The function takes pool name as argument. However,
it is not acceptable for it to be NULL. Hence, we
should check it and report error in case it is.

The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.

It will simplify later work if the sub-drivers have dedicated
APIs / field names. ie virNetworkDriver should have
virDrvNetworkOpen and virDrvNetworkClose methods
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The driver.h struct for node devices used an inconsistent
naming scheme 'DeviceMonitor' instead of the more usual
'NodeDeviceDriver'. Fix this everywhere it has leaked
out to.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Ensure that the driver struct field names match the public
API names. For an API virXXXX we must have a driver struct
field xXXXX. ie strip the leading 'vir' and lowercase any
leading uppercase letters.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The last Viktor's effort to fix the race and memory corruption unfortunately
wasn't complete in the case the close callback was not registered in an
connection. At that time, the trail of event's that I'll describe later could
still happen and corrupt the memory or cause a crash of the client (including
the daemon in case of a p2p migration).

Consider the following prerequisities and trail of events:
Let's have a remote connection to a hypervisor that doesn't have a close
callback registered and the client is using the event loop. The crash happens in
cooperation of 2 threads. Thread E is the event loop and thread W is the worker
that does some stuff. R denotes the remote client.

1.) W - The client finishes everything and sheds the last reference on the client
2.) W - The virObject stuff invokes virConnectDispose that invokes doRemoteClose
3.) W - the remote close method invokes the REMOTE_PROC_CLOSE RPC method.
4.) W - The thread is preempted at this point.
5.) R - The remote side receives the close and closes the socket.
6.) E - poll() wakes up due to the closed socket and invokes the close callback
7.) E - The event loop is preempted right before remoteClientCloseFunc is called
8.) W - The worker now finishes, and frees the conn object.
9.) E - The remoteClientCloseFunc accesses the now-freed conn object in the
        attempt to retrieve pointer for the real close callback.
10.) Kaboom, corrupted memory/segfault.

This patch tries to fix this by introducing a new object that survives the
freeing of the connection object. We can't increase the reference count on the
connection object itself or the connection would never be closed, as the
connection is closed only when the reference count reaches zero.

The new object - virConnectCloseCallbackData - is a lockable object that keeps
the pointers to the real user registered callback and ensures that the
connection callback is either not called if the connection was already freed or
that the connection isn't freed while this is being called.

Currently all classes must directly inherit from virObject.
This allows for arbitrarily deep hierarchy. There's not much
to this aside from chaining up the 'dispose' handlers from
each class & providing APIs to check types.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This will simplify the refactoring of the ESX storage driver to support
a VMFS and an iSCSI backend.

One of the tasks the storage driver needs to do is to decide which backend
driver needs to be invoked for a given request. This approach extends
virStoragePool and virStorageVol to store extra parameters:

1. privateData: stores pointer to respective backend storage driver.
2. privateDataFreeFunc: stores cleanup function pointer.

virGetStoragePool and virGetStorageVol are modfied to accept these extra
parameters as user params. virStoragePoolDispose and virStorageVolDispose
checks for cleanup operation if available.

The private data pointer allows the ESX storage driver to store a pointer
to the used backend with each storage pool and volume. This avoids the need
to detect the correct backend in each storage driver function call.

https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.

* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/;  If/.  If/

This converts the following public API datatypes to use the
virObject infrastructure:

  virConnectPtr
  virDomainPtr
  virDomainSnapshotPtr
  virInterfacePtr
  virNetworkPtr
  virNodeDevicePtr
  virNWFilterPtr
  virSecretPtr
  virStreamPtr
  virStorageVolPtr
  virStoragePoolPtr

The code is significantly simplified, since the mutex in the
virConnectPtr object now only needs to be held when accessing
the per-connection virError object instance. All other operations
are completely lock free.

* src/datatypes.c, src/datatypes.h, src/libvirt.c: Convert
  public datatypes to use virObject
* src/conf/domain_event.c, src/phyp/phyp_driver.c,
  src/qemu/qemu_command.c, src/qemu/qemu_migration.c,
  src/qemu/qemu_process.c, src/storage/storage_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xend_internal.c,
  tests/qemuxml2argvtest.c, tests/qemuxmlnstest.c,
  tests/sexpr2xmltest.c, tests/xmconfigtest.c: Convert
  to use virObjectUnref/virObjectRef
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Several APIs in src/datatypes.c were formatting an UUID to a
uuidstr variable and then not using it.

