1 /* $NetBSD: vis.c,v 1.35 2006/08/28 20:42:12 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 * 3. Neither the name of The NetBSD Foundation nor the names of its
45 * contributors may be used to endorse or promote products derived
46 * from this software without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
49 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
50 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
51 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
52 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
53 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
54 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
55 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
56 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
57 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
58 * POSSIBILITY OF SUCH DAMAGE.
59 */
60
61 #include <sys/cdefs.h>
62 __RCSID("$MirOS: src/lib/libc/gen/vis.c,v 1.3 2010/01/07 22:34:50 tg Exp $");
63 __RCSID("$OpenBSD: vis.c,v 1.19 2005/09/01 17:15:49 millert Exp $");
64 __RCSID("$NetBSD: vis.c,v 1.35 2006/08/28 20:42:12 christos Exp $");
65
66 #include <sys/types.h>
67
68 #include <assert.h>
69 #include <vis.h>
70 #include <stdlib.h>
71
72 #include <ctype.h>
73 #include <limits.h>
74 #include <stdio.h>
75 #include <string.h>
76
77 extern const uint8_t mbsd_digits_hex[17];
78
79 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
80 #define iswhite(c) (c == ' ' || c == '\t' || c == '\n')
81 #define issafe(c) (c == '\b' || c == '\a' || c == '\r' || isgraph((u_char)(c)))
82 #define xtoa(c) mbsd_digits_hex[c]
83
84 #define MAXEXTRAS 9
85
86
87 #define MAKEEXTRALIST(flag, extra, orig_str) \
88 do { \
89 const char *orig = orig_str; \
90 const char *o = orig; \
91 char *e; \
92 while (*o++) \
93 continue; \
94 extra = malloc((size_t)((o - orig) + MAXEXTRAS)); \
95 if (!extra) break; \
96 for (o = orig, e = extra; (*e++ = *o++) != '\0';) \
97 continue; \
98 e--; \
99 if (flag & VIS_SP) *e++ = ' '; \
100 if (flag & VIS_TAB) *e++ = '\t'; \
101 if (flag & VIS_NL) *e++ = '\n'; \
102 if ((flag & VIS_NOSLASH) == 0) *e++ = '\\'; \
103 if (flag & VIS_GLOB) { \
104 *e++ = '*'; \
105 *e++ = '?'; \
106 *e++ = '['; \
107 *e++ = '#'; \
108 } \
109 *e = '\0'; \
110 } while (/*CONSTCOND*/0)
111
112
113 /*
114 * This is HVIS, the macro of vis used to HTTP style (RFC 1808)
115 */
116 #define HVIS(dst, c, flag, nextc, extra) \
117 do \
118 if (!isascii(c) || !isalnum(c) || strchr("$-_.+!*'(),", c) != NULL) { \
119 *dst++ = '%'; \
120 *dst++ = xtoa(((unsigned int)c >> 4) & 0xf); \
121 *dst++ = xtoa((unsigned int)c & 0xf); \
122 } else { \
123 SVIS(dst, c, flag, nextc, extra); \
124 } \
125 while (/*CONSTCOND*/0)
126
127 /*
128 * This is SVIS, the central macro of vis.
129 * dst: Pointer to the destination buffer
130 * c: Character to encode
131 * flag: Flag word
132 * nextc: The character following 'c'
133 * extra: Pointer to the list of extra characters to be
134 * backslash-protected.
