Attached is a patch against udev-008 to send out a D-BUS message when a
device node is added or removed.
Using D-BUS lingo, udev acquires the org.kernel.udev service and sends
out a NodeCreated or NodeDeleted signal on the
org.kernel.udev.NodeMonitor interface. Each signal carries two
parameters: the node in question and the corresponding sysfs path.
[Note: the D-BUS concepts of service, interface, object can be a bit
confusing at first glance]
An example program listening for these messages looks like this
#!/usr/bin/python
import dbus
import gtk
def udev_signal_received(dbus_iface, member, service, object_path, message):
[filename, sysfs_path] = message.get_args_list()
if member=='NodeCreated':
print 'Node %s created for %s'%(filename, sysfs_path)
elif member=='NodeDeleted':
print 'Node %s deleted for %s'%(filename, sysfs_path)
def main():
bus = dbus.Bus(dbus.Bus.TYPE_SYSTEM)
bus.add_signal_receiver(udev_signal_received,
'org.kernel.udev.NodeMonitor', # interface
'org.kernel.udev', # service
'/org/kernel/udev/NodeMonitor') # object
gtk.mainloop()
if __name__ == '__main__':
main()
and this is the output when hot-plugging some usb-storage.
[david@laptop udev-008]$ ~/node_monitor.py
Node /udev/sda created for /block/sda
Node /udev/sda1 created for /block/sda/sda1
Node /udev/sda1 deleted for /block/sda/sda1
Node /udev/sda deleted for /block/sda
The patch requires D-BUS 0.20 or later while the python example program
requires D-BUS from CVS as I only recently applied a patch against the
python bindings.
> > here is a experimental symlink creation patch - for discussion,
> > in which direction we should go.
> > It is possible now to define SYMLINK= after the NAME= in udev.rules.
> > The link is relative to the node, but the path is not optimized now
> > if the node and the link are in the same nested directory.
> > Only one link is supported, cause i need to sleep now :)
> >
> > 06-simple-symlink-creation.diff
> > simple symlink creation
> > reorganized udev-remove to have access to the symlink field
> > subdir creation/removal are functions now
> > udev-test.pl tests for link creation/removal
Here is a new version with relative link target path optimization
an better tests in udev-test.pl:
LABEL, BUS="scsi", vendor="IBM-ESXS", NAME="1/2/a/b/node", SYMLINK="1/2/c/d/symlink"
Dec 7 06:48:34 pim udev[13789]: create_node: symlink 'udev-root/1/2/c/d/symlink' to node '1/2/a/b/node' requested
Dec 7 06:48:34 pim udev[13789]: create_path: created 'udev-root/1/2/c'
Dec 7 06:48:34 pim udev[13789]: create_path: created 'udev-root/1/2/c/d'
Dec 7 06:48:34 pim udev[13789]: create_node: symlink(../../a/b/node, udev-root/1/2/c/d/symlink)
Here is an improved version of the patch that enables builds of the extras
progams for the targets all, clean, install, and uninstall, and passes
down the "prefix" for use by install and uninstall.
This patch enables building of the "extras" programs using the same build
environment as udev (i.e. build with udev's versions of klibc and
sysfsutils).
For example, build scsi_id and udev via:
make EXTRAS=extras/scsi_id
Build scsi_id and udev with klibc via:
make KLIBC=true EXTRAS=extras/scsi_id
* implement a reschedule flag in /var/run. Last thing the prog do before
exit is check if a call to multipath was done (but canceled by
/var/run/multipath.run check) during its execution. If so restart the
main loop.
* implement a blacklist of sysfs bdev to not bother with for now (hd,
md, dm, sr, scd, ram, raw). This avoid sending SG_IO to unappropiate
devices.
Compiles & survive "while true;do (./multipath -v &);done"
here is the next update which brings this multipath to the state i'm not
ashamed of it being in udev :)
* drop a libdevmapper copy in extras/multipath; maybe discussions w/
Sistina folks will bring a better solution in the future.
* drop a putchar usage in libdevmapper to compile cleanly with klibc
* drop another such usage of my own in main.c
* massage the Makefile to compile libdevmapper against klibc
* use "ld" to produce the binary rather than "gcc -static"
* stop being stupid w/ uneeded major, minor & dev in main.c:dm_mk_node()
* reverse to creating striped target for now because the multipath
target is more hairy than expected initialy
* push the version code to 009 to be in synch w/ udev
builds & run here.
binary size is 43ko, which is fairly gratifying after all the efforts
I've put to compiling it with klibc :)
I've never seen any project where the documentation is in sync with the
code at this early stage. Nice! So here is the patch to make it extra perfect :)
remove random indent to be consistent
style is "shell style"
s/wildcard/pattern/
mention negation char in character class
While I was adding pattern match to the LABEL method i hit a bug.
We modify a string returned from libsysfs, so with every iteration is is
truncated by one char:
Dec 4 02:27:16 pim udev[23307]: do_label: dev->bus='scsi' sysfs_device->bus='scsi'
Dec 4 02:27:16 pim udev[23307]: do_label: look for device attribute 'vendor'
Dec 4 02:27:16 pim udev[23307]: do_label: xxx 'IBM-ESXS '
Dec 4 02:27:16 pim udev[23307]: do_label: compare attribute 'vendor' value 'IBM-ESX' with '?IBM-ESXS'
Dec 4 02:27:16 pim udev[23307]: do_label: dev->bus='scsi' sysfs_device->bus='scsi'
Dec 4 02:27:16 pim udev[23307]: do_label: look for device attribute 'vendor'
Dec 4 02:27:16 pim udev[23307]: do_label: xxx 'IBM-ESX'
Dec 4 02:27:16 pim udev[23307]: do_label: compare attribute 'vendor' value 'IBM-ES' with 'IBM-ESXS?'
