emacs.c

一个开放源代码的 AT&T 的 Korn Shell 的复制品, 支持大多数 ksh89 的特性。

	int col = xcp - xbuf;

	if (col == 0)  {
		x_e_putc(BEL);
		return KSTD;
	}
	if (x_arg > col)
		x_arg = col;
	x_goto(xcp - x_arg);
	return KSTD;
}

static int
x_mv_forw(c)
	int c;
{
	int nleft = xep - xcp;

	if (!nleft) {
		x_e_putc(BEL);
		return KSTD;
	}
	if (x_arg > nleft)
		x_arg = nleft;
	x_goto(xcp + x_arg);
	return KSTD;
}

static int
x_search_char_forw(c)
	int c;
{
	char *cp = xcp;

	*xep = '\0';
	c = x_e_getc();
	while (x_arg--) {
	    if (c < 0
	       || ((cp = (cp == xep) ? NULL : strchr(cp + 1, c)) == NULL
		   && (cp = strchr(xbuf, c)) == NULL))
	    {
		    x_e_putc(BEL);
		    return KSTD;
	    }
	}
	x_goto(cp);
	return KSTD;
}

static int
x_search_char_back(c)
	int c;
{
	char *cp = xcp, *p;

	c = x_e_getc();
	for (; x_arg--; cp = p)
		for (p = cp; ; ) {
			if (p-- == xbuf)
				p = xep;
			if (c < 0 || p == cp) {
				x_e_putc(BEL);
				return KSTD;
			}
			if (*p == c)
				break;
		}
	x_goto(cp);
	return KSTD;
}

static int
x_newline(c)
	int c;
{
	x_e_putc('\r');
	x_e_putc('\n');
	x_flush();
	*xep++ = '\n';
	return KEOL;
}

static int
x_end_of_text(c)
	int c;
{
	return KEOL;
}

static int x_beg_hist(c) int c; { x_load_hist(history); return KSTD;}

static int x_end_hist(c) int c; { x_load_hist(histptr); return KSTD;}

static int x_prev_com(c) int c; { x_load_hist(x_histp - x_arg); return KSTD;}

static int x_next_com(c) int c; { x_load_hist(x_histp + x_arg); return KSTD;}
  
/* Goto a particular history number obtained from argument.
 * If no argument is given history 1 is probably not what you
 * want so we'll simply go to the oldest one.
 */
static int
x_goto_hist(c)
	int c;
{
	if (x_arg_defaulted)
		x_load_hist(history);
	else
		x_load_hist(histptr + x_arg - source->line);
	return KSTD;
}

static void
x_load_hist(hp)
	register char **hp;
{
	int	oldsize;

	if (hp < history || hp > histptr) {
		x_e_putc(BEL);
		return;
	}
	x_histp = hp;
	oldsize = x_size_str(xbuf);
	(void)strcpy(xbuf, *hp);
	xbp = xbuf;
	xep = xcp = xbuf + strlen(*hp);
	xlp_valid = FALSE;
	if (xep > x_lastcp())
	  x_goto(xep);
	else
	  x_redraw(oldsize);
}

static int
x_nl_next_com(c)
	int	c;
{
	x_nextcmd = source->line - (histptr - x_histp) + 1;
	return (x_newline(c));
}

static int
x_eot_del(c)
	int	c;
{
	if (xep == xbuf && x_arg_defaulted)
		return (x_end_of_text(c));
	else
		return (x_del_char(c));
}

/* reverse incremental history search */
static int
x_search_hist(c)
	int c;
{
	int offset = -1;	/* offset of match in xbuf, else -1 */
	char pat [256+1];	/* pattern buffer */
	register char *p = pat;
	Findex f;

	*p = '\0';
	while (1) {
		if (offset < 0) {
			x_e_puts("\nI-search: ");
			x_e_puts(pat);
		}
		x_flush();
		if ((c = x_e_getc()) < 0)
			return KSTD;
		f = x_tab[0][c&CHARMASK];
		if (c == CTRL('['))
			break;
		else if (f == XFUNC_search_hist)
			offset = x_search(pat, 0, offset);
		else if (f == XFUNC_del_back) {
			if (p == pat) {
				offset = -1;
				break;
			}
			if (p > pat)
				*--p = '\0';
			if (p == pat)
				offset = -1;
			else
				offset = x_search(pat, 1, offset);
			continue;
		} else if (f == XFUNC_insert) {
			/* add char to pattern */
			/* overflow check... */
			if (p >= &pat[sizeof(pat) - 1]) {
				x_e_putc(BEL);
				continue;
			}
			*p++ = c, *p = '\0';
			if (offset >= 0) {
				/* already have partial match */
				offset = x_match(xbuf, pat);
				if (offset >= 0) {
					x_goto(xbuf + offset + (p - pat) - (*pat == '^'));
					continue;
				}
			}
			offset = x_search(pat, 0, offset);
		} else { /* other command */
			x_e_ungetc(c);
			break;
		}
	}
	if (offset < 0)
		x_redraw(-1);
	return KSTD;
}

/* search backward from current line */
static int
x_search(pat, sameline, offset)
	char *pat;
	int sameline;
	int offset;
{
	register char **hp;
	int i;

	for (hp = x_histp - (sameline ? 0 : 1) ; hp >= history; --hp) {
		i = x_match(*hp, pat);
		if (i >= 0) {
			if (offset < 0)
				x_e_putc('\n');
			x_load_hist(hp);
			x_goto(xbuf + i + strlen(pat) - (*pat == '^'));
			return i;
		}
	}
	x_e_putc(BEL);
	x_histp = histptr;
	return -1;
}

/* return position of first match of pattern in string, else -1 */
static int
x_match(str, pat)
	char *str, *pat;
{
	if (*pat == '^') {
		return (strncmp(str, pat+1, strlen(pat+1)) == 0) ? 0 : -1;
	} else {
		char *q = strstr(str, pat);
		return (q == NULL) ? -1 : q - str;
	}
}

static int
x_del_line(c)
	int c;
{
	int	i, j;

	*xep = 0;
	i = xep- xbuf;
	j = x_size_str(xbuf);
	xcp = xbuf;
	x_push(i);
	xlp = xbp = xep = xbuf;
	xlp_valid = TRUE;
	*xcp = 0;
	xmp = NULL;
	x_redraw(j);
	return KSTD;
}

static int
x_mv_end(c)
	int c;
{
	x_goto(xep);
	return KSTD;
}

static int
x_mv_begin(c)
	int c;
{
	x_goto(xbuf);
	return KSTD;
}

static int
x_draw_line(c)
	int c;
{
	x_redraw(-1);
	return KSTD;

}

/* Redraw (part of) the line.  If limit is < 0, the everything is redrawn
 * on a NEW line, otherwise limit is the screen column up to which needs
 * redrawing.
 */
static void
x_redraw(limit)
  int limit;
{
	int	i, j;
	char	*cp;
	
	x_adj_ok = 0;
	if (limit == -1)
		x_e_putc('\n');
	else 
		x_e_putc('\r');
	x_flush();
	if (xbp == xbuf)
	{
	  pprompt(prompt + prompt_skip, 0);
	  x_col = promptlen(prompt, (const char **) 0);
	}
	x_displen = xx_cols - 2 - x_col;
	xlp_valid = FALSE;
	cp = x_lastcp();
	x_zots(xbp);
	if (xbp != xbuf || xep > xlp)
	  limit = xx_cols;
	if (limit >= 0)
	{
	  if (xep > xlp)
	    i = 0;			/* we fill the line */
	  else
	    i = limit - (xlp - xbp);

	  for (j = 0; j < i && x_col < (xx_cols - 2); j++)
	    x_e_putc(' ');
	  i = ' ';
	  if (xep > xlp)		/* more off screen */
	  {
	    if (xbp > xbuf)
	      i = '*';
	    else
	      i = '>';
	  }
	  else
	    if (xbp > xbuf)
	      i = '<';
	  x_e_putc(i);
	  j++;
	  while (j--)
	    x_e_putc('\b');
	}
	for (cp = xlp; cp > xcp; )
	  x_bs(*--cp);
	x_adj_ok = 1;
	D__(x_flush();)
	return;
}

static int
x_transpose(c)
	int c;
{
	char	tmp;

