text: /* vi:set ts=8 sw=4:
   *
   * VIM - Vi IMproved	by Bram Moolenaar
   *
   * Do ":help uganda"  in Vim to read copying and usage conditions.
   * Do ":help credits" in Vim to see a list of people who contributed.
   * See README.txt for an overview of the Vim source code.
   */
  
  /*
   * Tcl extensions by Ingo Wilken <Ingo.Wilken@informatik.uni-oldenburg.de>
   * Last modification: Wed May 10 21:28:44 CEST 2000
   * Requires Tcl 8.0 or higher.
   *
   *  Variables:
   *  ::vim::current(buffer)	# Name of buffer command for current buffer.
   *  ::vim::current(window)	# Name of window command for current window.
   *  ::vim::range(start)		# Start of current range (line number).
   *  ::vim::range(end)		# End of current range (line number).
   *  ::vim::lbase		# Start of line/column numbers (1 or 0).
   *
   *  Commands:
   *  ::vim::command {cmd}	# Execute ex command {cmd}.
   *  ::vim::option {opt} [val]	# Get/Set option {opt}.
   *  ::vim::expr {expr}		# Evaluate {expr} using vim's evaluator.
   *  ::vim::beep			# Guess.
   *
   *  set buf [::vim::buffer {n}]	# Create Tcl command for buffer N.
   *  set bl [::vim::buffer list] # Get list of Tcl commands of all buffers.
   *  ::vim::buffer exists {n}	# True if buffer {n} exists.
   *
   *  set wl [::vim::window list] # Get list of Tcl commands of all windows.
   *
   *  set n [$win height]		# Report window height.
   *  $win height {n}		# Set window height to {n}.
   *  array set pos [$win cursor] # Get cursor position.
   *  $win cursor {row} {col}	# Set cursor position.
   *  $win cursor pos		# Set cursor position from array var "pos"
   *  $win delcmd {cmd}		# Register callback command for closed window.
   *  $win option {opt} [val]	# Get/Set vim option in context of $win.
   *  $win command {cmd}		# Execute ex command in context of $win.
   *  $win expr {expr}		# Evaluate vim expression in context of $win.
   *  set buf [$win buffer]	# Create Tcl command for window's buffer.
   *
   *  $buf name			# Reports file name in buffer.
   *  $buf number			# Reports buffer number.
   *  set l [$buf get {n}]	# Get buffer line {n} as a string.
   *  set L [$buf get {n} {m}]	# Get lines {n} through {m} as a list.
   *  $buf count			# Reports number of lines in buffer.
   *  $buf last			# Reports number of last line in buffer.
   *  $buf delete {n}		# Delete line {n}.
   *  $buf delete {n} {m}		# Delete lines {n} through {m}.
   *  $buf set {n} {l}		# Set line {n} to string {l}.
   *  $buf set {n} {m} {L}	# Set lines {n} through {m} from list {L}.
   *				# Delete/inserts lines as appropriate.
   *  $buf option {opt} [val]	# Get/Set vim option in context of $buf.
   *  $buf command {cmd}		# Execute ex command in context of $buf
   *  $buf expr {cmd}		# Evaluate vim expression in context of $buf.
   *  array set pos [$buf mark {m}]   # Get position of mark.
   *  $buf append {n} {str}	# Append string {str} to buffer,after line {n}.
   *  $buf insert {n} {str}	# Insert string {str} in buffer as line {n}.
   *  $buf delcmd {cmd}		# Register callback command for deleted buffer.
   *  set wl [$buf windows]	# Get list of Tcl commands for all windows of
   *				# this buffer.
  TODO:
   *  ::vim::buffer new		#   create new buffer + Tcl command
   */
  
  #include "vim.h"
  #undef EXTERN			/* tcl.h defines it too */
  
  #ifdef DYNAMIC_TCL
  # define USE_TCL_STUBS /* use tcl's stubs mechanism */
  #endif
  
  #include <tcl.h>
  #include <string.h>
  
  typedef struct
  {
      Tcl_Interp *interp;
      int exitvalue;
      int range_start, range_end;
      int lbase;
      char *curbuf, *curwin;
  } tcl_info;
  
  static tcl_info tclinfo = { NULL, 0, 0, 0, 0, NULL, NULL };
  
  #define VAR_RANGE1	"::vim::range(start)"
  #define VAR_RANGE2	"::vim::range(begin)"
  #define VAR_RANGE3	"::vim::range(end)"
  #define VAR_CURBUF	"::vim::current(buffer)"
  #define VAR_CURWIN	"::vim::current(window)"
  #define VAR_LBASE	"::vim::lbase"
  #define VAR_CURLINE	"line"
  #define VAR_CURLNUM	"lnum"
  #define VARNAME_SIZE	64
  
  #define row2tcl(x)  ((x) - (tclinfo.lbase==0))
  #define row2vim(x)  ((x) + (tclinfo.lbase==0))
  #define col2tcl(x)  ((x) + (tclinfo.lbase!=0))
  #define col2vim(x)  ((x) - (tclinfo.lbase!=0))
  
  
  #define VIMOUT	((ClientData)1)
  #define VIMERR	((ClientData)2)
  
  /* This appears to be new in Tcl 8.4. */
  #ifndef CONST84
  # define CONST84
  #endif
  
  /*
   *  List of Tcl interpreters who reference a vim window or buffer.
   *  Each buffer and window has it's own list in the w_tcl_ref or b_tcl_ref
   *  struct member.  We need this because Tcl can create sub-interpreters with
   *  the "interp" command, and each interpreter can reference all windows and
   *  buffers.
   */
  struct ref
  {
      struct ref	*next;
  
      Tcl_Interp	*interp;
      Tcl_Command cmd;	    /* Tcl command that represents this object */
      Tcl_Obj	*delcmd;    /* Tcl command to call when object is being del. */
      void	*vimobj;    /* Vim window or buffer (win_T* or buf_T*) */
  };
  static char * tclgetbuffer _ANSI_ARGS_((Tcl_Interp *interp, buf_T *buf));
  static char * tclgetwindow _ANSI_ARGS_((Tcl_Interp *interp, win_T *win));
  static int tclsetdelcmd _ANSI_ARGS_((Tcl_Interp *interp, struct ref *reflist, void *vimobj, Tcl_Obj *delcmd));
  static int tclgetlinenum _ANSI_ARGS_ ((Tcl_Interp *interp, Tcl_Obj *obj, int *valueP, buf_T *buf));
  static win_T *tclfindwin _ANSI_ARGS_ ((buf_T *buf));
  static int tcldoexcommand _ANSI_ARGS_ ((Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[], int objn));
  static int tclsetoption _ANSI_ARGS_ ((Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[], int objn));
  static int tclvimexpr _ANSI_ARGS_ ((Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[], int objn));
  static void tcldelthisinterp _ANSI_ARGS_ ((void));
  
  static int vimerror _ANSI_ARGS_((Tcl_Interp *interp));
  static void tclmsg _ANSI_ARGS_((char *text));
  static void tclerrmsg _ANSI_ARGS_((char *text));
  static void tclupdatevars _ANSI_ARGS_((void));
  
  static struct ref refsdeleted;	/* dummy object for deleted ref list */
  
  /*****************************************************************************
   * TCL interface manager
   ****************************************************************************/
  
  #if defined(DYNAMIC_TCL) || defined(PROTO)
  # ifndef DYNAMIC_TCL_DLL
  #  define DYNAMIC_TCL_DLL "tcl83.dll"
  # endif
  # ifndef DYNAMIC_TCL_VER
  #  define DYNAMIC_TCL_VER "8.3"
  # endif
  
  # ifndef  DYNAMIC_TCL /* Just generating prototypes */
  typedef int HANDLE;
  # endif
  
  /*
   * Declare HANDLE for tcl.dll and function pointers.
   */
  static HANDLE hTclLib = NULL;
  Tcl_Interp* (*dll_Tcl_CreateInterp)();
  void (*dll_Tcl_FindExecutable)(const void *);
  
  /*
   * Table of name to function pointer of tcl.
   */
  #define TCL_PROC FARPROC
  static struct {
      char* name;
      TCL_PROC* ptr;
  } tcl_funcname_table[] = {
      {"Tcl_CreateInterp", (TCL_PROC*)&dll_Tcl_CreateInterp},
      {"Tcl_FindExecutable", (TCL_PROC*)&dll_Tcl_FindExecutable},
      {NULL, NULL},
  };
  
  /*
   * Make all runtime-links of tcl.
   *
   * 1. Get module handle using LoadLibraryEx.
   * 2. Get pointer to tcl function by GetProcAddress.
   * 3. Repeat 2, until get all functions will be used.
   *
   * Parameter 'libname' provides name of DLL.
   * Return OK or FAIL.
   */
      static int
  tcl_runtime_link_init(char *libname, int verbose)
  {
      int i;
  
      if (hTclLib)
  	return OK;
      if (!(hTclLib = vimLoadLib(libname)))
      {
  	if (verbose)
  	    EMSG2(_(e_loadlib), libname);
  	return FAIL;
      }
      for (i = 0; tcl_funcname_table[i].ptr; ++i)
      {
  	if (!(*tcl_funcname_table[i].ptr = GetProcAddress(hTclLib,
  			tcl_funcname_table[i].name)))
  	{
  	    FreeLibrary(hTclLib);
  	    hTclLib = NULL;
  	    if (verbose)
  		EMSG2(_(e_loadfunc), tcl_funcname_table[i].name);
  	    return FAIL;
  	}
      }
      return OK;
  }
  #endif /* defined(DYNAMIC_TCL) || defined(PROTO) */
  
  #ifdef DYNAMIC_TCL
  static char *find_executable_arg = NULL;
  #endif
  
      void
  vim_tcl_init(arg)
      char	*arg;
  {
  #ifndef DYNAMIC_TCL
      Tcl_FindExecutable(arg);
  #else
      find_executable_arg = arg;
  #endif
  }
  
  #if defined(DYNAMIC_TCL) || defined(PROTO)
  
  static int stubs_initialized = FALSE;
  
  /*
   * Return TRUE if the TCL interface can be used.
   */
      int
  tcl_enabled(verbose)
      int		verbose;
  {
      if (!stubs_initialized && find_executable_arg != NULL
  	    && tcl_runtime_link_init(DYNAMIC_TCL_DLL, verbose) == OK)
      {
  	Tcl_Interp *interp;
  
  	dll_Tcl_FindExecutable(find_executable_arg);
  
  	if (interp = dll_Tcl_CreateInterp())
  	{
  	    if (Tcl_InitStubs(interp, DYNAMIC_TCL_VER, 0))
  	    {
  		Tcl_DeleteInterp(interp);
  		stubs_initialized = TRUE;
  	    }
  	    /* FIXME: When Tcl_InitStubs() was failed, how delete interp? */
  	}
      }
      return stubs_initialized;
  }
  #endif
  
      void
  tcl_end()
  {
  #ifdef DYNAMIC_TCL
      if (hTclLib)
      {
  	FreeLibrary(hTclLib);
  	hTclLib = NULL;
      }
  #endif
  }
  
  /****************************************************************************
    Tcl commands
   ****************************************************************************/
  
  /*
   * Replace standard "exit" command.
   *
   * Delete the Tcl interpreter; a new one will be created with the next
   * :tcl command). The exit code is saved (and retrieved in tclexit()).
   * Since Tcl's exit is never expected to return and this replacement
   * does, then (except for a trivial case) additional Tcl commands will
   * be run. Since the interpreter is now marked as deleted, an error
   * will be returned -- typically "attempt to call eval in deleted
   * interpreter". Hopefully, at this point, checks for TCL_ERROR take
   * place and control percolates back up to Vim -- but with this new error
   * string in the interpreter's result value. Therefore it would be
   * useless for this routine to return the exit code via Tcl_SetResult().
   */
      static int
  exitcmd(dummy, interp, objc, objv)
      ClientData dummy UNUSED;
      Tcl_Interp *interp;
      int objc;
      Tcl_Obj *CONST objv[];
  {
      int value = 0;
  
      switch (objc)
      {
  	case 2:
  	    if (Tcl_GetIntFromObj(interp, objv[1], &value) != TCL_OK)
  		break;
  	    /* FALLTHROUGH */
  	case 1:
  	    tclinfo.exitvalue = value;
  
  	    Tcl_DeleteInterp(interp);
  	    break;
  	default:
  	    Tcl_WrongNumArgs(interp, 1, objv, "?returnCode?");
      }
      return TCL_ERROR;
  }
  
  /*
   *  "::vim::beep" - what Vi[m] does best :-)
   */
      static int
  beepcmd(dummy, interp, objc, objv)
      ClientData dummy UNUSED;
      Tcl_Interp *interp;
      int objc;
      Tcl_Obj *CONST objv[];
  {
      if (objc != 1)
      {
  	Tcl_WrongNumArgs(interp, 1, objv, NULL);
  	return TCL_ERROR;
      }
      vim_beep();
      return TCL_OK;
  }
  
  /*
   *  "::vim::buffer list" - create a list of buffer commands.
   *  "::vim::buffer {N}" - create buffer command for buffer N.
   *  "::vim::buffer exists {N}" - test if buffer N exists.
   *  "::vim::buffer new" - create a new buffer (not implemented)
   */
      static int
  buffercmd(dummy, interp, objc, objv)
      ClientData dummy UNUSED;
      Tcl_Interp *interp;
      int objc;
      Tcl_Obj *CONST objv[];
  {
      char	*name;
      buf_T	*buf;
      Tcl_Obj	*resobj;
      int		err, n, idx;
      enum {BCMD_EXISTS, BCMD_LIST};
      static CONST84 char *bcmdoptions[] =
      {
  	"exists", "list", (char *)0
      };
  
      if (objc < 2)
      {
  	Tcl_WrongNumArgs(interp, 1, objv, "option");
  	return TCL_ERROR;
      }
      err = Tcl_GetIntFromObj(interp, objv[1], &n);
      if (err == TCL_OK)
      {
  	if (objc != 2)
  	{
  	    Tcl_WrongNumArgs(interp, 1, objv, "bufNumber");
  	    return TCL_ERROR;
  	}
  	for (buf = firstbuf; buf != NULL; buf = buf->b_next)
  	{
  	    if (buf->b_fnum == n)
  	    {
  		name = tclgetbuffer(interp, buf);
  		if (name == NULL)
  		    return TCL_ERROR;
  		Tcl_SetResult(interp, name, TCL_VOLATILE);
  		return TCL_OK;
  	    }
  	}
  	Tcl_SetResult(interp, _("invalid buffer number"), TCL_STATIC);
  	return TCL_ERROR;
      }
      Tcl_ResetResult(interp); /* clear error from Tcl_GetIntFromObj */
  
      err = Tcl_GetIndexFromObj(interp, objv[1], bcmdoptions, "option", 0, &idx);
      if (err != TCL_OK)
  	return err;
      switch (idx)
      {
  	case BCMD_LIST:
  	    if (objc != 2)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "");
  		err = TCL_ERROR;
  		break;
  	    }
  	    for (buf = firstbuf; buf != NULL; buf = buf->b_next)
  	    {
  		name = tclgetbuffer(interp, buf);
  		if (name == NULL)
  		{
  		    err = TCL_ERROR;
  		    break;
  		}
  		Tcl_AppendElement(interp, name);
  	    }
  	    break;
  
  	case BCMD_EXISTS:
  	    if (objc != 3)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "bufNumber");
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = Tcl_GetIntFromObj(interp, objv[2], &n);
  	    if (err == TCL_OK)
  	    {
  		buf = buflist_findnr(n);
  		resobj = Tcl_NewIntObj(buf != NULL);
  		Tcl_SetObjResult(interp, resobj);
  	    }
  	    break;
  
  	default:
  	    Tcl_SetResult(interp, _("not implemented yet"), TCL_STATIC);
  	    err = TCL_ERROR;
      }
      return err;
  }
  
  /*
   * "::vim::window list" - create list of window commands.
   */
      static int
  windowcmd(dummy, interp, objc, objv)
      ClientData	dummy UNUSED;
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
  {
      char	*what, *string;
      win_T	*win;
  
      if (objc != 2)
      {
  	Tcl_WrongNumArgs(interp, 1, objv, "option");
  	return TCL_ERROR;
      }
      what = Tcl_GetStringFromObj(objv[1], NULL);
      if (strcmp(what, "list") == 0)
      {
  	FOR_ALL_WINDOWS(win)
  	{
  	    string = tclgetwindow(interp, win);
  	    if (string == NULL)
  		return TCL_ERROR;
  	    Tcl_AppendElement(interp, string);
  	}
  	return TCL_OK;
      }
      Tcl_SetResult(interp, _("unknown option"), TCL_STATIC);
      return TCL_ERROR;
  }
  
