more.c

早期freebsd实现

		}
		switch (*fmt++) {
		case 'd':
			ccount += printd (va_arg(ap, int));
			break;
		case 's':
			ccount += pr (va_arg(ap, char *));
			break;
		case '%':
			ccount++;
			putchar ('%');
			break;
		case '0':
			return (ccount);
		default:
			break;
		}
	}
	va_end(ap);
	return (ccount);

}

/*
** Print an integer as a string of decimal digits,
** returning the length of the print representation.
*/

printd (n)
int n;
{
    int a, nchars;

    if (a = n/10)
	nchars = 1 + printd(a);
    else
	nchars = 1;
    putchar (n % 10 + '0');
    return (nchars);
}

/* Put the print representation of an integer into a string */
static char *sptr;

scanstr (n, str)
int n;
char *str;
{
    sptr = str;
    Sprintf (n);
    *sptr = '\0';
}

Sprintf (n)
{
    int a;

    if (a = n/10)
	Sprintf (a);
    *sptr++ = n % 10 + '0';
}

static char bell = ctrl('G');

/* See whether the last component of the path name "path" is equal to the
** string "string"
*/

tailequ (path, string)
char *path;
register char *string;
{
	register char *tail;

	tail = path + strlen(path);
	while (tail >= path)
		if (*(--tail) == '/')
			break;
	++tail;
	while (*tail++ == *string++)
		if (*tail == '\0')
			return(1);
	return(0);
}

prompt (filename)
char *filename;
{
    if (clreol)
	cleareol ();
    else if (promptlen > 0)
	kill_line ();
    if (!hard) {
	promptlen = 8;
	if (Senter && Sexit) {
	    tputs (Senter, 1, putch);
	    promptlen += (2 * soglitch);
	}
	if (clreol)
	    cleareol ();
	pr("--More--");
	if (filename != NULL) {
	    promptlen += prtf ("(Next file: %s)", filename);
	}
	else if (!no_intty) {
	    promptlen += prtf ("(%d%%)", (int)((file_pos * 100) / file_size));
	}
	if (dum_opt) {
	    promptlen += pr("[Press space to continue, 'q' to quit.]");
	}
	if (Senter && Sexit)
	    tputs (Sexit, 1, putch);
	if (clreol)
	    clreos ();
	fflush(stdout);
    }
    else
	write (2, &bell, 1);
    inwait++;
}

/*
** Get a logical line
*/

getline(f, length)
register FILE *f;
int *length;
{
    register int	c;
    register char	*p;
    register int	column;
    static int		colflg;

    p = Line;
    column = 0;
    c = Getc (f);
    if (colflg && c == '\n') {
	Currline++;
	c = Getc (f);
    }
    while (p < &Line[LINSIZ - 1]) {
	if (c == EOF) {
	    if (p > Line) {
		*p = '\0';
		*length = p - Line;
		return (column);
	    }
	    *length = p - Line;
	    return (EOF);
	}
	if (c == '\n') {
	    Currline++;
	    break;
	}
	*p++ = c;
	if (c == '\t')
	    if (!hardtabs || column < promptlen && !hard) {
		if (hardtabs && eraseln && !dumb) {
		    column = 1 + (column | 7);
		    tputs (eraseln, 1, putch);
		    promptlen = 0;
		}
		else {
		    for (--p; p < &Line[LINSIZ - 1];) {
			*p++ = ' ';
			if ((++column & 7) == 0)
			    break;
		    }
		    if (column >= promptlen) promptlen = 0;
		}
	    }
	    else
		column = 1 + (column | 7);
	else if (c == '\b' && column > 0)
	    column--;
	else if (c == '\r')
	    column = 0;
	else if (c == '\f' && stop_opt) {
		p[-1] = '^';
		*p++ = 'L';
		column += 2;
		Pause++;
	}
	else if (c == EOF) {
	    *length = p - Line;
	    return (column);
	}
	else if (c >= ' ' && c != RUBOUT)
	    column++;
	if (column >= Mcol && fold_opt) break;
	c = Getc (f);
    }
    if (column >= Mcol && Mcol > 0) {
	if (!Wrap) {
	    *p++ = '\n';
	}
    }
    colflg = column == Mcol && fold_opt;
    if (colflg && eatnl && Wrap) {
	*p++ = '\n'; /* simulate normal wrap */
    }
    *length = p - Line;
    *p = 0;
    return (column);
}

