1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/* Copyright (C) 1992, 93, 94, 95, 96, 97, 98 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#ifndef _SYS_CDEFS_H
#define _SYS_CDEFS_H 1
#include <features.h>
/* Some user header file might have defined this before. */
#undef __P
#ifdef __GNUC__
/* GCC can always grok prototypes. For C++ programs we add throw()
to help it optimize the function calls. But this works only with
gcc 2.8.x and egcs. */
# if defined __cplusplus && __GNUC_MINOR__ >= 8
# define __THROW throw ()
# else
# define __THROW
# endif
# define __P(args) args __THROW
/* This macro will be used for functions which might take C++ callback
functions. */
# define __PMT(args) args
# define __DOTS , ...
#else /* Not GCC. */
# define __inline /* No inline functions. */
# if (defined __STDC__ && __STDC__) || defined __cplusplus
# define __P(args) args
# define __PMT(args) args
# define __const const
# define __signed signed
# define __volatile volatile
# define __DOTS , ...
# else /* Not ANSI C or C++. */
# define __P(args) () /* No prototypes. */
# define __PMT(args) ()
# define __const /* No ANSI C keywords. */
# define __signed
# define __volatile
# define __DOTS
# endif /* ANSI C or C++. */
#endif /* GCC. */
/* For these things, GCC behaves the ANSI way normally,
and the non-ANSI way under -traditional. */
#if defined __STDC__ && __STDC__
# define __CONCAT(x,y) x ## y
# define __STRING(x) #x
/* This is not a typedef so `const __ptr_t' does the right thing. */
# define __ptr_t void *
# define __long_double_t long double
#else
# define __CONCAT(x,y) x/**/y
# define __STRING(x) "x"
# define __ptr_t char *
# define __long_double_t long double
/* The BSD header files use the ANSI keywords unmodified (this means that
old programs may lose if they use the new keywords as identifiers), but
those names are not available under -traditional. We define them to
their __ versions, which are taken care of above. */
#ifdef __USE_BSD
# define const __const
# define signed __signed
# define volatile __volatile
#endif
#endif /* __STDC__ */
/* C++ needs to know that types and declarations are C, not C++. */
#ifdef __cplusplus
# define __BEGIN_DECLS extern "C" {
# define __END_DECLS }
#else
# define __BEGIN_DECLS
# define __END_DECLS
#endif
/* __asm__ ("xyz") is used throughout the headers to rename functions
at the assembly language level. This is wrapped by the __REDIRECT
macro, in order to support compilers that can do this some other
way. When compilers don't support asm-names at all, we have to do
preprocessor tricks instead (which don't have exactly the right
semantics, but it's the best we can do).
Example:
int __REDIRECT(setpgrp, __P((__pid_t pid, __pid_t pgrp)), setpgid); */
#if defined __GNUC__ && __GNUC__ >= 2
# define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
# define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
# define __ASMNAME2(prefix, cname) __STRING (prefix) cname
/*
#elif __SOME_OTHER_COMPILER__
# define __attribute__(xyz)
# define __REDIRECT(name, proto, alias) name proto; \
_Pragma("let " #name " = " #alias)
*/
#endif
/* GCC has various useful declarations that can be made with the
`__attribute__' syntax. All of the ways we use this do fine if
they are omitted for compilers that don't understand it. */
#if !defined __GNUC__ || __GNUC__ < 2
# define __attribute__(xyz) /* Ignore. */
#endif
/* It is possible to compile containing GCC extensions even if GCC is
run in pedantic mode if the uses are carefully marked using the
`__extension__' keyword. But this is not generally available before
version 2.8. */
#if !defined __GNUC__ || __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
# define __extension__ /* Ignore */
#endif
/* No current version of gcc knows the `restrict' keyword. Define it
for now unconditionally to the empty string. */
#define __restrict
#endif /* sys/cdefs.h */
|
