monitor: Introduce MONITOR_USE_CONTROL flag

This flag will be set when Monitor enters "control mode", in
which the output will be defined by the QEMU Monitor Protocol.

This also introduces a macro to check if the flag is set.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

monitor.c

@@ -119,6 +119,12 @@ Monitor *cur_mon = NULL;
 static void monitor_command_cb(Monitor *mon, const char *cmdline,
                                void *opaque);
 
+/* Return true if in control mode, false otherwise */
+static inline int monitor_ctrl_mode(const Monitor *mon)
+{
+    return (mon->flags & MONITOR_USE_CONTROL);
+}
+
 static void monitor_read_command(Monitor *mon, int show_prompt)
 {
     readline_start(mon->rs, "(qemu) ", 0, monitor_command_cb, NULL);

monitor.h

@@ -11,6 +11,7 @@ extern Monitor *cur_mon;
 /* flags for monitor_init */
 #define MONITOR_IS_DEFAULT    0x01
 #define MONITOR_USE_READLINE  0x02
+#define MONITOR_USE_CONTROL   0x04
 
 void monitor_init(CharDriverState *chr, int flags);