?RCS: $Id: cpp_stuff.U 1 2006-08-24 12:32:52Z rmanfredi $
?RCS:
?RCS: Copyright (c) 1991-1997, 2004-2006, Raphael Manfredi
?RCS: 
?RCS: You may redistribute only under the terms of the Artistic Licence,
?RCS: as specified in the README file that comes with the distribution.
?RCS: You may reuse parts of this distribution only within the terms of
?RCS: that same Artistic Licence; a copy of which may be found at the root
?RCS: of the source tree for dist 4.0.
?RCS:
?RCS: $Log: cpp_stuff.U,v $
?RCS: Revision 3.0.1.2  1997/02/28  15:30:48  ram
?RCS: patch61: added cute quoting trick for wild stringify support
?RCS:
?RCS: Revision 3.0.1.1  1994/10/29  16:08:24  ram
?RCS: patch36: now uses cppstdin instead of plain cpp for consistency (ADO)
?RCS: patch36: remove temporary files when done
?RCS:
?RCS: Revision 3.0  1993/08/18  12:05:36  ram
?RCS: Baseline for dist 3.0 netwide release.
?RCS:
?MAKE:cpp_stuff cpp_quote: cat contains cppstdin cppflags cppminus rm Warn \
	package
?MAKE:	-pick add $@ %<
?S:cpp_stuff:
?S:	This variable contains an identification of the catenation mechanism
?S:	used by the C preprocessor.
?S:.
?S:cpp_quote:
?S:	This variable is set to either '"' or '' depending on whether the
?S:	pre-processor pre-dates ANSI or not.  It is used in the production of
?S:	the SQuoTe() and EQuoTe() macros, and was introduced to overcome a bug
?S:	in gcc 3.x whereby the pre-processor complained loudly about the
?S:	unterminated strings.
?S:.
?C:CAT2:
?C:	This macro catenates 2 tokens together.
?C:.
?C:CAT3:
?C:	This macro catenates 3 tokens together.
?C:.
?C:CAT4:
?C:	This macro catenates 4 tokens together.
?C:.
?C:CAT5:
?C:	This macro catenates 5 tokens together.
?C:.
?C:STRINGIFY:
?C:	This macro surrounds its token with double quotes.
?C:.
?C:SCAT2:
?C:	This macro catenates 2 tokens together and stringifies the result.
?C:.
?C:SCAT3:
?C:	This macro catenates 3 tokens together and stringifies the result.
?C:.
?C:SCAT4:
?C:	This macro catenates 4 tokens together and stringifies the result.
?C:.
?C:SCAT5:
?C:	This macro catenates 5 tokens together and stringifies the result.
?C:.
?H:?%<:#if $cpp_stuff == 1
?H:?CAT2:#define CAT2(a,b)a/**/b
?H:?CAT3:#define CAT3(a,b,c)a/**/b/**/c
?H:?CAT4:#define CAT4(a,b,c,d)a/**/b/**/c/**/d
?H:?CAT5:#define CAT5(a,b,c,d,e)a/**/b/**/c/**/d/**/e
?H:?STRINGIFY:#define STRINGIFY(a)"a"
?H:?%<:#define SQuoTe(a)${cpp_quote}a
?H:?%<:#define EQuoTe(a)a${cpp_quote}
?H:?SCAT2:#define SCAT2(a,b)EQuoTe(SQuoTe(a)b)
?H:?SCAT3:#define SCAT3(a,b,c)EQuoTe(SQuoTe(a)b/**/c)
?H:?SCAT4:#define SCAT4(a,b,c,d)EQuoTe(SQuoTe(a)b/**/c/**/d)
?H:?SCAT5:#define SCAT5(a,b,c,d,e)EQuoTe(SQuoTe(a)b/**/c/**/d/**/e)
?H:?%<:#endif
?H:?%<:#if $cpp_stuff == 42
?X: The additional level of indirection enables these macros to be
?X: used as arguments to other macros.  See K&R 2nd ed., page 231.
