This function will fetch previously processed stream holes and
return their sum.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This is a function that handles an incoming STREAM_HOLE packet.
Even though it is not wired up yet, it will be soon. At the
beginning do couple of checks whether server plays nicely and
sent us a STREAM_HOLE packed only after we've enabled sparse
streams. Then decodes the message payload to see how big the hole
is and stores it in passed @length argument.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

While the previous commit implemented a helper for sending a
STREAM_HOLE packet for daemon, this is a client's counterpart.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Add a new argument to daemonCreateClientStream in order to allow for
future expansion to mark that a specific stream can be used to skip
data, such as the case with sparsely populated files. The new flag will
be the eventual decision point between client/server to decide whether
both ends can support and want to use sparse streams.

A new bool 'allowSkip' is added to both _virNetClientStream and
daemonClientStream in order to perform the tracking.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Add a virStreamPtr pointer to the _virNetClientStream
in order to reverse track the parent stream.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Use the return value of virObjectRef directly. This way, it's easier
for another reader to identify the reason why the additional reference
is required.
Signed-off-by: NMarc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: NBjoern Walk <bwalk@linux.vnet.ibm.com>

There are two functions on the client that handle incoming stream
data.  The first one virNetClientStreamQueuePacket() is a low
level function that just processes the incoming stream data from
the socket and stores it into an internal structure. This happens
in the client event loop therefore the shorter the callbacks are,
the better. The second function virNetClientStreamRecvPacket()
then handles copying data from internal structure into a client
provided buffer.
Change introduced in this commit makes just that: new queue for
incoming stream packets is introduced. Then instead of copying
data into intermediate internal buffer and then copying them into
user buffer, incoming stream messages are queue into the queue
and data is copied just once - in the upper layer function
virNetClientStreamRecvPacket(). In the end, there's just one
copying of data and therefore shorter event loop callback. This
should boost the performance which has proven to be the case in
my testing.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This reverts commit d9c9e138.

Unfortunately, things are going to be handled differently so this
commit must go.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

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

Use I/O vector (iovec) instead of one huge memory buffer as suggested
in https://bugzilla.redhat.com/show_bug.cgi?id=1026137#c7. This avoids
doing memmove() to big buffers and performance doesn't degrade if
source (virNetClientStreamQueuePacket()) is faster than sink
(virNetClientStreamRecvPacket()).

Resolves: http://bugzilla.redhat.com/1026137Signed-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>

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>

Since the event APIs are now in the public header, no internal
code should include virevent.h

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/

Make all the virNetClient* objects use virObject APIs for
reference counting
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

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

This rmoves all the per-file error reporting macros
from the code in src/rpc/
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The stream lock is unlocked twice instead of being locked and then
unlocked. Probably a typo.

If client stream does not have any data to sink and neither received
EOF, a dummy packet is sent to the daemon signalising client is ready to
sink some data. However, after we added event loop to client a race may
occur:

Thread 1 calls virNetClientStreamRecvPacket and since no data are cached
nor stream has EOF, it decides to send dummy packet to server which will
sent some data in turn. However, during this decision and actual message
exchange with server -

Thread 2 receives last stream data from server. Therefore an EOF is set
on stream and if there is a call waiting (which is not yet) it is woken
up. However, Thread 1 haven't sent anything so far, so there is no call
to be woken up. So this thread sent dummy packet to daemon, which
ignores that as no stream is associated with such packet and therefore
no reply will ever come.

This race causes client to hang indefinitely.

Stop multiplexing virNetClientSend for two different purposes,
instead add virNetClientSendWithReply and virNetClientSendNoReply

* src/rpc/virnetclient.c, src/rpc/virnetclient.h: Replace
  virNetClientSend with virNetClientSendWithReply and
  virNetClientSendNoReply
* src/rpc/virnetclientprogram.c, src/rpc/virnetclientstream.c:
  Update for new API names

If we receive an error on the stream, set the EOF marker so
that any further (bogus) incoming data is dropped.

