Fix a bug concerning bchunk(), match() and select()

If a Dets table was closed after calling bchunk/2, match/1,3,
match_object/1,3, or select/1,3 and then opened again, a subsequent
call using the returned continuation would normally return a reply.
This bug has fixed; now the call fails with reason 'badarg'.

2 files changed, 63 insertions, 37 deletions

diff --git a/lib/stdlib/src/dets.erl b/lib/stdlib/src/dets.erl
index 4584b8184f..cf68958a9f 100644
--- a/lib/stdlib/src/dets.erl
+++ b/lib/stdlib/src/dets.erl
@@ -147,6 +147,7 @@
 	 bin,         % small chunk not consumed, or 'eof' at end-of-file
 	 alloc,       % the part of the file not yet scanned, mostly a binary
 	 tab,
+         proc,        % the pid of the Dets process
          match_program % true | compiled_match_spec() | undefined
 	 }).
 
@@ -208,8 +209,6 @@ all() ->
 
 bchunk(Tab, start) ->
     badarg(treq(Tab, {bchunk_init, Tab}), [Tab, start]);
-bchunk(Tab, #dets_cont{bin = eof, tab = Tab}) ->
-    '$end_of_table';
 bchunk(Tab, #dets_cont{what = bchunk, tab = Tab} = State) ->
     badarg(treq(Tab, {bchunk, State}), [Tab, State]);
 bchunk(Tab, Term) ->
@@ -722,11 +721,14 @@ init_chunk_match(Tab, Pat, What, N) when is_integer(N), N >= 0;
                                          N =:= default ->
     case compile_match_spec(What, Pat) of
 	{Spec, MP} ->
-	    case req(dets_server:get_pid(Tab), {match, MP, Spec, N}) of
+            Proc = dets_server:get_pid(Tab),
+	    case req(Proc, {match, MP, Spec, N}) of
 		{done, L} ->
-		    {L, #dets_cont{tab = Tab, what = What, bin = eof}};
+		    {L, #dets_cont{tab = Tab, proc = Proc, what = What,
+                                   bin = eof}};
 		{cont, State} ->
-		    chunk_match(State#dets_cont{what = What, tab = Tab});
+		    chunk_match(State#dets_cont{what = What, tab = Tab,
+                                                proc = Proc});
 		Error ->
 		    Error
 	    end;
@@ -736,34 +738,28 @@ init_chunk_match(Tab, Pat, What, N) when is_integer(N), N >= 0;
 init_chunk_match(_Tab, _Pat, _What, _) ->
     badarg.
 
-chunk_match(State) ->
-    case catch dets_server:get_pid(State#dets_cont.tab) of
-	{'EXIT', _Reason} ->
-	    badarg;
-	_Proc when State#dets_cont.bin =:= eof ->
-	    '$end_of_table';
-	Proc ->
-	    case req(Proc, {match_init, State}) of
-		{cont, {Bins, NewState}} ->
-		    MP = NewState#dets_cont.match_program,
-		    case catch do_foldl_bins(Bins, MP) of
-			{'EXIT', _} ->
-                            case ets:is_compiled_ms(MP) of
-                                true ->
-                                    Bad = dets_utils:bad_object(chunk_match, 
-                                                                Bins),
-                                    req(Proc, {corrupt, Bad});
-                                false ->
-                                    badarg
-                            end;
-                        [] ->
-                            chunk_match(NewState);
-			Terms ->
-			    {Terms, NewState}
-		    end;
-		Error ->
-		    Error
-	    end
+chunk_match(#dets_cont{proc = Proc}=State) ->
+    case req(Proc, {match_init, State}) of
+        '$end_of_table'=Reply ->
+            Reply;
+        {cont, {Bins, NewState}} ->
+            MP = NewState#dets_cont.match_program,
+            case catch do_foldl_bins(Bins, MP) of
+                {'EXIT', _} ->
+                    case ets:is_compiled_ms(MP) of
+                        true ->
+                            Bad = dets_utils:bad_object(chunk_match, Bins),
+                            req(Proc, {corrupt, Bad});
+                        false ->
+                            badarg
+                    end;
+                [] ->
+                    chunk_match(NewState);
+                Terms ->
+                    {Terms, NewState}
+            end;
+        Error ->
+            Error
     end.
 
