src/common/tuklib_common.h

   1 // SPDX-License-Identifier: 0BSD
   2
   3 ///////////////////////////////////////////////////////////////////////////////
   4 //
   5 /// \file       tuklib_common.h
   6 /// \brief      Common definitions for tuklib modules
   7 //
   8 //  Author:     Lasse Collin
   9 //
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef TUKLIB_COMMON_H
  13 #define TUKLIB_COMMON_H
  14
  15 // The config file may be replaced by a package-specific file.
  16 // It should include at least stddef.h, stdbool.h, inttypes.h, and limits.h.
  17 #include "tuklib_config.h"
  18
  19 // TUKLIB_SYMBOL_PREFIX is prefixed to all symbols exported by
  20 // the tuklib modules. If you use a tuklib module in a library,
  21 // you should use TUKLIB_SYMBOL_PREFIX to make sure that there
  22 // are no symbol conflicts in case someone links your library
  23 // into application that also uses the same tuklib module.
  24 #ifndef TUKLIB_SYMBOL_PREFIX
  25 #       define TUKLIB_SYMBOL_PREFIX
  26 #endif
  27
  28 #define TUKLIB_CAT_X(a, b) a ## b
  29 #define TUKLIB_CAT(a, b) TUKLIB_CAT_X(a, b)
  30
  31 #ifndef TUKLIB_SYMBOL
  32 #       define TUKLIB_SYMBOL(sym) TUKLIB_CAT(TUKLIB_SYMBOL_PREFIX, sym)
  33 #endif
  34
  35 #ifndef TUKLIB_DECLS_BEGIN
  36 #       ifdef __cplusplus
  37 #               define TUKLIB_DECLS_BEGIN extern "C" {
  38 #       else
  39 #               define TUKLIB_DECLS_BEGIN
  40 #       endif
  41 #endif
  42
  43 #ifndef TUKLIB_DECLS_END
  44 #       ifdef __cplusplus
  45 #               define TUKLIB_DECLS_END }
  46 #       else
  47 #               define TUKLIB_DECLS_END
  48 #       endif
  49 #endif
  50
  51 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
  52 #       define TUKLIB_GNUC_REQ(major, minor) \
  53                 ((__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)) \
  54                         || __GNUC__ > (major))
  55 #else
  56 #       define TUKLIB_GNUC_REQ(major, minor) 0
  57 #endif
  58
  59 // tuklib_attr_noreturn attribute is used to mark functions as non-returning.
  60 // We cannot use "noreturn" as the macro name because then C23 code that
  61 // uses [[noreturn]] would break as it would expand to [[ [[noreturn]] ]].
  62 //
  63 // tuklib_attr_noreturn must be used at the beginning of function declaration
  64 // to work in all cases. The [[noreturn]] syntax is the most limiting, it
  65 // must be even before any GNU C's __attribute__ keywords:
  66 //
  67 //     tuklib_attr_noreturn
  68 //     __attribute__((nonnull(1)))
  69 //     extern void foo(const char *s);
  70 //
  71 // FIXME: Update __STDC_VERSION__ for the final C23 version. 202000 is used
  72 // by GCC 13 and Clang 15 with -std=c2x.
  73 #if   defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202000
  74 #       define tuklib_attr_noreturn [[noreturn]]
  75 #elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112
  76 #       define tuklib_attr_noreturn _Noreturn
  77 #elif TUKLIB_GNUC_REQ(2, 5)
  78 #       define tuklib_attr_noreturn __attribute__((__noreturn__))
  79 #elif defined(_MSC_VER)
  80 #       define tuklib_attr_noreturn __declspec(noreturn)
  81 #else
  82 #       define tuklib_attr_noreturn
  83 #endif
  84
  85 #if (defined(_WIN32) && !defined(__CYGWIN__)) \
  86                 || defined(__OS2__) || defined(__MSDOS__)
  87 #       define TUKLIB_DOSLIKE 1
  88 #endif
  89
  90 #endif