C Standard Library Extensions  1.2.3
cxmacros.h
1 /*
2  * This file is part of the ESO C Extension Library
3  * Copyright (C) 2001-2017 European Southern Observatory
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 
21 /*
22  * This file MUST not include any other cext header file.
23  */
24 
25 #ifndef CX_MACROS_H
26 #define CX_MACROS_H
27 
28 
29 /*
30  * Get the system's definition of NULL from stddef.h
31  */
32 
33 #include <stddef.h>
34 
35 
36 /*
37  * An alias for __extension__
38  */
39 
40 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 8)
41 # define CX_GNUC_EXTENSION __extension__
42 #else
43 # define CX_GNUC_EXTENSION
44 #endif
45 
46 
47 /*
48  * Macros for the GNU compiler function attributes
49  */
50 
51 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
52 # define CX_GNUC_PURE __attribute__((__pure__))
53 # define CX_GNUC_MALLOC __attribute__((__malloc__))
54 #else
55 # define G_GNUC_PURE
56 # define G_GNUC_MALLOC
57 #endif
58 
59 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4)
60 # define CX_GNUC_PRINTF(fmt_idx, arg_idx) \
61  __attribute__((__format__ (__printf__, fmt_idx, arg_idx)))
62 # define CX_GNUC_SCANF(fmt_idx, arg_idx) \
63  __attribute__((__format__ (__scanf__, fmt_idx, arg_idx)))
64 # define CX_GNUC_FORMAT(arg_idx) __attribute__((__format_arg__ (arg_idx)))
65 # define CX_GNUC_NORETURN __attribute__((__noreturn__))
66 # define CX_GNUC_CONST __attribute__((__const__))
67 # define CX_GNUC_UNUSED __attribute__((__unused__))
68 #else
69 # define CX_GNUC_PRINTF(fmt_idx, arg_idx)
70 # define CX_GNUC_SCANF(fmt_idx, arg_idx)
71 # define CX_GNUC_FORMAT(arg_idx)
72 # define CX_GNUC_NORETURN
73 # define CX_GNUC_CONST
74 # define CX_GNUC_UNUSED
75 #endif
76 
77 
78 /*
79  * Wrap the gcc __PRETTY_FUNCTION__ and __FUNCTION__ variables with macros.
80  */
81 
82 #if defined (__GNUC__) && (__GNUC__ < 3)
83 # define CX_GNUC_FUNCTION __FUNCTION__
84 # define CX_GNUC_PRETTY_FUNCTION __PRETTY_FUNCTION__
85 #else /* !__GNUC__ */
86 # define CX_GNUC_FUNCTION ""
87 # define CX_GNUC_PRETTY_FUNCTION ""
88 #endif /* !__GNUC__ */
89 
90 #define CX_STRINGIFY(macro) CX_STRINGIFY_ARG(macro)
91 #define CX_STRINGIFY_ARG(contents) #contents
92 
93 
94 /*
95  * String identifier for the current code position
96  */
97 
98 #if defined (__GNUC__) && (__GNUC__ < 3)
99 # define CX_CODE_POS __FILE__ ":" CX_STRINGIFY(__LINE__) ":" __PRETTY_FUNCTION__ "()"
100 #else
101 # define CX_CODE_POS __FILE__ ":" CX_STRINGIFY(__LINE__)
102 #endif
103 
104 
105 /*
106  * Current function identifier
107  */
108 #if defined (__GNUC__)
109 # define CX_FUNC_NAME ((const char*) (__PRETTY_FUNCTION__))
110 #elif defined (__STDC_VERSION__) && __STDC_VERSION__ >= 19901L
111 # define CX_FUNC_NAME ((const char*) (__func__))
112 #else
113 # define CX_FUNC_NAME ((const char*) ("???"))
114 #endif
115 
116 
117 /*
118  * C code guard
119  */
120 
121 #undef CX_BEGIN_DECLS
122 #undef CX_END_DECLS
123 
124 #ifdef __cplusplus
125 # define CX_BEGIN_DECLS extern "C" {
126 # define CX_END_DECLS }
127 #else
128 # define CX_BEGIN_DECLS /* empty */
129 # define CX_END_DECLS /* empty */
130 #endif
131 
132 
133 /*
134  * Some popular macros. If the system provides already a definition for some
135  * of them this definition is used, assuming the definition is correct.
136  */
137 
138 #ifndef NULL
139 # ifdef __cplusplus
140 # define NULL (0L)
141 # else /* !__cplusplus */
142 # define NULL ((void *) 0)
143 # endif /* !__cplusplus */
144 #endif
145 
146 #ifndef FALSE
147 # define FALSE (0)
148 #endif
149 
150 #ifndef TRUE
151 # define TRUE (!FALSE)
152 #endif
153 
154 #ifndef CX_MIN
155 # define CX_MIN(a, b) ((a) < (b) ? (a) : (b))
156 #endif
157 
158 #ifndef CX_MAX
159 # define CX_MAX(a, b) ((a) > (b) ? (a) : (b))
160 #endif
161 
162 #ifndef CX_ABS
163 # define CX_ABS(a) ((a) < (0) ? -(a) : (a))
164 #endif
165 
166 #ifndef CX_CLAMP
167 # define CX_CLAMP(a, low, high) (((a) > (high)) ? (high) : (((a) < (low)) ? (low) : (a)))
168 #endif
169 
170 
171 /*
172  * Number of elements in an array
173  */
174 
175 #define CX_N_ELEMENTS(array) (sizeof (array) / sizeof ((array)[0]))
176 
177 #endif /* CX_MACROS_H */