As another device may be created with the same device node while udevd
is processing the remove event of the previous owner of the device node.
This also adds comment why we skip watching device node on remove.
-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.
Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state
Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.
In some places, initialization is dropped if unnecessary.
Before removing symlinks that stores watch handles, this makes udev
worker check if the symlink is owned by the processing device.
Then, we can avoid TOCTOU and drop the try-and-wait loop.
This partially reverts 2d3af41f0e.
The variable is not useful outside of the loop (it'll always be null
after the loop is finished), so we can declare it inline in the loop.
This saves one variable declaration and reduces the chances that somebody
tries to use the variable outside of the loop.
For consistency, 'de' is used everywhere for the var name.
Previously, watch handle is saved in the udev databse. But in most cases,
the handle saved in the database is not updated. Especially, when udevd
is restarted, the inotify watch is restarted, but the database is not
updated.
Moreover, it is not necessary to save watch handle in the database, as
the handle is only take a effect during udevd is running, and the value
is meaningless when udevd is restarted.
So, this makes the opposite map from device ID to watch handle is saved
in /run/udev/watch as a symbolic link, and the handle not saved in the
database anymore.
Fixes#18525.
When manager_exit() or manager_free() is called, the global variable in
udev-watch.c is not set '-1'. Of course, that is safe, as the event source
for the inotify fd is unref()ed in manager_exit() and manager_free().
But let's not store fd globally.
E.g. udevadm test prints "Invalid inotify descriptor." which is
meaningless without any context. I think it should be OK to call udev_watch_end()
from a cleanup path without any warning (even at debug level).
My logs are full of:
systemd-udevd[6586]: seq 13515 queued, 'add' 'block'
systemd-udevd[6586]: seq 13516 queued, 'change' 'block'
systemd-udevd[6586]: seq 13517 queued, 'change' 'block'
systemd-udevd[6586]: seq 13518 queued, 'remove' 'bdi'
systemd-udevd[6586]: seq 13519 queued, 'remove' 'block'
systemd-udevd[9865]: seq 13514 processed
systemd-udevd[9865]: seq 13515 running
systemd-udevd[9865]: GROUP 6 /usr/lib/udev/rules.d/50-udev-default.rules:59
systemd-udevd[9865]: IMPORT builtin 'blkid' /usr/lib/udev/rules.d/60-persistent-storage.rules:95
systemd-udevd[9865]: IMPORT builtin 'blkid' fails: No such file or directory
systemd-udevd[9865]: loop4: Failed to add device '/dev/loop4' to watch: No such file or directory
(the last line is at error level).
If we are too slow to set up a watch and the device is already gone by the time
we try, this is not an error.
$ git grep -e 'This program is free software' -l |grep -v LICENSE | \
xargs perl -i -0pe 's/ \* This program.*?for more details.\s*\*\n( \* You should have.*licenses.>.\n)?//gms'
For some reason they were missed previously. All those files seem to
have proper SDPX tags.
Coverity now started warning about this ("Calling unlinkat without checking
return value (as is done elsewhere 12 out of 15 times).", and it is right:
most of the time we should at list print a log message so people can figure
out something is wrong when this happens.
v2:
- use warning level in journald too (this is unlikely to happen ever, so it
should be safe to something that is visible by default).
This patch removes includes that are not used. The removals were found with
include-what-you-use which checks if any of the symbols from a header is
in use.
If the format string contains %m, clearly errno must have a meaningful
value, so we might as well use log_*_errno to have ERRNO= logged.
Using:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\((".*%m.*")/log_\1_errno(errno, \2/'
Plus some whitespace, linewrap, and indent adjustments.