32 lines
1.0 KiB
C
32 lines
1.0 KiB
C
#ifndef COSMOPOLITAN_LIBC_ALG_REVERSE_H_
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#define COSMOPOLITAN_LIBC_ALG_REVERSE_H_
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#include "libc/bits/xchg.h"
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#if !(__ASSEMBLER__ + __LINKER__ + 0)
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/**
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* Reverses array.
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*
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* @param ARRAY is a typed array or a pointer to one
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* @param COUNT is the number of items
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* @return pointer to start of array
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* @see ARRAYLEN()
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*/
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#define reverse(ARRAY, COUNT) \
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({ \
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autotype(&(ARRAY)[0]) Array = (ARRAY); \
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size_t Count = (COUNT); \
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if (Count) { \
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size_t Start = 0; \
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size_t End = Count - 1; \
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while (Start < End) { \
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xchg(&Array[Start], &Array[End]); \
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++Start; \
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--End; \
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} \
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} \
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Array; \
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})
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#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
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#endif /* COSMOPOLITAN_LIBC_ALG_REVERSE_H_ */
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