src/main.c

   1 /* Top level entry point of bison,
   2    Copyright 1984, 1986, 1989, 1992, 1995, 2000, 2001, 2002
   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 "bitset.h"
  25 #include "getargs.h"
  26 #include "files.h"
  27 #include "complain.h"
  28 #include "derives.h"
  29 #include "output.h"
  30 #include "reader.h"
  31 #include "lalr.h"
  32 #include "reduce.h"
  33 #include "nullable.h"
  34 #include "print.h"
  35 #include "LR0.h"
  36 #include "conflicts.h"
  37 #include "print_graph.h"
  38 #include "muscle_tab.h"
  39 #include "symtab.h"
  40 #include "lex.h"
  41
  42 /* The name this program was run with, for messages.  */
  43 char *program_name;
  44
  45 int
  46 main (int argc, char *argv[])
  47 {
  48   program_name = argv[0];
  49   setlocale (LC_ALL, "");
  50   bindtextdomain (PACKAGE, LOCALEDIR);
  51   textdomain (PACKAGE);
  52
  53   lineno = 0;
  54   getargs (argc, argv);
  55
  56   muscle_init ();
  57
  58   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  59      and FATTRS.  In file reader.c.  The other parts are recorded in
  60      the grammar; see gram.h.  */
  61   reader ();
  62   if (complain_message_count)
  63     exit (1);
  64
  65   /* Find useless nonterminals and productions and reduce the grammar. */
  66   reduce_grammar ();
  67
  68   /* Record other info about the grammar.  In files derives and
  69      nullable.  */
  70   set_derives ();
  71   set_nullable ();
  72
  73   /* Convert to nondeterministic finite state machine.  In file LR0.
  74      See state.h for more info.  */
  75   generate_states ();
  76
  77   /* make it deterministic.  In file lalr.  */
  78   lalr ();
  79
  80   /* Find and record any conflicts: places where one token of
  81      lookahead is not enough to disambiguate the parsing.  In file
  82      conflicts.  Also resolve s/r conflicts based on precedence
  83      declarations.  */
  84   solve_conflicts ();
  85   conflicts_print ();
  86
  87   /* Output file names. */
  88   compute_output_file_names ();
  89
  90   /* Output the detailed report on the grammar.  */
  91   if (verbose_flag)
  92     print_results ();
  93
  94   /* Stop if there were errors, to avoid trashing previous output
  95      files.  */
  96   if (complain_message_count)
  97     exit (1);
  98
  99   /* Output the VCG graph.  */
 100   if (graph_flag)
 101     print_graph ();
 102
 103   /* Output the tables and the parser to ftable.  In file output.  */
 104   output ();
 105
 106   /* Free the symbol table data structure.  */
 107   free_symtab ();
 108
 109   reduce_free ();
 110   free_conflicts ();
 111   free_nullable ();
 112   free_derives ();
 113
 114   /* If using alloca.c, flush the alloca'ed memory for the benefit of
 115      people running Bison as a library in IDEs.  */
 116 #if C_ALLOCA
 117     alloca (0);
 118 #endif
 119
 120   return complain_message_count ? EXIT_FAILURE : EXIT_SUCCESS;
 121 }