monitor: Command-line flag to enable control mode

This commit adds a flag called 'control' to the '-monitor'
command-line option. This flag enables control mode.

The syntax is:

qemu [...] -monitor control,<device>

Where <device> is a chardev (excluding 'vc', for obvious reasons).

For example:

$ qemu [...] -monitor control,tcp:localhost:4444,server

Will run QEMU in control mode, waiting for a client TCP connection
on localhost port 4444.

NOTE: I've tried using QemuOpts for this, but turns out that it
will try to parse the device part, which should be untouched.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/qemu-options.hx b/qemu-options.hx
index b65fd74f32..1b5781a10b 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1577,13 +1577,14 @@ Use @code{-parallel none} to disable all parallel ports.
 ETEXI
 
 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
-    "-monitor dev    redirect the monitor to char device 'dev'\n")
+    "-monitor [control,]dev    redirect the monitor to char device 'dev'\n")
 STEXI
-@item -monitor @var{dev}
+@item -monitor [@var{control},]@var{dev}
 Redirect the monitor to host device @var{dev} (same devices as the
 serial port).
 The default device is @code{vc} in graphical mode and @code{stdio} in
 non graphical mode.
+The option @var{control} enables the QEMU Monitor Protocol.
 ETEXI
 
 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \