sole.h

 
 
#pragma once
#include <stdint.h>
#include <stdio.h>     // for size_t; should be stddef.h instead; however, clang+archlinux fails when compiling it (@Travis-Ci)
#include <sys/types.h> // for uint32_t; should be stdint.h instead; however, GCC 5 on OSX fails when compiling it (See issue #11)
#include <functional>
#include <string>
 
// public API
 
namespace sole
{
    // 128-bit basic UUID type that allows comparison and sorting.
    // Use .str() for printing and .pretty() for pretty printing.
    // Also, ostream friendly.
    struct uuid
    {
        uint64_t ab;
        uint64_t cd;
 
        bool operator==( const uuid &other ) const;
        bool operator!=( const uuid &other ) const;
        bool operator <( const uuid &other ) const;
 
        std::string base62() const;
        std::string str() const;
 
        template<typename ostream>
        inline friend ostream &operator<<( ostream &os, const uuid &self ) {
            return os << self.str(), os;
        }
    };
 
    // Generators
    uuid uuid4(); // UUID v4, pros: anonymous, fast; con: uuids "can clash"
 
    // Rebuilders
    uuid rebuild( uint64_t ab, uint64_t cd );
    uuid rebuild( const std::string &uustr );
}
 
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable:4127)
#endif
 
namespace std {
    template<>
    struct hash< sole::uuid > {
    public:
        // hash functor: hash uuid to size_t value by pseudorandomizing transform
        size_t operator()( const sole::uuid &uuid ) const {
            if( sizeof(size_t) > 4 ) {
                return size_t( uuid.ab ^ uuid.cd );
            } else {
                uint64_t hash64 = uuid.ab ^ uuid.cd;
                return size_t( uint32_t( hash64 >> 32 ) ^ uint32_t( hash64 ) );
            }
        }
    };
}
 
#ifdef _MSC_VER
#pragma warning(pop)
#endif
 
// implementation
 
#include <memory.h>
#include <stdint.h>
#include <stdio.h>
#include <time.h>
 
#include <cstring>
#include <ctime>
 
#include <iomanip>
#include <random>
#include <sstream>
#include <string>
#include <vector>
 
#include <unistd.h>
 
inline bool sole::uuid::operator==( const sole::uuid &other ) const {
    return ab == other.ab && cd == other.cd;
}
inline bool sole::uuid::operator!=( const sole::uuid &other ) const {
    return !operator==(other);
}
inline bool sole::uuid::operator<( const sole::uuid &other ) const {
    if( ab < other.ab ) return true;
    if( ab > other.ab ) return false;
    if( cd < other.cd ) return true;
    return false;
}
 
namespace sole {
 
    inline std::string uuid::str() const {
        std::stringstream ss;
        ss << std::hex << std::nouppercase << std::setfill('0');
 
        uint32_t a = (ab >> 32);
        uint32_t b = (ab & 0xFFFFFFFF);
        uint32_t c = (cd >> 32);
        uint32_t d = (cd & 0xFFFFFFFF);
 
        ss << std::setw(8) << (a) << '-';
        ss << std::setw(4) << (b >> 16) << '-';
        ss << std::setw(4) << (b & 0xFFFF) << '-';
        ss << std::setw(4) << (c >> 16 ) << '-';
        ss << std::setw(4) << (c & 0xFFFF);
        ss << std::setw(8) << d;
 
        return ss.str();
    }
 
    inline std::string uuid::base62() const {
        int base62len = 10 + 26 + 26;
        const char base62[] =
            "0123456789"
            "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
            "abcdefghijklmnopqrstuvwxyz";
        char res[24], *end = &res[24]; *(--end) = '\0';
        uint64_t rem, AB = ab, CD = cd;
        do {
            rem = CD % base62len;
            *--end = base62[int(rem)];
            CD /= base62len;
        } while (CD > 0);
        *--end = '-';
        do {
            rem = AB % base62len;
            *--end = base62[int(rem)];
            AB /= base62len;
        } while (AB > 0);
        return end;
    }
 
    // UUID implementations
 
    inline uuid uuid4() {
        static std::random_device rd;
        static std::uniform_int_distribution<uint64_t> dist(0, (uint64_t)(~0));
 
        uuid my;
 
        my.ab = dist(rd);
        my.cd = dist(rd);
 
        my.ab = (my.ab & 0xFFFFFFFFFFFF0FFFULL) | 0x0000000000004000ULL;
        my.cd = (my.cd & 0x3FFFFFFFFFFFFFFFULL) | 0x8000000000000000ULL;
 
        return my;
    }
 
    inline uuid rebuild( uint64_t ab, uint64_t cd ) {
        uuid u;
        u.ab = ab; u.cd = cd;
        return u;
    }
 
    inline uuid rebuild( const std::string &uustr ) {
        char sep;
        uint64_t a,b,c,d,e;
        uuid u = { 0, 0 };
        auto idx = uustr.find_first_of("-");
        if( idx != std::string::npos ) {
            // single separator, base62 notation
            if( uustr.find_first_of("-",idx+1) == std::string::npos ) {
                auto rebase62 = [&]( const char *input, size_t limit ) -> uint64_t {
                    int base62len = 10 + 26 + 26;
                    auto strpos = []( char ch ) -> size_t {
                        if( ch >= 'a' ) return ch - 'a' + 10 + 26;
                        if( ch >= 'A' ) return ch - 'A' + 10;
                        return ch - '0';
                    };
                    uint64_t res = strpos( input[0] );
                    for( size_t i = 1; i < limit; ++i )
                        res = base62len * res + strpos( input[i] );
                    return res;
                };
                u.ab = rebase62( &uustr[0], idx );
                u.cd = rebase62( &uustr[idx+1], uustr.size() - (idx+1) );
            }
            // else classic hex notation
            else {
                std::stringstream ss( uustr );
                if( ss >> std::hex >> a >> sep >> b >> sep >> c >> sep >> d >> sep >> e ) {
                    if( ss.eof() ) {
                        u.ab = (a << 32) | (b << 16) | c;
                        u.cd = (d << 48) | e;
                    }
                }
            }
        }
        return u;
    }
 
} // ::sole