1 /* $NetBSD: tscroll.c,v 1.14 2017/01/06 13:53:18 roy 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 1.14 2017/01/06 13:53:18 roy 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 #ifdef DEBUG 117 __CTRACE(__CTRACE_MISC, 118 "__parse_cap: %%n, val = %d\n", n); 119 #endif 120 } 121 n ^= 0140; 122 continue; 123 case 'd': 124 if (!have_input) { 125 n = va_arg(ap, int); 126 have_input = 1; 127 #ifdef DEBUG 128 __CTRACE(__CTRACE_MISC, 129 "__parse_cap: %%d, val = %d\n", n); 130 #endif 131 } 132 if (n < 10) 133 goto one; 134 if (n < 100) 135 goto two; 136 /* FALLTHROUGH */ 137 case '3': 138 if (!have_input) { 139 n = va_arg(ap, int); 140 have_input = 1; 141 #ifdef DEBUG 142 __CTRACE(__CTRACE_MISC, 143 "__parse_cap: %%3, val = %d\n", n); 144 #endif 145 } 146 *dp++ = (n / 100) | '0'; 147 n %= 100; 148 /* FALLTHROUGH */ 149 case '2': 150 if (!have_input) { 151 n = va_arg(ap, int); 152 have_input = 1; 153 #ifdef DEBUG 154 __CTRACE(__CTRACE_MISC, 155 "__parse_cap: %%2, val = %d\n", n); 156 #endif 157 } 158 two: *dp++ = n / 10 | '0'; 159 one: *dp++ = n % 10 | '0'; 160 have_input = 0; 161 continue; 162 case '>': 163 if (!have_input) { 164 n = va_arg(ap, int); 165 have_input = 1; 166 #ifdef DEBUG 167 __CTRACE(__CTRACE_MISC, 168 "__parse_cap: %%>, val = %d\n", n); 169 #endif 170 } 171 if (n > *cap++) 172 n += *cap++; 173 else 174 cap++; 175 continue; 176 case '+': 177 if (!have_input) { 178 n = va_arg(ap, int); 179 have_input = 1; 180 #ifdef DEBUG 181 __CTRACE(__CTRACE_MISC, 182 "__parse_cap: %%+, val = %d\n", n); 183 #endif 184 } 185 n += *cap++; 186 /* FALLTHROUGH */ 187 case '.': 188 if (!have_input) { 189 n = va_arg(ap, int); 190 have_input = 1; 191 #ifdef DEBUG 192 __CTRACE(__CTRACE_MISC, 193 "__parse_cap: %%., val = %d\n", n); 194 #endif 195 } 196 *dp++ = n; 197 have_input = 0; 198 continue; 199 case 'i': 200 if (!have_input) { 201 n = va_arg(ap, int); 202 have_input = 1; 203 #ifdef DEBUG 204 __CTRACE(__CTRACE_MISC, 205 "__parse_cap: %%i, val = %d\n", n); 206 #endif 207 } 208 n++; 209 continue; 210 case '%': 211 *dp++ = c; 212 continue; 213 case 'B': 214 if (!have_input) { 215 n = va_arg(ap, int); 216 have_input = 1; 217 #ifdef DEBUG 218 __CTRACE(__CTRACE_MISC, 219 "__parse_cap: %%B, val = %d\n", n); 220 #endif 221 } 222 n = (n / 10 << 4) + n % 10; 223 continue; 224 case 'D': 225 if (!have_input) { 226 n = va_arg(ap, int); 227 have_input = 1; 228 #ifdef DEBUG 229 __CTRACE(__CTRACE_MISC, 230 "__parse_cap: %%D, val = %d\n", n); 231 #endif 232 } 233 n = n - 2 * (n % 16); 234 continue; 235 /* 236 * XXX 237 * System V terminfo files have lots of extra gunk. 238 * The only other one we've seen in capability strings 239 * is %pN, and it seems to work okay if we ignore it. 240 */ 241 case 'p': 242 ++cap; 243 continue; 244 default: 245 goto err; 246 } 247 } 248 *dp = '\0'; 249 va_end(ap); 250 return result; 251 252 err: va_end(ap); 253 return (char *)"\0"; 254 } 255