src/system.h

   1 /* System-dependent definitions for Bison.
   2
   3    Copyright (C) 2000-2007, 2009-2012 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 3 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
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #ifndef BISON_SYSTEM_H
  19 # define BISON_SYSTEM_H
  20
  21 /* flex 2.5.31 gratutiously defines macros like INT8_MIN.  But this
  22    runs afoul of pre-C99 compilers that have <inttypes.h> or
  23    <stdint.h>, which are included below if available.  It also runs
  24    afoul of pre-C99 compilers that define these macros in <limits.h>.  */
  25 # if ! defined __STDC_VERSION__ || __STDC_VERSION__ < 199901
  26 #  undef INT8_MIN
  27 #  undef INT16_MIN
  28 #  undef INT32_MIN
  29 #  undef INT8_MAX
  30 #  undef INT16_MAX
  31 #  undef UINT8_MAX
  32 #  undef INT32_MAX
  33 #  undef UINT16_MAX
  34 #  undef UINT32_MAX
  35 # endif
  36
  37 # include <limits.h>
  38 # include <stddef.h>
  39 # include <stdlib.h>
  40 # include <string.h>
  41 # include <unistd.h>
  42 # include <inttypes.h>
  43
  44 # ifndef UINTPTR_MAX
  45 /* This isn't perfect, but it's good enough for Bison, which needs
  46    only to hash pointers.  */
  47 typedef size_t uintptr_t;
  48 # endif
  49
  50 // Version mismatch.
  51 # define EX_MISMATCH 63
  52
  53 /*---------.
  54 | Gnulib.  |
  55 `---------*/
  56
  57 # include <unlocked-io.h>
  58 # include <verify.h>
  59 # include <xalloc.h>
  60
  61
  62 /*-----------------.
  63 | GCC extensions.  |
  64 `-----------------*/
  65
  66 /* Use PACIFY_CC to indicate that Code is unimportant to the logic of Bison
  67    but that it is necessary for suppressing compiler warnings.  For example,
  68    Code might be a variable initializer that's always overwritten before the
  69    variable is used.
  70
  71    PACIFY_CC is intended to be useful only as a comment as it does not alter
  72    Code.  It is tempting to redefine PACIFY_CC so that it will suppress Code
  73    when configuring without --enable-gcc-warnings.  However, that would mean
  74    that, for maintainers, Bison would compile with potentially less warnings
  75    and safer logic than it would for users.  Due to the overhead of M4,
  76    suppressing Code is unlikely to offer any significant improvement in
  77    Bison's performance anyway.  */
  78 # define PACIFY_CC(Code) Code
  79
  80 # ifndef __attribute__
  81 /* This feature is available in gcc versions 2.5 and later.  */
  82 #  if (! defined __GNUC__ || __GNUC__ < 2 \
  83        || (__GNUC__ == 2 && __GNUC_MINOR__ < 5))
  84 #   define __attribute__(Spec) /* empty */
  85 #  endif
  86 # endif
  87
  88 /* The __-protected variants of `format' and `printf' attributes
  89    are accepted by gcc versions 2.6.4 (effectively 2.7) and later.  */
  90 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7)
  91 #  define __format__ format
  92 #  define __printf__ printf
  93 # endif
  94
  95 # ifndef ATTRIBUTE_NORETURN
  96 #  define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
  97 # endif
  98
  99 # ifndef ATTRIBUTE_UNUSED
 100 #  define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
 101 # endif
 102
 103
 104 /*------.
 105 | NLS.  |
 106 `------*/
 107
 108 # include <locale.h>
 109
 110 # include <gettext.h>
 111 # define _(Msgid)  gettext (Msgid)
 112 # define N_(Msgid) (Msgid)
 113
 114
 115 /*-----------.
 116 | Booleans.  |
 117 `-----------*/
 118
 119 # include <stdbool.h>
 120
 121
 122
 123 /*-------------.
 124 | Assertions.  |
 125 `-------------*/
 126
 127 /* In the past, Bison defined aver to simply invoke abort in the case of
 128    a failed assertion.  The rationale was that <assert.h>'s assertions
 129    were too heavyweight and could be disabled too easily.  See
 130    discussions at
 131    <http://lists.gnu.org/archive/html/bison-patches/2006-01/msg00080.html>
 132    <http://lists.gnu.org/archive/html/bison-patches/2006-09/msg00111.html>.
