bsc-projects-14.html
changeset 314 906895d3a415
parent 313 2a98e65de47a
child 315 4c8ecc515721
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313:2a98e65de47a 314:906895d3a415
    74   mounting a nice <A HREF="http://en.wikipedia.org/wiki/Denial-of-service_attack">DoS attack</A> against 
    74   mounting a nice <A HREF="http://en.wikipedia.org/wiki/Denial-of-service_attack">DoS attack</A> against 
    75   your program if it contains such an &ldquo;evil&rdquo; regular expression. Actually 
    75   your program if it contains such an &ldquo;evil&rdquo; regular expression. Actually 
    76   <A HREF="http://www.scala-lang.org/">Scala</A> (and also Java) are almost immune from such
    76   <A HREF="http://www.scala-lang.org/">Scala</A> (and also Java) are almost immune from such
    77   attacks as they can deal with strings of up to 4,300 <code>a</code>s in less than a second. But if you scale
    77   attacks as they can deal with strings of up to 4,300 <code>a</code>s in less than a second. But if you scale
    78   the regular expression and string further to, say, 4,600 <code>a</code>s, then you get a <code>StackOverflowError</code> 
    78   the regular expression and string further to, say, 4,600 <code>a</code>s, then you get a <code>StackOverflowError</code> 
    79   potentially crashing your program. Moreover (beside the problem of being painfully slow) according to this
    79   potentially crashing your program. Moreover (beside the "minor" problem of being painfully slow) according to this
    80   <A HREF="http://www.haskell.org/haskellwiki/Regex_Posix">report</A>
    80   <A HREF="http://www.haskell.org/haskellwiki/Regex_Posix">report</A>
    81   nearly all POSIX regular expression matchers are actually buggy.
    81   nearly all POSIX regular expression matchers are actually buggy.
    82   </p>
    82   </p>
    83 
    83 
    84   <p>
    84   <p>
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