introduce -machine switch

diff --git a/hw/boards.h b/hw/boards.h
index 18b6b8f..bac8583 100644
--- a/hw/boards.h
+++ b/hw/boards.h
@@ -35,6 +35,10 @@  extern QEMUMachine *current_machine;
 
 #define COMMON_MACHINE_OPTS() 		\
     {                                   \
+        .name = "machine",              \
+        .type = QEMU_OPT_STRING,        \
+    },                                  \
+    {                                   \
         .name = "ram_size",             \
         .type = QEMU_OPT_NUMBER,        \
     },                                  \
diff --git a/hw/pc_piix.c b/hw/pc_piix.c
index f01194c..3ddb695 100644
--- a/hw/pc_piix.c
+++ b/hw/pc_piix.c
@@ -67,6 +67,9 @@  static void pc_init1(QemuOpts *opts, int pci_enabled)
 
     vmport_init();
 
+    if (!kernel_cmdline)
+        kernel_cmdline = "";
+
     /* allocate ram and load rom/bios */
     pc_memory_init(ram_size, kernel_filename, kernel_cmdline, initrd_filename,
                    &below_4g_mem_size, &above_4g_mem_size);
diff --git a/qemu-options.hx b/qemu-options.hx
index a6928b7..76ca866 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -35,6 +35,20 @@  STEXI
 Select the emulated @var{machine} (@code{-M ?} for list)
 ETEXI
 
+DEF("machine", HAS_ARG, QEMU_OPTION_machine,
+    "-machine [machine=m][,ram_size=ram][,boot_device=dev]\n"
+    "         [,kernel=vmlinux][,cmdline=kernel_cmdline][,initrd=initrd]\n"
+    "         [,cpu=cpu_type]\n"
+    "                pc-specific options: [,acpi=on|off]\n"
+    "                kvm-x86 specific options: [,apic_in_kernel=on|off]\n"
+    "                select emulated machine (-machine ? for list)\n",
+    QEMU_ARCH_ALL)
+STEXI
+@item -machine @var{machine}[,@var{option}]
+@findex -machine
+Select the emulated @var{machine} (@code{-machine ?} for list)
+ETEXI
+
 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
     "-cpu cpu        select CPU (-cpu ? for list)\n", QEMU_ARCH_ALL)
 STEXI
diff --git a/vl.c b/vl.c
index 96b8d35..177ffe2 100644
--- a/vl.c
+++ b/vl.c
@@ -1605,6 +1605,16 @@  static QEMUMachine *find_machine(const char *name)
         if (m->alias && !strcmp(m->alias, name))
             return m;
     }
+
+    printf("Supported machines are:\n");
+    for(m = first_machine; m != NULL; m = m->next) {
+	if (m->alias)
+	    printf("%-10s %s (alias of %s)\n",
+		   m->alias, m->desc, m->name);
+	printf("%-10s %s%s\n",
+	       m->name, m->desc,
+	       m->is_default ? " (default)" : "");
+    }
     return NULL;
 }
 
@@ -2567,7 +2577,7 @@  int main(int argc, char **argv, char **envp)
     DisplayState *ds;
     DisplayChangeListener *dcl;
     int cyls, heads, secs, translation;
-    QemuOpts *hda_opts = NULL, *opts;
+    QemuOpts *hda_opts = NULL, *machine_opts = NULL, *opts = NULL;
     int optind;
     const char *optarg;
     const char *loadvm = NULL;
@@ -2697,21 +2707,29 @@  int main(int argc, char **argv, char **envp)
                 exit(1);
             }
             switch(popt->index) {
+            case QEMU_OPTION_machine: {
+		const char *mach;
+
+                machine_opts = qemu_opts_parse(&qemu_machine_opts, optarg, 0);
+                if (!machine_opts) {
+                    fprintf(stderr, "parse error: %s\n", optarg);
+                    exit(1);
+                }
+                mach = qemu_opt_get(machine_opts, "machine");
+
+		if (!mach)
+			break;
+
+                machine = find_machine(mach);
+
+                if (!machine)
+                    exit(*mach != '?');
+		break;
+	    }
             case QEMU_OPTION_M:
                 machine = find_machine(optarg);
-                if (!machine) {
-                    QEMUMachine *m;
-                    printf("Supported machines are:\n");
-                    for(m = first_machine; m != NULL; m = m->next) {
-                        if (m->alias)
-                            printf("%-10s %s (alias of %s)\n",
-                                   m->alias, m->desc, m->name);
-                        printf("%-10s %s%s\n",
-                               m->name, m->desc,
-                               m->is_default ? " (default)" : "");
-                    }
-                    exit(*optarg != '?');
-                }
+                if (!machine) 
+                       exit(*optarg != '?');
                 break;
             case QEMU_OPTION_cpu:
                 /* hw initialization will check this */
@@ -3723,47 +3741,49 @@  int main(int argc, char **argv, char **envp)
     }
     qemu_add_globals();
 
-    opts = qemu_opts_create(&qemu_machine_opts, NULL, 0);
+    if (!machine_opts)
+        machine_opts = qemu_opts_create(&qemu_machine_opts, NULL, 0);
+
     if (kernel_filename) {
-        qemu_opt_set(opts, "kernel", kernel_filename);
+        qemu_opt_set(machine_opts, "kernel", kernel_filename);
         if (kernel_cmdline) {
-            qemu_opt_set(opts, "cmdline", kernel_cmdline);
+            qemu_opt_set(machine_opts, "cmdline", kernel_cmdline);
         }
         if (initrd_filename) {
-            qemu_opt_set(opts, "initrd", initrd_filename);
+            qemu_opt_set(machine_opts, "initrd", initrd_filename);
         }
     }
 
-    qemu_opt_set(opts, "boot_device", boot_devices);
+    qemu_opt_set(machine_opts, "boot_device", boot_devices);
 
     if (cpu_model) {
-        qemu_opt_set(opts, "cpu", cpu_model);
+        qemu_opt_set(machine_opts, "cpu", cpu_model);
     }
 
     if (ram_size) {
         char buffer[64];
         snprintf(buffer, sizeof(buffer),
                  "%" PRId64, ram_size);
-        qemu_opt_set(opts, "ram_size", buffer);
+        qemu_opt_set(machine_opts, "ram_size", buffer);
     }
 
     if (acpi_enabled == 0) {
-        qemu_opt_set(opts, "acpi", "off");
+        qemu_opt_set(machine_opts, "acpi", "off");
     }
 
     if (machine->opts_desc) {
-        if (qemu_opts_validate(opts, machine->opts_desc) < 0) {
+        if (qemu_opts_validate(machine_opts, machine->opts_desc) < 0) {
             exit(1);
         }
     } else {
-        if (qemu_opts_validate(opts, common_machine_opts) < 0) {
+        if (qemu_opts_validate(machine_opts, common_machine_opts) < 0) {
             exit(1);
         }
     }
     
-    machine->init(machine, opts);
+    machine->init(machine, machine_opts);
 
-    qemu_opts_del(opts);
+    qemu_opts_del(machine_opts);
 
     cpu_synchronize_all_post_init();