main.c

flex编译器的源代码

/* 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 */

/* $Header: /home/daffy/u0/vern/flex/RCS/main.c,v 2.63 95/04/20 13:53:23 vern Exp $ */


#include "flexdef.h"
#include "version.h"

static char flex_version[] = FLEX_VERSION;


/* declare functions that have forward references */

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

#ifdef NEED_ARGV_FIXUP
extern void argv_fixup PROTO((int *, char ***));
#endif


/* these globals are all defined and commented in flexdef.h */
int printstats, syntaxerror, eofseen, ddebug, trace, nowarn, spprdflt;
int interactive, caseins, lex_compat, do_yylineno, useecs, fulltbl, usemecs;
int fullspd, gen_line_dirs, performance_report, backing_up_report;
int C_plus_plus, long_align, use_read, yytext_is_array, do_yywrap, csize;
int yymore_used, reject, real_reject, continued_action, in_rule;
int yymore_really_used, reject_really_used;
int datapos, dataline, linenum, out_linenum;
FILE *skelfile = NULL;
int skel_ind = 0;
char *action_array;
int action_size, defs1_offset, prolog_offset, action_offset, action_index;
char *infilename = NULL, *outfilename = NULL;
int did_outfilename;
char *prefix, *yyclass;
int do_stdinit, use_stdout;
int onestate[ONE_STACK_SIZE], onesym[ONE_STACK_SIZE];
int onenext[ONE_STACK_SIZE], onedef[ONE_STACK_SIZE], onesp;
int current_mns, current_max_rules;
int num_rules, num_eof_rules, default_rule, lastnfa;
int *firstst, *lastst, *finalst, *transchar, *trans1, *trans2;
int *accptnum, *assoc_rule, *state_type;
int *rule_type, *rule_linenum, *rule_useful;
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 lastsc, *scset, *scbol, *scxclu, *sceof;
int current_max_scs;
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, *cclmap, *ccllen, *cclng, cclreuse;
int current_maxccls, current_max_ccl_tbl_size;
Char *ccltbl;
char nmstr[MAXLINE];
int sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs;
int tmpuses, totnst, peakpairs, numuniq, numdup, hshsave;
int num_backing_up, bol_needed;
FILE *backing_up_file;
int end_of_buffer_state;
char **input_files;
int num_input_files;

/* Make sure program_name is initialized so we don't crash if writing
 * out an error message before getting the program name from argv[0].
 */
char *program_name = "flex";

#ifndef SHORT_FILE_NAMES
static char *outfile_template = "lex.%s.%s";
static char *backing_name = "lex.backup";
#else
static char *outfile_template = "lex%s.%s";
static char *backing_name = "lex.bck";
#endif

#ifdef THINK_C
#include <console.h>
#endif

#ifdef MS_DOS
extern unsigned _stklen = 16384;
#endif

static char outfile_path[MAXLINE];
static int outfile_created = 0;
static char *skelname = NULL;


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

#ifdef THINK_C
	argc = ccommand( &argv );
#endif
#ifdef NEED_ARGV_FIXUP
	argv_fixup( &argc, &argv );
#endif

	flexinit( argc, argv );

	readin();

	ntod();

	for ( i = 1; i <= num_rules; ++i )
		if ( ! rule_useful[i] && i != default_rule )
			line_warning( _( "rule cannot be matched" ),
					rule_linenum[i] );

	if ( spprdflt && ! reject && rule_useful[default_rule] )
		line_warning(
			_( "-s option given but default rule can be matched" ),
			rule_linenum[default_rule] );

	/* 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 );

	return 0;	/* keep compilers/lint happy */
	}


/* check_options - check user-specified options */

void check_options()
	{
	int i;

	if ( lex_compat )
		{
		if ( C_plus_plus )
			flexerror( _( "Can't use -+ with -l option" ) );

		if ( fulltbl || fullspd )
			flexerror( _( "Can't use -f or -F with -l option" ) );

