gen.subproj/vis.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1989, 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * Redistribution and use in source and binary forms, with or without
  27  * modification, are permitted provided that the following conditions
  28  * are met:
  29  * 1. Redistributions of source code must retain the above copyright
  30  *    notice, this list of conditions and the following disclaimer.
  31  * 2. Redistributions in binary form must reproduce the above copyright
  32  *    notice, this list of conditions and the following disclaimer in the
  33  *    documentation and/or other materials provided with the distribution.
  34  * 3. All advertising materials mentioning features or use of this software
  35  *    must display the following acknowledgement:
  36  *      This product includes software developed by the University of
  37  *      California, Berkeley and its contributors.
  38  * 4. Neither the name of the University nor the names of its contributors
  39  *    may be used to endorse or promote products derived from this software
  40  *    without specific prior written permission.
  41  *
  42  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  43  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  44  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  45  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  46  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  47  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  48  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  49  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  50  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  51  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  52  * SUCH DAMAGE.
  53  */
  54
  55
  56 #include <sys/types.h>
  57 #include <limits.h>
  58 #include <ctype.h>
  59 #include <vis.h>
  60
  61 #define isoctal(c)      (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')
  62
  63 /*
  64  * vis - visually encode characters
  65  */
  66 char *
  67 vis(dst, c, flag, nextc)
  68         register char *dst;
  69         int c, nextc;
  70         register int flag;
  71 {
  72         if ((u_int)c <= UCHAR_MAX && isgraph(c) ||
  73            ((flag & VIS_SP) == 0 && c == ' ') ||
  74            ((flag & VIS_TAB) == 0 && c == '\t') ||
  75            ((flag & VIS_NL) == 0 && c == '\n') ||
  76            ((flag & VIS_SAFE) && (c == '\b' || c == '\007' || c == '\r'))) {
  77                 *dst++ = c;
  78                 if (c == '\\' && (flag & VIS_NOSLASH) == 0)
  79                         *dst++ = '\\';
  80                 *dst = '\0';
  81                 return (dst);
  82         }
  83
  84         if (flag & VIS_CSTYLE) {
  85                 switch(c) {
  86                 case '\n':
  87                         *dst++ = '\\';
  88                         *dst++ = 'n';
  89                         goto done;
  90                 case '\r':
  91                         *dst++ = '\\';
  92                         *dst++ = 'r';
  93                         goto done;
  94                 case '\b':
  95                         *dst++ = '\\';
  96                         *dst++ = 'b';
  97                         goto done;
  98 #if __STDC__
  99                 case '\a':
 100 #else
 101                 case '\007':
 102 #endif
 103                         *dst++ = '\\';
 104                         *dst++ = 'a';
 105                         goto done;
 106                 case '\v':
 107                         *dst++ = '\\';
 108                         *dst++ = 'v';
 109                         goto done;
 110                 case '\t':
 111                         *dst++ = '\\';
 112                         *dst++ = 't';
 113                         goto done;
 114                 case '\f':
 115                         *dst++ = '\\';
 116                         *dst++ = 'f';
 117                         goto done;
 118                 case ' ':
 119                         *dst++ = '\\';
 120                         *dst++ = 's';
 121                         goto done;
 122                 case '\0':
 123                         *dst++ = '\\';
 124                         *dst++ = '0';
 125                         if (isoctal(nextc)) {
 126                                 *dst++ = '0';
 127                                 *dst++ = '0';
 128                         }
 129                         goto done;
 130                 }
 131         }
 132         if (((c & 0177) == ' ') || (flag & VIS_OCTAL)) {
 133                 *dst++ = '\\';
 134                 *dst++ = ((u_char)c >> 6 & 07) + '0';
 135                 *dst++ = ((u_char)c >> 3 & 07) + '0';
 136                 *dst++ = ((u_char)c & 07) + '0';
 137                 goto done;
 138         }
 139         if ((flag & VIS_NOSLASH) == 0)
 140                 *dst++ = '\\';
 141         if (c & 0200) {
 142                 c &= 0177;
 143                 *dst++ = 'M';
 144         }
 145         if (iscntrl(c)) {
 146                 *dst++ = '^';
 147                 if (c == 0177)
 148                         *dst++ = '?';
 149                 else
 150                         *dst++ = c + '@';
 151         } else {
 152                 *dst++ = '-';
 153                 *dst++ = c;
 154         }
 155 done:
 156         *dst = '\0';
 157         return (dst);
 158 }
 159
 160 /*
 161  * strvis, strvisx - visually encode characters from src into dst
 162  *
 163  *      Dst must be 4 times the size of src to account for possible
 164  *      expansion.  The length of dst, not including the trailing NULL,
 165  *      is returned.
 166  *
 167  *      Strvisx encodes exactly len bytes from src into dst.
 168  *      This is useful for encoding a block of data.
 169  */
 170 int
 171 strvis(dst, src, flag)
 172         register char *dst;
 173         register const char *src;
 174         int flag;
 175 {
 176         register char c;
 177         char *start;
 178
 179         for (start = dst; c = *src;)
 180                 dst = vis(dst, c, flag, *++src);
 181         *dst = '\0';
 182         return (dst - start);
 183 }
 184
 185 int
 186 strvisx(dst, src, len, flag)
 187         register char *dst;
 188         register const char *src;
 189         register size_t len;
 190         int flag;
 191 {
 192         int c;
 193         char *start;
 194
 195         for (start = dst; len > 1; len--) {
 196                 c = *src;
 197                 dst = vis(dst, c, flag, *++src);
 198         }
 199         if (len)
 200                 dst = vis(dst, *src, flag, '\0');
 201         *dst = '\0';
 202
 203         return (dst - start);
 204 }