1 /* $NetBSD: tscroll.c,v 1.15 2021/09/06 07:03:50 rin 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 34 #ifndef lint 35 #if 0 36 static char sccsid[] = "@(#)tscroll.c 8.4 (Berkeley) 7/27/94"; 37 #else 38 __RCSID("$NetBSD: tscroll.c,v 1.15 2021/09/06 07:03:50 rin Exp $"); 39 #endif 40 #endif /* not lint */ 41 42 #include <string.h> 43 #include <stdarg.h> 44 #include "curses.h" 45 #include "curses_private.h" 46 47 #define MAXRETURNSIZE 64 48 49 char * 50 __tscroll(const char *cap, int n1, int n2) 51 { 52 53 return __parse_cap(cap, n1, n2); 54 } 55 56 /* 57 * Routines to parse capabilities. Derived from tgoto.c in termcap(3) 58 * library. Cap is a string containing printf type escapes to allow 59 * scrolling. The following escapes are defined for substituting n: 60 * 61 * %d as in printf 62 * %2 like %2d 63 * %3 like %3d 64 * %. gives %c hacking special case characters 65 * %+x like %c but adding x first 66 * 67 * The codes below affect the state but don't use up a value. 68 * 69 * %>xy if value > x add y 70 * %i increments n 71 * %% gives % 72 * %B BCD (2 decimal digits encoded in one byte) 73 * %D Delta Data (backwards bcd) 74 * 75 * all other characters are ``self-inserting''. 76 * 77 * XXX: 78 * %r reverse order of two parameters 79 * is also defined but we don't support it (yet). 80 */ 81 char * 82 __parse_cap (char const *cap, ...) 83 { 84 va_list ap; 85 static char result[MAXRETURNSIZE]; 86 int c, n; 87 char *dp; 88 int have_input; 89 90 va_start (ap, cap); 91 n = 0; /* XXX gcc -Wuninitialized */ 92 93 if (cap == NULL) 94 goto err; 95 #ifdef DEBUG 96 { 97 int i; 98 99 __CTRACE(__CTRACE_MISC, "__parse_cap: cap = "); 100 for (i = 0; i < strlen(cap); i++) 101 __CTRACE(__CTRACE_MISC, "%s", unctrl(cap[i])); 102 __CTRACE(__CTRACE_MISC, "\n"); 103 } 104 #endif 105 have_input = 0; 106 for (dp = result; (c = *cap++) != '\0';) { 107 if (c != '%') { 108 *dp++ = c; 109 continue; 110 } 111 switch (c = *cap++) { 112 case 'n': 113 if (!have_input) { 114 n = va_arg(ap, int); 115 have_input = 1; 116 __CTRACE(__CTRACE_MISC, 117 "__parse_cap: %%n, val = %d\n", n); 118 } 119 n ^= 0140; 120 continue; 121 case 'd': 122 if (!have_input) { 123 n = va_arg(ap, int); 124 have_input = 1; 125 __CTRACE(__CTRACE_MISC, 126 "__parse_cap: %%d, val = %d\n", n); 127 } 128 if (n < 10) 129 goto one; 130 if (n < 100) 131 goto two; 132 /* FALLTHROUGH */ 133 case '3': 134 if (!have_input) { 135 n = va_arg(ap, int); 136 have_input = 1; 137 __CTRACE(__CTRACE_MISC, 138 "__parse_cap: %%3, val = %d\n", n); 139 } 140 *dp++ = (n / 100) | '0'; 141 n %= 100; 142 /* FALLTHROUGH */ 143 case '2': 144 if (!have_input) { 145 n = va_arg(ap, int); 146 have_input = 1; 147 __CTRACE(__CTRACE_MISC, 148 "__parse_cap: %%2, val = %d\n", n); 149 } 150 two: *dp++ = n / 10 | '0'; 151 one: *dp++ = n % 10 | '0'; 152 have_input = 0; 153 continue; 154 case '>': 155 if (!have_input) { 156 n = va_arg(ap, int); 157 have_input = 1; 158 __CTRACE(__CTRACE_MISC, 159 "__parse_cap: %%>, val = %d\n", n); 160 } 161 if (n > *cap++) 162 n += *cap++; 163 else 164 cap++; 165 continue; 166 case '+': 167 if (!have_input) { 168 n = va_arg(ap, int); 169 have_input = 1; 170 __CTRACE(__CTRACE_MISC, 171 "__parse_cap: %%+, val = %d\n", n); 172 } 173 n += *cap++; 174 /* FALLTHROUGH */ 175 case '.': 176 if (!have_input) { 177 n = va_arg(ap, int); 178 have_input = 1; 179 __CTRACE(__CTRACE_MISC, 180 "__parse_cap: %%., val = %d\n", n); 181 } 182 *dp++ = n; 183 have_input = 0; 184 continue; 185 case 'i': 186 if (!have_input) { 187 n = va_arg(ap, int); 188 have_input = 1; 189 __CTRACE(__CTRACE_MISC, 190 "__parse_cap: %%i, val = %d\n", n); 191 } 192 n++; 193 continue; 194 case '%': 195 *dp++ = c; 196 continue; 197 case 'B': 198 if (!have_input) { 199 n = va_arg(ap, int); 200 have_input = 1; 201 __CTRACE(__CTRACE_MISC, 202 "__parse_cap: %%B, val = %d\n", n); 203 } 204 n = (n / 10 << 4) + n % 10; 205 continue; 206 case 'D': 207 if (!have_input) { 208 n = va_arg(ap, int); 209 have_input = 1; 210 __CTRACE(__CTRACE_MISC, 211 "__parse_cap: %%D, val = %d\n", n); 212 } 213 n = n - 2 * (n % 16); 214 continue; 215 /* 216 * XXX 217 * System V terminfo files have lots of extra gunk. 218 * The only other one we've seen in capability strings 219 * is %pN, and it seems to work okay if we ignore it. 220 */ 221 case 'p': 222 ++cap; 223 continue; 224 default: 225 goto err; 226 } 227 } 228 *dp = '\0'; 229 va_end(ap); 230 return result; 231 232 err: va_end(ap); 233 return (char *)"\0"; 234 } 235