		/* Don't rely on detecting use of yymore() and REJECT,
		 * just assume they'll be used.
		 */
		yymore_really_used = reject_really_used = true;

		yytext_is_array = true;
		do_yylineno = true;
		use_read = false;
		}

	if ( do_yylineno )
		/* This should really be "maintain_backup_tables = true" */
		reject_really_used = true;

	if ( csize == unspecified )
		{
		if ( (fulltbl || fullspd) && ! useecs )
			csize = DEFAULT_CSIZE;
		else
			csize = CSIZE;
		}

	if ( interactive == unspecified )
		{
		if ( fulltbl || fullspd )
			interactive = false;
		else
			interactive = true;
		}

	if ( fulltbl || fullspd )
		{
		if ( usemecs )
			flexerror(
			_( "-Cf/-CF and -Cm don't make sense together" ) );

		if ( interactive )
			flexerror( _( "-Cf/-CF and -I are incompatible" ) );

		if ( lex_compat )
			flexerror(
		_( "-Cf/-CF are incompatible with lex-compatibility mode" ) );

		if ( do_yylineno )
			flexerror(
			_( "-Cf/-CF and %option yylineno are incompatible" ) );

		if ( fulltbl && fullspd )
			flexerror( _( "-Cf and -CF are mutually exclusive" ) );
		}

	if ( C_plus_plus && fullspd )
		flexerror( _( "Can't use -+ with -CF option" ) );

	if ( C_plus_plus && yytext_is_array )
		{
		warn( _( "%array incompatible with -+ option" ) );
		yytext_is_array = false;
		}

	if ( useecs )
		{ /* Set up doubly-linked equivalence classes. */

		/* We loop all the way up to csize, since ecgroup[csize] is
		 * the position used for NUL characters.
		 */
		ecgroup[1] = NIL;

		for ( i = 2; i <= csize; ++i )
			{
			ecgroup[i] = i - 1;
			nextecm[i - 1] = i;
			}

		nextecm[csize] = NIL;
		}

	else
		{
		/* Put everything in its own equivalence class. */
		for ( i = 1; i <= csize; ++i )
			{
			ecgroup[i] = i;
			nextecm[i] = BAD_SUBSCRIPT;	/* to catch errors */
			}
		}

	if ( ! use_stdout )
		{
		FILE *prev_stdout;

		if ( ! did_outfilename )
			{
			char *suffix;

			if ( C_plus_plus )
				suffix = "cc";
			else
				suffix = "c";

			sprintf( outfile_path, outfile_template,
				prefix, suffix );

			outfilename = outfile_path;
			}

		prev_stdout = freopen( outfilename, "w", stdout );

		if ( prev_stdout == NULL )
			lerrsf( _( "could not create %s" ), outfilename );

		outfile_created = 1;
		}

	if ( skelname && (skelfile = fopen( skelname, "r" )) == NULL )
		lerrsf( _( "can't open skeleton file %s" ), skelname );

	if ( strcmp( prefix, "yy" ) )
		{
#define GEN_PREFIX(name) out_str3( "#define yy%s %s%s\n", name, prefix, name )
		if ( C_plus_plus )
			GEN_PREFIX( "FlexLexer" );
		else
			{
			GEN_PREFIX( "_create_buffer" );
			GEN_PREFIX( "_delete_buffer" );
			GEN_PREFIX( "_scan_buffer" );
			GEN_PREFIX( "_scan_string" );
			GEN_PREFIX( "_scan_bytes" );
			GEN_PREFIX( "_flex_debug" );
			GEN_PREFIX( "_init_buffer" );
			GEN_PREFIX( "_flush_buffer" );
			GEN_PREFIX( "_load_buffer_state" );
			GEN_PREFIX( "_switch_to_buffer" );
			GEN_PREFIX( "in" );
			GEN_PREFIX( "leng" );
			GEN_PREFIX( "lex" );
			GEN_PREFIX( "out" );
			GEN_PREFIX( "restart" );
			GEN_PREFIX( "text" );

			if ( do_yylineno )
				GEN_PREFIX( "lineno" );
			}

		if ( do_yywrap )
			GEN_PREFIX( "wrap" );

		outn( "" );
		}

	if ( did_outfilename )
		line_directive_out( stdout, 0 );

	skelout();
	}


/* flexend - terminate flex
 *
 * note
 *    This routine does not return.
 */

void flexend( exit_status )
int exit_status;

