box.com already had a special case, since its renaming was known buggy.
In its case, renaming to the temp file succeeds, but then renaming the temp
file to final destination fails.
Then this 4shared server has buggy handling of renames across directories.
While already worked around with for the temp files when storing exports
now being in the same directory as the final filename, that also affected
renameExport when the file moves between directories.
I'm not entirely clear what happens on the 4shared server when it fails
this way. It kind of looks like it may rename the file to destination and
then still fail.
To handle both, when rename fails, delete both the source and the
destination, and fall back to uploading the content again. In the box.com
case, the temp file is the source, and deleting it makes sure the temp file
gets cleaned up. In the 4shared case, the file may have been renamed to the
destination and so cleaning that up avoids any interference with the
re-upload to the destination.
unregisterurl: Fix a bug that caused an url to not be unregistered when it
is claimed by a special remote other than the web.
See commit f175d4cc90 for rationalle.
* rmurl: When youtube-dl was used for an url, it no longer needs to be
prefixed with "yt:" in order to be removed.
* rmurl: If an url is both used by the web and also claimed by another
special remote, fix a bug that caused the url to to not be removed.
The youtube-dl change is a consequence of how the bug fix is implemented.
But I also think it's the right thing to do. Consider that, before,
git-annex addurl $url followed by git-annex rmurl $url would not remove the
url in the case where youtube-dl was used. That was surprising behavior.
In the unlikely case where a special remote claims an url, and it's been
added using OtherDownloader, but it was also added already as a web url,
it seems better for rmurl to remove both than to arbitrarily remove only one.
And in the case the bug report was filed for, when an url was added as a
web url, but a special remote now claims it, that should not prevent rmurl
removing the web url.
Calling setUrlMissing lets other callers of it behave differently.
Probably the calls to it in eg, Remote.External and Remote.BitTorrent are
fine, since they don't mangle the url and just remove what was provided,
and the OtherDownloader form of a bittorrent url, respectively.
I suspect unregisterurl needs to have a similar change made to rmurl, for
similar reasons.
When autoenabling special remotes of type S3, weddav, or glacier, do not
take login credentials from environment variables, as the user may not be
expecting the autoenable to happen, and may have those set for other
purposes.
