30 lines
739 B
C
30 lines
739 B
C
#ifndef COSMOPOLITAN_LIBC_ALG_BISECT_H_
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#define COSMOPOLITAN_LIBC_ALG_BISECT_H_
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#if !(__ASSEMBLER__ + __LINKER__ + 0)
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COSMOPOLITAN_C_START_
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forceinline void *bisect(const void *k, const void *data, size_t n, size_t size,
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int cmp(const void *a, const void *b, void *arg),
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void *arg) {
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int dir;
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const char *p, *pos;
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p = data;
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while (n > 0) {
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pos = p + size * (n / 2);
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dir = cmp(k, pos, arg);
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if (dir < 0) {
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n /= 2;
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} else if (dir > 0) {
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p = pos + size;
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n -= n / 2 + 1;
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} else {
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return (void *)pos;
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}
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}
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return NULL;
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}
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COSMOPOLITAN_C_END_
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#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
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#endif /* COSMOPOLITAN_LIBC_ALG_BISECT_H_ */
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