	{
	int tblsiz;
	int unlink();

	if ( skelfile != NULL )
		{
		if ( ferror( skelfile ) )
			lerrsf( _( "input error reading skeleton file %s" ),
				skelname );

		else if ( fclose( skelfile ) )
			lerrsf( _( "error closing skeleton file %s" ),
				skelname );
		}

	if ( exit_status != 0 && outfile_created )
		{
		if ( ferror( stdout ) )
			lerrsf( _( "error writing output file %s" ),
				outfilename );

		else if ( fclose( stdout ) )
			lerrsf( _( "error closing output file %s" ),
				outfilename );

		else if ( unlink( outfilename ) )
			lerrsf( _( "error deleting output file %s" ),
				outfilename );
		}

	if ( backing_up_report && backing_up_file )
		{
		if ( num_backing_up == 0 )
			fprintf( backing_up_file, _( "No backing up.\n" ) );
		else if ( fullspd || fulltbl )
			fprintf( backing_up_file,
				_( "%d backing up (non-accepting) states.\n" ),
				num_backing_up );
		else
			fprintf( backing_up_file,
				_( "Compressed tables always back up.\n" ) );

		if ( ferror( backing_up_file ) )
			lerrsf( _( "error writing backup file %s" ),
				backing_name );

		else if ( fclose( backing_up_file ) )
			lerrsf( _( "error closing backup file %s" ),
				backing_name );
		}

	if ( printstats )
		{
		fprintf( stderr, _( "%s version %s usage statistics:\n" ),
			program_name, flex_version );

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

		if ( C_plus_plus )
			putc( '+', stderr );
		if ( backing_up_report )
			putc( 'b', stderr );
		if ( ddebug )
			putc( 'd', stderr );
		if ( caseins )
			putc( 'i', stderr );
		if ( lex_compat )
			putc( 'l', stderr );
		if ( performance_report > 0 )
			putc( 'p', stderr );
		if ( performance_report > 1 )
			putc( 'p', stderr );
		if ( spprdflt )
			putc( 's', stderr );
		if ( use_stdout )
			putc( 't', stderr );
		if ( printstats )
			putc( 'v', stderr );	/* always true! */
		if ( nowarn )
			putc( 'w', stderr );
		if ( interactive == false )
			putc( 'B', stderr );
		if ( interactive == true )
			putc( 'I', stderr );
		if ( ! gen_line_dirs )
			putc( 'L', stderr );
		if ( trace )
			putc( 'T', stderr );

		if ( csize == unspecified )
			/* We encountered an error fairly early on, so csize
			 * never got specified.  Define it now, to prevent
			 * bogus table sizes being written out below.
			 */
			csize = 256;

		if ( csize == 128 )
			putc( '7', stderr );
		else
			putc( '8', stderr );

		fprintf( stderr, " -C" );

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

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

		if ( skelname )
			fprintf( stderr, " -S%s", skelname );

		if ( strcmp( prefix, "yy" ) )
			fprintf( stderr, " -P%s", prefix );

		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 + num_eof_rules - 1 /* - 1 for def. rule */ );

		if ( num_backing_up == 0 )
			fprintf( stderr, _( "  No backing up\n" ) );
		else if ( fullspd || fulltbl )
			fprintf( stderr,
			_( "  %d backing-up (non-accepting) states\n" ),
				num_backing_up );
		else
			fprintf( stderr,
				_( "  Compressed tables always back-up\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 );
		}

	exit( exit_status );
	}


/* flexinit - initialize flex */

void flexinit( argc, argv )
int argc;
char **argv;
	{
	int i, sawcmpflag;
	char *arg, *mktemp();