Commit d2a929d4 (0.9.4) defined virDomainSaveImageGetXMLDesc()'s use of @flags as a subset of virDomainXMLFlags, documenting that 2 of the 3 flags defined at the time would never be valid. Later, commit 28f8dfdc (1.0.0) introduced a new flag, VIR_DOMAIN_XML_MIGRATABLE, but did not adjust the save image documentation to declare it as invalid. Later, commit a67e3872 (3.7.0) blindly copied and pasted the same text into virDomainManagedSaveGetXMLDesc. However, since the flag is not accepted as valid by any of the drivers (remote is just passthrough; and qemu is the only supporting driver for either API, with support for just VIR_DOMAIN_XML_SECURE), it is easier to just define an explicit set of supported flags directly related to the save image API rather than trying to borrow from live domain API, and risking confusion if even more domain flags are added later (in fact, I have an upcoming patch that plans to add a new flag to virDomainGetXMLDesc that makes no sense for saved images). We may someday decide that saved images need to support the _MIGRATABLE flag, as it is possible to load a saved image with a different version of libvirt than the one that created it, but that can be a separate patch if it is ever needed. Meanwhile, it DOES make sense to reuse the same flags for SaveImage and for ManagedSave (since ManagedSave is really just sugar for creating a normal SaveImage in a location controlled by libvirt instead of by the user). There is no API or ABI impact (since we purposefully used unsigned int rather than an enum type in public API, and since the new flag name carries the same value as the old reused name). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Ferlan <jferlan@redhat.com>
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: