The virtlogd RPC messages all have a flags parameter. For
sake of future error reporting we should be verifying
these are all 0 for now.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The current virtlogd RPC protocol provides the ability to
handle log files associated with QEMU stdout/err. The log
protocol messages take the virt driver, domain name and
use that to form a log file path. This is quite restrictive
as it prevents us re-using the same RPC protocol messages
for logging to char device backends where the filename
can be arbitrarily user specified. It is also bad because
it means we have 2 separate locations which have to decide
on logfile name.

This change alters the RPC protocol so that we pass the
desired log file path along when opening the log file
initially. Now the virt driver is exclusively in charge
of deciding the log filename
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virt driver, dom name and uuid associated with a log
file are important pieces of metadata to keep around for
sake of future enhancements to virtlogd. Currently we
discard them after opening the log file, but we should
preserve them, even across restarts.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The problem is that in some mingw header DATADIR is used but
gnulib defines it too. This leads to the following compile error:

  CC       locking/libvirt_driver_la-lock_manager.lo
In file included from /usr/i686-w64-mingw32/sys-root/mingw/include/objbase.h:66:0,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/ole2.h:17,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/wtypes.h:12,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/winscard.h:10,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/windows.h:97,
                 from /usr/i686-w64-mingw32/sys-root/mingw/include/winsock2.h:23,
                 from ../gnulib/lib/unistd.h:48,
                 from ../../src/util/virutil.h:29,
                 from ../../src/logging/log_manager.c:30:
/usr/i686-w64-mingw32/sys-root/mingw/include/objidl.h:12275:2: error: expected identifier or '(' before string constant
 } DATADIR;
  ^
Makefile:7888: recipe for target 'logging/libvirt_driver_la-log_manager.lo' failed

The fix is to include configmake.h at the end of includes.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

With some versions of GLibC / GCC, a variable called 'daemon'
will result in a warning about clashing with the function also
named 'daemon'. Rename it to 'dmn' to avoid the clash.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Otherwise we fail on 32bit with:

CC     logging/virtlogd-log_daemon_dispatch.o
logging/log_daemon_dispatch.c: In function 'virLogManagerProtocolDispatchDomainReadLogFile':
logging/log_daemon_dispatch.c:120:9: error: format '%zu' expects argument of type 'size_t', but argument 7 has type 'uint64_t' [-Werror=format]

The virtlogd daemon is launched with a 30 second timeout for
unprivileged users. Unfortunately the timeout is only inhibited
while RPC clients are connected, and they only connect for a
short while to open the log file descriptor. We need to hold
an inhibition for as long as the log file descriptor itself
is open.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Add the virLogManager API which allows for communication with
the virtlogd daemon to RPC program. This provides the client
side API to open log files for guest domains.

The virtlogd daemon is setup to auto-spawn on first use when
running unprivileged. For privileged usage, systemd socket
activation is used instead.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Define a new RPC protocol for the virtlogd daemon that provides
for handling of logs. The initial RPC method defined allows a
client to obtain a file handle to use for writing to a log
file for a guest domain. The file handle passed back will not
actually refer to the log file, but rather an anonymous pipe.
The virtlogd daemon will forward I/O between them, ensuring
file rotation happens when required.

Initially the log setup is hardcoded to cap log files at
128 KB, and keep 3 backups when rolling over, which gives
a max usage of 512 KB per guest.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Copy the virtlockd codebase across to form the initial virlogd
code. Simple search & replace of s/lock/log/ and gut the remote
protocol & dispatcher. This gives us a daemon that starts up
and listens for connections, but does nothing with them.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>