/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Copyright by The HDF Group. *
* Copyright by the Board of Trustees of the University of Illinois. *
* All rights reserved. *
* *
* This file is part of HDF5. The full HDF5 copyright notice, including *
* terms governing use, modification, and redistribution, is contained in *
* the COPYING file, which can be found at the root of the source code *
* distribution tree, or in https://www.hdfgroup.org/licenses. *
* If you do not have access to either file, you may request a copy from *
* help@hdfgroup.org. *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*
* This file contains public declarations for the H5R module.
*/
#ifndef H5Rpublic_H
#define H5Rpublic_H
/* Public headers needed by this file */
#include "H5public.h"
#include "H5Gpublic.h"
#include "H5Ipublic.h"
/*****************/
/* Public Macros */
/*****************/
/* Deprecated reference buffer sizes that are kept for backward compatibility */
#define H5R_OBJ_REF_BUF_SIZE sizeof(haddr_t)
#define H5R_DSET_REG_REF_BUF_SIZE (sizeof(haddr_t) + 4)
/**
* Default reference buffer size.
*
* \internal Note! Be careful with the sizes of the references because they
* should really depend on the run-time values in the file.
*/
#define H5R_REF_BUF_SIZE (64)
/*******************/
/* Public Typedefs */
/*******************/
//! <!-- [H5R_type_t_snip] -->
/**
* Reference types allowed.
*
* \internal DO NOT CHANGE THE ORDER or VALUES as reference type values are
* encoded into the datatype message header.
*/
typedef enum {
H5R_BADTYPE = (-1), /**< Invalid reference type */
H5R_OBJECT1 = 0, /**< Backward compatibility (object) */
H5R_DATASET_REGION1 = 1, /**< Backward compatibility (region) */
H5R_OBJECT2 = 2, /**< Object reference */
H5R_DATASET_REGION2 = 3, /**< Region reference */
H5R_ATTR = 4, /**< Attribute Reference */
H5R_MAXTYPE = 5 /**< Highest type (invalid) */
} H5R_type_t;
//! <!-- [H5R_type_t_snip] -->
/* Deprecated types are kept for backward compatibility with previous versions */
//! <!-- [hobj_ref_t_snip] -->
/**
* \deprecated Deprecated object reference type that is used with deprecated
* reference APIs.
*
* \note This type can only be used with the "native" HDF5 VOL connector.
*/
typedef haddr_t hobj_ref_t;
//! <!-- [hobj_ref_t_snip] -->
//! <!-- [hdset_reg_ref_t_snip] -->
/**
* Buffer to store heap ID and index
*
* This needs to be large enough to store largest #haddr_t in a worst case
* machine (8 bytes currently) plus an int.
*
* \deprecated Dataset region reference type that is used with deprecated
* reference APIs.
*
* \note This type can only be used with the "native" HDF5 VOL connector.
*/
typedef struct {
uint8_t __data[H5R_DSET_REG_REF_BUF_SIZE];
} hdset_reg_ref_t;
//! <!-- [hdset_reg_ref_t_snip] -->
//! <!-- [H5R_ref_t_snip] -->
/**
* Opaque reference type. The same reference type is used for object,
* dataset region and attribute references. This is the type that
* should always be used with the current reference API.
*/
typedef struct {
union {
uint8_t __data[H5R_REF_BUF_SIZE]; /**< opaque data */
int64_t align; /**< ensures alignment */
} u;
} H5R_ref_t;
//! <!-- [H5R_ref_t_snip] -->
/********************/
/* Public Variables */
/********************/
/*********************/
/* Public Prototypes */
/*********************/
#ifdef __cplusplus
extern "C" {
#endif
/* Constructors */
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Creates an object reference
*
* \fgdta_loc_id
* \param[in] name Name of object
* \oapl_id
* \param[out] ref_ptr Pointer to reference
*
* \return \herr_t
*
* \details H5Rcreate_object() creates a reference pointing to the
* object named \p name located at \p loc_id. The parameters \p
* loc_id and \p name are used to locate the object.
*
* The parameter \p oapl_id is an object access property list
* identifier for the referenced object. The access property list
* must be of the same type as the object being referenced, that is
* a group, dataset or committed datatype property list.
*
* \ref H5R_ref_t is defined in H5Rpublic.h as:
* \snippet this H5R_ref_t_snip
*
* H5Rdestroy() should be used to release the resource from the
* reference.
