1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: src/lib/libc/gen/vis.c,v 1.5.8.2 2001/03/05 09:44:34 obrien Exp $ 34 * $DragonFly: src/lib/libc/gen/vis.c,v 1.3 2004/06/06 15:05:55 hmp Exp $ 35 * 36 * @(#)vis.c 8.1 (Berkeley) 7/19/93 37 */ 38 39 #include <sys/types.h> 40 #include <limits.h> 41 #include <ctype.h> 42 #include <stdio.h> 43 #include <vis.h> 44 45 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 46 47 /* 48 * vis - visually encode characters 49 */ 50 char * 51 vis(dst, c, flag, nextc) 52 char *dst; 53 int c, nextc; 54 int flag; 55 { 56 c = (unsigned char)c; 57 58 if (flag & VIS_HTTPSTYLE) { 59 /* Described in RFC 1808 */ 60 if (!(isalnum(c) /* alpha-numeric */ 61 /* safe */ 62 || c == '$' || c == '-' || c == '_' || c == '.' || c == '+' 63 /* extra */ 64 || c == '!' || c == '*' || c == '\'' || c == '(' 65 || c == ')' || c == ',')) { 66 *dst++ = '%'; 67 snprintf(dst, 4, (c < 16 ? "0%X" : "%X"), c); 68 dst += 2; 69 goto done; 70 } 71 } 72 73 if (isgraph(c) || 74 ((flag & VIS_SP) == 0 && c == ' ') || 75 ((flag & VIS_TAB) == 0 && c == '\t') || 76 ((flag & VIS_NL) == 0 && c == '\n') || 77 ((flag & VIS_SAFE) && (c == '\b' || c == '\007' || c == '\r'))) { 78 *dst++ = c; 79 if (c == '\\' && (flag & VIS_NOSLASH) == 0) 80 *dst++ = '\\'; 81 *dst = '\0'; 82 return (dst); 83 } 84 85 if (flag & VIS_CSTYLE) { 86 switch(c) { 87 case '\n': 88 *dst++ = '\\'; 89 *dst++ = 'n'; 90 goto done; 91 case '\r': 92 *dst++ = '\\'; 93 *dst++ = 'r'; 94 goto done; 95 case '\b': 96 *dst++ = '\\'; 97 *dst++ = 'b'; 98 goto done; 99 #if __STDC__ 100 case '\a': 101 #else 102 case '\007': 103 #endif 104 *dst++ = '\\'; 105 *dst++ = 'a'; 106 goto done; 107 case '\v': 108 *dst++ = '\\'; 109 *dst++ = 'v'; 110 goto done; 111 case '\t': 112 *dst++ = '\\'; 113 *dst++ = 't'; 114 goto done; 115 case '\f': 116 *dst++ = '\\'; 117 *dst++ = 'f'; 118 goto done; 119 case ' ': 120 *dst++ = '\\'; 121 *dst++ = 's'; 122 goto done; 123 case '\0': 124 *dst++ = '\\'; 125 *dst++ = '0'; 126 if (isoctal(nextc)) { 127 *dst++ = '0'; 128 *dst++ = '0'; 129 } 130 goto done; 131 } 132 } 133 if (((c & 0177) == ' ') || (flag & VIS_OCTAL)) { 134 *dst++ = '\\'; 135 *dst++ = ((u_char)c >> 6 & 07) + '0'; 136 *dst++ = ((u_char)c >> 3 & 07) + '0'; 137 *dst++ = ((u_char)c & 07) + '0'; 138 goto done; 139 } 140 if ((flag & VIS_NOSLASH) == 0) 141 *dst++ = '\\'; 142 if (c & 0200) { 143 c &= 0177; 144 *dst++ = 'M'; 145 } 146 if (iscntrl(c)) { 147 *dst++ = '^'; 148 if (c == 0177) 149 *dst++ = '?'; 150 else 151 *dst++ = c + '@'; 152 } else { 153 *dst++ = '-'; 154 *dst++ = c; 155 } 156 done: 157 *dst = '\0'; 158 return (dst); 159 } 160 161 /* 162 * strvis, strvisx - visually encode characters from src into dst 163 * 164 * Dst must be 4 times the size of src to account for possible 165 * expansion. The length of dst, not including the trailing NULL, 166 * is returned. 167 * 168 * Strvisx encodes exactly len bytes from src into dst. 169 * This is useful for encoding a block of data. 170 */ 171 int 172 strvis(dst, src, flag) 173 char *dst; 174 const char *src; 175 int flag; 176 { 177 char c; 178 char *start; 179 180 for (start = dst; (c = *src); ) 181 dst = vis(dst, c, flag, *++src); 182 *dst = '\0'; 183 return (dst - start); 184 } 185 186 int 187 strvisx(dst, src, len, flag) 188 char *dst; 189 const char *src; 190 size_t len; 191 int flag; 192 { 193 int c; 194 char *start; 195 196 for (start = dst; len > 1; len--) { 197 c = *src; 198 dst = vis(dst, c, flag, *++src); 199 } 200 if (len) 201 dst = vis(dst, *src, flag, '\0'); 202 *dst = '\0'; 203 204 return (dst - start); 205 } 206