unvis.c revision 1.22
1 /* $NetBSD: unvis.c,v 1.22 2002/03/23 17:38:27 christos 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 1.22 2002/03/23 17:38:27 christos 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 #define S_HEX1 7 /* hex digit */ 77 #define S_HEX2 8 /* hex digit 2 */ 78 79 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 80 #define xtod(c) (isdigit(c) ? (c - '0') : ((tolower(c) - 'a') + 10)) 81 82 int 83 unvis(cp, c, astate, flag) 84 char *cp; 85 int c; 86 int *astate, flag; 87 { 88 return __unvis13(cp, (int)c, astate, flag); 89 } 90 91 /* 92 * unvis - decode characters previously encoded by vis 93 */ 94 int 95 __unvis13(cp, c, astate, flag) 96 char *cp; 97 int c; 98 int *astate, flag; 99 { 100 101 _DIAGASSERT(cp != NULL); 102 _DIAGASSERT(astate != NULL); 103 104 if (flag & UNVIS_END) { 105 if (*astate == S_OCTAL2 || *astate == S_OCTAL3 106 || *astate == S_HEX2) { 107 *astate = S_GROUND; 108 return (UNVIS_VALID); 109 } 110 return (*astate == S_GROUND ? UNVIS_NOCHAR : UNVIS_SYNBAD); 111 } 112 113 switch (*astate) { 114 115 case S_GROUND: 116 *cp = 0; 117 if (c == '\\') { 118 *astate = S_START; 119 return (0); 120 } 121 if ((flag & VIS_HTTPSTYLE) && c == '%') { 122 *astate = S_HEX1; 123 return (0); 124 } 125 *cp = c; 126 return (UNVIS_VALID); 127 128 case S_START: 129 switch(c) { 130 case '\\': 131 *cp = c; 132 *astate = S_GROUND; 133 return (UNVIS_VALID); 134 case '0': case '1': case '2': case '3': 135 case '4': case '5': case '6': case '7': 136 *cp = (c - '0'); 137 *astate = S_OCTAL2; 138 return (0); 139 case 'M': 140 *cp = (char)0200; 141 *astate = S_META; 142 return (0); 143 case '^': 144 *astate = S_CTRL; 145 return (0); 146 case 'n': 147 *cp = '\n'; 148 *astate = S_GROUND; 149 return (UNVIS_VALID); 150 case 'r': 151 *cp = '\r'; 152 *astate = S_GROUND; 153 return (UNVIS_VALID); 154 case 'b': 155 *cp = '\b'; 156 *astate = S_GROUND; 157 return (UNVIS_VALID); 158 case 'a': 159 *cp = '\007'; 160 *astate = S_GROUND; 161 return (UNVIS_VALID); 162 case 'v': 163 *cp = '\v'; 164 *astate = S_GROUND; 165 return (UNVIS_VALID); 166 case 't': 167 *cp = '\t'; 168 *astate = S_GROUND; 169 return (UNVIS_VALID); 170 case 'f': 171 *cp = '\f'; 172 *astate = S_GROUND; 173 return (UNVIS_VALID); 174 case 's': 175 *cp = ' '; 176 *astate = S_GROUND; 177 return (UNVIS_VALID); 178 case 'E': 179 *cp = '\033'; 180 *astate = S_GROUND; 181 return (UNVIS_VALID); 182 case '\n': 183 /* 184 * hidden newline 185 */ 186 *astate = S_GROUND; 187 return (UNVIS_NOCHAR); 188 case '$': 189 /* 190 * hidden marker 191 */ 192 *astate = S_GROUND; 193 return (UNVIS_NOCHAR); 194 } 195 *astate = S_GROUND; 196 return (UNVIS_SYNBAD); 197 198 case S_META: 199 if (c == '-') 200 *astate = S_META1; 201 else if (c == '^') 202 *astate = S_CTRL; 203 else { 204 *astate = S_GROUND; 205 return (UNVIS_SYNBAD); 206 } 207 return (0); 208 209 case S_META1: 210 *astate = S_GROUND; 211 *cp |= c; 212 return (UNVIS_VALID); 213 214 case S_CTRL: 215 if (c == '?') 216 *cp |= 0177; 217 else 218 *cp |= c & 037; 219 *astate = S_GROUND; 220 return (UNVIS_VALID); 221 222 case S_OCTAL2: /* second possible octal digit */ 223 if (isoctal(c)) { 224 /* 225 * yes - and maybe a third 226 */ 227 *cp = (*cp << 3) + (c - '0'); 228 *astate = S_OCTAL3; 229 return (0); 230 } 231 /* 232 * no - done with current sequence, push back passed char 233 */ 234 *astate = S_GROUND; 235 return (UNVIS_VALIDPUSH); 236 237 case S_OCTAL3: /* third possible octal digit */ 238 *astate = S_GROUND; 239 if (isoctal(c)) { 240 *cp = (*cp << 3) + (c - '0'); 241 return (UNVIS_VALID); 242 } 243 /* 244 * we were done, push back passed char 245 */ 246 return (UNVIS_VALIDPUSH); 247 case S_HEX1: 248 if (isxdigit(c)) { 249 *cp = xtod(c); 250 *astate = S_HEX2; 251 return (0); 252 } 253 /* 254 * no - done with current sequence, push back passed char 255 */ 256 *astate = S_GROUND; 257 return (UNVIS_VALIDPUSH); 258 case S_HEX2: 259 *astate = S_GROUND; 260 if (isxdigit(c)) { 261 *cp = xtod(c) | (*cp << 4); 262 return (UNVIS_VALID); 263 } 264 return (UNVIS_VALIDPUSH); 265 default: 266 /* 267 * decoder in unknown state - (probably uninitialized) 268 */ 269 *astate = S_GROUND; 270 return (UNVIS_SYNBAD); 271 } 272 } 273 274 /* 275 * strunvis - decode src into dst 276 * 277 * Number of chars decoded into dst is returned, -1 on error. 278 * Dst is null terminated. 279 */ 280 281 int 282 strunvisx(dst, src, flag) 283 char *dst; 284 const char *src; 285 int flag; 286 { 287 char c; 288 char *start = dst; 289 int state = 0; 290 291 _DIAGASSERT(src != NULL); 292 _DIAGASSERT(dst != NULL); 293 294 while ((c = *src++) != '\0') { 295 again: 296 switch (__unvis13(dst, c, &state, flag)) { 297 case UNVIS_VALID: 298 dst++; 299 break; 300 case UNVIS_VALIDPUSH: 301 dst++; 302 goto again; 303 case 0: 304 case UNVIS_NOCHAR: 305 break; 306 default: 307 return (-1); 308 } 309 } 310 if (__unvis13(dst, c, &state, UNVIS_END) == UNVIS_VALID) 311 dst++; 312 *dst = '\0'; 313 return (dst - start); 314 } 315 316 int 317 strunvis(dst, src) 318 char *dst; 319 const char *src; 320 { 321 return strunvisx(dst, src, 0); 322 } 323 #endif 324
Indexes created Mon Sep 22 05:09:51 GMT 2025