scan-skel.c

GNU的词法/语法分析器bison源码

	if ( ! b )
		return;

	if ( b == YY_CURRENT_BUFFER ) /* Not sure if we should pop here. */
		YY_CURRENT_BUFFER_LVALUE = (YY_BUFFER_STATE) 0;

	if ( b->yy_is_our_buffer )
		skel_free((void *) b->yy_ch_buf  );

	skel_free((void *) b  );
}

/* %if-c-only */

/* %endif */

/* %if-c++-only */
/* %endif */

/* Initializes or reinitializes a buffer.
 * This function is sometimes called more than once on the same buffer,
 * such as during a skel_restart() or at EOF.
 */
/* %if-c-only */
    static void skel__init_buffer  (YY_BUFFER_STATE  b, FILE * file )
/* %endif */
/* %if-c++-only */
/* %endif */

{
	int oerrno = errno;
    
	skel__flush_buffer(b );

	b->yy_input_file = file;
	b->yy_fill_buffer = 1;

    /* If b is the current buffer, then skel__init_buffer was _probably_
     * called from skel_restart() or through yy_get_next_buffer.
     * In that case, we don't want to reset the lineno or column.
     */
    if (b != YY_CURRENT_BUFFER){
        b->yy_bs_lineno = 1;
        b->yy_bs_column = 0;
    }

/* %if-c-only */

        b->yy_is_interactive = 0;
    
/* %endif */
/* %if-c++-only */
/* %endif */
	errno = oerrno;
}

/** Discard all buffered characters. On the next scan, YY_INPUT will be called.
 * @param b the buffer state to be flushed, usually @c YY_CURRENT_BUFFER.
 * 
 */
/* %if-c-only */
    void skel__flush_buffer (YY_BUFFER_STATE  b )
/* %endif */
/* %if-c++-only */
/* %endif */
{
    	if ( ! b )
		return;

	b->yy_n_chars = 0;

	/* We always need two end-of-buffer characters.  The first causes
	 * a transition to the end-of-buffer state.  The second causes
	 * a jam in that state.
	 */
	b->yy_ch_buf[0] = YY_END_OF_BUFFER_CHAR;
	b->yy_ch_buf[1] = YY_END_OF_BUFFER_CHAR;

	b->yy_buf_pos = &b->yy_ch_buf[0];

	b->yy_at_bol = 1;
	b->yy_buffer_status = YY_BUFFER_NEW;

	if ( b == YY_CURRENT_BUFFER )
		skel__load_buffer_state( );
}

/* %if-c-or-c++ */
/** Pushes the new state onto the stack. The new state becomes
 *  the current state. This function will allocate the stack
 *  if necessary.
 *  @param new_buffer The new state.
 *  
 */
/* %if-c-only */
void skel_push_buffer_state (YY_BUFFER_STATE new_buffer )
/* %endif */
/* %if-c++-only */
/* %endif */
{
    	if (new_buffer == NULL)
		return;

	skel_ensure_buffer_stack();

	/* This block is copied from skel__switch_to_buffer. */
	if ( YY_CURRENT_BUFFER )
		{
		/* Flush out information for old buffer. */
		*(yy_c_buf_p) = (yy_hold_char);
		YY_CURRENT_BUFFER_LVALUE->yy_buf_pos = (yy_c_buf_p);
		YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars);
		}

	/* Only push if top exists. Otherwise, replace top. */
	if (YY_CURRENT_BUFFER)
		(yy_buffer_stack_top)++;
	YY_CURRENT_BUFFER_LVALUE = new_buffer;

	/* copied from skel__switch_to_buffer. */
	skel__load_buffer_state( );
	(yy_did_buffer_switch_on_eof) = 1;
}
/* %endif */

/* %if-c-or-c++ */
/** Removes and deletes the top of the stack, if present.
 *  The next element becomes the new top.
 *  
 */
/* %if-c-only */
void skel_pop_buffer_state (void)
/* %endif */
/* %if-c++-only */
/* %endif */
{
    	if (!YY_CURRENT_BUFFER)
		return;

	skel__delete_buffer(YY_CURRENT_BUFFER );
	YY_CURRENT_BUFFER_LVALUE = NULL;
	if ((yy_buffer_stack_top) > 0)
		--(yy_buffer_stack_top);

	if (YY_CURRENT_BUFFER) {
		skel__load_buffer_state( );
		(yy_did_buffer_switch_on_eof) = 1;
	}
}
/* %endif */

