path: root/src/H5Oprivate.h

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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://support.hdfgroup.org/ftp/HDF5/releases.  *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*-------------------------------------------------------------------------
 *
 * Created:		H5Oprivate.h
 *			Aug  5 1997
 *			Robb Matzke <matzke@llnl.gov>
 *
 * Purpose:		Object header private include file.
 *
 *-------------------------------------------------------------------------
 */
#ifndef _H5Oprivate_H
#define _H5Oprivate_H

/* Include the public header file for this API */
#include "H5Opublic.h"          /* Object header functions              */

/* Public headers needed by this file */
#include "H5Dpublic.h"          /* Dataset functions                    */
#include "H5Lpublic.h"		/* Link functions                       */
#include "H5Spublic.h"		/* Dataspace functions			*/

/* Private headers needed by this file */
#include "H5ACprivate.h"        /* Metadata cache                       */
#include "H5Fprivate.h"		/* File access				*/
#include "H5SLprivate.h"	/* Skip lists				*/
#include "H5Tprivate.h"		/* Datatype functions			*/
#include "H5Zprivate.h"         /* I/O pipeline filters			*/

/* Forward references of package typedefs */
typedef struct H5O_msg_class_t H5O_msg_class_t;
typedef struct H5O_mesg_t H5O_mesg_t;
typedef struct H5O_t H5O_t;

/* Values used to create the shared message & attribute heaps */
/* (Note that these parameters have been tuned so that the resulting heap ID
 *      is exactly 8 bytes.  This is an efficient size as it can be stored
 *      directly in an 8 byte integer in memory, think carefully before changing it.
 *      -QAK)
 */
#define H5O_FHEAP_MAN_WIDTH                     4
#define H5O_FHEAP_MAN_START_BLOCK_SIZE          1024
#define H5O_FHEAP_MAN_MAX_DIRECT_SIZE           (64 * 1024)
#define H5O_FHEAP_MAN_MAX_INDEX                 40
#define H5O_FHEAP_MAN_START_ROOT_ROWS           1
#define H5O_FHEAP_CHECKSUM_DBLOCKS              TRUE
#define H5O_FHEAP_MAX_MAN_SIZE                  (4 * 1024)
#define H5O_FHEAP_ID_LEN                        8

/* Object header macros */
#define H5O_MESG_MAX_SIZE	65536	/*max obj header message size	     */
#define H5O_ALL		(-1)		/* Operate on all messages of type   */
#define H5O_FIRST	(-2)		/* Operate on first message of type  */

/* Flags needed when encoding messages */
#define H5O_MSG_FLAG_CONSTANT	0x01u
#define H5O_MSG_FLAG_SHARED	0x02u
#define H5O_MSG_FLAG_DONTSHARE	0x04u
#define H5O_MSG_FLAG_FAIL_IF_UNKNOWN_AND_OPEN_FOR_WRITE 0x08u
#define H5O_MSG_FLAG_MARK_IF_UNKNOWN 0x10u
#define H5O_MSG_FLAG_WAS_UNKNOWN 0x20u
#define H5O_MSG_FLAG_SHAREABLE  0x40u
#define H5O_MSG_FLAG_BITS	(H5O_MSG_FLAG_CONSTANT|H5O_MSG_FLAG_SHARED|H5O_MSG_FLAG_DONTSHARE|H5O_MSG_FLAG_FAIL_IF_UNKNOWN_AND_OPEN_FOR_WRITE|H5O_MSG_FLAG_MARK_IF_UNKNOWN|H5O_MSG_FLAG_WAS_UNKNOWN|H5O_MSG_FLAG_SHAREABLE)

/* Flags for updating messages */
#define H5O_UPDATE_TIME         0x01u
#define H5O_UPDATE_FORCE        0x02u   /* Force updating the message */