Dec 4 02:27:16 pim udev[23307]: do_label: dev->bus='scsi' sysfs_device->bus='scsi'
Dec 4 02:27:16 pim udev[23307]: do_label: look for device attribute 'vendor'
Dec 4 02:27:16 pim udev[23307]: do_label: xxx 'IBM-ES'
Dec 4 02:27:16 pim udev[23307]: do_label: compare attribute 'vendor' value 'IBM-E' with 'IBM-ES??'
Dec 4 02:27:16 pim udev[23307]: do_label: dev->bus='scsi' sysfs_device->bus='scsi'
Dec 4 02:27:16 pim udev[23307]: do_label: look for device attribute 'vendor'
Dec 4 02:27:16 pim udev[23307]: do_label: xxx 'IBM-E'
Dec 4 02:27:16 pim udev[23307]: do_label: compare attribute 'vendor' value 'IBM-' with 'IBM-ESXSS'
I changed the behavior to remove only the line feed.
03-bug-in-linefeed-removal.diff
remove only the line feed from string not every last char
As promised yesterday, here is a patch to implement a more advanced
pattern matching instead of the simple '*'.
We can remove the "tty"="tty" line from udev.rules now and
replace "tty*" by "tty[0-9]*" to catch only the vc's.
implement pattern matching in namedev
'*' - to match zero or more chars
'?' - to match exactly one char
'[]' - character classes with ranges '[0-9]'and negation [!A]
the older udev.config file is now called udev.rules.
This allows us to better control configuration values, and move away from
the environment variables.
This patch adds -nodefaultlibs to LDFLAGS when compiling udev against
klibc. This fixes the warning that I was getting when using $(LD)=gcc
in the versions after Makefile.klibc disappeared. The problem was that
it was still including a "-lc" in the call to the linker.
The quick patch I sent you yesterday fixes it in one location, but
there are other points in the library that calls sysfs_get_mnt_path. We
need to address all the areas in the library where paths are used. The
following patch is a band-aid until we can get a proper path management
in the library.
On Tuesday 25 November 2003 00:12, Chris Larson wrote:
> udev fails to compile here unless I'm doing a KLIBC build. The reason
> appears to be that the normal limits.h in the gcc inc dir doesn't pull
> in linux/limits.h, whereas the limits.h out in the klibc include dirs
> does. I'd think it'd be best to add a #include <linux/limits.h> to
> udev.h directly, since it uses PATH_MAX.
No, don't include kernel headers directly if you can avoid it.
The problem you are referring to seems to be with old tool chains,
I have the same symptom with my s390 gcc-2.95/glibc-2.1.3.
Including <sys/param.h> instead of <limits.h> seems to fix it.
here is a clean-up patch :
* removes sg_err.[ch] deps
* makes sure the core code play nice with klibc
* port the sysfs calls to dlist helpers
* links against udev's sysfs (need libsysfs.a & dlist.a)
* finally define DM_TARGET as "multipath" as Joe posted the code today
(not tested yet)
* push version forward (do you want it in sync with udev version?)
libdevmapper doesn't play well with klibc, so I wasn't able to produce a
static binary yet. Help needed here ... as I don't want to fall back to
merge libdevmapper code in the core.
It compiles here and doesn't segfault.
There seems to be a
mismatch in udev and in libsysfs as to what to expect if the mnt point
has a slash on the end or not. If I use the included patch, it breaks
something in udev. If I patch sysfs_get_mnt_path I break udev as well
because what you're expecting. I need to sit down and go through
the library and creaate a rule as to trailing slashes. Adding the env
brought this to light.
Here's the patch to up the library to the sysfsutils-0_3_0 level. The
following changes:
1) adds class name to sysfs_class_device structure
2) adds bus to sysfs_device
3) gets rid of code that made assumptions as to bus addresses being
unique across buses, which isn't the case.
I still owe you:
1) change getpagesize->sysconf. This is in the CVS tree and part of other
changes we're currently testing. Patch will follow.
2) you need a function to get a sysfs_class_device's parent. We hadn't
considered class devices to have parents, the one example of a multilevel
is the block class. We will add this function and send the patch to you.
On Monday 24 November 2003 01:29, Greg KH wrote:
> I think with the ability to capture the output of the CALLOUT rule,
> combined with the ability to put format modifiers in the CALLOUT program
> string, we now have everything in place to emulate the existing devfs
> naming scheme. Anyone want to verify this or not?
I would prefer to have the ability of creating partition nodes in devfs
style built-in to udev. Devfs used to call the whole disk e.g.
"/dev/dasd/0123/disk" and the partitions "/dev/dasd/0123/part[1-3]".
This can obviously be done with a CALLOUT rule, but its common enough
to make it a format modifier. AFAIK, this scheme has been used for
ide, scsi and dasd disks, which is about 99% of all disks ever connected
to Linux.
udev kept on segfaulting when it was in use, and not having the time
(and building it with DEBUG=true showing nothing), I have not tracked it
until tonight. Seems like I made a type-o, and forgotten the ':'
between one line's group and permission parameters. Attached patch
should stop the segfault, and warn at that at least.
04-udev.8-tweak-numeric-id-text.diff
o change "return value" to "returned string"
o add textual owner/group example for udev.permissions
o mention klibc compile as special case for udev.permissions
o remove duplicated numeric owner clause
