If connect close is fired then following unregister will fail
as we set callback to NULL and thus callback equality checking
will fail.

Callback is set to NULL to make it fired only one time probabaly.
Instead lets use connection equality to NULL to check if callback
is already fired.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

We have reference to connection object in virConnectCloseCallbackData
object thus we have to refcount it. Obviously we have problems
in dispose and call functions. Let's fix it.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

Make register and unregister functions return void because
we can check the state of callback object beforehand via
virConnectCloseCallbackDataGetCallback. This can be done
without race conditions if we use higher level locks for registering
and unregistering. The fact they return void simplifies
task of consistent registering/unregistering.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

This is the key structure of all management operations performed on the
daemon/clients. An admin client needs to be able to identify
another client (either admin or non-privileged client) to perform an
action on it. This identification includes a server the client is
connected to, thus a client-side representation of a server is needed.
Signed-off-by: NErik Skultety <eskultet@redhat.com>

Commmit df8192aa introduced admin related rename and some minor
(caused by automated approach, aka sed) and some more severe isues along with
it. First reason to revert is the inconsistency with libvirt library.
Although we deal with the daemon directly rather than with a specific
hypervisor, we still do have a connection. That being said, contributors might
get under the impression that AdmDaemonNew would spawn/start a new daemon
(since it's admin API, why not...), or AdmDaemonClose would do the exact
opposite or they might expect DaemonIsAlive report overall status of the daemon
which definitely isn't the case.
The second reason to revert this patch is renaming virt-admin client. The
client tool does not necessarily have to reflect the names of the API's it's
using in his internals. An example would be 's/vshAdmConnect/vshAdmDaemon'
where noone can be certain of what the latter function really does. The former
is quite expressive about some connection magic it performs, but the latter does
not say anything, especially when vshAdmReconnect and vshAdmDisconnect were
left untouched.

virAdmConnect was named after virConnect, but after some discussions,
most of the APIs called will be working with remote daemon and starting
them virAdmDaemon will make more sense.  Only possibly controversal name
is CloseCallback (de)registration, and connecting to the daemon (which
will still be Open/Close), but even this makes sense if one thinks about
the daemon being opened and closed, e.g. as file, etc.

This way all the APIs working with the daemon will start with
virAdmDaemon prefix, they will accept virAdmDaemonPtr as first parameter
and that will better suit with other namings as well (virDomain*,
virAdmServer*, etc.).

Because in virt-admin, the connection name does not refer to a struct
that would have a connect in its name, also adjust 'connname' in
clients.  And because it is not used anywhere in the vsh code, move it
from there into each client.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

As we need a client disconnect handler, we also need a mechanism to register
such handlers for a client. This patch introduced both the close callbacks and
also the client vshAdmCatchDisconnect handler to be registered with it. By
registering the handler we still need to make sure the client can react to
daemon's events like disconnect or keepalive, so asynchronous I/O event polling
is necessary to be enabled too.

Since virt-admin should be able to connect to various admin servers
on hosted different daemons, we need to provide URI support to
libvirt-admin.

Initial scratch of the admin library.  It has its own virAdmConnectPtr
that inherits from virAbstractConnectPtr and thus trivially supports
error reporting.

There's pkg-config file added and spec-file adjusted as well.

Since the library should be "minimalistic" and not depend on any other
library, the list of files is especially crafted for it.  Most of them
could've been put to it's own sub-libraries that would be LIBADD'd to
libvirt_util, libvirt_net_rpc and libvirt_setuid_rpc_client to minimize
the number of object files being built, but that's a refactoring that
isn't the orginal aim of this commit.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

It already had a virMutex inside, so this is just a cleanup.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Luckily we are allocating structs as clean memory and
PTHREAD_MUTEX_INITIALIZER is "{ 0 }", so nothing happened, but it should
still be created as lockable object.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Wikipedia's list of common misspellings [1] has a machine-readable
version.  This patch fixes those misspellings mentioned in the list
which don't have multiple right variants (as e.g. "accension", which can
be both "accession" and "ascension"), such misspellings are left
untouched.  The list of changes was manually re-checked for false
positives.

[1] https://en.wikipedia.org/wiki/Wikipedia:Lists_of_common_misspellings/For_machinesSigned-off-by: NMartin Kletzander <mkletzan@redhat.com>

For stateless, client side drivers, it is never correct to
probe for secondary drivers. It is only ever appropriate to
use the secondary driver that is associated with the
hypervisor in question. As a result the ESX & HyperV drivers
have both been forced to do hacks where they register no-op
drivers for the ones they don't implement.

For stateful, server side drivers, we always just want to
use the same built-in shared driver. The exception is
virtualbox which is really a stateless driver and so wants
to use its own server side secondary drivers. To deal with
this virtualbox has to be built as 3 separate loadable
modules to allow registration to work in the right order.

This can all be simplified by introducing a new struct
recording the precise set of secondary drivers each
hypervisor driver wants

struct _virConnectDriver {
    virHypervisorDriverPtr hypervisorDriver;
    virInterfaceDriverPtr interfaceDriver;
    virNetworkDriverPtr networkDriver;
    virNodeDeviceDriverPtr nodeDeviceDriver;
    virNWFilterDriverPtr nwfilterDriver;
    virSecretDriverPtr secretDriver;
    virStorageDriverPtr storageDriver;
};

Instead of registering the hypervisor driver, we now
just register a virConnectDriver instead. This allows
us to remove all probing of secondary drivers. Once we
have chosen the primary driver, we immediately know the
correct secondary drivers to use.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

- As of commit 2ff4c137, all virGet*() functions in datatypes.c always
  return pointers to new objects. Objects are not cached in a
  per-connection hashtable.

- Fix variable names in comments for all vir*Dispose() functions in
  datatypes.c.

- Add comments for virGetStream(), virStreamDispose(),
  virGetDomainSnapshot(), virDomainSnapshotDispose().
Signed-off-by: NMichael Chapman <mike@very.puzzling.org>

Some of these are leftovers from renaming the files, others
are just typos.

Also introduce an ugly awk script to enforce this.

As of commit 46ec5f85, the conn.lock mutex does not need to be held
when calling any vir*Dispose() function in datatypes.c (via virObjectUnref()).
Signed-off-by: NMichael Chapman <mike@very.puzzling.org>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

In datatype.c, virGetDomainSnapshot could result in the message:

error: invalid domain pointer in bad domain

Furthermore, while there are a few functions in libvirt.c that
only care about a virDomainPtr without regards to the connection
(such as virDomainGetName), most functions also require a valid
connection.  Yet several functions were blindly dereferencing
the conn member without checking it for validity first (such as
virDomainOpenConsole).  Rather than try and correct all usage
of VIR_IS_DOMAIN vs. VIR_IS_CONNECTED_DOMAIN, it is easier to
just blindly require that a valid domain object always has a
valid connection object (which should be true anyways, since
every domain object holds a reference to its connection, so the
connection will not be closed until all domain objects have
also been closed to release their reference).

After this patch, all places that validate a domain consistently
report:

error: invalid domain pointer in someFunc

* src/datatypes.h (virCheckDomainReturn, virCheckDomainGoto): New
macros.
* src/datatypes.c (virGetDomainSnapshot): Use new macro.
(virLibConnError): Delete unused macro.
Signed-off-by: NEric Blake <eblake@redhat.com>

The datatype.c object checks could result in a message like:

error: invalid connection pointer in no connection

This consolidates all clients of this message to have uniform contents:

error: invalid connection pointer in someFunc

Note that virCheckConnectReturn raises an error immediately; in
datatypes.c, where we don't need to raise the error (but instead
just leave it in the thread-local setting), we use
virCheckConnectGoto and the cleanup label instead.  Then, for
consistency in that file, all subsequent error messages are
touched to also use the cleanup error label.

* src/datatypes.h (virCheckConnectReturn)
(virCheckConnectGoto): New macros.
* src/datatypes.c: Use new macro.
* src/libvirt-qemu.c (virDomainQemuAttach): Likewise.
(virLibConnError): Delete unused macro.
* src/libvirt-lxc.c (virLibConnError): Likewise.
* src/libvirt.c: Use new macro throughout.
* docs/api_extension.html.in: Modernize documentation.
Signed-off-by: NEric Blake <eblake@redhat.com>

If a OOM error occurs in virGetConnect, this may cause the
virConnectDispose method to de-reference a NULL pointer,
since the close callback will not have been initialized.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

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>