src/flex-scanner.h

   1 /* Common parts between scan-code.l, scan-gram.l, and scan-skel.l.
   2
   3    Copyright (C) 2006, 2009, 2010 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 /* Pacify "gcc -Wmissing-prototypes" when flex 2.5.31 is used.  */
  25 int   FLEX_PREFIX (get_lineno) (void);
  26 FILE *FLEX_PREFIX (get_in) (void);
  27 FILE *FLEX_PREFIX (get_out) (void);
  28 int   FLEX_PREFIX (get_leng) (void);
  29 char *FLEX_PREFIX (get_text) (void);
  30 void  FLEX_PREFIX (set_lineno) (int);
  31 void  FLEX_PREFIX (set_in) (FILE *);
  32 void  FLEX_PREFIX (set_out) (FILE *);
  33 int   FLEX_PREFIX (get_debug) (void);
  34 void  FLEX_PREFIX (set_debug) (int);
  35 int   FLEX_PREFIX (lex_destroy) (void);
  36
  37 #define last_string    FLEX_PREFIX (last_string)
  38
  39 /* It seems to be a nice "feature" of Flex that one cannot use yytext,
  40    yyleng etc. when a prefix is given, since there is no longer a
  41    #define, but rather the token is actually changed in the output.
  42    However, this is not true for Flex 2.5.4.  */
  43 #ifndef yyleng
  44 # define yyleng  FLEX_PREFIX (leng)
  45 #endif
  46 #ifndef yytext
  47 # define yytext  FLEX_PREFIX (text)
  48 #endif
  49
  50 /* Non-reentrant scanners generated by Flex 2.5.9 and later (and some earlier
  51    versions according to the Flex manual) leak memory if yylex_destroy is not
  52    invoked.  However, yylex_destroy is not defined before Flex 2.5.9, so give
  53    an implementation here that at least appears to work with Flex 2.5.4.  */
  54 #if !defined(YY_FLEX_MAJOR_VERSION) || YY_FLEX_MAJOR_VERSION < 2 \
  55     || (YY_FLEX_MAJOR_VERSION == 2 \
  56         && (!defined(YY_FLEX_MINOR_VERSION) || YY_FLEX_MINOR_VERSION < 5 \
  57             || (YY_FLEX_MINOR_VERSION == 5 \
  58                 && (!defined(YY_FLEX_SUBMINOR_VERSION) \
  59                     || YY_FLEX_SUBMINOR_VERSION < 9))))
  60 # define yylex_destroy() yy_delete_buffer (YY_CURRENT_BUFFER)
  61 #endif
  62
  63 /* OBSTACK_FOR_STRING -- Used to store all the characters that we need to
  64    keep (to construct ID, STRINGS etc.).  Use the following macros to
  65    use it.
  66
  67    Use STRING_GROW to append what has just been matched, and
  68    STRING_FINISH to end the string (it puts the ending 0).
  69    STRING_FINISH also stores this string in LAST_STRING, which can be
  70    used, and which is used by STRING_FREE to free the last string.  */
  71
  72 #ifndef FLEX_NO_OBSTACK
  73
  74 static struct obstack obstack_for_string;
  75
  76 #define STRING_GROW   \
  77   obstack_grow (&obstack_for_string, yytext, yyleng)
  78
  79 #define STRING_FINISH                                   \
  80   do {                                                  \
  81     obstack_1grow (&obstack_for_string, '\0');          \
  82     last_string = obstack_finish (&obstack_for_string); \
  83   } while (0)
  84
  85 #define STRING_FREE \
  86   obstack_free (&obstack_for_string, last_string)
  87
  88 #endif