src/main.c

   1 /* Top level entry point of bison,
   2    Copyright (C) 1984, 1986, 1989, 1992, 1995, 2000
   3    Free Software Foundation, Inc.
   4
   5    This file is part of Bison, the GNU Compiler Compiler.
   6
   7    Bison 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 2, or (at your option)
  10    any later version.
  11
  12    Bison 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 Bison; see the file COPYING.  If not, write to
  19    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22
  23 #include "system.h"
  24 #include "getargs.h"
  25 #include "files.h"
  26 #include "complain.h"
  27 #include "derives.h"
  28 #include "output.h"
  29 #include "reader.h"
  30 #include "lalr.h"
  31 #include "reduce.h"
  32 #include "nullable.h"
  33 #include "print.h"
  34 #include "LR0.h"
  35 #include "conflicts.h"
  36
  37 /* The name this program was run with, for messages.  */
  38 char *program_name;
  39
  40 extern void berror PARAMS((const char *));
  41
  42 extern char *printable_version PARAMS ((int));
  43
  44 int
  45 main (int argc, char *argv[])
  46 {
  47   program_name = argv[0];
  48   setlocale (LC_ALL, "");
  49   bindtextdomain (PACKAGE, LOCALEDIR);
  50   textdomain (PACKAGE);
  51
  52   lineno = 0;
  53   getargs (argc, argv);
  54
  55   /* Be ready to clean up if we exit. */
  56   atexit (done);
  57
  58   open_files ();
  59
  60   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  61      and FATTRS.  In file reader.c.  The other parts are recorded in
  62      the grammar; see gram.h.  */
  63   reader ();
  64   if (complain_message_count)
  65     exit (1);
  66
  67   /* find useless nonterminals and productions and reduce the grammar.  In
  68      file reduce.c */
  69   reduce_grammar ();
  70
  71   /* record other info about the grammar.  In files derives and nullable.  */
  72   set_derives ();
  73   set_nullable ();
  74
  75   /* convert to nondeterministic finite state machine.  In file LR0.
  76      See state.h for more info.  */
  77   generate_states ();
  78
  79   /* make it deterministic.  In file lalr.  */
  80   lalr ();
  81
  82   /* Find and record any conflicts: places where one token of
  83      lookahead is not enough to disambiguate the parsing.  In file
  84      conflicts.  Also resolve s/r conflicts based on precedence
  85      declarations.  */
  86   initialize_conflicts ();
  87
  88   /* Print information about results, if requested.  */
  89   print_results ();
  90
  91   /* Output the tables and the parser to ftable.  In file output.  */
  92   output ();
  93
  94   finalize_conflicts ();
  95   free_nullable ();
  96   free_derives ();
  97
  98   exit (complain_message_count ? 1 : 0);
  99 }
 100 \f
 101 /* Return a string containing a printable version of C:
 102    either C itself, or the corresponding \DDD code.  */
 103
 104 char *
 105 printable_version (int c)
 106 {
 107   static char buf[10];
 108   if (c < ' ' || c >= '\177')
 109     sprintf (buf, "\\%o", c);
 110   else
 111     {
 112       buf[0] = c;
 113       buf[1] = '\0';
 114     }
 115   return buf;
 116 }
 117
 118 /* Abort for an internal error denoted by string S.  */
 119
 120 void
 121 berror (const char *s)
 122 {
 123   fprintf (stderr, _("%s: internal error: %s\n"), program_name, s);
 124   abort ();
 125 }