*
*/
H5_DLL herr_t H5Rcreate_object(hid_t loc_id, const char *name, hid_t oapl_id, H5R_ref_t *ref_ptr);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Creates a region reference
*
* \fgdta_loc_id
* \param[in] name Name of object
* \space_id
* \oapl_id
* \param[out] ref_ptr Pointer to reference
*
* \return \herr_t
*
* \details H5Rcreate_region() creates the reference, \p ref_ptr,
* pointing to the region represented by \p space_id within the
* object named name located at \p loc_id.
*
* The parameters \p loc_id and \p name are used to locate the
* object. The parameter \p space_id identifies the dataset region
* that a dataset region reference points to.
*
* The parameter \p oapl_id is an object access property list
* identifier for the referenced object. The access property list
* must be of the same type as the object being referenced, that is
* a dataset property list in this case.
*
* \ref H5R_ref_t is defined in H5Rpublic.h as:
* \snippet this H5R_ref_t_snip
*
* H5Rdestroy() should be used to release the resource from the
* reference.
*
*/
H5_DLL herr_t H5Rcreate_region(hid_t loc_id, const char *name, hid_t space_id, hid_t oapl_id,
H5R_ref_t *ref_ptr);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Creates an attribute reference
*
* \fgdta_loc_id
* \param[in] name Name of object
* \param[in] attr_name Name of attribute
* \oapl_id
* \param[out] ref_ptr Pointer to reference
*
* \return \herr_t
*
* \details H5Rcreate_attr() creates the reference, \p ref_ptr, pointing
* to the attribute named \p attr_name and attached to the object
* named \p name located at \p loc_id.
*
* The parameters \p loc_id and \p name locate the object. The
* parameter \p attr_name specifies the attribute within the object.
*
* The parameter \p oapl_id is an object access property list
* identifier for the object that the referenced attribute is
* attached to. The access property list must be of the same type
* as that object, that is a group, dataset or committed datatype
* property list.
*
* \ref H5R_ref_t is defined in H5Rpublic.h as:
* \snippet this H5R_ref_t_snip
*
* H5Rdestroy() should be used to release the resource from the
* reference.
*
*/
H5_DLL herr_t H5Rcreate_attr(hid_t loc_id, const char *name, const char *attr_name, hid_t oapl_id,
H5R_ref_t *ref_ptr);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Closes a reference
*
* \param[in] ref_ptr Pointer to reference
*
* \return \herr_t
*
* \details Given a reference, \p ref_ptr, to an object, region or attribute
* attached to an object, H5Rdestroy() releases allocated resources
* from a previous create call.
*
* \ref H5R_ref_t is defined in H5Rpublic.h as:
* \snippet this H5R_ref_t_snip
*
*/
H5_DLL herr_t H5Rdestroy(H5R_ref_t *ref_ptr);
/* Info */
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves the type of a reference
*
* \param[in] ref_ptr Pointer to reference
*
* \return Returns a valid reference type if successful; otherwise returns #H5R_BADTYPE .
*
* \details Given a reference, \p ref_ptr, H5Rget_type() returns the
* type of the reference.
*
* Valid returned reference types are:
* \snippet this H5R_type_t_snip
*
* Note that #H5R_OBJECT1 and #H5R_DATASET_REGION1 can never be
* associated to an \ref H5R_ref_t reference and can therefore never be
* returned through that function.
*
* \ref H5R_ref_t is defined in H5Rpublic.h as:
* \snippet this H5R_ref_t_snip
*
*/
H5_DLL H5R_type_t H5Rget_type(const H5R_ref_t *ref_ptr);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Determines whether two references are equal
*
* \param[in] ref1_ptr Pointer to reference to compare
* \param[in] ref2_ptr Pointer to reference to compare
*
* \return Returns a positive value if the references are equal. Returns
* 0 if the references are not equal. Returns a negative value when the
* function fails.
*
* \details H5Requal() determines whether two references point to the
* same object, region or attribute.
*
* \ref H5R_ref_t is defined in H5Rpublic.h as:
* \snippet this H5R_ref_t_snip
*
*/
H5_DLL htri_t H5Requal(const H5R_ref_t *ref1_ptr, const H5R_ref_t *ref2_ptr);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Copies an existing reference
*
* \param[in] src_ref_ptr Pointer to reference to copy
* \param[out] dst_ref_ptr Pointer to output reference
*
* \return \herr_t
*
* \details H5Rcopy() creates a copy of an existing reference.
