vis.c revision 1.39
1 /* $NetBSD: vis.c,v 1.39 2009/02/10 23:06:31 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. 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 /*- 33 * Copyright (c) 1999, 2005 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 45 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 46 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 47 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 48 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 49 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 50 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 51 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 52 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 53 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 54 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 55 * POSSIBILITY OF SUCH DAMAGE. 56 */ 57 58 #include <sys/cdefs.h> 59 #if defined(LIBC_SCCS) && !defined(lint) 60 __RCSID("$NetBSD: vis.c,v 1.39 2009/02/10 23:06:31 christos Exp $"); 61 #endif /* LIBC_SCCS and not lint */ 62 63 #include "namespace.h" 64 #include <sys/types.h> 65 66 #include <assert.h> 67 #include <vis.h> 68 #include <stdlib.h> 69 70 #ifdef __weak_alias 71 __weak_alias(strsvis,_strsvis) 72 __weak_alias(strsvisx,_strsvisx) 73 __weak_alias(strvis,_strvis) 74 __weak_alias(strvisx,_strvisx) 75 __weak_alias(svis,_svis) 76 __weak_alias(vis,_vis) 77 #endif 78 79 #if !HAVE_VIS || !HAVE_SVIS 80 #include <ctype.h> 81 #include <limits.h> 82 #include <stdio.h> 83 #include <string.h> 84 85 static char *do_svis(char *, int, int, int, const char *); 86 87 #undef BELL 88 #define BELL '\a' 89 90 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 91 #define iswhite(c) (c == ' ' || c == '\t' || c == '\n') 92 #define issafe(c) (c == '\b' || c == BELL || c == '\r') 93 #define xtoa(c) "0123456789abcdef"[c] 94 #define XTOA(c) "0123456789ABCDEF"[c] 95 96 #define MAXEXTRAS 5 97 98 #define MAKEEXTRALIST(flag, extra, orig_str) \ 99 do { \ 100 const char *orig = orig_str; \ 101 const char *o = orig; \ 102 char *e; \ 103 while (*o++) \ 104 continue; \ 105 extra = malloc((size_t)((o - orig) + MAXEXTRAS)); \ 106 if (!extra) break; \ 107 for (o = orig, e = extra; (*e++ = *o++) != '\0';) \ 108 continue; \ 109 e--; \ 110 if (flag & VIS_SP) *e++ = ' '; \ 111 if (flag & VIS_TAB) *e++ = '\t'; \ 112 if (flag & VIS_NL) *e++ = '\n'; \ 113 if ((flag & VIS_NOSLASH) == 0) *e++ = '\\'; \ 114 *e = '\0'; \ 115 } while (/*CONSTCOND*/0) 116 117 /* 118 * This is do_hvis, for HTTP style (RFC 1808) 119 */ 120 static char * 121 do_hvis(char *dst, int c, int flag, int nextc, const char *extra) 122 { 123 if (!isascii(c) || !isalnum(c) || strchr("$-_.+!*'(),", c) != NULL) { 124 *dst++ = '%'; 125 *dst++ = xtoa(((unsigned int)c >> 4) & 0xf); 126 *dst++ = xtoa((unsigned int)c & 0xf); 127 } else { 128 dst = do_svis(dst, c, flag, nextc, extra); 129 } 130 return dst; 131 } 132 133 /* 134 * This is do_mvis, for Quoted-Printable MIME (RFC 2045) 135 * NB: No handling of long lines or CRLF. 136 */ 137 static char * 138 do_mvis(char *dst, int c, int flag, int nextc, const char *extra) 139 { 140 if ((c != '\n') && 141 /* Space at the end of the line */ 142 ((isspace(c) && (nextc == '\r' || nextc == '\n')) || 143 /* Out of range */ 144 (!isspace(c) && (c < 33 || (c > 60 && c < 62) || c > 