Nearly all of the methods in src/util/util.h have error codes that
must be checked by the caller to correct detect & report failure.
Add ATTRIBUTE_RETURN_CHECK to ensure compile time validation of
this

* daemon/libvirtd.c: Add explicit check on return value of virAsprintf
* src/conf/domain_conf.c: Add missing check on virParseMacAddr return
  value status & report error
* src/network/bridge_driver.c: Add missing OOM check on virAsprintf
  and report error
* src/qemu/qemu_conf.c: Add missing check on virParseMacAddr return
  value status & report error
* src/security/security_selinux.c: Remove call to virRandomInitialize
  that's done in libvirt.c already
* src/storage/storage_backend_logical.c: Add check & log on virRun
  return status
* src/util/util.c: Add missing checks on virAsprintf/Run status
* src/util/util.h: Annotate all methods with ATTRIBUTE_RETURN_CHECK
  if they return an error status code
* src/vbox/vbox_tmpl.c: Add missing check on virParseMacAddr
* src/xen/xm_internal.c: Add missing checks on virAsprintf
* tests/qemuargv2xmltest.c: Remove bogus call to virRandomInitialize()

* src/qemu/qemu_conf.c: change the error message to refer to
  'cgroup_controllers' instead of 'cgroup_device_acl'

This adds simple support for configuring a guest with a QEMU/KVM
virtual hardware watchdog device.

If the the qemu and kvm binaries are the same, we don't include machine
types in the kvm domain info.

However, the code which refreshes the machine types info from the
previous capabilities structure first looks at the kvm domain's info,
finds it matches and then copies the empty machine types list over
for the top-level qemu domain.

That doesn't make sense, we shouldn't copy an empty machin types list.

* src/qemu/qemu_conf.c: qemudGetOldMachinesFromInfo(): don't copy an
  empty machine types list.

Signed-off-by: NChris Lalancette <clalance@redhat.com>

When using VNC for graphics + keyboard + mouse, we shouldn't
then use the host OS for audio. Audio should go back over
VNC.

When using SDL for graphics, we should use the host OS for
audio since that's where the display is. We need to allow
certain QEMU env variables to be passed through to guest
too to allow choice of QEMU audio backend.

* qemud/libvirtd.sysconf: Mention QEMU/SDL audio env vars
* src/qemu_conf.c: Passthrough QEMU/SDL audio env for SDL display,
  disable host audio for VNC display

* src/qemu/qemu_conf.h, src/qemu/qemu_conf.c: Remove prefix arg
  from qemuBuildHostNetStr which is no longer required
* src/qemu/qemu_driver.c: Refactor to use qemuMonitorAddHostNetwork()
  API for adding host network
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorAddHostNetwork() method for adding host networks

* src/qemu/qemu_conf.c: Remove separator from qemuBuildNicStr()
  args, and remove hardcoded 'nic' prefix. Leave it upto callers
  instead
* src/qemu/qemu_driver.c: Switch over to using the new
  qemuMonitorAddPCINetwork() method for NIC hotplug
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorAddPCINetwork API for PCI network device hotplug

Add the virStrncpy function, which takes a dst string, source string,
the number of bytes to copy and the number of bytes available in the
dest string.  If the source string is too large to fit into the
destination string, including the \0 byte, then no data is copied and
the function returns NULL.  Otherwise, this function copies n bytes
from source into dst, including the \0, and returns a pointer to the
dst string.  This function is intended to replace all unsafe uses
of strncpy in the code base, since strncpy does *not* guarantee that
the buffer terminates with a \0.
Signed-off-by: NChris Lalancette <clalance@redhat.com>

Latest upstream QEMU can be built with Xen support, which introduces
a -xen-domid argument. This was  mistakenly detected as -domid due
to old Xenner support. Adapt to cope with both syntax. Also only
set domid if the virt type is xen, or the guest type is xen

* src/qemu_conf.c, src/qemu_conf.h: Detect new -xen-domid flag in
  preference to -domid.
* tests/qemuxml2argvdata/qemuxml2argv-bootloader.args,
  tests/qemuxml2argvdata/qemuxml2argv-input-xen.args: Add missing
  -domid param
* tests/qemuxml2argvdata/qemuxml2argv-misc-uuid.args: Remove bogus
  -boot param.
* tests/qemuxml2argvtest.c: Add missing QEMUD_CMD_FLAG_DOMID params

