Re: [Libvir] PATCH 15/20: remove use of libsysfs in bridge code
On Fri, Jun 22, 2007 at 03:17:07AM +0100, Daniel P. Berrange wrote:
Sigh, missed another attachment...
On Fri, Jun 22, 2007 at 03:12:11AM +0100, Daniel P. Berrange wrote:
> The current code for setting up bridges in virtual networks links against
> the libsysfs library. This is use to get/set the spanning-tree-protocol and
> forward-delay parameters on the bridge device. None of the four methods
> using libsysfs are ever called though. The fact that the setters are not
> called during network start is a bug. There is no need for getters at all
> since we have the config in memory all the time. The libsysfs is also not
> exactly an ABI stable library - we're unable to compile libvirt on FC5
> for example because of this. This patch changes the bridge code to just
> invoke the brctl command directly which is much more portable & avoids
> the need for us to link libvirt.so against libsysfs.so It also fixes the
> network creation process to actually set STP & forward-delay parameters
> if specified.
I don't have enough expertise to really juge the change from the library
to calling the system command, I like the idea of dropping the dependancy
to the library though.
+#define BRCTL_PATH "/usr/sbin/brctl"
That should probably be tested in configure.in
I wonder what impact it would have for example on Solaris, expert feedback
would be welcome :-)
+ if ((null = open(_PATH_DEVNULL, O_RDONLY)) < 0)
+ return errno;
Hum probably worth raising an error. Though if /dev/null can't
be opened libvirt is probably the last of your worries.
+ char **argv;
+ int retval = ENOMEM;
+ int n;
+
+ n = 1 + /* brctl */
+ 1 + /* setfd */
+ 1 + /* brige name */
+ 1; /* value */
1; /* NULL */
and then calloc with n instead, let's describe fully.
+
+ if (!(argv = (char **)calloc(n + 1, sizeof(char *))))
+ goto error;
I'm fine with the patch to the extend I understand it implications +1
Daniel
--
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Daniel Veillard | virtualization library http://libvirt.org/
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