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Alexander Gladysh kirjoitti 25.2.2009 kello 1:59:

On Wed, Feb 25, 2009 at 2:39 AM, Alex Davies <> wrote:
I did a quick, nonreliable test, and it took about 14 times longer with a C hook. Also, another problem I thought of: what if the script makes an IO
call?It'll still block...

It is a problem - your whole C library needs to either have a guaranteed
worse case time (even Lua's standard library doesn't offer this,
string/io/table libraries can take a long time performing their various
functions) or check the debug hooks themselves.

Yes, indeed.

("xyzzy"):rep(1e7):gsub("(z+)", "Z")

This one takes 4 seconds on my box, and has just 9 instructions.

While one can take away IO from untrusted code, string library is
usually a requirement...


Quite smart to think of this kind of issues; I've never realized them.

The only solution I'm aware of that currently offers cancellation of Lua states from the outside is Lanes. It will _really_ kill runaway cases, from the OS threading level, and then close their Lua states.