Signed-off-by: NChris Lalancette <clalance@redhat.com>

* src/qemu_conf.c, src/qemu_conf.h, src/qemu_driver.c,
  src/qemu_driver.h: Move to src/qemu/
* daemon/qemud.c, src/Makefile.am, tests/qemuargv2xmltest.c,
  tests/qemuhelptest.c, tests/qemuxml2argvtest.c,
  tests/qemuxml2xmltest.c: Adapt for changed paths

* src/qemu_conf.c: Fix leak of values upon OOM
* src/xend_internal.c: Fix missing check for OOM failure
* tests/qemuargv2xmltest.c, tests/qemuxml2argvtest.c: Free
  stateDir upon exit to avoid leak

Currently we only probe the main qemu binary for machine types, but we
should also probe the kvm binary.

* src/qemu_conf.c: probe kvm binary machines in qemudCapsInitGuest()

Rather than just looking at the default domain info, look at all
domains

* src/qemu_conf.c: look at all domains in qemudGetOldMachines()

We need to look at all the domain infos in guest capabilities, not
just the defaults.

In order to allow that, split out a qemudGetOldMachinesFromInfo()
from qemudGetOldMachines(). We'll make more use of it in the next
patch.

* src/qemu_conf.c: split out qemudGetOldMachinesFromInfo() from
  qemudGetOldMachines()

* src/qemu_conf.c (qemuBuildHostNetStr): Do not remove the type_sep=','
dead store, since not having it would be a problem if we ever add a
new attribute=VAL option.

* src/domain_conf.c src/network_conf.c src/qemu_conf.c
  src/storage_backend_fs.c: various problems spotted by valgrind
  through libvirt code

* docs/schemas/domain.rng: Add <serial> element to disks
* src/domain_conf.h, src/domain_conf.c: XML parsing and
  formatting for disk serial numbers
* src/qemu_conf.c: Set serial number when launching guests
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-shared.args,
  tests/qemuxml2argvdata/qemuxml2argv-disk-drive-shared.xml: Add
  serial number to XML test

Add option to domain XML for

     <memoryBacking>
        <hugepages/>
     </memoryBacking>

* configure.in: Add check for mntent.h
* qemud/libvirtd_qemu.aug, qemud/test_libvirtd_qemu.aug, src/qemu.conf
  Add 'hugetlbfs_mount' config parameter
* src/qemu_conf.c, src/qemu_conf.h: Check for -mem-path flag in QEMU,
  and pass it when hugepages are requested.
  Load hugetlbfs_mount config parameter, search for mount if not given.
* src/qemu_driver.c: Free hugetlbfs_mount/path parameter in driver shutdown.
  Create directory for QEMU hugepage usage, chowning if required.
* docs/formatdomain.html.in: Document memoryBacking/hugepages elements
* docs/schemas/domain.rng: Add memoryBacking/hugepages elements to schema
* src/util.c, src/util.h, src/libvirt_private.syms: Add virFileFindMountPoint
  helper API
* tests/qemuhelptest.c: Add -mem-path constants
* tests/qemuxml2argvtest.c, tests/qemuxml2xmltest.c: Add tests for hugepage
  handling
* tests/qemuxml2argvdata/qemuxml2argv-hugepages.xml,
  tests/qemuxml2argvdata/qemuxml2argv-hugepages.args: Data files for
  hugepage tests

* src/qemu_conf.c, src/uml_conf.c: use virReportSystemError() to report
  system errors

https://bugzilla.redhat.com/517371

Matt Booth points out that if you use a non-existent bridge name when
start a guest you get a weird error message:

  Failed to add tap interface 'vnet%d' to bridge 'virbr0'

and dev='vnet%d' appears in the dumpxml output.

Fix that by not including 'vnet%d' in the error message and freeing the
'vnet%d' string if adding the tap device to the bridge fails.

