xref: /freebsd/contrib/libpcap/pcap/funcattrs.h (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
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 and later, or some compiler asserting compatibility with
122        * GCC 3.4 and later, or XL C 13.0 and 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 and 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  * Definitions to 1) indicate what version of libpcap first had a given
151  * API and 2) allow upstream providers whose build environments allow
152  * APIs to be designated as "first available in this release" to do so
153  * by appropriately defining them.
154  *
155  * On macOS, Apple can tweak this to make various APIs "weakly exported
156  * symbols" to make it easier for software that's distributed in binary
157  * form and that uses libpcap to run on multiple macOS versions and use
158  * new APIs when available.  (Yes, such third-party software exists -
159  * Wireshark provides binary packages for macOS, for example.  tcpdump
160  * doesn't count, as that's provided by Apple, so each release can
161  * come with a version compiled to use the APIs present in that release.)
162  *
163  * We don't tweak it that way ourselves because, if you're building
164  * and installing libpcap on macOS yourself, the APIs will be available
165  * no matter what OS version you're installing it on.
166  *
167  * For other platforms, we don't define them, leaving it up to
168  * others to do so based on their OS versions, if appropriate.
169  *
170  * We start with libpcap 0.4, as that was the last LBL release, and
171  * I've never seen earlier releases.
172  */
173 #ifdef __APPLE__
174 /*
175  * Apple - insert #include <os/availability.h> here, and replace the two
176  * #defines below with:
177  *
178  *   #define PCAP_API_AVAILABLE	API_AVAILABLE
179  *
180  * and adjust availabilities as necessary, including adding information
181  * about operating systems other than macOS.
182  */
183 #define PCAP_API_AVAILABLE(...)
184 #define PCAP_AVAILABLE_0_4	PCAP_API_AVAILABLE(macos(10.0))
185 #define PCAP_AVAILABLE_0_5	PCAP_API_AVAILABLE(macos(10.0))
186 #define PCAP_AVAILABLE_0_6	PCAP_API_AVAILABLE(macos(10.1))
187 #define PCAP_AVAILABLE_0_7	PCAP_API_AVAILABLE(macos(10.4))
188 #define PCAP_AVAILABLE_0_8	PCAP_API_AVAILABLE(macos(10.4))
189 #define PCAP_AVAILABLE_0_9	PCAP_API_AVAILABLE(macos(10.5))
190 #define PCAP_AVAILABLE_1_0	PCAP_API_AVAILABLE(macos(10.6))
191 /* #define PCAP_AVAILABLE_1_1	no routines added to the API */
192 #define PCAP_AVAILABLE_1_2	PCAP_API_AVAILABLE(macos(10.9))
193 /* #define PCAP_AVAILABLE_1_3	no routines added to the API */
194 /* #define PCAP_AVAILABLE_1_4	no routines added to the API */
195 #define PCAP_AVAILABLE_1_5	PCAP_API_AVAILABLE(macos(10.10))
196 /* #define PCAP_AVAILABLE_1_6	no routines added to the API */
197 #define PCAP_AVAILABLE_1_7	PCAP_API_AVAILABLE(macos(10.12))
198 #define PCAP_AVAILABLE_1_8	PCAP_API_AVAILABLE(macos(10.13))
199 #define PCAP_AVAILABLE_1_9	PCAP_API_AVAILABLE(macos(10.13))
200 /*
201  * The remote capture APIs are, in 1.9 and 1.10, usually only
202  * available in the library if the library was built with
203  * remote capture enabled.
204  *
205  * However, macOS Sonoma provides stub versions of those routine,
206  * which return an error.  This means that we need a separate
207  * availability indicator macro for those routines, so that
208  * progras built on macOS Sonoma that attempt to use weak
209  * importing and availability tests to use those routines
210  * if they're available will get those routines weakly imported,
211  * so that if they're run on releases prior to Sonoma, they
212  * won't get an error from dyld about those routines being
213  * missing in libpcap.  (If they don't use run-time availability
214  * tests, they will, instead, get crashes if they call one of
215  * those routines, as the addresses of those routines will be
216  * set to 0 by dyld, meaning the program will dereference a
217  * null pointer and crash when trying to call them.)
218  *
219  * (Not that it's useful to use those routines *anyway*, as they're
220  * stubs that always fail.  The stubs were necessary in order to
221  * support weak exporting at all.)
222  */
223 #define PCAP_AVAILABLE_1_9_REMOTE	PCAP_API_AVAILABLE(macos(14.0))
224 #define PCAP_AVAILABLE_1_10	PCAP_API_AVAILABLE(macos(12.1))
225 #define PCAP_AVAILABLE_1_10_REMOTE	PCAP_API_AVAILABLE(macos(14.0))
226 #define PCAP_AVAILABLE_1_11	/* not released yet, so not in macOS yet */
227 #else /* __APPLE__ */
228 #define PCAP_AVAILABLE_0_4
229 #define PCAP_AVAILABLE_0_5
230 #define PCAP_AVAILABLE_0_6
231 #define PCAP_AVAILABLE_0_7
232 #define PCAP_AVAILABLE_0_8
233 #define PCAP_AVAILABLE_0_9
234 #define PCAP_AVAILABLE_1_0
235 /* #define PCAP_AVAILABLE_1_1	no routines added to the API */
236 #define PCAP_AVAILABLE_1_2
237 /* #define PCAP_AVAILABLE_1_3	no routines added to the API */
238 /* #define PCAP_AVAILABLE_1_4	no routines added to the API */
239 #define PCAP_AVAILABLE_1_5
240 /* #define PCAP_AVAILABLE_1_6	no routines added to the API */
241 #define PCAP_AVAILABLE_1_7
242 #define PCAP_AVAILABLE_1_8
243 #define PCAP_AVAILABLE_1_9
244 #define PCAP_AVAILABLE_1_9_REMOTE
245 #define PCAP_AVAILABLE_1_10
246 #define PCAP_AVAILABLE_1_10_REMOTE
247 #define PCAP_AVAILABLE_1_11
248 #endif /* __APPLE__ */
249 
250 /*
251  * PCAP_NORETURN, before a function declaration, means "this function
252  * never returns".  (It must go before the function declaration, e.g.
