H5DataType.h

// C++ informative line for the emacs editor: -*- C++ -*-
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// Class DataType inherits from H5Object and has several subclasses for
// specific HDF5 data types.

#ifndef __H5DataType_H
#define __H5DataType_H

namespace H5 {

class H5_DLLCPP DataType : public H5Object {
   public:
    // Creates a datatype given its class and size
    DataType( const H5T_class_t type_class, size_t size );

    // Copy constructor: makes a copy of the original object
    DataType( const DataType& original );

    // Creates a copy of a predefined type
    DataType(const PredType& pred_type);

    // Creates a datatype by way of dereference.
    DataType(const H5Location& loc, const void* ref, H5R_type_t ref_type = H5R_OBJECT);
    DataType(const Attribute& attr, const void* ref, H5R_type_t ref_type = H5R_OBJECT);

    // Closes this datatype.
    virtual void close();

    // Copies an existing datatype to this datatype object.
    void copy(const DataType& like_type);

    // Copies the datatype of dset to this datatype object.
    void copy(const DataSet& dset);

    // Returns the datatype class identifier.
    H5T_class_t getClass() const;

    // Commits a transient datatype to a file; this datatype becomes
    // a named datatype which can be accessed from the location.
    void commit(const H5Location& loc, const char* name);
    void commit(const H5Location& loc, const H5std_string& name);
    // These two overloaded functions are kept for backward compatibility
    // only; they missed the const - removed from 1.8.18 and 1.10.1
    //void commit(H5Location& loc, const char* name);
    //void commit(H5Location& loc, const H5std_string& name);

    // Determines whether this datatype is a named datatype or
    // a transient datatype.
    bool committed() const;

        // Finds a conversion function that can handle the conversion
        // this datatype to the given datatype, dest.
    H5T_conv_t find( const DataType& dest, H5T_cdata_t **pcdata ) const;

    // Converts data from between specified datatypes.
    void convert( const DataType& dest, size_t nelmts, void *buf, void *background, const PropList& plist=PropList::DEFAULT) const;

    // Assignment operator
    DataType& operator=( const DataType& rhs );

    // Determines whether two datatypes are the same.
    bool operator==(const DataType& compared_type ) const;

    // Locks a datatype.
    void lock() const;

    // Returns the size of a datatype.
    size_t getSize() const;

    // Returns the base datatype from which a datatype is derived.
    // Note: not quite right for specific types yet???
    DataType getSuper() const;

    // Registers a conversion function.
    void registerFunc(H5T_pers_t pers, const char* name, const DataType& dest, H5T_conv_t func ) const;
    void registerFunc(H5T_pers_t pers, const H5std_string& name, const DataType& dest, H5T_conv_t func ) const;

    // Removes a conversion function from all conversion paths.
    void unregister( H5T_pers_t pers, const char* name, const DataType& dest, H5T_conv_t func ) const;
    void unregister( H5T_pers_t pers, const H5std_string& name, const DataType& dest, H5T_conv_t func ) const;

    // Tags an opaque datatype.
    void setTag( const char* tag ) const;
    void setTag( const H5std_string& tag ) const;

    // Gets the tag associated with an opaque datatype.
    H5std_string getTag() const;

    // Checks whether this datatype contains (or is) a certain type class.
    bool detectClass(H5T_class_t cls) const;

    // Checks whether this datatype is a variable-length string.
    bool isVariableStr() const;

    virtual H5std_string fromClass () const { return("DataType"); }

    // Creates a copy of an existing DataType using its id
    DataType( const hid_t type_id );

    // Default constructor
    DataType();

    // Gets the datatype id.
    virtual hid_t getId() const;

    // Destructor: properly terminates access to this datatype.
    virtual ~DataType();

   protected:
#ifndef DOXYGEN_SHOULD_SKIP_THIS
    hid_t id;   // HDF5 datatype id

    // Sets the datatype id.
    virtual void p_setId(const hid_t new_id);
#endif // DOXYGEN_SHOULD_SKIP_THIS

   private:
    // Friend function to set DataType id.  For library use only.
    friend void f_DataType_setId(DataType* dtype, hid_t new_id);

    void p_commit(hid_t loc_id, const char* name);
};
}
#endif // __H5DataType_H