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 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char rcsid[] = "$OpenBSD: vis.c,v 1.4 1997/07/25 20:30:05 mickey Exp $"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/types.h> 39 #include <limits.h> 40 #include <ctype.h> 41 #include <vis.h> 42 43 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 44 45 /* 46 * vis - visually encode characters 47 */ 48 char * 49 vis(dst, c, flag, nextc) 50 register char *dst; 51 int c, nextc; 52 register int flag; 53 { 54 if (((u_int)c <= UCHAR_MAX && isascii(c) && isgraph(c)) || 55 ((flag & VIS_SP) == 0 && c == ' ') || 56 ((flag & VIS_TAB) == 0 && c == '\t') || 57 ((flag & VIS_NL) == 0 && c == '\n') || 58 ((flag & VIS_SAFE) && (c == '\b' || c == '\007' || c == '\r'))) { 59 *dst++ = c; 60 if (c == '\\' && (flag & VIS_NOSLASH) == 0) 61 *dst++ = '\\'; 62 *dst = '\0'; 63 return (dst); 64 } 65 66 if (flag & VIS_CSTYLE) { 67 switch(c) { 68 case '\n': 69 *dst++ = '\\'; 70 *dst++ = 'n'; 71 goto done; 72 case '\r': 73 *dst++ = '\\'; 74 *dst++ = 'r'; 75 goto done; 76 case '\b': 77 *dst++ = '\\'; 78 *dst++ = 'b'; 79 goto done; 80 #ifdef __STDC__ 81 case '\a': 82 #else 83 case '\007': 84 #endif 85 *dst++ = '\\'; 86 *dst++ = 'a'; 87 goto done; 88 case '\v': 89 *dst++ = '\\'; 90 *dst++ = 'v'; 91 goto done; 92 case '\t': 93 *dst++ = '\\'; 94 *dst++ = 't'; 95 goto done; 96 case '\f': 97 *dst++ = '\\'; 98 *dst++ = 'f'; 99 goto done; 100 case ' ': 101 *dst++ = '\\'; 102 *dst++ = 's'; 103 goto done; 104 case '\0': 105 *dst++ = '\\'; 106 *dst++ = '0'; 107 if (isoctal(nextc)) { 108 *dst++ = '0'; 109 *dst++ = '0'; 110 } 111 goto done; 112 } 113 } 114 if (((c & 0177) == ' ') || (flag & VIS_OCTAL)) { 115 *dst++ = '\\'; 116 *dst++ = ((u_char)c >> 6 & 07) + '0'; 117 *dst++ = ((u_char)c >> 3 & 07) + '0'; 118 *dst++ = ((u_char)c & 07) + '0'; 119 goto done; 120 } 121 if ((flag & VIS_NOSLASH) == 0) 122 *dst++ = '\\'; 123 if (c & 0200) { 124 c &= 0177; 125 *dst++ = 'M'; 126 } 127 if (iscntrl(c)) { 128 *dst++ = '^'; 129 if (c == 0177) 130 *dst++ = '?'; 131 else 132 *dst++ = c + '@'; 133 } else { 134 *dst++ = '-'; 135 *dst++ = c; 136 } 137 done: 138 *dst = '\0'; 139 return (dst); 140 } 141 142 /* 143 * strvis, strvisx - visually encode characters from src into dst 144 * 145 * Dst must be 4 times the size of src to account for possible 146 * expansion. The length of dst, not including the trailing NULL, 147 * is returned. 148 * 149 * Strvisx encodes exactly len bytes from src into dst. 150 * This is useful for encoding a block of data. 151 */ 152 int 153 strvis(dst, src, flag) 154 register char *dst; 155 register const char *src; 156 int flag; 157 { 158 register char c; 159 char *start; 160 161 for (start = dst; (c = *src);) 162 dst = vis(dst, c, flag, *++src); 163 *dst = '\0'; 164 return (dst - start); 165 } 166 167 int 168 strvisx(dst, src, len, flag) 169 register char *dst; 170 register const char *src; 171 register size_t len; 172 int flag; 173 { 174 register char c; 175 char *start; 176 177 for (start = dst; len > 1; len--) { 178 c = *src; 179 dst = vis(dst, c, flag, *++src); 180 } 181 if (len) 182 dst = vis(dst, *src, flag, '\0'); 183 *dst = '\0'; 184 185 return (dst - start); 186 } 187