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
ex_z(SCR * sp,EXCMD * cmdp)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 }
155