	/* What transpose is meant to do seems to be up for debate. This
	 * is a general summary of the options; the text is abcd with the
	 * upper case character or underscore indicating the cursor positiion:
	 *     Who			Before	After  Before	After
	 *     at&t ksh in emacs mode:	abCd	abdC   abcd_	(bell)
	 *     at&t ksh in gmacs mode:	abCd	baCd   abcd_	abdc_
	 *     gnu emacs:		abCd	acbD   abcd_	abdc_
	 * Pdksh currently goes with GNU behavior since I believe this is the
	 * most common version of emacs, unless in gmacs mode, in which case
	 * it does the at&t ksh gmacs mdoe.
	 * This should really be broken up into 3 functions so users can bind
	 * to the one they want.
	 */
	if (xcp == xbuf) {
		x_e_putc(BEL);
		return KSTD;
	} else if (xcp == xep || Flag(FGMACS)) {
		if (xcp - xbuf == 1) {
			x_e_putc(BEL);
			return KSTD;
		}
		/* Gosling/Unipress emacs style: Swap two characters before the
		 * cursor, do not change cursor position
		 */
		x_bs(xcp[-1]);
		x_bs(xcp[-2]);
		x_zotc(xcp[-1]);
		x_zotc(xcp[-2]);
		tmp = xcp[-1];
		xcp[-1] = xcp[-2];
		xcp[-2] = tmp;
	} else {
		/* GNU emacs style: Swap the characters before and under the
		 * cursor, move cursor position along one.
		 */
		x_bs(xcp[-1]);
		x_zotc(xcp[0]);
		x_zotc(xcp[-1]);
		tmp = xcp[-1];
		xcp[-1] = xcp[0];
		xcp[0] = tmp;
		x_bs(xcp[0]);
		x_goto(xcp + 1);
	}
	return KSTD;
}

static int
x_literal(c)
	int c;
{
	x_curprefix = -1;
	return KSTD;
}

static int
x_meta1(c)
	int c;
{
	x_curprefix = 1;
	return KSTD;
}

static int
x_meta2(c)
	int c;
{
	x_curprefix = 2;
	return KSTD;
}

#ifdef OS2
static int
x_meta3(c)
	int c;
{
	x_curprefix = 3;
	return KSTD;
}
#endif /* OS2 */

static int
x_kill(c)
	int c;
{
	int col = xcp - xbuf;
	int lastcol = xep - xbuf;
	int ndel;

	if (x_arg_defaulted)
		x_arg = lastcol;
	else if (x_arg > lastcol)
		x_arg = lastcol;
	ndel = x_arg - col;
	if (ndel < 0) {
		x_goto(xbuf + x_arg);
		ndel = -ndel;
	}
	x_delete(ndel, TRUE);
	return KSTD;
}

static void
x_push(nchars)
	int nchars;
{
	char	*cp = str_nsave(xcp, nchars, AEDIT);
	if (killstack[killsp])
		afree((void *)killstack[killsp], AEDIT);
	killstack[killsp] = cp;
	killsp = (killsp + 1) % KILLSIZE;
}

static int
x_yank(c)
	int c;
{
	if (killsp == 0)
		killtp = KILLSIZE;
	else
		killtp = killsp;
	killtp --;
	if (killstack[killtp] == 0)  {
		x_e_puts("\nnothing to yank");
		x_redraw(-1);
		return KSTD;
	}
	xmp = xcp;
	x_ins(killstack[killtp]);
	return KSTD;
}

static int
x_meta_yank(c)
	int c;
{
	int	len;
	if (x_last_command != XFUNC_yank && x_last_command != XFUNC_meta_yank) {
		x_e_puts("\nyank something first");
		x_redraw(-1);
		return KSTD;
	}
	len = strlen(killstack[killtp]);
	x_goto(xcp - len);
	x_delete(len, FALSE);
	do {
		if (killtp == 0)
			killtp = KILLSIZE - 1;
		else
			killtp--;
	} while (killstack[killtp] == 0);
	x_ins(killstack[killtp]);
	return KSTD;
}

static int
x_abort(c)
	int c;
{
	/* x_zotc(c); */
	xlp = xep = xcp = xbp = xbuf;
	xlp_valid = TRUE;
	*xcp = 0;
	return KINTR;
}

static int
x_error(c)
	int c;
{
	x_e_putc(BEL);
	return KSTD;
}

static int
x_stuffreset(c)
	int c;
{
#ifdef TIOCSTI
	(void)x_stuff(c);
	return KINTR;
#else
	x_zotc(c);
	xlp = xcp = xep = xbp = xbuf;
	xlp_valid = TRUE;
	*xcp = 0;
	x_redraw(-1);
	return KSTD;
#endif
}

static int
x_stuff(c)
	int c;
{
#if 0 || defined TIOCSTI
	char	ch = c;
	bool_t	savmode = x_mode(FALSE);

