Oh GACK! src-clean doesn't quite work that easily since cleandist rebuilds the

[unix-history] / usr.bin / vi / nex / ex_undo.c

/*-
* Copyright (c) 1992, 1993
*      The Regents of the University of California.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*      This product includes software developed by the University of
*      California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#ifndef lint
static char sccsid[] = "@(#)ex_undo.c   8.4 (Berkeley) 12/29/93";
#endif /* not lint */

#include <sys/types.h>

#include "vi.h"
#include "excmd.h"

/*
* ex_undol -- U
*      Undo changes to this line.
*/
int
ex_undol(sp, ep, cmdp)
       SCR *sp;
       EXF *ep;
       EXCMDARG *cmdp;
{
       if (log_setline(sp, ep))
               return (1);

       sp->cno = 0;
       return (0);
}

/*
* ex_undo -- u
*      Undo the last change.
*/
int
ex_undo(sp, ep, cmdp)
       SCR *sp;
       EXF *ep;
       EXCMDARG *cmdp;
{
       MARK m;

       /*
        * !!!
        * Multiple undo isn't available in ex, as there's no '.' command.
        * Whether 'u' is undo or redo is toggled each time, unless there
        * was a change since the last undo, in which case it's an undo.
        */
       if (!F_ISSET(ep, F_UNDO)) {
               F_SET(ep, F_UNDO);
               ep->lundo = FORWARD;
       }
       switch (ep->lundo) {
       case BACKWARD:
               if (log_forward(sp, ep, &m))
                       return (1);
               ep->lundo = FORWARD;
               break;
       case FORWARD:
               if (log_backward(sp, ep, &m))
                       return (1);
               ep->lundo = BACKWARD;
               break;
       case NOTSET:
               abort();
       }
       sp->lno = m.lno;
       sp->cno = m.cno;
       return (0);
}