?H:?%<:#define CaTiFy(a,b) a ## b
?H:?%<:#define CAT2(a,b) CaTiFy(a,b)
?H:?CAT3:#define CAT3(a,b,c) CAT2(CaTiFy(a,b),c)
?H:?CAT4:#define CAT4(a,b,c,d) CAT2(CaTiFy(a,b), CaTiFy(c,d))
?H:?CAT5:#define CAT5(a,b,c,d,e) CAT2(CAT2(CaTiFy(a,b), CaTiFy(c,d)), e)
?H:?%<:#define StGiFy(a)# a
?H:?STRINGIFY:#define STRINGIFY(a)StGiFy(a)
?H:?SCAT2:#define SCAT2(a,b)StGiFy(a) StGiFy(b)
?H:?SCAT3:#define SCAT3(a,b,c)StGiFy(a) StGiFy(b) StGiFy(c)
?H:?SCAT4:#define SCAT4(a,b,c,d)StGiFy(a) StGiFy(b) StGiFy(c) StGiFy(d)
?H:?SCAT5:#define SCAT5(a,b,c,d,e)StGiFy(a) StGiFy(b) StGiFy(c) StGiFy(d) StGiFy(e)
?H:?%<:#endif
?H:?%<:#if $cpp_stuff != 1 && $cpp_stuff != 42
?H:?%<:#include "Bletch: How does this C preprocessor catenate tokens?"
?H:?%<:#endif
?H:.
?W:%<:CAT2 CAT3 CAT4 CAT5 STRINGIFY SCAT2 SCAT3 SCAT4 SCAT5
?F:!cpp_stuff.c
?LINT:known StGiFy EQuoTe SQuoTe CaTiFy
: how do we catenate cpp tokens here?
echo " "
echo "Checking to see how your cpp does stuff like catenate tokens..." >&4
cpp_quote=''
$cat >cpp_stuff.c <<'EOCP'
#define RCAT(a,b)a/**/b
#define ACAT(a,b)a ## b
RCAT(Rei,ser)
ACAT(Cir,cus)
EOCP
$cppstdin $cppflags $cppminus <cpp_stuff.c >cpp_stuff.out 2>&1
if $contains 'Circus' cpp_stuff.out >/dev/null 2>&1; then
	echo "Oh!  Smells like ANSI's been here."
	echo "We can catify or stringify, separately or together!"
	cpp_stuff=42
elif $contains 'Reiser' cpp_stuff.out >/dev/null 2>&1; then
	echo "Ah, yes!  The good old days!"
	cpp_stuff=1
	$cat >cpp_stuff.c <<'EOCP'
#define SQuoTe(a)"a
#define EQuoTe(a)a"
#define CAT2(a,b)EQuoTe(SQuoTe(a)b)
CAT2(Vic,tory)
EOCP
	$cppstdin $cppflags $cppminus <cpp_stuff.c >cpp_stuff.out 2>&1
	if $contains '"Victory"' cpp_stuff.out >/dev/null 2>&1; then
		echo "I'll resort to a cute trick to also be able to stringify."
		cpp_quote='"'
	else
		$cat <<EOM
However, in the good old days we don't know how to stringify and
catify at the same time...
@if SCAT2 || SCAT3 || SCAT4 || SCAT5
You might have to edit the values of the SCAT[2-5] macros in config.h...
@else
Hopefully, $package does not need this feature.
@end
EOM
	fi
else
	./warn <<EOM
I can't seem to be able to catenate tokens with your cpp.
@if CAT2 || CAT3 || CAT4 || CAT5 || SCAT2 || SCAT3 || SCAT4 || SCAT5
You're going to have to edit the values of the following
macros in config.h:

@if CAT2 || CAT3 || CAT4 || CAT5
	CAT[2-5]
@end
@if SCAT2 || SCAT3 || SCAT4 || SCAT5
	SCAT[2-5]
@end

in order to let me compile.
@end
EOM
	cpp_stuff="/* Help! How do we handle cpp_stuff? */*/"
fi
$rm -f cpp_stuff.*