* \p src_ref_ptr points to the reference to copy and \p dst_ref_ptr is the
* pointer to the destination reference.
*
*/
H5_DLL herr_t H5Rcopy(const H5R_ref_t *src_ref_ptr, H5R_ref_t *dst_ref_ptr);
/* Dereference */
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Opens the HDF5 object referenced
*
* \param[in] ref_ptr Pointer to reference to open
* \rapl_id
* \oapl_id
*
* \return \hid_t{object}
*
* \details Given a reference, \p ref_ptr, to an object, a region in
* an object, or an attribute attached to an object, H5Ropen_object()
* opens that object and returns an identifier.
*
* The parameter \p oapl_id is an object access property list
* identifier for the referenced object. The access property list
* must be of the same type as the object being referenced, that is
* a group or dataset property list.
*
* \ref H5R_ref_t is defined in H5Rpublic.h as:
* \snippet this H5R_ref_t_snip
*
* The object opened with this function should be closed when it
* is no longer needed so that resource leaks will not develop. Use
* the appropriate close function such as H5Oclose() or H5Dclose()
* for datasets.
*
*/
H5_DLL hid_t H5Ropen_object(H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id);
/**
* --------------------------------------------------------------------------
* \ingroup ASYNC
* \async_variant_of{H5Ropen}
*/
H5_DLL hid_t H5Ropen_object_async(const char *app_file, const char *app_func, unsigned app_line,
H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id, hid_t es_id);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Sets up a dataspace and selection as specified by a region reference.
*
* \param[in] ref_ptr Pointer to reference to open
* \rapl_id
* \oapl_id
*
* \return \hid_t{dataspace}
*
* \details H5Ropen_region() creates a copy of the dataspace of the
* dataset pointed to by a region reference, \p ref_ptr, and defines
* a selection matching the selection pointed to by \p ref_ptr within
* the dataspace copy.
*
* The parameter \p rapl id is a reference access property list
* identifier for the reference. The access property list can
* be used to access external files that the reference points to
* (through a file access property list).
*
* The parameter \p oapl id is an object access property list
* identifier for the referenced object. The access property list
* must be of the same type as the object being referenced, that is
* a dataset property list in that case.
*
* Use H5Sclose() to release the dataspace identifier returned by
* this function when the identifier is no longer needed.
*
*/
H5_DLL hid_t H5Ropen_region(H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id);
/**
* --------------------------------------------------------------------------
* \ingroup ASYNC
* \async_variant_of{H5Ropen_region}
*/
H5_DLL hid_t H5Ropen_region_async(const char *app_file, const char *app_func, unsigned app_line,
H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t oapl_id, hid_t es_id);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Opens the HDF5 attribute referenced
*
* \param[in] ref_ptr Pointer to reference to open
* \rapl_id
* \aapl_id
*
* \return \hid_t{attribute}
*
* \details Given a reference, \p ref_ptr, to an attribute attached to
* an object, H5Ropen_attr() opens the attribute attached to that
* object and returns an identifier.
*
* The parameter \p rapl id is a reference access property list
* identifier for the reference. The access property list can
* be used to access external files that the reference points to
* (through a file access property list).
*
* The parameter \p aapl_id is an attribute access property list
* identifier for the referenced attribute.
*
* The attribute opened with this function should be closed with
* H5Aclose() when it is no longer needed.
*
*/
H5_DLL hid_t H5Ropen_attr(H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t aapl_id);
/**
* --------------------------------------------------------------------------
* \ingroup ASYNC
* \async_variant_of{H5Ropen_attr}
*/
H5_DLL hid_t H5Ropen_attr_async(const char *app_file, const char *app_func, unsigned app_line,
H5R_ref_t *ref_ptr, hid_t rapl_id, hid_t aapl_id, hid_t es_id);
/* Get type */
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves the type of object that an object reference points to
*
* \param[in] ref_ptr Pointer to reference to query
* \rapl_id
* \param[out] obj_type Type of referenced object
*
* \return \herr_t
*
* \details Given a reference, \p ref_ptr, H5Rget_obj_type3() retrieves
* the type of the referenced object in \p obj_type.