/* %if-c-or-c++ */
/* Allocates the stack if it does not exist.
 *  Guarantees space for at least one push.
 */
/* %if-c-only */
static void skel_ensure_buffer_stack (void)
/* %endif */
/* %if-c++-only */
/* %endif */
{
	int num_to_alloc;
    
	if (!(yy_buffer_stack)) {

		/* First allocation is just for 2 elements, since we don't know if this
		 * scanner will even need a stack. We use 2 instead of 1 to avoid an
		 * immediate realloc on the next call.
         */
		num_to_alloc = 1;
		(yy_buffer_stack) = (struct yy_buffer_state**)skel_alloc
								(num_to_alloc * sizeof(struct yy_buffer_state*)
								);
		
		memset((yy_buffer_stack), 0, num_to_alloc * sizeof(struct yy_buffer_state*));
				
		(yy_buffer_stack_max) = num_to_alloc;
		(yy_buffer_stack_top) = 0;
		return;
	}

	if ((yy_buffer_stack_top) >= ((yy_buffer_stack_max)) - 1){

		/* Increase the buffer to prepare for a possible push. */
		int grow_size = 8 /* arbitrary grow size */;

		num_to_alloc = (yy_buffer_stack_max) + grow_size;
		(yy_buffer_stack) = (struct yy_buffer_state**)skel_realloc
								((yy_buffer_stack),
								num_to_alloc * sizeof(struct yy_buffer_state*)
								);

		/* zero only the new slots.*/
		memset((yy_buffer_stack) + (yy_buffer_stack_max), 0, grow_size * sizeof(struct yy_buffer_state*));
		(yy_buffer_stack_max) = num_to_alloc;
	}
}
/* %endif */

/* %if-c-only */
/** Setup the input buffer state to scan directly from a user-specified character buffer.
 * @param base the character buffer
 * @param size the size in bytes of the character buffer
 * 
 * @return the newly allocated buffer state object. 
 */
YY_BUFFER_STATE skel__scan_buffer  (char * base, yy_size_t  size )
{
	YY_BUFFER_STATE b;
    
	if ( size < 2 ||
	     base[size-2] != YY_END_OF_BUFFER_CHAR ||
	     base[size-1] != YY_END_OF_BUFFER_CHAR )
		/* They forgot to leave room for the EOB's. */
		return 0;

	b = (YY_BUFFER_STATE) skel_alloc(sizeof( struct yy_buffer_state )  );
	if ( ! b )
		YY_FATAL_ERROR( "out of dynamic memory in skel__scan_buffer()" );

	b->yy_buf_size = size - 2;	/* "- 2" to take care of EOB's */
	b->yy_buf_pos = b->yy_ch_buf = base;
	b->yy_is_our_buffer = 0;
	b->yy_input_file = 0;
	b->yy_n_chars = b->yy_buf_size;
	b->yy_is_interactive = 0;
	b->yy_at_bol = 1;
	b->yy_fill_buffer = 0;
	b->yy_buffer_status = YY_BUFFER_NEW;

	skel__switch_to_buffer(b  );

	return b;
}
/* %endif */

/* %if-c-only */
/** Setup the input buffer state to scan a string. The next call to skel_lex() will
 * scan from a @e copy of @a str.
 * @param str a NUL-terminated string to scan
 * 
 * @return the newly allocated buffer state object.
 * @note If you want to scan bytes that may contain NUL values, then use
 *       skel__scan_bytes() instead.
 */
YY_BUFFER_STATE skel__scan_string (yyconst char * yy_str )
{
    
	return skel__scan_bytes(yy_str,strlen(yy_str) );
}
/* %endif */

/* %if-c-only */
/** Setup the input buffer state to scan the given bytes. The next call to skel_lex() will
 * scan from a @e copy of @a bytes.
 * @param bytes the byte buffer to scan
 * @param len the number of bytes in the buffer pointed to by @a bytes.
 * 
 * @return the newly allocated buffer state object.
 */
YY_BUFFER_STATE skel__scan_bytes  (yyconst char * bytes, int  len )
{
	YY_BUFFER_STATE b;
	char *buf;
	yy_size_t n;
	int i;
    
	/* Get memory for full buffer, including space for trailing EOB's. */
	n = len + 2;
	buf = (char *) skel_alloc(n  );
	if ( ! buf )
		YY_FATAL_ERROR( "out of dynamic memory in skel__scan_bytes()" );

	for ( i = 0; i < len; ++i )
		buf[i] = bytes[i];

	buf[len] = buf[len+1] = YY_END_OF_BUFFER_CHAR;

	b = skel__scan_buffer(buf,n );
	if ( ! b )
		YY_FATAL_ERROR( "bad buffer in skel__scan_bytes()" );

	/* It's okay to grow etc. this buffer, and we should throw it
	 * away when we're done.
	 */
	b->yy_is_our_buffer = 1;

	return b;
}
/* %endif */

#ifndef YY_EXIT_FAILURE
#define YY_EXIT_FAILURE 2
#endif

/* %if-c-only */
static void yy_fatal_error (yyconst char* msg )
{
    	(void) fprintf( stderr, "%s\n", msg );
	exit( YY_EXIT_FAILURE );
}
/* %endif */
/* %if-c++-only */
/* %endif */