 do_foldl_bins(Bins, true) ->
@@ -1578,13 +1574,18 @@ do_bchunk_init(Head, Tab) ->
                     L = dets_utils:all_allocated(H2),
                     C0 = #dets_cont{no_objs = default, bin = <<>>, alloc = L},
 		    BinParms = term_to_binary(Parms),
-		    {H2, {C0#dets_cont{tab = Tab, what = bchunk}, [BinParms]}}
+		    {H2, {C0#dets_cont{tab = Tab, proc = self(),what = bchunk},
+                          [BinParms]}}
 	    end;
 	{NewHead, _} = HeadError when is_record(NewHead, head) ->
 	    HeadError
     end.
 
 %% -> {NewHead, {cont(), [binary()]}} | {NewHead, Error}
+do_bchunk(Head, #dets_cont{proc = Proc}) when Proc =/= self() ->
+    {Head, badarg};
+do_bchunk(Head, #dets_cont{bin = eof}) ->
+    {Head, '$end_of_table'};
 do_bchunk(Head, State) ->
     case dets_v9:read_bchunks(Head, State#dets_cont.alloc) of
 	{error, Reason} ->
@@ -1954,6 +1955,8 @@ flookup_keys(Head, Keys) ->
     end.
 
 %% -> {NewHead, Result}
+fmatch_init(Head, #dets_cont{bin = eof}) ->
+    {Head, '$end_of_table'};
 fmatch_init(Head, C) ->
     case scan(Head, C) of
 	{scan_error, Reason} ->
diff --git a/lib/stdlib/test/dets_SUITE.erl b/lib/stdlib/test/dets_SUITE.erl
index 760e610e00..3c938313b4 100644
--- a/lib/stdlib/test/dets_SUITE.erl
+++ b/lib/stdlib/test/dets_SUITE.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2010. 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
@@ -50,7 +50,7 @@
 	 otp_4208/1, otp_4989/1, many_clients/1, otp_4906/1, otp_5402/1,
          simultaneous_open/1, insert_new/1, repair_continuation/1,
          otp_5487/1, otp_6206/1, otp_6359/1, otp_4738/1, otp_7146/1,
-         otp_8070/1]).
+         otp_8070/1, otp_8903/1]).
 
 -export([dets_dirty_loop/0]).
 
@@ -108,7 +108,7 @@ all(suite) ->
 	      cache_duplicate_bags_v9, otp_4208, otp_4989, many_clients,
               otp_4906, otp_5402, simultaneous_open, insert_new, 
               repair_continuation, otp_5487, otp_6206, otp_6359, otp_4738,
-              otp_7146, otp_8070]} 
+              otp_7146, otp_8070, otp_8903]}
     end.
 
 not_run(suite) -> [];
@@ -3701,6 +3701,29 @@ otp_8070(Config) when is_list(Config) ->
     file:delete(File),
     ok.
 
+otp_8903(doc) ->
+    ["OTP-8903. bchunk/match/select bug."];
+otp_8903(suite) ->
+    [];
+otp_8903(Config) when is_list(Config) ->
+    Tab = otp_8903,
+    File = filename(Tab, Config),
+    ?line {ok,T} = dets:open_file(bug, [{file,File}]),
+    ?line ok = dets:insert(T, [{1,a},{2,b},{3,c}]),
+    ?line dets:safe_fixtable(T, true),
+    ?line {[_],C1} = dets:match_object(T, '_', 1),
+    ?line {BC1,_D} = dets:bchunk(T, start),
+    ?line ok = dets:close(T),
+    ?line {'EXIT', {badarg, _}} = (catch {foo,dets:match_object(C1)}),
+    ?line {'EXIT', {badarg, _}} = (catch {foo,dets:bchunk(T, BC1)}),
+    ?line {ok,T} = dets:open_file(bug, [{file,File}]),
+    ?line false = dets:info(T, safe_fixed),
+    ?line {'EXIT', {badarg, _}} = (catch {foo,dets:match_object(C1)}),
+    ?line {'EXIT', {badarg, _}} = (catch {foo,dets:bchunk(T, BC1)}),
+    ?line ok = dets:close(T),
+    file:delete(File),
+    ok.
+
 %%
 %% Parts common to several test cases
 %%