gamedevlists-windows

RE: [GD-Windows] variadic macros

[Paul B. <pa...@wi...>]

> -----Original Message-----
> From: gam...@li...=20
> [mailto:gam...@li...] On=20
> Behalf Of Brett Bibby
> Sent: Tuesday, December 21, 2004 1:55 AM
> To: Gam...@li...
> Subject: [GD-Windows] variadic macros
>=20
> Is there any way to support variadic macros in Visual Studio=20
> like gcc supports?  If not, how do people write stuff like=20
> custom asserts that take variable parameters?
>=20
> http://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html
>=20
> Thanks!
> Brett


Depending on what you're after, you might find that the __noop
intrinsic will help you out.


#ifdef _DEBUG
void _MyDebugPrintf(const char* fmt, ...);
#define DPF _MyDebugPrintf
#else
#define DPF __noop
#endif

// later, ...

	DPF("%s %s this works", FuncA(), FuncB());

FuncA and FuncB (or parameters in general) are not evaluated
in non _DEBUG builds.  The compiler ignores the statement.

This is obviously not variadic macros, but you can do quite a
bit with it.

Paul

RE: [GD-Windows] variadic macros

[Paul B. <pa...@wi...>]

> -----Original Message-----
> From: gam...@li...=20
> [mailto:gam...@li...] On=20
> Behalf Of Brett Bibby
> Sent: Tuesday, December 21, 2004 2:42 AM
> To: gam...@li...
> Subject: Re: [GD-Windows] variadic macros
>=20
> > Paul Bleisch wrote:
> > Depending on what you're after, you might find that the __noop=20
> > intrinsic will help you out.
> >
>=20
> That's new, thanks.  I don't think I can use it still though=20
> as I need to insert some parameters before calling the debug function.
>=20
> This is what we have on other platforms:
>=20
> #define MPE_SHELL_ERROR_LOG(...) \
>   MpiShellLogTextAdd(__FILE__, \
>        (MpeChar *)__func__, \
>        __LINE__, \
>        MPE_SHELL_LOG_FLAG_ERROR, \
>        __VA_ARGS__)
>=20
>=20
> I want to insert the file, func and line number.  (BTW, does=20
> windows allow __func__ ?)
>=20
> Thanks again,
> Brett


__func__ is not, but __FUNCTION__ is available (which I think is
equivalent).

A potential workaround for your varargs macros is to do something like:

#ifdef _DEBUG
void _SetDebugInfo(MpeChar* file, MpeChar* func, int line, unsigned
flags);
void _DebugPrint(char* fmt, ...);
#define MPE_SHELL_ERROR_LOG _SetDebugInfo(__FILE__, __FUNCTION__,
__LINE__, MPE_SHELL_LOG_FLAG_ERROR), _DebugPrint
#else
#define MPE_SHELL_ERROR_LOG __noop
#endif

this is not threadsafe and not a 1:1 replacement for your current code,
so beware.

Paul

Re: [GD-Windows] variadic macros

[Brett B. <res...@ga...>]

> Paul Bleisch wrote:
> Depending on what you're after, you might find that the __noop
> intrinsic will help you out.
>

That's new, thanks.  I don't think I can use it still though as I need to
insert some parameters before calling the debug function.

This is what we have on other platforms:

#define MPE_SHELL_ERROR_LOG(...) \
  MpiShellLogTextAdd(__FILE__, \
       (MpeChar *)__func__, \
       __LINE__, \
       MPE_SHELL_LOG_FLAG_ERROR, \
       __VA_ARGS__)


I want to insert the file, func and line number.  (BTW, does windows allow
__func__ ?)

Thanks again,
Brett