The Tcpdump Group git mirrors - libpcap/blob - portability.h

   1 /*
   2  * Copyright (c) 1994, 1995, 1996
   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 Computer Systems
  16  *      Engineering Group at Lawrence Berkeley Laboratory.
  17  * 4. Neither the name of the University nor of the Laboratory may be used
  18  *    to endorse or promote products derived from this software without
  19  *    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 #ifndef portability_h
  35 #define portability_h
  36
  37 /*
  38  * Helpers for portability between Windows and UN*X and between different
  39  * flavors of UN*X.
  40  */
  41
  42 #include "pcap/funcattrs.h"
  43
  44 #ifdef __cplusplus
  45 extern "C" {
  46 #endif
  47
  48 #ifndef HAVE_STRLCPY
  49  /*
  50   * Macro that does the same thing as strlcpy().
  51   */
  52  #if defined(_MSC_VER) || defined(__MINGW32__)
  53   /*
  54    * strncpy_s() is supported at least back to Visual
  55    * Studio 2005.
  56    */
  57   #define strlcpy(x, y, z) \
  58         strncpy_s((x), (z), (y), _TRUNCATE)
  59
  60  #else
  61   #define strlcpy(x, y, z) \
  62         (strncpy((x), (y), (z)), \
  63          ((z) <= 0 ? 0 : ((x)[(z) - 1] = '\0')), \
  64          (void) strlen((y)))
  65  #endif
  66 #endif
  67
  68 #ifndef HAVE_STRLCAT
  69  /*
  70   * Macro that does the same thing as strlcat().
  71   */
  72  #if defined(_MSC_VER) || defined(__MINGW32__)
  73   /*
  74    * strncat_s() is supported at least back to Visual
  75    * Studio 2005.
  76    */
  77   #define strlcat(x, y, z) \
  78         strncat_s((x), (z), (y), _TRUNCATE)
  79  #else
  80   /*
  81    * ANSI C says strncat() always null-terminates its first argument,
  82    * so 1) we don't need to explicitly null-terminate the string
  83    * ourselves and 2) we need to leave room for the null terminator.
  84    */
  85   #define strlcat(x, y, z) \
  86         strncat((x), (y), (z) - strlen((x)) - 1)
  87  #endif
  88 #endif
  89
  90 #ifdef _MSC_VER
  91   /*
  92    * If <crtdbg.h> has been included, and _DEBUG is defined, and
  93    * __STDC__ is zero, <crtdbg.h> will define strdup() to call
  94    * _strdup_dbg().  So if it's already defined, don't redefine
  95    * it.
  96    */
  97   #ifndef strdup
  98   #define strdup        _strdup
  99   #endif
 100 #endif
 101
 102 /*
 103  * On Windows, snprintf(), with that name and with C99 behavior - i.e.,
 104  * guaranteeing that the formatted string is null-terminated - didn't
 105  * appear until Visual Studio 2015.  Prior to that, the C runtime had
 106  * only _snprintf(), which *doesn't* guarantee that the string is
 107  * null-terminated if it is truncated due to the buffer being too
 108  * small.  We therefore can't just define snprintf to be _snprintf
 109  * and define vsnprintf to be _vsnprintf, as we're relying on null-
 110  * termination of strings in all cases.
 111  *
 112  * We also want to allow this to be built with versions of Visual Studio
 113  * prior to VS 2015, so we can't rely on snprintf() being present.
 114  *
 115  * And we want to make sure that, if we support plugins in the future,
 116  * a routine with C99 snprintf() behavior will be available to them.
 117  * We also don't want it to collide with the C library snprintf() if
 118  * there is one.
 119  *
 120  * So we make pcap_snprintf() and pcap_vsnprintf() available, either by
 121  * #defining them to be snprintf or vsnprintf, respectively, or by
 122  * defining our own versions and exporting them.
 123  */
 124 #ifdef HAVE_SNPRINTF
 125 #define pcap_snprintf snprintf
 126 #else
 127 extern int pcap_snprintf(char *, size_t, PCAP_FORMAT_STRING(const char *), ...)
 128     PCAP_PRINTFLIKE(3, 4);
 129 #endif
 130
 131 #ifdef HAVE_VSNPRINTF
 132 #define pcap_vsnprintf vsnprintf
 133 #else
 134 extern int pcap_vsnprintf(char *, size_t, const char *, va_list ap);
 135 #endif
 136
 137 #ifdef HAVE_STRTOK_R
 138   #define pcap_strtok_r strtok_r
 139 #else
 140   #ifdef _WIN32
 141     /*
 142      * Microsoft gives it a different name.
 143      */
 144     #define pcap_strtok_r       strtok_s
 145   #else
 146     /*
 147      * Define it ourselves.
 148      */
 149     #define NEED_STRTOK_R
 150     extern char *pcap_strtok_r(char *, const char *, char **);
 151   #endif
 152 #endif /* HAVE_STRTOK_R */
 153
 154 #ifdef _WIN32
 155   #if !defined(__cplusplus)
 156     #define inline __inline
 157   #endif
 158 #endif /* _WIN32 */
 159
 160 #ifdef __cplusplus
 161 }
 162 #endif
 163
 164 #endif