*
* The parameter \p rapl id is a reference access property list
* identifier for the reference. The access property list can
* be used to access external files that the reference points to
* (through a file access property list).
*
* Upon success, the function returns in \p obj_type the type of
* the object that the reference points to. Valid values for this
* referenced object type are as followed (defined in H5Opublic.h):
* \snippet H5Opublic.h H5O_type_t_snip
*
*/
H5_DLL herr_t H5Rget_obj_type3(H5R_ref_t *ref_ptr, hid_t rapl_id, H5O_type_t *obj_type);
/* Get name */
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves the file name for a referenced object
*
* \param[in] ref_ptr Pointer to reference to query
* \param[in,out] name Buffer to place the file name of the reference
* \param[in] size Size of the \p name buffer
*
* \return Returns the length of the name if successful, otherwise, a negative value.
*
* \details H5Rget_file_name() retrieves the file name for the object,
* region or attribute reference pointed to by \p ref_ptr.
*
* Up to \p size characters of the name are returned in \p name;
* additional characters, if any, are not returned to the user
* application. If the length of the name, which determines
* the required value of size, is unknown, a preliminary
* H5Rget_file_name() call can be made. The return value of this
* call will be the size of the file name. That value can then be
* passed in for size in the second call to H5Rget_file_name(),
* which will retrieve the actual name.
*
*/
H5_DLL ssize_t H5Rget_file_name(const H5R_ref_t *ref_ptr, char *name, size_t size);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves the object name for a referenced object
*
* \param[in] ref_ptr Pointer to reference to query
* \rapl_id
* \param[in,out] name Buffer to place the file name of the reference
* \param[in] size Size of the \p name buffer
*
* \return Returns the length of the name if successful, returning
* 0 (zero) if no name is associated with the identifier. Otherwise
* returns a negative value.
*
* \details H5Rget_obj_name() retrieves the object name for the object,
* region or attribute reference pointed to by \p ref_ptr.
*
* The parameter \p rapl_id is a reference access property list
* identifier for the reference. The access property list can
* be used to access external files that the reference points to
* (through a file access property list).
*
* Up to size characters of the name are returned in \p name; additional
* characters, if any, are not returned to the user application. If
* the length of the name, which determines the required value of
* \p size, is unknown, a preliminary call to H5Rget_obj_name() call
* can be made. The return value of this call will be the size of the
* object name. That value can then be passed in for \p size in the
* second call to H5Rget_obj_name(), which will retrieve the actual
* name. If there is no name associated with the object identifier
* or if the name is NULL, H5Rget_obj_name() returns the size of
* the name buffer (the size does not include the \c \0 terminator).
*
* If \p ref_ptr is an object reference, \p name will be returned with
* a name for the referenced object. If \p ref_ptr is a dataset region
* reference, \p name will contain a name for the object containing
* the referenced region. If \p ref_ptr is an attribute reference, \p
* name will contain a name for the object the attribute is attached
* to. Note that an object in an HDF5 file may have multiple paths
* if there are multiple links pointing to it. This function may
* return any one of these paths.
*
*/
H5_DLL ssize_t H5Rget_obj_name(H5R_ref_t *ref_ptr, hid_t rapl_id, char *name, size_t size);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves the attribute name for a referenced object
*
* \param[in] ref_ptr Pointer to reference to query
* \param[in,out] name Buffer to place the attribute name of the reference
* \param[in] size Size of the \p name buffer
*
* \return Returns the length of the name if successful, otherwise, a negative value.
*
* \details H5Rget_attr_name() retrieves the attribute name for the
* attribute reference pointed to by \p ref_ptr.
*
* Up to size characters of the name are returned in \p name;
* additional characters, if any, are not returned to the user
* application. If the length of the name, which determines
* the required value of \p size, is unknown, a preliminary
* H5Rget_attr_name() call can be made. The return value of this
* call will be the size of the attribute name. That value can then
* be passed in for size in the second call to H5Rget_attr_name(),
* which will retrieve the actual name.
*
*/
H5_DLL ssize_t H5Rget_attr_name(const H5R_ref_t *ref_ptr, char *name, size_t size);
/// \cond DEV
/* API Wrappers for async routines */
/* (Must be defined _after_ the function prototype) */
/* (And must only defined when included in application code, not the library) */
#ifndef H5R_MODULE
#define H5Ropen_object_async(...) H5Ropen_object_async(__FILE__, __func__, __LINE__, __VA_ARGS__)
#define H5Ropen_region_async(...) H5Ropen_region_async(__FILE__, __func__, __LINE__, __VA_ARGS__)
#define H5Ropen_attr_async(...) H5Ropen_attr_async(__FILE__, __func__, __LINE__, __VA_ARGS__)
/* Define "wrapper" versions of function calls, to allow compile-time values to
* be passed in by language wrapper or library layer on top of HDF5. */
#define H5Ropen_object_async_wrap H5_NO_EXPAND(H5Ropen_object_async)
#define H5Ropen_region_async_wrap H5_NO_EXPAND(H5Ropen_region_async)
#define H5Ropen_attr_async_wrap H5_NO_EXPAND(H5Ropen_attr_async)
#endif /* H5R_MODULE */
/// \endcond
/* Symbols defined for compatibility with previous versions of the HDF5 API.
*
* Use of these symbols is or will be deprecated.
*/
/* Macros */
/* Versions for compatibility */
#define H5R_OBJECT H5R_OBJECT1
#define H5R_DATASET_REGION H5R_DATASET_REGION1
/* Function prototypes */
#ifndef H5_NO_DEPRECATED_SYMBOLS
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves the type of object that an object reference points to
*
* \param[in] id The dataset containing the reference object or the group
* containing that dataset
* \param[in] ref_type Type of reference to query
* \param[in] ref Reference to query
*
* \return Returns a valid object type if successful; otherwise returns a
* negative value (#H5G_UNKNOWN).
*
* \deprecated This function has been renamed from H5Rget_obj_type() and is
* deprecated in favor of the macro H5Rget_obj_type() or the
* function H5Rget_obj_type2().
*
* \details Given an object reference, \p ref, H5Rget_obj_type1() returns the
* type of the referenced object.
*
* A \Emph{reference type} is the type of reference, either an object
* reference or a dataset region reference. An \Emph{object reference}
* points to an HDF5 object while a \Emph{dataset region reference}
* points to a defined region within a dataset.
*
* The \Emph{referenced object} is the object the reference points
* to. The \Emph{referenced object type}, or the type of the referenced
* object, is the type of the object that the reference points to.
*
* The location identifier, \p id, is the identifier for either the
* dataset containing the object reference or the group containing that
* dataset.
*
* Valid reference types, to pass in as \p ref_type, include the
* following:
* \snippet this H5R_type_t_snip
*
* If the application does not already know the object reference type,
* that can be determined with three preliminary calls:
*
* \li Call H5Dget_type() on the dataset containing the reference to
* get a datatype identifier for the dataset’s datatype.
* \li Using that datatype identifier, H5Tget_class() returns a datatype
* class.\n If the datatype class is #H5T_REFERENCE, H5Tequal() can
* then be used to determine whether the reference’s datatype is
* #H5T_STD_REF_OBJ or #H5T_STD_REF_DSETREG:
* - If the datatype is #H5T_STD_REF_OBJ, the reference object type
* is #H5R_OBJECT.
* - If the datatype is #H5T_STD_REF_DSETREG, the reference object
* type is #H5R_DATASET_REGION.
*
* When the function completes successfully, it returns one of the
* following valid object type values (defined in H5Gpublic.h):
* \snippet H5Gpublic.h H5G_obj_t_snip
*
* \version 1.8.0 Function H5Rget_obj_type() renamed to H5Rget_obj_type1() and
* deprecated in this release.
* \since 1.6.0
*
*/
H5_DLL H5G_obj_t H5Rget_obj_type1(hid_t id, H5R_type_t ref_type, const void *ref);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Opens the HDF5 object referenced
*
* \obj_id
* \param[in] ref_type The reference type of \p ref
* \param[in] ref Reference to open
*
* \return Returns identifier of referenced object if successful; otherwise
* returns a negative value.
*
* \deprecated This function has been renamed from H5Rdereference() and is
* deprecated in favor of the macro H5Rdereference() or the function
* H5Rdereference2().
*
* \details Given a reference, \p ref, to an object or a region in an object,
* H5Rdereference1() opens that object and returns an identifier.
