comp_scan.c

ncurses-5.4

	switch (type) {
	case BOOLEAN:
	    _tracef("Token: Boolean; name='%s'",
		    _nc_curr_token.tk_name);
	    break;

	case NUMBER:
	    _tracef("Token: Number;  name='%s', value=%d",
		    _nc_curr_token.tk_name,
		    _nc_curr_token.tk_valnumber);
	    break;

	case STRING:
	    _tracef("Token: String;  name='%s', value=%s",
		    _nc_curr_token.tk_name,
		    _nc_visbuf(_nc_curr_token.tk_valstring));
	    break;

	case CANCEL:
	    _tracef("Token: Cancel; name='%s'",
		    _nc_curr_token.tk_name);
	    break;

	case NAMES:

	    _tracef("Token: Names; value='%s'",
		    _nc_curr_token.tk_name);
	    break;

	case EOF:
	    _tracef("Token: End of file");
	    break;

	default:
	    _nc_warning("Bad token type");
	}
    }
#endif

    if (dot_flag == TRUE)	/* if commented out, use the next one */
	type = _nc_get_token(silent);

    DEBUG(3, ("token: `%s', class %d",
	      _nc_curr_token.tk_name != 0 ? _nc_curr_token.tk_name :
	      "<null>",
	      type));

    return (type);
}

/*
 *	char
 *	trans_string(ptr)
 *
 *	Reads characters using next_char() until encountering a separator, nl,
 *	or end-of-file.  The returned value is the character which caused
 *	reading to stop.  The following translations are done on the input:
 *
 *		^X  goes to  ctrl-X (i.e. X & 037)
 *		{\E,\n,\r,\b,\t,\f}  go to
 *			{ESCAPE,newline,carriage-return,backspace,tab,formfeed}
 *		{\^,\\}  go to  {carat,backslash}
 *		\ddd (for ddd = up to three octal digits)  goes to the character ddd
 *
 *		\e == \E
 *		\0 == \200
 *
 */

NCURSES_EXPORT(char)
_nc_trans_string(char *ptr, char *last)
{
    int count = 0;
    int number = 0;
    int i, c;
    chtype ch, last_ch = '\0';
    bool ignored = FALSE;
    bool long_warning = FALSE;

    while ((ch = c = next_char()) != (chtype) separator && c != EOF) {
	if (ptr == (last - 1))
	    break;
	if ((_nc_syntax == SYN_TERMCAP) && c == '\n')
	    break;
	if (ch == '^' && last_ch != '%') {
	    ch = c = next_char();
	    if (c == EOF)
		_nc_err_abort(MSG_NO_INPUTS);

	    if (!(is7bits(ch) && isprint(ch))) {
		_nc_warning("Illegal ^ character - %s", unctrl(ch));
	    }
	    if (ch == '?') {
		*(ptr++) = '\177';
		if (_nc_tracing)
		    _nc_warning("Allow ^? as synonym for \\177");
	    } else {
		if ((ch &= 037) == 0)
		    ch = 128;
		*(ptr++) = (char) (ch);
	    }
	} else if (ch == '\\') {
	    ch = c = next_char();
	    if (c == EOF)
		_nc_err_abort(MSG_NO_INPUTS);

	    if (ch >= '0' && ch <= '7') {
		number = ch - '0';
		for (i = 0; i < 2; i++) {
		    ch = c = next_char();
		    if (c == EOF)
			_nc_err_abort(MSG_NO_INPUTS);

		    if (c < '0' || c > '7') {
			if (isdigit(c)) {
			    _nc_warning("Non-octal digit `%c' in \\ sequence", c);
			    /* allow the digit; it'll do less harm */
			} else {
			    push_back((char) c);
			    break;
			}
		    }

		    number = number * 8 + c - '0';
		}

		if (number == 0)
		    number = 0200;
		*(ptr++) = (char) number;
	    } else {
		switch (c) {
		case 'E':
		case 'e':
		    *(ptr++) = '\033';
		    break;

		case 'a':
		    *(ptr++) = '\007';
		    break;

		case 'l':
		case 'n':
		    *(ptr++) = '\n';
		    break;

		case 'r':
		    *(ptr++) = '\r';
		    break;

		case 'b':
		    *(ptr++) = '\010';
		    break;

		case 's':
		    *(ptr++) = ' ';
		    break;

		case 'f':
		    *(ptr++) = '\014';
		    break;

		case 't':
		    *(ptr++) = '\t';
		    break;

		case '\\':
		    *(ptr++) = '\\';
		    break;

		case '^':
		    *(ptr++) = '^';
		    break;

		case ',':
		    *(ptr++) = ',';
		    break;

		case ':':
		    *(ptr++) = ':';
		    break;

		case '\n':
		    continue;

		default:
		    _nc_warning("Illegal character %s in \\ sequence",
				unctrl(ch));
		    /* FALLTHRU */
		case '|':
		    *(ptr++) = (char) ch;
		}		/* endswitch (ch) */
	    }			/* endelse (ch < '0' ||  ch > '7') */
	}
	/* end else if (ch == '\\') */
	else if (ch == '\n' && (_nc_syntax == SYN_TERMINFO)) {
	    /* newlines embedded in a terminfo string are ignored */
	    ignored = TRUE;
	} else {
	    *(ptr++) = (char) ch;
	}

	if (!ignored) {
	    last_ch = ch;
	    count++;
	}
	ignored = FALSE;

	if (count > MAXCAPLEN && !long_warning) {
	    _nc_warning("Very long string found.  Missing separator?");
	    long_warning = TRUE;
	}
    }				/* end while */

