main.c

生成C++的词法/语法分析的Flex语法分析器

/* flex - tool to generate fast lexical analyzers */

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Vern Paxson.
 * 
 * The United States Government has rights in this work pursuant
 * to contract no. DE-AC03-76SF00098 between the United States
 * Department of Energy and the University of California.
 *
 * Redistribution and use in source and binary forms are permitted provided
 * that: (1) source distributions retain this entire copyright notice and
 * comment, and (2) distributions including binaries display the following
 * acknowledgement:  ``This product includes software developed by the
 * University of California, Berkeley and its contributors'' in the
 * documentation or other materials provided with the distribution and in
 * all advertising materials mentioning features or use of this software.
 * Neither the name of the University nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1990 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char rcsid[] =
    "@(#) $Header: /usr/fsys/odin/a/vern/flex/RCS/main.c,v 2.9 90/06/27 23:48:24 vern Exp $ (LBL)";
#endif


#include "flexdef.h"

static char flex_version[] = "2.3.8-7 (flex++), based on 2.3.8 and modified by [e-mail] for c++";

/* declare functions that have forward references */

void flexinit PROTO((int, char**));
void readin PROTO(());
void set_up_initial_allocations PROTO(());


/* these globals are all defined and commented in flexdef.h */
int printstats, syntaxerror, eofseen, ddebug, trace, spprdflt;
int interactive, caseins, useecs, fulltbl, usemecs;
int fullspd, gen_line_dirs, performance_report, backtrack_report, csize;
int yymore_used, reject, real_reject, continued_action;
int yymore_really_used, reject_really_used;
int datapos, dataline, linenum;
FILE *skelfile = NULL;
char *infilename = NULL;
char *headerfilename=NULL;
FILE *headerfile=NULL;
char *outputfilename=NULL;
char *includefilename=NULL;
char *skelheaderfilename=NULL;
FILE *skelheaderfile=NULL;
int onestate[ONE_STACK_SIZE], onesym[ONE_STACK_SIZE];
int onenext[ONE_STACK_SIZE], onedef[ONE_STACK_SIZE], onesp;
int current_mns, num_rules, current_max_rules, lastnfa;
int *firstst, *lastst, *finalst, *transchar, *trans1, *trans2;
int *accptnum, *assoc_rule, *state_type, *rule_type, *rule_linenum;
int current_state_type;
int variable_trailing_context_rules;
int numtemps, numprots, protprev[MSP], protnext[MSP], prottbl[MSP];
int protcomst[MSP], firstprot, lastprot, protsave[PROT_SAVE_SIZE];
int numecs, nextecm[CSIZE + 1], ecgroup[CSIZE + 1], nummecs, tecfwd[CSIZE + 1];
int tecbck[CSIZE + 1];
int *xlation = (int *) 0;
int num_xlations;
int lastsc, current_max_scs, *scset, *scbol, *scxclu, *sceof, *actvsc;
char **scname;
int current_max_dfa_size, current_max_xpairs;
int current_max_template_xpairs, current_max_dfas;
int lastdfa, *nxt, *chk, *tnxt;
int *base, *def, *nultrans, NUL_ec, tblend, firstfree, **dss, *dfasiz;
union dfaacc_union *dfaacc;
int *accsiz, *dhash, numas;
int numsnpairs, jambase, jamstate;
int lastccl, current_maxccls, *cclmap, *ccllen, *cclng, cclreuse;
int current_max_ccl_tbl_size;
Char *ccltbl;
char *starttime, *endtime, nmstr[MAXLINE];
int sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs;
int tmpuses, totnst, peakpairs, numuniq, numdup, hshsave;
int num_backtracking, bol_needed;
FILE *temp_action_file;
FILE *backtrack_file;
int end_of_buffer_state;
char *action_file_name = NULL;
char **input_files;
int num_input_files;
char *program_name;
char lexer_name[256]="lex";
int name_defined=0;
char *skelname = NULL;

#ifndef SHORT_FILE_NAMES
static char *outfile = "lex.yy.c";
#else
static char *outfile = "lexyy.c";
#endif
static int outfile_created = 0;
static int use_stdout;
/* suffixes recognised to convert C/C++ outputfilename to headerfilename */
static char *c_suffixes[]=
   {".c",".cc",".cpp",".cxx",".C",".CPP",".CXX",".CC",(char *)0};


int main( argc, argv )
int argc;
char **argv;

    {
    flexinit( argc, argv );

    readin();

    if ( syntaxerror )
	flexend( 1 );

    if ( yymore_really_used == REALLY_USED )
	yymore_used = true;
    else if ( yymore_really_used == REALLY_NOT_USED )
	yymore_used = false;

    if ( reject_really_used == REALLY_USED )
	reject = true;
    else if ( reject_really_used == REALLY_NOT_USED )
	reject = false;

    if ( performance_report )
	{
	if ( interactive )
	    fprintf( stderr,
		     "-I (interactive) entails a minor performance penalty\n" );

	if ( yymore_used )
	    fprintf( stderr, "yymore() entails a minor performance penalty\n" );

	if ( reject )
	    fprintf( stderr, "REJECT entails a large performance penalty\n" );

	if ( variable_trailing_context_rules )
	    fprintf( stderr,
"Variable trailing context rules entail a large performance penalty\n" );
	}

    if ( reject )
	real_reject = true;

    if ( variable_trailing_context_rules )
	reject = true;

    if ( (fulltbl || fullspd) && reject )
	{
	if ( real_reject )
	    flexerror( "REJECT cannot be used with -f or -F" );
	else
	    flexerror(
	"variable trailing context rules cannot be used with -f or -F" );
	}

    ntod();