*
* The parameter \p obj_id must be a valid identifier for an object in
* the HDF5 file containing the referenced object, including the file
* identifier.
*
* The parameter \p ref_type specifies the reference type of the
* reference \p ref. \p ref_type may contain either of the following
* values:
* - #H5R_OBJECT
* - #H5R_DATASET_REGION
*
* The object opened with this function should be closed when it is no
* longer needed so that resource leaks will not develop. Use the
* appropriate close function such as H5Oclose() or H5Dclose() for
* datasets.
*
* \version 1.10.0 Function H5Rdereference() renamed to H5Rdereference1() and
* deprecated in this release.
* \since 1.8.0
*
*/
H5_DLL hid_t H5Rdereference1(hid_t obj_id, H5R_type_t ref_type, const void *ref);
#endif /* H5_NO_DEPRECATED_SYMBOLS */
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Creates a reference
*
* \param[out] ref Reference created by the function call
* \param[in] loc_id Location identifier used to locate the object being pointed to
* \param[in] name Name of object at location \p loc_id
* \param[in] ref_type Type of reference
* \param[in] space_id Dataspace identifier with selection. Used only for
* dataset region references; pass as -1 if reference is
* an object reference, i.e., of type #H5R_OBJECT
*
* \return \herr_t
*
* \details H5Rcreate() creates the reference, \p ref, of the type specified in
* \p ref_type, pointing to the object \p name located at \p loc_id.
*
* The HDF5 library maps the void type specified above for \p ref to
* the type specified in \p ref_type, which will be one of the following:
* \snippet this H5R_type_t_snip
*
* The parameters \p loc_id and \p name are used to locate the object.
*
* The parameter \p space_id identifies the dataset region that a
* dataset region reference points to. This parameter is used only with
* dataset region references and should be set to -1 if the reference
* is an object reference, #H5R_OBJECT.
*
* \since 1.8.0
*/
H5_DLL herr_t H5Rcreate(void *ref, hid_t loc_id, const char *name, H5R_type_t ref_type, hid_t space_id);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves the type of object that an object reference points to
*
* \param[in] id The dataset containing the reference object or the group
* containing that dataset
* \param[in] ref_type Type of reference to query
* \param[in] ref Reference to query
* \param[out] obj_type Type of referenced object
*
* \return \herr_t
*
* \details Given an object reference, \p ref, H5Rget_obj_type2() returns the
* type of the referenced object in \p obj_type.
*
* A \Emph{reference type} is the type of reference, either an object
* reference or a dataset region reference. An \Emph{object reference}
* points to an HDF5 object while a \Emph{dataset region reference}
* points to a defined region within a dataset.
*
* The \Emph{referenced object} is the object the reference points
* to. The \Emph{referenced object type}, or the type of the referenced
* object, is the type of the object that the reference points to.
*
* The location identifier, \p id, is the identifier for either the
* dataset containing the object reference or the group containing that
* dataset.
*
* Valid reference types, to pass in as \p ref_type, include the
* following:
* \snippet this H5R_type_t_snip
*
* If the application does not already know the object reference type,
* that can be determined with three preliminary calls:
*
* \li Call H5Dget_type() on the dataset containing the reference to
* get a datatype identifier for the dataset’s datatype.
* \li Using that datatype identifier, H5Tget_class() returns a datatype
* class.\n If the datatype class is #H5T_REFERENCE, H5Tequal() can
* then be used to determine whether the reference’s datatype is
* #H5T_STD_REF_OBJ or #H5T_STD_REF_DSETREG:
* - If the datatype is #H5T_STD_REF_OBJ, the reference object type
* is #H5R_OBJECT.
* - If the datatype is #H5T_STD_REF_DSETREG, the reference object
* type is #H5R_DATASET_REGION.
*
* When the function completes successfully, it returns one of the
* following valid object type values (defined in H5Opublic.h):
* \snippet H5Opublic.h H5O_type_t_snip
*
* \since 1.8.0
*
*/
H5_DLL herr_t H5Rget_obj_type2(hid_t id, H5R_type_t ref_type, const void *ref, H5O_type_t *obj_type);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Opens the HDF5 object referenced
*
* \obj_id
* \oapl_id
* \param[in] ref_type The reference type of \p ref
* \param[in] ref Reference to open
*
* \return Returns identifier of referenced object if successful; otherwise
* returns a negative value.