  /*
   * flags for bufselfcmd and winselfcmd to indicate outstanding actions.
   */
  #define FL_UPDATE_SCREEN	(1<<0)
  #define FL_UPDATE_CURBUF	(1<<1)
  #define FL_ADJUST_CURSOR	(1<<2)
  
  /*
   * This function implements the buffer commands.
   */
      static int
  bufselfcmd(ref, interp, objc, objv)
      ClientData	ref;
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
  {
      int		opt, err, idx, flags;
      int		val1, val2, n, i;
      buf_T	*buf, *savebuf;
      win_T	*win, *savewin;
      Tcl_Obj	*resobj;
      pos_T	*pos;
      char	*line;
  
      enum
      {
  	BUF_APPEND, BUF_COMMAND, BUF_COUNT, BUF_DELCMD, BUF_DELETE, BUF_EXPR,
  	BUF_GET, BUF_INSERT, BUF_LAST, BUF_MARK, BUF_NAME, BUF_NUMBER,
  	BUF_OPTION, BUF_SET, BUF_WINDOWS
      };
      static CONST84 char *bufoptions[] =
      {
  	"append", "command", "count", "delcmd", "delete", "expr",
  	"get", "insert", "last", "mark", "name", "number",
  	"option", "set", "windows", (char *)0
      };
  
      if (objc < 2)
      {
  	Tcl_WrongNumArgs(interp, 1, objv, "option ?arg ...?");
  	return TCL_ERROR;
      }
  
      err = Tcl_GetIndexFromObj(interp, objv[1], bufoptions, "option", 0, &idx);
      if (err != TCL_OK)
  	return err;
  
      buf = (buf_T *)((struct ref *)ref)->vimobj;
      savebuf = curbuf;  curbuf = buf;
      savewin = curwin;  curwin = tclfindwin(buf);
      flags = 0;
      opt = 0;
  
      switch (idx)
      {
  	case BUF_COMMAND:
  	    err = tcldoexcommand(interp, objc, objv, 2);
  	    flags |= FL_UPDATE_SCREEN;
  	    break;
  
  	case BUF_OPTION:
  	    err = tclsetoption(interp, objc, objv, 2);
  	    flags |= FL_UPDATE_SCREEN;
  	    break;
  
  	case BUF_EXPR:
  	    err = tclvimexpr(interp, objc, objv, 2);
  	    break;
  
  	case BUF_NAME:
  	    /*
  	     *	Get filename of buffer.
  	     */
  	    if (objc != 2)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, NULL);
  		err = TCL_ERROR;
  		break;
  	    }
  	    if (buf->b_ffname)
  		Tcl_SetResult(interp, (char *)buf->b_ffname, TCL_VOLATILE);
  	    else
  		Tcl_SetResult(interp, "", TCL_STATIC);
  	    break;
  
  	case BUF_LAST:
  	    /*
  	     * Get line number of last line.
  	     */
  	    opt = 1;
  	    /* fallthrough */
  	case BUF_COUNT:
  	    /*
  	     * Get number of lines in buffer.
  	     */
  	    if (objc != 2)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, NULL);
  		err = TCL_ERROR;
  		break;
  	    }
  	    val1 = (int)buf->b_ml.ml_line_count;
  	    if (opt)
  		val1 = row2tcl(val1);
  
  	    resobj = Tcl_NewIntObj(val1);
  	    Tcl_SetObjResult(interp, resobj);
  	    break;
  
  	case BUF_NUMBER:
  	    /*
  	     * Get buffer's number.
  	     */
  	    if (objc != 2)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, NULL);
  		err = TCL_ERROR;
  		break;
  	    }
  	    resobj = Tcl_NewIntObj((int)buf->b_fnum);
  	    Tcl_SetObjResult(interp, resobj);
  	    break;
  
  	case BUF_GET:
  	    if (objc != 3 && objc != 4)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "lineNumber ?lineNumber?");
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = tclgetlinenum(interp, objv[2], &val1, buf);
  	    if (err != TCL_OK)
  		break;
  	    if (objc == 4)
  	    {
  		err = tclgetlinenum(interp, objv[3], &val2, buf);
  		if (err != TCL_OK)
  		    break;
  		if (val1 > val2)
  		{
  		    n = val1; val1 = val2; val2 = n;
  		}
  		Tcl_ResetResult(interp);
  
  		for (n = val1; n <= val2 && err == TCL_OK; n++)
  		{
  		    line = (char *)ml_get_buf(buf, (linenr_T)n, FALSE);
  		    if (line)
  			Tcl_AppendElement(interp, line);
  		    else
  			err = TCL_ERROR;
  		}
  	    }
  	    else {  /* objc == 3 */
  		line = (char *)ml_get_buf(buf, (linenr_T)val1, FALSE);
  		Tcl_SetResult(interp, line, TCL_VOLATILE);
  	    }
  	    break;
  
  	case BUF_SET:
  	    if (objc != 4 && objc != 5)
  	    {
  		Tcl_WrongNumArgs(interp, 3, objv, "lineNumber ?lineNumber? stringOrList");
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = tclgetlinenum(interp, objv[2], &val1, buf);
  	    if (err != TCL_OK)
  		return TCL_ERROR;
  	    if (objc == 4)
  	    {
  		/*
  		 *  Replace one line with a string.
  		 *	$buf set {n} {string}
  		 */
  		line = Tcl_GetStringFromObj(objv[3], NULL);
  		if (u_savesub((linenr_T)val1) != OK)
  		{
  		    Tcl_SetResult(interp, _("cannot save undo information"), TCL_STATIC);
  		    err = TCL_ERROR;
  		}
  		else
  		if (ml_replace((linenr_T)val1, (char_u *)line, TRUE) != OK)
  		{
  		    Tcl_SetResult(interp, _("cannot replace line"), TCL_STATIC);
  		    err = TCL_ERROR;
  		}
  		else
  		{
  		    changed_bytes((linenr_T)val1, 0);
  		    flags |= FL_UPDATE_CURBUF;
  		}
  		break;
  	    }
  	    else
  	    {
  		/*
  		 * Replace several lines with the elements of a Tcl list.
  		 *	$buf set {n} {m} {list}
  		 * If the list contains more than {m}-{n}+1 elements, they
  		 * are * inserted after line {m}.  If the list contains fewer
  		 * elements, * the lines from {n}+length({list}) through {m}
  		 * are deleted.
  		 */
  		int	    lc;
  		Tcl_Obj	    **lv;
  
  		err = tclgetlinenum(interp, objv[3], &val2, buf);
  		if (err != TCL_OK)
  		    break;
  		err = Tcl_ListObjGetElements(interp, objv[4], &lc, &lv);
  		if (err != TCL_OK)
  		    break;
  		if (val1 > val2)
  		{
  		    n = val1;
  		    val1 = val2;
  		    val2 = n;
  		}
  
  		n = val1;
  		if (u_save((linenr_T)(val1 - 1), (linenr_T)(val2 + 1)) != OK)
  		{
  		    Tcl_SetResult(interp, _("cannot save undo information"),
  								  TCL_STATIC);
  		    err = TCL_ERROR;
  		    break;
  		}
  		flags |= FL_UPDATE_CURBUF;
  
  		for (i = 0; i < lc && n <= val2; i++)
  		{
  		    line = Tcl_GetStringFromObj(lv[i], NULL);
  		    if (ml_replace((linenr_T)n, (char_u *)line, TRUE) != OK)
  			goto setListError;
  		    ++n;
  		}
  		if (i < lc)
  		{
  		    /* append lines */
  		    do
  		    {
  			line = Tcl_GetStringFromObj(lv[i], NULL);
  			if (ml_append((linenr_T)(n - 1),
  					      (char_u *)line, 0, FALSE) != OK)
  			    goto setListError;
  			++n;
  			++i;
  		    } while (i < lc);
  		}
  		else if (n <= val2)
  		{
  		    /* did not replace all lines, delete */
  		    i = n;
  		    do
  		    {
  			if (ml_delete((linenr_T)i, FALSE) != OK)
  			    goto setListError;
  			++n;
  		    } while (n <= val2);
  		}
  		lc -= val2 - val1 + 1;	/* number of lines to be replaced */
  		mark_adjust((linenr_T)val1, (linenr_T)val2, (long)MAXLNUM,
  								    (long)lc);
  		changed_lines((linenr_T)val1, 0, (linenr_T)val2 + 1, (long)lc);
  		break;
      setListError:
  		u_undo(1);  /* ??? */
  		Tcl_SetResult(interp, _("cannot set line(s)"), TCL_STATIC);
  		err = TCL_ERROR;
  	    }
  	    break;
  
  	case BUF_DELETE:
  	    if (objc != 3  &&  objc != 4)
  	    {
  		Tcl_WrongNumArgs(interp, 3, objv, "lineNumber ?lineNumber?");
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = tclgetlinenum(interp, objv[2], &val1, buf);
  	    if (err != TCL_OK)
  		break;
  	    val2 = val1;
  	    if (objc == 4)
  	    {
  		err = tclgetlinenum(interp, objv[3], &val2, buf);
  		if (err != TCL_OK)
  		    return err;
  		if (val1 > val2)
  		{
  		    i = val1; val1 = val2; val2 = i;
  		}
  	    }
  	    n = val2 - val1 + 1;
  	    if (u_savedel((linenr_T)val1, (long)n) != OK)
  	    {
  		Tcl_SetResult(interp, _("cannot save undo information"),
  								  TCL_STATIC);
  		err = TCL_ERROR;
  		break;
  	    }
  	    for (i = 0; i < n; i++)
  	    {
  		ml_delete((linenr_T)val1, FALSE);
  		err = vimerror(interp);
  		if (err != TCL_OK)
  		    break;
  	    }
  	    if (i > 0)
  		deleted_lines_mark((linenr_T)val1, (long)i);
  	    flags |= FL_ADJUST_CURSOR|FL_UPDATE_SCREEN;
  	    break;
  
  	case BUF_MARK:
  	    if (objc != 3)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "markName");
  		err = TCL_ERROR;
  		break;
  	    }
  	    line = Tcl_GetStringFromObj(objv[2], NULL);
  
  	    pos = NULL;
  	    if (line[0] != '\0'  &&  line[1] == '\0')
  	    {
  		pos = getmark(line[0], FALSE);
  	    }
  	    if (pos == NULL)
  	    {
  		Tcl_SetResult(interp, _("invalid mark name"), TCL_STATIC);
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = vimerror(interp);
  	    if (err != TCL_OK)
  		break;
  	    if (pos->lnum <= 0)
  	    {
  		Tcl_SetResult(interp, _("mark not set"), TCL_STATIC);
  		err = TCL_ERROR;
  	    }
  	    else
  	    {
  		char rbuf[64];
  
  		sprintf(rbuf, _("row %d column %d"),
  			     (int)row2tcl(pos->lnum), (int)col2tcl(pos->col));
  		Tcl_SetResult(interp, rbuf, TCL_VOLATILE);
  	    }
  	    break;
  
  	case BUF_INSERT:
  	    opt = 1;
  	    /* fallthrough */
  	case BUF_APPEND:
  	    if (objc != 4)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "lineNum text");
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = tclgetlinenum(interp, objv[2], &val1, buf);
  	    if (err != TCL_OK)
  		break;
  	    if (opt)
  		--val1;
  	    if (u_save((linenr_T)val1, (linenr_T)(val1+1)) != OK)
  	    {
  		Tcl_SetResult(interp, _("cannot save undo information"),
  								  TCL_STATIC);
  		err = TCL_ERROR;
  		break;
  	    }
  
  	    line = Tcl_GetStringFromObj(objv[3], NULL);
  	    if (ml_append((linenr_T)val1, (char_u *)line, 0, FALSE) != OK)
  	    {
  		Tcl_SetResult(interp, _("cannot insert/append line"),
  								  TCL_STATIC);
  		err = TCL_ERROR;
  		break;
  	    }
  	    appended_lines_mark((linenr_T)val1, 1L);
  	    flags |= FL_UPDATE_SCREEN;
  	    break;
  
  	case BUF_WINDOWS:
  	    /*
  	     * Return list of window commands.
  	     */
  	    if (objc != 2)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, NULL);
  		err = TCL_ERROR;
  		break;
  	    }
  	    Tcl_ResetResult(interp);
  	    FOR_ALL_WINDOWS(win)
  	    {
  		if (win->w_buffer == buf)
  		{
  		    line = tclgetwindow(interp, win);
  		    if (line != NULL)
  			Tcl_AppendElement(interp, line);
  		    else
  		    {
  			err = TCL_ERROR;
  			break;
  		    }
  		}
  	    }
  	    break;
  
  	case BUF_DELCMD:
  	    /*
  	     * Register deletion callback.
  	     * TODO: Should be able to register multiple callbacks
  	     */
  	    if (objc != 3)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "command");
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = tclsetdelcmd(interp, buf->b_tcl_ref, (void *)buf, objv[2]);
  	    break;
  
  	default:
  	    Tcl_SetResult(interp, _("not implemented yet"), TCL_STATIC);
  	    err = TCL_ERROR;
      }
  
      if (flags & FL_UPDATE_CURBUF)
  	redraw_curbuf_later(NOT_VALID);
      curbuf = savebuf;
      curwin = savewin;
      if (flags & FL_ADJUST_CURSOR)
  	check_cursor();
      if (flags & (FL_UPDATE_SCREEN | FL_UPDATE_CURBUF))
  	update_screen(NOT_VALID);
  
      return err;
  }
  
  /*
   * This function implements the window commands.
   */
      static int
  winselfcmd(ref, interp, objc, objv)
      ClientData	ref;
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
  {
      int		err, idx, flags;
      int		val1, val2;
      Tcl_Obj	*resobj;
      win_T	*savewin, *win;
      buf_T	*savebuf;
      char	*str;
  
      enum
      {
  	WIN_BUFFER, WIN_COMMAND, WIN_CURSOR, WIN_DELCMD, WIN_EXPR,
  	WIN_HEIGHT, WIN_OPTION
      };
      static CONST84 char *winoptions[] =
      {
  	"buffer", "command", "cursor", "delcmd", "expr",
  	"height", "option", (char *)0
      };
  
      if (objc < 2)
      {
  	Tcl_WrongNumArgs(interp, 1, objv, "option ?arg ...?");
  	return TCL_ERROR;
      }
  
      err = Tcl_GetIndexFromObj(interp, objv[1], winoptions, "option", 0,  &idx);
      if (err != TCL_OK)
  	return TCL_ERROR;
  
      win = (win_T *)((struct ref *)ref)->vimobj;
      savewin = curwin;  curwin = win;
      savebuf = curbuf;  curbuf = win->w_buffer;
      flags = 0;
  
      switch (idx)
      {
  	case WIN_OPTION:
  	    err = tclsetoption(interp, objc, objv, 2);
  	    flags |= FL_UPDATE_SCREEN;
  	    break;
  
  	case WIN_COMMAND:
  	    err = tcldoexcommand(interp, objc, objv, 2);
  	    flags |= FL_UPDATE_SCREEN;
  	    break;
  
  	case WIN_EXPR:
  	    err = tclvimexpr(interp, objc, objv, 2);
  	    break;
  
  	case WIN_HEIGHT:
  	    if (objc == 3)
  	    {
  		err = Tcl_GetIntFromObj(interp, objv[2], &val1);
  		if (err != TCL_OK)
  		    break;
  #ifdef FEAT_GUI
  		need_mouse_correct = TRUE;
  #endif
  		win_setheight(val1);
  		err = vimerror(interp);
  		if (err != TCL_OK)
  		    break;
  	    }
  	    else
  	    if (objc != 2)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "?value?");
  		err = TCL_ERROR;
  		break;
  	    }
  
  	    resobj = Tcl_NewIntObj((int)(win->w_height));
  	    Tcl_SetObjResult(interp, resobj);
  	    break;
  
  	case WIN_BUFFER:
  	    if (objc != 2)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, NULL);
  		err = TCL_ERROR;
  		break;
  	    }
  	    str = tclgetbuffer(interp, win->w_buffer);
  	    if (str)
  		Tcl_SetResult(interp, str, TCL_VOLATILE);
  	    else
  		err = TCL_ERROR;
  	    break;
  
