xref: /xnu-11215/bsd/net/net_sysctl.h (revision 8d741a5d)
1 /*
2  * Copyright (c) 2000-2024 Apple Inc. All rights reserved.
3  *
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8  * Version 2.0 (the 'License'). You may not use this file except in
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15  * Please obtain a copy of the License at
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18  * The Original Code and all software distributed under the License are
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20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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27  */
28 
29  #ifndef _NET_SYSCTL_H_
30  #define _NET_SYSCTL_H_
31 
32 #include <sys/cdefs.h>
33 #include <sys/sysctl.h>
34 /*
35  * Helper utilities for the sysctl procedures used
36  * by bsd networking.
37  */
38 
39 /*
40  * DECLARE_SYSCTL_HANDLER_ARG_ARRAY
41  *
42  * Helper macro to be invoked from a sysctl handler function.
43  *
44  * The macro compares the `arg2' sysctl handler argument
45  * with the `expected_array_size' macro parameter.
46  *
47  * If `arg2' is equal to `expected_array_size', the macro will
48  * define two local variables, the names of which are controlled
49  * by macro parameters:
50  *
51  *    element_type  *`array_var';
52  *    unsigned int   `len_var';
53  *
54  * The `array_var' local variable will be sized in accordance
55  * to the parameters. It does not use `__sized_by` annotation,
56  * to allow the body of the handler function to change the values,
57  * if needed.
58  *
59  * If `arg2' is not equal to `expected_array_size', the macro
60  * will return from the sysctl handler function with the
61  * EINVAL code.
62  */
63 #define DECLARE_SYSCTL_HANDLER_ARG_ARRAY(element_type,                     \
64 	    expected_array_size,                                               \
65 	    array_var,                                                         \
66 	    len_var)                                                           \
67     unsigned int len_var = (unsigned int)arg2;                             \
68     if (len_var != (expected_array_size)) {                                \
69 	    return EINVAL;                                                     \
70     }                                                                      \
71     element_type * array_var = __unsafe_forge_bidi_indexable(              \
72 	element_type *, arg1, len_var * sizeof(element_type))
73 
74 
75  #endif /* _NET_SYSCTL_H_ */
76