src/system.h

   1 /* System-dependent definitions for Bison.
   2
   3    Copyright (C) 2000-2007, 2009-2015, 2018-2020 Free Software
   4    Foundation, Inc.
   5
   6    This program is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation, either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program 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
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef BISON_SYSTEM_H
  20 # define BISON_SYSTEM_H
  21
  22 /* flex 2.5.31 gratuitously defines macros like INT8_MIN.  But this
  23    runs afoul of pre-C99 compilers that have <inttypes.h> or
  24    <stdint.h>, which are included below if available.  It also runs
  25    afoul of pre-C99 compilers that define these macros in <limits.h>.  */
  26 # if ! defined __STDC_VERSION__ || __STDC_VERSION__ < 199901
  27 #  undef INT8_MIN
  28 #  undef INT16_MIN
  29 #  undef INT32_MIN
  30 #  undef INT8_MAX
  31 #  undef INT16_MAX
  32 #  undef UINT8_MAX
  33 #  undef INT32_MAX
  34 #  undef UINT16_MAX
  35 #  undef UINT32_MAX
  36 # endif
  37
  38 # include <limits.h>
  39 # include <stddef.h>
  40 # include <stdlib.h>
  41 # include <string.h>
  42
  43 # define ARRAY_CARDINALITY(Array) (sizeof (Array) / sizeof *(Array))
  44 # define STREQ(L, R)  (strcmp(L, R) == 0)
  45 # define STRNEQ(L, R) (!STREQ(L, R))
  46
  47 /* Just like strncmp, but the second argument must be a literal string
  48    and you don't specify the length.  */
  49 # define STRNCMP_LIT(S, Literal)                        \
  50   strncmp (S, "" Literal "", sizeof (Literal) - 1)
  51
  52 /* Whether Literal is a prefix of S.  */
  53 # define STRPREFIX_LIT(Literal, S)              \
  54   (STRNCMP_LIT (S, Literal) == 0)
  55
  56 # include <unistd.h>
  57 # include <inttypes.h>
  58
  59 # ifndef UINTPTR_MAX
  60 /* This isn't perfect, but it's good enough for Bison, which needs
  61    only to hash pointers.  */
  62 typedef size_t uintptr_t;
  63 # endif
  64
  65 /* Version mismatch. */
  66 # define EX_MISMATCH 63
  67
  68 /*---------.
  69 | Gnulib.  |
  70 `---------*/
  71
  72 # include <unlocked-io.h>
  73 # include <verify.h>
  74 # include <xalloc.h>
  75
  76 // Clang and ICC like to pretend they are GCC.
  77 # if defined __GNUC__ && !defined __clang__ && !defined __ICC
  78 #  define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
  79 # endif
  80
  81 // See https://lists.gnu.org/archive/html/bug-bison/2019-10/msg00061.html
  82 // and https://trac.macports.org/ticket/59927.
  83 # if defined GCC_VERSION && 405 <= GCC_VERSION
  84 #  define IGNORE_TYPE_LIMITS_BEGIN \
  85      _Pragma ("GCC diagnostic push") \
  86      _Pragma ("GCC diagnostic ignored \"-Wtype-limits\"")
  87 #  define IGNORE_TYPE_LIMITS_END \
  88      _Pragma ("GCC diagnostic pop")
  89 # else
  90 #  define IGNORE_TYPE_LIMITS_BEGIN
  91 #  define IGNORE_TYPE_LIMITS_END
  92 # endif
  93
  94
  95 /*-----------------.
  96 | GCC extensions.  |
  97 `-----------------*/
  98
  99 /* Use PACIFY_CC to indicate that Code is unimportant to the logic of Bison
 100    but that it is necessary for suppressing compiler warnings.  For example,
 101    Code might be a variable initializer that's always overwritten before the
 102    variable is used.
 103
 104    PACIFY_CC is intended to be useful only as a comment as it does not alter
 105    Code.  It is tempting to redefine PACIFY_CC so that it will suppress Code
 106    when configuring without --enable-gcc-warnings.  However, that would mean
 107    that, for maintainers, Bison would compile with potentially less warnings
 108    and safer logic than it would for users.  Due to the overhead of M4,
 109    suppressing Code is unlikely to offer any significant improvement in
 110    Bison's performance anyway.  */
 111 # define PACIFY_CC(Code) Code
 112
 113 # include <attribute.h>
 114
 115
 116 /*------.
 117 | NLS.  |
 118 `------*/
 119
 120 # include <locale.h>
 121
 122 # include <gettext.h>
 123 # define _(Msgid)  gettext (Msgid)
 124 # define N_(Msgid) (Msgid)
 125
 126
 127 /*-----------.
 128 | Booleans.  |
 129 `-----------*/
 130
 131 # include <stdbool.h>
 132
 133
 134
 135 /*-------------.