135 */
136 #define SVIS(dst, c, flag, nextc, extra) \
137 do { \
138 int isextra; \
139 isextra = strchr(extra, c) != NULL; \
140 if (!isextra && isascii(c) && (isgraph(c) || iswhite(c) || \
141 ((flag & VIS_SAFE) && issafe(c)))) { \
142 *dst++ = c; \
143 break; \
144 } \
145 if (flag & VIS_CSTYLE) { \
146 switch (c) { \
147 case '\n': \
148 *dst++ = '\\'; *dst++ = 'n'; \
149 continue; \
150 case '\r': \
151 *dst++ = '\\'; *dst++ = 'r'; \
152 continue; \
153 case '\b': \
154 *dst++ = '\\'; *dst++ = 'b'; \
155 continue; \
156 case '\a': \
157 *dst++ = '\\'; *dst++ = 'a'; \
158 continue; \
159 case '\v': \
160 *dst++ = '\\'; *dst++ = 'v'; \
161 continue; \
162 case '\t': \
163 *dst++ = '\\'; *dst++ = 't'; \
164 continue; \
165 case '\f': \
166 *dst++ = '\\'; *dst++ = 'f'; \
167 continue; \
168 case ' ': \
169 *dst++ = '\\'; *dst++ = 's'; \
170 continue; \
171 case '\0': \
172 *dst++ = '\\'; *dst++ = '0'; \
173 if (isoctal(nextc)) { \
174 *dst++ = '0'; \
175 *dst++ = '0'; \
176 } \
177 continue; \
178 default: \
179 if (isgraph(c)) { \
180 *dst++ = '\\'; *dst++ = c; \
181 continue; \
182 } \
183 } \
184 } \
185 if (isextra || ((c & 0177) == ' ') || (flag & VIS_OCTAL)) { \
186 *dst++ = '\\'; \
187 *dst++ = (u_char)(((u_int32_t)(u_char)c >> 6) & 03) + '0'; \
188 *dst++ = (u_char)(((u_int32_t)(u_char)c >> 3) & 07) + '0'; \
189 *dst++ = (c & 07) + '0'; \
190 } else { \
191 if ((flag & VIS_NOSLASH) == 0) *dst++ = '\\'; \
192 if (c & 0200) { \
193 c &= 0177; *dst++ = 'M'; \
194 } \
195 if (iscntrl(c)) { \
196 *dst++ = '^'; \
197 if (c == 0177) \
198 *dst++ = '?'; \
199 else \
200 *dst++ = c + '@'; \
201 } else { \
202 *dst++ = '-'; *dst++ = c; \
203 } \
204 } \
205 } while (/*CONSTCOND*/0)
206
207
208 /*
209 * svis - visually encode characters, also encoding the characters
210 * pointed to by `extra'
211 */
212 char *
svis(char * dst,int c,int flag,int nextc,const char * extra)213 svis(char *dst, int c, int flag, int nextc, const char *extra)
214 {
215 char *nextra = NULL;
216
217 MAKEEXTRALIST(flag, nextra, extra);
218 if (!nextra) {
219 *dst = '\0'; /* can't create nextra, return "" */
220 return dst;
221 }
222 if (flag & VIS_HTTPSTYLE)
223 HVIS(dst, c, flag, nextc, nextra);
224 else
225 SVIS(dst, c, flag, nextc, nextra);
226 free(nextra);
227 *dst = '\0';
228 return dst;
229 }
230
231
232 /*
233 * strsvis, strnsvis, strsvisx - visually encode characters from src into dst
234 *
235 * Extra is a pointer to a \0-terminated list of characters to
236 * be encoded, too. These functions are useful e. g. to
237 * encode strings in such a way so that they are not interpreted
238 * by a shell.
239 *
240 * Dst must be 4 times the size of src to account for possible
241 * expansion. The length of dst, not including the trailing NUL,
242 * is returned.
243 *
244 * Strsvisx encodes exactly len bytes from src into dst.
245 * This is useful for encoding a block of data.
246 */
247 int
strsvis(char * dst,const char * csrc,int flag,const char * extra)248 strsvis(char *dst, const char *csrc, int flag, const char *extra)
249 {
250 int c;
251 char *start;
252 char *nextra = NULL;
253 const unsigned char *src = (const unsigned char *)csrc;
254
255 MAKEEXTRALIST(flag, nextra, extra);
256 if (!nextra) {
257 *dst = '\0'; /* can't create nextra, return "" */
258 return 0;
259 }
260 if (flag & VIS_HTTPSTYLE) {
261 for (start = dst; (c = *src++) != '\0'; /* empty */)
262 HVIS(dst, c, flag, *src, nextra);
263 } else {
264 for (start = dst; (c = *src++) != '\0'; /* empty */)
265 SVIS(dst, c, flag, *src, nextra);
266 }
267 free(nextra);
268 *dst = '\0';
269 return (dst - start);
270 }
271
272
273 int
strnsvis(char * dst,const char * src,size_t siz,int flag,const char * extra)274 strnsvis(char *dst, const char *src, size_t siz, int flag, const char *extra)