/* Hash value constants */
#define H5O_HASH_SIZE 32

/* Enable reading/writing "bogus" messages */
/* #define H5O_ENABLE_BOGUS */

/* ========= Object Creation properties ============ */
#define H5O_CRT_ATTR_MAX_COMPACT_NAME	"max compact attr"      /* Max. # of attributes to store compactly */
#define H5O_CRT_ATTR_MIN_DENSE_NAME	"min dense attr"	/* Min. # of attributes to store densely */
#define H5O_CRT_OHDR_FLAGS_NAME		"object header flags"	/* Object header flags */
#define H5O_CRT_PIPELINE_NAME           "pline"                 /* Filter pipeline */
#define H5O_CRT_PIPELINE_DEF            {{0, NULL, H5O_NULL_ID, {{0, HADDR_UNDEF}}}, H5O_PLINE_VERSION_1, 0, 0, NULL}
#ifdef H5O_ENABLE_BOGUS
#define H5O_BOGUS_MSG_FLAGS_NAME        "bogus msg flags"       /* Flags for 'bogus' message */
#define H5O_BOGUS_MSG_FLAGS_SIZE        sizeof(uint8_t)

/* bogus ID can be either (a) H5O_BOGUS_VALID_ID or (b) H5O_BOGUS_INVALID_ID */
#define H5O_BOGUS_MSG_ID_NAME        "bogus msg id"         /* ID for 'bogus' message */
#define H5O_BOGUS_MSG_ID_SIZE        sizeof(unsigned)

#endif /* H5O_ENABLE_BOGUS */
#ifdef H5O_ENABLE_BAD_MESG_COUNT
#define H5O_BAD_MESG_COUNT_NAME         "bad message count"       /* Flag setting bad message count */
#define H5O_BAD_MESG_COUNT_SIZE         sizeof(hbool_t)
#endif /* H5O_ENABLE_BAD_MESG_COUNT */

/* ========= Object Copy properties ============ */
#define H5O_CPY_OPTION_NAME 		 "copy object"           /* Copy options */
#define H5O_CPY_MERGE_COMM_DT_LIST_NAME "merge committed dtype list"   /* List of datatype paths to search in the dest file for merging */
#define H5O_CPY_MCDT_SEARCH_CB_NAME 	 "committed dtype list search" /* Callback function when the search for a matching committed datatype is complete */

/* If the module using this macro is allowed access to the private variables, access them directly */
#ifdef H5O_PACKAGE
#define H5O_OH_GET_ADDR(O)    ((O)->chunk[0].addr)
#else /* H5O_PACKAGE */
#define H5O_OH_GET_ADDR(O)    (H5O_get_oh_addr(O))
#endif /* H5O_PACKAGE */

/* Set the fields in a shared message structure */
#define H5O_UPDATE_SHARED(SH_MESG, SH_TYPE, F, MSG_TYPE, CRT_IDX, OH_ADDR)    \
    {                                                                         \
        (SH_MESG)->type = (SH_TYPE);                                          \
        (SH_MESG)->file = (F);                                                \
        (SH_MESG)->msg_type_id = (MSG_TYPE);                                  \
        (SH_MESG)->u.loc.index = (CRT_IDX);                                   \
        (SH_MESG)->u.loc.oh_addr = (OH_ADDR);                                 \
    } /* end block */


/* Fractal heap ID type for shared message & attribute heap IDs. */
typedef union {
    uint8_t id[H5O_FHEAP_ID_LEN];       /* Buffer to hold ID, for encoding/decoding */
    uint64_t val;                       /* Value, for quick comparisons */
} H5O_fheap_id_t;

/* The object location information for an object */
typedef struct H5O_loc_t {
    H5F_t       *file;          /* File that object header is located within */
    haddr_t     addr;           /* File address of object header */
    hbool_t     holding_file;   /* True if this object header has incremented
                                 * its file's count of open objects. */
} H5O_loc_t;

/* Typedef for linked list of datatype merge suggestions */
typedef struct H5O_copy_dtype_merge_list_t {
    char *path; /* Path to datatype in destination file */
    struct H5O_copy_dtype_merge_list_t *next; /* Next object in list */
} H5O_copy_dtype_merge_list_t;

/* Structure for callback property before searching the global list of committed datatypes at destination */
typedef struct H5O_mcdt_cb_info_t {
    H5O_mcdt_search_cb_t 	func;
    void  			*user_data;
} H5O_mcdt_cb_info_t;

