1 /* $OpenBSD: vis.c,v 1.25 2015/09/13 11:32:51 guenther Exp $ */
3 * Copyright (c) 1989, 1993
4 * The Regents of the University of California. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 #include <sys/types.h>
40 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
41 #define isvisible(c,flag) \
42 (((c) == '\\' || (flag & VIS_ALL) == 0) && \
43 (((u_int)(c) <= UCHAR_MAX && isascii((u_char)(c)) && \
44 (((c) != '*' && (c) != '?' && (c) != '[' && (c) != '#') || \
45 (flag & VIS_GLOB) == 0) && isgraph((u_char)(c))) || \
46 ((flag & VIS_SP) == 0 && (c) == ' ') || \
47 ((flag & VIS_TAB) == 0 && (c) == '\t') || \
48 ((flag & VIS_NL) == 0 && (c) == '\n') || \
49 ((flag & VIS_SAFE) && ((c) == '\b' || \
50 (c) == '\007' || (c) == '\r' || \
51 isgraph((u_char)(c))))))
54 * vis - visually encode characters
57 vis(char *dst, int c, int flag, int nextc)
59 if (isvisible(c, flag)) {
60 if ((c == '"' && (flag & VIS_DQ) != 0) ||
61 (c == '\\' && (flag & VIS_NOSLASH) == 0))
68 if (flag & VIS_CSTYLE) {
105 if (isoctal(nextc)) {
112 if (((c & 0177) == ' ') || (flag & VIS_OCTAL) ||
113 ((flag & VIS_GLOB) && (c == '*' || c == '?' || c == '[' || c == '#'))) {
115 *dst++ = ((u_char)c >> 6 & 07) + '0';
116 *dst++ = ((u_char)c >> 3 & 07) + '0';
117 *dst++ = ((u_char)c & 07) + '0';
120 if ((flag & VIS_NOSLASH) == 0)
126 if (iscntrl((u_char)c)) {
142 * strvis, strnvis, strvisx - visually encode characters from src into dst
144 * Dst must be 4 times the size of src to account for possible
145 * expansion. The length of dst, not including the trailing NULL,
148 * Strnvis will write no more than siz-1 bytes (and will NULL terminate).
149 * The number of bytes needed to fully encode the string is returned.
151 * Strvisx encodes exactly len bytes from src into dst.
152 * This is useful for encoding a block of data.
155 strvis(char *dst, const char *src, int flag)
160 for (start = dst; (c = *src);)
161 dst = vis(dst, c, flag, *++src);
163 return (dst - start);
167 strnvis(char *dst, const char *src, size_t siz, int flag)
174 for (start = dst, end = start + siz - 1; (c = *src) && dst < end; ) {
175 if (isvisible(c, flag)) {
176 if ((c == '"' && (flag & VIS_DQ) != 0) ||
177 (c == '\\' && (flag & VIS_NOSLASH) == 0)) {
178 /* need space for the extra '\\' */
179 if (dst + 1 >= end) {
189 i = vis(tbuf, c, flag, *++src) - tbuf;
190 if (dst + i <= end) {
191 memcpy(dst, tbuf, i);
202 /* adjust return value for truncation */
204 dst += vis(tbuf, c, flag, *++src) - tbuf;
206 return (dst - start);
210 stravis(char **outp, const char *src, int flag)
215 buf = reallocarray(NULL, 4, strlen(src) + 1);
218 len = strvis(buf, src, flag);
220 *outp = realloc(buf, len + 1);
229 strvisx(char *dst, const char *src, size_t len, int flag)
234 for (start = dst; len > 1; len--) {
236 dst = vis(dst, c, flag, *++src);
239 dst = vis(dst, *src, flag, '\0');
241 return (dst - start);