253  * "extern PCAP_NORETURN func(...)" rather than after the function
254  * declaration, as the MSVC version has to go before the declaration.)
255  *
256  * PCAP_NORETURN_DEF, before a function *definition*, means "this
257  * function never returns"; it would be used only for static functions
258  * that are defined before any use, and thus have no declaration.
259  * (MSVC doesn't support that; I guess the "decl" in "__declspec"
260  * means "declaration", and __declspec doesn't work with definitions.)
261  */
262 #if __has_attribute(noreturn) \
263     || PCAP_IS_AT_LEAST_GNUC_VERSION(2,5) \
264     || PCAP_IS_AT_LEAST_SUNC_VERSION(5,9) \
265     || PCAP_IS_AT_LEAST_XL_C_VERSION(7,0) \
266     || PCAP_IS_AT_LEAST_HP_C_VERSION(6,10) \
267     || __TINYC__
268   /*
269    * Compiler with support for __attribute((noreturn)), or GCC 2.5 and
270    * later, or some compiler asserting compatibility with GCC 2.5 and
271    * later, or Solaris Studio 12 (Sun C 5.9) and later, or IBM XL C 7.0
272    * and later (do any earlier versions of XL C support this?), or HP aCC
273    * A.06.10 and later, or current TinyCC.
274    */
275   #define PCAP_NORETURN __attribute((noreturn))
276   #define PCAP_NORETURN_DEF __attribute((noreturn))
277 #elif defined(_MSC_VER)
278   /*
279    * MSVC.
280    */
281   #define PCAP_NORETURN __declspec(noreturn)
282   #define PCAP_NORETURN_DEF
283 #else
284   #define PCAP_NORETURN
285   #define PCAP_NORETURN_DEF
286 #endif
287 
288 /*
289  * PCAP_PRINTFLIKE(x,y), after a function declaration, means "this function
290  * does printf-style formatting, with the xth argument being the format
291  * string and the yth argument being the first argument for the format
292  * string".
293  */
294 #if __has_attribute(__format__) \
295     || PCAP_IS_AT_LEAST_GNUC_VERSION(2,3) \
296     || PCAP_IS_AT_LEAST_XL_C_VERSION(7,0) \
297     || PCAP_IS_AT_LEAST_HP_C_VERSION(6,10)
298   /*
299    * Compiler with support for it, or GCC 2.3 and later, or some compiler
300    * asserting compatibility with GCC 2.3 and later, or IBM XL C 7.0
301    * and later (do any earlier versions of XL C support this?),
302    * or HP aCC A.06.10 and later.
303    */
304   #define PCAP_PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y)))
305 #else
306   #define PCAP_PRINTFLIKE(x,y)
307 #endif
308 
309 /*
310  * PCAP_DEPRECATED(func, msg), after a function declaration, marks the
311  * function as deprecated.
312  *
313  * The argument is a string giving the warning message to use if the
314  * compiler supports that.
315  */
316 #if __has_attribute(deprecated) \
317     || PCAP_IS_AT_LEAST_GNUC_VERSION(4,5) \
318     || PCAP_IS_AT_LEAST_SUNC_VERSION(5,13)
319   /*
320    * Compiler that supports __has_attribute and __attribute__((deprecated)),
321    * or GCC 4.5 and later, or Sun/Oracle C 12.4 (Sun C 5.13) and later.
322    *
323    * Those support __attribute__((deprecated(msg))) (we assume, perhaps
324    * incorrectly, that anything that supports __has_attribute() is
325    * recent enough to support __attribute__((deprecated(msg)))).
326    */
327   #define PCAP_DEPRECATED(msg)	__attribute__((deprecated(msg)))
328 #elif PCAP_IS_AT_LEAST_GNUC_VERSION(3,1)
329   /*
330    * GCC 3.1 through 4.4.
331    *
332    * Those support __attribute__((deprecated)) but not
333    * __attribute__((deprecated(msg))).
334    */
335   #define PCAP_DEPRECATED(msg)	__attribute__((deprecated))
336 #elif defined(_MSC_VER) && !defined(BUILDING_PCAP)
337   /*
338    * MSVC, and we're not building libpcap itself; it's VS 2015
339    * and later, so we have __declspec(deprecated(...)).
340    *
341    * If we *are* building libpcap, we don't want this, as it'll warn
342    * us even if we *define* the function.
343    */
344   #define PCAP_DEPRECATED(msg)	_declspec(deprecated(msg))
345 #else
346   #define PCAP_DEPRECATED(msg)
347 #endif
348 
349 /*
350  * For flagging arguments as format strings in MSVC.
351  */
352 #ifdef _MSC_VER
353  #include <sal.h>
354  #define PCAP_FORMAT_STRING(p) _Printf_format_string_ p
355 #else
356  #define PCAP_FORMAT_STRING(p) p
357 #endif
358 
359 #endif /* lib_pcap_funcattrs_h */
360