    /* generate the C state transition tables from the DFA */
    make_tables();

    /* note, flexend does not return.  It exits with its argument as status. */

    flexend( 0 );

    /*NOTREACHED*/
    }


/* flexend - terminate flex
 *
 * synopsis
 *    int status;
 *    flexend( status );
 *
 *    status is exit status.
 *
 * note
 *    This routine does not return.
 */

void flexend( status )
int status;

    {
    int tblsiz;
    char *flex_gettime();

    if ( skelfile != NULL )
	{
	if ( ferror( skelfile ) )
	    flexfatal( "error occurred when writing skeleton file" );

	else if ( fclose( skelfile ) )
	    flexfatal( "error occurred when closing skeleton file" );
	}

    if ( skelheaderfile != NULL )
	{
	if ( ferror( skelheaderfile ) )
	    flexfatal( "error occurred when writing header skeleton file" );

	else if ( fclose( skelheaderfile ) )
	    flexfatal( "error occurred when closing haeder skeleton file" );
	}

    if ( temp_action_file )
	{
	if ( ferror( temp_action_file ) )
	    flexfatal( "error occurred when writing temporary action file" );

	else if ( fclose( temp_action_file ) )
	    flexfatal( "error occurred when closing temporary action file" );

	else if ( unlink( action_file_name ) )
	    flexfatal( "error occurred when deleting temporary action file" );
	}
    else if ( headerfile  )
	{
	if ( ferror( headerfile ) )
	    flexfatal( "error occurred when writing header file" );

	else if ( fclose( headerfile ) )
	    flexfatal( "error occurred when closing header file" );

	else if ( unlink( action_file_name ) )
	    flexfatal( "error occurred when deleting temporary action file" );
	}

    if ( status != 0 && outfile_created )
	{
	if ( ferror( stdout ) )
	    flexfatal( "error occurred when writing output file" );

	else if ( fclose( stdout ) )
	    flexfatal( "error occurred when closing output file" );

	else if ( unlink( outfile ) )
	    flexfatal( "error occurred when deleting output file" );
	}

    if ( backtrack_report && backtrack_file )
	{
	if ( num_backtracking == 0 )
	    fprintf( backtrack_file, "No backtracking.\n" );
	else if ( fullspd || fulltbl )
	    fprintf( backtrack_file,
		     "%d backtracking (non-accepting) states.\n",
		     num_backtracking );
	else
	    fprintf( backtrack_file, "Compressed tables always backtrack.\n" );

	if ( ferror( backtrack_file ) )
	    flexfatal( "error occurred when writing backtracking file" );

	else if ( fclose( backtrack_file ) )
	    flexfatal( "error occurred when closing backtracking file" );
	}

    if ( printstats )
	{
	endtime = flex_gettime();

	fprintf( stderr, "%s version %s usage statistics:\n", program_name,
		 flex_version );
	fprintf( stderr, "  started at %s, finished at %s\n",
		 starttime, endtime );

	fprintf( stderr, "  scanner options: -" );

	if ( backtrack_report )
	    putc( 'b', stderr );
	if ( ddebug )
	    putc( 'd', stderr );
	if ( interactive )
	    putc( 'I', stderr );
	if ( caseins )
	    putc( 'i', stderr );
	if ( ! gen_line_dirs )
	    putc( 'L', stderr );
	if ( performance_report )
	    putc( 'p', stderr );
	if ( spprdflt )
	    putc( 's', stderr );
	if ( use_stdout )
	    putc( 't', stderr );
	if ( trace )
	    putc( 'T', stderr );
	if ( printstats )
	    putc( 'v', stderr );        /* always true! */
	if ( csize == 256 )
	    putc( '8', stderr );

	fprintf( stderr, " -C" );

	if ( fulltbl )
	    putc( 'f', stderr );
	if ( fullspd )
	    putc( 'F', stderr );
	if ( useecs )
	    putc( 'e', stderr );
	if ( usemecs )
	    putc( 'm', stderr );

	if ( outputfilename )
	    fprintf( stderr, " -o%s", outputfilename );

	if ( headerfilename )
	    fprintf( stderr, " -h%s", headerfilename );

	if ( includefilename && headerfilename && 
	     ! strcmp(includefilename,headerfilename ))
	    fprintf( stderr, " -g%s", includefilename );
	    
	if ( skelname && strcmp( skelname, DEFAULT_SKELETON_FILE ) )
	    fprintf( stderr, " -S%s", skelname );

	if ( strcmp( skelname, DEFAULT_SKELETONHEADER_FILE ) )
	    fprintf( stderr, " -H%s", skelheaderfilename );

