src/main.c

   1 /* Top level entry point of bison,
   2    Copyright 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 #include "print_graph.h"
  37 #include "symtab.h"
  38
  39 /* The name this program was run with, for messages.  */
  40 char *program_name;
  41
  42 extern void berror PARAMS((const char *));
  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   open_files ();
  56
  57   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  58      and FATTRS.  In file reader.c.  The other parts are recorded in
  59      the grammar; see gram.h.  */
  60   reader ();
  61   if (complain_message_count)
  62     exit (1);
  63
  64   /* find useless nonterminals and productions and reduce the grammar.  In
  65      file reduce.c */
  66   reduce_grammar ();
  67
  68   /* record other info about the grammar.  In files derives and nullable.  */
  69   set_derives ();
  70   set_nullable ();
  71
  72   /* convert to nondeterministic finite state machine.  In file LR0.
  73      See state.h for more info.  */
  74   generate_states ();
  75
  76   /* make it deterministic.  In file lalr.  */
  77   lalr ();
  78
  79   /* Find and record any conflicts: places where one token of
  80      lookahead is not enough to disambiguate the parsing.  In file
  81      conflicts.  Also resolve s/r conflicts based on precedence
  82      declarations.  */
  83   solve_conflicts ();
  84
  85   /* Output file names. */
  86   compute_output_file_names ();
  87
  88   /* Stop if there were errors, to avoid trashing previous output
  89      files.  */
  90   if (complain_message_count)
  91     exit (1);
  92
  93   /* Print information about results, if requested.  */
  94   print_results ();
  95
  96   /* Output the VCG graph. */
  97   print_graph ();
  98
  99   /* Output the tables and the parser to ftable.  In file output.  */
 100   output ();
 101
 102   /* Free the symbol table data structure.  */
 103   free_symtab ();
 104
 105   /* Close the input files. */
 106   close_files ();
 107
 108   free_conflicts ();
 109   free_nullable ();
 110   free_derives ();
 111
 112   output_files ();
 113
 114   exit (complain_message_count ? 1 : 0);
 115 }
 116 \f
 117 /* Abort for an internal error denoted by string S.  */
 118
 119 void
 120 berror (const char *s)
 121 {
 122   fprintf (stderr, _("%s: internal error: %s\n"), program_name, s);
 123   abort ();
 124 }