  	case WIN_DELCMD:
  	    if (objc != 3)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "command");
  		err = TCL_ERROR;
  		break;
  	    }
  	    err = tclsetdelcmd(interp, win->w_tcl_ref, (void *)win, objv[2]);
  	    break;
  
  	case WIN_CURSOR:
  	    if (objc > 4)
  	    {
  		Tcl_WrongNumArgs(interp, 2, objv, "?arg1 ?arg2??");
  		err = TCL_ERROR;
  		break;
  	    }
  	    if (objc == 2)
  	    {
  		char buf[64];
  
  		sprintf(buf, _("row %d column %d"), (int)row2tcl(win->w_cursor.lnum), (int)col2tcl(win->w_cursor.col));
  		Tcl_SetResult(interp, buf, TCL_VOLATILE);
  		break;
  	    }
  	    else if (objc == 3)
  	    {
  		Tcl_Obj *part, *var;
  
  		part = Tcl_NewStringObj("row", -1);
  		var = Tcl_ObjGetVar2(interp, objv[2], part, TCL_LEAVE_ERR_MSG);
  		if (var == NULL)
  		{
  		    err = TCL_ERROR;
  		    break;
  		}
  		err = tclgetlinenum(interp, var, &val1, win->w_buffer);
  		if (err != TCL_OK)
  		    break;
  		part = Tcl_NewStringObj("column", -1);
  		var = Tcl_ObjGetVar2(interp, objv[2], part, TCL_LEAVE_ERR_MSG);
  		if (var == NULL)
  		{
  		    err = TCL_ERROR;
  		    break;
  		}
  		err = Tcl_GetIntFromObj(interp, var, &val2);
  		if (err != TCL_OK)
  		    break;
  	    }
  	    else {  /* objc == 4 */
  		err = tclgetlinenum(interp, objv[2], &val1, win->w_buffer);
  		if (err != TCL_OK)
  		    break;
  		err = Tcl_GetIntFromObj(interp, objv[3], &val2);
  		if (err != TCL_OK)
  		    break;
  	    }
  	    /* TODO: should check column */
  	    win->w_cursor.lnum = val1;
  	    win->w_cursor.col = col2vim(val2);
  	    flags |= FL_UPDATE_SCREEN;
  	    break;
  
  	default:
  	    Tcl_SetResult(interp, _("not implemented yet"), TCL_STATIC);
  	    break;
      }
  
      curwin = savewin;
      curbuf = savebuf;
      if (flags & FL_UPDATE_SCREEN)
  	update_screen(NOT_VALID);
  
      return err;
  }
  
  
      static int
  commandcmd(dummy, interp, objc, objv)
      ClientData	dummy UNUSED;
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
  {
      int		err;
  
      err = tcldoexcommand(interp, objc, objv, 1);
      update_screen(VALID);
      return err;
  }
  
      static int
  optioncmd(dummy, interp, objc, objv)
      ClientData	dummy UNUSED;
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
  {
      int		err;
  
      err = tclsetoption(interp, objc, objv, 1);
      update_screen(VALID);
      return err;
  }
  
      static int
  exprcmd(dummy, interp, objc, objv)
      ClientData	dummy UNUSED;
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
  {
      return tclvimexpr(interp, objc, objv, 1);
  }
  
  /****************************************************************************
    Support functions for Tcl commands
   ****************************************************************************/
  
  /*
   * Get a line number from 'obj' and convert it to vim's range.
   */
      static int
  tclgetlinenum(interp, obj, valueP, buf)
      Tcl_Interp	*interp;
      Tcl_Obj	*obj;
      int		*valueP;
      buf_T	*buf;
  {
      int err, i;
  
      enum { LN_BEGIN, LN_BOTTOM, LN_END, LN_FIRST, LN_LAST, LN_START, LN_TOP };
  
      static CONST84 char *keyw[] =
      {
  	"begin", "bottom", "end", "first", "last", "start", "top", (char *)0
      };
  
      err = Tcl_GetIndexFromObj(interp, obj, keyw, "", 0, &i);
      if (err == TCL_OK)
      {
  	switch (i)
  	{
  	    case LN_BEGIN:
  	    case LN_FIRST:
  	    case LN_START:
  	    case LN_TOP:
  		*valueP = 1;
  		break;
  	    case LN_BOTTOM:
  	    case LN_END:
  	    case LN_LAST:
  		*valueP = buf->b_ml.ml_line_count;
  		break;
  	}
  	return TCL_OK;
      }
      Tcl_ResetResult(interp);
  
      err = Tcl_GetIntFromObj(interp, obj, &i);
      if (err != TCL_OK)
  	return err;
      i = row2vim(i);
      if (i < 1  ||  i > buf->b_ml.ml_line_count)
      {
  	Tcl_SetResult(interp, _("line number out of range"), TCL_STATIC);
  	return TCL_ERROR;
      }
      *valueP = i;
      return TCL_OK;
  }
  
  /*
   * Find the first window in the window list that displays the buffer.
   */
      static win_T *
  tclfindwin(buf)
      buf_T *buf;
  {
      win_T *win;
  
      FOR_ALL_WINDOWS(win)
      {
  	if (win->w_buffer == buf)
  	    return win;
      }
      return curwin;  /* keep current window context */
  }
  
  /*
   * Do-it-all function for "::vim::command", "$buf command" and "$win command".
   */
      static int
  tcldoexcommand(interp, objc, objv, objn)
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
      int		objn;
  {
      tcl_info	saveinfo;
      int		err, flag, nobjs;
      char	*arg;
  
      nobjs = objc - objn;
      if (nobjs < 1 || nobjs > 2)
      {
  	Tcl_WrongNumArgs(interp, objn, objv, "?-quiet? exCommand");
  	return TCL_ERROR;
      }
  
      flag = 0;
      if (nobjs == 2)
      {
  	arg = Tcl_GetStringFromObj(objv[objn], NULL);
  	if (strcmp(arg, "-quiet") == 0)
  	    flag = 1;
  	else
  	{
  	    Tcl_ResetResult(interp);
  	    Tcl_AppendResult(interp, _("unknown flag: "), arg, (char *)0);
  	    return TCL_ERROR;
  	}
  	++objn;
      }
  
      memcpy(&saveinfo, &tclinfo, sizeof(tcl_info));
      tclinfo.interp = NULL;
      tclinfo.curwin = NULL;
      tclinfo.curbuf = NULL;
  
      arg = Tcl_GetStringFromObj(objv[objn], NULL);
      if (flag)
  	++emsg_off;
      do_cmdline_cmd((char_u *)arg);
      if (flag)
  	--emsg_off;
      err = vimerror(interp);
  
      /* If the ex command created a new Tcl interpreter, remove it */
      if (tclinfo.interp)
  	tcldelthisinterp();
      memcpy(&tclinfo, &saveinfo, sizeof(tcl_info));
      tclupdatevars();
  
      return err;
  }
  
  /*
   * Do-it-all function for "::vim::option", "$buf option" and "$win option".
   */
      static int
  tclsetoption(interp, objc, objv, objn)
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
      int		objn;
  {
      int		err, nobjs, idx;
      char_u	*option;
      int		isnum;
      long	lval;
      char_u	*sval;
      Tcl_Obj	*resobj;
  
      enum { OPT_OFF, OPT_ON, OPT_TOGGLE };
      static CONST84 char *optkw[] = { "off", "on", "toggle", (char *)0 };
  
      nobjs = objc - objn;
      if (nobjs != 1 && nobjs != 2)
      {
  	Tcl_WrongNumArgs(interp, objn, objv, "vimOption ?value?");
  	return TCL_ERROR;
      }
  
      option = (char_u *)Tcl_GetStringFromObj(objv[objn], NULL);
      ++objn;
      isnum = get_option_value(option, &lval, &sval, 0);
      err = TCL_OK;
      switch (isnum)
      {
  	case 0:
  	    Tcl_SetResult(interp, (char *)sval, TCL_VOLATILE);
  	    vim_free(sval);
  	    break;
  	case 1:
  	    resobj = Tcl_NewLongObj(lval);
  	    Tcl_SetObjResult(interp, resobj);
  	    break;
  	default:
  	    Tcl_SetResult(interp, _("unknown vimOption"), TCL_STATIC);
  	    return TCL_ERROR;
      }
      if (nobjs == 2)
      {
  	if (isnum)
  	{
  	    sval = NULL;    /* avoid compiler warning */
  	    err = Tcl_GetIndexFromObj(interp, objv[objn], optkw, "", 0, &idx);
  	    if (err != TCL_OK)
  	    {
  		Tcl_ResetResult(interp);
  		err = Tcl_GetLongFromObj(interp, objv[objn], &lval);
  	    }
  	    else
  	    switch (idx)
  	    {
  		case OPT_ON:
  		    lval = 1;
  		    break;
  		case OPT_OFF:
  		    lval = 0;
  		    break;
  		case OPT_TOGGLE:
  		    lval = !lval;
  		    break;
  	    }
  	}
  	else
  	    sval = (char_u *)Tcl_GetStringFromObj(objv[objn], NULL);
  	if (err == TCL_OK)
  	{
  	    set_option_value(option, lval, sval, OPT_LOCAL);
  	    err = vimerror(interp);
  	}
      }
      return err;
  }
  
