Finishes the transition to make remote methods throw exceptions, rather
than silently hide them.
A bit on the fence about this one, because when renameExport fails,
it falls back to deleting instead, and so does the user care why it failed?
However, it did let me clean up several places in the code.
This commit was sponsored by Ethan Aubin.
When storing content on remote fails, always display a reason why.
Since the Storer used by special remotes already did, this mostly affects
git remotes, but not entirely. For example, if git-lfs failed to connect to
the endpoint, it used to silently return False.
This relicates git's behavior. It adds a few stat calls for the command
line parameters, so there is some minor slowdown, but even with thousands
of parameters it will not be very noticable, and git does the same statting
in similar circumstances.
Note that this does not prevent eg "git annex add symlink"; the symlink
will be added to git as usual. And "git annex find symlink" will silently
list nothing as well. It's only "symlink/foo" or "subdir/symlink/foo" that
triggers the warning.
Finishing work begun in 6952060665
Also, truncate filenames provided by other remotes if they're too long,
when --preserve-filename is not used. That seems to have been omitted
before by accident.
* addurl --preserve-filename: New option, uses server-provided filename
without any sanitization, but with some security checking.
Not yet implemented for remotes other than the web.
* addurl, importfeed: Avoid adding filenames with leading '.', instead
it will be replaced with '_'.
This might be considered a security fix, but a CVE seems unwattanted.
It was possible for addurl to create a dotfile, which could change
behavior of some program. It was also possible for a web server to say
the file name was ".git" or "foo/.git". That would not overrwrite the
.git directory, but would cause addurl to fail; of course git won't
add "foo/.git".
sanitizeFilePath is too opinionated to remain in Utility, so moved it.
The changes to mkSafeFilePath are because it used sanitizeFilePath.
In particular:
isDrive will never succeed, because "c:" gets munged to "c_"
".." gets sanitized now
".git" gets sanitized now
It will never be null, because sanitizeFilePath keeps the length
the same, and splitDirectories never returns a null path.
Also, on the off chance a web server suggests a filename of "",
ignore that, rather than trying to save to such a filename, which would
fail in some way.
