Thought was that this would be faster than a map, since a vector can be
updated more efficiently. It turns out to not seem to matter; runtime and
memory usage are basically identical.
This guarantees that stopping an existing socket never fails.
This might be the route out of the mess of needing to worry about socket
lengths in general. However, it would need quite a lot of refactoring
to make every place in git-annex that runs ssh run it with a cwd that was
determined by the location of its connection caching socket. If this
wasn't already such a mess, I'd consider even the thought of that API a bad
idea..
The control socket path passed to ssh needs to be 17 characters shorter
than the maximum unix domain socket length, because ssh appends stuff to it
to make a temporary filename. Closes: #725512
Also, take the shorter of the relative and the absolute paths to the
socket. Typically the relative path will be a lot shorter (unless
deep inside a subdirectory of the repository), and so using it will
avoid flirting with the maximum safe socket lenghts in more situations,
and so lead to less breakage if all my attempts at fixing this are
still buggy.
Extends the index.lock handling to other git lock files. I surveyed
all lock files used by git, and found more than I expected. All are
handled the same in git; it leaves them open while doing the operation,
possibly writing the new file content to the lock file, and then closes
them when done.
The gc.pid file is excluded because it won't affect the normal operation
of the assistant, and waiting for a gc to finish on startup wouldn't be
good.
All threads except the webapp thread wait on the new startup sanity checker
thread to complete, so they won't try to do things with git that fail
due to stale lock files. The webapp thread mostly avoids doing that kind of
thing itself. A few configurators might fail on lock files, but only if the
user is explicitly trying to run them. The webapp needs to start
immediately when the user has opened it, even if there are stale lock
files.
Arranging for the threads to wait on the startup sanity checker was a bit
of a bear. Have to get all the NotificationHandles set up before the
startup sanity checker runs, or they won't see its signal. Perhaps
the NotificationBroadcaster is not the best interface to have used for
this. Oh well, it works.
This commit was sponsored by Michael Jakl
FAT has a lot of characters it does not allow in filenames, like ? and *
It's probably the worst offender, but other filesystems also have
limitiations.
In 2011, I made keyFile escape : to handle FAT, but missed the other
characters. It also turns out that when I did that, I was also living
dangerously; any existing keys that contained a : had their object
location change. Oops.
So, adding new characters to escape to keyFile is out. Well, it would be
possible to make keyFile behave differently on a per-filesystem basis, but
this would be a real nightmare to get right. Consider that a rsync special
remote uses keyFile to determine the filenames to use, and we don't know
the underlying filesystem on the rsync server..
Instead, I have gone for a solution that is backwards compatable and
simple. Its only downside is that already generated URL and WORM keys
might not be able to be stored on FAT or some other filesystem that
dislikes a character used in the key. (In this case, the user can just
migrate the problem keys to a checksumming backend. If this became a big
problem, fsck could be made to detect these and suggest a migration.)
Going forward, new keys that are created will escape all characters that
are likely to cause problems. And if some filesystem comes along that's
even worse than FAT (seems unlikely, but here it is 2013, and people are
still using FAT!), additional characters can be added to the set that are
escaped without difficulty.
(Also, made WORM limit the part of the filename that is embedded in the key,
to deal with filesystem filename length limits. This could have already
been a problem, but is more likely now, since the escaping of the filename
can make it longer.)
This commit was sponsored by Ian Downes
