util: json: Add helper to return string or number properties as string

The helper is useful in cases when the JSON we have to parse may contain
one of the two due to historical reasons and the number value itself
would be stored as a string.

src/util/virjson.c

@@ -1208,6 +1208,33 @@ virJSONValueObjectGetString(virJSONValuePtr object,
 }
 
 
+/**
+ * virJSONValueObjectGetStringOrNumber:
+ * @object: JSON value object
+ * @key: name of the property in @object to get
+ *
+ * Gets a property named @key from the JSON object @object. The value may be
+ * a number or a string and is returned as a string. In cases when the property
+ * is not present or is not a string or number NULL is returned.
+ */
+const char *
+virJSONValueObjectGetStringOrNumber(virJSONValuePtr object,
+                                    const char *key)
+{
+    virJSONValuePtr val = virJSONValueObjectGet(object, key);
+
+    if (!val)
+        return NULL;
+
+    if (val->type == VIR_JSON_TYPE_STRING)
+        return val->data.string;
+    else if (val->type == VIR_JSON_TYPE_NUMBER)
+        return val->data.number;
+
+    return NULL;
+}
+
+
 int
 virJSONValueObjectGetNumberInt(virJSONValuePtr object,
                                const char *key,

src/util/virjson.h

@@ -149,6 +149,7 @@ virJSONValuePtr virJSONValueObjectStealArray(virJSONValuePtr object,
                                              const char *key);
 
 const char *virJSONValueObjectGetString(virJSONValuePtr object, const char *key);
+const char *virJSONValueObjectGetStringOrNumber(virJSONValuePtr object, const char *key);
 int virJSONValueObjectGetNumberInt(virJSONValuePtr object, const char *key, int *value);
 int virJSONValueObjectGetNumberUint(virJSONValuePtr object, const char *key, unsigned int *value);
 int virJSONValueObjectGetNumberLong(virJSONValuePtr object, const char *key, long long *value);