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  • Committer: Package Import Robot
  • Author(s): Sergei Golovan
  • Date: 2011-12-15 19:20:10 UTC
  • mfrom: (1.1.18) (3.5.15 sid)
  • mto: (3.5.16 sid)
  • mto: This revision was merged to the branch mainline in revision 33.
  • Revision ID: package-import@ubuntu.com-20111215192010-jnxcfe3tbrpp0big
Tags: 1:15.b-dfsg-1
* New upstream release.
* Upload to experimental because this release breaks external drivers
  API along with ABI, so several applications are to be fixed.
* Removed SSL patch because the old SSL implementation is removed from
  the upstream distribution.
* Removed never used patch which added native code to erlang beam files.
* Removed the erlang-docbuilder binary package because the docbuilder
  application was dropped by upstream.
* Documented dropping ${erlang-docbuilder:Depends} substvar in
  erlang-depends(1) manpage.
* Made erlang-base and erlang-base-hipe provide virtual package
  erlang-abi-15.b (the number means the first erlang version, which
  provides current ABI).

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lib/dialyzer/test/r9c_SUITE_data/src/mnesia/mnesia_frag_old_hash.erl
 
1
%% ``The contents of this file are subject to the Erlang Public License,
 
2
%% Version 1.1, (the "License"); you may not use this file except in
 
3
%% compliance with the License. You should have received a copy of the
 
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%% Erlang Public License along with this software. If not, it can be
 
5
%% retrieved via the world wide web at http://www.erlang.org/.
 
6
%%
 
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%% Software distributed under the License is distributed on an "AS IS"
 
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%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 
9
%% the License for the specific language governing rights and limitations
 
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%% under the License.
 
11
%%
 
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%% The Initial Developer of the Original Code is Ericsson Utvecklings AB.
 
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%% Portions created by Ericsson are Copyright 1999, Ericsson Utvecklings
 
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%% AB. All Rights Reserved.''
 
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%%
 
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%%     $Id: mnesia_frag_old_hash.erl,v 1.1 2008/12/17 09:53:38 mikpe Exp $
 
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%%
 
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%%%----------------------------------------------------------------------
 
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%%% Purpose : Implements hashing functionality for fragmented tables
 
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%%%----------------------------------------------------------------------
 
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-module(mnesia_frag_old_hash).
 
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-behaviour(mnesia_frag_hash).
 
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%% Hashing callback functions
 
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-export([
 
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         init_state/2,
 
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         add_frag/1,
 
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         del_frag/1,
 
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         key_to_frag_number/2,
 
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         match_spec_to_frag_numbers/2
 
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        ]).
 
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-record(old_hash_state,
 
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        {n_fragments,
 
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         next_n_to_split,
 
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         n_doubles}).
 
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%% Old style. Kept for backwards compatibility.
 
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-record(frag_hash,
 
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        {foreign_key,
 
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         n_fragments,
 
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         next_n_to_split,
 
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         n_doubles}).
 
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
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init_state(_Tab, InitialState) when InitialState == undefined ->
 
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    #old_hash_state{n_fragments     = 1,
 
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                    next_n_to_split = 1,
 
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                    n_doubles       = 0};
 
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init_state(_Tab, FH) when record(FH, frag_hash) ->
 
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    %% Old style. Kept for backwards compatibility.
 
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    #old_hash_state{n_fragments     = FH#frag_hash.n_fragments,
 
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                    next_n_to_split = FH#frag_hash.next_n_to_split,
 
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                    n_doubles       = FH#frag_hash.n_doubles}.
 
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
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add_frag(State) when record(State, old_hash_state) ->
 
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    SplitN = State#old_hash_state.next_n_to_split,
 
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    P = SplitN + 1,
 
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    L = State#old_hash_state.n_doubles,
 
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    NewN = State#old_hash_state.n_fragments + 1,
 
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    State2 = case trunc(math:pow(2, L)) + 1 of
 
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                 P2 when P2 == P ->
 
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                     State#old_hash_state{n_fragments = NewN,
 
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                                          next_n_to_split = 1,
 
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                                          n_doubles = L + 1};
 
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                 _ ->
 
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                     State#old_hash_state{n_fragments = NewN,
 
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                                          next_n_to_split = P}
 
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             end,
 
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    {State2, [SplitN], [NewN]}.
 
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
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del_frag(State) when record(State, old_hash_state) ->
 
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    P = State#old_hash_state.next_n_to_split - 1,
 
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    L = State#old_hash_state.n_doubles,
 
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    N = State#old_hash_state.n_fragments,
 
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    if
 
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        P < 1 ->
 
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            L2 = L - 1,
 
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            MergeN = trunc(math:pow(2, L2)),
 
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            State2 = State#old_hash_state{n_fragments = N - 1,
 
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                                          next_n_to_split = MergeN,
 
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                                          n_doubles = L2},
 
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            {State2, [N], [MergeN]};
 
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        true ->
 
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            MergeN = P,
 
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            State2 = State#old_hash_state{n_fragments = N - 1,
 
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                                          next_n_to_split = MergeN},
 
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            {State2, [N], [MergeN]}
 
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        end.
 
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
98
 
 
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key_to_frag_number(State, Key) when record(State, old_hash_state) ->
 
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    L = State#old_hash_state.n_doubles,
 
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    A = erlang:hash(Key, trunc(math:pow(2, L))),
 
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    P = State#old_hash_state.next_n_to_split,
 
103
    if
 
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        A < P ->
 
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            erlang:hash(Key, trunc(math:pow(2, L + 1)));
 
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        true ->
 
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            A
 
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    end.
 
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
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match_spec_to_frag_numbers(State, MatchSpec) when record(State, old_hash_state) ->
 
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    case MatchSpec of
 
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        [{HeadPat, _, _}] when tuple(HeadPat), size(HeadPat) > 2 ->
 
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            KeyPat = element(2, HeadPat),
 
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            case has_var(KeyPat) of
 
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                false ->
 
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                    [key_to_frag_number(State, KeyPat)];
 
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                true ->
 
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                    lists:seq(1, State#old_hash_state.n_fragments)
 
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            end;
 
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        _ ->
 
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            lists:seq(1, State#old_hash_state.n_fragments)
 
124
    end.
 
125
 
 
126
has_var(Pat) ->
 
127
    mnesia:has_var(Pat).