* perf: use scrape to know when a swarm is all-seeds
For private torrents, the tracker is the sole source of peers. So when a
private torrent's tracker responds that there are 0 leechers, we can use
that information to mark the entire swarm as seeders and to not initiate
connections to those peers if we are seeding. This can help seedboxes to
more efficiently pick which swarms to prioritize.
This strategy is not used on public torrents, since new seeder-to-seeder
connections can be useful there for pex.
This PR changes tr_peerMgrAddPex() to (1) remove tr_atom.seedProbability
field (which was not as robust as intended) and (2) add batches of peers
instead of a single peer.
* fix: only use all-seeds check for private torrents
This way all the qualifiers (`const`, `volatile`, `mutable`) are grouped
together, e.g. `T const* const x` vs. `const T* const x`. Also helps reading
types right-to-left, e.g. "constant pointer to constant T" vs. "constant
pointer to T which is constant".
There're places where manual intervention is still required as uncrustify
is not ideal (unfortunately), but at least one may rely on it to do the
right thing most of the time (e.g. when sending in a patch).
The style itself is quite different from what we had before but making it
uniform across all the codebase is the key. I also hope that it'll make the
code more readable (YMMV) and less sensitive to further changes.
1. add the option the code to be used under GPLv2 or GPLv3; previously only GPLv2 was allowed
2. add the "proxy option" as described in GPLv3 so we can add future licenses without having to bulk-edit everything again :)
3. remove the awkward "exception for MIT code in Mac client" clause; it was unnecessary and confusing.
This is a little overlapping since the utp code can be closed more-or-less immediately, but the udp manager needs to stay open in order to process the udp tracker connection requests before sending out event=stopped. Moreover DNS resolver can be shut down after the UDP tracker is shutdown.
Remove redundant code by using tr_peerMgrCompactToPex() and tr_peerMgrCompact6ToPex() to parse compact ipv4 and ipv6 peer lists. Simplify the old-style benc peer list parsing and fix a bug that returned too few bytes in the old-style peer array.
The Berne Convention says that the copyright year is moot, so instead of adding another year to each file as in previous years, I've removed the year altogether from the source code comments in libtransmission, gtk, qt, utils, daemon, and cli.
Juliusz's copyright notice in tr-dht and Johannes' copyright notice in tr-lpd have been left alone; it didn't seem appropriate to modify them.
Charles Kerr