This reverts (in sprit) commit f5cdf9515a,
"udev-rules: ignore non-system user/group in OWNER=/GROUP=".
The original change was done to clean up a situation where we added a
new group, but the group could already have been used for some other
purposes, and now the some unexpected entity would own the device.
Unfortunately, this check doesn't really address the issue, since the
existing account might as well be a system account, which might be
equally bad. In addition, this change is a big compatiblity break,
causing existing rules to stop working. Since quite a lot of systems
have local configuration to assign devices to users for various
purposes, this is very noticable to users. In a way, the original change
to add a new group was the compat break, and follow-up patch to cahnge
the rule parsing evolved a small compat break into a much bigger one.
There is merit to the change though, since device nodes shouldn't be
owned by users and groups and different mechanisms should be used
instead. To avoid breaking users systems, and since the original goal
cannot be achieved by this patch, let's downgrade this to a warning
to guide users towards different solutions.
We cannot just use %m, because strerror returns a confusing error message
for ESRCH or ENOEXEC. udev code was doing a good job, but the error handling
was very verbose. Let's encapsulate the customized error messages in a
helper.
No functional change, except that the error messages have a slightly different
form now. The old messages were a bit better, but we don't have as much
flexibility in the new scheme. "Failed to resolve user 'foo': Unknown user"
should be good enough.
This also makes shebang always use env command, and drops unnecessary
'bash -c' or 'sh -c' when a signle command is invoked in the shell,
like sleep or echo.
Otherwise, the result may point to outside of the root directory.
This also sets CONF_FILES_REGULAR and CONF_FILES_FILTER_MASKED, as the
callers will call fopen() or friends for the result, thus the enumerated
results must be non-empty regular files.
Zbigniew Jędrzejewski-Szmek
Yu Watanabe
Zbigniew Jędrzejewski-Szmek