*
* \details Given a reference, \p ref, to an object or a region in an object,
* H5Rdereference2() opens that object and returns an identifier.
*
* The parameter \p obj_id must be a valid identifier for the HDF5 file
* containing the referenced object or for any object in that HDF5
* file.
*
* The parameter \p oapl_id is an object access property list
* identifier for the referenced object. The access property list must
* be of the same type as the object being referenced, that is a group,
* dataset, or datatype property list.
*
* The parameter \p ref_type specifies the reference type of the
* reference \p ref. \p ref_type may contain either of the following
* values:
* - #H5R_OBJECT
* - #H5R_DATASET_REGION
*
* The object opened with this function should be closed when it is no
* longer needed so that resource leaks will not develop. Use the
* appropriate close function such as H5Oclose() or H5Dclose() for
* datasets.
*
* \since 1.10.0
*
*/
H5_DLL hid_t H5Rdereference2(hid_t obj_id, hid_t oapl_id, H5R_type_t ref_type, const void *ref);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Sets up a dataspace and selection as specified by a region reference
*
* \param[in] dataset File identifier or identifier for any object in the file
* containing the referenced region
* \param[in] ref_type Reference type of \p ref, which must be #H5R_DATASET_REGION
* \param[in] ref Region reference to open
*
* \return Returns a valid dataspace identifier if successful; otherwise returns
* a negative value.
*
* \details H5Rget_region() creates a copy of the dataspace of the dataset
* pointed to by a region reference, \p ref, and defines a selection
* matching the selection pointed to by ref within the dataspace copy.
*
* \p dataset is used to identify the file containing the referenced
* region; it can be a file identifier or an identifier for any object
* in the file.
*
* The parameter \p ref_type specifies the reference type of \p ref and
* must contain the value #H5R_DATASET_REGION.
*
* Use H5Sclose() to release the dataspace identifier returned by this
* function when the identifier is no longer needed.
*
*/
H5_DLL hid_t H5Rget_region(hid_t dataset, H5R_type_t ref_type, const void *ref);
/**
* --------------------------------------------------------------------------
* \ingroup H5R
*
* \brief Retrieves a name for a referenced object
*
* \param[in] loc_id Identifier for the file containing the reference or for
* any object in that file
* \param[in] ref_type Type of reference
* \param[in] ref An object or dataset region reference
* \param[out] name A buffer to place the name of the referenced object or
* dataset region. If \c NULL, then this call will return the
* size in bytes of the name.
* \param[in] size The size of the \p name buffer. When the size is passed in,
* the \c NULL terminator needs to be included.
*
* \return Returns the length of the name if successful, returning 0 (zero) if
* no name is associated with the identifier. Otherwise returns a
* negative value.
*
* \details H5Rget_name() retrieves a name for the object identified by \p ref.\n
* \p loc_id is used to identify the file containing the reference. It
* can be the file identifier for the file containing the reference or
* an identifier for any object in that file.
*
* \ref H5R_type_t is the reference type of \p ref. Valid values
* include the following:
* \snippet this H5R_type_t_snip
*
* \p ref is the reference for which the target object’s name is
* sought.
*
* If \p ref is an object reference, \p name will be returned with a
* name for the referenced object. If \p ref is a dataset region
* reference, \p name will contain a name for the object containing the
* referenced region.
*
* Up to \p size characters of the name are returned in \p name;
* additional characters, if any, are not returned to the user
* application.
*
* If the length of the name, which determines the required value of \p
* size, is unknown, a preliminary H5Rget_name() call can be made. The
* return value of this call will be the size of the object name. That
* value can then be assigned to \p size for a second H5Rget_name()
* call, which will retrieve the actual name.
*
* If there is no name associated with the object identifier or if the
* \p name is \c NULL, H5Rget_name() returns the size of the \p name
* buffer (the size does not include the \p NULL terminator).
*
* Note that an object in an HDF5 file may have multiple paths if there
* are multiple links pointing to it. This function may return any one
* of these paths.
*
* \since 1.8.0
*/
H5_DLL ssize_t H5Rget_name(hid_t loc_id, H5R_type_t ref_type, const void *ref, char *name, size_t size);
#ifdef __cplusplus
}
#endif
#endif /* H5Rpublic_H */