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。

/*
 *  Emacs-like command line editing and history
 *
 *  created by Ron Natalie at BRL
 *  modified by Doug Kingston, Doug Gwyn, and Lou Salkind
 *  adapted to PD ksh by Eric Gisin
 */

#include "config.h"
#ifdef EMACS

#include "sh.h"
#include "ksh_stat.h"
#include "ksh_dir.h"
#include <ctype.h>
#include "edit.h"

static	Area	aedit;
#define	AEDIT	&aedit		/* area for kill ring and macro defns */

#undef CTRL			/* _BSD brain damage */
#define	CTRL(x)		((x) == '?' ? 0x7F : (x) & 0x1F)	/* ASCII */
#define	UNCTRL(x)	((x) == 0x7F ? '?' : (x) | 0x40)	/* ASCII */


/* values returned by keyboard functions */
#define	KSTD	0
#define	KEOL	1		/* ^M, ^J */
#define	KINTR	2		/* ^G, ^C */

struct	x_ftab  {
	int		(*xf_func) ARGS((int c));
	const char	*xf_name;
	short		xf_flags;
};

/* index into struct x_ftab x_ftab[] - small is good */
typedef unsigned char Findex;

struct x_defbindings {
	Findex		xdb_func;	/* XFUNC_* */
	unsigned char	xdb_tab;
	unsigned char	xdb_char;
};

#define XF_ARG		1	/* command takes number prefix */
#define	XF_NOBIND	2	/* not allowed to bind to function */
#define	XF_PREFIX	4	/* function sets prefix */

/* Separator for completion */
#define	is_cfs(c)	(c == ' ' || c == '\t' || c == '"' || c == '\'')
#define	is_mfs(c)	(!(isalnum(c) || c == '_' || c == '$'))  /* Separator for motion */

#ifdef OS2
  /* Deal with 8 bit chars & an extra prefix for function key (these two
   * changes increase memory usage from 9,216 bytes to 24,416 bytes...)
   */
# define CHARMASK	0xFF		/* 8-bit ASCII character mask */
# define X_NTABS	4		/* normal, meta1, meta2, meta3 */
static int	x_prefix3 = 0xE0;
#else /* OS2 */
# define CHARMASK	0xFF		/* 8-bit character mask */
# define X_NTABS	3		/* normal, meta1, meta2 */
#endif /* OS2 */
#define X_TABSZ		(CHARMASK+1)	/* size of keydef tables etc */

/* Arguments for do_complete()
 * 0 = enumerate  M-= complete as much as possible and then list
 * 1 = complete   M-Esc
 * 2 = list       M-?
 */
typedef enum { CT_LIST, 	/* list the possible completions */
		 CT_COMPLETE,	/* complete to longest prefix */
		 CT_COMPLIST	/* complete and then list (if non-exact) */
	} Comp_type;

/* { from 4.9 edit.h */
/*
 * The following are used for my horizontal scrolling stuff
 */
static char   *xbuf;		/* beg input buffer */
static char   *xend;		/* end input buffer */
static char    *xcp;		/* current position */
static char    *xep;		/* current end */
static char    *xbp;		/* start of visible portion of input buffer */
static char    *xlp;		/* last char visible on screen */
static int	x_adj_ok;
/*
 * we use x_adj_done so that functions can tell 
 * whether x_adjust() has been called while they are active.
 */
static int	x_adj_done;

static int	xx_cols;
static int	x_col;
static int	x_displen;
static int	x_arg;		/* general purpose arg */
static int	x_arg_defaulted;/* x_arg not explicitly set; defaulted to 1 */

