Hi
In the poller function:
void
sfl_poller_set_sFlowCpInterval (SFLPoller * poller, u_int32_t sFlowCpInterval)
{
poller->sFlowCpInterval = sFlowCpInterval;
/* Set the countersCountdown to be a randomly selected value between 1 and
sFlowCpInterval. That way the counter polling would be desynchronised
(on a 200-port switch, polling all the counters in one second could be
harmful). */
poller->countersCountdown = 1 + (random () % sFlowCpInterval); <--- MAY NOT
DO WHAT YOU THINK IF sFlowCpInterval == 0!!
}
The subexpression "random () % sFlowCpInterval" results in undefined behaviour
according to the C and C++ standards, if sFlowCpInterval is zero.
Depending on what platform you compile this on, you get different results.
For example, on the i686, I got a floating point error at runtime.
On a PowerPC, the expression evaluated to 1 + random().
Zero is a valid value for sFlowCpInterval according to the sFlow specification
V5, so shouldn't poller->countersCountdown be set to zero in this case?
Regards
Andy
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