Define new virConnect{Register,Unregister}CloseCallback() public APIs
which allows registering/unregistering a callback to be invoked when
the connection to a hypervisor is closed. The callback is provided
with the reason for the close, which may be 'error', 'eof', 'client'
or 'keepalive'.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Any time we have a string with no % passed through gettext, a
translator can inject a % to cause a stack overread.  When there
is nothing to format, it's easier to ask for a string that cannot
be used as a formatter, by using a trivial "%s" format instead.

In the past, we have used --disable-nls to catch some of the
offenders, but that doesn't get run very often, and many more
uses have crept in.  Syntax check to the rescue!

The syntax check can catch uses such as
virReportError(code,
               _("split "
                 "string"));
by using a sed script to fold context lines into one pattern
space before checking for a string without %.

This patch is just mechanical insertion of %s; there are probably
several messages touched by this patch where we would be better
off giving the user more information than a fixed string.

* cfg.mk (sc_prohibit_diagnostic_without_format): New rule.
* src/datatypes.c (virUnrefConnect, virGetDomain)
(virUnrefDomain, virGetNetwork, virUnrefNetwork, virGetInterface)
(virUnrefInterface, virGetStoragePool, virUnrefStoragePool)
(virGetStorageVol, virUnrefStorageVol, virGetNodeDevice)
(virGetSecret, virUnrefSecret, virGetNWFilter, virUnrefNWFilter)
(virGetDomainSnapshot, virUnrefDomainSnapshot): Add %s wrapper.
* src/lxc/lxc_driver.c (lxcDomainSetBlkioParameters)
(lxcDomainGetBlkioParameters): Likewise.
* src/conf/domain_conf.c (virSecurityDeviceLabelDefParseXML)
(virDomainDiskDefParseXML, virDomainGraphicsDefParseXML):
Likewise.
* src/conf/network_conf.c (virNetworkDNSHostsDefParseXML)
(virNetworkDefParseXML): Likewise.
* src/conf/nwfilter_conf.c (virNWFilterIsValidChainName):
Likewise.
* src/conf/nwfilter_params.c (virNWFilterVarValueCreateSimple)
(virNWFilterVarAccessParse): Likewise.
* src/libvirt.c (virDomainSave, virDomainSaveFlags)
(virDomainRestore, virDomainRestoreFlags)
(virDomainSaveImageGetXMLDesc, virDomainSaveImageDefineXML)
(virDomainCoreDump, virDomainGetXMLDesc)
(virDomainMigrateVersion1, virDomainMigrateVersion2)
(virDomainMigrateVersion3, virDomainMigrate, virDomainMigrate2)
(virStreamSendAll, virStreamRecvAll)
(virDomainSnapshotGetXMLDesc): Likewise.
* src/nwfilter/nwfilter_dhcpsnoop.c (virNWFilterSnoopReqLeaseDel)
(virNWFilterDHCPSnoopReq): Likewise.
* src/openvz/openvz_driver.c (openvzUpdateDevice): Likewise.
* src/openvz/openvz_util.c (openvzKBPerPages): Likewise.
* src/qemu/qemu_cgroup.c (qemuSetupCgroup): Likewise.
* src/qemu/qemu_command.c (qemuBuildHubDevStr, qemuBuildChrChardevStr)
(qemuBuildCommandLine): Likewise.
* src/qemu/qemu_driver.c (qemuDomainGetPercpuStats): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainAttachNetDevice): Likewise.
* src/rpc/virnetsaslcontext.c (virNetSASLSessionGetIdentity):
Likewise.
* src/rpc/virnetsocket.c (virNetSocketNewConnectUNIX)
(virNetSocketSendFD, virNetSocketRecvFD): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskBuildPool): Likewise.
* src/storage/storage_backend_fs.c
(virStorageBackendFileSystemProbe)
(virStorageBackendFileSystemBuild): Likewise.
* src/storage/storage_backend_rbd.c
(virStorageBackendRBDOpenRADOSConn): Likewise.
* src/storage/storage_driver.c (storageVolumeResize): Likewise.
* src/test/test_driver.c (testInterfaceChangeBegin)
(testInterfaceChangeCommit, testInterfaceChangeRollback):
Likewise.
* src/vbox/vbox_tmpl.c (vboxListAllDomains): Likewise.
* src/xenxs/xen_sxpr.c (xenFormatSxprDisk, xenFormatSxpr):
Likewise.
* src/xenxs/xen_xm.c (xenXMConfigGetUUID, xenFormatXMDisk)
(xenFormatXM): Likewise.

Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)

  You should have received a copy of the GNU General Public License
  along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').

Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:

  src/security/security_selinux.h
  src/security/security_driver.h
  src/security/security_selinux.c
  src/security/security_apparmor.h
  src/security/security_apparmor.c
  src/security/security_driver.c

To ensure consistent error reporting of invalid arguments,
provide a number of predefined helper methods & macros.

 - An arg which must not be NULL:

   virCheckNonNullArgReturn(argname, retvalue)
   virCheckNonNullArgGoto(argname, label)

 - An arg which must be NULL

   virCheckNullArgGoto(argname, label)

 - An arg which must be positive (ie 1 or greater)

   virCheckPositiveArgGoto(argname, label)

 - An arg which must not be 0

   virCheckNonZeroArgGoto(argname, label)

 - An arg which must be zero

   virCheckZeroArgGoto(argname, label)

 - An arg which must not be negative (ie 0 or greater)

   virCheckNonNegativeArgGoto(argname, label)

* src/libvirt.c, src/libvirt-qemu.c,
  src/nodeinfo.c, src/datatypes.c: Update to use
  virCheckXXXX macros
* po/POTFILES.in: Add libvirt-qemu.c and virterror_internal.h
* src/internal.h: Define macros for checking invalid args
* src/util/virterror_internal.h: Define macros for reporting
  invalid args
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Return statements with parameter enclosed in parentheses were modified
and parentheses were removed. The whole change was scripted, here is how:

List of files was obtained using this command:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$'

Found files were modified with this command:
sed -i -e                                                                 \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'

Then checked for nonsense.

The whole command looks like this:
git grep -l -e '\<return\s*([^()]*\(([^()]*)[^()]*\)*)\s*;' |             \
grep -e '\.[ch]$' -e '\.py$' | xargs sed -i -e                            \
's_^\(.*\<return\)\s*(\(\([^()]*([^()]*)[^()]*\)*\))\s*\(;.*$\)_\1 \2\4_' \
-e 's_^\(.*\<return\)\s*(\([^()]*\))\s*\(;.*$\)_\1 \2\3_'

Since we defined a custom virURIPtr type, we should use a
virURIFree method instead of assuming it will always be
a typedef for xmlURIPtr

* src/util/viruri.c, src/util/viruri.h, src/libvirt_private.syms:
  Add a virURIFree method
* src/datatypes.c, src/esx/esx_driver.c, src/libvirt.c,
  src/qemu/qemu_migration.c, src/vmx/vmx.c, src/xen/xend_internal.c,
  tests/viruritest.c: s/xmlFreeURI/virURIFree/
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

POSIX allows implementations where PATH_MAX is undefined, leading
to compilation error.  Not to mention that even if it is defined,
it is often wasteful in relation to the amount of data being stored.

All clients of vol->key were audited, and found not to care about
whether key is static or dynamic, except for these offenders:

* src/datatypes.h (struct _virStorageVol): Manage key dynamically.
* src/datatypes.c (virReleaseStorageVol): Free key.
(virGetStorageVol): Copy key.

And from all related macros and functions.

Done mechanically with:
$ git grep -l '\bDEBUG0\? *(' | xargs -L1 sed -i 's/\bDEBUG0\? *(/VIR_&/'

followed by manual deletion of qemudDebug in daemon/libvirtd.c, along
with a single 'make syntax-check' fallout in the same file, and the
actual deletion in src/util/logging.h.

* src/util/logging.h (DEBUG, DEBUG0): Delete.
* daemon/libvirtd.h (qemudDebug): Likewise.
* global: Change remaining clients over to VIR_DEBUG counterpart.