    *ptr = '\0';

    return (ch);
}

/*
 *	_nc_push_token()
 *
 *	Push a token of given type so that it will be reread by the next
 *	get_token() call.
 */

NCURSES_EXPORT(void)
_nc_push_token(int tokclass)
{
    /*
     * This implementation is kind of bogus, it will fail if we ever do more
     * than one pushback at a time between get_token() calls.  It relies on the
     * fact that _nc_curr_token is static storage that nothing but
     * _nc_get_token() touches.
     */
    pushtype = tokclass;
    if (pushname == 0)
	pushname = typeMalloc(char, MAX_NAME_SIZE + 1);
    _nc_get_type(pushname);

    DEBUG(3, ("pushing token: `%s', class %d",
	      _nc_curr_token.tk_name, pushtype));
}

/*
 * Panic mode error recovery - skip everything until a "ch" is found.
 */
NCURSES_EXPORT(void)
_nc_panic_mode(char ch)
{
    int c;

    for (;;) {
	c = next_char();
	if (c == ch)
	    return;
	if (c == EOF)
	    return;
    }
}

/*****************************************************************************
 *
 * Character-stream handling
 *
 *****************************************************************************/

#define LEXBUFSIZ	1024

static char *bufptr;		/* otherwise, the input buffer pointer */
static char *bufstart;		/* start of buffer so we can compute offsets */
static FILE *yyin;		/* scanner's input file descriptor */

/*
 *	_nc_reset_input()
 *
 *	Resets the input-reading routines.  Used on initialization,
 *	or after a seek has been done.  Exactly one argument must be
 *	non-null.
 */

NCURSES_EXPORT(void)
_nc_reset_input(FILE *fp, char *buf)
{
    pushtype = NO_PUSHBACK;
    if (pushname != 0)
	pushname[0] = '\0';
    yyin = fp;
    bufstart = bufptr = buf;
    _nc_curr_file_pos = 0L;
    if (fp != 0)
	_nc_curr_line = 0;
    _nc_curr_col = 0;
}

/*
 *	int last_char()
 *
 *	Returns the final nonblank character on the current input buffer
 */
static int
last_char(void)
{
    size_t len = strlen(bufptr);
    while (len--) {
	if (!isspace(UChar(bufptr[len])))
	    return bufptr[len];
    }
    return 0;
}

/*
 *	int next_char()
 *
 *	Returns the next character in the input stream.  Comments and leading
 *	white space are stripped.
 *
 *	The global state variable 'firstcolumn' is set TRUE if the character
 *	returned is from the first column of the input line.
 *
 *	The global variable _nc_curr_line is incremented for each new line.
 *	The global variable _nc_curr_file_pos is set to the file offset of the
 *	beginning of each line.
 */

static int
next_char(void)
{
    if (!yyin) {
	/*
	 * An string with an embedded null will truncate the input.  This is
	 * intentional (we don't read binary files here).
	 */
	if (*bufptr == '\0')
	    return (EOF);
	if (*bufptr == '\n') {
	    _nc_curr_line++;
	    _nc_curr_col = 0;
	}
    } else if (!bufptr || !*bufptr) {
	/*
	 * In theory this could be recoded to do its I/O one character at a
	 * time, saving the buffer space.  In practice, this turns out to be
	 * quite hard to get completely right.  Try it and see.  If you
	 * succeed, don't forget to hack push_back() correspondingly.
	 */
	static char *result;
	static size_t allocated;
	size_t used;
	size_t len;

	do {
	    bufstart = 0;
	    used = 0;
	    do {
		if (used + (LEXBUFSIZ / 4) >= allocated) {
		    allocated += (allocated + LEXBUFSIZ);
		    result = typeRealloc(char, allocated, result);
		    if (result == 0)
			return (EOF);
		}
		if (used == 0)
		    _nc_curr_file_pos = ftell(yyin);

		if (fgets(result + used, allocated - used, yyin) != 0) {
		    bufstart = result;
		    if (used == 0) {
			_nc_curr_line++;
			_nc_curr_col = 0;
		    }
		} else {
		    if (used != 0)
			strcat(result, "\n");
		}
		if ((bufptr = bufstart) != 0) {
		    used = strlen(bufptr);
		    while (iswhite(*bufptr))
			bufptr++;

		    /*
		     * Treat a trailing <cr><lf> the same as a <newline> so we
		     * can read files on OS/2, etc.
		     */
		    if ((len = strlen(bufptr)) > 1) {
			if (bufptr[len - 1] == '\n'
			    && bufptr[len - 2] == '\r') {
			    len--;
			    bufptr[len - 1] = '\n';
			    bufptr[len] = '\0';
			}
		    }
		} else {
		    return (EOF);
		}
	    } while (bufptr[len - 1] != '\n');	/* complete a line */
	} while (result[0] == '#');	/* ignore comments */
    }

    first_column = (bufptr == bufstart);
    if (first_column)
	had_newline = FALSE;

    _nc_curr_col++;
    return (*bufptr++);
}

static void
push_back(char c)
/* push a character back onto the input stream */
{
    if (bufptr == bufstart)
	_nc_syserr_abort("Can't backspace off beginning of line");
    *--bufptr = c;
}

static long
stream_pos(void)
/* return our current character position in the input stream */
{
    return (yyin ? ftell(yyin) : (bufptr ? bufptr - bufstart : 0));
}

static bool
end_of_stream(void)
/* are we at end of input? */
{
    return ((yyin ? feof(yyin) : (bufptr && *bufptr == '\0'))
	    ? TRUE : FALSE);
}