unvis.c revision 1.24
1 /* $NetBSD: unvis.c,v 1.24 2003/08/07 16:42:59 agc 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. 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 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char sccsid[] = "@(#)unvis.c 8.1 (Berkeley) 6/4/93"; 36 #else 37 __RCSID("$NetBSD: unvis.c,v 1.24 2003/08/07 16:42:59 agc Exp $"); 38 #endif 39 #endif /* LIBC_SCCS and not lint */ 40 41 #define __LIBC12_SOURCE__ 42 43 #include "namespace.h" 44 #include <sys/types.h> 45 46 #include <assert.h> 47 #include <ctype.h> 48 #include <stdio.h> 49 #include <vis.h> 50 51 #ifdef __weak_alias 52 __weak_alias(strunvis,_strunvis) 53 __weak_alias(unvis,_unvis) 54 #endif 55 56 #ifdef __warn_references 57 __warn_references(unvis, 58 "warning: reference to compatibility unvis(); include <vis.h> for correct reference") 59 #endif 60 61 #if !HAVE_VIS 62 /* 63 * decode driven by state machine 64 */ 65 #define S_GROUND 0 /* haven't seen escape char */ 66 #define S_START 1 /* start decoding special sequence */ 67 #define S_META 2 /* metachar started (M) */ 68 #define S_META1 3 /* metachar more, regular char (-) */ 69 #define S_CTRL 4 /* control char started (^) */ 70 #define S_OCTAL2 5 /* octal digit 2 */ 71 #define S_OCTAL3 6 /* octal digit 3 */ 72 #define S_HEX1 7 /* hex digit */ 73 #define S_HEX2 8 /* hex digit 2 */ 74 75 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 76 #define xtod(c) (isdigit(c) ? (c - '0') : ((tolower(c) - 'a') + 10)) 77 78 int 79 unvis(cp, c, astate, flag) 80 char *cp; 81 int c; 82 int *astate, flag; 83 { 84 return __unvis13(cp, (int)c, astate, flag); 85 } 86 87 /* 88 * unvis - decode characters previously encoded by vis 89 */ 90 int 91 __unvis13(cp, c, astate, flag) 92 char *cp; 93 int c; 94 int *astate, flag; 95 { 96 97 _DIAGASSERT(cp != NULL); 98 _DIAGASSERT(astate != NULL); 99 100 if (flag & UNVIS_END) { 101 if (*astate == S_OCTAL2 || *astate == S_OCTAL3 102 || *astate == S_HEX2) { 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 if ((flag & VIS_HTTPSTYLE) && c == '%') { 118 *astate = S_HEX1; 119 return (0); 120 } 121 *cp = c; 122 return (UNVIS_VALID); 123 124 case S_START: 125 switch(c) { 126 case '\\': 127 *cp = c; 128 *astate = S_GROUND; 129 return (UNVIS_VALID); 130 case '0': case '1': case '2': case '3': 131 case '4': case '5': case '6': case '7': 132 *cp = (c - '0'); 133 *astate = S_OCTAL2; 134 return (0); 135 case 'M': 136 *cp = (char)0200; 137 *astate = S_META; 138 return (0); 139 case '^': 140 *astate = S_CTRL; 141 return (0); 142 case 'n': 143 *cp = '\n'; 144 *astate = S_GROUND; 145 return (UNVIS_VALID); 146 case 'r': 147 *cp = '\r'; 148 *astate = S_GROUND; 149 return (UNVIS_VALID); 150 case 'b': 151 *cp = '\b'; 152 *astate = S_GROUND; 153 return (UNVIS_VALID); 154 case 'a': 155 *cp = '\007'; 156 *astate = S_GROUND; 157 return (UNVIS_VALID); 158 case 'v': 159 *cp = '\v'; 160 *astate = S_GROUND; 161 return (UNVIS_VALID); 162 case 't': 163 *cp = '\t'; 164 *astate = S_GROUND; 165 return (UNVIS_VALID); 166 case 'f': 167 *cp = '\f'; 168 *astate = S_GROUND; 169 return (UNVIS_VALID); 170 case 's': 171 *cp = ' '; 172 *astate = S_GROUND; 173 return (UNVIS_VALID); 174 case 'E': 175 *cp = '\033'; 176 *astate = S_GROUND; 177 return (UNVIS_VALID); 178 case '\n': 179 /* 180 * hidden newline 181 */ 182 *astate = S_GROUND; 183 return (UNVIS_NOCHAR); 184 case '$': 185 /* 186 * hidden marker 187 */ 188 *astate = S_GROUND; 189 return (UNVIS_NOCHAR); 190 } 191 *astate = S_GROUND; 192 return (UNVIS_SYNBAD); 193 194 case S_META: 195 if (c == '-') 196 *astate = S_META1; 197 else if (c == '^') 198 *astate = S_CTRL; 199 else { 200 *astate = S_GROUND; 201 return (UNVIS_SYNBAD); 202 } 203 return (0); 204 205 case S_META1: 206 *astate = S_GROUND; 207 *cp |= c; 208 return (UNVIS_VALID); 209 210 case S_CTRL: 211 if (c == '?') 212 *cp |= 0177; 213 else 214 *cp |= c & 037; 215 *astate = S_GROUND; 216 return (UNVIS_VALID); 217 218 case S_OCTAL2: /* second possible octal digit */ 219 if (isoctal(c)) { 220 /* 221 * yes - and maybe a third 222 */ 223 *cp = (*cp << 3) + (c - '0'); 224 *astate = S_OCTAL3; 225 return (0); 226 } 227 /* 228 * no - done with current sequence, push back passed char 229 */ 230 *astate = S_GROUND; 231 return (UNVIS_VALIDPUSH); 232 233 case S_OCTAL3: /* third possible octal digit */ 234 *astate = S_GROUND; 235 if (isoctal(c)) { 236 *cp = (*cp << 3) + (c - '0'); 237 return (UNVIS_VALID); 238 } 239 /* 240 * we were done, push back passed char 241 */ 242 return (UNVIS_VALIDPUSH); 243 case S_HEX1: 244 if (isxdigit(c)) { 245 *cp = xtod(c); 246 *astate = S_HEX2; 247 return (0); 248 } 249 /* 250 * no - done with current sequence, push back passed char 251 */ 252 *astate = S_GROUND; 253 return (UNVIS_VALIDPUSH); 254 case S_HEX2: 255 *astate = S_GROUND; 256 if (isxdigit(c)) { 257 *cp = xtod(c) | (*cp << 4); 258 return (UNVIS_VALID); 259 } 260 return (UNVIS_VALIDPUSH); 261 default: 262 /* 263 * decoder in unknown state - (probably uninitialized) 264 */ 265 *astate = S_GROUND; 266 return (UNVIS_SYNBAD); 267 } 268 } 269 270 /* 271 * strunvis - decode src into dst 272 * 273 * Number of chars decoded into dst is returned, -1 on error. 274 * Dst is null terminated. 275 */ 276 277 int 278 strunvisx(dst, src, flag) 279 char *dst; 280 const char *src; 281 int flag; 282 { 283 char c; 284 char *start = dst; 285 int state = 0; 286 287 _DIAGASSERT(src != NULL); 288 _DIAGASSERT(dst != NULL); 289 290 while ((c = *src++) != '\0') { 291 again: 292 switch (__unvis13(dst, c, &state, flag)) { 293 case UNVIS_VALID: 294 dst++; 295 break; 296 case UNVIS_VALIDPUSH: 297 dst++; 298 goto again; 299 case 0: 300 case UNVIS_NOCHAR: 301 break; 302 default: 303 return (-1); 304 } 305 } 306 if (__unvis13(dst, c, &state, UNVIS_END) == UNVIS_VALID) 307 dst++; 308 *dst = '\0'; 309 return (dst - start); 310 } 311 312 int 313 strunvis(dst, src) 314 char *dst; 315 const char *src; 316 { 317 return strunvisx(dst, src, 0); 318 } 319 #endif 320
Indexes created Mon Sep 22 10:09:38 GMT 2025