/* Settings/flags for copying an object */
typedef struct H5O_copy_t {
    hbool_t copy_shallow;               /* Flag to perform shallow hierarchy copy */
    hbool_t expand_soft_link;           /* Flag to expand soft links */
    hbool_t expand_ext_link;            /* Flag to expand external links */
    hbool_t expand_ref;                 /* Flag to expand object references */
    hbool_t copy_without_attr;          /* Flag to not copy attributes */
    hbool_t preserve_null;              /* Flag to not delete NULL messages */
    hbool_t merge_comm_dt;             /* Flag to merge committed datatypes in dest file */
    H5O_copy_dtype_merge_list_t *dst_dt_suggestion_list; /* Suggestions for merging committed datatypes */
    int     curr_depth;                 /* Current depth in hierarchy copied */
    int     max_depth;                  /* Maximum depth in hierarchy to copy */
    H5SL_t  *map_list;                  /* Skip list to hold address mappings */
    H5SL_t  *dst_dt_list;               /* Skip list to hold committed datatypes in dest file */
    hbool_t dst_dt_list_complete;       /* Whether the destination datatype list is complete (i.e. not only populated with "suggestions" from H5Padd_merge_committed_dtype_path) */
    H5O_t   *oh_dst;                    /* The destination object header */
    H5O_mcdt_search_cb_t mcdt_cb;	/* The callback to invoke before searching the global list of committed datatypes at destination */
    void *mcdt_ud;			/* User data passed to callback */
} H5O_copy_t;

/* Header message IDs */
#define H5O_NULL_ID             0x0000  /* Null Message.  */
#define H5O_SDSPACE_ID          0x0001  /* Dataspace Message. */
#define H5O_LINFO_ID            0x0002  /* Link info Message. */
#define H5O_DTYPE_ID            0x0003  /* Datatype Message.  */
#define H5O_FILL_ID             0x0004  /* Fill Value Message. (Old)  */
#define H5O_FILL_NEW_ID         0x0005  /* Fill Value Message. (New)  */
#define H5O_LINK_ID             0x0006  /* Link Message. */
#define H5O_EFL_ID              0x0007  /* External File List Message  */
#define H5O_LAYOUT_ID           0x0008  /* Data Layout Message.  */
#define H5O_BOGUS_VALID_ID      0x0009  /* "Bogus valid" Message.  */
#define H5O_GINFO_ID            0x000a  /* Group info Message.  */
#define H5O_PLINE_ID            0x000b  /* Filter pipeline message.  */
#define H5O_ATTR_ID             0x000c  /* Attribute Message.  */
#define H5O_NAME_ID             0x000d  /* Object name message.  */
#define H5O_MTIME_ID            0x000e  /* Modification time message. (Old)  */
#define H5O_SHMESG_ID           0x000f  /* Shared message "SOHM" table. */
#define H5O_CONT_ID             0x0010  /* Object header continuation message.  */
#define H5O_STAB_ID             0x0011  /* Symbol table message.  */
#define H5O_MTIME_NEW_ID        0x0012  /* Modification time message. (New)  */
#define H5O_BTREEK_ID           0x0013  /* v1 B-tree 'K' values message.  */
#define H5O_DRVINFO_ID          0x0014  /* Driver info message.  */
#define H5O_AINFO_ID            0x0015  /* Attribute info message.  */
#define H5O_REFCOUNT_ID         0x0016  /* Reference count message.  */
#define H5O_UNKNOWN_ID          0x0017  /* Placeholder message ID for unknown message.  */
                                        /* (this should never exist in a file) */

/*
 * Note: Must increment H5O_MSG_TYPES in H5Opkg.h and update H5O_msg_class_g
 *      in H5O.c when creating a new message type.  Also bump the value of
 *      H5O_BOGUS_INVALID_ID, below, to be one greater than the value of
 *      H5O_UNKNOWN_ID.
 *
 * (this should never exist in a file)
 */
#define H5O_BOGUS_INVALID_ID    0x0018  /* "Bogus invalid" Message.  */

