yydebug.c

一个c语言写做的编译器的源码

    wprintw  (Stack_window, "a  (a)bort parse by reading EOI    \n");
    wprintw  (Stack_window, "b  modify or examine (b)reakpoint  \n");
    wprintw  (Stack_window, "d  set (d)elay time for go mode    \n");
    wprintw  (Stack_window, "f  read (f)ile                     \n");
    wprintw  (Stack_window, "g  (g)o (any key stops parse)      \n");
    wprintw  (Stack_window, "i  change (i)nput file             \n");
    wmove    (Stack_window, 0, 39 );
    wprintw  (Stack_window, "l  (l)og output to file");
    wmove    (Stack_window, 1, 39 );
    wprintw  (Stack_window, "n  (n)oninteractive mode");
    wmove    (Stack_window, 2, 39 );
    wprintw  (Stack_window, "q  (q)uit (exit to dos)");
    wmove    (Stack_window, 3, 39 );
    wprintw  (Stack_window, "r  (r)efresh stack window");
    wmove    (Stack_window, 4, 39 );
    wprintw  (Stack_window, "w  (w)rite screen to file or device\n");
    wmove    (Stack_window, 5, 39 );
    wprintw  (Stack_window, "x  Show current and prev. le(X)eme\n");
    wmove    (Stack_window, 7, (78-29)/2 );
    wprintw  (Stack_window, "Space or Enter to single step" );
    wrefresh (Stack_window );
}
PUBLIC	int yy_nextoken()
{
    /* Input a token from yylex() and echo to both the token and comment
     * windows. Yy_comment() writes to the log file too. Break if the input
     * breakpoint is set and the required token has just been read. The token
     * name is centered in the token window if it's short enough. It's
     * truncated at TOKEN_WIDTH characters otherwise.
     */

    static int 	tok = -1;		/* current token */
    char	*str;
    char	*lexeme;
    char	buf[ TOKEN_WIDTH ];
    extern char *Yy_stok[]; 		/* Generated by occs and llama */
    extern int  yylex P(( void ));

    if( tok >= 0 && (Interactive || Log) )
	yycomment( "Advance past %s\n", Yy_stok[tok] );

    lexeme = ((tok = Abort ? 0 : yylex()) == 0) ? "" : yytext;

    if( Interactive || Log )
	yycomment( "Read %s <%s>\n", str = Yy_stok[tok], lexeme );

    if( Interactive )
    {
			/* clear, then update, the token window */

	concat( TOKEN_WIDTH, buf, str, " ", lexeme, NULL );
        scrollok( Token_window,   TRUE  );
	NEWLINE ( Token_window 		);
        scrollok( Token_window,   FALSE );
	wprintw ( Token_window, "%0.*s", TOKEN_WIDTH - 2, buf );
	wrefresh( Token_window );

	if( L_breakpoint != -1  &&  L_breakpoint <= yylineno )
	{
	    L_breakpoint = -1;
	    Singlestep   =  1;
	    yy_pstack( 0, 1 );
	}
	else if( ( *I_breakpoint &&
	           (    ( isdigit(*I_breakpoint) && tok == atoi(I_breakpoint) )
		     || !strcmp( lexeme,	I_breakpoint)
	 	     || !strcmp( Yy_stok[tok],	I_breakpoint)
	           )
	         )
	       )
	{
	    Singlestep = 1;
	    yy_pstack( 0, 1 );
	}
    }

    delay();
    return tok;
}

/*----------------------------------------------------------------------*/

PUBLIC	void yy_break( production_number )
int  production_number;
{
    /*  Handles production-number breakpoints. If a break is required, start
     *  single stepping and print the stack. Stack breakpoints are handled in
     *  yy_pstack and input breakpoints are done in yy_nextoken().
     *
     *  If production_number == -1, a break is forced regardless of the value
     *  of P_breakpoint;
     */

    if( production_number == P_breakpoint || production_number == -1 )
    {
	Singlestep = 1;
	yy_pstack( 0, 1 );
    }
}

