1 /* Symbol concatenation utilities.
2 
3    Copyright (C) 1998, 2000 Free Software Foundation, Inc.
4 
5    This program is free software; you can redistribute it and/or modify
6    it under the terms of the GNU General Public License as published by
7    the Free Software Foundation; either version 2 of the License, or
8    (at your option) any later version.
9 
10    This program is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13    GNU General Public License for more details.
14 
15    You should have received a copy of the GNU General Public License along
16    with this program; if not, write to the Free Software Foundation, Inc.,
17    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
18 
19 #ifndef SYM_CAT_H
20 #define SYM_CAT_H
21 
22 #if defined (__STDC__) || defined (ALMOST_STDC) || defined (HAVE_STRINGIZE)
23 #define CONCAT2(a,b)	 a##b
24 #define CONCAT3(a,b,c)	 a##b##c
25 #define CONCAT4(a,b,c,d) a##b##c##d
26 #define STRINGX(s) #s
27 #else
28 /* Note one should never pass extra whitespace to the CONCATn macros,
29    e.g. CONCAT2(foo, bar) because traditonal C will keep the space between
30    the two labels instead of concatenating them.  Instead, make sure to
31    write CONCAT2(foo,bar).  */
32 #define CONCAT2(a,b)	 a/**/b
33 #define CONCAT3(a,b,c)	 a/**/b/**/c
34 #define CONCAT4(a,b,c,d) a/**/b/**/c/**/d
35 #define STRINGX(s) "s"
36 #endif
37 
38 #define XCONCAT2(a,b)     CONCAT2(a,b)
39 #define XCONCAT3(a,b,c)   CONCAT3(a,b,c)
40 #define XCONCAT4(a,b,c,d) CONCAT4(a,b,c,d)
41 
42 /* Note the layer of indirection here is typically used to allow
43    stringification of the expansion of macros.  I.e. "#define foo
44    bar", "XSTRING(foo)", to yield "bar".  Be aware that this only
45    works for __STDC__, not for traditional C which will still resolve
46    to "foo".  */
47 #define XSTRING(s) STRINGX(s)
48 
49 #endif /* SYM_CAT_H */
50