/* Shared object message types.
 * Shared objects can be committed, in which case the shared message contains
 * the location of the object header that holds the message, or shared in the
 * heap, in which case the shared message holds their heap ID.
 */
#define H5O_SHARE_TYPE_UNSHARED     0           /* Message is not shared */
#define H5O_SHARE_TYPE_SOHM         1           /* Message is stored in SOHM heap */
#define H5O_SHARE_TYPE_COMMITTED    2           /* Message is stored in another object header */
#define H5O_SHARE_TYPE_HERE         3           /* Message is stored in this object header, but is sharable */

/* Detect messages that aren't stored in message's object header */
#define H5O_IS_STORED_SHARED(T) ((((T) == H5O_SHARE_TYPE_SOHM) || ((T) == H5O_SHARE_TYPE_COMMITTED)) ? TRUE : FALSE)

/* Detect shared messages that are "tracked" in some other location */
#define H5O_IS_TRACKED_SHARED(T) ((T) > 0)


/* Specify the object header address and index needed
 *      to locate a message in another object header.
 */
typedef struct H5O_mesg_loc_t {
    H5O_msg_crt_idx_t index;            /* index within object header   */
    haddr_t oh_addr;                    /* address of object header    */
} H5O_mesg_loc_t;


/*
 * Shared object header message info.
 *
 * (This structure is used in other messages that can be shared and will
 * include a H5O_shared_t struct as the first field in their "native" type)
 */
typedef struct H5O_shared_t {
    unsigned type;                      /* Type describing how message is shared */
    H5F_t *file;                        /* File that message is located within */
    unsigned msg_type_id;               /* Message's type ID */
    union {
        H5O_mesg_loc_t	loc;		/* Object location info		     */
        H5O_fheap_id_t  heap_id;        /* ID within the SOHM heap           */
    } u;
} H5O_shared_t;


/*
 * Link Info Message.
 * (Contains dynamic information about links in a group)
 * (Data structure in memory)
 * (if the fields in this struct are changed, remember to change the default
 *      link info structure in src/H5Gprivate.h - QAK)
 * (if the fields in this struct are changed, also look at the code that
 *      creates intermediate groups in src/H5Gtraverse.c - QAK)
 * (The "max. creation order" field is signed so that we might have an easy
 *      way to add links to the front of the creation ordering (with negative
 *      values) as well as the end of the creation ordering - QAK)
 */
typedef struct H5O_linfo_t {
    /* Creation order info */
    hbool_t     track_corder;           /* Are creation order values tracked on links? */
    hbool_t     index_corder;           /* Are creation order values indexed on links? */
    int64_t     max_corder;             /* Current max. creation order value for group */
    haddr_t     corder_bt2_addr;        /* Address of v2 B-tree for indexing creation order values of links */

    /* Storage management info */
    hsize_t     nlinks;                 /* Number of links in the group      */
    haddr_t     fheap_addr;             /* Address of fractal heap for storing "dense" links */
    haddr_t     name_bt2_addr;          /* Address of v2 B-tree for indexing names of links */
} H5O_linfo_t;

/* Initial version of the "old" fill value information */
/* (It doesn't look like this value was ever used in the file -QAK) */
#define H5O_FILL_VERSION_1 	1
/* Revised version of the "new" fill value information */
#define H5O_FILL_VERSION_2 	2
/* Version of the "new" fill value information with smaller default format */
#define H5O_FILL_VERSION_3 	3

/* The latest version of the format.  Look through the 'encode', 'decode'
 *      and 'size' callback for places to change when updating this. */
#define H5O_FILL_VERSION_LATEST H5O_FILL_VERSION_3

/*
 * Fill Value Message.
 * (Data structure in memory for both "old" and "new" fill value messages)
 *
 * The fill value message is fill value plus space allocation time, fill value
 * writing time, whether fill value is defined, and the location of the
 * message if it's shared.
 */

typedef struct H5O_fill_t {
    H5O_shared_t        sh_loc;         /* Shared message info (must be first) */

    unsigned	        version;	/* Encoding version number           */
    H5T_t		*type;		/*type. Null implies same as dataset */
    ssize_t		size;		/*number of bytes in the fill value  */
    void		*buf;		/*the fill value		     */
    H5D_alloc_time_t	alloc_time;	/* time to allocate space	     */
    H5D_fill_time_t	fill_time;	/* time to write fill value	     */
    hbool_t		fill_defined;   /* whether fill value is defined     */
} H5O_fill_t;