275 {
276 char *start, *end;
277 char tbuf[5];
278 int c, i;
279 char *nextra = NULL;
280
281 MAKEEXTRALIST(flag, nextra, extra);
282 if (!nextra) {
283 *dst = '\0'; /* can't create nextra, return "" */
284 return 0;
285 }
286
287 i = 0;
288 for (start = dst, end = start + siz - 1; (c = *src) && dst < end; ) {
289 /* unoptimised but safe to extend version */
290 i = vis(tbuf, c, flag, *++src) - tbuf;
291 if (dst + i <= end) {
292 memcpy(dst, tbuf, i);
293 dst += i;
294 } else {
295 src--;
296 break;
297 }
298 }
299 if (siz > 0)
300 *dst = '\0';
301 if (dst + i > end) {
302 /* adjust return value for truncation */
303 while ((c = *src))
304 dst += vis(tbuf, c, flag, *++src) - tbuf;
305 }
306 free(nextra);
307 return (dst - start);
308 }
309
310
311 int
strsvisx(char * dst,const char * csrc,size_t len,int flag,const char * extra)312 strsvisx(char *dst, const char *csrc, size_t len, int flag, const char *extra)
313 {
314 unsigned char c;
315 char *start;
316 char *nextra = NULL;
317 const unsigned char *src = (const unsigned char *)csrc;
318
319 MAKEEXTRALIST(flag, nextra, extra);
320 if (! nextra) {
321 *dst = '\0'; /* can't create nextra, return "" */
322 return 0;
323 }
324
325 if (flag & VIS_HTTPSTYLE) {
326 for (start = dst; len > 0; len--) {
327 c = *src++;
328 HVIS(dst, c, flag, len ? *src : '\0', nextra);
329 }
330 } else {
331 for (start = dst; len > 0; len--) {
332 c = *src++;
333 SVIS(dst, c, flag, len ? *src : '\0', nextra);
334 }
335 }
336 free(nextra);
337 *dst = '\0';
338 return (dst - start);
339 }
340
341 /*
342 * vis - visually encode characters
343 */
344 char *
vis(char * dst,int c,int flag,int nextc)345 vis(char *dst, int c, int flag, int nextc)
346 {
347 char *extra = NULL;
348 unsigned char uc = (unsigned char)c;
349
350 MAKEEXTRALIST(flag, extra, "");
351 if (! extra) {
352 *dst = '\0'; /* can't create extra, return "" */
353 return dst;
354 }
355 if (flag & VIS_HTTPSTYLE)
356 HVIS(dst, uc, flag, nextc, extra);
357 else
358 SVIS(dst, uc, flag, nextc, extra);
359 free(extra);
360 *dst = '\0';
361 return dst;
362 }
363
364
365 /*
366 * strvis, strnvis, strvisx - visually encode characters from src into dst
367 *
368 * Dst must be 4 times the size of src to account for possible
369 * expansion. The length of dst, not including the trailing NUL,
370 * is returned.
371 *
372 * Strnvis will write no more than siz-1 bytes (and will NUL terminate).
373 * The number of bytes needed to fully encode the string is returned.
374 *
375 * Strvisx encodes exactly len bytes from src into dst.
376 * This is useful for encoding a block of data.
377 */
378 int
strvis(char * dst,const char * src,int flag)379 strvis(char *dst, const char *src, int flag)
380 {
381 char *extra = NULL;
382 int rv;
383
384 MAKEEXTRALIST(flag, extra, "");
385 if (!extra) {
386 *dst = '\0'; /* can't create extra, return "" */
387 return 0;
388 }
389 rv = strsvis(dst, src, flag, extra);
390 free(extra);
391 return rv;
392 }
393
394
395 int
strnvis(char * dst,const char * src,size_t siz,int flag)396 strnvis(char *dst, const char *src, size_t siz, int flag)
397 {
398 char *extra = NULL;
399 int rv;
400
401 MAKEEXTRALIST(flag, extra, "");
402 if (!extra) {
403 *dst = '\0'; /* can't create extra, return "" */
404 return 0;
405 }
406 rv = strnsvis(dst, src, siz, flag, extra);
407 free(extra);
408 return rv;
409 }
410
411
412 int
strvisx(char * dst,const char * src,size_t len,int flag)413 strvisx(char *dst, const char *src, size_t len, int flag)
414 {
415 char *extra = NULL;
416 int rv;
417
418 MAKEEXTRALIST(flag, extra, "");
419 if (!extra) {
420 *dst = '\0'; /* can't create extra, return "" */
421 return 0;
422 }
423 rv = strsvisx(dst, src, len, flag, extra);
424 free(extra);
425 return rv;
426 }
427