Replace lua_newtable() with lua_createtable()

Lua can preallocate space in table for array or non-array elements type.
This should improve performance when setting table, so when we can we
use lua_createtable() since this is just a gain.

Signed-off-by: Julien Danjou <julien@danjou.info>

client.c

@@ -1598,7 +1598,7 @@ luaA_client_geometry(lua_State *L)
 static inline int
 luaA_pushstruts(lua_State *L, strut_t struts)
 {
-    lua_newtable(L);
+    lua_createtable(L, 4, 0);
     lua_pushnumber(L, struts.left);
     lua_setfield(L, -2, "left");
     lua_pushnumber(L, struts.right);
@@ -1980,7 +1980,7 @@ luaA_client_index(lua_State *L)
         {
             const char *u_or_p = NULL;
 
-            lua_newtable(L);
+            lua_createtable(L, 0, 1);
 
             if(c->size_hints.flags & XCB_SIZE_HINT_US_POSITION)
                 u_or_p = "user_position";
@@ -1989,7 +1989,7 @@ luaA_client_index(lua_State *L)
 
             if(u_or_p)
             {
-                lua_newtable(L);
+                lua_createtable(L, 0, 2);
                 lua_pushnumber(L, c->size_hints.x);
                 lua_setfield(L, -2, "x");
                 lua_pushnumber(L, c->size_hints.y);
@@ -2005,7 +2005,7 @@ luaA_client_index(lua_State *L)
 
             if(u_or_p)
             {
-                lua_newtable(L);
+                lua_createtable(L, 0, 2);
                 lua_pushnumber(L, c->size_hints.width);
                 lua_setfield(L, -2, "width");
                 lua_pushnumber(L, c->size_hints.height);

dbus.c

@@ -72,15 +72,17 @@ a_dbus_message_iter(DBusMessageIter *iter)
             break;
           case DBUS_TYPE_STRUCT:
             {
-                /* create a new table to store all the value */
-                lua_newtable(globalconf.L);
-
                 DBusMessageIter subiter;
                 /* initialize a sub iterator */
                 dbus_message_iter_recurse(iter, &subiter);
-                /* create a new table to store the dict */
+
                 int n = a_dbus_message_iter(&subiter);
 
+                /* create a new table to store all the value */
+                lua_createtable(globalconf.L, n, 0);
+                /* move the table before array elements */
+                lua_insert(globalconf.L, - n - 1);
+
                 for(int i = n; i > 0; i--)
                     lua_rawseti(globalconf.L, - i - 1, i);
             }
@@ -102,8 +104,8 @@ a_dbus_message_iter(DBusMessageIter *iter)
                       case dbustype: \
                         { \
                             const type *data; \
-                            lua_newtable(globalconf.L); \
                             dbus_message_iter_get_fixed_array(&sub, &data, &datalen); \
+                            lua_createtable(globalconf.L, datalen, 0); \
                             for(int i = 0; i < datalen; i++) \
                             { \
                                 lua_pushnumber(globalconf.L, data[i]); \
@@ -129,8 +131,8 @@ a_dbus_message_iter(DBusMessageIter *iter)
                       case DBUS_TYPE_BOOLEAN:
                         {
                             const bool *b;
-                            lua_newtable(globalconf.L);
                             dbus_message_iter_get_fixed_array(&sub, &b, &datalen);
+                            lua_createtable(globalconf.L, datalen, 0);
                             for(int i = 0; i < datalen; i++)
                             {
                                 lua_pushboolean(globalconf.L, b[i]);
@@ -143,30 +145,35 @@ a_dbus_message_iter(DBusMessageIter *iter)
                 else if(array_type == DBUS_TYPE_DICT_ENTRY)
                 {
                     DBusMessageIter subiter;
-
-                    lua_newtable(globalconf.L);
-
                     /* initialize a sub iterator */
                     dbus_message_iter_recurse(iter, &subiter);
+
                     /* get the keys and the values
-                     * n is the number of entry in * dict */
+                     * n is the number of entry in dict */
                     int n = a_dbus_message_iter(&subiter);
 
