1 /* $NetBSD: vis.c,v 1.36 2008/04/29 06:53:01 martin 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 1.36 2008/04/29 06:53:01 martin Exp $"); 61 #endif /* LIBC_SCCS and not lint */ 62 63 #include "namespace.h" 64 #include <sys/types.h> 65 66 #include <assert.h> 67 #include <vis.h> 68 #include <stdlib.h> 69 70 #ifdef __weak_alias 71 __weak_alias(strsvis,_strsvis) 72 __weak_alias(strsvisx,_strsvisx) 73 __weak_alias(strvis,_strvis) 74 __weak_alias(strvisx,_strvisx) 75 __weak_alias(svis,_svis) 76 __weak_alias(vis,_vis) 77 #endif 78 79 #if !HAVE_VIS || !HAVE_SVIS 80 #include <ctype.h> 81 #include <limits.h> 82 #include <stdio.h> 83 #include <string.h> 84 85 #undef BELL 86 #define BELL '\a' 87 88 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 89 #define iswhite(c) (c == ' ' || c == '\t' || c == '\n') 90 #define issafe(c) (c == '\b' || c == BELL || c == '\r') 91 #define xtoa(c) "0123456789abcdef"[c] 92 93 #define MAXEXTRAS 5 94 95 96 #define MAKEEXTRALIST(flag, extra, orig_str) \ 97 do { \ 98 const char *orig = orig_str; \ 99 const char *o = orig; \ 100 char *e; \ 101 while (*o++) \ 102 continue; \ 103 extra = malloc((size_t)((o - orig) + MAXEXTRAS)); \ 104 if (!extra) break; \ 105 for (o = orig, e = extra; (*e++ = *o++) != '\0';) \ 106 continue; \ 107 e--; \ 108 if (flag & VIS_SP) *e++ = ' '; \ 109 if (flag & VIS_TAB) *e++ = '\t'; \ 110 if (flag & VIS_NL) *e++ = '\n'; \ 111 if ((flag & VIS_NOSLASH) == 0) *e++ = '\\'; \ 112 *e = '\0'; \ 113 } while (/*CONSTCOND*/0) 114 115 116 /* 117 * This is HVIS, the macro of vis used to HTTP style (RFC 1808) 118 */ 119 #define HVIS(dst, c, flag, nextc, extra) \ 120 do \ 121 if (!isascii(c) || !isalnum(c) || strchr("$-_.+!*'(),", c) != NULL) { \ 122 *dst++ = '%'; \ 123 *dst++ = xtoa(((unsigned int)c >> 4) & 0xf); \ 124 *dst++ = xtoa((unsigned int)c & 0xf); \ 125 } else { \ 126 SVIS(dst, c, flag, nextc, extra); \ 127 } \ 128 while (/*CONSTCOND*/0) 129 130 /* 131 * This is SVIS, the central macro of vis. 132 * dst: Pointer to the destination buffer 133 * c: Character to encode 134 * flag: Flag word 135 * nextc: The character following 'c' 136 * extra: Pointer to the list of extra characters to be 137 * backslash-protected. 138 */ 139 #define SVIS(dst, c, flag, nextc, extra) \ 140 do { \ 141 int isextra; \ 142 isextra = strchr(extra, c) != NULL; \ 143 if (!isextra && isascii(c) && (isgraph(c) || iswhite(c) || \ 144 ((flag & VIS_SAFE) && issafe(c)))) { \ 145 *dst++ = c; \ 146 break; \ 147 } \ 148 if (flag & VIS_CSTYLE) { \ 149 switch (c) { \ 150 case '\n': \ 151 *dst++ = '\\'; *dst++ = 'n'; \ 152 continue; \ 153 case '\r': \ 154 *dst++ = '\\'; *dst++ = 'r'; \ 155 continue; \ 156 case '\b': \ 157 *dst++ = '\\'; *dst++ = 'b'; \ 158 continue; \ 159 case BELL: \ 160 *dst++ = '\\'; *dst++ = 'a'; \ 161 continue; \ 162 case '\v': \ 163 *dst++ = '\\'; *dst++ = 'v'; \ 164 continue; \ 165 case '\t': \ 166 *dst++ = '\\'; *dst++ = 't'; \ 167 continue; \ 168 case '\f': \ 169 *dst++ = '\\'; *dst++ = 'f'; \ 170 continue; \ 171 case ' ': \ 172 *dst++ = '\\'; *dst++ = 's'; \ 173 continue; \ 174 case '\0': \ 175 *dst++ = '\\'; *dst++ = '0'; \ 176 if (isoctal(nextc)) { \ 177 *dst++ = '0'; \ 178 *dst++ = '0'; \ 179 } \ 180 continue; \ 181 default: \ 182 if (isgraph(c)) { \ 183 *dst++ = '\\'; *dst++ = c; \ 184 continue; \ 185 } \ 186 } \ 187 } \ 188 if (isextra || ((c & 0177) == ' ') || (flag & VIS_OCTAL)) { \ 189 *dst++ = '\\'; \ 190 *dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + '0'; \ 191 *dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + '0'; \ 192 *dst++ = (c & 07) + '0'; \ 193 } else { \ 194 if ((flag & VIS_NOSLASH) == 0) *dst++ = '\\'; \ 195 if (c & 0200) { \ 196 c &= 0177; *dst++ = 'M'; \ 197 } \ 198 if (iscntrl(c)) { \ 199 *dst++ = '^'; \ 200 if (c == 0177) \ 201 *dst++ = '?'; \ 202 else \ 203 *dst++ = c + '@'; \ 204 } else { \ 205 *dst++ = '-'; *dst++ = c; \ 206 } \ 207 } \ 208 } while (/*CONSTCOND*/0) 209 210 211 /* 212 * svis - visually encode characters, also encoding the characters 213 * pointed to by `extra' 214 */ 215 char * 216 svis(char *dst, int c, int flag, int nextc, const char *extra) 