static int	xlp_valid;
/* end from 4.9 edit.h } */

static	int	x_prefix1 = CTRL('['), x_prefix2 = CTRL('X');
static	char   **x_histp;	/* history position */
static	int	x_nextcmd;	/* for newline-and-next */
static	char	*xmp;		/* mark pointer */
static	Findex   x_last_command;
static	Findex (*x_tab)[X_TABSZ];	/* key definition */
static	char    *(*x_atab)[X_TABSZ];	/* macro definitions */
static	unsigned char	x_bound[(X_TABSZ * X_NTABS + 7) / 8];
#define	KILLSIZE	20
static	char    *killstack[KILLSIZE];
static	int	killsp, killtp;
static	int	x_curprefix;
static	char    *macroptr;
static	int	prompt_skip;

static int      x_ins       ARGS((char *cp));
static void     x_delete    ARGS((int nc, int force_push));
static int	x_bword     ARGS((void));
static int	x_fword     ARGS((void));
static void     x_goto      ARGS((char *cp));
static void     x_bs        ARGS((int c));
static int      x_size_str  ARGS((char *cp));
static int      x_size      ARGS((int c));
static void     x_zots      ARGS((char *str));
static void     x_zotc      ARGS((int c));
static void     x_load_hist ARGS((char **hp));
static int      x_search    ARGS((char *pat, int sameline, int offset));
static int      x_match     ARGS((char *str, char *pat));
static void	x_redraw    ARGS((int limit));
static void     x_push      ARGS((int nchars));
static char *   x_mapin     ARGS((const char *cp));
static char *   x_mapout    ARGS((int c));
static void     x_print     ARGS((int prefix, int key));
static void	x_adjust    ARGS((void));
static void	x_e_ungetc  ARGS((int c));
static int	x_e_getc    ARGS((void));
static void	x_e_putc    ARGS((int c));
static void	x_e_puts    ARGS((const char *s));
static int	x_fold_case ARGS((int c));
static char	*x_lastcp ARGS((void));
static void	do_complete ARGS((int flags, Comp_type type));


/* The lines between START-FUNC-TAB .. END-FUNC-TAB are run through a
 * script (emacs-gen.sh) that generates emacs.out which contains:
 *	- function declarations for x_* functions
 *	- defines of the form XFUNC_<name> where <name> is function
 *	  name, sans leading x_.
 * Note that the script treats #ifdef and { 0, 0, 0} specially - use with
 * caution.
 */
#include "emacs.out"
static const struct x_ftab x_ftab[] = {
/* @START-FUNC-TAB@ */
	{ x_abort,		"abort",			0 },
	{ x_beg_hist,		"beginning-of-history",		0 },
	{ x_comp_comm,		"complete-command",		0 },
	{ x_comp_file,		"complete-file",		0 },
	{ x_complete,		"complete",			0 },