/*
 * Link message.
 * (Data structure in memory)
 */
typedef struct H5O_link_hard_t {
    haddr_t	addr;			/* Object header address */
} H5O_link_hard_t;

typedef struct H5O_link_soft_t {
    char	*name;			/* Destination name */
} H5O_link_soft_t;

typedef struct H5O_link_ud_t {
    void	*udata;			/* Opaque data supplied by the user */
    size_t       size;                  /* Size of udata */
} H5O_link_ud_t;

typedef struct H5O_link_t {
    H5L_type_t  type;                   /* Type of link */
    hbool_t     corder_valid;           /* Creation order for link is valid (not stored) */
    int64_t     corder;                 /* Creation order for link (stored if it's valid) */
    H5T_cset_t  cset;                   /* Character set of link name	*/
    char	*name;			/* Link name */
    union {
        H5O_link_hard_t hard;           /* Information for hard links */
        H5O_link_soft_t soft;           /* Information for soft links */
        H5O_link_ud_t ud;               /* Information for user-defined links */
    } u;
} H5O_link_t;

/*
 * External File List Message
 * (Data structure in memory)
 */
#define H5O_EFL_ALLOC		16	/*number of slots to alloc at once   */
#define H5O_EFL_UNLIMITED	H5F_UNLIMITED /*max possible file size	     */

typedef struct H5O_efl_entry_t {
    size_t	name_offset;		/*offset of name within heap	     */
    char	*name;			/*malloc'd name			     */
    off_t	offset;			/*offset of data within file	     */
    hsize_t	size;			/*size allocated within file	     */
} H5O_efl_entry_t;

typedef struct H5O_efl_t {
    haddr_t	heap_addr;		/*address of name heap		     */
    size_t	nalloc;			/*number of slots allocated	     */
    size_t	nused;			/*number of slots used		     */
    H5O_efl_entry_t *slot;		/*array of external file entries     */
} H5O_efl_t;


/*
 * Data Layout Message.
 * (Data structure in file)
 */
#define H5O_LAYOUT_NDIMS	(H5S_MAX_RANK+1)

/* Initial version of the layout information.  Used when space is allocated */
#define H5O_LAYOUT_VERSION_1	1

/* This version added support for delaying allocation */
#define H5O_LAYOUT_VERSION_2	2

/* This version is revised to store just the information needed for each
 *      storage type, and to straighten out problems with contiguous layout's
 *      sizes (was encoding them as 4-byte values when they were really n-byte
 *      values (where n usually is 8)).
 */
#define H5O_LAYOUT_VERSION_3	3


/* Forward declaration of structs used below */
struct H5D_layout_ops_t;                /* Defined in H5Dpkg.h               */
struct H5D_chunk_ops_t;                 /* Defined in H5Dpkg.h               */

typedef struct H5O_storage_contig_t {
    haddr_t	addr;			/* File address of data              */
    hsize_t     size;                   /* Size of data in bytes             */
} H5O_storage_contig_t;

typedef struct H5O_storage_chunk_btree_t {
    haddr_t     dset_ohdr_addr;         /* File address dataset's object header */
    H5RC_t     *shared;			/* Ref-counted shared info for B-tree nodes */
} H5O_storage_chunk_btree_t;

typedef struct H5O_storage_chunk_t {
    H5D_chunk_index_t idx_type;		/* Type of chunk index               */
    haddr_t	idx_addr;		/* File address of chunk index       */
    const struct H5D_chunk_ops_t *ops;  /* Pointer to chunked storage operations */
    union {
        H5O_storage_chunk_btree_t btree; /* Information for v1 B-tree index   */
    } u;
} H5O_storage_chunk_t;