217 { 218 char *nextra = NULL; 219 220 _DIAGASSERT(dst != NULL); 221 _DIAGASSERT(extra != NULL); 222 MAKEEXTRALIST(flag, nextra, extra); 223 if (!nextra) { 224 *dst = '\0'; /* can't create nextra, return "" */ 225 return dst; 226 } 227 if (flag & VIS_HTTPSTYLE) 228 HVIS(dst, c, flag, nextc, nextra); 229 else 230 SVIS(dst, c, flag, nextc, nextra); 231 free(nextra); 232 *dst = '\0'; 233 return dst; 234 } 235 236 237 /* 238 * strsvis, strsvisx - visually encode characters from src into dst 239 * 240 * Extra is a pointer to a \0-terminated list of characters to 241 * be encoded, too. These functions are useful e. g. to 242 * encode strings in such a way so that they are not interpreted 243 * by a shell. 244 * 245 * Dst must be 4 times the size of src to account for possible 246 * expansion. The length of dst, not including the trailing NULL, 247 * is returned. 248 * 249 * Strsvisx encodes exactly len bytes from src into dst. 250 * This is useful for encoding a block of data. 251 */ 252 int 253 strsvis(char *dst, const char *csrc, int flag, const char *extra) 254 { 255 int c; 256 char *start; 257 char *nextra = NULL; 258 const unsigned char *src = (const unsigned char *)csrc; 259 260 _DIAGASSERT(dst != NULL); 261 _DIAGASSERT(src != NULL); 262 _DIAGASSERT(extra != NULL); 263 MAKEEXTRALIST(flag, nextra, extra); 264 if (!nextra) { 265 *dst = '\0'; /* can't create nextra, return "" */ 266 return 0; 267 } 268 if (flag & VIS_HTTPSTYLE) { 269 for (start = dst; (c = *src++) != '\0'; /* empty */) 270 HVIS(dst, c, flag, *src, nextra); 271 } else { 272 for (start = dst; (c = *src++) != '\0'; /* empty */) 273 SVIS(dst, c, flag, *src, nextra); 274 } 275 free(nextra); 276 *dst = '\0'; 277 return (dst - start); 278 } 279 280 281 int 282 strsvisx(char *dst, const char *csrc, size_t len, int flag, const char *extra) 283 { 284 unsigned char c; 285 char *start; 286 char *nextra = NULL; 287 const unsigned char *src = (const unsigned char *)csrc; 288 289 _DIAGASSERT(dst != NULL); 290 _DIAGASSERT(src != NULL); 291 _DIAGASSERT(extra != NULL); 292 MAKEEXTRALIST(flag, nextra, extra); 293 if (! nextra) { 294 *dst = '\0'; /* can't create nextra, return "" */ 295 return 0; 296 } 297 298 if (flag & VIS_HTTPSTYLE) { 299 for (start = dst; len > 0; len--) { 300 c = *src++; 301 HVIS(dst, c, flag, len ? *src : '\0', nextra); 302 } 303 } else { 304 for (start = dst; len > 0; len--) { 305 c = *src++; 306 SVIS(dst, c, flag, len ? *src : '\0', nextra); 307 } 308 } 309 free(nextra); 310 *dst = '\0'; 311 return (dst - start); 312 } 313 #endif 314 315 #if !HAVE_VIS 316 /* 317 * vis - visually encode characters 318 */ 319 char * 320 vis(char *dst, int c, int flag, int nextc) 321 { 322 char *extra = NULL; 323 unsigned char uc = (unsigned char)c; 324 325 _DIAGASSERT(dst != NULL); 326 327 MAKEEXTRALIST(flag, extra, ""); 328 if (! extra) { 329 *dst = '\0'; /* can't create extra, return "" */ 330 return dst; 331 } 332 if (flag & VIS_HTTPSTYLE) 333 HVIS(dst, uc, flag, nextc, extra); 334 else 335 SVIS(dst, uc, flag, nextc, extra); 336 free(extra); 337 *dst = '\0'; 338 return dst; 339 } 340 341 342 /* 343 * strvis, strvisx - visually encode characters from src into dst 344 * 345 * Dst must be 4 times the size of src to account for possible 346 * expansion. The length of dst, not including the trailing NULL, 347 * is returned. 348 * 349 * Strvisx encodes exactly len bytes from src into dst. 350 * This is useful for encoding a block of data. 351 */ 352 int 353 strvis(char *dst, const char *src, int flag) 354 { 355 char *extra = NULL; 356 int rv; 357 358 MAKEEXTRALIST(flag, extra, ""); 359 if (!extra) { 360 *dst = '\0'; /* can't create extra, return "" */ 361 return 0; 362 } 363 rv = strsvis(dst, src, flag, extra); 364 free(extra); 365 return rv; 366 } 367 368 369 int 370 strvisx(char *dst, const char *src, size_t len, int flag) 371 { 372 char *extra = NULL; 373 int rv; 374 375 MAKEEXTRALIST(flag, extra, ""); 376 if (!extra) { 377 *dst = '\0'; /* can't create extra, return "" */ 378 return 0; 379 } 380 rv = strsvisx(dst, src, len, flag, extra); 381 free(extra); 382 return rv; 383 } 384 #endif 385