126)) || 145 /* Specific char to be escaped */ 146 strchr("#$@[\\]^`{|}~", c) != NULL)) { 147 *dst++ = '='; 148 *dst++ = XTOA(((unsigned int)c >> 4) & 0xf); 149 *dst++ = XTOA((unsigned int)c & 0xf); 150 } else { 151 dst = do_svis(dst, c, flag, nextc, extra); 152 } 153 return dst; 154 } 155 156 /* 157 * This is do_vis, the central code of vis. 158 * dst: Pointer to the destination buffer 159 * c: Character to encode 160 * flag: Flag word 161 * nextc: The character following 'c' 162 * extra: Pointer to the list of extra characters to be 163 * backslash-protected. 164 */ 165 static char * 166 do_svis(char *dst, int c, int flag, int nextc, const char *extra) 167 { 168 int isextra; 169 isextra = strchr(extra, c) != NULL; 170 if (!isextra && isascii(c) && (isgraph(c) || iswhite(c) || 171 ((flag & VIS_SAFE) && issafe(c)))) { 172 *dst++ = c; 173 return dst; 174 } 175 if (flag & VIS_CSTYLE) { 176 switch (c) { 177 case '\n': 178 *dst++ = '\\'; *dst++ = 'n'; 179 return dst; 180 case '\r': 181 *dst++ = '\\'; *dst++ = 'r'; 182 return dst; 183 case '\b': 184 *dst++ = '\\'; *dst++ = 'b'; 185 return dst; 186 case BELL: 187 *dst++ = '\\'; *dst++ = 'a'; 188 return dst; 189 case '\v': 190 *dst++ = '\\'; *dst++ = 'v'; 191 return dst; 192 case '\t': 193 *dst++ = '\\'; *dst++ = 't'; 194 return dst; 195 case '\f': 196 *dst++ = '\\'; *dst++ = 'f'; 197 return dst; 198 case ' ': 199 *dst++ = '\\'; *dst++ = 's'; 200 return dst; 201 case '\0': 202 *dst++ = '\\'; *dst++ = '0'; 203 if (isoctal(nextc)) { 204 *dst++ = '0'; 205 *dst++ = '0'; 206 } 207 return dst; 208 default: 209 if (isgraph(c)) { 210 *dst++ = '\\'; *dst++ = c; 211 return dst; 212 } 213 } 214 } 215 if (isextra || ((c & 0177) == ' ') || (flag & VIS_OCTAL)) { 216 *dst++ = '\\'; 217 *dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + '0'; 218 *dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + '0'; 219 *dst++ = (c & 07) + '0'; 220 } else { 221 if ((flag & VIS_NOSLASH) == 0) *dst++ = '\\'; 222 if (c & 0200) { 223 c &= 0177; *dst++ = 'M'; 224 } 225 if (iscntrl(c)) { 226 *dst++ = '^'; 227 if (c == 0177) 228 *dst++ = '?'; 229 else 230 *dst++ = c + '@'; 231 } else { 232 *dst++ = '-'; *dst++ = c; 233 } 234 } 235 return dst; 236 } 237 238 typedef char *(*visfun_t)(char *, int, int, int, const char *); 239 240 /* 241 * Return the appropriate encoding function depending on the flags given. 242 */ 243 static visfun_t 244 getvisfun(int flag) 245 { 246 if (flag & VIS_HTTPSTYLE) 247 return do_hvis; 248 if (flag * VIS_MIMESTYLE) 249 return do_mvis; 250 return do_svis; 251 } 252 253 /* 254 * svis - visually encode characters, also encoding the characters 255 * pointed to by `extra' 256 */ 257 char * 258 svis(char *dst, int c, int flag, int nextc, const char *extra) 259 { 260 char *nextra = NULL; 261 visfun_t f; 262 263 _DIAGASSERT(dst != NULL); 264 _DIAGASSERT(extra != NULL); 265 MAKEEXTRALIST(flag, nextra, extra); 266 if (!nextra) { 267 *dst = '\0'; /* can't create nextra, return "" */ 268 return dst; 269 } 270 f = getvisfun(flag); 271 dst = (*f)(dst, c, flag, nextc, nextra); 272 free(nextra); 273 *dst = '\0'; 274 return dst; 275 } 276 277 278 /* 279 * strsvis, strsvisx - visually encode characters from src into dst 280 * 281 * Extra is a pointer to a \0-terminated list of characters to 282 * be encoded, too. These functions are useful e. g. to 283 * encode strings in such a way so that they are not interpreted 284 * by a shell. 285 * 286 * Dst must be 4 times the size of src to account for possible 287 * expansion. The length of dst, not including the trailing NULL, 288 * is returned. 289 * 290 * Strsvisx encodes exactly len bytes from src into dst. 291 * This is useful for encoding a block of data. 292 */ 293 int 294 strsvis(char *dst, const char *csrc, int flag, const char *extra) 295 { 296 int c; 297 char *start; 298 char *nextra = NULL; 299 const unsigned char *src = (const unsigned char *)csrc; 300 visfun_t f; 301 302 _DIAGASSERT(dst != NULL); 303 _DIAGASSERT(src != NULL); 304 _DIAGASSERT(extra != NULL); 305 MAKEEXTRALIST(flag, nextra, extra); 306 if (!nextra) { 307 *dst = '\0'; /* can't create nextra, return "" */ 308 return 0; 309 } 310 f = getvisfun(flag); 311 for (start = dst; (c = *src++) != '\0'; /* empty */) 312 dst = (*f)(dst, c, flag, *src, nextra); 313 free(nextra); 314 *dst = '\0'; 315 return (int)(dst - start); 316 } 317 318 319 int 320 strsvisx(char *dst, const char *csrc, size_t len, int flag, const char *extra) 321 { 322 unsigned char c; 323 char *start; 324 char *nextra = NULL; 325 const unsigned char *src = (const unsigned char *)csrc; 326 visfun_t f; 327 328 _DIAGASSERT(dst != NULL); 329 _DIAGASSERT(src != NULL); 330 _DIAGASSERT(extra != NULL); 331 MAKEEXTRALIST(flag, nextra, extra); 332 if (! nextra) { 333 *dst = '\0'; /* can't create nextra, return "" */ 334 return 0; 335 } 336 337 f = getvisfun(flag); 338 for (start = dst; len > 0; len--) { 339 c = *src++; 340 dst = (*f)(dst, c, flag, len > 1 ? *src : '\0', nextra); 341 } 342 free(nextra); 343 *dst = '\0'; 344 return (int)(dst - start); 345 } 346 #endif 347 348 #if !HAVE_VIS 349 /* 350 * vis - visually encode characters 351 */ 352 char * 353 vis(char *dst, int c, int flag, int nextc) 354 { 355 char *extra = NULL; 356 unsigned char uc = (unsigned char)c; 357 visfun_t f; 358 359 _DIAGASSERT(dst != NULL); 360 361 MAKEEXTRALIST(flag, extra, ""); 362 if (! extra) { 363 *dst = '\0'; /* can't create extra, return "" */ 364 return dst; 365 } 366 f = getvisfun(flag); 367 dst = (*f)(dst, uc, flag, nextc, extra); 368 free(extra); 369 *dst = '\0'; 370 return dst; 371 } 372 373 374 /* 375 * strvis, strvisx - visually encode characters from src into dst 376 * 377 * Dst must be 4 times the size of src to account for possible 378 * expansion. The length of dst, not including the trailing NULL, 379 * is returned. 380 * 381 * Strvisx encodes exactly len bytes from src into dst. 382 * This is useful for encoding a block of data. 383 */ 384 int 385 strvis(char *dst, const char *src, int flag) 386 { 387 char *extra = NULL; 388 int rv; 389 390 MAKEEXTRALIST(flag, extra, ""); 391 if (!extra) { 392 *dst = '\0'; /* can't create extra, return "" */ 393 return 0; 394 } 395 rv = strsvis(dst, src, flag, extra); 396 free(extra); 397 return rv; 398 } 399 400 401 int 402 strvisx(char *dst, const char *src, size_t len, int flag) 403 { 404 char *extra = NULL; 405 int rv; 406 407 MAKEEXTRALIST(flag, extra, ""); 408 if (!extra) { 409 *dst = '\0'; /* can't create extra, return "" */ 410 return 0; 411 } 412 rv = strsvisx(dst, src, len, flag, extra); 413 free(extra); 414 return rv; 415 } 416 #endif 417
Indexes created Wed Sep 24 22:09:59 GMT 2025