/*
** Erase the rest of the prompt, assuming we are starting at column col.
*/

erase (col)
register int col;
{

    if (promptlen == 0)
	return;
    if (hard) {
	putchar ('\n');
    }
    else {
	if (col == 0)
	    putchar ('\r');
	if (!dumb && eraseln)
	    tputs (eraseln, 1, putch);
	else
	    for (col = promptlen - col; col > 0; col--)
		putchar (' ');
    }
    promptlen = 0;
}

/*
** Erase the current line entirely
*/

kill_line ()
{
    erase (0);
    if (!eraseln || dumb) putchar ('\r');
}

/*
 * force clear to end of line
 */
cleareol()
{
    tputs(eraseln, 1, putch);
}

clreos()
{
    tputs(EodClr, 1, putch);
}

/*
**  Print string and return number of characters
*/

pr(s1)
char	*s1;
{
    register char	*s;
    register char	c;

    for (s = s1; c = *s++; )
	putchar(c);
    return (s - s1 - 1);
}


/* Print a buffer of n characters */

prbuf (s, n)
register char *s;
register int n;
{
    register char c;			/* next output character */
    register int state;			/* next output char's UL state */
#define wouldul(s,n)	((n) >= 2 && (((s)[0] == '_' && (s)[1] == '\b') || ((s)[1] == '\b' && (s)[2] == '_')))

    while (--n >= 0)
	if (!ul_opt)
	    putchar (*s++);
	else {
	    if (*s == ' ' && pstate == 0 && ulglitch && wouldul(s+1, n-1)) {
		s++;
		continue;
	    }
	    if (state = wouldul(s, n)) {
		c = (*s == '_')? s[2] : *s ;
		n -= 2;
		s += 3;
	    } else
		c = *s++;
	    if (state != pstate) {
		if (c == ' ' && state == 0 && ulglitch && wouldul(s, n-1))
		    state = 1;
		else
		    tputs(state ? ULenter : ULexit, 1, putch);
	    }
	    if (c != ' ' || pstate == 0 || state != 0 || ulglitch == 0)
	        putchar(c);
	    if (state && *chUL) {
		pr(chBS);
		tputs(chUL, 1, putch);
	    }
	    pstate = state;
	}
}

/*
**  Clear the screen
*/

doclear()
{
    if (Clear && !hard) {
	tputs(Clear, 1, putch);

	/* Put out carriage return so that system doesn't
	** get confused by escape sequences when expanding tabs
	*/
	putchar ('\r');
	promptlen = 0;
    }
}

/*
 * Go to home position
 */
home()
{
    tputs(Home,1,putch);
}

static int lastcmd, lastarg, lastp;
static int lastcolon;
char shell_line[132];

/*
** Read a command and do it. A command consists of an optional integer
** argument followed by the command character.  Return the number of lines
** to display in the next screenful.  If there is nothing more to display
** in the current file, zero is returned.
*/

command (filename, f)
char *filename;
register FILE *f;
{
    register int nlines;
    register int retval;
    register char c;
    char colonch;
    FILE *helpf;
    int done;
    char comchar, cmdbuf[80], *p;

#define ret(val) retval=val;done++;break

    done = 0;
    if (!errors)
	prompt (filename);
    else
	errors = 0;
    if (MBIT == RAW && slow_tty) {
	otty.sg_flags |= MBIT;
	stty(fileno(stderr), &otty);
    }
    for (;;) {
	nlines = number (&comchar);
	lastp = colonch = 0;
	if (comchar == '.') {	/* Repeat last command */
		lastp++;
		comchar = lastcmd;
		nlines = lastarg;
		if (lastcmd == ':')
			colonch = lastcolon;
	}
	lastcmd = comchar;
	lastarg = nlines;
	if (comchar == otty.sg_erase) {
	    kill_line ();
	    prompt (filename);
	    continue;
	}
	switch (comchar) {
	case ':':
	    retval = colon (filename, colonch, nlines);
	    if (retval >= 0)
		done++;
	    break;
	case 'b':
	case ctrl('B'):
	    {
		register int initline;

		if (no_intty) {
		    write(2, &bell, 1);
		    return (-1);
		}

		if (nlines == 0) nlines++;

		putchar ('\r');
		erase (0);
		prtf ("\n");
		if (clreol)
			cleareol ();
		prtf ("...back %d page", nlines);
		if (nlines > 1)
			pr ("s\n");
		else
			pr ("\n");

		if (clreol)
			cleareol ();
		pr ("\n");