	{ x_del_back,		"delete-char-backward",		XF_ARG },
	{ x_del_bword,		"delete-word-backward",		XF_ARG },
	{ x_del_char,		"delete-char-forward",		XF_ARG },
	{ x_del_fword,		"delete-word-forward",		XF_ARG },
	{ x_del_line,		"kill-line",			0 },
	{ x_draw_line,		"redraw",			0 },
	{ x_end_hist,		"end-of-history",		0 },
	{ x_end_of_text,	"eot",				0 },
	{ x_enumerate,		"list",				0 },
	{ x_eot_del,		"eot-or-delete",		XF_ARG },
	{ x_error,		"error",			0 },
	{ x_goto_hist,		"goto-history",			XF_ARG },
	{ x_ins_string,		"macro-string",			XF_NOBIND },
	{ x_insert,		"auto-insert",			XF_ARG },
	{ x_kill,		"kill-to-eol",			XF_ARG },
	{ x_kill_region,	"kill-region",			0 },
	{ x_list_comm,		"list-command",			0 },
	{ x_list_file,		"list-file",			0 },
	{ x_literal,		"quote",			0 },
	{ x_meta1,		"prefix-1",			XF_PREFIX },
	{ x_meta2,		"prefix-2",			XF_PREFIX },
	{ x_meta_yank,		"yank-pop",			0 },
	{ x_mv_back,		"backward-char",		XF_ARG },
	{ x_mv_begin,		"beginning-of-line",		0 },
	{ x_mv_bword,		"backward-word",		XF_ARG },
	{ x_mv_end,		"end-of-line",			0 },
	{ x_mv_forw,		"forward-char",			XF_ARG },
	{ x_mv_fword,		"forward-word",			XF_ARG },
	{ x_newline,		"newline",			0 },
	{ x_next_com,		"down-history",			XF_ARG },
	{ x_nl_next_com,	"newline-and-next",		0 },
	{ x_noop,		"no-op",			0 },
	{ x_prev_com,		"up-history",			XF_ARG },
	{ x_prev_histword,	"prev-hist-word",		XF_ARG },
	{ x_search_char_forw,	"search-character-forward",	XF_ARG },
	{ x_search_char_back,	"search-character-backward",	XF_ARG },
	{ x_search_hist,	"search-history",		0 },
	{ x_set_mark,		"set-mark-command",		0 },
	{ x_stuff,		"stuff",			0 },
	{ x_stuffreset,		"stuff-reset",			0 },
	{ x_transpose,		"transpose-chars",		0 },
	{ x_version,		"version",			0 },
	{ x_xchg_point_mark,	"exchange-point-and-mark",	0 },
	{ x_yank,		"yank",				0 },
        { x_comp_list,		"complete-list",		0 },
        { x_expand,		"expand-file",			0 },
        { x_fold_capitialize,	"capitalize-word",		XF_ARG },
        { x_fold_lower,		"downcase-word",		XF_ARG },
        { x_fold_upper,		"upcase-word",			XF_ARG },
        { x_set_arg,		"set-arg",			XF_NOBIND },
        { x_comment,		"comment",			0 },
#ifdef SILLY
	{ x_game_of_life,	"play-game-of-life",		0 },
#else
	{ 0, 0, 0 },
#endif
#ifdef DEBUG
        { x_debug_info,		"debug-info",			0 },
#else
	{ 0, 0, 0 },
#endif
#ifdef OS2
	{ x_meta3,		"prefix-3",			XF_PREFIX },
#else
	{ 0, 0, 0 },
#endif
/* @END-FUNC-TAB@ */
    };

