1/* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
2/*
3 * Copyright (c) 1993, 1994, 1995, 1996, 1997
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 *    must display the following acknowledgement:
16 *	This product includes software developed by the Computer Systems
17 *	Engineering Group at Lawrence Berkeley Laboratory.
18 * 4. Neither the name of the University nor of the Laboratory may be used
19 *    to endorse or promote products derived from this software without
20 *    specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#ifndef lib_pcap_funcattrs_h
36#define lib_pcap_funcattrs_h
37
38#include <pcap/compiler-tests.h>
39
40/*
41 * Attributes to apply to functions and their arguments, using various
42 * compiler-specific extensions.
43 */
44
45/*
46 * PCAP_API_DEF must be used when defining *data* exported from
47 * libpcap.  It can be used when defining *functions* exported
48 * from libpcap, but it doesn't have to be used there.  It
49 * should not be used in declarations in headers.
50 *
51 * PCAP_API must be used when *declaring* data or functions
52 * exported from libpcap; PCAP_API_DEF won't work on all platforms.
53 */
54
55#if defined(_WIN32)
56  /*
57   * For Windows:
58   *
59   *    when building libpcap:
60   *
61   *       if we're building it as a DLL, we have to declare API
62   *       functions with __declspec(dllexport);
63   *
64   *       if we're building it as a static library, we don't want
65   *       to do so.
66   *
67   *    when using libpcap:
68   *
69   *       if we're using the DLL, calls to its functions are a
70   *       little more efficient if they're declared with
71   *       __declspec(dllimport);
72   *
73   *       if we're not using the dll, we don't want to declare
74   *       them that way.
75   *
76   * So:
77   *
78   *    if pcap_EXPORTS is defined, we define PCAP_API_DEF as
79   *     __declspec(dllexport);
80   *
81   *    if PCAP_DLL is defined, we define PCAP_API_DEF as
82   *    __declspec(dllimport);
83   *
84   *    otherwise, we define PCAP_API_DEF as nothing.
85   */
86  #if defined(pcap_EXPORTS)
87    /*
88     * We're compiling libpcap as a DLL, so we should export functions
89     * in our API.
90     */
91    #define PCAP_API_DEF	__declspec(dllexport)
92  #elif defined(PCAP_DLL)
93    /*
94     * We're using libpcap as a DLL, so the calls will be a little more
95     * efficient if we explicitly import the functions.
96     */
97    #define PCAP_API_DEF	__declspec(dllimport)
98  #else
99    /*
100     * Either we're building libpcap as a static library, or we're using
101     * it as a static library, or we don't know for certain that we're
102     * using it as a dynamic library, so neither import nor export the
103     * functions explicitly.
104     */
105    #define PCAP_API_DEF
106  #endif
107#elif defined(MSDOS)
108  /* XXX - does this need special treatment? */
109  #define PCAP_API_DEF
110#else /* UN*X */
111  #ifdef pcap_EXPORTS
112    /*
113     * We're compiling libpcap as a (dynamic) shared library, so we should
114     * export functions in our API.  The compiler might be configured not
115     * to export functions from a shared library by default, so we might
116     * have to explicitly mark functions as exported.
117     */
118    #if PCAP_IS_AT_LEAST_GNUC_VERSION(3,4) \
119        || PCAP_IS_AT_LEAST_XL_C_VERSION(12,0)
120      /*
121       * GCC 3.4 or later, or some compiler asserting compatibility with
122       * GCC 3.4 or later, or XL C 13.0 or later, so we have
123       * __attribute__((visibility()).
124       */
125      #define PCAP_API_DEF	__attribute__((visibility("default")))
126    #elif PCAP_IS_AT_LEAST_SUNC_VERSION(5,5)
127      /*
128       * Sun C 5.5 or later, so we have __global.
129       * (Sun C 5.9 and later also have __attribute__((visibility()),
130       * but there's no reason to prefer it with Sun C.)
131       */
132      #define PCAP_API_DEF	__global
133    #else
134      /*
135       * We don't have anything to say.
136       */
137      #define PCAP_API_DEF
138    #endif
139  #else
140    /*
141     * We're not building libpcap.
142     */
143    #define PCAP_API_DEF
144  #endif
145#endif /* _WIN32/MSDOS/UN*X */
146
147#define PCAP_API	PCAP_API_DEF extern
148
149/*
150 * PCAP_NORETURN, before a function declaration, means "this function
151 * never returns".  (It must go before the function declaration, e.g.
152 * "extern PCAP_NORETURN func(...)" rather than after the function
153 * declaration, as the MSVC version has to go before the declaration.)
154 *
155 * PCAP_NORETURN_DEF, before a function *definition*, means "this
156 * function never returns"; it would be used only for static functions
157 * that are defined before any use, and thus have no declaration.
