[Qemu-devel] [PULL 06/38] Generalize QOM publishing of date and time from mc146818rtc.c

[Alexander Graf <agraf@suse.de>]

From: David Gibson <david@gibson.dropbear.id.au>

The mc146818rtc driver exposes the current RTC date and time via the "date"
property in QOM (which is also aliased to the machine's "rtc-time"
property).  Currently it uses a custom visitor function rtc_get_date to
do this.

This patch introduces new helpers to the QOM core to expose struct tm
valued properties via a getter function, so that this functionality can be
more easily duplicated in other RTC implementations.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
---
 hw/timer/mc146818rtc.c | 44 ++--------------------------
 include/qom/object.h   | 14 +++++++++
 qom/object.c           | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 96 insertions(+), 41 deletions(-)

diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c
index 0600c9a..f2b77fa 100644
--- a/hw/timer/mc146818rtc.c
+++ b/hw/timer/mc146818rtc.c
@@ -831,49 +831,12 @@ static const MemoryRegionOps cmos_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
 };
 
-static void rtc_get_date(Object *obj, Visitor *v, void *opaque,
-                         const char *name, Error **errp)
+static void rtc_get_date(Object *obj, struct tm *current_tm, Error **errp)
 {
-    Error *err = NULL;
     RTCState *s = MC146818_RTC(obj);
-    struct tm current_tm;
 
     rtc_update_time(s);
-    rtc_get_time(s, &current_tm);
-    visit_start_struct(v, NULL, "struct tm", name, 0, &err);
-    if (err) {
-        goto out;
-    }
-    visit_type_int32(v, &current_tm.tm_year, "tm_year", &err);
-    if (err) {
-        goto out_end;
-    }
-    visit_type_int32(v, &current_tm.tm_mon, "tm_mon", &err);
-    if (err) {
-        goto out_end;
-    }
-    visit_type_int32(v, &current_tm.tm_mday, "tm_mday", &err);
-    if (err) {
-        goto out_end;
-    }
-    visit_type_int32(v, &current_tm.tm_hour, "tm_hour", &err);
-    if (err) {
-        goto out_end;
-    }
-    visit_type_int32(v, &current_tm.tm_min, "tm_min", &err);
-    if (err) {
-        goto out_end;
-    }
-    visit_type_int32(v, &current_tm.tm_sec, "tm_sec", &err);
-    if (err) {
-        goto out_end;
-    }
-out_end:
-    error_propagate(errp, err);
-    err = NULL;
-    visit_end_struct(v, errp);
-out:
-    error_propagate(errp, err);
+    rtc_get_time(s, current_tm);
 }
 
 static void rtc_realizefn(DeviceState *dev, Error **errp)
@@ -932,8 +895,7 @@ static void rtc_realizefn(DeviceState *dev, Error **errp)
     qdev_set_legacy_instance_id(dev, base, 3);
     qemu_register_reset(rtc_reset, s);
 
-    object_property_add(OBJECT(s), "date", "struct tm",
-                        rtc_get_date, NULL, NULL, s, NULL);
+    object_property_add_tm(OBJECT(s), "date", rtc_get_date, NULL);
 
     object_property_add_alias(qdev_get_machine(), "rtc-time",
                               OBJECT(s), "date", NULL);
diff --git a/include/qom/object.h b/include/qom/object.h
index 8757573..d2d7748 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -1204,6 +1204,20 @@ void object_property_add_bool(Object *obj, const char *name,
                               Error **errp);
 
 /**
+ * object_property_add_tm:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @get: the getter or NULL if the property is write-only.
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add a read-only struct tm valued property using a getter function.
+ * This function will add a property of type 'struct tm'.
+ */
+void object_property_add_tm(Object *obj, const char *name,
+                            void (*get)(Object *, struct tm *, Error **),
+                            Error **errp);
+
+/**
  * object_property_add_uint8_ptr:
  * @obj: the object to add a property to
  * @name: the name of the property
diff --git a/qom/object.c b/qom/object.c
index 1812c73..d167038 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1543,6 +1543,85 @@ void object_property_add_bool(Object *obj, const char *name,
     }
 }
 
+typedef struct TMProperty {
+    void (*get)(Object *, struct tm *, Error **);
+} TMProperty;
+
+static void property_get_tm(Object *obj, Visitor *v, void *opaque,
+                            const char *name, Error **errp)
+{
+    TMProperty *prop = opaque;
+    Error *err = NULL;
+    struct tm value;
+
+    prop->get(obj, &value, &err);
+    if (err) {
+        goto out;
+    }
+
+    visit_start_struct(v, NULL, "struct tm", name, 0, &err);
+    if (err) {
+        goto out;
+    }
+    visit_type_int32(v, &value.tm_year, "tm_year", &err);
+    if (err) {
+        goto out_end;
+    }
+    visit_type_int32(v, &value.tm_mon, "tm_mon", &err);
+    if (err) {
+        goto out_end;
+    }
+    visit_type_int32(v, &value.tm_mday, "tm_mday", &err);
+    if (err) {
+        goto out_end;
+    }
+    visit_type_int32(v, &value.tm_hour, "tm_hour", &err);
+    if (err) {
+        goto out_end;
+    }
+    visit_type_int32(v, &value.tm_min, "tm_min", &err);
+    if (err) {
+        goto out_end;
+    }
+    visit_type_int32(v, &value.tm_sec, "tm_sec", &err);
+    if (err) {
+        goto out_end;
+    }
+out_end:
+    error_propagate(errp, err);
+    err = NULL;
+    visit_end_struct(v, errp);
+out:
+    error_propagate(errp, err);
+
+}
+
+static void property_release_tm(Object *obj, const char *name,
+                                void *opaque)
+{
+    TMProperty *prop = opaque;
+    g_free(prop);
+}
+
+void object_property_add_tm(Object *obj, const char *name,
+                            void (*get)(Object *, struct tm *, Error **),
+                            Error **errp)
+{
+    Error *local_err = NULL;
+    TMProperty *prop = g_malloc0(sizeof(*prop));
+
+    prop->get = get;
+
+    object_property_add(obj, name, "struct tm",
+                        get ? property_get_tm : NULL, NULL,
+                        property_release_tm,
+                        prop, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        g_free(prop);
+    }
+}
+
 static char *qdev_get_type(Object *obj, Error **errp)
 {
     return g_strdup(object_get_typename(obj));
-- 
1.8.1.4