[issues/217] mlm_client_set_consumer broke the stream when pattern is *

[geraldguillaume]

Problem : zeromq#217
if pattern "*" is used, the related stream will be broken and mlm broker will start overcosumming 100% CPU forever

solution : if pattern is * mlm_set_consumer reject it

Note : as mlm_client_engine.inc is auto generated by gsl (https://github.com/zeromq/zproto/blob/master/src/zproto_client_c.gsl), it's quite really complex to handle this issue in a clean way. This is why we took a different approach, so this patch is not pushed on upstream.

Signed-off-by: Gerald Guillaume [email protected]

[boricj]

I would fail the call to mlm_client_set_consumer() instead. * is not a valid regex pattern, we should not hide a latent bug that'll explode whenever upstream will be properly fixed.

[geraldguillaume]

@boricj, the issue is that 'zrex_valid()' is wrong and returns true when checking "*" (as it was mentionned in zeromq#217).
So we can't trust zrex_valid() to validate the reggex.
As this issue is not yet fixed in upstream, I did this workaround.

[geraldguillaume]

would you prefer something like if (streq(pattern,"*")) return -1;

[boricj]

Yes. We should reject invalid regexes, not silently fix them up.