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re: Fix non-termination for a certain regular expression

The following code never terminates:

fail() ->
     Str = "http:/www.flickr.com/slideShow/index.gne?group_id=&user_id=69845378@N0",
     EMail_regex = "[a-z0-9!#$%&'*+/=?^_`{|}~-]+"
       ++ "(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*"
       ++ "@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+"
       ++ "(?:[a-zA-Z]{2}|com|org|net|gov|mil"
       ++ "|biz|info|mobi|name|aero|jobs|museum)",
   io:format("about to run...~n"),
   Ret = re:run(Str, EMail_regex),
   io:format("Ret is ~p~n", [Ret]).

Fix it by having pcre_exec remember match_call_count between restarts.

Reported-by: Gordon Guthrie
Acked-by: Patrik Nyblom
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1 parent 09ca69e commit 78a48004ed9e488de702baa63763ce6e6b602a93 @msantos msantos committed with bjorng Apr 20, 2010
Showing with 0 additions and 1 deletion.
  1. +0 −1 erts/emulator/pcre/pcre_exec.c
@@ -5191,7 +5191,6 @@ for(;;)
EDEBUGF(("Loop limit break detected"));
return PCRE_ERROR_LOOP_LIMIT;
RESTART_INTERRUPTED:
- md->match_call_count = 0;
md->loop_limit = extra_data->loop_limit;
rc = match(NULL,NULL,NULL,0,md,0,NULL,0,0);
*extra_data->loop_counter_return =

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