	(void)ioctl(TTY, TIOCSTI, &ch);
	(void)x_mode(savmode);
	x_redraw(-1);
#endif
	return KSTD;
}

static char *
x_mapin(cp)
	const char *cp;
{
	char *new, *op;

	op = new = str_save(cp, ATEMP);
	while (*cp)  {
		/* XXX -- should handle \^ escape? */
		if (*cp == '^')  {
			cp++;
#ifdef OS2
			if (*cp == '0')	/* To define function keys */
				*op++ = 0xE0;
			else
#endif /* OS2 */
			if (*cp >= '?')	/* includes '?'; ASCII */
				*op++ = CTRL(*cp);
			else  {
				*op++ = '^';
				cp--;
			}
		} else
			*op++ = *cp;
		cp++;
	}
	*op = '\0';

	return new;
}

static char *
x_mapout(c)
	int c;
{
	static char buf[8];
	register char *p = buf;

#ifdef OS2
	if (c == 0xE0) {
		*p++ = '^';
		*p++ = '0';
	} else
#endif /* OS2 */
	if (iscntrl(c))  {
		*p++ = '^';
		*p++ = UNCTRL(c);
	} else
		*p++ = c;
	*p = 0;
	return buf;
}

static void
x_print(prefix, key)
	int prefix, key;
{
	if (prefix == 1)
		shprintf("%s", x_mapout(x_prefix1));
	if (prefix == 2)
		shprintf("%s", x_mapout(x_prefix2));
#ifdef OS2
	if (prefix == 3)
		shprintf("%s", x_mapout(x_prefix3));
#endif /* OS2 */
	shprintf("%s = ", x_mapout(key));
	if (x_tab[prefix][key] != XFUNC_ins_string)
		shprintf("%s\n", x_ftab[x_tab[prefix][key]].xf_name);
	else
		shprintf("'%s'\n", x_atab[prefix][key]);
}

int
x_bind(a1, a2, macro, list)
	const char *a1, *a2;
	int macro;		/* bind -m */
	int list;		/* bind -l */
{
	Findex f;
	int prefix, key;
	char *sp = NULL;
	char *m1, *m2;

	if (x_tab == NULL) {
		bi_errorf("cannot bind, not a tty");
		return 1;
	}

	/* List function names */
	if (list) {
		for (f = 0; f < NELEM(x_ftab); f++)
			if (x_ftab[f].xf_name
			    && !(x_ftab[f].xf_flags & XF_NOBIND))
				shprintf("%s\n", x_ftab[f].xf_name);
		return 0;
	}

	if (a1 == NULL) {
		for (prefix = 0; prefix < X_NTABS; prefix++)
			for (key = 0; key < X_TABSZ; key++) {
				f = x_tab[prefix][key];
				if (f == XFUNC_insert || f == XFUNC_error
				    || (macro && f != XFUNC_ins_string))
					continue;
				x_print(prefix, key);
			}
		return 0;
	}

	m1 = x_mapin(a1);
	prefix = key = 0;
	for (;; m1++) {
		key = *m1 & CHARMASK;
		if (x_tab[prefix][key] == XFUNC_meta1)
			prefix = 1;
		else if (x_tab[prefix][key] == XFUNC_meta2)
			prefix = 2;
#ifdef OS2
		else if (x_tab[prefix][key] == XFUNC_meta3)
			prefix = 3;
#endif /* OS2 */
		else
			break;
	}

	if (a2 == NULL) {
		x_print(prefix, key);
		return 0;
	}

	if (*a2 == 0)
		f = XFUNC_insert;
	else if (!macro) {
		for (f = 0; f < NELEM(x_ftab); f++)
			if (x_ftab[f].xf_name
			    && strcmp(x_ftab[f].xf_name, a2) == 0)
				break;
		if (f == NELEM(x_ftab) || x_ftab[f].xf_flags & XF_NOBIND) {
			bi_errorf("%s: no such function", a2);
			return 1;
		}
#if 0		/* This breaks the bind commands that map arrow keys */
		if (f == XFUNC_meta1)
			x_prefix1 = key;
		if (f == XFUNC_meta2)
			x_prefix2 = key;
#endif /* 0 */
	} else {
		f = XFUNC_ins_string;
		m2 = x_mapin(a2);
		sp = str_save(m2, AEDIT);
	}

	if (x_tab[prefix][key] == XFUNC_ins_string && x_atab[prefix][key])
		afree((void *)x_atab[prefix][key], AEDIT);
	x_tab[prefix][key] = f;
	x_atab[prefix][key] = sp;

	/* Track what the user has bound so x_emacs_keys() won't toast things */
	if (f == XFUNC_insert)
		x_bound[(prefix * X_TABSZ + key) / 8] &=
			~(1 << ((prefix * X_TABSZ + key) % 8));
	else
		x_bound[(prefix * X_TABSZ + key) / 8] |=
			(1 << ((prefix * X_TABSZ + key) % 8));