diff options
Diffstat (limited to 'lib/stdlib/src/dets.hrl')
| -rw-r--r-- | lib/stdlib/src/dets.hrl | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/lib/stdlib/src/dets.hrl b/lib/stdlib/src/dets.hrl new file mode 100644 index 0000000000..6e59770753 --- /dev/null +++ b/lib/stdlib/src/dets.hrl @@ -0,0 +1,126 @@ +%% +%% %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% +%% + +-define(DEFAULT_MIN_NO_SLOTS, 256). +-define(DEFAULT_MAX_NO_SLOTS, 2*1024*1024). +-define(DEFAULT_AUTOSAVE, 3). % minutes +-define(DEFAULT_CACHE, {3000, 14000}). % {delay,size} in {milliseconds,bytes} + +%% Type. +-define(SET, 1). +-define(BAG, 2). +-define(DUPLICATE_BAG, 3). + +-define(MAGIC, 16#0abcdef). % dets cookie, won't ever change. +%% Status values. +-define(FREE, 16#3abcdef). +-define(ACTIVE, 16#12345678). + +-define(FILE_FORMAT_VERSION_POS, 16). + +-define(CHUNK_SIZE, 8192). + +-define(SERVER_NAME, dets). + +-define(POW(X), (1 bsl (X))). + +%% REM2(A,B) = A rem B, if B is a power of 2. +-define(REM2(A, B), ((A) band ((B)-1))). + +-define(DETS_CALL(Pid, Req), {'$dets_call', Pid, Req}). + +%% Record holding the file header and more. +-record(head, { + m, % size + m2, % m * 2 + next, % next position for growth (segm mgmt only) + fptr, % the file descriptor + no_objects, % number of objects in table, + no_keys, % number of keys (version 9 only) + maxobjsize, % 2-log of the size of the biggest object + % collection (version 9 only) + n, % split indicator + type, % set | bag | duplicate_bag + keypos, % default is 1 as for ets + freelists, % tuple of free lists of buddies + % if fixed =/= false, then a pair of freelists + freelists_p, % cached FreelistsPointer + no_collections, % [{LogSize,NoCollections}] | undefined; number of + % object collections per size (version 9(b)) + auto_save, % Integer | infinity + update_mode, % saved | dirty | new_dirty | {error, Reason} + fixed = false, % false | {now_time(), [{pid(),Counter}]} + % time of first fix, and number of fixes per process + hash_bif, % hash bif used for this file (phash2, phash, hash) + has_md5, % whether the header has an MD5 sum (version 9(c)) + min_no_slots, % minimum number of slots (default or integer) + max_no_slots, % maximum number of slots (default or integer) + cache, % cache(). Write cache. + + filename, % name of the file being used + access = read_write, % read | read_write + ram_file = false, % true | false + name, % the name of the table + + parent, % The supervisor of Dets processes. + server, % The creator of Dets processes. + + %% Depending on the file format: + version, + mod, + bump, + base + + }). + +%% Info extracted from the file header. +-record(fileheader, { + freelist, + cookie, + closed_properly, + type, + version, + m, + next, + keypos, + no_objects, + no_keys, + min_no_slots, + max_no_slots, + no_colls, + hash_method, + read_md5, + has_md5, + md5, + trailer, + eof, + n, + mod + }). + +%% Write Cache. +-record(cache, { + cache, % [{Key,{Seq,Item}}], write cache, last item first + csize, % current size of the cached items + inserts, % upper limit on number of inserted keys + wrtime, % last write or update time + tsize, % threshold size of cache, in bytes + delay % max time items are kept in RAM only, in milliseconds + }). + |