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   1 /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
   2 /*
   3  * Copyright (c) 1993, 1994, 1995, 1996, 1997
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. All advertising materials mentioning features or use of this software
  15  *    must display the following acknowledgement:
  16  *      This product includes software developed by the Computer Systems
  17  *      Engineering Group at Lawrence Berkeley Laboratory.
  18  * 4. Neither the name of the University nor of the Laboratory may be used
  19  *    to endorse or promote products derived from this software without
  20  *    specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #ifndef lib_pcap_compiler_tests_h
  36 #define lib_pcap_compiler_tests_h
  37
  38
  39 /*
  40  * This was introduced by Clang:
  41  *
  42  *     http://clang.llvm.org/docs/LanguageExtensions.html#has-attribute
  43  *
  44  * in some version (which version?); it has been picked up by GCC 5.0.
  45  */
  46 #ifndef __has_attribute
  47   /*
  48    * It's a macro, so you can check whether it's defined to check
  49    * whether it's supported.
  50    *
  51    * If it's not, define it to always return 0, so that we move on to
  52    * the fallback checks.
  53    */
  54   #define __has_attribute(x) 0
  55 #endif
  56
  57 /*
  58  * Note that the C90 spec's "6.8.1 Conditional inclusion" and the
  59  * C99 spec's and C11 spec's "6.10.1 Conditional inclusion" say:
  60  *
  61  *    Prior to evaluation, macro invocations in the list of preprocessing
  62  *    tokens that will become the controlling constant expression are
  63  *    replaced (except for those macro names modified by the defined unary
  64  *    operator), just as in normal text.  If the token "defined" is
  65  *    generated as a result of this replacement process or use of the
  66  *    "defined" unary operator does not match one of the two specified
  67  *    forms prior to macro replacement, the behavior is undefined.
  68  *
  69  * so you shouldn't use defined() in a #define that's used in #if or
  70  * #elif.  Some versions of Clang, for example, will warn about this.
  71  *
  72  * Instead, we check whether the pre-defined macros for particular
  73  * compilers are defined and, if not, define the "is this version XXX
  74  * or a later version of this compiler" macros as 0.
  75  */
  76
  77 /*
  78  * Check whether this is GCC major.minor or a later release, or some
  79  * compiler that claims to be "just like GCC" of that version or a
  80  * later release.
  81  */
  82
  83 #if ! defined(__GNUC__)
  84 #define PCAP_IS_AT_LEAST_GNUC_VERSION(major, minor) 0
  85 #else
  86 #define PCAP_IS_AT_LEAST_GNUC_VERSION(major, minor) \
  87         (__GNUC__ > (major) || \
  88          (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
  89 #endif
  90
  91 /*
  92  * Check whether this is Sun C/SunPro C/Oracle Studio major.minor
  93  * or a later release.
  94  *
  95  * The version number in __SUNPRO_C is encoded in hex BCD, with the
  96  * uppermost hex digit being the major version number, the next
  97  * one or two hex digits being the minor version number, and
  98  * the last digit being the patch version.
  99  *
 100  * It represents the *compiler* version, not the product version;
 101  * see
 102  *
 103  *    https://sourceforge.net/p/predef/wiki/Compilers/
 104  *
 105  * for a partial mapping, which we assume continues for later
 106  * 12.x product releases.
 107  */
 108
 109 #if ! defined(__SUNPRO_C)
 110 #define PCAP_IS_AT_LEAST_SUNC_VERSION(major,minor) 0
 111 #else
 112 #define PCAP_SUNPRO_VERSION_TO_BCD(major, minor) \
 113         (((minor) >= 10) ? \
 114             (((major) << 12) | (((minor)/10) << 8) | (((minor)%10) << 4)) : \
 115             (((major) << 8) | ((minor) << 4)))
 116 #define PCAP_IS_AT_LEAST_SUNC_VERSION(major,minor) \
 117         (__SUNPRO_C >= PCAP_SUNPRO_VERSION_TO_BCD((major), (minor)))
 118 #endif
 119
 120 /*
 121  * Check whether this is IBM XL C major.minor or a later release.
 122  *
 123  * The version number in __xlC__ has the major version in the
 124  * upper 8 bits and the minor version in the lower 8 bits.
 125  */
 126
 127 #if ! defined(__xlC__)
 128 #define PCAP_IS_AT_LEAST_XL_C_VERSION(major,minor) 0
 129 #else
 130 #define PCAP_IS_AT_LEAST_XL_C_VERSION(major, minor) \
 131         (__xlC__ >= (((major) << 8) | (minor)))
 132 #endif
 133
 134 /*
 135  * Check whether this is HP aC++/HP C major.minor or a later release.
 136  *
 137  * The version number in __HP_aCC is encoded in zero-padded decimal BCD,
 138  * with the "A." stripped off, the uppermost two decimal digits being
 139  * the major version number, the next two decimal digits being the minor
 140  * version number, and the last two decimal digits being the patch version.
 141  * (Strip off the A., remove the . between the major and minor version
 142  * number, and add two digits of patch.)
 143  */
 144
 145 #if ! defined(__HP_aCC)
 146 #define PCAP_IS_AT_LEAST_HP_C_VERSION(major,minor) 0
 147 #else
 148 #define PCAP_IS_AT_LEAST_HP_C_VERSION(major,minor) \
 149         (__HP_aCC >= ((major)*10000 + (minor)*100))
 150 #endif
 151
 152 #endif /* lib_pcap_funcattrs_h */