Chris@16: // Boost name_generator.hpp header file  ----------------------------------------------//
Chris@16: 
Chris@16: // Copyright 2010 Andy Tompkins.
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: #ifndef BOOST_UUID_NAME_GENERATOR_HPP
Chris@16: #define BOOST_UUID_NAME_GENERATOR_HPP
Chris@16: 
Chris@16: #include <boost/uuid/uuid.hpp>
Chris@16: #include <boost/uuid/sha1.hpp>
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <string>
Chris@16: #include <cstring> // for strlen, wcslen
Chris@16: 
Chris@16: #ifdef BOOST_NO_STDC_NAMESPACE
Chris@16: namespace std {
Chris@16:     using ::strlen;
Chris@16:     using ::wcslen;
Chris@16: } //namespace std
Chris@16: #endif //BOOST_NO_STDC_NAMESPACE
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace uuids {
Chris@16: 
Chris@16: // generate a name-based uuid
Chris@16: // TODO: add in common namesspace uuids
Chris@16: class name_generator {
Chris@16: public:
Chris@16:     typedef uuid result_type;
Chris@16: 
Chris@101:     explicit name_generator(uuid const& namespace_uuid_)
Chris@101:         : namespace_uuid(namespace_uuid_)
Chris@16:     {}
Chris@16: 
Chris@16:     uuid operator()(const char* name) {
Chris@16:         reset();
Chris@16:         process_characters(name, std::strlen(name));
Chris@16:         return sha_to_uuid();
Chris@16:     }
Chris@16: 
Chris@16:     uuid operator()(const wchar_t* name) {
Chris@16:         reset();
Chris@16:         process_characters(name, std::wcslen(name));
Chris@16:         return sha_to_uuid();
Chris@16:     }
Chris@16: 
Chris@16:     template <typename ch, typename char_traits, typename alloc>
Chris@16:     uuid operator()(std::basic_string<ch, char_traits, alloc> const& name) {
Chris@16:         reset();
Chris@16:         process_characters(name.c_str(), name.length());
Chris@16:         return sha_to_uuid();
Chris@16:     }
Chris@16:     
Chris@16:     uuid operator()(void const* buffer, std::size_t byte_count) {
Chris@16:         reset();
Chris@16:         sha.process_bytes(buffer, byte_count);
Chris@16:         return sha_to_uuid();
Chris@16:     };
Chris@16: 
Chris@16: private:
Chris@16:     // we convert all characters to uint32_t so that each
Chris@16:     // character is 4 bytes reguardless of sizeof(char) or
Chris@16:     // sizeof(wchar_t).  We want the name string on any
Chris@16:     // platform / compiler to generate the same uuid
Chris@16:     // except for char
Chris@16:     template <typename char_type>
Chris@16:     void process_characters(char_type const*const characters, size_t count) {
Chris@16:         BOOST_ASSERT(sizeof(uint32_t) >= sizeof(char_type));
Chris@16: 
Chris@16:         for (size_t i=0; i<count; i++) {
Chris@16:             uint32_t c = characters[i];
Chris@101:             sha.process_byte(static_cast<unsigned char>((c >>  0) & 0xFF));
Chris@101:             sha.process_byte(static_cast<unsigned char>((c >>  8) & 0xFF));
Chris@101:             sha.process_byte(static_cast<unsigned char>((c >> 16) & 0xFF));
Chris@101:             sha.process_byte(static_cast<unsigned char>((c >> 24) & 0xFF));
Chris@16:         }
Chris@16:     }
Chris@16:     
Chris@16:     void process_characters(char const*const characters, size_t count) {
Chris@16:         sha.process_bytes(characters, count);
Chris@16:     }
Chris@16: 
Chris@16:     void reset()
Chris@16:     {
Chris@16:         sha.reset();
Chris@16:         sha.process_bytes(namespace_uuid.begin(), namespace_uuid.size());
Chris@16:     }
Chris@16:     
Chris@16:     uuid sha_to_uuid()
Chris@16:     {
Chris@16:         unsigned int digest[5];
Chris@16: 
Chris@16:         sha.get_digest(digest);
Chris@16: 
Chris@16:         uuid u;
Chris@16:         for (int i=0; i<4; ++i) {
Chris@101:             *(u.begin() + i*4+0) = static_cast<uint8_t>((digest[i] >> 24) & 0xFF);
Chris@101:             *(u.begin() + i*4+1) = static_cast<uint8_t>((digest[i] >> 16) & 0xFF);
Chris@101:             *(u.begin() + i*4+2) = static_cast<uint8_t>((digest[i] >> 8) & 0xFF);
Chris@101:             *(u.begin() + i*4+3) = static_cast<uint8_t>((digest[i] >> 0) & 0xFF);
Chris@16:         }
Chris@16: 
Chris@16:         // set variant
Chris@16:         // must be 0b10xxxxxx
Chris@16:         *(u.begin()+8) &= 0xBF;
Chris@16:         *(u.begin()+8) |= 0x80;
Chris@16: 
Chris@16:         // set version
Chris@16:         // must be 0b0101xxxx
Chris@16:         *(u.begin()+6) &= 0x5F; //0b01011111
Chris@16:         *(u.begin()+6) |= 0x50; //0b01010000
Chris@16: 
Chris@16:         return u;
Chris@16:     }
Chris@16: 
Chris@16: private:
Chris@16:     uuid namespace_uuid;
Chris@16:     detail::sha1 sha;
Chris@16: };
Chris@16: 
Chris@16: }} // namespace boost::uuids
Chris@16: 
Chris@16: #endif // BOOST_UUID_NAME_GENERATOR_HPP