts, R, Type, 0) of + {'EXIT', _Reason} -> + bad_object; + Reply = {more, _From1, _To, _L, _Ts, _R, Size} when Size > ?MAXCOLL -> + case check_pread_arg(Size, Head) of + true -> Reply; + false -> bad_object + end; + Reply -> + Reply + end. + +scan_skip(Bin, From, To, L, Ts, R, Type, Skip) -> + From1 = From + Skip, + case Bin of + _ when From1 >= To -> + if + From1 > To; L =:= <<>> -> + {more, From1, To, L, Ts, R, 0}; + true -> + <<From2:32, To1:32, L1/binary>> = L, + Skip1 = From2 - From, + scan_skip(Bin, From, To1, L1, Ts, R, Type, Skip1) + end; + <<_:Skip/binary, _Size:32, St:32, _Sz:32, KO/binary>> + when St =/= ?ACTIVE, St =/= ?FREE -> + %% Neither ?ACTIVE nor ?FREE is a multiple of ?BUMP and + %% thus cannot be found in segments or segment array + %% parts. + scan_skip(KO, From1+12, To, L, Ts, R, Type, ?ACTUAL_SEG_SIZE-12); + <<_:Skip/binary, Size:32, _St:32, Sz:32, KO/binary>> + when Size-12 =< byte_size(KO) -> + %% St = ?FREE means that the object was deleted after + %% scanning started + bin2bins(KO, From1+12, To, L, Ts, R, Type, Size, Sz); + <<_:Skip/binary, Size:32, _St:32, _Sz:32, _KO/binary>> -> + {more, From1, To, L, Ts, R, Size}; + _ when Skip >= 0 -> + {more, From1, To, L, Ts, R, 0} + end. + +%% Appends objects in reversed order. All objects of the slot are +%% extracted. Note that binary_to_term/1 ignores garbage at the end. +bin2bins(Bin, From, To, L, Ts, R, Type=set, Size, ObjSz0) -> + ObjsSz1 = Size - ObjSz0, + if + ObjsSz1 =:= ?OHDSZ -> + slot_end(Bin, From, To, L, [Bin | Ts], R, Type, Size, 1); + true -> + ObjSz = ObjSz0-4, + <<_:ObjSz/binary, NObjSz:32, T/binary>> = Bin, + bins_set(T, From, To, L, [Bin | Ts], R, Type, Size, 2, + NObjSz, ObjsSz1-NObjSz, Bin) + end; +bin2bins(<<ObjSz:32, Bin/binary>> = KO, From, To, L, Ts, R, Type, Size, Sz) -> + bins_bag(Bin, From, To, L, Ts, R, Type, Size, 1, + Sz-ObjSz-4, ObjSz-4, Size-Sz, KO). + +bins_set(Bin, From, To, L, Ts, R, Type, Size, NoObjs, _ObjSz0, ?OHDSZ, KO) -> + slot_end(KO, From, To, L, [Bin | Ts], R, Type, Size, NoObjs); +bins_set(Bin, From, To, L, Ts, R, Type, Size, NoObjs, ObjSz0, ObjsSz, KO) -> + ObjSz = ObjSz0 - 4, + <<_:ObjSz/binary, NObjSz:32, T/binary>> = Bin, + bins_set(T, From, To, L, [Bin | Ts], R, Type, Size, NoObjs + 1, + NObjSz, ObjsSz-NObjSz, KO). + +bins_bag(Bin, From, To, L, Ts, R, Type, Size, NoObjs, Sz, ObjSz, ObjsSz, KO) + when Sz > 0 -> + <<_:ObjSz/binary, NObjSz:32, T/binary>> = Bin, + bins_bag(T, From, To, L, [Bin | Ts], R, Type, Size, NoObjs + 1, + Sz-NObjSz, NObjSz-4, ObjsSz, KO); +bins_bag(Bin, From, To, L, Ts, R, Type, Size, NoObjs, _Z, _ObjSz, ?OHDSZ, KO) -> + slot_end(KO, From, To, L, [Bin | Ts], R, Type, Size, NoObjs); +bins_bag(Bin, From, To, L, Ts, R, Type, Size, NoObjs, _Z, ObjSz, ObjsSz, KO) -> + <<_:ObjSz/binary, Sz:32, NObjSz:32, T/binary>> = Bin, + bins_bag(T, From, To, L, [Bin | Ts], R, Type, Size, NoObjs + 1, + Sz-NObjSz-4, NObjSz-4, ObjsSz-Sz, KO). + +slot_end(KO, From, To, L, Ts, R, Type, Size, NoObjs) -> + Skip = ?POW(dets_utils:log2(Size)) - 12, % expensive... + if + R >= 0 -> + scan_skip(KO, From, To, L, Ts, R+Size, Type, Skip); + true -> + %% Should check this at the end of every key. + case R + NoObjs of + R1 when R1 >= -1 -> + From1 = From + Skip, + Bin1 = case KO of + <<_:Skip/binary, B/binary>> -> B; + _ -> <<>> + end, + {stop, Bin1, From1, To, L, Ts}; + R1 -> + scan_skip(KO, From, To, L, Ts, R1, Type, Skip) + end + end. + +%%%%%%%%%%%%%%%%% DEBUG functions %%%%%%%%%%%%%%%% + +file_info(FH) -> + #fileheader{closed_properly = CP, keypos = Kp, + m = M, next = Next, n = N, version = Version, + type = Type, no_objects = NoObjects, no_keys = NoKeys} + = 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},{no_keys,NoKeys}, + {type,Type},{version,Version}]} + end. + +v_segments(#head{}=H) -> + v_parts(H, 0, 0). + +v_parts(_H, ?SEGARRSZ, _SegNo) -> + done; +v_parts(H, PartNo, SegNo) -> + Fd = H#head.fptr, + PartPos = dets_utils:read_4(Fd, ?SEGARRADDR(PartNo)), + if + PartPos =:= 0 -> + done; + true -> + PartBin = dets_utils:pread_n(Fd, PartPos, ?SEGPARTSZ*4), + v_segments(H, PartBin, PartNo+1, SegNo) + end. + +v_segments(H, <<>>, PartNo, SegNo) -> + v_parts(H, PartNo, SegNo); +v_segments(_H, <<0:32,_/binary>>, _PartNo, _SegNo) -> + done; +v_segments(H, <<Seg:32,T/binary>>, PartNo, SegNo) -> + io:format("<~w>SEGMENT ~w~n", [Seg, SegNo]), + v_segment(H, SegNo, Seg, 0), + v_segments(H, T, PartNo, SegNo+1). + +v_segment(_H, _, _SegPos, ?SEGSZP) -> + done; +v_segment(H, SegNo, SegPos, SegSlot) -> + Slot = SegSlot + (SegNo * ?SEGSZP), + BucketP = SegPos + (4 * ?SZOBJP * SegSlot), + case catch read_bucket(H, BucketP, H#head.type) of + {'EXIT', Reason} -> + dets_utils:vformat("** dets: Corrupt or truncated dets file~n", + []), + io:format("~nERROR ~p~n", [Reason]); + [] -> %% don't print empty buckets + true; + {Size, CollP, Objects} -> + io:format(" <~w>~w: <~w:~p>~w~n", + [BucketP, Slot, CollP, Size, Objects]) + end, + v_segment(H, SegNo, SegPos, SegSlot+1). + +%% -> [] | {Pointer, [object()]} | throw(EXIT) +read_bucket(Head, Position, Type) -> + MaxSize = maxobjsize(Head), + case dets_utils:ipread(Head, Position, MaxSize) of + {ok, {Size, Pointer, <<Size:32, _Status:32, KeysObjs/binary>>}} -> + Objs = bin2objs(KeysObjs, Type, []), + {Size, Pointer, lists:reverse(Objs)}; + [] -> + [] + end. + +-define(SEQSTART, -(1 bsl 26)). + +%% -> [{Key,SizeOfWholeKey,WholeKeyBin,FirstObject,OtherObjects}] |throw(EXIT) +%% FirstObject = {Term, Seq, Binary} +%% Seq < 0 (and ascending). +per_key(Head, <<BinSize:32, ?ACTIVE:32, Bin/binary>> = B) -> + true = (byte_size(B) =:= BinSize), + if + Head#head.type =:= set -> + per_set_key(Bin, Head#head.keypos, []); + true -> + per_bag_key(Bin, Head#head.keypos, []) + end. + +per_set_key(<<Size:32, T/binary>> = B, KeyPos, L) -> + <<KeyBin:Size/binary, R/binary>> = B, + Term = binary_to_term(T), + Key = element(KeyPos, Term), + Item = {Term, ?SEQSTART, KeyBin}, + per_set_key(R, KeyPos, [{Key,Size,KeyBin,Item,[]} | L]); +per_set_key(<<>>, KeyPos, L) when is_integer(KeyPos) -> + lists:reverse(L). + +per_bag_key(<<Size:32, ObjSz:32, T/binary>> = B, KeyPos, L) -> + <<KeyBin:Size/binary, R/binary>> = B, + ObjSz1 = ObjSz - 4, + Size1 = Size - ObjSz - 4, + <<_:ObjSz1/binary, KeyObjs:Size1/binary, _/binary>> = T, + <<_Size:32, Bin:ObjSz/binary, _/binary>> = B, + Term = binary_to_term(T), + Key = element(KeyPos, Term), + Item = {Term, ?SEQSTART, Bin}, + per_bag_key(R, KeyPos, [{Key,Size,KeyBin,Item,KeyObjs} | L]); +per_bag_key(<<>>, KeyPos, L) when is_integer(KeyPos) -> + lists:reverse(L). + + +binobjs2terms(<<ObjSz:32, T/binary>> = B) -> + binobjs2terms(B, T, ObjSz, byte_size(B)-ObjSz, ?SEQSTART+1, []); +binobjs2terms([] = B) -> + B; +binobjs2terms(<<>>) -> + []. + +binobjs2terms(Bin, Obj, _ObjSz, _Size=0, N, L) -> + lists:reverse(L, [{binary_to_term(Obj), N, Bin}]); +binobjs2terms(Bin, Bin1, ObjSz, Size, N, L) -> + <<B:ObjSz/binary, T/binary>> = Bin, + <<NObjSz:32, T1/binary>> = T, + Item = {binary_to_term(Bin1), N, B}, + binobjs2terms(T, T1, NObjSz, Size-NObjSz, N+1, [Item | L]). + + +%% Appends objects in reversed order. +bin2objs(KeysObjs, set, Ts) -> + <<ObjSz:32, T/binary>> = KeysObjs, + bin2objs(T, ObjSz-4, byte_size(KeysObjs)-ObjSz, Ts); +bin2objs(KeysObjs, _Type, Ts) -> + bin2objs2(KeysObjs, Ts). + +bin2objs2(<<Size:32, ObjSz:32, T/binary>>, Ts) -> + bin2objs(T, ObjSz-4, Size-ObjSz-4, Ts); +bin2objs2(<<>>, Ts) -> + Ts. + +bin2objs(Bin, ObjSz, _Size=0, Ts) -> + <<_:ObjSz/binary, T/binary>> = Bin, + bin2objs2(T, [binary_to_term(Bin) | Ts]); +bin2objs(Bin, ObjSz, Size, Ts) -> + <<_:ObjSz/binary, NObjSz:32, T/binary>> = Bin, + bin2objs(T, NObjSz-4, Size-NObjSz, [binary_to_term(Bin) | Ts]). + + +bin2keybins(KeysObjs, Head) when Head#head.type =:= set -> + <<ObjSz:32, T/binary>> = KeysObjs, + bin2keybins(T, Head#head.keypos, ObjSz-4, byte_size(KeysObjs)-ObjSz,[]); +bin2keybins(KeysObjs, Head) -> + bin2keybins2(KeysObjs, Head#head.keypos, []). + +bin2keybins2(<<Size:32, ObjSz:32, T/binary>>, Kp, L) -> + bin2keybins(T, Kp, ObjSz-4, Size-ObjSz-4, L); +bin2keybins2(<<>>, Kp, L) when is_integer(Kp) -> + lists:reverse(L). + +bin2keybins(Bin, Kp, ObjSz, _Size=0, L) -> + <<Obj:ObjSz/binary, T/binary>> = Bin, + Term = binary_to_term(Obj), + bin2keybins2(T, Kp, [{element(Kp, Term),Obj} | L]); +bin2keybins(Bin, Kp, ObjSz, Size, L) -> + <<Obj:ObjSz/binary, NObjSz:32, T/binary>> = Bin, + Term = binary_to_term(Obj), + bin2keybins(T, Kp, NObjSz-4, Size-NObjSz, [{element(Kp,Term),Obj} | L]). |