ecency-mobile/ios/Pods/boost-for-react-native/boost/uuid/name_generator.hpp

126 lines
3.7 KiB
C++

// Boost name_generator.hpp header file ----------------------------------------------//
// Copyright 2010 Andy Tompkins.
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_UUID_NAME_GENERATOR_HPP
#define BOOST_UUID_NAME_GENERATOR_HPP
#include <boost/uuid/uuid.hpp>
#include <boost/uuid/sha1.hpp>
#include <boost/assert.hpp>
#include <string>
#include <cstring> // for strlen, wcslen
#ifdef BOOST_NO_STDC_NAMESPACE
namespace std {
using ::strlen;
using ::wcslen;
} //namespace std
#endif //BOOST_NO_STDC_NAMESPACE
namespace boost {
namespace uuids {
// generate a name-based uuid
// TODO: add in common namesspace uuids
class name_generator {
public:
typedef uuid result_type;
explicit name_generator(uuid const& namespace_uuid_)
: namespace_uuid(namespace_uuid_)
{}
uuid operator()(const char* name) {
reset();
process_characters(name, std::strlen(name));
return sha_to_uuid();
}
uuid operator()(const wchar_t* name) {
reset();
process_characters(name, std::wcslen(name));
return sha_to_uuid();
}
template <typename ch, typename char_traits, typename alloc>
uuid operator()(std::basic_string<ch, char_traits, alloc> const& name) {
reset();
process_characters(name.c_str(), name.length());
return sha_to_uuid();
}
uuid operator()(void const* buffer, std::size_t byte_count) {
reset();
sha.process_bytes(buffer, byte_count);
return sha_to_uuid();
};
private:
// we convert all characters to uint32_t so that each
// character is 4 bytes reguardless of sizeof(char) or
// sizeof(wchar_t). We want the name string on any
// platform / compiler to generate the same uuid
// except for char
template <typename char_type>
void process_characters(char_type const*const characters, size_t count) {
BOOST_ASSERT(sizeof(uint32_t) >= sizeof(char_type));
for (size_t i=0; i<count; i++) {
uint32_t c = characters[i];
sha.process_byte(static_cast<unsigned char>((c >> 0) & 0xFF));
sha.process_byte(static_cast<unsigned char>((c >> 8) & 0xFF));
sha.process_byte(static_cast<unsigned char>((c >> 16) & 0xFF));
sha.process_byte(static_cast<unsigned char>((c >> 24) & 0xFF));
}
}
void process_characters(char const*const characters, size_t count) {
sha.process_bytes(characters, count);
}
void reset()
{
sha.reset();
sha.process_bytes(namespace_uuid.begin(), namespace_uuid.size());
}
uuid sha_to_uuid()
{
unsigned int digest[5];
sha.get_digest(digest);
uuid u;
for (int i=0; i<4; ++i) {
*(u.begin() + i*4+0) = static_cast<uint8_t>((digest[i] >> 24) & 0xFF);
*(u.begin() + i*4+1) = static_cast<uint8_t>((digest[i] >> 16) & 0xFF);
*(u.begin() + i*4+2) = static_cast<uint8_t>((digest[i] >> 8) & 0xFF);
*(u.begin() + i*4+3) = static_cast<uint8_t>((digest[i] >> 0) & 0xFF);
}
// set variant
// must be 0b10xxxxxx
*(u.begin()+8) &= 0xBF;
*(u.begin()+8) |= 0x80;
// set version
// must be 0b0101xxxx
*(u.begin()+6) &= 0x5F; //0b01011111
*(u.begin()+6) |= 0x50; //0b01010000
return u;
}
private:
uuid namespace_uuid;
detail::sha1 sha;
};
}} // namespace boost::uuids
#endif // BOOST_UUID_NAME_GENERATOR_HPP