src/bthread/prime_offset.h

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// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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#ifndef BTHREAD_PRIME_OFFSET_H
#define BTHREAD_PRIME_OFFSET_H

#include "butil/fast_rand.h"
#include "butil/macros.h"

namespace bthread {
// Prime number offset for hash function.
inline size_t prime_offset(size_t seed) {
    uint32_t offsets[] = {
        #include "bthread/offset_inl.list"
    };
    return offsets[seed % ARRAY_SIZE(offsets)];
}

inline size_t prime_offset() {
    return prime_offset(butil::fast_rand());
}
}


#endif // BTHREAD_PRIME_OFFSET_H