Error: Introduce error_copy()

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

error.c

@@ -43,6 +43,19 @@ void error_set(Error **errp, const char *fmt, ...)
     *errp = err;
 }
 
+Error *error_copy(const Error *err)
+{
+    Error *err_new;
+
+    err_new = g_malloc0(sizeof(*err));
+    err_new->msg = g_strdup(err->msg);
+    err_new->fmt = err->fmt;
+    err_new->obj = err->obj;
+    QINCREF(err_new->obj);
+
+    return err_new;
+}
+
 bool error_is_set(Error **errp)
 {
     return (errp && *errp);

error.h

@@ -34,6 +34,11 @@ void error_set(Error **err, const char *fmt, ...) GCC_FMT_ATTR(2, 3);
  */
 bool error_is_set(Error **err);
 
+/**
+ * Returns an exact copy of the error passed as an argument.
+ */
+Error *error_copy(const Error *err);
+
 /**
  * Get a human readable representation of an error object.
  */