/*----------------------------------------------------------------------*/

PRIVATE int breakpoint()
{
    /* Set up a breakpoint by prompting the user for any required information.
     * Return true if we have to redraw the stack window because a help screen
     * was printed there.
     */

    int	 	type;
    char 	**p;
    char	buf[80];
    int  	rval    = 0;
    static char	*text[] =
    {
	"Select a breakpoint type (i,l,p,or s) or command (c or l):",
	"Type: Description:           Enter breakpoint as follows:",
	" i    input.....................number for token value",
	"                             or string for lexeme or token name",
	" l    input line read...........line number",
	" p    reduce by production......number for production number",
	" s    top-of-stack symbol.......number for state-stack item",
	"                             or string for symbol-stack item",
	" c = clear all breakpoints",
	" d = display (list) all breakpoints",
	NULL
    };

    if( !yyprompt("Enter type or command, ? for help, ESC aborts: ", buf,0) )
	return 1;

    if( *buf == '?' )
    {
	rval = 1;
	werase   (Stack_window);
	wmove    (Stack_window, 0, 0);

	for( p = text; *p; p )
	    wprintw(Stack_window, "%s\n", *p++ );

	wrefresh (Stack_window);
	if( !yyprompt("Enter breakpoint type or command, ESC aborts: ", buf,0))
	    return rval;
    }

    if( (type = *buf)  == 'p' )
    {
	if( yyprompt("Production number or ESC to cancel: ", buf, 1 ))
	{
	    if( !isdigit( *buf ))
		yyprompt("Must be a number, press any key to continue.", buf,0);
	    else
		P_breakpoint = atoi( buf );
	}
    }
    else if( type == 'l' )
    {
	if( yyprompt("Input line number or ESC to cancel: ", buf, 1 ))
	    L_breakpoint = atoi( buf );
    }
    else if( type == 'i' || type == 's' )
    {
	if( yyprompt("Symbol value or ESC to cancel: ", buf, 1 ))
	    strncpy( type == 'i' ? I_breakpoint : S_breakpoint, buf, BRKLEN );
    }
    else
    {
	switch( type )
	{
	case 'c':
		P_breakpoint  = -1;
		L_breakpoint  = -1;
		*S_breakpoint = 0;
		*I_breakpoint = 0;
		break;

	case 'd':
		rval = 1;
		werase (Stack_window);
		wmove  (Stack_window, 0, 0);

		wprintw(Stack_window,
		     P_breakpoint == -1 ? "Production = none\n"
					: "Production = %d\n", P_breakpoint);

		wprintw(Stack_window, "Stack      = %s\n",
					*S_breakpoint ? S_breakpoint : "none" );

		wprintw(Stack_window, "Input      = %s\n",
					*I_breakpoint ? I_breakpoint : "none" );
		wprintw(Stack_window,
		     I_breakpoint == 0	? "Input line = none\n"
					: "Input line = %d\n", I_breakpoint);
		wrefresh(Stack_window);
		NEWLINE (Prompt_window);
		presskey();
		break;

	default:
		yyprompt("Illegal command or type, Press any key.", buf, 0);
		break;
        }
    }

    return rval;
}
PRIVATE	int	new_input_file( buf )
char	*buf;
{
    /* Open up a new input file. Input must come from a file because the
     * keyboard is used to get commands. In theory, you can use both standard
     * input and the keyboard (by opening the console as another stream), but I
     * had difficulties doing this in a portable way, and eventually gave up.
     * It's not that big a deal to require that test input be in a file.
     */

    NEWLINE(  Prompt_window );
    wrefresh( Prompt_window );

    if( ii_newfile( buf ) != -1 )
	Inp_fm_file = 1;
    else
    {
	wprintw(Prompt_window, "Can't open %s.", buf );
	presskey();
    }
    return Inp_fm_file;
}

/*----------------------------------------------------------------------*/

PRIVATE  FILE	*to_log( buf )
char	*buf;
{
    /* Set up everything to log output to a file (open the log file, etc.). */

    if( !yyprompt("Log-file name (CR for \"log\", ESC cancels): ", buf,1) )
	return NULL;

    if( !*buf )
	strcpy( buf, "log" );

    if( !(Log = fopen( buf, "w")) )
    {
        NEWLINE(Prompt_window );
	wprintw(Prompt_window, "Can't open %s", buf );
	presskey();
	return NULL;
    }

    if( !yyprompt("Log comment-window output? (y/n, CR=y): ", buf,0) )
	return NULL;
    else
	No_comment_pix = (*buf == 'n');

    if( !yyprompt( "Print stack pictures in log file? (y/n, CR=y): ",buf,0) )
	return NULL;

    if( !(No_stack_pix = (*buf == 'n')) )
    {
	if( !yyprompt( "Print stacks horizontally? (y/n, CR=y): ",buf,0) )
	    return NULL;

	if( Horiz_stack_pix = (*buf != 'n') )
	{
	    if( !yyprompt("Print SYMBOL stack (y/n, CR=y): ",buf,0) )
		return NULL;
	    Sym_pix = (*buf != 'n');

	    if( !yyprompt("Print PARSE  stack (y/n, CR=y): ",buf,0) )
		return NULL;
	    Parse_pix = (*buf != 'n');

	    if( !yyprompt("Print VALUE  stack (y/n, CR=y): ",buf,0) )
		return NULL;
	    Attr_pix = (*buf != 'n');
	}
    }
    return Log;
}

/*----------------------------------------------------------------------*/

PRIVATE	int  input_char( ANSI(void) )	  /* void argument illegal under UNIX */
{
    /* Get a character from the input window and echo it explicitly. If we've
     * compiled under Unix, reset the character-available flag.
     */

    int c;

    if( (c = wgetch(Prompt_window) & 0x7f) != ESC )
	waddch( Prompt_window, c );

    UNIX( Char_avail = 0; )
    return c;
}

/*----------------------------------------------------------------------*/

PUBLIC int yyprompt( prompt, buf, getstring )
char *prompt, *buf;
int  getstring;	   /* get entire string (as compared to a single character */
{
    /* Print a prompt and then wait for a reply, load the typed characters into
     * buf. ^H (destructive backspace) is supported. An ESC causes yyprompt()
     * to return 0 immediately, otherwise 1 is returned. The ESC is not put
     * into the buffer. If "getstring" is true, an entire string is fetched and
     * prompt returns when the newline is typed. If "getstring" is false, then
     * one character is fetched and yyprompt() returns immediately after getting
     * that character. Leading and trailing white space is stripped from the
     * line if getstring is true. (You can get a single space character if it's
     * false, however.)
     */

    register int  c;
    int		  y, x;
    char	  *startbuf = buf;

    NEWLINE ( Prompt_window		  );
    wprintw ( Prompt_window, "%s", prompt );
    wrefresh( Prompt_window		  );

    if( !getstring )
	c = *buf++ = input_char();
    else
    {
	while( (c = input_char()) != '\n'  &&  c != ESC )
	{
	    if( isspace(c) && buf==startbuf )
		continue;			/* skip leading white space */

	    if( c != '\b' )
	    	*buf++ = c;
	    else			   /* handle destructive backspace */
	    {
		getyx( Prompt_window, y, x );

		if( buf <= startbuf )
		    wmove ( Prompt_window, y, x+1 );
		else
		{
		    waddch( Prompt_window, ' '  );
		    wmove ( Prompt_window, y, x );
		    --buf;
		}
	    }
	    wrefresh( Prompt_window );
	}

	while( isspace( buf[-1] )  &&  buf > startbuf )
	    --buf;		/* Strip trailing white space */
    }
    *buf = 0;
    return (c != ESC);
}

/*----------------------------------------------------------------------*/

PRIVATE	void presskey()
{
    /* Ask for a key to be pressed and wait for it.  Note that this command
     * does a refresh, but it intentionally does not clear the window before
     * printing the prompt.
     */

    wprintw ( Prompt_window, " Press any key: " );
    wrefresh( Prompt_window );
    input_char();
}