 133
 134    However, normal assert output can be helpful during development and
 135    in bug reports from users.  Moreover, it's not clear now that
 136    <assert.h>'s assertions are significantly heavyweight.  Finally, if
 137    users want to experiment with disabling assertions, it's debatable
 138    whether it's our responsibility to stop them.  See discussion
 139    starting at
 140    <http://lists.gnu.org/archive/html/bison-patches/2009-09/msg00013.html>.
 141
 142    For now, we use assert but we call it aver throughout Bison in case
 143    we later wish to try another scheme.
 144 */
 145 # include <assert.h>
 146 # define aver assert
 147
 148
 149 /*-----------.
 150 | Obstacks.  |
 151 `-----------*/
 152
 153 # define obstack_chunk_alloc xmalloc
 154 # define obstack_chunk_free  free
 155 # include <obstack.h>
 156
 157 # define obstack_sgrow(Obs, Str)                \
 158   obstack_grow (Obs, Str, strlen (Str))
 159
 160 /* Output Str escaped for our postprocessing (i.e., escape M4 special
 161    characters).
 162
 163    For instance "[foo]" -> "@{foo@}", "$$" -> "$][$][". */
 164
 165 # define obstack_escape(Obs, Str)                       \
 166   do {                                                  \
 167     char const *p;                                      \
 168     for (p = Str; *p; p++)                              \
 169       switch (*p)                                       \
 170         {                                               \
 171         case '$': obstack_sgrow (Obs, "$]["); break;    \
 172         case '@': obstack_sgrow (Obs, "@@" ); break;    \
 173         case '[': obstack_sgrow (Obs, "@{" ); break;    \
 174         case ']': obstack_sgrow (Obs, "@}" ); break;    \
 175         default:  obstack_1grow (Obs, *p   ); break;    \
 176         }                                               \
 177   } while (0)
 178
 179
 180 /* Output Str both quoted for M4 (i.e., embed in [[...]]), and escaped
 181    for our postprocessing (i.e., escape M4 special characters).  If
 182    Str is empty (or NULL), output "[]" instead of "[[]]" as it make M4
 183    programming easier (m4_ifval can be used).
 184
 185    For instance "[foo]" -> "[[@{foo@}]]", "$$" -> "[[$][$][]]". */
 186
 187 # define obstack_quote(Obs, Str)                \
 188   do {                                          \
 189     char const* obstack_quote_p = Str;          \
 190     if (obstack_quote_p && obstack_quote_p[0])  \
 191       {                                         \
 192         obstack_sgrow (Obs, "[[");              \
 193         obstack_escape (Obs, obstack_quote_p);  \
 194         obstack_sgrow (Obs, "]]");              \
 195       }                                         \
 196     else                                        \
 197       obstack_sgrow (Obs, "[]");                \
 198   } while (0)
 199
 200
 201
 202
 203
 204 /*-----------------------------------------.
 205 | Extensions to use for the output files.  |
 206 `-----------------------------------------*/
 207
 208 # ifndef OUTPUT_EXT
 209 #  define OUTPUT_EXT ".output"
 210 # endif
 211
 212 # ifndef TAB_EXT
 213 #  define TAB_EXT ".tab"
 214 # endif
 215
 216
 217
 218 /*---------------------.
 219 | Free a linked list.  |
 220 `---------------------*/
 221
 222 # define LIST_FREE(Type, List)                  \
 223   do {                                          \
 224     Type *_node, *_next;                        \
 225     for (_node = List; _node; _node = _next)    \
 226       {                                         \
 227         _next = _node->next;                    \
 228         free (_node);                           \
 229       }                                         \
 230   } while (0)
 231
 232
 233 /*---------------------------------------------.
 234 | Debugging memory allocation (must be last).  |
 235 `---------------------------------------------*/
 236
 237 # if WITH_DMALLOC
 238 #  define DMALLOC_FUNC_CHECK
 239 #  include <dmalloc.h>
 240 # endif /* WITH_DMALLOC */
 241
 242 #endif  /* ! BISON_SYSTEM_H */