xref: /freebsd/contrib/libpcap/portability.h (revision f68801df100565820b35631a8709229141537baa)
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
165