158 * (MSVC doesn't support that; I guess the "decl" in "__declspec"
159 * means "declaration", and __declspec doesn't work with definitions.)
160 */
161#if __has_attribute(noreturn) \
162    || PCAP_IS_AT_LEAST_GNUC_VERSION(2,5) \
163    || PCAP_IS_AT_LEAST_SUNC_VERSION(5,9) \
164    || PCAP_IS_AT_LEAST_XL_C_VERSION(10,1) \
165    || PCAP_IS_AT_LEAST_HP_C_VERSION(6,10)
166  /*
167   * Compiler with support for __attribute((noreturn)), or GCC 2.5 or
168   * later, or some compiler asserting compatibility with GCC 2.5 or
169   * later, or Solaris Studio 12 (Sun C 5.9) or later, or IBM XL C 10.1
170   * or later (do any earlier versions of XL C support this?), or HP aCC
171   * A.06.10 or later.
172   */
173  #define PCAP_NORETURN __attribute((noreturn))
174  #define PCAP_NORETURN_DEF __attribute((noreturn))
175#elif defined(_MSC_VER)
176  /*
177   * MSVC.
178   */
179  #define PCAP_NORETURN __declspec(noreturn)
180  #define PCAP_NORETURN_DEF
181#else
182  #define PCAP_NORETURN
183  #define PCAP_NORETURN_DEF
184#endif
185
186/*
187 * PCAP_PRINTFLIKE(x,y), after a function declaration, means "this function
188 * does printf-style formatting, with the xth argument being the format
189 * string and the yth argument being the first argument for the format
190 * string".
191 */
192#if __has_attribute(__format__) \
193    || PCAP_IS_AT_LEAST_GNUC_VERSION(2,3) \
194    || PCAP_IS_AT_LEAST_XL_C_VERSION(10,1) \
195    || PCAP_IS_AT_LEAST_HP_C_VERSION(6,10)
196  /*
197   * Compiler with support for it, or GCC 2.3 or later, or some compiler
198   * asserting compatibility with GCC 2.3 or later, or IBM XL C 10.1
199   * and later (do any earlier versions of XL C support this?),
200   * or HP aCC A.06.10 and later.
201   */
202  #define PCAP_PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y)))
203#else
204  #define PCAP_PRINTFLIKE(x,y)
205#endif
206
207/*
208 * PCAP_DEPRECATED(func, msg), after a function declaration, marks the
209 * function as deprecated.
210 *
211 * The first argument is the name of the function; the second argument is
212 * a string giving the warning message to use if the compiler supports that.
213 *
214 * (Thank you, Microsoft, for requiring the function name.)
215 */
216#if __has_attribute(deprecated) \
217    || PCAP_IS_AT_LEAST_GNUC_VERSION(4,5) \
218    || PCAP_IS_AT_LEAST_SUNC_VERSION(5,13)
219  /*
220   * Compiler that supports __has_attribute and __attribute__((deprecated)),
221   * or GCC 4.5 or later, or Sun/Oracle C 12.4 (Sun C 5.13) or later.
222   *
223   * Those support __attribute__((deprecated(msg))) (we assume, perhaps
224   * incorrectly, that anything that supports __has_attribute() is
225   * recent enough to support __attribute__((deprecated(msg)))).
226   */
227  #define PCAP_DEPRECATED(func, msg)	__attribute__((deprecated(msg)))
228#elif PCAP_IS_AT_LEAST_GNUC_VERSION(3,1)
229  /*
230   * GCC 3.1 through 4.4.
231   *
232   * Those support __attribute__((deprecated)) but not
233   * __attribute__((deprecated(msg))).
234   */
235  #define PCAP_DEPRECATED(func, msg)	__attribute__((deprecated))
236#elif (defined(_MSC_VER) && (_MSC_VER >= 1500)) && !defined(BUILDING_PCAP)
237  /*
238   * MSVC from Visual Studio 2008 or later, and we're not building
239   * libpcap itself.
240   *
241   * If we *are* building libpcap, we don't want this, as it'll warn
242   * us even if we *define* the function.
243   */
244  #define PCAP_DEPRECATED(func, msg)	__pragma(deprecated(func))
245#else
246  #define PCAP_DEPRECATED(func, msg)
247#endif
248
249/*
250 * For flagging arguments as format strings in MSVC.
251 */
252#ifdef _MSC_VER
253 #include <sal.h>
254 #if _MSC_VER > 1400
255  #define PCAP_FORMAT_STRING(p) _Printf_format_string_ p
256 #else
257  #define PCAP_FORMAT_STRING(p) __format_string p
258 #endif
259#else
260 #define PCAP_FORMAT_STRING(p) p
261#endif
262
263#endif /* lib_pcap_funcattrs_h */
264