static	struct x_defbindings const x_defbindings[] = {
	{ XFUNC_del_back,		0, CTRL('?') },
	{ XFUNC_del_bword,		1, CTRL('?') },
	{ XFUNC_eot_del,		0, CTRL('D') },
	{ XFUNC_del_back,		0, CTRL('H') },
	{ XFUNC_del_bword,		1, CTRL('H') },
	{ XFUNC_del_bword,		1,      'h'  },
	{ XFUNC_mv_bword,		1,      'b'  },
	{ XFUNC_mv_fword,		1,      'f'  },
	{ XFUNC_del_fword,		1,      'd'  },
	{ XFUNC_mv_back,		0, CTRL('B') },
	{ XFUNC_mv_forw,		0, CTRL('F') },
	{ XFUNC_search_char_forw,	0, CTRL(']') },
	{ XFUNC_search_char_back,	1, CTRL(']') },
	{ XFUNC_newline,		0, CTRL('M') },
	{ XFUNC_newline,		0, CTRL('J') },
	{ XFUNC_end_of_text,		0, CTRL('_') },
	{ XFUNC_abort,			0, CTRL('G') },
	{ XFUNC_prev_com,		0, CTRL('P') },
	{ XFUNC_next_com,		0, CTRL('N') },
	{ XFUNC_nl_next_com,		0, CTRL('O') },
	{ XFUNC_search_hist,		0, CTRL('R') },
	{ XFUNC_beg_hist,		1,      '<'  },
	{ XFUNC_end_hist,		1,      '>'  },
	{ XFUNC_goto_hist,		1,      'g'  },
	{ XFUNC_mv_end,			0, CTRL('E') },
	{ XFUNC_mv_begin,		0, CTRL('A') },
	{ XFUNC_draw_line,		0, CTRL('L') },
	{ XFUNC_meta1,			0, CTRL('[') },
	{ XFUNC_meta2,			0, CTRL('X') },
	{ XFUNC_kill,			0, CTRL('K') },
	{ XFUNC_yank,			0, CTRL('Y') },
	{ XFUNC_meta_yank,		1,      'y'  },
	{ XFUNC_literal,		0, CTRL('^') },
        { XFUNC_comment,		1,	'#'  },
#if defined(BRL) && defined(TIOCSTI)
	{ XFUNC_stuff,			0, CTRL('T') },
#else
	{ XFUNC_transpose,		0, CTRL('T') },
#endif
	{ XFUNC_complete,		1, CTRL('[') },
        { XFUNC_comp_list,		1,	'='  },
	{ XFUNC_enumerate,		1,	'?'  },
        { XFUNC_expand,			1,	'*'  },
	{ XFUNC_comp_file,		1, CTRL('X') },
	{ XFUNC_comp_comm,		2, CTRL('[') },
	{ XFUNC_list_comm,		2,	'?'  },
	{ XFUNC_list_file,		2, CTRL('Y') },
	{ XFUNC_set_mark,		1,	' '  },
	{ XFUNC_kill_region,		0, CTRL('W') },
	{ XFUNC_xchg_point_mark,	2, CTRL('X') },
	{ XFUNC_version,		0, CTRL('V') },
#ifdef DEBUG
        { XFUNC_debug_info,		1, CTRL('H') },
#endif
	{ XFUNC_prev_histword,		1,	'.'  },
	{ XFUNC_prev_histword,		1,	'_'  },
        { XFUNC_set_arg,		1,	'0'  },
        { XFUNC_set_arg,		1,	'1'  },
        { XFUNC_set_arg,		1,	'2'  },
        { XFUNC_set_arg,		1,	'3'  },
        { XFUNC_set_arg,		1,	'4'  },
        { XFUNC_set_arg,		1,	'5'  },
        { XFUNC_set_arg,		1,	'6'  },
        { XFUNC_set_arg,		1,	'7'  },
        { XFUNC_set_arg,		1,	'8'  },
        { XFUNC_set_arg,		1,	'9'  },
        { XFUNC_fold_upper,		1,	'U'  },
        { XFUNC_fold_upper,		1,	'u'  },
        { XFUNC_fold_lower,		1,	'L'  },
        { XFUNC_fold_lower,		1,	'l'  },
        { XFUNC_fold_capitialize,	1,	'C'  },
        { XFUNC_fold_capitialize,	1,	'c'  },
#ifdef OS2
	{ XFUNC_meta3,			0,	0xE0 },
	{ XFUNC_mv_back,		3,	'K'  },
	{ XFUNC_mv_forw,		3,	'M'  },
	{ XFUNC_next_com,		3,	'P'  },
	{ XFUNC_prev_com,		3,	'H'  },
#endif /* OS2 */
	/* These for ansi arrow keys: arguablely shouldn't be here by
	 * default, but its simpler/faster/smaller than using termcap
	 * entries.
	 */
        { XFUNC_meta2,			1,	'['  },
	{ XFUNC_prev_com,		2,	'A'  },
	{ XFUNC_next_com,		2,	'B'  },
	{ XFUNC_mv_forw,		2,	'C'  },
	{ XFUNC_mv_back,		2,	'D'  },
};