typedef struct H5O_storage_compact_t {
    hbool_t     dirty;                  /* Dirty flag for compact dataset    */
    size_t      size;                   /* Size of buffer in bytes           */
    void        *buf;                   /* Buffer for compact dataset        */
} H5O_storage_compact_t;

typedef struct H5O_storage_t {
    H5D_layout_t type;			/* Type of layout                    */
    union {
        H5O_storage_contig_t contig;    /* Information for contiguous storage */
        H5O_storage_chunk_t chunk;      /* Information for chunked storage    */
        H5O_storage_compact_t compact;  /* Information for compact storage    */
    } u;
} H5O_storage_t;

typedef struct H5O_layout_chunk_t {
    unsigned	ndims;			/* Num dimensions in chunk           */
    uint32_t	dim[H5O_LAYOUT_NDIMS];	/* Size of chunk in elements         */
    uint32_t    size;                   /* Size of chunk in bytes            */
    hsize_t     nchunks;                /* Number of chunks in dataset	     */
    hsize_t     chunks[H5O_LAYOUT_NDIMS]; /* # of chunks in dataset dimensions */
    hsize_t    	down_chunks[H5O_LAYOUT_NDIMS];	/* "down" size of number of chunks in each dimension */
} H5O_layout_chunk_t;

typedef struct H5O_layout_t {
    H5D_layout_t type;			/* Type of layout                    */
    unsigned version;                   /* Version of message                */
    const struct H5D_layout_ops_t *ops; /* Pointer to data layout I/O operations */
    union {
        H5O_layout_chunk_t chunk;       /* Information for chunked layout    */
    } u;
    H5O_storage_t storage;              /* Information for storing dataset elements */
} H5O_layout_t;

#ifdef H5O_ENABLE_BOGUS
/*
 * "Bogus" Message.
 * (Data structure in memory)
 */
#define H5O_BOGUS_VALUE         0xdeadbeef
typedef struct H5O_bogus_t {
    unsigned u;                         /* Hold the bogus info */
} H5O_bogus_t;
#endif /* H5O_ENABLE_BOGUS */

/*
 * Group info message.
 * (Contains constant information about a group)
 * (Data structure in memory)
 * (if the fields in this struct are changed, remember to change the default
 *      group info structure in src/H5Gprivate.h - QAK)
 */
typedef struct H5O_ginfo_t {
    /* "Old" format group info (not stored) */
    uint32_t    lheap_size_hint;        /* Local heap size hint              */

    /* "New" format group info (stored) */

    /* (storage management info) */
    hbool_t     store_link_phase_change;/* Whether to store the link phase change values */
    uint16_t	max_compact;		/* Maximum # of compact links        */
    uint16_t	min_dense;		/* Minimum # of "dense" links        */

    /* (initial object header size info) */
    hbool_t     store_est_entry_info;   /* Whether to store the est. entry values */
    uint16_t	est_num_entries;	/* Estimated # of entries in group   */
    uint16_t	est_name_len;		/* Estimated length of entry name    */
} H5O_ginfo_t;

/*
 * Filter pipeline message.
 * (Data structure in memory)
 */

/* The initial version of the format */
#define H5O_PLINE_VERSION_1	1

/* This version encodes the message fields more efficiently */
/* (Drops the reserved bytes, doesn't align the name and doesn't encode the
 *      filter name at all if it's a filter provided by the library)
 */
#define H5O_PLINE_VERSION_2	2

/* The latest version of the format.  Look through the 'encode' and 'size'
 *      callbacks for places to change when updating this. */
#define H5O_PLINE_VERSION_LATEST H5O_PLINE_VERSION_2

typedef struct H5O_pline_t {
    H5O_shared_t        sh_loc;         /* Shared message info (must be first) */

    unsigned	version;	        /* Encoding version number */
    size_t	nalloc;			/*num elements in `filter' array     */
    size_t	nused;			/*num filters defined		     */
    H5Z_filter_info_t *filter;		/*array of filters		     */
} H5O_pline_t;

/*
 * Object name message.
 * (Data structure in memory)
 */

typedef struct H5O_name_t {
    char	*s;			/*ptr to malloc'd memory	     */
} H5O_name_t;

