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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD: src/lib/libc/gen/vis.c,v 1.13 2003/10/30 12:41:50 phk Exp $ 30 * $DragonFly: src/lib/libc/gen/vis.c,v 1.6 2005/11/13 00:07:42 swildner Exp $ 31 */ 32 33 #include <sys/types.h> 34 #include <ctype.h> 35 #include <limits.h> 36 #include <stdio.h> 37 #include <string.h> 38 #include <vis.h> 39 40 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 41 42 /* 43 * vis - visually encode characters 44 */ 45 char * 46 vis(char *dst, int c, int flag, int nextc) 47 { 48 c = (unsigned char)c; 49 50 if (flag & VIS_HTTPSTYLE) { 51 /* Described in RFC 1808 */ 52 if (!(isalnum(c) /* alpha-numeric */ 53 /* safe */ 54 || c == '$' || c == '-' || c == '_' || c == '.' || c == '+' 55 /* extra */ 56 || c == '!' || c == '*' || c == '\'' || c == '(' 57 || c == ')' || c == ',')) { 58 *dst++ = '%'; 59 snprintf(dst, 4, (c < 16 ? "0%X" : "%X"), c); 60 dst += 2; 61 goto done; 62 } 63 } 64 65 if ((flag & VIS_GLOB) && 66 (c == '*' || c == '?' || c == '[' || c == '#')) 67 ; 68 else if (isgraph(c) || 69 ((flag & VIS_SP) == 0 && c == ' ') || 70 ((flag & VIS_TAB) == 0 && c == '\t') || 71 ((flag & VIS_NL) == 0 && c == '\n') || 72 ((flag & VIS_SAFE) && (c == '\b' || c == '\007' || c == '\r'))) { 73 *dst++ = c; 74 if (c == '\\' && (flag & VIS_NOSLASH) == 0) 75 *dst++ = '\\'; 76 *dst = '\0'; 77 return (dst); 78 } 79 80 if (flag & VIS_CSTYLE) { 81 switch(c) { 82 case '\n': 83 *dst++ = '\\'; 84 *dst++ = 'n'; 85 goto done; 86 case '\r': 87 *dst++ = '\\'; 88 *dst++ = 'r'; 89 goto done; 90 case '\b': 91 *dst++ = '\\'; 92 *dst++ = 'b'; 93 goto done; 94 case '\a': 95 *dst++ = '\\'; 96 *dst++ = 'a'; 97 goto done; 98 case '\v': 99 *dst++ = '\\'; 100 *dst++ = 'v'; 101 goto done; 102 case '\t': 103 *dst++ = '\\'; 104 *dst++ = 't'; 105 goto done; 106 case '\f': 107 *dst++ = '\\'; 108 *dst++ = 'f'; 109 goto done; 110 case ' ': 111 *dst++ = '\\'; 112 *dst++ = 's'; 113 goto done; 114 case '\0': 115 *dst++ = '\\'; 116 *dst++ = '0'; 117 if (isoctal(nextc)) { 118 *dst++ = '0'; 119 *dst++ = '0'; 120 } 121 goto done; 122 } 123 } 124 if (((c & 0177) == ' ') || isgraph(c) || (flag & VIS_OCTAL)) { 125 *dst++ = '\\'; 126 *dst++ = ((u_char)c >> 6 & 07) + '0'; 127 *dst++ = ((u_char)c >> 3 & 07) + '0'; 128 *dst++ = ((u_char)c & 07) + '0'; 129 goto done; 130 } 131 if ((flag & VIS_NOSLASH) == 0) 132 *dst++ = '\\'; 133 if (c & 0200) { 134 c &= 0177; 135 *dst++ = 'M'; 136 } 137 if (iscntrl(c)) { 138 *dst++ = '^'; 139 if (c == 0177) 140 *dst++ = '?'; 141 else 142 *dst++ = c + '@'; 143 } else { 144 *dst++ = '-'; 145 *dst++ = c; 146 } 147 done: 148 *dst = '\0'; 149 return (dst); 150 } 151 152 /* 153 * strvis, strvisx - visually encode characters from src into dst 154 * 155 * Dst must be 4 times the size of src to account for possible 156 * expansion. The length of dst, not including the trailing NUL, 157 * is returned. 158 * 159 * Strvisx encodes exactly len bytes from src into dst. 160 * This is useful for encoding a block of data. 161 */ 162 int 163 strvis(char *dst, const char *src, int flag) 164 { 165 char c; 166 char *start; 167 168 for (start = dst; (c = *src); ) 169 dst = vis(dst, c, flag, *++src); 170 *dst = '\0'; 171 return (dst - start); 172 } 173 174 int 175 strnvis(char *dst, const char *src, size_t len, int flag) 176 { 177 char *start, *end; 178 char buf[5]; 179 int c, i; 180 181 i = 0; 182 start = dst; 183 end = start + len -1; 184 for (; (c = *src) != '\0';) { 185 i = vis(buf, c, flag, *++src) - buf; 186 if (start + i > end) { 187 --src; 188 break; 189 } 190 memcpy(dst, buf, i); 191 dst += i; 192 } 193 if (len > 0) 194 *dst = '\0'; 195 if (dst + i > end) { 196 /* adjust return value for truncation */ 197 while ((c = *src) != '\0') 198 dst += vis(buf, c, flag, *++src) - buf; 199 } 200 return (dst - start); 201 } 202 203 int 204 strvisx(char *dst, const char *src, size_t len, int flag) 205 { 206 int c; 207 char *start; 208 209 for (start = dst; len > 1; len--) { 210 c = *src; 211 dst = vis(dst, c, flag, *++src); 212 } 213 if (len) 214 dst = vis(dst, *src, flag, '\0'); 215 *dst = '\0'; 216 217 return (dst - start); 218 } 219