contrib/sendmail/include/sm/cdefs.h

   1 /*
   2  * Copyright (c) 2000-2002 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  *
   5  * By using this file, you agree to the terms and conditions set
   6  * forth in the LICENSE file which can be found at the top level of
   7  * the sendmail distribution.
   8  *
   9  *      $Id: cdefs.h,v 1.15 2002/01/16 18:30:11 ca Exp $
  10  */
  11
  12 /*
  13 **  libsm C language portability macros
  14 **  See libsm/cdefs.html for documentation.
  15 */
  16
  17 #ifndef SM_CDEFS_H
  18 # define SM_CDEFS_H
  19
  20 # include <sm/config.h>
  21
  22 /*
  23 **  BSD and Linux have <sys/cdefs.h> which defines a set of C language
  24 **  portability macros that are a defacto standard in the open source
  25 **  community.
  26 */
  27
  28 # if SM_CONF_SYS_CDEFS_H
  29 #  include <sys/cdefs.h>
  30 # endif /* SM_CONF_SYS_CDEFS_H */
  31
  32 /*
  33 **  Define the standard C language portability macros
  34 **  for platforms that lack <sys/cdefs.h>.
  35 */
  36
  37 # if !SM_CONF_SYS_CDEFS_H
  38 #  if defined(__cplusplus)
  39 #   define      __BEGIN_DECLS   extern "C" {
  40 #   define      __END_DECLS     };
  41 #  else /* defined(__cplusplus) */
  42 #   define      __BEGIN_DECLS
  43 #   define      __END_DECLS
  44 #  endif /* defined(__cplusplus) */
  45 #  if defined(__STDC__) || defined(__cplusplus)
  46 #   ifndef __P
  47 #    define     __P(protos)     protos
  48 #   endif /* __P */
  49 #   define      __CONCAT(x,y)   x ## y
  50 #   define      __STRING(x)     #x
  51 #  else /* defined(__STDC__) || defined(__cplusplus) */
  52 #   define      __P(protos)     ()
  53 #   define      __CONCAT(x,y)   x/**/y
  54 #   define      __STRING(x)     "x"
  55 #   define      const
  56 #   define      signed
  57 #   define      volatile
  58 #  endif /* defined(__STDC__) || defined(__cplusplus) */
  59 # endif /* !SM_CONF_SYS_CDEFS_H */
  60
  61 /*
  62 **  Define SM_DEAD, a macro used to declare functions that do not return
  63 **  to their caller.
  64 */
  65
  66 # ifndef SM_DEAD
  67 #  if __GNUC__ >= 2
  68 #   if __GNUC__ == 2 && __GNUC_MINOR__ < 5
  69 #    define SM_DEAD(proto) volatile proto
  70 #   else /* __GNUC__ == 2 && __GNUC_MINOR__ < 5 */
  71 #    define SM_DEAD(proto) proto __attribute__((__noreturn__))
  72 #   endif /* __GNUC__ == 2 && __GNUC_MINOR__ < 5 */
  73 #  else /* __GNUC__ >= 2 */
  74 #   define SM_DEAD(proto) proto
  75 #  endif /* __GNUC__ >= 2 */
  76 # endif /* SM_DEAD */
  77
  78 /*
  79 **  Define SM_UNUSED, a macro used to declare variables that may be unused.
  80 */
  81
  82 # ifndef SM_UNUSED
  83 #  if __GNUC__ >= 2
  84 #   if __GNUC__ == 2 && __GNUC_MINOR__ < 7
  85 #    define SM_UNUSED(decl) decl
  86 #   else /* __GNUC__ == 2 && __GNUC_MINOR__ < 7 */
  87 #    define SM_UNUSED(decl) decl __attribute__((__unused__))
  88 #   endif /* __GNUC__ == 2 && __GNUC_MINOR__ < 7 */
  89 #  else /* __GNUC__ >= 2 */
  90 #   define SM_UNUSED(decl) decl
  91 #  endif /* __GNUC__ >= 2 */
  92 # endif /* SM_UNUSED */
  93
  94 /*
  95 **  The SM_NONVOLATILE macro is used to declare variables that are not
  96 **  volatile, but which must be declared volatile when compiling with
  97 **  gcc -O -Wall in order to suppress bogus warning messages.
  98 **
  99 **  Variables that actually are volatile should be declared volatile
 100 **  using the "volatile" keyword.  If a variable actually is volatile,
 101 **  then SM_NONVOLATILE should not be used.
 102 **
 103 **  To compile sendmail with gcc and see all non-bogus warnings,
 104 **  you should use
 105 **      gcc -O -Wall -DSM_OMIT_BOGUS_WARNINGS ...
 106 **  Do not use -DSM_OMIT_BOGUS_WARNINGS when compiling the production
 107 **  version of sendmail, because there is a performance hit.
 108 */
 109
 110 # ifdef SM_OMIT_BOGUS_WARNINGS
 111 #  define SM_NONVOLATILE volatile
 112 # else /* SM_OMIT_BOGUS_WARNINGS */
 113 #  define SM_NONVOLATILE
 114 # endif /* SM_OMIT_BOGUS_WARNINGS */
 115
 116 /*
 117 **  Turn on format string argument checking.
 118 */
 119
 120 # ifndef SM_CONF_FORMAT_TEST
 121 #  if __GNUC__ == 2 && __GNUC_MINOR__ >= 7
 122 #   define SM_CONF_FORMAT_TEST  1
 123 #  else /* __GNUC__ == 2 && __GNUC_MINOR__ >= 7 */
 124 #   define SM_CONF_FORMAT_TEST  0
 125 #  endif /* __GNUC__ == 2 && __GNUC_MINOR__ >= 7 */
 126 # endif /* SM_CONF_FORMAT_TEST */
 127
 128 # ifndef PRINTFLIKE
 129 #  if SM_CONF_FORMAT_TEST
 130 #   define PRINTFLIKE(x,y) __attribute__ ((__format__ (__printf__, x, y)))
 131 #  else /* SM_CONF_FORMAT_TEST */
 132 #   define PRINTFLIKE(x,y)
 133 #  endif /* SM_CONF_FORMAT_TEST */
 134 # endif /* ! PRINTFLIKE */
 135
 136 # ifndef SCANFLIKE
 137 #  if SM_CONF_FORMAT_TEST
 138 #   define SCANFLIKE(x,y) __attribute__ ((__format__ (__scanf__, x, y)))
 139 #  else /* SM_CONF_FORMAT_TEST */
 140 #   define SCANFLIKE(x,y)
 141 #  endif /* SM_CONF_FORMAT_TEST */
 142 # endif /* ! SCANFLIKE */
 143
 144 #endif /* ! SM_CDEFS_H */