virHostdevRestoreNetConfig() calls virNetDevReadNetConfig() to try and read the "original config" of a netdev, and if that fails, it tries again with a different directory/netdev name. This achieves the desired effect (we end up finding the config wherever it may be), but for each failure, virNetDevReadNetConfig() places a nice error message in the system logs. Experience has shown that false-positive error logs like this lead to erroneous bug reports, and can often mislead those searching for *real* bugs. This patch changes virNetDevReadNetConfig() to explicitly check if the file exists before calling virFileReadAll(); if it doesn't exist, virNetDevReadNetConfig() returns a success, but leaves all the variables holding the results as NULL. (This makes sense if you define the purpose of the function as "read a netdev's config from its config file *if that file exists*). To take advantage of that change, the caller, virHostdevRestoreNetConfig() is modified to fail immediately if virNetDevReadNetConfig() returns an error, and otherwise to try the different directory/netdev name if adminMAC & vlan & MAC are all NULL after the preceding attempt.
Libvirt API for virtualization
Libvirt provides a portable, long term stable C API for managing the virtualization technologies provided by many operating systems. It includes support for QEMU, KVM, Xen, LXC, bhyve, Virtuozzo, VMware vCenter and ESX, VMware Desktop, Hyper-V, VirtualBox and the POWER Hypervisor.
For some of these hypervisors, it provides a stateful management daemon which runs on the virtualization host allowing access to the API both by non-privileged local users and remote users.
Layered packages provide bindings of the libvirt C API into other languages including Python, Perl, PHP, Go, Java, OCaml, as well as mappings into object systems such as GObject, CIM and SNMP.
Further information about the libvirt project can be found on the website:
License
The libvirt C API is distributed under the terms of GNU Lesser General
Public License, version 2.1 (or later). Some parts of the code that are
not part of the C library may have the more restrictive GNU General
Public License, version 2.1 (or later). See the files COPYING.LESSER
and COPYING
for full license terms & conditions.
Installation
Libvirt uses the GNU Autotools build system, so in general can be built and installed with the usual commands. For example, to build in a manner that is suitable for installing as root, use:
$ ./configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
$ make
$ sudo make install
While to build & install as an unprivileged user
$ ./configure --prefix=$HOME/usr
$ make
$ make install
The libvirt code relies on a large number of 3rd party libraries. These will
be detected during execution of the configure
script and a summary printed
which lists any missing (optional) dependencies.
Contributing
The libvirt project welcomes contributions in many ways. For most components the best way to contribute is to send patches to the primary development mailing list. Further guidance on this can be found on the website:
https://libvirt.org/contribute.html
Contact
The libvirt project has two primary mailing lists:
- libvirt-users@redhat.com (for user discussions)
- libvir-list@redhat.com (for development only)
Further details on contacting the project are available on the website: