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📄 flex.skel.old

📁 C++版 词法分析、语法分析器
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/* A lexical scanner generated by flex */

/* scanner skeleton version:
 * $Header: c:\\program\040files\\development\\cvs\040repository/flex++/MISC/flex.skel.old,v 1.1.1.1 2002/04/13 06:01:33 Bear Exp $
 */

#define FLEX_SCANNER

#include <stdio.h>


/* cfront 1.2 defines "c_plusplus" instead of "__cplusplus" */
#ifdef c_plusplus
#ifndef __cplusplus
#define __cplusplus
#endif
#endif


#ifdef __cplusplus

#include <stdlib.h>
#include <osfcn.h>

/* use prototypes in function declarations */
#define YY_USE_PROTOS

/* the "const" storage-class-modifier is valid */
#define YY_USE_CONST

#else	/* ! __cplusplus */

#ifdef __STDC__

#ifdef __GNUC__
#include <stddef.h>
void *malloc( size_t );
void free( void* );
#else
#include <stdlib.h>
#endif	/* __GNUC__ */

#define YY_USE_PROTOS
#define YY_USE_CONST

#endif	/* __STDC__ */
#endif	/* ! __cplusplus */


#ifdef __TURBOC__
#define YY_USE_CONST
#endif


#ifndef YY_USE_CONST
#define const
#endif


#ifdef YY_USE_PROTOS
#define YY_PROTO(proto) proto
#else
#define YY_PROTO(proto) ()
/* we can't get here if it's an ANSI C compiler, or a C++ compiler,
 * so it's got to be a K&R compiler, and therefore there's no standard
 * place from which to include these definitions
 */
char *malloc();
int free();
int read();
#endif


/* amount of stuff to slurp up with each read */
#ifndef YY_READ_BUF_SIZE
#define YY_READ_BUF_SIZE 8192
#endif

/* returned upon end-of-file */
#define YY_END_TOK 0

/* copy whatever the last rule matched to the standard output */

/* cast to (char *) is because for 8-bit chars, yytext is (unsigned char *) */
/* this used to be an fputs(), but since the string might contain NUL's,
 * we now use fwrite()
 */
#define ECHO (void) fwrite( (char *) yytext, yyleng, 1, yyout )

/* gets input and stuffs it into "buf".  number of characters read, or YY_NULL,
 * is returned in "result".
 */
#define YY_INPUT(buf,result,max_size) \
	if ( (result = read( fileno(yyin), (char *) buf, max_size )) < 0 ) \
	    YY_FATAL_ERROR( "read() in flex scanner failed" );
#define YY_NULL 0

/* no semi-colon after return; correct usage is to write "yyterminate();" -
 * we don't want an extra ';' after the "return" because that will cause
 * some compilers to complain about unreachable statements.
 */
#define yyterminate() return ( YY_NULL )

/* report a fatal error */

/* The funky do-while is used to turn this macro definition into
 * a single C statement (which needs a semi-colon terminator).
 * This avoids problems with code like:
 *
 * 	if ( something_happens )
 *		YY_FATAL_ERROR( "oops, the something happened" );
 *	else
 *		everything_okay();
 *
 * Prior to using the do-while the compiler would get upset at the
 * "else" because it interpreted the "if" statement as being all
 * done when it reached the ';' after the YY_FATAL_ERROR() call.
 */

#define YY_FATAL_ERROR(msg) \
	do \
		{ \
		(void) fputs( msg, stderr ); \
		(void) putc( '\n', stderr ); \
		exit( 1 ); \
		} \
	while ( 0 )

/* default yywrap function - always treat EOF as an EOF */
#define yywrap() 1

/* enter a start condition.  This macro really ought to take a parameter,
 * but we do it the disgusting crufty way forced on us by the ()-less
 * definition of BEGIN
 */
#define BEGIN yy_start = 1 + 2 *

/* action number for EOF rule of a given start state */
#define YY_STATE_EOF(state) (YY_END_OF_BUFFER + state + 1)

/* special action meaning "start processing a new file" */
#define YY_NEW_FILE \
	do \
		{ \
		yy_init_buffer( yy_current_buffer, yyin ); \
		yy_load_buffer_state(); \
		} \
	while ( 0 )

/* default declaration of generated scanner - a define so the user can
 * easily add parameters
 */
#define YY_DECL int yylex YY_PROTO(( void )) 

/* code executed at the end of each rule */
#define YY_BREAK break;

#define YY_END_OF_BUFFER_CHAR 0

#ifndef YY_BUF_SIZE
#define YY_BUF_SIZE (YY_READ_BUF_SIZE * 2) /* size of default input buffer */
#endif

typedef struct yy_buffer_state *YY_BUFFER_STATE;

%% section 1 definitions go here

/* done after the current pattern has been matched and before the
 * corresponding action - sets up yytext
 */
#define YY_DO_BEFORE_ACTION \
	yytext = yy_bp; \
%% code to fiddle yytext and yyleng for yymore() goes here
	yy_hold_char = *yy_cp; \
	*yy_cp = '\0'; \
	yy_c_buf_p = yy_cp;

#define EOB_ACT_CONTINUE_SCAN 0
#define EOB_ACT_END_OF_FILE 1
#define EOB_ACT_LAST_MATCH 2

/* return all but the first 'n' matched characters back to the input stream */
#define yyless(n) \
	do \
		{ \
		/* undo effects of setting up yytext */ \
		*yy_cp = yy_hold_char; \
		yy_c_buf_p = yy_cp = yy_bp + n; \
		YY_DO_BEFORE_ACTION; /* set up yytext again */ \
		} \
	while ( 0 )

#define unput(c) yyunput( c, yytext )


struct yy_buffer_state
    {
    FILE *yy_input_file;

    YY_CHAR *yy_ch_buf;		/* input buffer */
    YY_CHAR *yy_buf_pos;	/* current position in input buffer */

    /* size of input buffer in bytes, not including room for EOB characters*/
    int yy_buf_size;	

    /* number of characters read into yy_ch_buf, not including EOB characters */
    int yy_n_chars;

    int yy_eof_status;		/* whether we've seen an EOF on this buffer */
#define EOF_NOT_SEEN 0
    /* "pending" happens when the EOF has been seen but there's still
     * some text process
     */
#define EOF_PENDING 1
#define EOF_DONE 2
    };

static YY_BUFFER_STATE yy_current_buffer;

/* we provide macros for accessing buffer states in case in the
 * future we want to put the buffer states in a more general
 * "scanner state"
 */
#define YY_CURRENT_BUFFER yy_current_buffer


/* yy_hold_char holds the character lost when yytext is formed */
static YY_CHAR yy_hold_char;

static int yy_n_chars;		/* number of characters read into yy_ch_buf */



#ifndef YY_USER_ACTION
#define YY_USER_ACTION
#endif

#ifndef YY_USER_INIT
#define YY_USER_INIT
#endif

extern YY_CHAR *yytext;
extern int yyleng;
extern FILE *yyin, *yyout;

YY_CHAR *yytext;
int yyleng;

FILE *yyin = (FILE *) 0, *yyout = (FILE *) 0;

%% data tables for the DFA go here

/* these variables are all declared out here so that section 3 code can
 * manipulate them
 */
/* points to current character in buffer */
static YY_CHAR *yy_c_buf_p = (YY_CHAR *) 0;
static int yy_init = 1;		/* whether we need to initialize */
static int yy_start = 0;	/* start state number */

/* flag which is used to allow yywrap()'s to do buffer switches
 * instead of setting up a fresh yyin.  A bit of a hack ...
 */
static int yy_did_buffer_switch_on_eof;

static yy_state_type yy_get_previous_state YY_PROTO(( void ));
static yy_state_type yy_try_NUL_trans YY_PROTO(( yy_state_type current_state ));
static int yy_get_next_buffer YY_PROTO(( void ));
static void yyunput YY_PROTO(( YY_CHAR c, YY_CHAR *buf_ptr ));
void yyrestart YY_PROTO(( FILE *input_file ));
void yy_switch_to_buffer YY_PROTO(( YY_BUFFER_STATE new_buffer ));
void yy_load_buffer_state YY_PROTO(( void ));
YY_BUFFER_STATE yy_create_buffer YY_PROTO(( FILE *file, int size ));
void yy_delete_buffer YY_PROTO(( YY_BUFFER_STATE b ));
void yy_init_buffer YY_PROTO(( YY_BUFFER_STATE b, FILE *file ));

#define yy_new_buffer yy_create_buffer

#ifdef __cplusplus
static int yyinput YY_PROTO(( void ));
#else
static int input YY_PROTO(( void ));
#endif

YY_DECL
    {
    register yy_state_type yy_current_state;
    register YY_CHAR *yy_cp, *yy_bp;
    register int yy_act;

%% user's declarations go here

    if ( yy_init )
	{
	YY_USER_INIT;

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

	if ( ! yyin )
	    yyin = stdin;

	if ( ! yyout )
	    yyout = stdout;

	if ( yy_current_buffer )
	    yy_init_buffer( yy_current_buffer, yyin );
	else
	    yy_current_buffer = yy_create_buffer( yyin, YY_BUF_SIZE );

	yy_load_buffer_state();

	yy_init = 0;
	}

    while ( 1 )		/* loops until end-of-file is reached */
	{
%% yymore()-related code goes here
	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;

%% code to set up and find next match goes here

yy_find_action:
%% code to find the action number goes here

	YY_DO_BEFORE_ACTION;
	YY_USER_ACTION;

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

%% debug code goes here

	switch ( yy_act )
	    {
%% actions go here

	    case YY_END_OF_BUFFER:
		{
		/* amount of text matched not including the EOB char */
		int yy_amount_of_matched_text = yy_cp - yytext - 1;

		/* undo the effects of YY_DO_BEFORE_ACTION */
		*yy_cp = yy_hold_char;

		/* 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 yyinput().
		 */
		if ( yy_c_buf_p <= &yy_current_buffer->yy_ch_buf[yy_n_chars] )
		    /* this was really a NUL */
		    {
		    yy_state_type yy_next_state;

		    yy_c_buf_p = yytext + 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 + 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
			{
%% code to do backtracking for compressed tables and set up yy_cp goes here
			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 + YY_MORE_ADJ;

			    yy_act = YY_STATE_EOF((yy_start - 1) / 2);
			    goto do_action;
			    }

			else
			    {

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