1 /*-
2 * Copyright (c) 1992, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #ifndef lint
31 static char sccsid[] = "@(#)tscroll.c 8.4 (Berkeley) 7/27/94";
32 #endif /* not lint */
33
34 #include "curses.h"
35
36 #define MAXRETURNSIZE 64
37
38 /*
39 * Routine to perform scrolling. Derived from tgoto.c in tercamp(3)
40 * library. Cap is a string containing printf type escapes to allow
41 * scrolling. The following escapes are defined for substituting n:
42 *
43 * %d as in printf
44 * %2 like %2d
45 * %3 like %3d
46 * %. gives %c hacking special case characters
47 * %+x like %c but adding x first
48 *
49 * The codes below affect the state but don't use up a value.
50 *
51 * %>xy if value > x add y
52 * %i increments n
53 * %% gives %
54 * %B BCD (2 decimal digits encoded in one byte)
55 * %D Delta Data (backwards bcd)
56 *
57 * all other characters are ``self-inserting''.
58 */
59 char *
__tscroll(cap,n1,n2)60 __tscroll(cap, n1, n2)
61 const char *cap;
62 int n1, n2;
63 {
64 static char result[MAXRETURNSIZE];
65 int c, n;
66 char *dp;
67
68 if (cap == NULL)
69 goto err;
70 for (n = n1, dp = result; (c = *cap++) != '\0';) {
71 if (c != '%') {
72 *dp++ = c;
73 continue;
74 }
75 switch (c = *cap++) {
76 case 'n':
77 n ^= 0140;
78 continue;
79 case 'd':
80 if (n < 10)
81 goto one;
82 if (n < 100)
83 goto two;
84 /* FALLTHROUGH */
85 case '3':
86 *dp++ = (n / 100) | '0';
87 n %= 100;
88 /* FALLTHROUGH */
89 case '2':
90 two: *dp++ = n / 10 | '0';
91 one: *dp++ = n % 10 | '0';
92 n = n2;
93 continue;
94 case '>':
95 if (n > *cap++)
96 n += *cap++;
97 else
98 cap++;
99 continue;
100 case '+':
101 n += *cap++;
102 /* FALLTHROUGH */
103 case '.':
104 *dp++ = n;
105 continue;
106 case 'i':
107 n++;
108 continue;
109 case '%':
110 *dp++ = c;
111 continue;
112 case 'B':
113 n = (n / 10 << 4) + n % 10;
114 continue;
115 case 'D':
116 n = n - 2 * (n % 16);
117 continue;
118 /*
119 * XXX
120 * System V terminfo files have lots of extra gunk.
121 * The only one we've seen in scrolling strings is
122 * %pN, and it seems to work okay if we ignore it.
123 */
124 case 'p':
125 ++cap;
126 continue;
127 default:
128 goto err;
129 }
130 }
131 *dp = '\0';
132 return (result);
133
134 err: return("curses: __tscroll failed");
135 }
136