  /*
   * Do-it-all function for "::vim::expr", "$buf expr" and "$win expr".
   */
      static int
  tclvimexpr(interp, objc, objv, objn)
      Tcl_Interp	*interp;
      int		objc;
      Tcl_Obj	*CONST objv[];
      int		objn;
  {
  #ifdef FEAT_EVAL
      char	*expr, *str;
  #endif
      int		err;
  
      if (objc - objn != 1)
      {
  	Tcl_WrongNumArgs(interp, objn, objv, "vimExpr");
  	return TCL_ERROR;
      }
  
  #ifdef FEAT_EVAL
      expr = Tcl_GetStringFromObj(objv[objn], NULL);
      str = (char *)eval_to_string((char_u *)expr, NULL, TRUE);
      if (str == NULL)
  	Tcl_SetResult(interp, _("invalid expression"), TCL_STATIC);
      else
  	Tcl_SetResult(interp, str, TCL_VOLATILE);
      err = vimerror(interp);
  #else
      Tcl_SetResult(interp, _("expressions disabled at compile time"), TCL_STATIC);
      err = TCL_ERROR;
  #endif
  
      return err;
  }
  
  /*
   * Check for internal vim errors.
   */
      static int
  vimerror(interp)
      Tcl_Interp *interp;
  {
      if (got_int)
      {
  	Tcl_SetResult(interp, _("keyboard interrupt"), TCL_STATIC);
  	return TCL_ERROR;
      }
      else if (did_emsg)
      {
  	Tcl_SetResult(interp, _("vim error"), TCL_STATIC);
  	return TCL_ERROR;
      }
      return TCL_OK;
  }
  
  /*
   * Functions that handle the reference lists:
   *   delref() - callback for Tcl's DeleteCommand
   *   tclgetref() - find/create Tcl command for a win_T* or buf_T* object
   *   tclgetwindow() - window frontend for tclgetref()
   *   tclgetbuffer() - buffer frontend for tclgetref()
   *   tclsetdelcmd() - add Tcl callback command to a vim object
   */
      static void
  delref(cref)
      ClientData cref;
  {
      struct ref *ref = (struct ref *)cref;
  
      if (ref->delcmd)
      {
  	Tcl_DecrRefCount(ref->delcmd);
  	ref->delcmd = NULL;
      }
      ref->interp = NULL;
  }
  
      static char *
  tclgetref(interp, refstartP, prefix, vimobj, proc)
      Tcl_Interp	*interp;
      void	**refstartP;	/* ptr to w_tcl_ref/b_tcl-ref member of
  				   win_T/buf_T struct */
      char	*prefix;	/* "win" or "buf" */
      void	*vimobj;	/* win_T* or buf_T* */
      Tcl_ObjCmdProc *proc;	/* winselfcmd or bufselfcmd */
  {
      struct ref *ref, *unused = NULL;
      static char name[VARNAME_SIZE];
      Tcl_Command cmd;
  
      ref = (struct ref *)(*refstartP);
      if (ref == &refsdeleted)
      {
  	Tcl_SetResult(interp, _("cannot create buffer/window command: object is being deleted"), TCL_STATIC);
  	return NULL;
      }
  
      while (ref != NULL)
      {
  	if (ref->interp == interp)
  	    break;
  	if (ref->interp == NULL)
  	    unused = ref;
  	ref = ref->next;
      }
  
      if (ref)
  	vim_snprintf(name, sizeof(name), "::vim::%s",
  					Tcl_GetCommandName(interp, ref->cmd));
      else
      {
  	if (unused)
  	    ref = unused;
  	else
  	{
  	    ref = (struct ref *)Tcl_Alloc(sizeof(struct ref));
  	    ref->interp = NULL;
  	    ref->next = (struct ref *)(*refstartP);
  	    (*refstartP) = (void *)ref;
  	}
  
  	/* This might break on some exotic systems... */
  	vim_snprintf(name, sizeof(name), "::vim::%s_%lx",
  					       prefix, (unsigned long)vimobj);
  	cmd = Tcl_CreateObjCommand(interp, name, proc,
  	    (ClientData)ref, (Tcl_CmdDeleteProc *)delref);
  	if (!cmd)
  	    return NULL;
  
  	ref->interp = interp;
  	ref->cmd = cmd;
  	ref->delcmd = NULL;
  	ref->vimobj = vimobj;
      }
      return name;
  }
  
      static char *
  tclgetwindow(interp, win)
      Tcl_Interp	*interp;
      win_T	*win;
  {
      return tclgetref(interp, &(win->w_tcl_ref), "win", (void *)win, winselfcmd);
  }
  
      static char *
  tclgetbuffer(interp, buf)
      Tcl_Interp	*interp;
      buf_T	*buf;
  {
      return tclgetref(interp, &(buf->b_tcl_ref), "buf", (void *)buf, bufselfcmd);
  }
  
      static int
  tclsetdelcmd(interp, reflist, vimobj, delcmd)
      Tcl_Interp	*interp;
      struct ref	*reflist;
      void	*vimobj;
      Tcl_Obj	*delcmd;
  {
      if (reflist == &refsdeleted)
      {
  	Tcl_SetResult(interp, _("cannot register callback command: buffer/window is already being deleted"), TCL_STATIC);
  	return TCL_ERROR;
      }
  
      while (reflist != NULL)
      {
  	if (reflist->interp == interp && reflist->vimobj == vimobj)
  	{
  	    if (reflist->delcmd)
  	    {
  		Tcl_DecrRefCount(reflist->delcmd);
  	    }
  	    Tcl_IncrRefCount(delcmd);
  	    reflist->delcmd = delcmd;
  	    return TCL_OK;
  	}
  	reflist = reflist->next;
      }
      /* This should never happen.  Famous last word? */
      EMSG(_("E280: TCL FATAL ERROR: reflist corrupt!? Please report this to vim-dev@vim.org"));
      Tcl_SetResult(interp, _("cannot register callback command: buffer/window reference not found"), TCL_STATIC);
      return TCL_ERROR;
  }
  
  
  /*******************************************
      I/O Channel
  ********************************************/
  
      static int
  channel_close(instance, interp)
      ClientData	instance;
      Tcl_Interp	*interp UNUSED;
  {
      int		err = 0;
  
      /* currently does nothing */
  
      if (instance != VIMOUT && instance != VIMERR)
      {
  	Tcl_SetErrno(EBADF);
  	err = EBADF;
      }
      return err;
  }
  
      static int
  channel_input(instance, buf, bufsiz, errptr)
      ClientData	instance UNUSED;
      char	*buf UNUSED;
      int		bufsiz UNUSED;
      int		*errptr;
  {
  
      /* input is currently not supported */
  
      Tcl_SetErrno(EINVAL);
      if (errptr)
  	*errptr = EINVAL;
      return -1;
  }
  
      static int
  channel_output(instance, buf, bufsiz, errptr)
      ClientData	instance;
      char	*buf;
      int		bufsiz;
      int		*errptr;
  {
      char_u	*str;
      int		result;
  
