src/flex-scanner.h

   1 /* Common parts between scan-code.l, scan-gram.l, and scan-skel.l.
   2
   3    Copyright (C) 2006, 2009-2012 Free Software Foundation, Inc.
   4
   5    This file is part of Bison, the GNU Compiler Compiler.
   6
   7    This program is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef FLEX_PREFIX
  21 # error "FLEX_PREFIX not defined"
  22 #endif
  23
  24 /* Whether this version of Flex is (strictly) greater than
  25    Major.Minor.Subminor.  */
  26 #define FLEX_VERSION_GT(Major, Minor, Subminor)                         \
  27   (defined YY_FLEX_MAJOR_VERSION                                        \
  28    && (Major < YY_FLEX_MAJOR_VERSION                                    \
  29        || (Major == YY_FLEX_MAJOR_VERSION                               \
  30            && (defined YY_FLEX_MINOR_VERSION                            \
  31                && (Minor < YY_FLEX_MINOR_VERSION                        \
  32                    || (Minor == YY_FLEX_MINOR_VERSION                   \
  33                        && defined YY_FLEX_SUBMINOR_VERSION              \
  34                        && Subminor < YY_FLEX_SUBMINOR_VERSION))))))
  35
  36 /* Pacify "gcc -Wmissing-prototypes" when flex 2.5.31 is used.  */
  37 # if ! FLEX_VERSION_GT (2, 5, 31)
  38 int   FLEX_PREFIX (get_lineno) (void);
  39 FILE *FLEX_PREFIX (get_in) (void);
  40 FILE *FLEX_PREFIX (get_out) (void);
  41 int   FLEX_PREFIX (get_leng) (void);
  42 char *FLEX_PREFIX (get_text) (void);
  43 void  FLEX_PREFIX (set_lineno) (int);
  44 void  FLEX_PREFIX (set_in) (FILE *);
  45 void  FLEX_PREFIX (set_out) (FILE *);
  46 int   FLEX_PREFIX (get_debug) (void);
  47 void  FLEX_PREFIX (set_debug) (int);
  48 int   FLEX_PREFIX (lex_destroy) (void);
  49 #endif
  50
  51 #define last_string    FLEX_PREFIX (last_string)
  52
  53 /* It seems to be a nice "feature" of Flex that one cannot use yytext,
  54    yyleng etc. when a prefix is given, since there is no longer a
  55    #define, but rather the token is actually changed in the output.
  56    However, this is not true for Flex 2.5.4.  */
  57 #ifndef yyleng
  58 # define yyleng  FLEX_PREFIX (leng)
  59 #endif
  60 #ifndef yytext
  61 # define yytext  FLEX_PREFIX (text)
  62 #endif
  63
  64 /* Non-reentrant scanners generated by Flex 2.5.9 and later (and some earlier
  65    versions according to the Flex manual) leak memory if yylex_destroy is not
  66    invoked.  However, yylex_destroy is not defined before Flex 2.5.9, so give
  67    an implementation here that at least appears to work with Flex 2.5.4.  */
  68 #if ! FLEX_VERSION_GT (2, 5, 9)
  69 # define yylex_destroy() yy_delete_buffer (YY_CURRENT_BUFFER)
  70 #endif
  71
  72 /* OBSTACK_FOR_STRING -- Used to store all the characters that we need to
  73    keep (to construct ID, STRINGS etc.).  Use the following macros to
  74    use it.
  75
  76    Use STRING_GROW to append what has just been matched, and
  77    STRING_FINISH to end the string (it puts the ending 0).
  78    STRING_FINISH also stores this string in LAST_STRING, which can be
  79    used, and which is used by STRING_FREE to free the last string.  */
  80
  81 #ifndef FLEX_NO_OBSTACK
  82
  83 static struct obstack obstack_for_string;
  84
  85 # define STRING_GROW   \
  86   obstack_grow (&obstack_for_string, yytext, yyleng)
  87
  88 # define STRING_FINISH                                  \
  89   do {                                                  \
  90     obstack_1grow (&obstack_for_string, '\0');          \
  91     last_string = obstack_finish (&obstack_for_string); \
  92   } while (0)
  93
  94 # define STRING_FREE \
  95   obstack_free (&obstack_for_string, last_string)
  96
  97 #endif