>From 43fb56c4ee68905d886ea21dad338f3e76350ba5 Mon Sep 17 00:00:00 2001
From: Anthony Liguori <address@hidden>
Date: Tue, 22 Mar 2011 08:21:00 -0500
Subject: [PATCH] vl: add -dump-savevm option to display VMState schema

This can be used to verify whether the savevm schema has changed for a given
version of the migration protocol.

Signed-off-by: Anthony Liguori <address@hidden>
---
 hw/hw.h         |    2 ++
 qemu-options.hx |    9 +++++++++
 savevm.c        |   22 ++++++++++++++++++++++
 vl.c            |    9 +++++++++
 4 files changed, 42 insertions(+), 0 deletions(-)

diff --git a/hw/hw.h b/hw/hw.h
index 1b09039..55816da 100644
--- a/hw/hw.h
+++ b/hw/hw.h
@@ -914,4 +914,6 @@ int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
                                    int required_for_version);
 void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
                         void *opaque);
+void vmstate_dump(FILE *f, int version);
+
 #endif
diff --git a/qemu-options.hx b/qemu-options.hx
index badb730..801757b 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2349,6 +2349,15 @@ Specify a trace file to log output traces to.
 ETEXI
 #endif
 
+DEF("dump-savevm", HAS_ARG, QEMU_OPTION_dump_savevm,
+    "-dump-savevm VERSION\n"
+    "                dump the savevm schema for a given version\n",
+    QEMU_ARCH_ALL)
+STEXI
address@hidden -dump-savevm
address@hidden -dump-savevm
+ETEXI
+
 HXCOMM This is the last statement. Insert new options before this line!
 STEXI
 @end table
diff --git a/savevm.c b/savevm.c
index 03fce62..da1fea1 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1436,6 +1436,28 @@ static void vmstate_save(QEMUFile *f, SaveStateEntry *se)
     vmstate_save_state(f,se->vmsd, se->opaque);
 }
 
+void vmstate_dump(FILE *f, int version)
+{
+    SaveStateEntry *se;
+    bool first = true;
+
+    QTAILQ_FOREACH(se, &savevm_handlers, entry) {
+        VMStateField *field;
+        if (!se->vmsd) {
+            continue;
+        }
+        if (first) {
+            first = false;
+        } else {
+            fprintf(f, "\n");
+        }
+        fprintf(f, "%s.__version__ = %d\n", se->vmsd->name, se->version_id);
+        for (field = se->vmsd->fields; field->name; field++) {
+            fprintf(f, "%s.%s\n", se->vmsd->name, field->name);
+        }
+    }
+}
+
 #define QEMU_VM_FILE_MAGIC           0x5145564d
 #define QEMU_VM_FILE_VERSION_COMPAT  0x00000002
 #define QEMU_VM_FILE_VERSION         0x00000003
diff --git a/vl.c b/vl.c
index ac47211..361fcef 100644
--- a/vl.c
+++ b/vl.c
@@ -1941,6 +1941,7 @@ int main(int argc, char **argv, char **envp)
     int show_vnc_port = 0;
     int defconfig = 1;
     const char *trace_file = NULL;
+    int dump_savevm = -1;
 
     atexit(qemu_run_exit_notifiers);
     error_set_progname(argv[0]);
@@ -2760,6 +2761,9 @@ int main(int argc, char **argv, char **envp)
                     fclose(fp);
                     break;
                 }
+            case QEMU_OPTION_dump_savevm:
+                dump_savevm = atoi(optarg);
+                break;
             default:
                 os_parse_cmd_args(popt->index, optarg);
             }
@@ -3013,6 +3017,11 @@ int main(int argc, char **argv, char **envp)
 
     cpu_synchronize_all_post_init();
 
+    if (dump_savevm != -1) {
+        vmstate_dump(stdout, dump_savevm);
+        exit(0);
+    }
+
     /* must be after terminal init, SDL library changes signal handlers */
     os_setup_signal_handling();
 
-- 
1.7.0.4