      /* The buffer is not guaranteed to be 0-terminated, and we don't if
       * there is enough room to add a '\0'.  So we have to create a copy
       * of the buffer...
       */
      str = vim_strnsave((char_u *)buf, bufsiz);
      if (!str)
      {
  	Tcl_SetErrno(ENOMEM);
  	if (errptr)
  	    *errptr = ENOMEM;
  	return -1;
      }
  
      result = bufsiz;
      if (instance == VIMOUT)
  	tclmsg((char *)str);
      else
      if (instance == VIMERR)
  	tclerrmsg((char *)str);
      else
      {
  	Tcl_SetErrno(EBADF);
  	if (errptr)
  	    *errptr = EBADF;
  	result = -1;
      }
      vim_free(str);
      return result;
  }
  
      static void
  channel_watch(instance, mask)
      ClientData	instance UNUSED;
      int		mask UNUSED;
  {
      Tcl_SetErrno(EINVAL);
  }
  
      static int
  channel_gethandle(instance, direction, handleptr)
      ClientData	instance UNUSED;
      int		direction UNUSED;
      ClientData	*handleptr UNUSED;
  {
      Tcl_SetErrno(EINVAL);
      return EINVAL;
  }
  
  
  static Tcl_ChannelType channel_type =
  {
      "vimmessage",	/* typeName */
      TCL_CHANNEL_VERSION_2, /* version */
      channel_close,	/* closeProc */
      channel_input,	/* inputProc */
      channel_output,	/* outputProc */
      NULL,		/* seekProc */
      NULL,		/* setOptionProc */
      NULL,		/* getOptionProc */
      channel_watch,	/* watchProc */
      channel_gethandle,	/* getHandleProc */
      NULL,		/* close2Proc */
      NULL,		/* blockModeProc */
  #ifdef TCL_CHANNEL_VERSION_2
      NULL,		/* flushProc */
      NULL,		/* handlerProc */
  #endif
  /* The following should not be necessary since TCL_CHANNEL_VERSION_2 was
   * set above */
  #ifdef TCL_CHANNEL_VERSION_3
      NULL,		/* wideSeekProc */
  #endif
  #ifdef TCL_CHANNEL_VERSION_4
      NULL,		/* threadActionProc */
  #endif
  #ifdef TCL_CHANNEL_VERSION_5
      NULL		/* truncateProc */
  #endif
  };
  
  /**********************************
    Interface to vim
   **********************************/
  
      static void
  tclupdatevars()
  {
      char varname[VARNAME_SIZE];	/* must be writeable */
      char *name;
  
      strcpy(varname, VAR_RANGE1);
      Tcl_UpdateLinkedVar(tclinfo.interp, varname);
      strcpy(varname, VAR_RANGE2);
      Tcl_UpdateLinkedVar(tclinfo.interp, varname);
      strcpy(varname, VAR_RANGE3);
      Tcl_UpdateLinkedVar(tclinfo.interp, varname);
  
      strcpy(varname, VAR_LBASE);
      Tcl_UpdateLinkedVar(tclinfo.interp, varname);
  
      name = tclgetbuffer(tclinfo.interp, curbuf);
      strcpy(tclinfo.curbuf, name);
      strcpy(varname, VAR_CURBUF);
      Tcl_UpdateLinkedVar(tclinfo.interp, varname);
  
      name = tclgetwindow(tclinfo.interp, curwin);
      strcpy(tclinfo.curwin, name);
      strcpy(varname, VAR_CURWIN);
      Tcl_UpdateLinkedVar(tclinfo.interp, varname);
  }
  
  
      static int
  tclinit(eap)
      exarg_T *eap;
  {
      char varname[VARNAME_SIZE];	/* Tcl_LinkVar requires writeable varname */
      char *name;
  
  #ifdef DYNAMIC_TCL
      if (!tcl_enabled(TRUE))
      {
  	EMSG(_("E571: Sorry, this command is disabled: the Tcl library could not be loaded."));
  	return FAIL;
      }
  #endif
  
      if (!tclinfo.interp)
      {
  	Tcl_Interp *interp;
  	static Tcl_Channel ch1, ch2;
  
  	/* Create replacement channels for stdout and stderr; this has to be
  	 * done each time an interpreter is created since the channels are closed
  	 * when the interpreter is deleted */
  	ch1 = Tcl_CreateChannel(&channel_type, "vimout", VIMOUT, TCL_WRITABLE);
  	ch2 = Tcl_CreateChannel(&channel_type, "vimerr", VIMERR, TCL_WRITABLE);
  	Tcl_SetStdChannel(ch1, TCL_STDOUT);
  	Tcl_SetStdChannel(ch2, TCL_STDERR);
  
  	interp = Tcl_CreateInterp();
  	Tcl_Preserve(interp);
  	if (Tcl_Init(interp) == TCL_ERROR)
  	{
  	    Tcl_Release(interp);
  	    Tcl_DeleteInterp(interp);
  	    return FAIL;
  	}
  #if 0
  	/* VIM sure is interactive */
  	Tcl_SetVar(interp, "tcl_interactive", "1", TCL_GLOBAL_ONLY);
  #endif
  
  	Tcl_SetChannelOption(interp, ch1, "-buffering", "line");
  #ifdef WIN3264
  	Tcl_SetChannelOption(interp, ch1, "-translation", "lf");
  #endif
  	Tcl_SetChannelOption(interp, ch2, "-buffering", "line");
  #ifdef WIN3264
  	Tcl_SetChannelOption(interp, ch2, "-translation", "lf");
  #endif
  
  	/* replace standard Tcl exit command */
  	Tcl_DeleteCommand(interp, "exit");
  	Tcl_CreateObjCommand(interp, "exit", exitcmd,
  	    (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
  
  	/* new commands, in ::vim namespace */
  	Tcl_CreateObjCommand(interp, "::vim::buffer", buffercmd,
  	    (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
  	Tcl_CreateObjCommand(interp, "::vim::window", windowcmd,
  	   (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
  	Tcl_CreateObjCommand(interp, "::vim::command", commandcmd,
  	   (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
  	Tcl_CreateObjCommand(interp, "::vim::beep", beepcmd,
  	   (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
  	Tcl_CreateObjCommand(interp, "::vim::option", optioncmd,
  	   (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
  	Tcl_CreateObjCommand(interp, "::vim::expr", exprcmd,
  	   (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
  
  	/* "lbase" variable */
  	tclinfo.lbase = 1;
  	strcpy(varname, VAR_LBASE);
  	Tcl_LinkVar(interp, varname, (char *)&tclinfo.lbase, TCL_LINK_INT);
  
  	/* "range" variable */
  	tclinfo.range_start = eap->line1;
  	strcpy(varname, VAR_RANGE1);
  	Tcl_LinkVar(interp, varname, (char *)&tclinfo.range_start, TCL_LINK_INT|TCL_LINK_READ_ONLY);
  	strcpy(varname, VAR_RANGE2);
  	Tcl_LinkVar(interp, varname, (char *)&tclinfo.range_start, TCL_LINK_INT|TCL_LINK_READ_ONLY);
  	tclinfo.range_end   = eap->line2;
  	strcpy(varname, VAR_RANGE3);
  	Tcl_LinkVar(interp, varname, (char *)&tclinfo.range_end, TCL_LINK_INT|TCL_LINK_READ_ONLY);
  
  	/* "current" variable */
  	tclinfo.curbuf = Tcl_Alloc(VARNAME_SIZE);
  	tclinfo.curwin = Tcl_Alloc(VARNAME_SIZE);
  	name = tclgetbuffer(interp, curbuf);
  	strcpy(tclinfo.curbuf, name);
  	strcpy(varname, VAR_CURBUF);
  	Tcl_LinkVar(interp, varname, (char *)&tclinfo.curbuf, TCL_LINK_STRING|TCL_LINK_READ_ONLY);
  	name = tclgetwindow(interp, curwin);
  	strcpy(tclinfo.curwin, name);
  	strcpy(varname, VAR_CURWIN);
  	Tcl_LinkVar(interp, varname, (char *)&tclinfo.curwin, TCL_LINK_STRING|TCL_LINK_READ_ONLY);
  
  	tclinfo.interp = interp;
      }
      else
      {
  	/* Interpreter already exists, just update variables */
  	tclinfo.range_start = row2tcl(eap->line1);
  	tclinfo.range_end = row2tcl(eap->line2);
  	tclupdatevars();
      }
  
      tclinfo.exitvalue = 0;
      return OK;
  }
  
      static void
  tclerrmsg(text)
      char *text;
  {
      char *next;
  
      while ((next=strchr(text, '\n')))
      {
  	*next++ = '\0';
  	EMSG(text);
  	text = next;
      }
      if (*text)
  	EMSG(text);
  }
  
      static void
  tclmsg(text)
      char *text;
  {
      char *next;
  