/* Redefine yyless() so it works in section 3 code. */

#undef yyless
#define yyless(n) \
	do \
		{ \
		/* Undo effects of setting up skel_text. */ \
        int yyless_macro_arg = (n); \
        YY_LESS_LINENO(yyless_macro_arg);\
		skel_text[skel_leng] = (yy_hold_char); \
		(yy_c_buf_p) = skel_text + yyless_macro_arg; \
		(yy_hold_char) = *(yy_c_buf_p); \
		*(yy_c_buf_p) = '\0'; \
		skel_leng = yyless_macro_arg; \
		} \
	while ( 0 )

/* Accessor  methods (get/set functions) to struct members. */

/* %if-c-only */
/* %if-reentrant */
/* %endif */

/** Get the current line number.
 * 
 */
int skel_get_lineno  (void)
{
        
    return skel_lineno;
}

/** Get the input stream.
 * 
 */
FILE *skel_get_in  (void)
{
        return skel_in;
}

/** Get the output stream.
 * 
 */
FILE *skel_get_out  (void)
{
        return skel_out;
}

/** Get the length of the current token.
 * 
 */
int skel_get_leng  (void)
{
        return skel_leng;
}

/** Get the current token.
 * 
 */

char *skel_get_text  (void)
{
        return skel_text;
}

/* %if-reentrant */
/* %endif */

/** Set the current line number.
 * @param line_number
 * 
 */
void skel_set_lineno (int  line_number )
{
    
    skel_lineno = line_number;
}

/** Set the input stream. This does not discard the current
 * input buffer.
 * @param in_str A readable stream.
 * 
 * @see skel__switch_to_buffer
 */
void skel_set_in (FILE *  in_str )
{
        skel_in = in_str ;
}

void skel_set_out (FILE *  out_str )
{
        skel_out = out_str ;
}

int skel_get_debug  (void)
{
        return skel__flex_debug;
}

void skel_set_debug (int  bdebug )
{
        skel__flex_debug = bdebug ;
}

/* %endif */

/* %if-reentrant */
/* %if-bison-bridge */
/* %endif */
/* %endif */

/* %if-c-only SNIP! this currently causes conflicts with the c++ scanner */
/* skel_lex_destroy is for both reentrant and non-reentrant scanners. */
int skel_lex_destroy  (void)
{
    
    /* Pop the buffer stack, destroying each element. */
	while(YY_CURRENT_BUFFER){
		skel__delete_buffer(YY_CURRENT_BUFFER  );
		YY_CURRENT_BUFFER_LVALUE = NULL;
		skel_pop_buffer_state();
	}

	/* Destroy the stack itself. */
	skel_free((yy_buffer_stack) );
	(yy_buffer_stack) = NULL;

/* %if-reentrant */
/* %endif */
    return 0;
}
/* %endif */

/*
 * Internal utility routines.
 */

#ifndef yytext_ptr
static void yy_flex_strncpy (char* s1, yyconst char * s2, int n )
{
	register int i;
    	for ( i = 0; i < n; ++i )
		s1[i] = s2[i];
}
#endif

#ifdef YY_NEED_STRLEN
static int yy_flex_strlen (yyconst char * s )
{
	register int n;
    	for ( n = 0; s[n]; ++n )
		;

	return n;
}
#endif

void *skel_alloc (yy_size_t  size )
{
	return (void *) malloc( size );
}

void *skel_realloc  (void * ptr, yy_size_t  size )
{
	/* The cast to (char *) in the following accommodates both
	 * implementations that use char* generic pointers, and those
	 * that use void* generic pointers.  It works with the latter
	 * because both ANSI C and C++ allow castless assignment from
	 * any pointer type to void*, and deal with argument conversions
	 * as though doing an assignment.
	 */
	return (void *) realloc( (char *) ptr, size );
}

void skel_free (void * ptr )
{
	free( (char *) ptr );	/* see skel_realloc() for (char *) cast */
}

/* %if-tables-serialization definitions */
/* %define-yytables   The name for this specific scanner's tables. */
#define YYTABLES_NAME "yytables"
/* %endif */

/* %ok-for-header */

#undef YY_NEW_FILE
#undef YY_FLUSH_BUFFER
#undef yy_set_bol
#undef yy_new_buffer
#undef yy_set_interactive
#undef yytext_ptr
#undef YY_DO_BEFORE_ACTION

#ifdef YY_DECL_IS_OURS
#undef YY_DECL_IS_OURS
#undef YY_DECL
#endif
#line 93 "scan-skel.l"



/*------------------------.
| Scan a Bison skeleton.  |
`------------------------*/

void
scan_skel (FILE *in)
{
  skel_in = in;
  skel__flex_debug = trace_flag & trace_skeleton;
  skel_lex ();
  /* Reclaim Flex's buffers.  */
  skel__delete_buffer (YY_CURRENT_BUFFER);
}