* src/qemu_conf.c, src/uml_conf.c: fix qemudNetworkIfaceConnect()
  and umlConnectTapDevice() to not expose 'vnet%d' to the user

Implement a compressed save image format for qemu.  While ideally
we would have the choice between compressed/non-compressed
available to the libvirt API, unfortunately there is no "flags"
parameter to the virDomainSave() API.  Therefore, implement this
as a qemu.conf option.  gzip, bzip2, and lzma are implemented, and
it should be very easy to implement additional compression
methods.

One open question is if/how we should detect the compression
binaries.  One way to do it is to do compile-time setting of the
paths (via configure.in), but that doesn't seem like a great thing
to do.  My preferred solution is not to detect at all;
when we go to run the commands that need them, if they
aren't available, or aren't available in one of the standard paths,
then we'll fail.  That's also the solution implemented in this patch.

In the future, we'll have a more robust (managed) save/restore API,
at which time we can expose this functionality properly in the API.

V2: get rid of redundant dd command and just use >> to append data.
V3: Add back the missing pieces for the enum and bumping the save version.
V4: Make the compressed field in the save_header an int.
    Implement LZMA compression.
Signed-off-by: NChris Lalancette <clalance@redhat.com>

PCI device assignment is only supported in KVM's fork of qemu, so we
should really detect its availability and give a nice error if its
not supported.

* src/qemu_conf.[ch]: introduce QEMUD_CMD_FLAG_PCIDEVICE indicating
  that the -pcidevice command line option is available

* tests/*: update the tests

* docs/schemas/*.rng: the comments were wrong
* src/qemu_conf.c: typo in an error message

With hotplug, we're going to want to pass a tapfd name rather than an
actual file descriptor, so prepare the way by passing a string tapfd to
qemuBuildHostNetStr().

* src/qemu_conf.h: qemuBuildHostNetStr() takes a string tapfd now

* src/qemu_conf.c: pass qemuBuildHostNetStr() a string rather than an
  actual file descriptor

* src/qemu_driver.c: update qemudDomainAttachNetDevice() for change

* src/qemu_conf.h: export qemudNetworkIfaceConnect()

* src/qemu_conf.c: move vnet_hdr logic into qemudNetworkIfaceConnect()
  since we need it for hotplug too

By probing for qemu machine types, we increased the time of a
GetCapabilities call from 100us to a whopping 60ms.

This patch takes the approach of only probing for machine types
when the mtime of the emulator binary changed since the last time
the capabilities were generated.

* src/capabilities.h: cache the emulator binary mtime

* src/qemu_conf.c: add qemudGetOldMachines() to copy the machine
  types from the old caps struct if the mtime for the binary hasn't
  changed

* src/qemu_conf.h, src/qemu_driver.c: pass the old caps pointer to
  qemudCapsInit()

Not all possible emulators are actually in the capabilities, so if we
don't find the supplied emulator we should probe it directly for machine
types.

* src/qemu_driver.c: add qemudCanonicalizeMachineDirect() to directly
  probe an emulator for the canonical machine type

In qemu-0.11 there is a 'pc-0.10' machine type which allows you to run
guests with a machine which is compatible with the pc machine in
qemu-0.10 - e.g. using the original PCI class for virtio-blk and
virtio-console and disabling MSI support in virtio-net. The idea here
is that we don't want to suprise guests by changing the hardware when
qemu is updated.

I've just posted some patches for qemu-0.11 which allows libvirt to
canonicalize the 'pc' machine alias to the latest machine version.

This patches makes us use that so that when a guest is configured to
use the 'pc' machine type, we resolve that to 'pc-0.11' machine and
save that in the guest XML.

See also:

  https://fedoraproject.org/wiki/Features/KVM_Stable_Guest_ABI

* src/qemu_conf.c: add qemudCanonicalizeMachine() to canonicalize
  the machine type according to the machine aliases in capabilities

* src/qemu_driver.c: parse aliases in qemudParseMachineTypesStr()

A subsequent commit will add a "canonical" field to this structure,
this patch basically just prepares the way for that.

The new type is added, along with virCapabilitiesAlloc/FreeMachines()
helpers and a whole bunch of code to make the transition.

One quirk is that virCapabilitiesAddGuestDomain() and
virCapabilitiesAddGuest() take ownership of the machine list rather
than duping it. This makes sense to avoid needless copying.

