1 /* $NetBSD: tscroll.c,v 1.4 1997/07/22 07:37:08 mikel Exp $ */ 2 3 /*- 4 * Copyright (c) 1992, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)tscroll.c 8.4 (Berkeley) 7/27/94"; 40 #else 41 __RCSID("$NetBSD: tscroll.c,v 1.4 1997/07/22 07:37:08 mikel Exp $"); 42 #endif 43 #endif /* not lint */ 44 45 #include "curses.h" 46 47 #define MAXRETURNSIZE 64 48 49 /* 50 * Routine to perform scrolling. Derived from tgoto.c in tercamp(3) 51 * library. Cap is a string containing printf type escapes to allow 52 * scrolling. The following escapes are defined for substituting n: 53 * 54 * %d as in printf 55 * %2 like %2d 56 * %3 like %3d 57 * %. gives %c hacking special case characters 58 * %+x like %c but adding x first 59 * 60 * The codes below affect the state but don't use up a value. 61 * 62 * %>xy if value > x add y 63 * %i increments n 64 * %% gives % 65 * %B BCD (2 decimal digits encoded in one byte) 66 * %D Delta Data (backwards bcd) 67 * 68 * all other characters are ``self-inserting''. 69 */ 70 char * 71 __tscroll(cap, n1, n2) 72 const char *cap; 73 int n1, n2; 74 { 75 static char result[MAXRETURNSIZE]; 76 int c, n; 77 char *dp; 78 79 if (cap == NULL) 80 goto err; 81 for (n = n1, dp = result; (c = *cap++) != '\0';) { 82 if (c != '%') { 83 *dp++ = c; 84 continue; 85 } 86 switch (c = *cap++) { 87 case 'n': 88 n ^= 0140; 89 continue; 90 case 'd': 91 if (n < 10) 92 goto one; 93 if (n < 100) 94 goto two; 95 /* FALLTHROUGH */ 96 case '3': 97 *dp++ = (n / 100) | '0'; 98 n %= 100; 99 /* FALLTHROUGH */ 100 case '2': 101 two: *dp++ = n / 10 | '0'; 102 one: *dp++ = n % 10 | '0'; 103 n = n2; 104 continue; 105 case '>': 106 if (n > *cap++) 107 n += *cap++; 108 else 109 cap++; 110 continue; 111 case '+': 112 n += *cap++; 113 /* FALLTHROUGH */ 114 case '.': 115 *dp++ = n; 116 continue; 117 case 'i': 118 n++; 119 continue; 120 case '%': 121 *dp++ = c; 122 continue; 123 case 'B': 124 n = (n / 10 << 4) + n % 10; 125 continue; 126 case 'D': 127 n = n - 2 * (n % 16); 128 continue; 129 /* 130 * XXX 131 * System V terminfo files have lots of extra gunk. 132 * The only one we've seen in scrolling strings is 133 * %pN, and it seems to work okay if we ignore it. 134 */ 135 case 'p': 136 ++cap; 137 continue; 138 default: 139 goto err; 140 } 141 } 142 *dp = '\0'; 143 return (result); 144 145 err: return("curses: __tscroll failed"); 146 } 147