lex.yy.c

L属性定义的利用lex和yacc做的计算器。

#endif

/* end tables serialization structures and prototypes */

/* Default declaration of generated scanner - a define so the user can
 * easily add parameters.
 */
#ifndef YY_DECL
#define YY_DECL_IS_OURS 1

extern int yylex (void);

#define YY_DECL int yylex (void)
#endif /* !YY_DECL */

/* Code executed at the beginning of each rule, after yytext and yyleng
 * have been set up.
 */
#ifndef YY_USER_ACTION
#define YY_USER_ACTION
#endif

/* Code executed at the end of each rule. */
#ifndef YY_BREAK
#define YY_BREAK break;
#endif

#define YY_RULE_SETUP \
	YY_USER_ACTION

/** The main scanner function which does all the work.
 */
YY_DECL
{
	register yy_state_type yy_current_state;
	register char *yy_cp, *yy_bp;
	register int yy_act;
    
#line 5 "lexer.l"

#line 623 "lex.yy.c"

	if ( !(yy_init) )
		{
		(yy_init) = 1;

#ifdef YY_USER_INIT
		YY_USER_INIT;
#endif

		if ( ! (yy_start) )
			(yy_start) = 1;	/* first start state */

		if ( ! yyin )
			yyin = stdin;

		if ( ! yyout )
			yyout = stdout;

		if ( ! YY_CURRENT_BUFFER ) {
			yyensure_buffer_stack ();
			YY_CURRENT_BUFFER_LVALUE =
				yy_create_buffer(yyin,YY_BUF_SIZE );
		}

		yy_load_buffer_state( );
		}

	while ( 1 )		/* loops until end-of-file is reached */
		{
		yy_cp = (yy_c_buf_p);

		/* Support of yytext. */
		*yy_cp = (yy_hold_char);

		/* yy_bp points to the position in yy_ch_buf of the start of
		 * the current run.
		 */
		yy_bp = yy_cp;

		yy_current_state = (yy_start);
yy_match:
		do
			{
			register YY_CHAR yy_c = yy_ec[YY_SC_TO_UI(*yy_cp)];
			if ( yy_accept[yy_current_state] )
				{
				(yy_last_accepting_state) = yy_current_state;
				(yy_last_accepting_cpos) = yy_cp;
				}
			while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
				{
				yy_current_state = (int) yy_def[yy_current_state];
				if ( yy_current_state >= 18 )
					yy_c = yy_meta[(unsigned int) yy_c];
				}
			yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
			++yy_cp;
			}
		while ( yy_base[yy_current_state] != 20 );

yy_find_action:
		yy_act = yy_accept[yy_current_state];
		if ( yy_act == 0 )
			{ /* have to back up */
			yy_cp = (yy_last_accepting_cpos);
			yy_current_state = (yy_last_accepting_state);
			yy_act = yy_accept[yy_current_state];
			}

		YY_DO_BEFORE_ACTION;

do_action:	/* This label is used only to access EOF actions. */

		switch ( yy_act )
	{ /* beginning of action switch */
			case 0: /* must back up */
			/* undo the effects of YY_DO_BEFORE_ACTION */
			*yy_cp = (yy_hold_char);
			yy_cp = (yy_last_accepting_cpos);
			yy_current_state = (yy_last_accepting_state);
			goto yy_find_action;

case 1:
YY_RULE_SETUP
#line 6 "lexer.l"
{ yylval = 1; return INTEGER; }
	YY_BREAK
case 2:
YY_RULE_SETUP
#line 7 "lexer.l"
{ yylval = 0; return REAL; }
	YY_BREAK
case 3:
YY_RULE_SETUP
#line 8 "lexer.l"
{ return IDENTIFIER; }
	YY_BREAK
case 4:
YY_RULE_SETUP
#line 9 "lexer.l"
{ return yytext[0]; }
	YY_BREAK
case 5:
YY_RULE_SETUP
#line 10 "lexer.l"
{ return yytext[0]; }
	YY_BREAK
case 6:
YY_RULE_SETUP
#line 11 "lexer.l"

	YY_BREAK
case 7:
YY_RULE_SETUP
#line 12 "lexer.l"
ECHO;
	YY_BREAK
#line 741 "lex.yy.c"
case YY_STATE_EOF(INITIAL):
	yyterminate();

	case YY_END_OF_BUFFER:
		{
		/* Amount of text matched not including the EOB char. */
		int yy_amount_of_matched_text = (int) (yy_cp - (yytext_ptr)) - 1;

