Mercurial > lua-getsize / changeset

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/getsize.c	Sat Oct 10 17:30:57 2009 +0100
@@ -0,0 +1,82 @@
+/* lua-getsize
+   Author: (C) 2009 Matthew Wild
+   License: MIT/X11 license
+   Description: Adds a debug.getsize() function which
+                returns the size in bytes of a Lua object
+*/
+
+#include <stdio.h>
+
+#include <lua.h>
+#include <lstate.h>
+#include <lobject.h>
+#include <lfunc.h>
+
+int debug_getsize(lua_State* L)
+{
+  TValue* o = L->base;
+  switch (o->tt) {
+    /* Container types */
+    case LUA_TTABLE: {
+      Table *h = hvalue(o);
+      printf("Size of array: %p\n", h->array);
+      lua_pushinteger(L, sizeof(Table) + sizeof(TValue) * h->sizearray +
+                             sizeof(Node) * sizenode(h));
+      break;
+    }
+    case LUA_TFUNCTION: {
+      Closure *cl = clvalue(o);
+      lua_pushinteger(L, (cl->c.isC) ? sizeCclosure(cl->c.nupvalues) :
+                           sizeLclosure(cl->l.nupvalues));
+      break;
+    }
+    case LUA_TTHREAD: {
+      lua_State *th = thvalue(o);
+      lua_pushinteger(L, sizeof(lua_State) + sizeof(TValue) * th->stacksize +
+                                 sizeof(CallInfo) * th->size_ci);
+      break;
+    }
+    case LUA_TPROTO: {
+      Proto *p = pvalue(o);
+      lua_pushinteger(L, sizeof(Proto) + sizeof(Instruction) * p->sizecode +
+                             sizeof(Proto *) * p->sizep +
+                             sizeof(TValue) * p->sizek + 
+                             sizeof(int) * p->sizelineinfo +
+                             sizeof(LocVar) * p->sizelocvars +
+                             sizeof(TString *) * p->sizeupvalues);
+     break;
+    }
+    /* Non-containers */
+    case LUA_TUSERDATA: {
+      lua_pushnumber(L, uvalue(o)->len);
+      break;
+    }
+    case LUA_TLIGHTUSERDATA: {
+      lua_pushnumber(L, sizeof(void*));
+      break;
+    }
+    case LUA_TSTRING: {
+      TString *s = rawtsvalue(o);
+      lua_pushinteger(L, sizeof(TString) + s->tsv.len + 1);
+      break;
+    }
+    case LUA_TNUMBER: {
+      lua_pushinteger(L, sizeof(lua_Number));
+      break;
+    }
+    case LUA_TBOOLEAN: {
+      lua_pushinteger(L, sizeof(int));
+      break;
+    }
+    default: return 0;
+  }
+  return 1;
+}
+
+int luaopen_getsize(lua_State* L)
+{
+	lua_getglobal(L, "debug");
+	lua_pushcfunction(L, debug_getsize);
+	lua_setfield(L, -2, "getsize");
+	return 0;
+}