int
x_emacs(buf, len)
	char *buf;
	size_t len;
{
	int	c;
	const char *p;
	int	i;
	Findex	f;

	xbp = xbuf = buf; xend = buf + len;
	xlp = xcp = xep = buf;
	*xcp = 0;
	xlp_valid = TRUE;
	xmp = NULL;
	x_curprefix = 0;
	macroptr = (char *) 0;
	x_histp = histptr + 1;
	x_last_command = XFUNC_error;

	xx_cols = x_cols;
	x_col = promptlen(prompt, &p);
	prompt_skip = p - prompt;
	x_adj_ok = 1;
	x_displen = xx_cols - 2 - x_col;
	x_adj_done = 0;

	pprompt(prompt, 0);

	if (x_nextcmd >= 0) {
		int off = source->line - x_nextcmd;
		if (histptr - history >= off)
			x_load_hist(histptr - off);
		x_nextcmd = -1;
	}

	while (1) {
		x_flush();
		if ((c = x_e_getc()) < 0)
			return 0;

		f = x_curprefix == -1 ? XFUNC_insert
			: x_tab[x_curprefix][c&CHARMASK]; 

		if (!(x_ftab[f].xf_flags & XF_PREFIX)
		    && x_last_command != XFUNC_set_arg)
		{
			x_arg = 1;
			x_arg_defaulted = 1;
		}
		i = c | (x_curprefix << 8);
		x_curprefix = 0;
		switch (i = (*x_ftab[f].xf_func)(i))  {
		  case KSTD:
			if (!(x_ftab[f].xf_flags & XF_PREFIX))
				x_last_command = f;
			break;
		  case KEOL:
			i = xep - xbuf;
			return i;
		  case KINTR:	/* special case for interrupt */
			trapsig(SIGINT);
			x_mode(FALSE);
			unwind(LSHELL);
		}
	}
}

static int
x_insert(c)
	int c;
{
	char	str[2];

	/*
	 *  Should allow tab and control chars.
	 */
	if (c == 0)  {
		x_e_putc(BEL);
		return KSTD;
	}
	str[0] = c;
	str[1] = '\0';
	while (x_arg--)
		x_ins(str);
	return KSTD;
}

static int
x_ins_string(c)
	int c;
{
	if (macroptr)   {
		x_e_putc(BEL);
		return KSTD;
	}
	macroptr = x_atab[c>>8][c & CHARMASK];
	if (macroptr && !*macroptr) {
		/* XXX bell? */
		macroptr = (char *) 0;
	}
	return KSTD;
}

static int
x_do_ins(cp, len)
	const char *cp;
	int len;
{
	if (xep+len >= xend) {
		x_e_putc(BEL);
		return -1;
	}

	memmove(xcp+len, xcp, xep - xcp + 1);
	memmove(xcp, cp, len);
	xcp += len;
	xep += len;
	return 0;
}

static int
x_ins(s)
	char	*s;
{
	char *cp = xcp;
	register int	adj = x_adj_done;

	if (x_do_ins(s, strlen(s)) < 0)
		return -1;
	/*
	 * x_zots() may result in a call to x_adjust()
	 * we want xcp to reflect the new position.
	 */
	xlp_valid = FALSE;
	x_lastcp();
	x_adj_ok = (xcp >= xlp);
	x_zots(cp);
	if (adj == x_adj_done)	/* has x_adjust() been called? */
	{
	  /* no */
	  for (cp = xlp; cp > xcp; )
	    x_bs(*--cp);
	}

	x_adj_ok = 1;
	return 0;
}

static int
x_del_back(c)
	int c;
{
	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);
	x_delete(x_arg, FALSE);
	return KSTD;
}

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

	if (!nleft) {
		x_e_putc(BEL);
		return KSTD;
	}
	if (x_arg > nleft)
		x_arg = nleft;
	x_delete(x_arg, FALSE);
	return KSTD;
}

/* Delete nc chars to the right of the cursor (including cursor position) */
static void
x_delete(nc, force_push)
	int nc;
	int force_push;
{
	int	i,j;
	char	*cp;
	
	if (nc == 0)
		return;
	if (xmp != NULL && xmp > xcp) {
		if (xcp + nc > xmp)
			xmp = xcp;
		else
			xmp -= nc;
	}

