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lh9ed821d2023-04-07 01:36:19 -07001#ifndef __CARES_RULES_H
2#define __CARES_RULES_H
3
4
5/* Copyright (C) 2009 by Daniel Stenberg et al
6 *
7 * Permission to use, copy, modify, and distribute this software and its
8 * documentation for any purpose and without fee is hereby granted, provided
9 * that the above copyright notice appear in all copies and that both that
10 * copyright notice and this permission notice appear in supporting
11 * documentation, and that the name of M.I.T. not be used in advertising or
12 * publicity pertaining to distribution of the software without specific,
13 * written prior permission. M.I.T. makes no representations about the
14 * suitability of this software for any purpose. It is provided "as is"
15 * without express or implied warranty.
16 */
17
18/* ================================================================ */
19/* COMPILE TIME SANITY CHECKS */
20/* ================================================================ */
21
22/*
23 * NOTE 1:
24 * -------
25 *
26 * All checks done in this file are intentionally placed in a public
27 * header file which is pulled by ares.h when an application is
28 * being built using an already built c-ares library. Additionally
29 * this file is also included and used when building the library.
30 *
31 * If compilation fails on this file it is certainly sure that the
32 * problem is elsewhere. It could be a problem in the ares_build.h
33 * header file, or simply that you are using different compilation
34 * settings than those used to build the library.
35 *
36 * Nothing in this file is intended to be modified or adjusted by the
37 * c-ares library user nor by the c-ares library builder.
38 *
39 * Do not deactivate any check, these are done to make sure that the
40 * library is properly built and used.
41 *
42 * You can find further help on the c-ares development mailing list:
43 * http://cool.haxx.se/mailman/listinfo/c-ares/
44 *
45 * NOTE 2
46 * ------
47 *
48 * Some of the following compile time checks are based on the fact
49 * that the dimension of a constant array can not be a negative one.
50 * In this way if the compile time verification fails, the compilation
51 * will fail issuing an error. The error description wording is compiler
52 * dependent but it will be quite similar to one of the following:
53 *
54 * "negative subscript or subscript is too large"
55 * "array must have at least one element"
56 * "-1 is an illegal array size"
57 * "size of array is negative"
58 *
59 * If you are building an application which tries to use an already
60 * built c-ares library and you are getting this kind of errors on
61 * this file, it is a clear indication that there is a mismatch between
62 * how the library was built and how you are trying to use it for your
63 * application. Your already compiled or binary library provider is the
64 * only one who can give you the details you need to properly use it.
65 */
66
67/*
68 * Verify that some macros are actually defined.
69 */
70
71#ifndef CARES_TYPEOF_ARES_SOCKLEN_T
72# error "CARES_TYPEOF_ARES_SOCKLEN_T definition is missing!"
73 Error Compilation_aborted_CARES_TYPEOF_ARES_SOCKLEN_T_is_missing
74#endif
75
76/*
77 * Macros private to this header file.
78 */
79
80#define CareschkszEQ(t, s) sizeof(t) == s ? 1 : -1
81
82#define CareschkszGE(t1, t2) sizeof(t1) >= sizeof(t2) ? 1 : -1
83
84/*
85 * Verify that the size previously defined and expected for
86 * ares_socklen_t is actually the the same as the one reported
87 * by sizeof() at compile time.
88 */
89
90typedef char
91 __cares_rule_02__
92 [CareschkszEQ(ares_socklen_t, sizeof(CARES_TYPEOF_ARES_SOCKLEN_T))];
93
94/*
95 * Verify at compile time that the size of ares_socklen_t as reported
96 * by sizeof() is greater or equal than the one reported for int for
97 * the current compilation.
98 */
99
100typedef char
101 __cares_rule_03__
102 [CareschkszGE(ares_socklen_t, int)];
103
104/* ================================================================ */
105/* EXTERNALLY AND INTERNALLY VISIBLE DEFINITIONS */
106/* ================================================================ */
107
108/*
109 * Get rid of macros private to this header file.
110 */
111
112#undef CareschkszEQ
113#undef CareschkszGE
114
115/*
116 * Get rid of macros not intended to exist beyond this point.
117 */
118
119#undef CARES_PULL_WS2TCPIP_H
120#undef CARES_PULL_SYS_TYPES_H
121#undef CARES_PULL_SYS_SOCKET_H
122
123#undef CARES_TYPEOF_ARES_SOCKLEN_T
124
125#endif /* __CARES_RULES_H */