How to Use lua_tostring

[demonguy]

Here is my code

DWORD *Add = (DWORD *)((ModuleBase) + t_luaState);
lua_State *State = (lua_State *)*Add;
s_luapushcclosure(State,(lua_CFunction)os_execute,0);
s_lua_setfield(State,LUA_GLOBALSINDEX,"OSexecute");

the define of struct lua_State is in lua.h (version 5.1.4)
And the i get "Add" by tracing "lua_newstate" and it's 0xABEF10 of 4.3.4(rebased)

int os_execute (lua_State *L) {
  MessageBox(NULL,"1","2",0);
  LUATOSTRING s_lua_tostring = (LUATOSTRING)((ModuleBase) + t_lua_tostring);
  MessageBox(NULL,"1",s_lua_tostring(L,-1),0);
  return 0;
}

i have modified "FrameScript::InvalidPtrChec" , So it won't work

it works fine when i run the macro in WOW as "/run print("OSexecute")"
but when i run "/run OSexecute("123")", after the first MessageBox, WOW crashes... who knows why?

[l0l1dk]

You shouldn't need to cast os_execute to a lua_CFunction when calling s_luapushcclosure; it should already be one. Make sure that os_execute's calling convention is __cdecl. If it isn't __cdecl it will cause the stack will be misaligned after it is called, causing a crash. If that isn't the problem then you should be able to figure out what's causing it by looking at the crash log.

[demonguy]

My default calling convention is __cdecl so the problem won't be it ....

And there is my crash info , I don't know how to debug a injected DLL ... So i don't know how to get information from the crash info ~~~


Someone says that WOW's lua_State is different from standard lua struct lua_State..... is that true??

[Bananenbrot]

1. Use c++ style casts
2. Use a consisten naming scheme
3. http://www.ownedcore.com/forums/worl...ml#post2181478 (Warden confusion?)
4. Lua 5.1 Reference Manual , so lua_tostring is just a macro around lua_tolstring which has an additional parameter. This means you **** up you stack when calling it with less parameters.

[namreeb]

Someone says that WOW's lua_State is different from standard lua struct lua_State..... is that true??

Yes. Or at least it used to be.

[demonguy]

1. Use c++ style casts
2. Use a consisten naming scheme
3. http://www.ownedcore.com/forums/worl...ml#post2181478 (Warden confusion?)
4. Lua 5.1 Reference Manual , so lua_tostring is just a macro around lua_tolstring which has an additional parameter. This means you **** up you stack when calling it with less parameters.

Thanks..... I solved it ....
i misused "luaV_tostring" found in IDA as "lua_tostring"....... So it totally a wrong function .....

But i have another question.... When i includes all lua standard source code , and try to call standard c function by passing WOW's lua_State,,, it always failed. Why?

[migtron]

But i have another question.... When i includes all lua standard source code , and try to call standard c function by passing WOW's lua_State,,, it always failed. Why?

That's because Blizzard is not using stock Lua, but a highly modified version (e.g. to implement the concept of "code taint" to prevent addons from botting). So if you call the "official" Lua functions with Blizzard's lua_State, you are providing them with a different data structure than they expect, leading to errors and/or crashed.

[demonguy]

That's because Blizzard is not using stock Lua, but a highly modified version (e.g. to implement the concept of "code taint" to prevent addons from botting). So if you call the "official" Lua functions with Blizzard's lua_State, you are providing them with a different data structure than they expect, leading to errors and/or crashed.

Oh i see.... Thanks