The virConnectPtr struct will cache instances of all other
objects. APIs like virDomainLookupByUUID will return a
cached object, so if you do virDomainLookupByUUID twice in
a row, you'll get the same exact virDomainPtr instance.

This does not have any performance benefit, since the actual
logic in virDomainLookupByUUID (and other APIs returning
virDomainPtr, etc instances) is not short-circuited. All
it does is to ensure there is only one single virDomainPtr
in existance for any given UUID.

The caching has a number of downsides though, all relating
to stale data. If APIs aren't careful to always overwrite
the 'id' field in virDomainPtr it may become out of data.
Likewise for the name field, if a guest is renamed, or if
a guest is deleted, and then a new one created with the
same UUID but different name.

This has been an ongoing, endless source of bugs for all
applications using libvirt from languages with garbage
collection, causing them to get virDomainPtr instances
from long ago with stale data.

The caching is also a waste of memory resources, since
both applications, and language bindings often maintain
their own hashtable caches of object instances.

This patch removes all the hash table caching, so all
APIs return brand new virDomainPtr (etc) object instances.

* src/datatypes.h: Delete all hash tables.
* src/datatypes.c: Remove all object caching code

There were several occurrences of an extra space inserted between
a function name and the ( opening the argument list in
datatypes.c. This is not consistent with the coding style used in
the rest of this file so removing this extra space makes the
code slightly more readable.

virHashFree follows the convention described in HACKING that
XXXFree() functions can be called with a NULL argument.

When creating the virDomain::snapshots hash table, virGetDomain
wasn't checking if the creation was successful. This would then
lead to failures in the vir*DomainSnapshot functions. Better to
report this error early and make virGetDomain fail if the
snapshots hash couldn't be created.
* src/datatypes.c: report failure to make a hash table

commit f1fe9671 was supposed to make sure we use files.h
macros to avoid double close, but it didn't work.

Meanwhile, virCommand is vastly superior to system(), fork(),
and popen() (also to virExec, but we haven't completed that
conversion), so enforce that, too.

* cfg.mk (sc_prohibit_close): Fix typo that excluded close, and
add pclose.
(sc_prohibit_fork_wrappers): New rule, for fork, system, and popen.
* .x-sc_prohibit_close: More exemptions.
* .x-sc_prohibit_fork_wrappers: New file.
* Makefile.am (syntax_check_exceptions): Ship new file.
* src/datatypes.c (virReleaseConnect): Tweak comment to avoid
false positive.
* src/util/files.h (VIR_CLOSE): Likewise.

The public object is called NWFilter but the corresponding private
object is called NWFilterPool. I don't see compelling reasons for this
Pool suffix. One might argue that an NWFilter is a "pool" of rules, etc.

Remove the Pool suffix from NWFilterPool. No functional change included.

virLibConnError already includes __FUNCTION__ in its output, so we
were redundant.  Furthermore, clang warns that __FUNCTION__ is not
a string literal (at least __FUNCTION__ will never contain %, so
it was not a security risk).

* src/datatypes.c: Replace __FUNCTION__ with a descriptive string.

virConnectClose calls virUnrefConnect which in turn closes
all open drivers when the refcount of that connection dropped
to zero. This works fine when you free all other objects that
hold a ref to the connection before you close it, because in
this case virUnrefConnect is the one that removes the last
ref to the connection.

But it doesn't work when you close the connection first before
freeing the other objects. This is because the other virUnref*
functions call virReleaseConnect when they detect that the
connection's refcount dropped to zero. In this case another
virUnref* function (different from virUnrefConnect) removes the
last ref to the connection. This results in not closing the
open drivers and leaking things that should have been cleaned
up in the driver close functions.

To fix this move the driver close calls to virReleaseConnect.

- Fix documentation for virGetStorageVol: it has 'key' argument instead
  of 'uuid'.
- Remove TODO comment from virReleaseStorageVol: we use volume key as an
  identifier instead of UUID.
- Print human-readable UUID string in debug message in virReleaseSecret.

As anywhere else, uuid is defined as a fixed size array inside
_virSecret structure; we shouldn't try to free it.

The first thing we do in all these functions is to check uuid != NULL
and fail if it isn't.