Home | History | Annotate | Download | only in pcap
      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 and
    168    * later, or Solaris Studio 12 (Sun C 5.9) and later, or IBM XL C 10.1
    169    * and later (do any earlier versions of XL C support this?), or
    170    * HP aCC A.06.10 and later.
    171    */
    172   #define PCAP_NORETURN __attribute((noreturn))
    173   #define PCAP_NORETURN_DEF __attribute((noreturn))
    174 #elif defined(_MSC_VER)
    175   /*
    176    * MSVC.
    177    */
    178   #define PCAP_NORETURN __declspec(noreturn)
    179   #define PCAP_NORETURN_DEF
    180 #else
    181   #define PCAP_NORETURN
    182   #define PCAP_NORETURN_DEF
    183 #endif
    184 
    185 /*
    186  * PCAP_PRINTFLIKE(x,y), after a function declaration, means "this function
    187  * does printf-style formatting, with the xth argument being the format
    188  * string and the yth argument being the first argument for the format
    189  * string".
    190  */
    191 #if __has_attribute(__format__) \
    192     || PCAP_IS_AT_LEAST_GNUC_VERSION(2,3) \
    193     || PCAP_IS_AT_LEAST_XL_C_VERSION(10,1) \
    194     || PCAP_IS_AT_LEAST_HP_C_VERSION(6,10)
    195   /*
    196    * Compiler with support for it, or GCC 2.3 and later, or IBM XL C 10.1
    197    * and later (do any earlier versions of XL C support this?),
    198    * or HP aCC A.06.10 and later.
    199    */
    200   #define PCAP_PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y)))
    201 #else
    202   #define PCAP_PRINTFLIKE(x,y)
    203 #endif
    204 
    205 /*
    206  * PCAP_DEPRECATED(func, msg), after a function declaration, marks the
    207  * function as deprecated.
    208  *
    209  * The first argument is the name of the function; the second argument is
    210  * a string giving the warning message to use if the compiler supports that.
    211  *
    212  * (Thank you, Microsoft, for requiring the function name.)
    213  */
    214 #if __has_attribute(deprecated) \
    215     || PCAP_IS_AT_LEAST_GNUC_VERSION(4,5) \
    216     || PCAP_IS_AT_LEAST_SUNC_VERSION(5,13)
    217   /*
    218    * Compiler that supports __has_attribute and __attribute__((deprecated)),
    219    * or GCC 4.5 and later, or Sun/Oracle C 12.4 (Sun C 5.13) or later.
    220    *
    221    * Those support __attribute__((deprecated(msg))) (we assume, perhaps
    222    * incorrectly, that anything that supports __has_attribute() is
    223    * recent enough to support __attribute__((deprecated(msg)))).
    224    */
    225   #define PCAP_DEPRECATED(func, msg)	__attribute__((deprecated(msg)))
    226 #elif PCAP_IS_AT_LEAST_GNUC_VERSION(3,1)
    227   /*
    228    * GCC 3.1 through 4.4.
    229    *
    230    * Those support __attribute__((deprecated)) but not
    231    * __attribute__((deprecated(msg))).
    232    */
    233   #define PCAP_DEPRECATED(func, msg)	__attribute__((deprecated))
    234 #elif (defined(_MSC_VER) && (_MSC_VER >= 1500)) && !defined(BUILDING_PCAP)
    235   /*
    236    * MSVC from Visual Studio 2008 or later, and we're not building
    237    * libpcap itself.
    238    *
    239    * If we *are* building libpcap, we don't want this, as it'll warn
    240    * us even if we *define* the function.
    241    */
    242   #define PCAP_DEPRECATED(func, msg)	__pragma(deprecated(func))
    243 #else
    244   #define PCAP_DEPRECATED(func, msg)
    245 #endif
    246 
    247 /*
    248  * For flagging arguments as format strings in MSVC.
    249  */
    250 #ifdef _MSC_VER
    251  #include <sal.h>
    252  #if _MSC_VER > 1400
    253   #define PCAP_FORMAT_STRING(p) _Printf_format_string_ p
    254  #else
    255   #define PCAP_FORMAT_STRING(p) __format_string p
    256  #endif
    257 #else
    258  #define PCAP_FORMAT_STRING(p) p
    259 #endif
    260 
    261 #endif /* lib_pcap_funcattrs_h */
    262