26 lines
889 B
C
26 lines
889 B
C
/* CC0 (Public domain) - see LICENSE file for details */
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#ifndef CCAN_ARRAY_SIZE_H
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#define CCAN_ARRAY_SIZE_H
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#include "config.h"
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#include <ccan/build_assert/build_assert.h>
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/**
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* ARRAY_SIZE - get the number of elements in a visible array
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* @arr: the array whose size you want.
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*
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* This does not work on pointers, or arrays declared as [], or
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* function parameters. With correct compiler support, such usage
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* will cause a build error (see build_assert).
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*/
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#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + _array_size_chk(arr))
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#if HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
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/* Two gcc extensions.
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* &a[0] degrades to a pointer: a different type from an array */
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#define _array_size_chk(arr) \
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BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(typeof(arr), \
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typeof(&(arr)[0])))
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#else
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#define _array_size_chk(arr) 0
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#endif
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#endif /* CCAN_ALIGNOF_H */
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