unvis.c revision 1.21
1 /* $NetBSD: unvis.c,v 1.21 2002/01/31 22:43:38 tv 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 1.21 2002/01/31 22:43:38 tv 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 50 #include <assert.h> 51 #include <ctype.h> 52 #include <stdio.h> 53 #include <vis.h> 54 55 #ifdef __weak_alias 56 __weak_alias(strunvis,_strunvis) 57 __weak_alias(unvis,_unvis) 58 #endif 59 60 #ifdef __warn_references 61 __warn_references(unvis, 62 "warning: reference to compatibility unvis(); include <vis.h> for correct reference") 63 #endif 64 65 #if !HAVE_VIS_H 66 /* 67 * decode driven by state machine 68 */ 69 #define S_GROUND 0 /* haven't seen escape char */ 70 #define S_START 1 /* start decoding special sequence */ 71 #define S_META 2 /* metachar started (M) */ 72 #define S_META1 3 /* metachar more, regular char (-) */ 73 #define S_CTRL 4 /* control char started (^) */ 74 #define S_OCTAL2 5 /* octal digit 2 */ 75 #define S_OCTAL3 6 /* octal digit 3 */ 76 77 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 78 79 int 80 unvis(cp, c, astate, flag) 81 char *cp; 82 int c; 83 int *astate, flag; 84 { 85 return __unvis13(cp, (int)c, astate, flag); 86 } 87 88 /* 89 * unvis - decode characters previously encoded by vis 90 */ 91 int 92 __unvis13(cp, c, astate, flag) 93 char *cp; 94 int c; 95 int *astate, flag; 96 { 97 98 _DIAGASSERT(cp != NULL); 99 _DIAGASSERT(astate != NULL); 100 101 if (flag & UNVIS_END) { 102 if (*astate == S_OCTAL2 || *astate == S_OCTAL3) { 103 *astate = S_GROUND; 104 return (UNVIS_VALID); 105 } 106 return (*astate == S_GROUND ? UNVIS_NOCHAR : UNVIS_SYNBAD); 107 } 108 109 switch (*astate) { 110 111 case S_GROUND: 112 *cp = 0; 113 if (c == '\\') { 114 *astate = S_START; 115 return (0); 116 } 117 *cp = c; 118 return (UNVIS_VALID); 119 120 case S_START: 121 switch(c) { 122 case '\\': 123 *cp = c; 124 *astate = S_GROUND; 125 return (UNVIS_VALID); 126 case '0': case '1': case '2': case '3': 127 case '4': case '5': case '6': case '7': 128 *cp = (c - '0'); 129 *astate = S_OCTAL2; 130 return (0); 131 case 'M': 132 *cp = (char)0200; 133 *astate = S_META; 134 return (0); 135 case '^': 136 *astate = S_CTRL; 137 return (0); 138 case 'n': 139 *cp = '\n'; 140 *astate = S_GROUND; 141 return (UNVIS_VALID); 142 case 'r': 143 *cp = '\r'; 144 *astate = S_GROUND; 145 return (UNVIS_VALID); 146 case 'b': 147 *cp = '\b'; 148 *astate = S_GROUND; 149 return (UNVIS_VALID); 150 case 'a': 151 *cp = '\007'; 152 *astate = S_GROUND; 153 return (UNVIS_VALID); 154 case 'v': 155 *cp = '\v'; 156 *astate = S_GROUND; 157 return (UNVIS_VALID); 158 case 't': 159 *cp = '\t'; 160 *astate = S_GROUND; 161 return (UNVIS_VALID); 162 case 'f': 163 *cp = '\f'; 164 *astate = S_GROUND; 165 return (UNVIS_VALID); 166 case 's': 167 *cp = ' '; 168 *astate = S_GROUND; 169 return (UNVIS_VALID); 170 case 'E': 171 *cp = '\033'; 172 *astate = S_GROUND; 173 return (UNVIS_VALID); 174 case '\n': 175 /* 176 * hidden newline 177 */ 178 *astate = S_GROUND; 179 return (UNVIS_NOCHAR); 180 case '$': 181 /* 182 * hidden marker 183 */ 184 *astate = S_GROUND; 185 return (UNVIS_NOCHAR); 186 } 187 *astate = S_GROUND; 188 return (UNVIS_SYNBAD); 189 190 case S_META: 191 if (c == '-') 192 *astate = S_META1; 193 else if (c == '^') 194 *astate = S_CTRL; 195 else { 196 *astate = S_GROUND; 197 return (UNVIS_SYNBAD); 198 } 199 return (0); 200 201 case S_META1: 202 *astate = S_GROUND; 203 *cp |= c; 204 return (UNVIS_VALID); 205 206 case S_CTRL: 207 if (c == '?') 208 *cp |= 0177; 209 else 210 *cp |= c & 037; 211 *astate = S_GROUND; 212 return (UNVIS_VALID); 213 214 case S_OCTAL2: /* second possible octal digit */ 215 if (isoctal(c)) { 216 /* 217 * yes - and maybe a third 218 */ 219 *cp = (*cp << 3) + (c - '0'); 220 *astate = S_OCTAL3; 221 return (0); 222 } 223 /* 224 * no - done with current sequence, push back passed char 225 */ 226 *astate = S_GROUND; 227 return (UNVIS_VALIDPUSH); 228 229 case S_OCTAL3: /* third possible octal digit */ 230 *astate = S_GROUND; 231 if (isoctal(c)) { 232 *cp = (*cp << 3) + (c - '0'); 233 return (UNVIS_VALID); 234 } 235 /* 236 * we were done, push back passed char 237 */ 238 return (UNVIS_VALIDPUSH); 239 240 default: 241 /* 242 * decoder in unknown state - (probably uninitialized) 243 */ 244 *astate = S_GROUND; 245 return (UNVIS_SYNBAD); 246 } 247 } 248 249 /* 250 * strunvis - decode src into dst 251 * 252 * Number of chars decoded into dst is returned, -1 on error. 253 * Dst is null terminated. 254 */ 255 256 int 257 strunvis(dst, src) 258 char *dst; 259 const char *src; 260 { 261 char c; 262 char *start = dst; 263 int state = 0; 264 265 _DIAGASSERT(src != NULL); 266 _DIAGASSERT(dst != NULL); 267 268 while ((c = *src++) != '\0') { 269 again: 270 switch (__unvis13(dst, c, &state, 0)) { 271 case UNVIS_VALID: 272 dst++; 273 break; 274 case UNVIS_VALIDPUSH: 275 dst++; 276 goto again; 277 case 0: 278 case UNVIS_NOCHAR: 279 break; 280 default: 281 return (-1); 282 } 283 } 284 if (__unvis13(dst, c, &state, UNVIS_END) == UNVIS_VALID) 285 dst++; 286 *dst = '\0'; 287 return (dst - start); 288 } 289 #endif 290
Indexes created Sun Sep 21 20:09:37 GMT 2025