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#pragma once
#include <stdio.h>
#include <stdint.h>
#include <utility>
#include <map>
namespace fuzzing {
namespace datasource {
/* From: https://gist.github.com/underscorediscovery/81308642d0325fd386237cfa3b44785c */
inline uint64_t hash_64_fnv1a(const void* key, const uint64_t len) {
const char* data = (char*)key;
uint64_t hash = 0xcbf29ce484222325;
uint64_t prime = 0x100000001b3;
for(uint64_t i = 0; i < len; ++i) {
uint8_t value = data[i];
hash = hash ^ value;
hash *= prime;
}
return hash;
} //hash_64_fnv1a
// FNV1a c++11 constexpr compile time hash functions, 32 and 64 bit
// str should be a null terminated string literal, value should be left out
// e.g hash_32_fnv1a_const("example")
// code license: public domain or equivalent
// post: https://notes.underscorediscovery.com/constexpr-fnv1a/
constexpr uint32_t val_32_const = 0x811c9dc5;
constexpr uint32_t prime_32_const = 0x1000193;
constexpr uint64_t val_64_const = 0xcbf29ce484222325;
constexpr uint64_t prime_64_const = 0x100000001b3;
inline constexpr uint64_t ID(const char* const str, const uint64_t value = val_64_const) noexcept {
auto ret = (str[0] == '\0') ? value : ID(&str[1], (value ^ uint64_t(str[0])) * prime_64_const);
return ret;
}
inline constexpr std::pair<const char*, uint64_t> IDPair(const char* const str, const uint64_t value = val_64_const) noexcept {
return {str, ID(str, value)};
}
using IDMap = std::map<const char*, uint64_t>;
} /* namespace datasource */
} /* namespace fuzzing */
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