Re: Lua 5.2 string formatting check fails when using integers

[Roberto Ierusalimschy <roberto@...>]

> This is how I ended up solving it (note the LUA_NUMBER_INTEGER define):
> 
> 
>         case 'd':  case 'i': {
>           lua_Number n = luaL_checknumber(L, arg);
> #ifndef LUA_NUMBER_INTEGER
>           luaL_argcheck(L, (MIN_INTFRM - 1) < n && n < (MAX_INTFRM + 1), arg,
>                         "not a number in proper range");
> #endif
>           addlenmod(form, LUA_INTFRMLEN);
>           nb = sprintf(buff, form, (LUA_INTFRM_T)n);
>           break;
>         }
>         case 'o':  case 'u':  case 'x':  case 'X': {
>           lua_Number n = luaL_checknumber(L, arg);
> #ifndef LUA_NUMBER_INTEGER
>           luaL_argcheck(L, 0 <= n && n < (MAX_UINTFRM + 1), arg,
>                         "not a non-negative number in proper range");
> #endif
>           addlenmod(form, LUA_INTFRMLEN);
>           nb = sprintf(buff, form, (unsigned LUA_INTFRM_T)n);
>           break;
>         }

Maybe it would be a little more "elegant" to use some macros to
abstract the tests, and then add those 'ifdefs' around the macros.
Something like this:

#ifdef LUA_NUMBER_INTEGER
#define checkintrange(L,n,arg)		(void)0;
#else
#define MAX_INTFRM      ((lua_Number)((~(unsigned LUA_INTFRM_T)0)/2))
#define MIN_INTFRM      (-(lua_Number)((~(unsigned LUA_INTFRM_T)0)/2) - 1)
#define checkintrange(L,n,arg)
  luaL_argcheck(L, (MIN_INTFRM - 1) < n && n < (MAX_INTFRM + 1), arg, \
    "not a number in proper range");
#endif
...
        case 'd':  case 'i': {
          lua_Number n = luaL_checknumber(L, arg);
          checkintrange(L, n, arg);
          addlenmod(form, LUA_INTFRMLEN);


-- Roberto