+                    /* create a new table to store all the value */
+                    lua_createtable(globalconf.L, n, 0);
+                    /* move the table before array elements */
+                    lua_insert(globalconf.L, - (n * 2) - 1);
+
                     for(int i = 0; i < n; i ++)
                         lua_rawset(globalconf.L, - (n * 2) - 1 + i * 2);
                 }
                 else
                 {
                     DBusMessageIter subiter;
-
-                    lua_newtable(globalconf.L);
-
                     /* prepare to dig into the array*/
                     dbus_message_iter_recurse(iter, &subiter);
 
                     /* now iterate over every element of the array */
                     int n = a_dbus_message_iter(&subiter);
 
+                    /* create a new table to store all the value */
+                    lua_createtable(globalconf.L, n, 0);
+                    /* move the table before array elements */
+                    lua_insert(globalconf.L, - n - 1);
+
                     for(int i = n; i > 0; i--)
                         lua_rawseti(globalconf.L, - i - 1, i);
                 }
@@ -225,7 +232,7 @@ a_dbus_process_request(DBusConnection *dbus_connection, DBusMessage *msg)
     if(globalconf.hooks.dbus == LUA_REFNIL)
         return;
 
-    lua_newtable(globalconf.L);
+    lua_createtable(globalconf.L, 0, 5);
 
     switch(dbus_message_get_type(msg))
     {

keygrabber.c

@@ -692,7 +692,7 @@ keygrabber_handlekpress(lua_State *L, xcb_key_press_event_t *e)
     if(!key_press_lookup_string(e, buf, countof(buf), &ksym))
         return false;
 
-    lua_newtable(L);
+    lua_createtable(L, 0, 8);
 
     lua_pushboolean(L, e->state & XCB_MOD_MASK_CONTROL);
     lua_setfield(L, -2, "Control");

luaa.c

@@ -418,7 +418,7 @@ luaA_table2wtable(lua_State *L)
         return;
 
     lua_newtable(L); /* create *real* content table */
-    lua_newtable(L); /* metatable */
+    lua_createtable(L, 0, 5); /* metatable */
     lua_pushvalue(L, -2); /* copy content table */
     lua_pushcfunction(L, luaA_ipairs_aux); /* push ipairs aux */
     lua_pushcclosure(L, luaA_wtable_ipairs, 2);

luaa.h

@@ -173,7 +173,7 @@ luaA_getopt_boolean(lua_State *L, int idx, const char *name, bool def)
 static inline int
 luaA_pusharea(lua_State *L, area_t geometry)
 {
-    lua_newtable(L);
+    lua_createtable(L, 0, 4);
     lua_pushnumber(L, geometry.x);
     lua_setfield(L, -2, "x");
     lua_pushnumber(L, geometry.y);
@@ -316,7 +316,7 @@ luaA_getopt_padding(lua_State *L, int idx, padding_t *dpadding)
 static inline int
 luaA_pushpadding(lua_State *L, padding_t *padding)
 {
-    lua_newtable(L);
+    lua_createtable(L, 0, 4);
     lua_pushnumber(L, padding->right);
     lua_setfield(L, -2, "right");
     lua_pushnumber(L, padding->left);

mouse.c

@@ -393,13 +393,13 @@ luaA_mouse_newindex(lua_State *L)
 int
 luaA_mouse_pushstatus(lua_State *L, int x, int y, uint16_t mask)
 {
-    lua_newtable(L);
+    lua_createtable(L, 0, 2);
     lua_pushnumber(L, x);
     lua_setfield(L, -2, "x");
     lua_pushnumber(L, y);
     lua_setfield(L, -2, "y");
 
-    lua_newtable(L);
+    lua_createtable(L, 5, 0);
 
     int i = 1;
 

screen.c

@@ -431,7 +431,7 @@ luaA_screen_tags(lua_State *L)
     }
     else
     {
-        lua_newtable(L);
+        lua_createtable(L, s->tags.len, 0);
         for(i = 0; i < s->tags.len; i++)
         {
             tag_push(L, s->tags.tab[i]);

spawn.c

@@ -77,7 +77,7 @@ spawn_monitor_event(SnMonitorEvent *event, void *data)
     SnStartupSequence *sequence = sn_monitor_event_get_startup_sequence(event);
     SnMonitorEventType event_type = sn_monitor_event_get_type(event);
 
-    lua_newtable(globalconf.L);
+    lua_createtable(globalconf.L, 0, 2);
     lua_pushstring(globalconf.L, sn_startup_sequence_get_id(sequence));
     lua_setfield(globalconf.L, -2, "id");