1. simplifies and regularizies creation of listen sockets based on the listen
interfaces setting.
2. simplifies and improves the behavior of UDP sockets, which are now explicitly
opened per listen interface
3. transitions udp tracker, DHT and uTP socket manager over to using the new
udp sockets
4. greatly simplified udp_socket to only wrap a single underlying socket (as
opposed to one IPv4 and IPv6 socket)
5. improved behavior of bind-to-device
6. introduce an array_view type to make udp packet passing code simpler
7. simplify and make setting of DF flag more robust
8. simplify and regularize port mapping of listen sockets
It was too easy to forget to update the ret and size parameters
when the size of desec changed. With this change we now automatically
get the size of desc and enforce that ret has the same size.
It would be nice if we could use bdecode_node ret[static Size] from C99
but that is not widely supported.
If less than three nodes are found to put an item to then traversal_algorithm::start
will add router nodes. This leads to a crash in put_data::invoke when it tries to
read a token from uninitialized memory in a null_observer.
If an observer is abandoned due to there being more than 100 results in a
traversal then the traversal may complete while the observer is still
outstanding. When the observer times out or is aborted it calls
traversal_algorithm::failed() which asserts because m_invoke_count has been
cleared to zero by traversal_algorithm::done().
To fix this add a check when abandoning observers to see if they have an
outstanding query. If they do then flag them as done to prevent them from
calling back into the traversal and decrement the invoke count.
Fixes#271
A traversal can be done while there are still outstanding queries (i.e.
m_invoke_count is non-zero) if K good responses have already been received and
none of the outstanding queries are closer than the nodes which have responded.
When this happens and the outstanding queries eventually complete or timeout
they call traversal_algorithm::failed() or traversal_algorithm::finished() as
usual which will cause traversal_algorithm::done() to be called yet again.
The fix is to always set the done flag on all queried observers in
traversal_algorithm::done() so that the observers will refrain from calling
back into the traversal.
This also makes traversal_algorithm::abort() redundant since this was the only
thing it did before it called into done().