 136 | Assertions.  |
 137 `-------------*/
 138
 139 /* In the past, Bison defined aver to simply invoke abort in the case of
 140    a failed assertion.  The rationale was that <assert.h>'s assertions
 141    were too heavyweight and could be disabled too easily.  See
 142    discussions at
 143    <http://lists.gnu.org/archive/html/bison-patches/2006-01/msg00080.html>
 144    <http://lists.gnu.org/archive/html/bison-patches/2006-09/msg00111.html>.
 145
 146    However, normal assert output can be helpful during development and
 147    in bug reports from users.  Moreover, it's not clear now that
 148    <assert.h>'s assertions are significantly heavyweight.  Finally, if
 149    users want to experiment with disabling assertions, it's debatable
 150    whether it's our responsibility to stop them.  See discussion
 151    starting at
 152    <http://lists.gnu.org/archive/html/bison-patches/2009-09/msg00013.html>.
 153
 154    For now, we use assert but we call it aver throughout Bison in case
 155    we later wish to try another scheme.
 156 */
 157 # include <assert.h>
 158 # define aver assert
 159
 160
 161 /*-----------.
 162 | Obstacks.  |
 163 `-----------*/
 164
 165 # define obstack_chunk_alloc xmalloc
 166 # define obstack_chunk_free  free
 167 # include <obstack.h>
 168
 169 /* String-grow: append Str to Obs.  */
 170
 171 # define obstack_sgrow(Obs, Str) \
 172   obstack_grow (Obs, Str, strlen (Str))
 173
 174 /* Output Str escaped to be a string.
 175
 176    For instance "\"foo\"" -> "\\\"foo\\\"".  */
 177
 178 # define obstack_backslash(Obs, Str)                    \
 179   do {                                                  \
 180     char const *p__;                                    \
 181     for (p__ = Str; *p__; p__++)                        \
 182       switch (*p__)                                     \
 183         {                                               \
 184         case '"':  obstack_sgrow (Obs, "\\\""); break;  \
 185         case '\\': obstack_sgrow (Obs, "\\\\"); break;  \
 186         default:   obstack_1grow (Obs, *p__);   break;  \
 187         }                                               \
 188   } while (0)
 189
 190
 191 /* Output Str escaped for our postprocessing (i.e., escape M4 special
 192    characters).
 193
 194    For instance "[foo]" -> "@{foo@}", "$$" -> "$][$][". */
 195
 196 # define obstack_escape(Obs, Str)                       \
 197   do {                                                  \
 198     char const *p__;                                    \
 199     for (p__ = Str; *p__; p__++)                        \
 200       switch (*p__)                                     \
 201         {                                               \
 202         case '$': obstack_sgrow (Obs, "$]["); break;    \
 203         case '@': obstack_sgrow (Obs, "@@" ); break;    \
 204         case '[': obstack_sgrow (Obs, "@{" ); break;    \
 205         case ']': obstack_sgrow (Obs, "@}" ); break;    \
 206         default:  obstack_1grow (Obs, *p__ ); break;    \
 207         }                                               \
 208   } while (0)
 209
 210
 211 /* Output Str both quoted for M4 (i.e., embed in [[...]]), and escaped
 212    for our postprocessing (i.e., escape M4 special characters).  If
 213    Str is empty (or NULL), output "[]" instead of "[[]]" as it makes
 214    M4 programming easier (m4_ifval can be used).
 215
 216    For instance "[foo]" -> "[[@{foo@}]]", "$$" -> "[[$][$][]]".  */
 217
 218 # define obstack_quote(Obs, Str)                \
 219   do {                                          \
 220     char const* obstack_quote_p = Str;          \
 221     if (obstack_quote_p && obstack_quote_p[0])  \
 222       {                                         \
 223         obstack_sgrow (Obs, "[[");              \
 224         obstack_escape (Obs, obstack_quote_p);  \
 225         obstack_sgrow (Obs, "]]");              \
 226       }                                         \
 227     else                                        \
 228       obstack_sgrow (Obs, "[]");                \
 229   } while (0)
 230
 231
 232 /* Append the ending 0, finish Obs, and return the string.  */
 233
 234 # define obstack_finish0(Obs)                                   \
 235   (obstack_1grow (Obs, '\0'), (char *) obstack_finish (Obs))
 236
 237
 238 /*-----------------------------------------.
 239 | Extensions to use for the output files.  |
 240 `-----------------------------------------*/
 241
 242 # ifndef OUTPUT_EXT
 243 #  define OUTPUT_EXT ".output"
 244 # endif
 245
 246 # ifndef TAB_EXT
 247 #  define TAB_EXT ".tab"
 248 # endif
 249
 250
 251
 252 /*---------------------.
 253 | Free a linked list.  |
 254 `---------------------*/
 255
 256 # define LIST_FREE(Type, List)                  \
 257   do {                                          \
 258     Type *_node, *_next;                        \
 259     for (_node = List; _node; _node = _next)    \
 260       {                                         \
 261         _next = _node->next;                    \
 262         free (_node);                           \
 263       }                                         \
 264   } while (0)
 265
 266 #endif  /* ! BISON_SYSTEM_H */