Re: [Qemu-devel] [PATCH 1/2] qdev-properties: add UUID property type

[Corey Minyard]

On 11/24/2017 09:36 AM, Roman Kagan wrote:

UUIDs (GUIDs) are widely used in VMBus-related stuff, so a dedicated
property type becomes helpful.

Signed-off-by: Roman Kagan <rka...@virtuozzo.com>
---
  include/hw/qdev-properties.h |  3 +++
  hw/core/qdev-properties.c    | 52 ++++++++++++++++++++++++++++++++++++++++++++
  2 files changed, 55 insertions(+)

diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index e2321f1cc1..d4da7dd1f1 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -30,6 +30,7 @@ extern const PropertyInfo qdev_prop_vlan;
  extern const PropertyInfo qdev_prop_pci_devfn;
  extern const PropertyInfo qdev_prop_blocksize;
  extern const PropertyInfo qdev_prop_pci_host_devaddr;
+extern const PropertyInfo qdev_prop_uuid;
  extern const PropertyInfo qdev_prop_arraylen;
  extern const PropertyInfo qdev_prop_link;

@@ -212,6 +213,8 @@ extern const PropertyInfo qdev_prop_link;

      DEFINE_PROP(_n, _s, _f, qdev_prop_pci_host_devaddr, PCIHostDeviceAddress)
  #define DEFINE_PROP_MEMORY_REGION(_n, _s, _f)             \
      DEFINE_PROP(_n, _s, _f, qdev_prop_ptr, MemoryRegion *)
+#define DEFINE_PROP_UUID(_n, _s, _f) \
+    DEFINE_PROP(_n, _s, _f, qdev_prop_uuid, QemuUUID)

#define DEFINE_PROP_END_OF_LIST() \

      {}
diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index 1dc80fcea2..49fea5a40a 100644
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -10,6 +10,7 @@
  #include "net/hub.h"
  #include "qapi/visitor.h"
  #include "chardev/char.h"
+#include "qemu/uuid.h"

void qdev_prop_set_after_realize(DeviceState *dev, const char *name,

                                    Error **errp)
@@ -883,6 +884,57 @@ const PropertyInfo qdev_prop_pci_host_devaddr = {
      .set = set_pci_host_devaddr,
  };

+/* --- UUID --- */

+
+static void get_uuid(Object *obj, Visitor *v, const char *name, void *opaque,
+                     Error **errp)
+{
+    DeviceState *dev = DEVICE(obj);
+    Property *prop = opaque;
+    QemuUUID *uuid = qdev_get_prop_ptr(dev, prop);
+    char buffer[UUID_FMT_LEN + 1];
+    char *p = buffer;
+
+    qemu_uuid_unparse(uuid, buffer);
+
+    visit_type_str(v, name, &p, errp);
+}
+
+static void set_uuid(Object *obj, Visitor *v, const char *name, void *opaque,
+                    Error **errp)
+{
+    DeviceState *dev = DEVICE(obj);
+    Property *prop = opaque;
+    QemuUUID *uuid = qdev_get_prop_ptr(dev, prop);
+    Error *local_err = NULL;
+    char *str;
+
+    if (dev->realized) {
+        qdev_prop_set_after_realize(dev, name, errp);
+        return;
+    }
+
+    visit_type_str(v, name, &str, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
+
+    if (!strcmp(str, "auto")) {
+        qemu_uuid_generate(uuid);
+    } else if (qemu_uuid_parse(str, uuid) < 0) {
+        error_set_from_qdev_prop_error(errp, EINVAL, dev, prop, str);
+    }
+    g_free(str);
+}
+
+const PropertyInfo qdev_prop_uuid = {
+    .name  = "str",
+    .description = "UUID (aka GUID) or \"auto\" for random value",
+    .get   = get_uuid,
+    .set   = set_uuid,

There is a UUID value you can use as a default in  vl.c, named qemu_uuid.
Just in case you want to set a default value here.

-corey

+};
+
  /* --- support for array properties --- */

/* Used as an opaque for the object properties we add for each