[Qemu-devel] [RFC PATCH 1/6] machine: add a deprecated_reason property

[Philippe Mathieu-Daudé]

If a machine has the deprecated_reason property set:
- it won't get listed anymore by the "-M help" command,
- a warning will be displayed if the machine is used.

Example:
  $ ppc-softmmu/qemu-system-ppc -M prep
  qemu-system-ppc: -M prep: warning: The PowerPC PREP platform machine is 
deprecated (Obsoleted by the "40p" machine)
  [machine starting ...]

Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
---
 include/hw/boards.h | 1 +
 vl.c                | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 191a5b3cd8..4d5c180968 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -182,6 +182,7 @@ struct MachineClass {
     const char *default_boot_order;
     const char *default_display;
     GArray *compat_props;
+    const char *deprecated_reason;
     const char *hw_version;
     ram_addr_t default_ram_size;
     const char *default_cpu_type;
diff --git a/vl.c b/vl.c
index ec299099ff..9ed4648af2 100644
--- a/vl.c
+++ b/vl.c
@@ -2742,6 +2742,10 @@ static gint machine_class_cmp(gconstpointer a, 
gconstpointer b)
     }
     if (mc) {
         g_slist_free(machines);
+        if (mc->deprecated_reason) {
+            warn_report("The %s machine is deprecated (%s)",
+                        mc->desc, mc->deprecated_reason);
+        }
         return mc;
     }
     if (name && !is_help_option(name)) {
@@ -2752,6 +2756,9 @@ static gint machine_class_cmp(gconstpointer a, 
gconstpointer b)
         machines = g_slist_sort(machines, machine_class_cmp);
         for (el = machines; el; el = el->next) {
             MachineClass *mc = el->data;
+            if (mc->deprecated_reason) {
+                continue;
+            }
             if (mc->alias) {
                 printf("%-20s %s (alias of %s)\n", mc->alias, mc->desc, 
mc->name);
             }
-- 
2.15.0