		/* Undo the effects of YY_DO_BEFORE_ACTION. */
		*yy_cp = (yy_hold_char);
		YY_RESTORE_YY_MORE_OFFSET

		if ( YY_CURRENT_BUFFER_LVALUE->yy_buffer_status == YY_BUFFER_NEW )
			{
			/* We're scanning a new file or input source.  It's
			 * possible that this happened because the user
			 * just pointed yyin at a new source and called
			 * yylex().  If so, then we have to assure
			 * consistency between YY_CURRENT_BUFFER and our
			 * globals.  Here is the right place to do so, because
			 * this is the first action (other than possibly a
			 * back-up) that will match for the new input source.
			 */
			(yy_n_chars) = YY_CURRENT_BUFFER_LVALUE->yy_n_chars;
			YY_CURRENT_BUFFER_LVALUE->yy_input_file = yyin;
			YY_CURRENT_BUFFER_LVALUE->yy_buffer_status = YY_BUFFER_NORMAL;
			}

		/* Note that here we test for yy_c_buf_p "<=" to the position
		 * of the first EOB in the buffer, since yy_c_buf_p will
		 * already have been incremented past the NUL character
		 * (since all states make transitions on EOB to the
		 * end-of-buffer state).  Contrast this with the test
		 * in input().
		 */
		if ( (yy_c_buf_p) <= &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)] )
			{ /* This was really a NUL. */
			yy_state_type yy_next_state;

			(yy_c_buf_p) = (yytext_ptr) + yy_amount_of_matched_text;

			yy_current_state = yy_get_previous_state(  );

			/* Okay, we're now positioned to make the NUL
			 * transition.  We couldn't have
			 * yy_get_previous_state() go ahead and do it
			 * for us because it doesn't know how to deal
			 * with the possibility of jamming (and we don't
			 * want to build jamming into it because then it
			 * will run more slowly).
			 */

			yy_next_state = yy_try_NUL_trans( yy_current_state );

			yy_bp = (yytext_ptr) + YY_MORE_ADJ;

			if ( yy_next_state )
				{
				/* Consume the NUL. */
				yy_cp = ++(yy_c_buf_p);
				yy_current_state = yy_next_state;
				goto yy_match;
				}

			else
				{
				yy_cp = (yy_c_buf_p);
				goto yy_find_action;
				}
			}

		else switch ( yy_get_next_buffer(  ) )
			{
			case EOB_ACT_END_OF_FILE:
				{
				(yy_did_buffer_switch_on_eof) = 0;

				if ( yywrap( ) )
					{
					/* Note: because we've taken care in
					 * yy_get_next_buffer() to have set up
					 * yytext, we can now set up
					 * yy_c_buf_p so that if some total
					 * hoser (like flex itself) wants to
					 * call the scanner after we return the
					 * YY_NULL, it'll still work - another
					 * YY_NULL will get returned.
					 */
					(yy_c_buf_p) = (yytext_ptr) + YY_MORE_ADJ;

					yy_act = YY_STATE_EOF(YY_START);
					goto do_action;
					}

				else
					{
					if ( ! (yy_did_buffer_switch_on_eof) )
						YY_NEW_FILE;
					}
				break;
				}

			case EOB_ACT_CONTINUE_SCAN:
				(yy_c_buf_p) =
					(yytext_ptr) + yy_amount_of_matched_text;

				yy_current_state = yy_get_previous_state(  );

				yy_cp = (yy_c_buf_p);
				yy_bp = (yytext_ptr) + YY_MORE_ADJ;
				goto yy_match;

			case EOB_ACT_LAST_MATCH:
				(yy_c_buf_p) =
				&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)];

				yy_current_state = yy_get_previous_state(  );

				yy_cp = (yy_c_buf_p);
				yy_bp = (yytext_ptr) + YY_MORE_ADJ;
				goto yy_find_action;
			}
		break;
		}

	default:
		YY_FATAL_ERROR(
			"fatal flex scanner internal error--no action found" );
	} /* end of action switch */
		} /* end of scanning one token */
} /* end of yylex */

