Reduce code duplication with luaA_*_call_handler (#2321)

The functions luaA_class_call_handler() and luaA_mouse_call_handler()
are basically identical. Fix this code duplication by moving this to
luaA_call_handler() in lualib.h.

Signed-off-by: Uli Schlachter <psychon@znc.in>

common/luaclass.c

@@ -389,40 +389,6 @@ luaA_class_property_get(lua_State *L, lua_class_t *lua_class, int fieldidx)
     return NULL;
 }
 
-/** Call a registered function.
- * \param L The Lua VM state.
- * \param handler The function to call.
- * \return The number of elements pushed on stack.
- */
-static
-int luaA_class_call_handler(lua_State *L, int handler)
-{
-    /* This is based on luaA_dofunction, but allows multiple return values */
-    assert(handler != LUA_REFNIL);
-
-    int nargs = lua_gettop(L);
-
-    /* Push error handling function and move it before args */
-    lua_pushcfunction(L, luaA_dofunction_error);
-    lua_insert(L, - nargs - 1);
-    int error_func_pos = 1;
-
-    /* push function and move it before args */
-    lua_rawgeti(L, LUA_REGISTRYINDEX, handler);
-    lua_insert(L, - nargs - 1);
-
-    if(lua_pcall(L, nargs, LUA_MULTRET, error_func_pos))
-    {
-        warn("%s", lua_tostring(L, -1));
-        /* Remove error function and error string */
-        lua_pop(L, 2);
-        return 0;
-    }
-    /* Remove error function */
-    lua_remove(L, error_func_pos);
-    return lua_gettop(L);
-}
-
 /** Generic index meta function for objects.
  * \param L The Lua VM state.
  * \return The number of elements pushed on stack.
@@ -471,7 +437,7 @@ luaA_class_index(lua_State *L)
     else
     {
         if(class->index_miss_handler != LUA_REFNIL)
-            return luaA_class_call_handler(L, class->index_miss_handler);
+            return luaA_call_handler(L, class->index_miss_handler);
         if(class->index_miss_property)
             return class->index_miss_property(L, luaA_checkudata(L, 1, class));
     }
@@ -503,7 +469,7 @@ luaA_class_newindex(lua_State *L)
     else
     {
         if(class->newindex_miss_handler != LUA_REFNIL)
-            return luaA_class_call_handler(L, class->newindex_miss_handler);
+            return luaA_call_handler(L, class->newindex_miss_handler);
         if(class->newindex_miss_property)
             return class->newindex_miss_property(L, luaA_checkudata(L, 1, class));
     }

common/lualib.h

@@ -23,6 +23,7 @@
 #define AWESOME_COMMON_LUALIB
 
 #include <lua.h>
+#include <lauxlib.h>
 
 #include "common/util.h"
 
@@ -84,6 +85,40 @@ luaA_dofunction(lua_State *L, int nargs, int nret)
     return true;
 }
 
+/** Call a registered function. Its arguments are the complete stack contents.
+ * \param L The Lua VM state.
+ * \param handler The function to call.
+ * \return The number of elements pushed on stack.
+ */
+static inline
+int luaA_call_handler(lua_State *L, int handler)
+{
+    /* This is based on luaA_dofunction, but allows multiple return values */
+    assert(handler != LUA_REFNIL);
+
+    int nargs = lua_gettop(L);
+
+    /* Push error handling function and move it before args */
+    lua_pushcfunction(L, luaA_dofunction_error);
+    lua_insert(L, - nargs - 1);
+    int error_func_pos = 1;
+
+    /* push function and move it before args */
+    lua_rawgeti(L, LUA_REGISTRYINDEX, handler);
+    lua_insert(L, - nargs - 1);
+
+    if(lua_pcall(L, nargs, LUA_MULTRET, error_func_pos))
+    {
+        warn("%s", lua_tostring(L, -1));
+        /* Remove error function and error string */
+        lua_pop(L, 2);
+        return 0;
+    }
+    /* Remove error function */
+    lua_remove(L, error_func_pos);
+    return lua_gettop(L);
+}
+
 #endif
 
 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80

mouse.c

@@ -142,39 +142,6 @@ mouse_warp_pointer(xcb_window_t window, int16_t x, int16_t y)
                      0, 0, 0, 0, x, y);
 }
 
-/**
- * Allow the a Lua handler to be implemented for custom properties and
- * functions.
- * \param L A lua state
- * \param handler A function on the LUA_REGISTRYINDEX
- */
-static int
-luaA_mouse_call_handler(lua_State *L, int handler)
-{
-    int nargs = lua_gettop(L);
-
-    /* Push error handling function and move it before args */
-    lua_pushcfunction(L, luaA_dofunction_error);
-    lua_insert(L, - nargs - 1);
-    int error_func_pos = 1;
-
-    /* push function and move it before args */
-    lua_rawgeti(L, LUA_REGISTRYINDEX, handler);
-    lua_insert(L, - nargs - 1);
-
-    if(lua_pcall(L, nargs, LUA_MULTRET, error_func_pos))
-    {
-        warn("%s", lua_tostring(L, -1));
-        /* Remove error function and error string */
-        lua_pop(L, 2);
-        return 0;
-    }
-    /* Remove error function */
-    lua_remove(L, error_func_pos);
-
-    return lua_gettop(L);
-}
-
 /** Mouse library.
  * \param L The Lua VM state.
  * \return The number of elements pushed on stack.
@@ -191,7 +158,7 @@ luaA_mouse_index(lua_State *L)
     /* attr is not "screen"?! */
     if (A_STRNEQ(attr, "screen")) {
         if (miss_index_handler != LUA_REFNIL) {
-            return luaA_mouse_call_handler(L, miss_index_handler);
+            return luaA_call_handler(L, miss_index_handler);
         }
         else
             return luaA_default_index(L);
@@ -226,7 +193,7 @@ luaA_mouse_newindex(lua_State *L)
     if (A_STRNEQ(attr, "screen")) {
         /* Call the lua mouse property handler */
         if (miss_newindex_handler != LUA_REFNIL) {
-            return luaA_mouse_call_handler(L, miss_newindex_handler);
+            return luaA_call_handler(L, miss_newindex_handler);
         }
         else
             return luaA_default_newindex(L);