unvis.c revision 1.14
1 /* $NetBSD: unvis.c,v 1.14 1998/12/02 19:33:28 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 1989, 1993 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 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)unvis.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: unvis.c,v 1.14 1998/12/02 19:33:28 thorpej Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #define __LIBC12_SOURCE__ 46 47 #include "namespace.h" 48 #include <sys/types.h> 49 #include <ctype.h> 50 #include <vis.h> 51 52 #ifdef __weak_alias 53 __weak_alias(strunvis,_strunvis); 54 __weak_alias(unvis,_unvis); 55 #endif 56 57 __warn_references(unvis, 58 "warning: reference to compatibility unvis(); include <vis.h> for correct reference") 59 60 /* 61 * decode driven by state machine 62 */ 63 #define S_GROUND 0 /* haven't seen escape char */ 64 #define S_START 1 /* start decoding special sequence */ 65 #define S_META 2 /* metachar started (M) */ 66 #define S_META1 3 /* metachar more, regular char (-) */ 67 #define S_CTRL 4 /* control char started (^) */ 68 #define S_OCTAL2 5 /* octal digit 2 */ 69 #define S_OCTAL3 6 /* octal digit 3 */ 70 71 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 72 73 int 74 unvis(cp, c, astate, flag) 75 char *cp; 76 int c; 77 int *astate, flag; 78 { 79 return __unvis13(cp, (int)c, astate, flag); 80 } 81 82 /* 83 * unvis - decode characters previously encoded by vis 84 */ 85 int 86 __unvis13(cp, c, astate, flag) 87 char *cp; 88 int c; 89 int *astate, flag; 90 { 91 92 if (flag & UNVIS_END) { 93 if (*astate == S_OCTAL2 || *astate == S_OCTAL3) { 94 *astate = S_GROUND; 95 return (UNVIS_VALID); 96 } 97 return (*astate == S_GROUND ? UNVIS_NOCHAR : UNVIS_SYNBAD); 98 } 99 100 switch (*astate) { 101 102 case S_GROUND: 103 *cp = 0; 104 if (c == '\\') { 105 *astate = S_START; 106 return (0); 107 } 108 *cp = c; 109 return (UNVIS_VALID); 110 111 case S_START: 112 switch(c) { 113 case '\\': 114 *cp = c; 115 *astate = S_GROUND; 116 return (UNVIS_VALID); 117 case '0': case '1': case '2': case '3': 118 case '4': case '5': case '6': case '7': 119 *cp = (c - '0'); 120 *astate = S_OCTAL2; 121 return (0); 122 case 'M': 123 *cp = (char)0200; 124 *astate = S_META; 125 return (0); 126 case '^': 127 *astate = S_CTRL; 128 return (0); 129 case 'n': 130 *cp = '\n'; 131 *astate = S_GROUND; 132 return (UNVIS_VALID); 133 case 'r': 134 *cp = '\r'; 135 *astate = S_GROUND; 136 return (UNVIS_VALID); 137 case 'b': 138 *cp = '\b'; 139 *astate = S_GROUND; 140 return (UNVIS_VALID); 141 case 'a': 142 *cp = '\007'; 143 *astate = S_GROUND; 144 return (UNVIS_VALID); 145 case 'v': 146 *cp = '\v'; 147 *astate = S_GROUND; 148 return (UNVIS_VALID); 149 case 't': 150 *cp = '\t'; 151 *astate = S_GROUND; 152 return (UNVIS_VALID); 153 case 'f': 154 *cp = '\f'; 155 *astate = S_GROUND; 156 return (UNVIS_VALID); 157 case 's': 158 *cp = ' '; 159 *astate = S_GROUND; 160 return (UNVIS_VALID); 161 case 'E': 162 *cp = '\033'; 163 *astate = S_GROUND; 164 return (UNVIS_VALID); 165 case '\n': 166 /* 167 * hidden newline 168 */ 169 *astate = S_GROUND; 170 return (UNVIS_NOCHAR); 171 case '$': 172 /* 173 * hidden marker 174 */ 175 *astate = S_GROUND; 176 return (UNVIS_NOCHAR); 177 } 178 *astate = S_GROUND; 179 return (UNVIS_SYNBAD); 180 181 case S_META: 182 if (c == '-') 183 *astate = S_META1; 184 else if (c == '^') 185 *astate = S_CTRL; 186 else { 187 *astate = S_GROUND; 188 return (UNVIS_SYNBAD); 189 } 190 return (0); 191 192 case S_META1: 193 *astate = S_GROUND; 194 *cp |= c; 195 return (UNVIS_VALID); 196 197 case S_CTRL: 198 if (c == '?') 199 *cp |= 0177; 200 else 201 *cp |= c & 037; 202 *astate = S_GROUND; 203 return (UNVIS_VALID); 204 205 case S_OCTAL2: /* second possible octal digit */ 206 if (isoctal(c)) { 207 /* 208 * yes - and maybe a third 209 */ 210 *cp = (*cp << 3) + (c - '0'); 211 *astate = S_OCTAL3; 212 return (0); 213 } 214 /* 215 * no - done with current sequence, push back passed char 216 */ 217 *astate = S_GROUND; 218 return (UNVIS_VALIDPUSH); 219 220 case S_OCTAL3: /* third possible octal digit */ 221 *astate = S_GROUND; 222 if (isoctal(c)) { 223 *cp = (*cp << 3) + (c - '0'); 224 return (UNVIS_VALID); 225 } 226 /* 227 * we were done, push back passed char 228 */ 229 return (UNVIS_VALIDPUSH); 230 231 default: 232 /* 233 * decoder in unknown state - (probably uninitialized) 234 */ 235 *astate = S_GROUND; 236 return (UNVIS_SYNBAD); 237 } 238 } 239 240 /* 241 * strunvis - decode src into dst 242 * 243 * Number of chars decoded into dst is returned, -1 on error. 244 * Dst is null terminated. 245 */ 246 247 int 248 strunvis(dst, src) 249 char *dst; 250 const char *src; 251 { 252 char c; 253 char *start = dst; 254 int state = 0; 255 256 while ((c = *src++) != '\0') { 257 again: 258 switch (__unvis13(dst, c, &state, 0)) { 259 case UNVIS_VALID: 260 dst++; 261 break; 262 case UNVIS_VALIDPUSH: 263 dst++; 264 goto again; 265 case 0: 266 case UNVIS_NOCHAR: 267 break; 268 default: 269 return (-1); 270 } 271 } 272 if (__unvis13(dst, c, &state, UNVIS_END) == UNVIS_VALID) 273 dst++; 274 *dst = '\0'; 275 return (dst - start); 276 } 277
Indexes created Sun Sep 21 18:09:52 GMT 2025