[Qemu-devel] [PATCH RFC V2 2/9] vl: use qemu machine QOM class instead of global machines list

[Marcel Apfelbaum <marcel.a@redhat.com>]

The machine registration flow is refactored to use the QOM functionality.
Instead of linking the machines into a list, each machine has a type
and the types can be traversed in the QOM way.

Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
---
 include/hw/boards.h |  1 +
 vl.c                | 75 ++++++++++++++++++++++++++++++++++++++---------------
 2 files changed, 55 insertions(+), 21 deletions(-)

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 7b4708d..65e1e03 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -49,6 +49,7 @@ struct QEMUMachine {
     const char *hw_version;
 };
 
+#define TYPE_QEMU_MACHINE_PREFIX "machine-"
 int qemu_register_machine(QEMUMachine *m);
 QEMUMachine *find_default_machine(void);
 
diff --git a/vl.c b/vl.c
index 9379d33..50c880f 100644
--- a/vl.c
+++ b/vl.c
@@ -1529,54 +1529,81 @@ void pcmcia_info(Monitor *mon, const QDict *qdict)
 /***********************************************************/
 /* machine registration */
 
-static QEMUMachine *first_machine = NULL;
 QEMUMachine *current_machine = NULL;
 
+static void qemu_machine_class_init(ObjectClass *klass, void *data)
+{
+    QemuMachineClass *k = QEMU_MACHINE_CLASS(klass);
+
+    k->qemu_machine = data;
+}
+
 int qemu_register_machine(QEMUMachine *m)
 {
-    QEMUMachine **pm;
-    pm = &first_machine;
-    while (*pm != NULL)
-        pm = &(*pm)->next;
-    m->next = NULL;
-    *pm = m;
+    TypeInfo ti = {
+        .name       = g_strconcat(TYPE_QEMU_MACHINE_PREFIX, m->name, NULL),
+        .parent     = TYPE_QEMU_MACHINE,
+        .class_init = qemu_machine_class_init,
+        .class_data = (void *)m,
+    };
+
+    type_register(&ti);
+
     return 0;
 }
 
 static QEMUMachine *find_machine(const char *name)
 {
-    QEMUMachine *m;
+    GSList *el, *machines = object_class_get_list(TYPE_QEMU_MACHINE, false);
+    QEMUMachine *m = NULL;
+
+    for (el = machines; el; el = el->next) {
+        QemuMachineClass *k = el->data;
 
-    for(m = first_machine; m != NULL; m = m->next) {
-        if (!strcmp(m->name, name))
-            return m;
-        if (m->alias && !strcmp(m->alias, name))
-            return m;
+        if (!strcmp(k->qemu_machine->name, name)) {
+            m = k->qemu_machine;
+            break;
+        }
+        if (k->qemu_machine->alias && !strcmp(k->qemu_machine->alias, name)) {
+            m = k->qemu_machine;
+            break;
+        }
     }
-    return NULL;
+
+    g_slist_free(machines);
+    return m;
 }
 
 QEMUMachine *find_default_machine(void)
 {
-    QEMUMachine *m;
+    GSList *el, *machines = object_class_get_list(TYPE_QEMU_MACHINE, false);
+    QEMUMachine *m = NULL;
 
-    for(m = first_machine; m != NULL; m = m->next) {
-        if (m->is_default) {
-            return m;
+    for (el = machines; el; el = el->next) {
+        QemuMachineClass *k = el->data;
+
+        if (k->qemu_machine->is_default) {
+            m = k->qemu_machine;
+            break;
         }
     }
-    return NULL;
+
+    g_slist_free(machines);
+    return m;
 }
 
 MachineInfoList *qmp_query_machines(Error **errp)
 {
+    GSList *el, *machines = object_class_get_list(TYPE_QEMU_MACHINE, false);
     MachineInfoList *mach_list = NULL;
     QEMUMachine *m;
 
-    for (m = first_machine; m; m = m->next) {
+    for (el = machines; el; el = el->next) {
+        QemuMachineClass *k = el->data;
         MachineInfoList *entry;
         MachineInfo *info;
 
+        m = k->qemu_machine;
         info = g_malloc0(sizeof(*info));
         if (m->is_default) {
             info->has_is_default = true;
@@ -1597,6 +1624,7 @@ MachineInfoList *qmp_query_machines(Error **errp)
         mach_list = entry;
     }
 
+    g_slist_free(machines);
     return mach_list;
 }
 
@@ -2540,6 +2568,7 @@ static int debugcon_parse(const char *devname)
 static QEMUMachine *machine_parse(const char *name)
 {
     QEMUMachine *m, *machine = NULL;
+    GSList *el, *machines = object_class_get_list(TYPE_QEMU_MACHINE, false);
 
     if (name) {
         machine = find_machine(name);
@@ -2548,13 +2577,17 @@ static QEMUMachine *machine_parse(const char *name)
         return machine;
     }
     printf("Supported machines are:\n");
-    for (m = first_machine; m != NULL; m = m->next) {
+    for (el = machines; el; el = el->next) {
+        QemuMachineClass *k = el->data;
+        m = k->qemu_machine;
         if (m->alias) {
             printf("%-20s %s (alias of %s)\n", m->alias, m->desc, m->name);
         }
         printf("%-20s %s%s\n", m->name, m->desc,
                m->is_default ? " (default)" : "");
     }
+
+    g_slist_free(machines);
     exit(!name || !is_help_option(name));
 }
 
-- 
1.8.3.1