		initline = Currline - dlines * (nlines + 1);
		if (! noscroll)
		    --initline;
		if (initline < 0) initline = 0;
		Fseek(f, 0L);
		Currline = 0;	/* skiplns() will make Currline correct */
		skiplns(initline, f);
		if (! noscroll) {
		    ret(dlines + 1);
		}
		else {
		    ret(dlines);
		}
	    }
	case ' ':
	case 'z':
	    if (nlines == 0) nlines = dlines;
	    else if (comchar == 'z') dlines = nlines;
	    ret (nlines);
	case 'd':
	case ctrl('D'):
	    if (nlines != 0) nscroll = nlines;
	    ret (nscroll);
	case 'q':
	case 'Q':
	    end_it ();
	case 's':
	case 'f':
	    if (nlines == 0) nlines++;
	    if (comchar == 'f')
		nlines *= dlines;
	    putchar ('\r');
	    erase (0);
	    prtf ("\n");
	    if (clreol)
		cleareol ();
	    prtf ("...skipping %d line", nlines);
	    if (nlines > 1)
		pr ("s\n");
	    else
		pr ("\n");

	    if (clreol)
		cleareol ();
	    pr ("\n");

	    while (nlines > 0) {
		while ((c = Getc (f)) != '\n')
		    if (c == EOF) {
			retval = 0;
			done++;
			goto endsw;
		    }
		    Currline++;
		    nlines--;
	    }
	    ret (dlines);
	case '\n':
	    if (nlines != 0)
		dlines = nlines;
	    else
		nlines = 1;
	    ret (nlines);
	case '\f':
	    if (!no_intty) {
		doclear ();
		Fseek (f, screen_start.chrctr);
		Currline = screen_start.line;
		ret (dlines);
	    }
	    else {
		write (2, &bell, 1);
		break;
	    }
	case '\'':
	    if (!no_intty) {
		kill_line ();
		pr ("\n***Back***\n\n");
		Fseek (f, context.chrctr);
		Currline = context.line;
		ret (dlines);
	    }
	    else {
		write (2, &bell, 1);
		break;
	    }
	case '=':
	    kill_line ();
	    promptlen = printd (Currline);
	    fflush (stdout);
	    break;
	case 'n':
	    lastp++;
	case '/':
	    if (nlines == 0) nlines++;
	    kill_line ();
	    pr ("/");
	    promptlen = 1;
	    fflush (stdout);
	    if (lastp) {
		write (2,"\r", 1);
		search (NULL, f, nlines);	/* Use previous r.e. */
	    }
	    else {
		ttyin (cmdbuf, 78, '/');
		write (2, "\r", 1);
		search (cmdbuf, f, nlines);
	    }
	    ret (dlines-1);
	case '!':
	    do_shell (filename);
	    break;
	case '?':
	case 'h':
	    if ((helpf = fopen (HELPFILE, "r")) == NULL)
		error ("Can't open help file");
	    if (noscroll) doclear ();
	    copy_file (helpf);
	    fclose (helpf);
	    prompt (filename);
	    break;
	case 'v':	/* This case should go right before default */
	    if (!no_intty) {
		kill_line ();
		cmdbuf[0] = '+';
		scanstr (Currline - dlines < 0 ? 0
				: Currline - (dlines + 1) / 2, &cmdbuf[1]);
		pr ("vi "); pr (cmdbuf); putchar (' '); pr (fnames[fnum]);
		execute (filename, _PATH_VI, "vi", cmdbuf, fnames[fnum], 0);
		break;
	    }
	default:
	    if (dum_opt) {
   		kill_line ();
		if (Senter && Sexit) {
		    tputs (Senter, 1, putch);
		    promptlen = pr ("[Press 'h' for instructions.]") + (2 * soglitch);
		    tputs (Sexit, 1, putch);
		}
		else
		    promptlen = pr ("[Press 'h' for instructions.]");
		fflush (stdout);
	    }
	    else
		write (2, &bell, 1);
	    break;
	}
	if (done) break;
    }
    putchar ('\r');
endsw:
    inwait = 0;
    notell++;
    if (MBIT == RAW && slow_tty) {
	otty.sg_flags &= ~MBIT;
	stty(fileno(stderr), &otty);
    }
    return (retval);
}

char ch;

/*
 * Execute a colon-prefixed command.
 * Returns <0 if not a command that should cause
 * more of the file to be printed.
 */

colon (filename, cmd, nlines)
char *filename;
int cmd;
int nlines;
{
	if (cmd == 0)
		ch = readch ();
	else
		ch = cmd;
	lastcolon = ch;
	switch (ch) {
	case 'f':
		kill_line ();
		if (!no_intty)
			promptlen = prtf ("\"%s\" line %d", fnames[fnum], Currline);
		else
			promptlen = prtf ("[Not a file] line %d", Currline);
		fflush (stdout);
		return (-1);
	case 'n':
		if (nlines == 0) {
			if (fnum >= nfiles - 1)
				end_it ();
			nlines++;
		}