* src/rpc/virnetclientstream.c: Set EOF on stream

commit 984840a2 removed the
notification of waiting calls when VIR_NET_CONTINUE messages
arrive. This was to fix the case of a virStreamAbort() call
being prematurely notified of completion.

The problem is that sometimes there are dummy calls from a
virStreamRecv() call waiting that *do* need to be notified.

These dummy calls should have a status VIR_NET_CONTINUE. So
re-add the notification upon VIR_NET_CONTINUE, but only if
the waiter also has a status of VIR_NET_CONTINUE.

* src/rpc/virnetclient.c: Notify waiting call if stream data
  arrives
* src/rpc/virnetclientstream.c:  Mark dummy stream read packet
  with status VIR_NET_CONTINUE

Commit 2c85644b attempted to
fix a problem with tracking RPC messages from streams by doing

-            if (msg->header.type == VIR_NET_REPLY) {
+            if (msg->header.type == VIR_NET_REPLY ||
+                (msg->header.type == VIR_NET_STREAM &&
+                 msg->header.status != VIR_NET_CONTINUE)) {
                 client->nrequests--;

In other words any stream packet, with status NET_OK or NET_ERROR
would cause nrequests to be decremented. This is great if the
packet from from a synchronous virStreamFinish or virStreamAbort
API call, but wildly wrong if from a server initiated abort.
The latter resulted in 'nrequests' being decremented below zero.
This then causes all I/O for that client to be stopped.

Instead of trying to infer whether we need to decrement the
nrequests field, from the message type/status, introduce an
explicit 'bool tracked' field to mark whether the virNetMessagePtr
object is subject to tracking.

Also add a virNetMessageClear function to allow a message
contents to be cleared out, without adversely impacting the
'tracked' field as a naive memset() would do

* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h: Add
  a 'bool tracked' field and virNetMessageClear() API
* daemon/remote.c, daemon/stream.c, src/rpc/virnetclientprogram.c,
  src/rpc/virnetclientstream.c, src/rpc/virnetserverclient.c,
  src/rpc/virnetserverprogram.c: Switch over to use
  virNetMessageClear() and pass in the 'bool tracked' value
  when creating messages.

In one exit path we forgot to free the virNetMessage object causing
a large memory leak for streams which send a lot of data. Some other
paths were calling VIR_FREE directly instead of virNetMessageFree
although this was (currently) harmless.

* src/rpc/virnetclientstream.c: Fix leak of msg object
* src/rpc/virnetclientprogram.c: Call virNetMessageFree instead
  of VIR_FREE

When the remote client receives end of file on the stream
it never invokes the stream callback. Applications relying
on async event driven I/O will thus never see the EOF
condition on the stream

* src/rpc/virnetclient.c, src/rpc/virnetclientstream.c:
  Ensure EOF is dispatched

The client stream object can be used independently of the
virNetClientPtr object, so must have full locking of its
own and not rely on any caller.

* src/remote/remote_driver.c: Remove locking around stream
  callback
* src/rpc/virnetclientstream.c: Add locking to all APIs
  and callbacks

* src/rpc/virnetclientstream.c: Avoid referencing NULL

To facilitate creation of new clients using XDR RPC services,
pull alot of the remote driver code into a set of reusable
objects.

 - virNetClient: Encapsulates a socket connection to a
   remote RPC server. Handles all the network I/O for
   reading/writing RPC messages. Delegates RPC encoding
   and decoding to the registered programs

 - virNetClientProgram: Handles processing and dispatch
   of RPC messages for a single RPC (program,version).
   A program can register to receive async events
   from a client

 - virNetClientStream: Handles generic I/O stream
   integration to RPC layer

Each new client program now merely needs to define the list of
RPC procedures & events it wants and their handlers. It does
not need to deal with any of the network I/O functionality at
all.