/* yy_get_next_buffer - try to read in a new buffer
 *
 * Returns a code representing an action:
 *	EOB_ACT_LAST_MATCH -
 *	EOB_ACT_CONTINUE_SCAN - continue scanning from current position
 *	EOB_ACT_END_OF_FILE - end of file
 */
static int yy_get_next_buffer (void)
{
    	register char *dest = YY_CURRENT_BUFFER_LVALUE->yy_ch_buf;
	register char *source = (yytext_ptr);
	register int number_to_move, i;
	int ret_val;

	if ( (yy_c_buf_p) > &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars) + 1] )
		YY_FATAL_ERROR(
		"fatal flex scanner internal error--end of buffer missed" );

	if ( YY_CURRENT_BUFFER_LVALUE->yy_fill_buffer == 0 )
		{ /* Don't try to fill the buffer, so this is an EOF. */
		if ( (yy_c_buf_p) - (yytext_ptr) - YY_MORE_ADJ == 1 )
			{
			/* We matched a single character, the EOB, so
			 * treat this as a final EOF.
			 */
			return EOB_ACT_END_OF_FILE;
			}

		else
			{
			/* We matched some text prior to the EOB, first
			 * process it.
			 */
			return EOB_ACT_LAST_MATCH;
			}
		}

	/* Try to read more data. */

	/* First move last chars to start of buffer. */
	number_to_move = (int) ((yy_c_buf_p) - (yytext_ptr)) - 1;

	for ( i = 0; i < number_to_move; ++i )
		*(dest++) = *(source++);

	if ( YY_CURRENT_BUFFER_LVALUE->yy_buffer_status == YY_BUFFER_EOF_PENDING )
		/* don't do the read, it's not guaranteed to return an EOF,
		 * just force an EOF
		 */
		YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars) = 0;

	else
		{
			int num_to_read =
			YY_CURRENT_BUFFER_LVALUE->yy_buf_size - number_to_move - 1;

		while ( num_to_read <= 0 )
			{ /* Not enough room in the buffer - grow it. */

			/* just a shorter name for the current buffer */
			YY_BUFFER_STATE b = YY_CURRENT_BUFFER;

			int yy_c_buf_p_offset =
				(int) ((yy_c_buf_p) - b->yy_ch_buf);

			if ( b->yy_is_our_buffer )
				{
				int new_size = b->yy_buf_size * 2;

				if ( new_size <= 0 )
					b->yy_buf_size += b->yy_buf_size / 8;
				else
					b->yy_buf_size *= 2;

				b->yy_ch_buf = (char *)
					/* Include room in for 2 EOB chars. */
					yyrealloc((void *) b->yy_ch_buf,b->yy_buf_size + 2  );
				}
			else
				/* Can't grow it, we don't own it. */
				b->yy_ch_buf = 0;

			if ( ! b->yy_ch_buf )
				YY_FATAL_ERROR(
				"fatal error - scanner input buffer overflow" );

			(yy_c_buf_p) = &b->yy_ch_buf[yy_c_buf_p_offset];

			num_to_read = YY_CURRENT_BUFFER_LVALUE->yy_buf_size -
						number_to_move - 1;

			}

		if ( num_to_read > YY_READ_BUF_SIZE )
			num_to_read = YY_READ_BUF_SIZE;

		/* Read in more data. */
		YY_INPUT( (&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move]),
			(yy_n_chars), (size_t) num_to_read );

		YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars);
		}

	if ( (yy_n_chars) == 0 )
		{
		if ( number_to_move == YY_MORE_ADJ )
			{
			ret_val = EOB_ACT_END_OF_FILE;
			yyrestart(yyin  );
			}

		else
			{
			ret_val = EOB_ACT_LAST_MATCH;
			YY_CURRENT_BUFFER_LVALUE->yy_buffer_status =
				YY_BUFFER_EOF_PENDING;
			}
		}

	else
		ret_val = EOB_ACT_CONTINUE_SCAN;

	if ((yy_size_t) ((yy_n_chars) + number_to_move) > YY_CURRENT_BUFFER_LVALUE->yy_buf_size) {
		/* Extend the array by 50%, plus the number we really need. */
		yy_size_t new_size = (yy_n_chars) + number_to_move + ((yy_n_chars) >> 1);
		YY_CURRENT_BUFFER_LVALUE->yy_ch_buf = (char *) yyrealloc((void *) YY_CURRENT_BUFFER_LVALUE->yy_ch_buf,new_size  );
		if ( ! YY_CURRENT_BUFFER_LVALUE->yy_ch_buf )
			YY_FATAL_ERROR( "out of dynamic memory in yy_get_next_buffer()" );
	}

	(yy_n_chars) += number_to_move;
	YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)] = YY_END_OF_BUFFER_CHAR;
	YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars) + 1] = YY_END_OF_BUFFER_CHAR;

