qom: simplify object_find_property / object_class_find_property

When debugging QEMU it is often useful to put a breakpoint on the
error_setg_internal method impl.

Unfortunately the object_property_add / object_class_property_add
methods call object_property_find / object_class_property_find methods
to check if a property exists already before adding the new property.

As a result there are a huge number of calls to error_setg_internal
on startup of most QEMU commands, making it very painful to set a
breakpoint on this method.

Most callers of object_find_property and object_class_find_property,
however, pass in a NULL for the Error parameter. This simplifies the
methods to remove the Error parameter entirely, and then adds some
new wrapper methods that are able to raise an Error when needed.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200914135617.1493072-1-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

1 files changed, 35 insertions, 25 deletions

diff --git a/qom/object.c b/qom/object.c
index a91a6a515a..a1ab9a7801 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -403,7 +403,7 @@ bool object_apply_global_props(Object *obj, const GPtrArray *props,
         if (object_dynamic_cast(obj, p->driver) == NULL) {
             continue;
         }
-        if (p->optional && !object_property_find(obj, p->property, NULL)) {
+        if (p->optional && !object_property_find(obj, p->property)) {
             continue;
         }
         p->used = true;
@@ -1214,7 +1214,7 @@ object_property_try_add(Object *obj, const char *name, const char *type,
         return ret;
     }
 
-    if (object_property_find(obj, name, NULL) != NULL) {
+    if (object_property_find(obj, name) != NULL) {
         error_setg(errp, "attempt to add duplicate property '%s' to object (type '%s')",
                    name, object_get_typename(obj));
         return NULL;
@@ -1256,7 +1256,7 @@ object_class_property_add(ObjectClass *klass,
 {
     ObjectProperty *prop;
 
-    assert(!object_class_property_find(klass, name, NULL));
+    assert(!object_class_property_find(klass, name));
 
     prop = g_malloc0(sizeof(*prop));
 
@@ -1273,24 +1273,27 @@ object_class_property_add(ObjectClass *klass,
     return prop;
 }
 
-ObjectProperty *object_property_find(Object *obj, const char *name,
-                                     Error **errp)
+ObjectProperty *object_property_find(Object *obj, const char *name)
 {
     ObjectProperty *prop;
     ObjectClass *klass = object_get_class(obj);
 
-    prop = object_class_property_find(klass, name, NULL);
+    prop = object_class_property_find(klass, name);
     if (prop) {
         return prop;
     }
 
-    prop = g_hash_table_lookup(obj->properties, name);
-    if (prop) {
-        return prop;
-    }
+    return g_hash_table_lookup(obj->properties, name);
+}
 
-    error_setg(errp, "Property '.%s' not found", name);
-    return NULL;
+ObjectProperty *object_property_find_err(Object *obj, const char *name,
+                                         Error **errp)
+{
+    ObjectProperty *prop = object_property_find(obj, name);
+    if (!prop) {
+        error_setg(errp, "Property '.%s' not found", name);
+    }
+    return prop;
 }
 
 void object_property_iter_init(ObjectPropertyIterator *iter,
@@ -1320,27 +1323,34 @@ void object_class_property_iter_init(ObjectPropertyIterator *iter,
     iter->nextclass = object_class_get_parent(klass);
 }
 
-ObjectProperty *object_class_property_find(ObjectClass *klass, const char *name,
-                                           Error **errp)
+ObjectProperty *object_class_property_find(ObjectClass *klass, const char *name)
 {
-    ObjectProperty *prop;
     ObjectClass *parent_klass;
 
     parent_klass = object_class_get_parent(klass);
     if (parent_klass) {
-        prop = object_class_property_find(parent_klass, name, NULL);
+        ObjectProperty *prop =
+            object_class_property_find(parent_klass, name);
         if (prop) {
             return prop;
         }
     }
 
-    prop = g_hash_table_lookup(klass->properties, name);
+    return g_hash_table_lookup(klass->properties, name);
+}
+
+ObjectProperty *object_class_property_find_err(ObjectClass *klass,
+                                               const char *name,
+                                               Error **errp)
+{
+    ObjectProperty *prop = object_class_property_find(klass, name);
     if (!prop) {
         error_setg(errp, "Property '.%s' not found", name);
     }
     return prop;
 }
 
+
 void object_property_del(Object *obj, const char *name)
 {
     ObjectProperty *prop = g_hash_table_lookup(obj->properties, name);
@@ -1355,7 +1365,7 @@ bool object_property_get(Object *obj, const char *name, Visitor *v,
                          Error **errp)
 {
     Error *err = NULL;
-    ObjectProperty *prop = object_property_find(obj, name, errp);
+    ObjectProperty *prop = object_property_find_err(obj, name, errp);
 
     if (prop == NULL) {
         return false;
@@ -1374,7 +1384,7 @@ bool object_property_set(Object *obj, const char *name, Visitor *v,
                          Error **errp)
 {
     Error *err = NULL;
-    ObjectProperty *prop = object_property_find(obj, name, errp);
+    ObjectProperty *prop = object_property_find_err(obj, name, errp);
 
     if (prop == NULL) {
         return false;
@@ -1590,7 +1600,7 @@ int object_property_get_enum(Object *obj, const char *name,
 {
     char *str;
     int ret;
-    ObjectProperty *prop = object_property_find(obj, name, errp);
+    ObjectProperty *prop = object_property_find_err(obj, name, errp);
     EnumProperty *enumprop;
 
     if (prop == NULL) {
@@ -1647,7 +1657,7 @@ out:
 
 const char *object_property_get_type(Object *obj, const char *name, Error **errp)
 {
-    ObjectProperty *prop = object_property_find(obj, name, errp);
+    ObjectProperty *prop = object_property_find_err(obj, name, errp);
     if (prop == NULL) {
         return NULL;
     }
@@ -2025,7 +2035,7 @@ char *object_get_canonical_path(const Object *obj)
 
 Object *object_resolve_path_component(Object *parent, const char *part)
 {
-    ObjectProperty *prop = object_property_find(parent, part, NULL);
+    ObjectProperty *prop = object_property_find(parent, part);
     if (prop == NULL) {
         return NULL;
     }
@@ -2724,8 +2734,8 @@ object_property_add_alias(Object *obj, const char *name,
     ObjectProperty *target_prop;
     g_autofree char *prop_type = NULL;
 
-    target_prop = object_property_find(target_obj, target_name,
-                                       &error_abort);
+    target_prop = object_property_find_err(target_obj, target_name,
+                                           &error_abort);
 
     if (object_property_is_child(target_prop)) {
         prop_type = g_strdup_printf("link%s",
@@ -2758,7 +2768,7 @@ void object_property_set_description(Object *obj, const char *name,
 {
     ObjectProperty *op;
 
-    op = object_property_find(obj, name, &error_abort);
+    op = object_property_find_err(obj, name, &error_abort);
     g_free(op->description);
     op->description = g_strdup(description);
 }