UT_Hash.h

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/*
 * PROPRIETARY INFORMATION.  This software is proprietary to
 * Side Effects Software Inc., and is not to be reproduced,
 * transmitted, or disclosed in any way without written permission.
 *
 * NAME:        UT_Hash.h ( UT Library, C++)
 *
 * COMMENTS:
 */

#ifndef __UT_Hash__
#define __UT_Hash__

#include "UT_API.h"
#include <string.h>
#include <stdlib.h>
#include <malloc.h>

#include <SYS/SYS_Deprecated.h>
#include <SYS/SYS_Math.h>
#include "UT_String.h"
#include "UT_SmallObject.h"

SYS_DEPRECATED_PUSH_DISABLE()

class SYS_DEPRECATED_REPLACE(16.0, "SYShash") UT_API UT_Hash
#if !SYS_IS_GCC_GE(4,7)
    : public UT_SmallObject<UT_Hash,
                            UT_SMALLOBJECT_CLEANPAGES_DEFAULT,
                            UT_SMALLOBJECT_PAGESIZE_DEFAULT,
                            UT_SMALLOBJECT_THREADSAFE_ON>
#endif // GCC 4.7+ crashes in some cases with UT_Hash as a small object.
{
    public:
        UT_Hash() = default;
        virtual ~UT_Hash() = default;

        UT_Hash(const UT_Hash &) = delete;
        UT_Hash &operator=(const UT_Hash &) = delete;

        // return 0 on equality
        //
        // Often, the comparison function for a UT_Hash is more expensive
        // than computing the unsigned integer hash code.  However, it's
        // possible for the compare() function to be called even when
        // there is no collision on the hash codes, therefore, if you
        // have the hash codes cached, its often efficient to do
        // a quick comparison of the hash codes before computing the
        // expensive compare function.
        virtual int             compare(const UT_Hash &a) const = 0;

        // Copies data from another UT_Hash into this one.
        virtual void            copy(const UT_Hash &a) = 0;

        // return hash value
        // should never change i.e. should rely on const data
        virtual unsigned        hash() const = 0;

        virtual UT_Hash*        copy() const = 0;

        virtual int64           getMemoryUsage(bool inclusive) const = 0;
};

class SYS_DEPRECATED_REPLACE(16.0, "SYShash<string>") UT_API UT_Hash_String : 
    public UT_Hash 
{
    private:
        char            *myData;
    public:
        UT_Hash_String( const char *s )
        {
            myData = strdup( s );
        }

        ~UT_Hash_String() override
        {
            free(myData);
        }

        int                     compare( const UT_Hash & a) const override
        {
            return strcmp(myData, ((const UT_Hash_String&)a).myData);
        }

        void                    copy(const UT_Hash &a) override
        {
            free(myData);
            myData = strdup(static_cast<const UT_Hash_String &>(a).myData);
        }

        unsigned                hash() const override
        {
            return UT_String::hash(myData);
        }

        UT_Hash*                copy() const override
        {
            return new UT_Hash_String( myData );
        }

        int64                   getMemoryUsage(bool inclusive) const override
        {
            return (inclusive ? sizeof(*this) : 0)
                + (::strlen(myData) + 1) * sizeof(char);
        }

        const char*     getString() const
        {
            return myData;
        }
};

class SYS_DEPRECATED_REPLACE(16.0, "SYShash<int>") UT_API UT_Hash_Int : 
    public UT_Hash {
    private:
        int                     myData;
        unsigned                myKey;
    public:
        UT_Hash_Int( int a ) : myData( a )
        {
            myKey = (unsigned) a;
            myKey = SYSwang_inthash(myKey);
        }

        ~UT_Hash_Int() override
        {
        }

        int                     compare( const UT_Hash & a) const override
        {
            return !(myData==((const UT_Hash_Int&)a).myData);
        }

        void                    copy(const UT_Hash &a) override
        {
            myData = static_cast<const UT_Hash_Int &>(a).myData;
            myKey = static_cast<const UT_Hash_Int &>(a).myKey;
        }

        unsigned                hash() const override
        {
            return myKey;
        }

