lib/libc/gen/shquote.c

   1 /* $NetBSD: shquote.c,v 1.8 2006/03/19 02:33:02 christos Exp $ */
   2
   3 /*
   4  * Copyright (c) 2001 Christopher G. Demetriou
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *          This product includes software developed for the
  18  *          NetBSD Project.  See http://www.NetBSD.org/ for
  19  *          information about NetBSD.
  20  * 4. The name of the author may not be used to endorse or promote products
  21  *    derived from this software without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  *
  34  * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
  35  */
  36
  37 #include <sys/cdefs.h>
  38 #if defined(LIBC_SCCS) && !defined(lint)
  39 __RCSID("$NetBSD: shquote.c,v 1.8 2006/03/19 02:33:02 christos Exp $");
  40 #endif /* LIBC_SCCS and not lint */
  41
  42 /*
  43  * Define SHQUOTE_USE_MULTIBYTE if you want shquote() to handle multibyte
  44  * characters using mbrtowc().
  45  *
  46  * Please DO NOT rip this #ifdef out of the code.  It's also here to help
  47  * portability.
  48  */
  49 #undef  SHQUOTE_USE_MULTIBYTE
  50
  51 #include "namespace.h"
  52 #include <stdlib.h>
  53 #include <string.h>
  54 #ifdef SHQUOTE_USE_MULTIBYTE
  55 #include <limits.h>
  56 #include <stdio.h>
  57 #include <wchar.h>
  58 #endif
  59
  60 #ifdef __weak_alias
  61 __weak_alias(shquote,_shquote)
  62 #endif
  63
  64 /*
  65  * shquote():
  66  *
  67  * Requotes arguments so that they'll be interpreted properly by the
  68  * shell (/bin/sh).
  69  *
  70  * Wraps single quotes around the string, and replaces single quotes
  71  * in the string with the sequence:
  72  *      '\''
  73  *
  74  * Returns the number of characters required to hold the resulting quoted
  75  * argument.
  76  *
  77  * The buffer supplied is filled in and NUL-terminated.  If 'bufsize'
  78  * indicates that the buffer is too short to hold the output string, the
  79  * first (bufsize - 1) bytes of quoted argument are filled in and the
  80  * buffer is NUL-terminated.
  81  *
  82  * Changes could be made to optimize the length of strings output by this
  83  * function:
  84  *
  85  *      * if there are no metacharacters or whitespace in the input,
  86  *        the output could be the input string.
  87  */
  88
  89 #ifdef SHQUOTE_USE_MULTIBYTE
  90
  91 #define XLATE_OUTCH(x)          wcrtomb(outch, (x), &mbso)
  92 #define XLATE_INCH()                                            \
  93     do {                                                        \
  94         n = mbrtowc(&c, arg, MB_CUR_MAX, &mbsi);                \
  95     } while (/*LINTED const cond*/0)
  96
  97 #else
  98
  99 #define XLATE_OUTCH(x)          (outch[0] = (x), 1)
 100 #define XLATE_INCH()                                            \
 101     do {                                                        \
 102         n = ((c = *arg) != '\0') ? 1 : 0;                       \
 103     } while (/*LINTED const cond*/0)
 104
 105 #endif
 106
 107 #define PUT(x)                                                  \
 108     do {                                                        \
 109         outchlen = XLATE_OUTCH(x);                              \
 110         if (outchlen == (size_t)-1)                             \
 111                 goto bad;                                       \
 112         rv += outchlen;                                         \
 113         if (bufsize != 0) {                                     \
 114                 if (bufsize < outchlen ||                       \
 115                     (bufsize == outchlen &&                     \
 116                      outch[outchlen - 1] != '\0')) {            \
 117                         *buf = '\0';                            \
 118                         bufsize = 0;                            \
 119                 } else {                                        \
 120                         memcpy(buf, outch, outchlen);           \
 121                         buf += outchlen;                        \
 122                         bufsize -= outchlen;                    \
 123                 }                                               \
 124         }                                                       \
 125     } while (/*LINTED const cond*/0)
 126
 127 size_t
 128 shquote(const char *arg, char *buf, size_t bufsize)
 129 {
 130 #ifdef SHQUOTE_USE_MULTIBYTE
 131         char outch[MB_LEN_MAX];
 132         mbstate_t mbsi, mbso;
 133         wchar_t c, lastc;
 134         size_t outchlen;
 135 #else
 136         char outch[1];
 137         char c, lastc;
 138         size_t outchlen;
 139 #endif
 140         size_t rv;
 141         int n;
 142
 143         rv = 0;
 144         lastc = 0;
 145 #ifdef SHQUOTE_USE_MULTIBYTE
 146         memset(&mbsi, 0, sizeof mbsi);
 147         memset(&mbso, 0, sizeof mbso);
 148 #endif
 149
 150         if (*arg != '\'')
 151                 PUT('\'');
 152         for (;;) {
 153                 XLATE_INCH();
 154                 if (n <= 0)
 155                         break;
 156                 arg += n;
 157                 lastc = c;
 158
 159                 if (c == '\'') {
 160                         if (rv != 0)
 161                                 PUT('\'');
 162                         PUT('\\');
 163                         PUT('\'');
 164                         for (;;) {
 165                                 XLATE_INCH();
 166                                 if (n <= 0 || c != '\'')
 167                                         break;
 168                                 PUT('\\');
 169                                 PUT('\'');
 170                                 arg += n;
 171                         }
 172                         if (n > 0)
 173                                 PUT('\'');
 174                 } else
 175                         PUT(c);
 176         }
 177         if (lastc != '\'')
 178                 PUT('\'');
 179
 180         /* Put multibyte or NUL terminator, but don't count the NUL. */
 181         PUT('\0');
 182         rv--;
 183
 184         return rv;
 185
 186 bad:
 187         /* A multibyte character encoding or decoding error occurred. */
 188         return (size_t)-1;
 189 }