libmicrohttpd2

HTTP server C library (MHD 2.x, alpha)
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mhd_align.h (5944B)


      1 /* SPDX-License-Identifier: LGPL-2.1-or-later OR (GPL-2.0-or-later WITH eCos-exception-2.0) */
      2 /*
      3   This file is part of GNU libmicrohttpd.
      4   Copyright (C) 2021-2022 Karlson2k (Evgeny Grin)
      5 
      6   GNU libmicrohttpd is free software; you can redistribute it and/or
      7   modify it under the terms of the GNU Lesser General Public
      8   License as published by the Free Software Foundation; either
      9   version 2.1 of the License, or (at your option) any later version.
     10 
     11   GNU libmicrohttpd is distributed in the hope that it will be useful,
     12   but WITHOUT ANY WARRANTY; without even the implied warranty of
     13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14   Lesser General Public License for more details.
     15 
     16   Alternatively, you can redistribute GNU libmicrohttpd and/or
     17   modify it under the terms of the GNU General Public License as
     18   published by the Free Software Foundation; either version 2 of
     19   the License, or (at your option) any later version, together
     20   with the eCos exception, as follows:
     21 
     22     As a special exception, if other files instantiate templates or
     23     use macros or inline functions from this file, or you compile this
     24     file and link it with other works to produce a work based on this
     25     file, this file does not by itself cause the resulting work to be
     26     covered by the GNU General Public License. However the source code
     27     for this file must still be made available in accordance with
     28     section (3) of the GNU General Public License v2.
     29 
     30     This exception does not invalidate any other reasons why a work
     31     based on this file might be covered by the GNU General Public
     32     License.
     33 
     34   You should have received copies of the GNU Lesser General Public
     35   License and the GNU General Public License along with this library;
     36   if not, see <https://www.gnu.org/licenses/>.
     37 */
     38 
     39 /**
     40  * @file src/mhd2/mhd_align.h
     41  * @brief  types alignment macros
     42  * @author Karlson2k (Evgeny Grin)
     43  */
     44 
     45 #ifndef MHD_ALIGN_H
     46 #define MHD_ALIGN_H 1
     47 
     48 #include "mhd_sys_options.h"
     49 
     50 #include "sys_base_types.h"
     51 
     52 #if (defined(__GNUC__) && __GNUC__ < 4 && __GNUC_MINOR__ < 9 && \
     53   ! defined(__clang__)) || \
     54   (defined(__clang__) && __clang_major__ < 8) || \
     55   (defined(__clang__) && __clang_major__ < 11 && \
     56   defined(__apple_build_version__))
     57 /* GCC before 4.9 and clang before 8.0 have incorrect implementation of 'alignof()'
     58    which returns preferred alignment instead of minimal required alignment */
     59 #  define mhd_SYS_ALIGNOF_UNRELIABLE 1
     60 #elif defined(_MSC_VER) && ! defined(__clang__) && _MSC_VER < 1900
     61 /* MSVC has the same problem as old GCC versions:
     62    '__alignof()' may return "preferred" alignment instead of "required". */
     63 #  define mhd_SYS_ALIGNOF_UNRELIABLE 1
     64 #endif /* _MSC_VER < 1900 */
     65 
     66 #ifndef mhd_ALIGNOF
     67 #  ifndef mhd_SYS_ALIGNOF_UNRELIABLE
     68 #    ifdef HAVE_C_ALIGNOF
     69 #      if ! defined(__STDC_VERSION__) || (__STDC_VERSION__ + 0) < 202311
     70 #        ifdef HAVE_STDALIGN_H
     71 #          include <stdalign.h>
     72 #        endif /* HAVE_STDALIGN_H */
     73 #      endif
