Libutp will sometimes call our callbacks after we called UTP_Close,
notably to notify us of the UTP_STATE_DESTROYING state change, but
also, for some reason, to ask us about our read buffer. The simplest
way to avoid issues with that is to switch to a second set of callbacks.
This adds code to participate in the UTP protocol, but without doing anything
useful yet -- we just shut down immediately any incoming connexion request.
This commit, started by a patch from athy, implements a rarest first policy when deciding which pieces to request from peers. It keeps a count of how many peers have each piece, and updates the count when getting bitfields, have, have all, and have none messages, as well as decrementing the counts when peers disconnect.
This running total is generated only for downloading torrents. Seeds don't have this overhead.
This patch adds two new flags to the callback function -- did_connect and did_timeout -- that are calculated inside of web.c using information from libcurl. This allows the announcer to detect timeouts more accurately and also to distinguish between unresponsive peers (which get the preexisting "Tracker did not respond" error message) and unconnectable peers (which get a new error message, "Could not connect to tracker").
We now try to contact the bootstrap nodes up to six times.
A better solution might be to reattempt bootstrap every half hour
or so. This might be beneficial to people whose connectivity
changes while Transmission is running.
update-version-h.sh tries to use {{{svnversion}}} when possible. But when it's not, it looks through the "$Id:" lines in the source file comments and uses the largest version number it finds. The new files tr-dht.[ch] didn't have the line of its $Id: comment formatted in the way update-version-h.sh expected. tr-dht.[ch]'s $Id: line has been homogenized to be like everyone else's...
remove() doesn't have the same behavior on Windows. On that platform, we should use MoveFileEx( oldpath, newpath, MOVEFILE_REPLACE_EXISTING )." Thanks to rb07 for testing & confirming the fix.
When libtransmission gets a "remove torrent" request from RPC, it tries to delegate the work. This is because the GTK+ and Mac clients don't want torrents disappearing in a different thread and causing possible thread issues. So the GTK+ and Mac clients get notification about this via libtransmission's RPC callback and remove the torrents themselves. Unfortunately, that notification doesn't include information about whether or not to delete local data.
This commit adds that information to the RPC callback so that the Mac and GTK+ clients will know whether or not to trash the local files when a third-party RPC client requests that at torrent and its files be deleted.
The 'bad tracker' penalty was introduced in 2009 after a top tier trackers went down. Announces to it would hang, tying up an announce slot in libcurl for minutes at a time. If a user had enough torrents from that tracker, it could bottleneck all announce slots. The workaround was to deprioritize failing trackers so that they wouldn't obstruct other trackers.
Its implementation could be better, however. There are two parts:
1. Deciding how frequently to retry unresponsive trackers
2. Once an unresponsive tracker announce was ready to go, it would be bumped down the queue if other announces were ready too.
Part 2 probably contributes to #3931. If there are enough torrents loaded, there will always be good tracker announces that get pushed ahead of a bad one in the queue. Modifying 2's heuristics would be one option, but it seems simpler to remove it altogether now that getRetryInterval() grades more hashly for consecutive failures. Altering the retry interval also gives better visual feedback to users than Part 2 did.
This commit removes "Part 2" as described above.
When saving a tr_benc object to disk at $dst, bencode.c saves it to a tmp file in the same directory as $dst, unlinks $dst if it exists, and then renames $tmp as $dst. This commit removes the middle step, which is unnecessary because rename() has guarantees about atomically overwriting $dst.
r11813 fixed the timestamp issue by fsync()ing files before close()ing them in tr_close_file(). This causes a little overhead as even read-only files cause a sync as their atimes are modified. Instead, we should call fsync() further back in the call chain in tr_fdFileClose() so that we can know to only sync torrent files that were opened with write access.
fsync() doesn't exist on Windows. bencode had a private function, tr_fsync(), that is a portability wrapper around fsync() on *nix and _commit() on win32. Make this function package-visible, rather than private, so fdlimit.c can use it too.
As pointed out by longinus00 and ijuxda, storing per-piece timestamps in the .resume file can involve a lot of overhead. This commit reduces the overhead by adding a couple of optimizations: (1) in cases where *all* or *none* of the files' pieces were checked after the file's mtime, we can safely fold all the pieces' mtimes into a single per-file mtime. (2) since unix time takes up a lot of space when rendered as a benc integer, find a common per-file "baseline" number, then store the pieces' timestamps as offsets from that number. Also add documentation explaining this new format, and also better explaining the pre-2.20 progress format.
Jordan Lee