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    51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, 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 */