	(yytext_ptr) = &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[0];

	return ret_val;
}

/* yy_get_previous_state - get the state just before the EOB char was reached */

    static yy_state_type yy_get_previous_state (void)
{
	register yy_state_type yy_current_state;
	register char *yy_cp;
    
	yy_current_state = (yy_start);

	for ( yy_cp = (yytext_ptr) + YY_MORE_ADJ; yy_cp < (yy_c_buf_p); ++yy_cp )
		{
		register YY_CHAR yy_c = (*yy_cp ? yy_ec[YY_SC_TO_UI(*yy_cp)] : 1);
		if ( yy_accept[yy_current_state] )
			{
			(yy_last_accepting_state) = yy_current_state;
			(yy_last_accepting_cpos) = yy_cp;
			}
		while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
			{
			yy_current_state = (int) yy_def[yy_current_state];
			if ( yy_current_state >= 18 )
				yy_c = yy_meta[(unsigned int) yy_c];
			}
		yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
		}

	return yy_current_state;
}

/* yy_try_NUL_trans - try to make a transition on the NUL character
 *
 * synopsis
 *	next_state = yy_try_NUL_trans( current_state );
 */
    static yy_state_type yy_try_NUL_trans  (yy_state_type yy_current_state )
{
	register int yy_is_jam;
    	register char *yy_cp = (yy_c_buf_p);

	register YY_CHAR yy_c = 1;
	if ( yy_accept[yy_current_state] )
		{
		(yy_last_accepting_state) = yy_current_state;
		(yy_last_accepting_cpos) = yy_cp;
		}
	while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
		{
		yy_current_state = (int) yy_def[yy_current_state];
		if ( yy_current_state >= 18 )
			yy_c = yy_meta[(unsigned int) yy_c];
		}
	yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
	yy_is_jam = (yy_current_state == 17);

	return yy_is_jam ? 0 : yy_current_state;
}

    static void yyunput (int c, register char * yy_bp )
{
	register char *yy_cp;
    
    yy_cp = (yy_c_buf_p);

	/* undo effects of setting up yytext */
	*yy_cp = (yy_hold_char);

	if ( yy_cp < YY_CURRENT_BUFFER_LVALUE->yy_ch_buf + 2 )
		{ /* need to shift things up to make room */
		/* +2 for EOB chars. */
		register int number_to_move = (yy_n_chars) + 2;
		register char *dest = &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[
					YY_CURRENT_BUFFER_LVALUE->yy_buf_size + 2];
		register char *source =
				&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move];

		while ( source > YY_CURRENT_BUFFER_LVALUE->yy_ch_buf )
			*--dest = *--source;

		yy_cp += (int) (dest - source);
		yy_bp += (int) (dest - source);
		YY_CURRENT_BUFFER_LVALUE->yy_n_chars =
			(yy_n_chars) = YY_CURRENT_BUFFER_LVALUE->yy_buf_size;

		if ( yy_cp < YY_CURRENT_BUFFER_LVALUE->yy_ch_buf + 2 )
			YY_FATAL_ERROR( "flex scanner push-back overflow" );
		}

	*--yy_cp = (char) c;

	(yytext_ptr) = yy_bp;
	(yy_hold_char) = *yy_cp;
	(yy_c_buf_p) = yy_cp;
}

#ifndef YY_NO_INPUT
#ifdef __cplusplus
    static int yyinput (void)
#else
    static int input  (void)
#endif

{
	int c;
    
	*(yy_c_buf_p) = (yy_hold_char);

	if ( *(yy_c_buf_p) == YY_END_OF_BUFFER_CHAR )
		{
		/* yy_c_buf_p now points to the character we want to return.
		 * If this occurs *before* the EOB characters, then it's a
		 * valid NUL; if not, then we've hit the end of the buffer.
		 */
		if ( (yy_c_buf_p) < &YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[(yy_n_chars)] )
			/* This was really a NUL. */
			*(yy_c_buf_p) = '\0';

		else
			{ /* need more input */
			int offset = (yy_c_buf_p) - (yytext_ptr);
			++(yy_c_buf_p);

			switch ( yy_get_next_buffer(  ) )
				{
				case EOB_ACT_LAST_MATCH:
					/* This happens because yy_g_n_b()
					 * sees that we've accumulated a
					 * token and flags that we need to
					 * try matching the token before
					 * proceeding.  But for input(),
					 * there's no matching to consider.
					 * So convert the EOB_ACT_LAST_MATCH
					 * to EOB_ACT_END_OF_FILE.
					 */

					/* Reset buffer status. */
					yyrestart(yyin );

					/*FALLTHROUGH*/

				case EOB_ACT_END_OF_FILE:
					{
					if ( yywrap( ) )
						return EOF;

					if ( ! (yy_did_buffer_switch_on_eof) )
						YY_NEW_FILE;
#ifdef __cplusplus
					return yyinput();
#else
					return input();
#endif