      while ((next=strchr(text, '\n')))
      {
  	*next++ = '\0';
  	MSG(text);
  	text = next;
      }
      if (*text)
  	MSG(text);
  }
  
      static void
  tcldelthisinterp()
  {
      if (!Tcl_InterpDeleted(tclinfo.interp))
  	Tcl_DeleteInterp(tclinfo.interp);
      Tcl_Release(tclinfo.interp);
      /* The interpreter is now gets deleted.  All registered commands (esp.
       * window and buffer commands) are deleted, triggering their deletion
       * callback, which deletes all refs pointing to this interpreter.
       * We could garbage-collect the unused ref structs in all windows and
       * buffers, but unless the user creates hundreds of sub-interpreters
       * all referring to lots of windows and buffers, this is hardly worth
       * the effort.  Unused refs are recycled by other interpreters, and
       * all refs are free'd when the window/buffer gets closed by vim.
       */
  
      tclinfo.interp = NULL;
      Tcl_Free(tclinfo.curbuf);
      Tcl_Free(tclinfo.curwin);
      tclinfo.curbuf = tclinfo.curwin = NULL;
  }
  
      static int
  tclexit(error)
      int error;
  {
      int newerr = OK;
  
      if (Tcl_InterpDeleted(tclinfo.interp)     /* True if we intercepted Tcl's exit command */
  #if (TCL_MAJOR_VERSION == 8 && TCL_MINOR_VERSION >= 5) || TCL_MAJOR_VERSION > 8
  	|| Tcl_LimitExceeded(tclinfo.interp)  /* True if the interpreter cannot continue */
  #endif
  	)
      {
  	char buf[50];
  
  	sprintf(buf, _("E572: exit code %d"), tclinfo.exitvalue);
  	tclerrmsg(buf);
  	if (tclinfo.exitvalue == 0)
  	{
  	    did_emsg = 0;
  	    newerr = OK;
  	}
  	else
  	    newerr = FAIL;
  
  	tcldelthisinterp();
      }
      else
      {
  	char *result;
  
  	result = (char *)Tcl_GetStringResult(tclinfo.interp);
  	if (error == TCL_OK)
  	{
  	    tclmsg(result);
  	    newerr = OK;
  	}
  	else
  	{
  	    tclerrmsg(result);
  	    newerr = FAIL;
  	}
      }
  
      return newerr;
  }
  
  /*
   * ":tcl"
   */
      void
  ex_tcl(eap)
      exarg_T *eap;
  {
      char_u	*script;
      int		err;
  
      script = script_get(eap, eap->arg);
      if (!eap->skip)
      {
  	err = tclinit(eap);
  	if (err == OK)
  	{
  	    Tcl_AllowExceptions(tclinfo.interp);
  	    if (script == NULL)
  		err = Tcl_Eval(tclinfo.interp, (char *)eap->arg);
  	    else
  		err = Tcl_Eval(tclinfo.interp, (char *)script);
  	    err = tclexit(err);
  	}
      }
      vim_free(script);
  }
  
  /*
   * ":tclfile"
   */
      void
  ex_tclfile(eap)
      exarg_T *eap;
  {
      char *file = (char *)eap->arg;
      int err;
  
      err = tclinit(eap);
      if (err == OK)
      {
  	Tcl_AllowExceptions(tclinfo.interp);
  	err = Tcl_EvalFile(tclinfo.interp, file);
  	err = tclexit(err);
      }
  }
  
  /*
   * ":tcldo"
   */
      void
  ex_tcldo(eap)
      exarg_T *eap;
  {
      char	*script, *line;
      int		err, rs, re, lnum;
      char	var_lnum[VARNAME_SIZE]; /* must be writeable memory */
      char	var_line[VARNAME_SIZE];
      linenr_T	first_line = 0;
      linenr_T	last_line = 0;
  
      rs = eap->line1;
      re = eap->line2;
      script = (char *)eap->arg;
      strcpy(var_lnum, VAR_CURLNUM);
      strcpy(var_line, VAR_CURLINE);
  
      err = tclinit(eap);
      if (err != OK)
  	return;
  
      lnum = row2tcl(rs);
      Tcl_LinkVar(tclinfo.interp, var_lnum, (char *)&lnum, TCL_LINK_INT|TCL_LINK_READ_ONLY);
      err = TCL_OK;
      if (u_save((linenr_T)(rs-1), (linenr_T)(re+1)) != OK)
      {
  	Tcl_SetResult(tclinfo.interp, _("cannot save undo information"), TCL_STATIC);
  	err = TCL_ERROR;
      }
      while (err == TCL_OK  &&  rs <= re)
      {
  	line = (char *)ml_get_buf(curbuf, (linenr_T)rs, FALSE);
  	if (!line)
  	{
  	    Tcl_SetResult(tclinfo.interp, _("cannot get line"), TCL_STATIC);
  	    err = TCL_ERROR;
  	    break;
  	}
  	Tcl_SetVar(tclinfo.interp, var_line, line, 0);
  	Tcl_AllowExceptions(tclinfo.interp);
  	err = Tcl_Eval(tclinfo.interp, script);
  	if (err != TCL_OK
  	    || Tcl_InterpDeleted(tclinfo.interp)
  #if (TCL_MAJOR_VERSION == 8 && TCL_MINOR_VERSION >= 5) || TCL_MAJOR_VERSION > 8
  	    || Tcl_LimitExceeded(tclinfo.interp)
  #endif
  	   )
  	    break;
  	line = (char *)Tcl_GetVar(tclinfo.interp, var_line, 0);
  	if (line)
  	{
  	    if (ml_replace((linenr_T)rs, (char_u *)line, TRUE) != OK)
  	    {
  		Tcl_SetResult(tclinfo.interp, _("cannot replace line"), TCL_STATIC);
  		err = TCL_ERROR;
  		break;
  	    }
  	    if (first_line == 0)
  		first_line = rs;
  	    last_line = rs;
  	}
  	++rs;
  	++lnum;
  	Tcl_UpdateLinkedVar(tclinfo.interp, var_lnum);
      }
      if (first_line)
  	changed_lines(first_line, 0, last_line + 1, (long)0);
  
      Tcl_UnsetVar(tclinfo.interp, var_line, 0);
      Tcl_UnlinkVar(tclinfo.interp, var_lnum);
      if (err == TCL_OK)
  	Tcl_ResetResult(tclinfo.interp);
  
      (void)tclexit(err);
  }
  
      static void
  tcldelallrefs(ref)
      struct ref *ref;
  {
      struct ref	*next;
      int		err;
      char	*result;
  
      while (ref != NULL)
      {
  	next = ref->next;
  	if (ref->interp)
  	{
  	    if (ref->delcmd)
  	    {
  		err = Tcl_GlobalEvalObj(ref->interp, ref->delcmd);
  		if (err != TCL_OK)
  		{
  		    result = (char *)Tcl_GetStringResult(ref->interp);
  		    if (result)
  			tclerrmsg(result);
  		}
  		Tcl_DecrRefCount(ref->delcmd);
  		ref->delcmd = NULL;
  	    }
  	    Tcl_DeleteCommandFromToken(ref->interp, ref->cmd);
  	}
  	Tcl_Free((char *)ref);
  	ref = next;
      }
  }
  
      void
  tcl_buffer_free(buf)
      buf_T *buf;
  {
      struct ref *reflist;
  
  #ifdef DYNAMIC_TCL
      if (!stubs_initialized)	/* Not using Tcl, nothing to do. */
  	return;
  #endif
  
      reflist = (struct ref *)(buf->b_tcl_ref);
      if (reflist != &refsdeleted)
      {
  	buf->b_tcl_ref = (void *)&refsdeleted;
  	tcldelallrefs(reflist);
  	buf->b_tcl_ref = NULL;
      }
  }
  
  #if defined(FEAT_WINDOWS) || defined(PROTO)
      void
  tcl_window_free(win)
      win_T *win;
  {
      struct ref *reflist;
  
  #ifdef DYNAMIC_TCL
      if (!stubs_initialized)	/* Not using Tcl, nothing to do. */
  	return;
  #endif
  
      reflist = (struct ref*)(win->w_tcl_ref);
      if (reflist != &refsdeleted)
      {
  	win->w_tcl_ref = (void *)&refsdeleted;
  	tcldelallrefs(reflist);
  	win->w_tcl_ref = NULL;
      }
  }
  #endif
  
  /* The End */
  