Re: [Boost-users] regex problem in multithreading...

From: John Maddock (john_at_[hidden])
Date: 2006-07-28 05:06:01

yogendra karki wrote:
>> Hello all,
>> i am using boost regex to check the syntax of a URL. the regex is as
>> :-
>>
>> static const char *URLSYNTAXREGEX =
>> "^((file|https?|ftp)://)?(([-a-zA-Z0-9_]+[.]{1})+(([-a-zA-Z0-9]+))([:]{1}([0-9]+)){0,1})([?/][^[:space:]]*)?"
>>
>> the function for evaluation is:-
>>
>> bool URLHandler::EvaluateRegex(const char *regularexp,std::string
>>        url){ boost::smatch what;
>>        boost::regex exp(regularexp,boost::regex::extended);
>>        boost::regex_search(url,what,exp);
>>        std::string search=(std::string)what[0];
>>        if(search.length() == url.length())
>>        {
>>                return true;
>>        }
>>        else
>>        {
>>                return false;
>>         }
>> }
>>
>> when i am running this code with single thread it is running fine.
>> But when i am integrating this code with a multithreaded application
>> it is giving this error:-
>>
>> terminate called after throwing an instance of 'boost::regex_error'
>>  what():  Invalid content of repeat range
>> Aborted
>>
>> Can you please help me in this. Its very urgent for me.

Well plainly that shouldn't happen: as a first step I would get your 
debugger to break on thrown exceptions, then walk up the stack and verify 
that the regex being passed is actually valid.  If you suspect a regex bug 
then you will have to supply a test case so I can reproduce the issue here.

Regards, John Maddock.