H5Location.h

// C++ informative line for the emacs editor: -*- C++ -*-
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
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#ifndef __H5Location_H
#define __H5Location_H

#include "H5Classes.h"      // constains forward class declarations

namespace H5 {

class H5_DLLCPP H5Location;  // forward declaration for UserData4Aiterate

// Define the operator function pointer for H5Aiterate().
typedef void (*attr_operator_t)( H5Location& loc/*in*/,
                                 const H5std_string attr_name/*in*/,
                                 void *operator_data/*in,out*/);

class UserData4Aiterate { // user data for attribute iteration
   public:
    attr_operator_t op;
    void* opData;
    H5Location* location;
};

// Most of these methods were in H5Object but are now moved here because
// a location can be a file, group, dataset, or named datatype. -BMR, 2013-10-1
class H5_DLLCPP H5Location : public IdComponent {
   public:
    // Creates an attribute for the specified object at this location
    // PropList is currently not used, so always be default.
    Attribute createAttribute( const char* name, const DataType& type, const DataSpace& space, const PropList& create_plist = PropList::DEFAULT ) const;
    Attribute createAttribute( const H5std_string& name, const DataType& type, const DataSpace& space, const PropList& create_plist = PropList::DEFAULT ) const;

    // Given its name, opens the attribute that belongs to an object at
    // this location.
    Attribute openAttribute( const char* name ) const;
    Attribute openAttribute( const H5std_string& name ) const;

    // Given its index, opens the attribute that belongs to an object at
    // this location.
    Attribute openAttribute( const unsigned int idx ) const;

    // Flushes all buffers associated with this location to disk.
    void flush( H5F_scope_t scope ) const;

    // Gets the name of the file, specified by this location.
    H5std_string getFileName() const;

    // Determines the number of attributes at this location.
    int getNumAttrs() const;

#ifndef H5_NO_DEPRECATED_SYMBOLS
    // Retrieves the type of object that an object reference points to.
    H5G_obj_t getObjType(void *ref, H5R_type_t ref_type = H5R_OBJECT) const;
#endif /* H5_NO_DEPRECATED_SYMBOLS */

    // Retrieves the type of object that an object reference points to.
    H5O_type_t getRefObjType(void *ref, H5R_type_t ref_type = H5R_OBJECT) const;
    // Note: getRefObjType deprecates getObjType, but getObjType's name is
    // misleading, so getRefObjType is used in the new function instead.

    // Iterate user's function over the attributes at this location.
    int iterateAttrs(attr_operator_t user_op, unsigned* idx = NULL, void* op_data = NULL);

    // Checks whether the named attribute exists at this location.
    bool attrExists(const char* name) const;
    bool attrExists(const H5std_string& name) const;

    // Renames the named attribute to a new name.
    void renameAttr(const char* oldname, const char* newname) const;
    void renameAttr(const H5std_string& oldname, const H5std_string& newname) const;

    // Removes the named attribute from this location.
    void removeAttr(const char* name) const;
    void removeAttr(const H5std_string& name) const;

    // Sets the comment for an HDF5 object specified by its name.
    void setComment(const char* name, const char* comment) const;
    void setComment(const H5std_string& name, const H5std_string& comment) const;
    void setComment(const char* comment) const;
    void setComment(const H5std_string& comment) const;

    // Retrieves comment for the HDF5 object specified by its name.
    ssize_t getComment(const char* name, size_t buf_size, char* comment) const;
    H5std_string getComment(const char* name, size_t buf_size=0) const;
    H5std_string getComment(const H5std_string& name, size_t buf_size=0) const;

    // Removes the comment for the HDF5 object specified by its name.
    void removeComment(const char* name) const;
    void removeComment(const H5std_string& name) const;

    // Creates a reference to a named object or to a dataset region
    // in this object.
    void reference(void* ref, const char* name, 
            H5R_type_t ref_type = H5R_OBJECT) const;
    void reference(void* ref, const H5std_string& name, 
            H5R_type_t ref_type = H5R_OBJECT) const;
    void reference(void* ref, const char* name, const DataSpace& dataspace,
            H5R_type_t ref_type = H5R_DATASET_REGION) const;
    void reference(void* ref, const H5std_string& name, const DataSpace& dataspace,
            H5R_type_t ref_type = H5R_DATASET_REGION) const;

    // Open a referenced object whose location is specified by either
    // a file, an HDF5 object, or an attribute.
    void dereference(const H5Location& loc, const void* ref, H5R_type_t ref_type = H5R_OBJECT);
    void dereference(const Attribute& attr, const void* ref, H5R_type_t ref_type = H5R_OBJECT);

    // Retrieves a dataspace with the region pointed to selected.
    DataSpace getRegion(void *ref, H5R_type_t ref_type = H5R_DATASET_REGION) const;

    virtual hid_t getId() const = 0;

   protected:
#ifndef DOXYGEN_SHOULD_SKIP_THIS
    // Default constructor,
    H5Location();

    // *** Deprecation warning ***
    // The following two constructors are no longer appropriate after the
    // data member "id" had been moved to the sub-classes.
    // The copy constructor is a noop and is removed in 1.8.15 and the
    // other will be removed from 1.10 release, and then from 1.8 if its
    // removal does not raise any problems in two 1.10 releases.

    // Creates a copy of an existing object giving the location id.
    H5Location(const hid_t loc_id);

    // Creates a reference to an HDF5 object or a dataset region.
    void p_reference(void* ref, const char* name, hid_t space_id, H5R_type_t ref_type) const;

    // Dereferences a ref into an HDF5 id.
    hid_t p_dereference(hid_t loc_id, const void* ref, H5R_type_t ref_type, const char* from_func);

#ifndef H5_NO_DEPRECATED_SYMBOLS
    // Retrieves the type of object that an object reference points to.
    H5G_obj_t p_get_obj_type(void *ref, H5R_type_t ref_type) const;
#endif /* H5_NO_DEPRECATED_SYMBOLS */

    // Retrieves the type of object that an object reference points to.
    H5O_type_t p_get_ref_obj_type(void *ref, H5R_type_t ref_type) const;

        // Sets the identifier of this object to a new value. - this one
        // doesn't increment reference count
        virtual void p_setId(const hid_t new_id) = 0;

#endif // DOXYGEN_SHOULD_SKIP_THIS

    // Noop destructor.
    virtual ~H5Location();

}; /* end class H5Location */

}
#endif // __H5Location_H