vi/v_z.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: v_z.c,v 8.5 1993/10/03 13:01:44 bostic Exp $ (Berkeley) $Date: 1993/10/03 13:01:44 $";
  10 #endif /* not lint */
  11
  12 #include <sys/types.h>
  13
  14 #include "vi.h"
  15 #include "vcmd.h"
  16
  17 /*
  18  * v_z -- [count]z[count][-.+^<CR>]
  19  *      Move the screen.
  20  */
  21 int
  22 v_z(sp, ep, vp, fm, tm, rp)
  23         SCR *sp;
  24         EXF *ep;
  25         VICMDARG *vp;
  26         MARK *fm, *tm, *rp;
  27 {
  28         recno_t last, lno;
  29
  30         /*
  31          * The first count is the line to use.  If the value doesn't
  32          * exist, use the last line.
  33          */
  34         if (F_ISSET(vp, VC_C1SET)) {
  35                 lno = vp->count;
  36                 if (file_lline(sp, ep, &last))
  37                         return (1);
  38                 if (lno > last)
  39                         lno = last;
  40         } else
  41                 lno = fm->lno;
  42
  43         /* The second count is the window size. */
  44         if (F_ISSET(vp, VC_C2SET) && set_window_size(sp, vp->count2, 0))
  45                 return (1);
  46
  47         /* Set default cursor values. */
  48         rp->lno = lno;
  49         rp->cno = fm->cno;
  50
  51         switch (vp->character) {
  52         case '-':               /* Put the line at the bottom. */
  53                 if (sp->s_fill(sp, ep, lno, P_BOTTOM))
  54                         return (1);
  55                 break;
  56         case '.':               /* Put the line in the middle. */
  57                 if (sp->s_fill(sp, ep, lno, P_MIDDLE))
  58                         return (1);
  59                 break;
  60         default:                /* Put the line at the top for <cr>. */
  61                 if (sp->special[vp->character] != K_CR &&
  62                     sp->special[vp->character] != K_NL) {
  63                         msgq(sp, M_ERR, "usage: %s.", vp->kp->usage);
  64                         return (1);
  65                 }
  66                 /* FALLTHROUGH */
  67         case '+':               /* Put the line at the top. */
  68                 if (sp->s_fill(sp, ep, lno, P_TOP))
  69                         return (1);
  70                 break;
  71         case '^':               /* Print the screen before the z- screen. */
  72                 /*
  73                  * !!!
  74                  * Historic practice isn't real clear on this one.  It seems
  75                  * that the command "70z^" is the same as ":70<cr>z-z^" with
  76                  * an off-by-one difference.  So, until I find documentation
  77                  * to the contrary, the z^ command in this implementation
  78                  * displays the screen immediately before the current one.
  79                  * Fill the screen with the selected line at the bottom, then,
  80                  * scroll the screen down a page, and move to the middle line
  81                  * of the screen.  Historic vi moved the cursor to some random
  82                  * place in the screen, as far as I can tell.
  83                  */
  84                 if (sp->s_fill(sp, ep, lno, P_BOTTOM))
  85                         return (1);
  86                 if (sp->s_down(sp, ep, rp, sp->t_maxrows - 1, 1))
  87                         return (1);
  88                 if (sp->s_position(sp, ep, rp, 0, P_MIDDLE))
  89                         return (1);
  90                 break;
  91         }
  92
  93         /* If the map changes, have to redraw the entire screen. */
  94         F_SET(sp, S_REDRAW);
  95
  96         return (0);
  97 }