ex/ex_undo.c

   1 /*-
   2  * Copyright (c) 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * %sccs.include.redist.c%
   6  */
   7
   8 #ifndef lint
   9 static char sccsid[] = "$Id: ex_undo.c,v 8.1 1993/06/09 22:26:06 bostic Exp $ (Berkeley) $Date: 1993/06/09 22:26:06 $";
  10 #endif /* not lint */
  11
  12 #include <sys/types.h>
  13
  14 #include "vi.h"
  15 #include "excmd.h"
  16
  17 /*
  18  * ex_undol -- U
  19  *      Undo changes to this line, or roll forward.
  20  */
  21 int
  22 ex_undol(sp, ep, cmdp)
  23         SCR *sp;
  24         EXF *ep;
  25         EXCMDARG *cmdp;
  26 {
  27         MARK m;
  28
  29         if (O_ISSET(sp, O_NUNDO)) {
  30                 if (log_forward(sp, ep, &m))
  31                         return (1);
  32         } else {
  33                 if (log_setline(sp, ep, &m))
  34                         return (1);
  35         }
  36
  37         sp->lno = m.lno;
  38         sp->cno = m.cno;
  39
  40         F_SET(sp, S_AUTOPRINT);
  41
  42         return (0);
  43 }
  44
  45 /*
  46  * ex_undo -- u
  47  *      Undo the last change.
  48  */
  49 int
  50 ex_undo(sp, ep, cmdp)
  51         SCR *sp;
  52         EXF *ep;
  53         EXCMDARG *cmdp;
  54 {
  55         MARK m;
  56
  57         if (O_ISSET(sp, O_NUNDO)) {
  58                 if (log_backward(sp, ep, &m))
  59                         return (1);
  60         } else {
  61                 if (!F_ISSET(ep, F_UNDO)) {
  62                         ep->lundo = UFORWARD;
  63                         F_SET(ep, F_UNDO);
  64                 }
  65
  66                 switch (ep->lundo) {
  67                 case UBACKWARD:
  68                         if (log_forward(sp, ep, &m)) {
  69                                 F_CLR(ep, F_UNDO);
  70                                 return (1);
  71                         }
  72                         ep->lundo = UFORWARD;
  73                         break;
  74                 case UFORWARD:
  75                         if (log_backward(sp, ep, &m)) {
  76                                 F_CLR(ep, F_UNDO);
  77                                 return (1);
  78                         }
  79                         ep->lundo = UBACKWARD;
  80                         break;
  81                 }
  82         }
  83         sp->lno = m.lno;
  84         sp->cno = m.cno;
  85
  86         F_SET(sp, S_AUTOPRINT);
  87
  88         return (0);
  89 }