commit c5836a2: [Minor] Add helper to alter metatables

[Vsevolod Stakhov]

Author: Vsevolod Stakhov
Date: 2020-03-04 12:47:45 +0000
URL: https://github.com/rspamd/rspamd/commit/c5836a23f9bb91872f33375914baa02bca4001ca

[Minor] Add helper to alter metatables

---
 src/lua/lua_common.c | 18 ++++++++++++++++++
 src/lua/lua_common.h |  9 +++++++++
 src/lua/lua_worker.c |  1 +
 3 files changed, 28 insertions(+)

diff --git a/src/lua/lua_common.c b/src/lua/lua_common.c
index 2087fe592..ce5fff6c5 100644
--- a/src/lua/lua_common.c
+++ b/src/lua/lua_common.c
@@ -197,6 +197,24 @@ rspamd_lua_setclass (lua_State * L, const gchar *classname, gint objidx)
 	lua_setmetatable (L, objidx);
 }
 
+void
+rspamd_lua_add_metamethod (lua_State *L, const gchar *classname,
+								luaL_Reg *meth)
+{
+	khiter_t k;
+
+	k = kh_get (lua_class_set, lua_classes, classname);
+
+	g_assert (k != kh_end (lua_classes));
+	/* get metatable identified by pointer */
+	lua_rawgetp (L, LUA_REGISTRYINDEX,
+			RSPAMD_LIGHTUSERDATA_MASK (kh_key (lua_classes, k)));
+
+	lua_pushcfunction (L, meth->func);
+	lua_setfield (L, -2, meth->name);
+	lua_pop (L, 1); /* remove metatable */
+}
+
 /* assume that table is at the top */
 void
 rspamd_lua_table_set (lua_State * L, const gchar *index, const gchar *value)
diff --git a/src/lua/lua_common.h b/src/lua/lua_common.h
index 53e925832..aea6ebf26 100644
--- a/src/lua/lua_common.h
+++ b/src/lua/lua_common.h
@@ -161,6 +161,15 @@ void rspamd_lua_new_class (lua_State *L,
  */
 void rspamd_lua_setclass (lua_State *L, const gchar *classname, gint objidx);
 
+/**
+ * Adds a new field to the class (metatable) identified by `classname`
+ * @param L
+ * @param classname
+ * @param meth
+ */
+void rspamd_lua_add_metamethod (lua_State *L, const gchar *classname,
+		luaL_Reg *meth);
+
 /**
  * Set index of table to value (like t['index'] = value)
  */
diff --git a/src/lua/lua_worker.c b/src/lua/lua_worker.c
index f7f4b3c68..a286069cb 100644
--- a/src/lua/lua_worker.c
+++ b/src/lua/lua_worker.c
@@ -47,6 +47,7 @@ LUA_FUNCTION_DEF (worker, add_control_handler);
 
 const luaL_reg worker_reg[] = {
 		LUA_INTERFACE_DEF (worker, get_name),
+		{"get_type", lua_worker_get_name},
 		LUA_INTERFACE_DEF (worker, get_stat),
 		LUA_INTERFACE_DEF (worker, get_index),
 		LUA_INTERFACE_DEF (worker, get_count),