* src/capabilities.h: add the virCapsGuestMachine struct and use it
  in virCapsGuestDomainInfo, add prototypes for new functions and
  update the AddGuest() prototypes

* src/capabilities.c: add code for allocating and freeing the new
  type, change the machines parameter to AddGuest() etc.

* src/libvirt_private.syms: export the new helpers

* src/qemu_conf.c: update all the machine type code to use the new
  struct

* src/xen_internal.c: ditto

* tests/testutilsqemu.c: ditto

Currently we hardcode the QEMU machine types. We should really just
parse the output of 'qemu -M ?' so the lists don't get out of sync.

xenner doesn't support '-M ?', so we still need to hardcode that.

The horrible (const char *const *) is removed in a subsequent patch.

* src/qemu_conf.c: kill the arch_info*machines tables, retain the
  hardcoded xenner machine type, add qemudProbeMachineTypes() to
  run and parse 'qemu -M ?' and use it in qemudCapsInitGuest()

There's no need for the hasbase/hasaltbase confusion, just store the
first binary path found in a variable.

* src/qemu_conf.c: kill hasbase/hasaltbase logic in qemudCapsInitGuest()

 * qemud/libvirtd_qemu.aug, qemud/test_libvirtd_qemu.aug,
   src/qemu.conf: Add 'cgroups_controllers' and 'cgroups_device_acl'
   parameters
 * src/qemu_conf.h, src/qemu_conf.c: Load & parse configuration params
   for cgroups
 * src/qemu_driver.c: Only use cgroups controllers that are activated,
   and use configured device whitelist instead of default, if set.

If the qemu binary supports "-no-kvm" and/or "-no-kqemu", they should
always be added for plain "qemu" domains.  Previously, we omitted them
whenever the host and guest architectures implied that they would be
disabled automatically, but that logic was flawed in some cases
(such as i686 and x86_64).
* src/qemu_conf.c: fix the conditions for adding "-no-kvm" and/or "-no-kqemu"

Implement basic NIC hotplug support using the 'host_net_add' and
'pci_add' qemu monitor commands.

For now, we don't support 'bridge' or 'network' types.

Also, if pci_add fails, we currently fail to remove the backend
which we added.

Finally, NIC hot-unplug support is missing.

* src/qemu_driver.c: add qemudDomainAttachNetDevice()

* src/qemu_conf.[ch]: export qemuBuildNicStr(), qemuBuildHostNetStr()
  and qemuAssignNames()

* src/libvirt_private.syms: export virDomainNetTypeToString()

Currently, an interface's vlan number corresponds to its index in
the table of network interfaces. That is no longer true when we
allow devices to be removed.

To fix this, we store the vlan number in the domain's state XML
so that it survives libvirtd restarts.

* src/domain_conf.h: add vlan number to virDomainNetDef

* src/domain_conf.c: store it in XML as <state vlan='N'/>, defaulting
  to -1 if this is state saved by a previous version of libvirt

* src/qemu_conf.c: assign vlan numbers before starting qemu

We need these so that we can remove the devices via the monitor.

* src/domain_conf.h: add nic_name and hostnet_name to virDomainNetDef

* src/domain_conf.c: free nic_name and hostnet_name

* src/qemu_conf.c: add qemuAssignNetNames(), use it if qemu has
  support for the param and pass the names on the command line

* tests/qemuxml2argv*: add a test for this

Add QEMUD_CMD_FLAG_NET_NAME to indicate that '-net ...,name=foo' is
supported and QEMUD_CMD_FLAG_HOST_NET_ADD to indicate that the
'host_net_add' monitor command is available.

Set both these flags if the qemu version is greater than 0.10.0.
Checking via the '-help' output would not work for the monitor command
and even for the command line arg, it would be quite fragile.

* src/qemu_conf.h: add new flags as aliases of QEMUD_CMD_FLAG_0_10

* src/qemu_conf.c: set QEMUD_CMD_FLAG_0_10 for versions >= 0.10.0

* tests/qemuhelptest.c: set QEMUD_CMD_FLAG_0_10 for the appropriate
  qemu versions

Re-factor this code so that it can be used for NIC hotplug
too. The awkward prefix and type_sep arguments are needed to
allow us to do "host_net_add tap vlan=..."

* src/qemu_conf.c: factor the net backend string formatting
  code into its own function