xref: /illumos-gate/usr/src/cmd/tbl/ti.c (revision b55148877d473978f0b46d593fd6213fa526fcc5)
1 /*
2  * Copyright 1990 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
7 /*	  All Rights Reserved  	*/
8 
9 /*
10  * Copyright (c) 1980 Regents of the University of California.
11  * All rights reserved. The Berkeley software License Agreement
12  * specifies the terms and conditions for redistribution.
13  */
14 
15 #pragma ident	"%Z%%M%	%I%	%E% SMI"
16 
17  /* ti.c: classify line intersections */
18 # include "t..c"
19 /* determine local environment for intersections */
20 
21 int
22 interv(int i, int c)
23 {
24 int ku, kl;
25 if (c>=ncol || c == 0)
26 	{
27 	if (dboxflg)
28 		{
29 		if (i==0) return(BOT);
30 		if (i>=nlin) return(TOP);
31 		return(THRU);
32 		}
33 	if (c>=ncol)
34 		return(0);
35 	}
36 ku = i>0 ? lefdata(i-1,c) : 0;
37 if (i+1 >= nlin)
38 	kl=0;
39 else
40 kl = lefdata(allh(i) ? i+1 : i, c);
41 if (ku==2 && kl==2) return(THRU);
42 if (ku ==2) return(TOP);
43 if (kl==BOT) return(2);
44 return(0);
45 }
46 
47 int
48 interh(int i, int c)
49 {
50 int kl, kr;
51 if (fullbot[i]== '=' || (dboxflg && (i==0 || i>= nlin-1)))
52 	{
53 	if (c==ncol)
54 		return(LEFT);
55 	if (c==0)
56 		return(RIGHT);
57 	return(THRU);
58 	}
59 if (i>=nlin) return(0);
60 kl = c>0 ? thish (i,c-1) : 0;
61 if (kl<=1 && i>0 && allh(up1(i)))
62 	kl = c>0 ? thish(up1(i),c-1) : 0;
63 kr = thish(i,c);
64 if (kr<=1 && i>0 && allh(up1(i)))
65 	kr = c>0 ? thish(up1(i), c) : 0;
66 if (kl== '=' && kr ==  '=') return(THRU);
67 if (kl== '=') return(LEFT);
68 if (kr== '=') return(RIGHT);
69 return(0);
70 }
71 
72 int
73 up1(int i)
74 {
75 i--;
76 while (instead[i] && i>0) i--;
77 return(i);
78 }
79