     74 #      if defined(alignof) || defined(__alignof_is_defined) || \
     75   (defined(__STDC_VERSION__) && (__STDC_VERSION__ + 0) >= 202311)
     76 #        define mhd_ALIGNOF(TYPE) alignof(TYPE)
     77 #      endif
     78 #    endif /* HAVE_C_ALIGNOF */
     79 
     80 #    ifndef mhd_ALIGNOF
     81 #      if defined(_MSC_VER) && ! defined(__clang__) && _MSC_VER >= 1700
     82 #        define mhd_ALIGNOF(TYPE) __alignof (TYPE)
     83 #      endif /* _MSC_VER >= 1700 */
     84 #    endif /* !mhd_ALIGNOF */
     85 #  endif
     86 #endif
     87 
     88 #ifndef mhd_ALIGNOF
     89 #  include "sys_offsetof.h"
     90 #  define mhd_ALIGNOF(TYPE) \
     91         offsetof (struct { char mhd__s; TYPE mhd__m; }, mhd__m)
     92 #endif
     93 
     94 /* Provide a limited set of alignment macros */
     95 /* The set could be extended as needed */
     96 #define mhd_UINT32_ALIGN mhd_ALIGNOF (uint_least32_t)
     97 #define mhd_UINT64_ALIGN mhd_ALIGNOF (uint_least32_t)
     98 #define mhd_UINT_FAST32_ALIGN mhd_ALIGNOF (uint_fast32_t)
     99 
    100 
    101 #if defined(HAVE_ATTR_ALIGNED)
    102 #  define mhd_ALIGNED(num)      __attribute__((aligned (num)))
    103 #elif defined(HAVE_DECLSPEC_ALIGN)
    104 #  define mhd_ALIGNED(num)      __declspec(align (num)))
    105 #endif
    106 
    107 #ifdef HAVE_C_ALIGNAS
    108 #  if ! defined(__STDC_VERSION__) || (__STDC_VERSION__ + 0) < 202311
    109 #    ifdef HAVE_STDALIGN_H
    110 #      include <stdalign.h>
    111 #    endif /* HAVE_STDALIGN_H */
    112 #  endif /* before C23 */
    113 #  if defined(alignas) || defined(__alignas_is_defined) || \
    114   (defined(__STDC_VERSION__) && (__STDC_VERSION__ + 0) >= 202311)
    115 #    define mhd_ALIGNED_AS(type)      alignas (type)
    116 #    ifndef mhd_ALIGNED
    117 #      define mhd_ALIGNED(num)        alignas (num)
    118 #    endif /* ! mhd_ALIGNED */
    119 #  endif /* alignas || C23 or later */
    120 #endif /* ! HAVE_C_ALIGNAS */
    121 
    122 #ifndef mhd_ALIGNED
    123 #  define mhd_ALIGNED(num)      /* Empty fallback */
    124 #endif
    125 
    126 #ifndef mhd_ALIGNED_AS
    127 #  define mhd_ALIGNED_AS(type)          mhd_ALIGNED (mhd_ALIGNOF (type))
    128 #endif
    129 
    130 #if defined(MHD_ALIGNMENT_LARGE_NUM) && (MHD_ALIGNMENT_LARGE_NUM + 0) >= 8
    131 #  define mhd_ALIGNED_8         mhd_ALIGNED (8)
    132 #else
    133 #  define mhd_ALIGNED_8         mhd_ALIGNED_AS (void*)
    134 #endif
    135 
    136 #if defined(MHD_ALIGNMENT_LARGE_NUM) && (MHD_ALIGNMENT_LARGE_NUM + 0) >= 16
    137 #  define mhd_ALIGNED_16        mhd_ALIGNED (16)
    138 #else
    139 #  define mhd_ALIGNED_16        mhd_ALIGNED_8
    140 #endif
    141 
    142 #if defined(MHD_ALIGNMENT_LARGE_NUM) && (MHD_ALIGNMENT_LARGE_NUM + 0) >= 32
    143 #  define mhd_ALIGNED_32        mhd_ALIGNED (32)
    144 #else
    145 #  define mhd_ALIGNED_32        mhd_ALIGNED_16
    146 #endif
    147 
    148 #if defined(MHD_ALIGNMENT_LARGE_NUM) && (MHD_ALIGNMENT_LARGE_NUM + 0) >= 64
    149 #  define mhd_ALIGNED_64        mhd_ALIGNED (64)
    150 #else
    151 #  define mhd_ALIGNED_64        mhd_ALIGNED_32
    152 #endif
    153 
    154 #if defined(MHD_ALIGNMENT_LARGE_NUM) && (MHD_ALIGNMENT_LARGE_NUM + 0) >= 128
    155 #  define mhd_ALIGNED_128       mhd_ALIGNED (128)
    156 #else
    157 #  define mhd_ALIGNED_128       mhd_ALIGNED_64
    158 #endif
    159 
    160 #if defined(MHD_ALIGNMENT_LARGE_NUM) && (MHD_ALIGNMENT_LARGE_NUM + 0) >= 256
    161 #  define mhd_ALIGNED_256       mhd_ALIGNED (256)
    162 #else
    163 #  define mhd_ALIGNED_256       mhd_ALIGNED_128
    164 #endif
    165 
    166 #endif /* ! MHD_ALIGN_H */