lbrycrd/src/crypto/common.h
2017-03-29 11:26:08 -07:00

103 lines
2.2 KiB
C

// Copyright (c) 2014 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_CRYPTO_COMMON_H
#define BITCOIN_CRYPTO_COMMON_H
#if defined(HAVE_CONFIG_H)
#include "bitcoin-config.h"
#endif
#include <stdint.h>
#include <string.h>
#include "compat/endian.h"
uint16_t static inline ReadLE16(const unsigned char* ptr)
{
uint16_t x;
memcpy((char*)&x, ptr, 2);
return le16toh(x);
}
uint32_t static inline ReadLE32(const unsigned char* ptr)
{
uint32_t x;
memcpy((char*)&x, ptr, 4);
return le32toh(x);
}
uint64_t static inline ReadLE64(const unsigned char* ptr)
{
uint64_t x;
memcpy((char*)&x, ptr, 8);
return le64toh(x);
}
void static inline WriteLE16(unsigned char* ptr, uint16_t x)
{
uint16_t v = htole16(x);
memcpy(ptr, (char*)&v, 2);
}
void static inline WriteLE32(unsigned char* ptr, uint32_t x)
{
uint32_t v = htole32(x);
memcpy(ptr, (char*)&v, 4);
}
void static inline WriteLE64(unsigned char* ptr, uint64_t x)
{
uint64_t v = htole64(x);
memcpy(ptr, (char*)&v, 8);
}
uint32_t static inline ReadBE32(const unsigned char* ptr)
{
uint32_t x;
memcpy((char*)&x, ptr, 4);
return be32toh(x);
}
uint64_t static inline ReadBE64(const unsigned char* ptr)
{
uint64_t x;
memcpy((char*)&x, ptr, 8);
return be64toh(x);
}
void static inline WriteBE32(unsigned char* ptr, uint32_t x)
{
uint32_t v = htobe32(x);
memcpy(ptr, (char*)&v, 4);
}
void static inline WriteBE64(unsigned char* ptr, uint64_t x)
{
uint64_t v = htobe64(x);
memcpy(ptr, (char*)&v, 8);
}
/** Return the smallest number n such that (x >> n) == 0 (or 64 if the highest bit in x is set. */
uint64_t static inline CountBits(uint64_t x)
{
#ifdef HAVE_DECL___BUILTIN_CLZL
if (sizeof(unsigned long) >= sizeof(uint64_t)) {
return x ? 8 * sizeof(unsigned long) - __builtin_clzl(x) : 0;
}
#endif
#ifdef HAVE_DECL___BUILTIN_CLZLL
if (sizeof(unsigned long long) >= sizeof(uint64_t)) {
return x ? 8 * sizeof(unsigned long long) - __builtin_clzll(x) : 0;
}
#endif
int ret = 0;
while (x) {
x >>= 1;
++ret;
}
return ret;
}
#endif // BITCOIN_CRYPTO_COMMON_H