Enable migration without shared storage from the monitor

This patch adds the option to activate non-shared storage migration from the
monitor.
The migration command is as follows:
(qemu) migrate -d tcp:0:4444 # for ordinary live migration
(qemu) migrate -d -b tcp:0:4444 # for live migration with complete storage copy
(qemu) migrate -d -i tcp:0:4444 # for live migration with incremental storage copy, storage is cow based.

Changes from v4:
- Minor coding style issues.

Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/monitor.c b/monitor.c
index 132fb6e..3286ba2 100644
--- a/monitor.c
+++ b/monitor.c
@@ -2908,6 +2908,18 @@
 
 #define MAX_ARGS 16
 
+static int is_valid_option(const char *c, const char *typestr)
+{
+    char option[3];
+  
+    option[0] = '-';
+    option[1] = *c;
+    option[2] = '\0';
+  
+    typestr = strstr(typestr, option);
+    return (typestr != NULL);
+}
+
 static const mon_cmd_t *monitor_parse_command(Monitor *mon,
                                               const char *cmdline,
                                               QDict *qdict)
@@ -3100,7 +3112,8 @@
             break;
         case '-':
             {
-                int has_option;
+                const char *tmp = p;
+                int has_option, skip_key = 0;
                 /* option */
 
                 c = *typestr++;
@@ -3111,13 +3124,22 @@
                 has_option = 0;
                 if (*p == '-') {
                     p++;
-                    if (*p != c) {
-                        monitor_printf(mon, "%s: unsupported option -%c\n",
-                                       cmdname, *p);
-                        goto fail;
+                    if(c != *p) {
+                        if(!is_valid_option(p, typestr)) {
+                  
+                            monitor_printf(mon, "%s: unsupported option -%c\n",
+                                           cmdname, *p);
+                            goto fail;
+                        } else {
+                            skip_key = 1;
+                        }
                     }
-                    p++;
-                    has_option = 1;
+                    if(skip_key) {
+                        p = tmp;
+                    } else {
+                        p++;
+                        has_option = 1;
+                    }
                 }
                 qdict_put(qdict, key, qint_from_int(has_option));
             }