	/*
	 * This lets us yank a word we have deleted.
	 */
	if (nc > 1 || force_push)
		x_push(nc);

	xep -= nc;
	cp = xcp;
	j = 0;
	i = nc;
	while (i--)  {
		j += x_size(*cp++);
	}
	memmove(xcp, xcp+nc, xep - xcp + 1);	/* Copies the null */
	x_adj_ok = 0;			/* don't redraw */
	x_zots(xcp);
	/*
	 * if we are already filling the line,
	 * there is no need to ' ','\b'.
	 * But if we must, make sure we do the minimum.
	 */
	if ((i = xx_cols - 2 - x_col) > 0)
	{
	  j = (j < i) ? j : i;
	  i = j;
	  while (i--)
	    x_e_putc(' ');
	  i = j;
	  while (i--)
	    x_e_putc('\b');
	}
	/*x_goto(xcp);*/
	x_adj_ok = 1;
	xlp_valid = FALSE;
	for (cp = x_lastcp(); cp > xcp; )
		x_bs(*--cp);

	return;	
}

static int
x_del_bword(c)
	int c;
{
	x_delete(x_bword(), FALSE);
	return KSTD;
}

static int
x_mv_bword(c)
	int c;
{
	(void)x_bword();
	return KSTD;
}

static int
x_mv_fword(c)
	int c;
{
	x_goto(xcp + x_fword());
	return KSTD;
}

static int
x_del_fword(c)
	int c;
{
	x_delete(x_fword(), FALSE);
	return KSTD;
}

static int
x_bword()
{
	int	nc = 0;
	register char *cp = xcp;

	if (cp == xbuf)  {
		x_e_putc(BEL);
		return 0;
	}
	while (x_arg--)
	{
	  while (cp != xbuf && is_mfs(cp[-1]))
	  {
	    cp--;
	    nc++;
	  }
	  while (cp != xbuf && !is_mfs(cp[-1]))
	  {
	    cp--;
	    nc++;
	  }
	}
	x_goto(cp);
	return nc;
}

static int
x_fword()
{
	int	nc = 0;
	register char	*cp = xcp;

	if (cp == xep)  {
		x_e_putc(BEL);
		return 0;
	}
	while (x_arg--)
	{
	  while (cp != xep && is_mfs(*cp))
	  {
	    cp++;
	    nc++;
	  }
	  while (cp != xep && !is_mfs(*cp))
	  {
	    cp++;
	    nc++;
	  }
	}
	return nc;
}

static void
x_goto(cp)
	register char *cp;
{
  if (cp < xbp || cp >= (xbp + x_displen))
  {
    /* we are heading off screen */
    xcp = cp;
    x_adjust();
  }
  else
  {
    if (cp < xcp)		/* move back */
    {
      while (cp < xcp)
	x_bs(*--xcp);
    }
    else
    {
      if (cp > xcp)		/* move forward */
      {
	while (cp > xcp)
	  x_zotc(*xcp++);
      }
    }
  }
}

static void
x_bs(c)
	int c;
{
	register int i;
	i = x_size(c);
	while (i--)
		x_e_putc('\b');
}

static int
x_size_str(cp)
	register char *cp;
{
	register int size = 0;
	while (*cp)
		size += x_size(*cp++);
	return size;
}

static int
x_size(c)
	int c;
{
	if (c=='\t')
		return 4;	/* Kludge, tabs are always four spaces. */
	if (iscntrl(c))		/* control char */
		return 2;
	return 1;
}

static void
x_zots(str)
	register char *str;
{
  register int	adj = x_adj_done;

  x_lastcp();
  while (*str && str < xlp && adj == x_adj_done)
    x_zotc(*str++);
}

static void
x_zotc(c)
	int c;
{
	if (c == '\t')  {
		/*  Kludge, tabs are always four spaces.  */
		x_e_puts("    ");
	} else if (iscntrl(c))  {
		x_e_putc('^');
		x_e_putc(UNCTRL(c));
	} else
		x_e_putc(c);
}

static int
x_mv_back(c)
	int c;
{