external/bsd/nvi/dist/ex/ex_z.c

   1 /*      $NetBSD: ex_z.c,v 1.3 2014/01/26 21:43:45 christos Exp $ */
   2 /*-
   3  * Copyright (c) 1993, 1994
   4  *      The Regents of the University of California.  All rights reserved.
   5  * Copyright (c) 1993, 1994, 1995, 1996
   6  *      Keith Bostic.  All rights reserved.
   7  *
   8  * See the LICENSE file for redistribution information.
   9  */
  10
  11 #include "config.h"
  12
  13 #include <sys/cdefs.h>
  14 #if 0
  15 #ifndef lint
  16 static const char sccsid[] = "Id: ex_z.c,v 10.12 2001/06/25 15:19:22 skimo Exp  (Berkeley) Date: 2001/06/25 15:19:22 ";
  17 #endif /* not lint */
  18 #else
  19 __RCSID("$NetBSD: ex_z.c,v 1.3 2014/01/26 21:43:45 christos Exp $");
  20 #endif
  21
  22 #include <sys/types.h>
  23 #include <sys/queue.h>
  24
  25 #include <bitstring.h>
  26 #include <limits.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30
  31 #include "../common/common.h"
  32
  33 /*
  34  * ex_z -- :[line] z [^-.+=] [count] [flags]
  35  *      Adjust window.
  36  *
  37  * PUBLIC: int ex_z __P((SCR *, EXCMD *));
  38  */
  39 int
  40 ex_z(SCR *sp, EXCMD *cmdp)
  41 {
  42         MARK abm;
  43         db_recno_t cnt, equals, lno;
  44         int eofcheck;
  45
  46         NEEDFILE(sp, cmdp);
  47
  48         /*
  49          * !!!
  50          * If no count specified, use either two times the size of the
  51          * scrolling region, or the size of the window option.  POSIX
  52          * 1003.2 claims that the latter is correct, but historic ex/vi
  53          * documentation and practice appear to use the scrolling region.
  54          * I'm using the window size as it means that the entire screen
  55          * is used instead of losing a line to roundoff.  Note, we drop
  56          * a line from the cnt if using the window size to leave room for
  57          * the next ex prompt.
  58          */
  59         if (FL_ISSET(cmdp->iflags, E_C_COUNT))
  60                 cnt = cmdp->count;
  61         else
  62 #ifdef HISTORIC_PRACTICE
  63                 cnt = O_VAL(sp, O_SCROLL) * 2;
  64 #else
  65                 cnt = O_VAL(sp, O_WINDOW) - 1;
  66 #endif
  67
  68         equals = 0;
  69         eofcheck = 0;
  70         lno = cmdp->addr1.lno;
  71
  72         switch (FL_ISSET(cmdp->iflags,
  73             E_C_CARAT | E_C_DASH | E_C_DOT | E_C_EQUAL | E_C_PLUS)) {
  74         case E_C_CARAT:         /* Display cnt * 2 before the line. */
  75                 eofcheck = 1;
  76                 if (lno > cnt * 2)
  77                         cmdp->addr1.lno = (lno - cnt * 2) + 1;
  78                 else
  79                         cmdp->addr1.lno = 1;
  80                 cmdp->addr2.lno = (cmdp->addr1.lno + cnt) - 1;
  81                 break;
  82         case E_C_DASH:          /* Line goes at the bottom of the screen. */
  83                 cmdp->addr1.lno = lno > cnt ? (lno - cnt) + 1 : 1;
  84                 cmdp->addr2.lno = lno;
  85                 break;
  86         case E_C_DOT:           /* Line goes in the middle of the screen. */
  87                 /*
  88                  * !!!
  89                  * Historically, the "middleness" of the line overrode the
  90                  * count, so that "3z.19" or "3z.20" would display the first
  91                  * 12 lines of the file, i.e. (N - 1) / 2 lines before and
  92                  * after the specified line.
  93                  */
  94                 eofcheck = 1;
  95                 cnt = (cnt - 1) / 2;
  96                 cmdp->addr1.lno = lno > cnt ? lno - cnt : 1;
  97                 cmdp->addr2.lno = lno + cnt;
  98
  99                 /*
 100                  * !!!
 101                  * Historically, z. set the absolute cursor mark.
 102                  */
 103                 abm.lno = sp->lno;
 104                 abm.cno = sp->cno;
 105                 (void)mark_set(sp, ABSMARK1, &abm, 1);
 106                 break;
 107         case E_C_EQUAL:         /* Center with hyphens. */
 108                 /*
 109                  * !!!
 110                  * Strangeness.  The '=' flag is like the '.' flag (see the
 111                  * above comment, it applies here as well) but with a special
 112                  * little hack.  Print out lines of hyphens before and after
 113                  * the specified line.  Additionally, the cursor remains set
 114                  * on that line.
 115                  */
 116                 eofcheck = 1;
 117                 cnt = (cnt - 1) / 2;
 118                 cmdp->addr1.lno = lno > cnt ? lno - cnt : 1;
 119                 cmdp->addr2.lno = lno - 1;
 120                 if (ex_pr(sp, cmdp))
 121                         return (1);
 122                 (void)ex_puts(sp, "----------------------------------------\n");
 123                 cmdp->addr2.lno = cmdp->addr1.lno = equals = lno;
 124                 if (ex_pr(sp, cmdp))
 125                         return (1);
 126                 (void)ex_puts(sp, "----------------------------------------\n");
 127                 cmdp->addr1.lno = lno + 1;
 128                 cmdp->addr2.lno = (lno + cnt) - 1;
 129                 break;
 130         default:
 131                 /* If no line specified, move to the next one. */
 132                 if (F_ISSET(cmdp, E_ADDR_DEF))
 133                         ++lno;
 134                 /* FALLTHROUGH */
 135         case E_C_PLUS:          /* Line goes at the top of the screen. */
 136                 eofcheck = 1;
 137                 cmdp->addr1.lno = lno;
 138                 cmdp->addr2.lno = (lno + cnt) - 1;
 139                 break;
 140         }
 141
 142         if (eofcheck) {
 143                 if (db_last(sp, &lno))
 144                         return (1);
 145                 if (cmdp->addr2.lno > lno)
 146                         cmdp->addr2.lno = lno;
 147         }
 148
 149         if (ex_pr(sp, cmdp))
 150                 return (1);
 151         if (equals)
 152                 sp->lno = equals;
 153         return (0);
 154 }