[Qemu-devel] [PATCH 1/3] qdev: add print_options callback

[Alon Levy <alevy@redhat.com>]

another callback added to PropertyInfo, for later use by PROP_TYPE_ENUM.
Allows printing of runtime computed options when doing:
 qemu -device foo,?
---
 hw/qdev.c |   10 +++++++++-
 hw/qdev.h |    1 +
 2 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/hw/qdev.c b/hw/qdev.c
index 5b8d374..d1550b9 100644
--- a/hw/qdev.c
+++ b/hw/qdev.c
@@ -188,7 +188,15 @@ int qdev_device_help(QemuOpts *opts)
         if (!prop->info->parse) {
             continue;           /* no way to set it, don't show */
         }
-        error_printf("%s.%s=%s\n", info->name, prop->name, prop->info->name);
+        if (prop->info->print_options) {
+            char buf[256];
+            int ret;
+            ret = prop->info->print_options(info, prop, buf, sizeof(buf) - 3);
+            error_printf("%s.%s=%s%s\n", info->name, prop->name, buf,
+                ret == sizeof(buf) - 3 ? "..." : "" );
+        } else {
+            error_printf("%s.%s=%s\n", info->name, prop->name, prop->info->name);
+        }
     }
     return 1;
 }
diff --git a/hw/qdev.h b/hw/qdev.h
index e520aaa..530fc5d 100644
--- a/hw/qdev.h
+++ b/hw/qdev.h
@@ -109,6 +109,7 @@ struct PropertyInfo {
     enum PropertyType type;
     int (*parse)(DeviceState *dev, Property *prop, const char *str);
     int (*print)(DeviceState *dev, Property *prop, char *dest, size_t len);
+    int (*print_options)(DeviceInfo *info, Property *prop, char *dest, size_t len);
     void (*free)(DeviceState *dev, Property *prop);
 };
 
-- 
1.7.3.4