www.pudn.com > bison.zip > main.c

/* Top level entry point of bison, 
   Copyright (C) 1984, 1986, 1989 Free Software Foundation, Inc. 
 
This file is part of Bison, the GNU Compiler Compiler. 
 
Bison is free software; you can redistribute it and/or modify 
it under the terms of the GNU General Public License as published by 
the Free Software Foundation; either version 2, or (at your option) 
any later version. 
 
Bison is distributed in the hope that it will be useful, 
but WITHOUT ANY WARRANTY; without even the implied warranty of 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
GNU General Public License for more details. 
 
You should have received a copy of the GNU General Public License 
along with Bison; see the file COPYING.  If not, write to 
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */ 
 
 
#include  
#include "system.h" 
#include "machine.h"	/* JF for MAXSHORT */ 
 
extern	int lineno; 
extern	int verboseflag; 
 
/* Nonzero means failure has been detected; don't write a parser file.  */ 
int failure; 
 
/* The name this program was run with, for messages. */ 
char *program_name; 
 
extern void getargs(), openfiles(), reader(), reduce_grammar(); 
extern void set_derives(), set_nullable(), generate_states(); 
extern void lalr(), initialize_conflicts(), verbose(), terse(); 
extern void output(), done(); 
 
 
/* VMS complained about using `int'.  */ 
int 
main(argc, argv) 
int argc; 
char *argv[]; 
{ 
  program_name = argv[0]; 
  failure = 0; 
  lineno = 0; 
  getargs(argc, argv); 
  openfiles(); 
 
  /* read the input.  Copy some parts of it to fguard, faction, ftable and fattrs. 
     In file reader.c. 
     The other parts are recorded in the grammar; see gram.h.  */ 
  reader(); 
 
  /* find useless nonterminals and productions and reduce the grammar.  In 
     file reduce.c */ 
  reduce_grammar(); 
 
  /* record other info about the grammar.  In files derives and nullable.  */ 
  set_derives(); 
  set_nullable(); 
 
  /* convert to nondeterministic finite state machine.  In file LR0. 
     See state.h for more info.  */ 
  generate_states(); 
 
  /* make it deterministic.  In file lalr.  */ 
  lalr(); 
 
  /* Find and record any conflicts: places where one token of lookahead is not 
     enough to disambiguate the parsing.  In file conflicts. 
     Also resolve s/r conflicts based on precedence declarations.  */ 
  initialize_conflicts(); 
 
  /* print information about results, if requested.  In file print. */ 
  if (verboseflag) 
    verbose(); 
  else 
    terse(); 
 
  /* output the tables and the parser to ftable.  In file output. */ 
  output(); 
  done(failure); 
} 
 
/* functions to report errors which prevent a parser from being generated */ 
 
void 
fatal(s) 
char *s; 
{ 
  extern char *infile; 
 
  if (infile == 0) 
    fprintf(stderr, "fatal error: %s\n", s); 
  else 
    fprintf(stderr, "\"%s\", line %d: %s\n", infile, lineno, s); 
  done(1); 
} 
 
 
/* JF changed to accept/deal with variable args. 
   DO NOT change this to use varargs.  It will appear to work 
   but will break on systems that don't have the necessary library 
   functions.  This is the ONLY safe way to write such a function.  */ 
/*VARARGS1*/ 
 
void 
fatals(fmt,x1,x2,x3,x4,x5,x6,x7,x8) 
char *fmt; 
{ 
  char buffer[200]; 
 
  sprintf(buffer, fmt, x1,x2,x3,x4,x5,x6,x7,x8); 
  fatal(buffer); 
} 
 
 
void 
toomany(s) 
char *s; 
{ 
  char buffer[200]; 
 
	/* JF new msg */ 
  sprintf(buffer, "limit of %d exceeded, too many %s", MAXSHORT, s); 
  fatal(buffer); 
} 
 
 
void 
berror(s) 
char *s; 
{ 
  fprintf(stderr, "internal error, %s\n", s); 
  abort(); 
}