samples: net: dns_resolve: Improve DHCPv4 handling
There is some ambiguity with the DHCPv4 handling in the dns_resolve
sample. On one hand, the sample uses net_config library, which does
initiate the DHCPv4 on the interface (if enabled) and may block the
initialization until the address is assigned (in case there is no other
statically assigned IPv4 addresses.) On the other hand, the sample
registers for NET_EVENT_IPV4_ADDR_ADD in case DHCPv4 is in use, delaying
the DNS queries until address is assigned.
In case net_config delayed the initialization however, this will not
work, as the event handler will be registered only after DHCPv4 address
is assigned, so the callback will not get executed.
Fix this, by checking if DHCPv4 assigned address already exists on an
interface - if so, schedule DNS queries immediately. Otherwise (for
example in case when net_config was not configured to wait for address)
register an event callback, and schedule queries from there.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
1 file changed