        UT_Hash*                copy() const override
        {
            return new UT_Hash_Int( myData );
        }

        int64                   getMemoryUsage(bool inclusive) const override
        {
            return inclusive ? sizeof(*this) : 0;
        }

        int             getData() const { return myData; }
};

class SYS_DEPRECATED_REPLACE(16.0, "SYShash<int64>") UT_API UT_Hash_Int64 : public UT_Hash {
    private:
        int64                   myData;
        uint64                  myKey;
    public:
        UT_Hash_Int64( int64 a ) : myData( a )
        {
            myKey = (uint64) a;
            myKey = SYSwang_inthash64(myKey);
        }

        ~UT_Hash_Int64() override
        {
        }

        int                     compare( const UT_Hash & a) const override
        {
            return !(myData==((const UT_Hash_Int64&)a).myData);
        }

        void                    copy(const UT_Hash &a) override
        {
            myData = static_cast<const UT_Hash_Int64 &>(a).myData;
            myKey = static_cast<const UT_Hash_Int64 &>(a).myKey;
        }

        unsigned                hash() const override
        {
            return myKey;
        }

        UT_Hash*                copy() const override
        {
            return new UT_Hash_Int64( myData );
        }

        int64                   getMemoryUsage(bool inclusive) const override
        {
            return inclusive ? sizeof(*this) : 0;
        }

        int64           getData() const { return myData; }
};

class SYS_DEPRECATED_REPLACE(16.0, "SYShash<void *>") UT_API UT_Hash_Ptr : public UT_Hash {
    private:
        const void      *myData;
    public:
        UT_Hash_Ptr( const void *p )
            : myData(p)
        {
        }

        ~UT_Hash_Ptr() override
        {
        }

        int                     compare(const UT_Hash &a) const override
        {
            return !(myData==((const UT_Hash_Ptr&)a).myData);
        }

        void                    copy(const UT_Hash &a) override
        {
            myData = static_cast<const UT_Hash_Ptr &>(a).myData;
        }

        unsigned                hash() const override
        {
            unsigned            key;
            key = SYSpointerHash(myData);
            key = SYSwang_inthash(key);
            return key;
        }

        UT_Hash*                copy() const override
        {
            return new UT_Hash_Ptr(myData);
        }

        int64                   getMemoryUsage(bool inclusive) const override
        {
            return inclusive ? sizeof(*this) : 0;
        }

        /// Get the pointer as a given type
        template <typename T>
            const T     *asPointer() const { return (const T *)(myData); }

        /// Casting operators
        operator const void *() const
        {
            return myData;
        }
        operator void *() const
        {
            return const_cast<void *>(myData);
        }
};

class SYS_DEPRECATED_REPLACE(16.0, "SYShash<const void *>") UT_API 
    UT_Hash_Const_Ptr : public UT_Hash {
    private:
        const void  *myData;
    public:
        UT_Hash_Const_Ptr( const void *p ) : myData(p)
        {
        }

        ~UT_Hash_Const_Ptr() override
        {
        }

        int                     compare(const UT_Hash &a) const override
        {
            return !(myData==((const UT_Hash_Const_Ptr&)a).myData);
        }

        void                    copy(const UT_Hash &a) override
        {
            myData = static_cast<const UT_Hash_Const_Ptr &>(a).myData;
        }

        unsigned                hash() const override
        {
            unsigned            key;
            key = SYSpointerHash(myData);
            key = SYSwang_inthash(key);
            return key;
        }

        UT_Hash*                copy() const override
        {
            return new UT_Hash_Const_Ptr(myData);
        }

        int64                   getMemoryUsage(bool inclusive) const override
        {
            return inclusive ? sizeof(*this) : 0;
        }
};

SYS_DEPRECATED_POP_DISABLE()

#endif