xref: /dragonfly/contrib/tcpdump/funcattrs.h (revision 0de61e28)
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_funcattrs_h
36 #define lib_funcattrs_h
37 
38 /*
39  * Attributes to apply to functions and their arguments, using various
40  * compiler-specific extensions.
41  */
42 
43 /*
44  * This was introduced by Clang:
45  *
46  *     http://clang.llvm.org/docs/LanguageExtensions.html#has-attribute
47  *
48  * in some version (which version?); it has been picked up by GCC 5.0.
49  */
50 #ifndef __has_attribute
51   /*
52    * It's a macro, so you can check whether it's defined to check
53    * whether it's supported.
54    *
55    * If it's not, define it to always return 0, so that we move on to
56    * the fallback checks.
57    */
58   #define __has_attribute(x) 0
59 #endif
60 
61 /*
62  * NORETURN, before a function declaration, means "this function
63  * never returns".  (It must go before the function declaration, e.g.
64  * "extern NORETURN func(...)" rather than after the function
65  * declaration, as the MSVC version has to go before the declaration.)
66  */
67 #if __has_attribute(noreturn) \
68     || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 205)) \
69     || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590)) \
70     || (defined(__xlC__) && __xlC__ >= 0x0A01) \
71     || (defined(__HP_aCC) && __HP_aCC >= 61000)
72   /*
73    * Compiler with support for __attribute((noreturn)), or GCC 2.5 and
74    * later, or Solaris Studio 12 (Sun C 5.9) and later, or IBM XL C 10.1
75    * and later (do any earlier versions of XL C support this?), or
76    * HP aCC A.06.10 and later.
77    */
78   #define NORETURN __attribute((noreturn))
79 #elif defined(_MSC_VER)
80   /*
81    * MSVC.
82    */
83   #define NORETURN __declspec(noreturn)
84 #else
85   #define NORETURN
86 #endif
87 
88 /*
89  * PRINTFLIKE(x,y), after a function declaration, means "this function
90  * does printf-style formatting, with the xth argument being the format
91  * string and the yth argument being the first argument for the format
92  * string".
93  */
94 #if __has_attribute(__format__) \
95     || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 203)) \
96     || (defined(__xlC__) && __xlC__ >= 0x0A01) \
97     || (defined(__HP_aCC) && __HP_aCC >= 61000)
98   /*
99    * Compiler with support for it, or GCC 2.3 and later, or IBM XL C 10.1
100    * and later (do any earlier versions of XL C support this?),
101    * or HP aCC A.06.10 and later.
102    */
103   #define PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y)))
104 #else
105   #define PRINTFLIKE(x,y)
106 #endif
107 
108 /*
109  * For flagging arguments as format strings in MSVC.
110  */
111 #if _MSC_VER >= 1400
112  #include <sal.h>
113  #if _MSC_VER > 1400
114   #define FORMAT_STRING(p) _Printf_format_string_ p
115  #else
116   #define FORMAT_STRING(p) __format_string p
117  #endif
118 #else
119  #define FORMAT_STRING(p) p
120 #endif
121 
122 #endif /* lib_funcattrs_h */
123