	putc( '\n', stderr );

	fprintf( stderr, "  %d/%d NFA states\n", lastnfa, current_mns );
	fprintf( stderr, "  %d/%d DFA states (%d words)\n", lastdfa,
		 current_max_dfas, totnst );
	fprintf( stderr,
		 "  %d rules\n", num_rules - 1 /* - 1 for def. rule */ );

	if ( num_backtracking == 0 )
	    fprintf( stderr, "  No backtracking\n" );
	else if ( fullspd || fulltbl )
	    fprintf( stderr, "  %d backtracking (non-accepting) states\n",
		     num_backtracking );
	else
	    fprintf( stderr, "  compressed tables always backtrack\n" );

	if ( bol_needed )
	    fprintf( stderr, "  Beginning-of-line patterns used\n" );

	fprintf( stderr, "  %d/%d start conditions\n", lastsc,
		 current_max_scs );
	fprintf( stderr, "  %d epsilon states, %d double epsilon states\n",
		 numeps, eps2 );

	if ( lastccl == 0 )
	    fprintf( stderr, "  no character classes\n" );
	else
	    fprintf( stderr,
	"  %d/%d character classes needed %d/%d words of storage, %d reused\n",
		     lastccl, current_maxccls,
		     cclmap[lastccl] + ccllen[lastccl],
		     current_max_ccl_tbl_size, cclreuse );

	fprintf( stderr, "  %d state/nextstate pairs created\n", numsnpairs );
	fprintf( stderr, "  %d/%d unique/duplicate transitions\n",
		 numuniq, numdup );

	if ( fulltbl )
	    {
	    tblsiz = lastdfa * numecs;
	    fprintf( stderr, "  %d table entries\n", tblsiz );
	    }

	else
	    {
	    tblsiz = 2 * (lastdfa + numtemps) + 2 * tblend;

	    fprintf( stderr, "  %d/%d base-def entries created\n",
		     lastdfa + numtemps, current_max_dfas );
	    fprintf( stderr, "  %d/%d (peak %d) nxt-chk entries created\n",
		     tblend, current_max_xpairs, peakpairs );
	    fprintf( stderr,
		     "  %d/%d (peak %d) template nxt-chk entries created\n",
		     numtemps * nummecs, current_max_template_xpairs,
		     numtemps * numecs );
	    fprintf( stderr, "  %d empty table entries\n", nummt );
	    fprintf( stderr, "  %d protos created\n", numprots );
	    fprintf( stderr, "  %d templates created, %d uses\n",
		     numtemps, tmpuses );
	    }

	if ( useecs )
	    {
	    tblsiz = tblsiz + csize;
	    fprintf( stderr, "  %d/%d equivalence classes created\n",
		     numecs, csize );
	    }

	if ( usemecs )
	    {
	    tblsiz = tblsiz + numecs;
	    fprintf( stderr, "  %d/%d meta-equivalence classes created\n",
		     nummecs, csize );
	    }

	fprintf( stderr, "  %d (%d saved) hash collisions, %d DFAs equal\n",
		 hshcol, hshsave, dfaeql );
	fprintf( stderr, "  %d sets of reallocations needed\n", num_reallocs );
	fprintf( stderr, "  %d total table entries needed\n", tblsiz );
	}

#ifndef VMS
    exit( status );
#else
    exit( status + 1 );
#endif
    }


/* flexinit - initialize flex
 *
 * synopsis
 *    int argc;
 *    char **argv;
 *    flexinit( argc, argv );
 */

void flexinit( argc, argv )
int argc;
char **argv;

    {
    int i, sawcmpflag;
    char *arg, *flex_gettime(), *mktemp();
	char *tmp_action=(char *)0;
    printstats = syntaxerror = trace = spprdflt = interactive = caseins = false;
    backtrack_report = performance_report = ddebug = fulltbl = fullspd = false;
    yymore_used = continued_action = reject = false;
    yymore_really_used = reject_really_used = false;
    gen_line_dirs = usemecs = useecs = true;

    sawcmpflag = false;
    use_stdout = false;

    csize = DEFAULT_CSIZE;
    starttime = flex_gettime();

    program_name = argv[0];

    /* read flags */
    for ( --argc, ++argv; argc ; --argc, ++argv )
	{
	if ( argv[0][0] != '-' || argv[0][1] == '\0' )
	    break;

	arg = argv[0];

	for ( i = 1; arg[i] != '\0'; ++i )
	    switch ( arg[i] )
		{
		case 'a':
		    if ( i != 1 )
			flexerror( "-a flag must be given separately" );
		    tmp_action = &arg[i+1];
		    goto get_next_arg;
		case 'b':
		    backtrack_report = true;
		    break;

		case 'c':
		    fprintf( stderr,
	"%s: Assuming use of deprecated -c flag is really intended to be -C\n",
			     program_name );

		    /* fall through */

		case 'C':
		    if ( i != 1 )
			flexerror( "-C flag must be given separately" );

		    if ( ! sawcmpflag )
			{
			useecs = false;
			usemecs = false;
			fulltbl = false;
			sawcmpflag = true;
			}