/*
 * Shared message table message
 * Information about file-wide shared message table, stored in superblock
 * extension
 * (Data structure in memory)
 */
typedef struct H5O_shmesg_table_t {
    haddr_t		addr;	        /*file address of SOHM table */
    unsigned		version;	/*SOHM table version number */
    unsigned		nindexes;	/*number of indexes in the table */
} H5O_shmesg_table_t;

/*
 * Object header continuation message.
 * (Data structure in memory)
 */

typedef struct H5O_cont_t {
    haddr_t	addr;			/*address of continuation block	     */
    size_t	size;			/*size of continuation block	     */

    /* the following field(s) do not appear on disk */
    unsigned	chunkno;		/*chunk this mesg refers to	     */
} H5O_cont_t;

/*
 * Symbol table message.
 * (Data structure in memory)
 */
typedef struct H5O_stab_t {
    haddr_t	btree_addr;		/*address of B-tree		     */
    haddr_t	heap_addr;		/*address of name heap		     */
} H5O_stab_t;

/*
 * v1 B-tree 'K' value message
 * Information about file-wide non-default v1 B-tree 'K' values, stored in
 * superblock extension
 * (Data structure in memory)
 */
typedef struct H5O_btreek_t {
    unsigned        btree_k[H5B_NUM_BTREE_ID];  /* B-tree internal node 'K' values */
    unsigned        sym_leaf_k;                 /* Symbol table leaf node's 'K' value */
} H5O_btreek_t;

/*
 * Driver info message
 * Information about driver info, stored in superblock extension
 * (Data structure in memory)
 */
typedef struct H5O_drvinfo_t {
    char                name[9];                /* Driver name */
    size_t		len;                    /* Length of encoded buffer */
    uint8_t            *buf;                    /* Buffer for encoded info */
} H5O_drvinfo_t;

/*
 * Attribute Info Message.
 * (Contains dynamic information about attributes on an object)
 * (Data structure in memory)
 */
typedef struct H5O_ainfo_t {
    /* Creation order info */
    hbool_t     track_corder;           /* Are creation order values tracked on attributes? */
    hbool_t     index_corder;           /* Are creation order values indexed on attributes? */
    H5O_msg_crt_idx_t max_crt_idx;      /* Maximum attribute creation index used */
    haddr_t     corder_bt2_addr;        /* Address of v2 B-tree for indexing creation order values of "dense" attributes */

    /* Storage management info */
    hsize_t     nattrs;                 /* Number of attributes on the object */
    haddr_t     fheap_addr;             /* Address of fractal heap for storing "dense" attributes */
    haddr_t     name_bt2_addr;          /* Address of v2 B-tree for indexing names of "dense" attributes */
} H5O_ainfo_t;

/*
 * Reference Count Message.
 * (Data structure in memory)
 */
typedef uint32_t H5O_refcount_t;        /* Contains # of links to object, if >1 */

/*
 * "Unknown" Message.
 * (Data structure in memory)
 */
typedef unsigned H5O_unknown_t;         /* Original message type ID */


/* Typedef for "application" iteration operations */
typedef herr_t (*H5O_operator_t)(const void *mesg/*in*/, unsigned idx,
    void *operator_data/*in,out*/);

/* Typedef for "internal library" iteration operations */
typedef herr_t (*H5O_lib_operator_t)(H5O_t *oh, H5O_mesg_t *mesg/*in,out*/,
    unsigned sequence, unsigned *oh_modified/*out*/, void *operator_data/*in,out*/);

/* Some syntactic sugar to make the compiler happy with two different kinds of iterator callbacks */
typedef enum H5O_mesg_operator_type_t {
    H5O_MESG_OP_APP,            /* Application callback */
    H5O_MESG_OP_LIB             /* Library internal callback */
} H5O_mesg_operator_type_t;

/* To indicate that the object header is just modified */
#define H5O_MODIFY		0x01
/* To indicate that the object header is modified and might possibly need to condense messages */
#define H5O_MODIFY_CONDENSE	0x02

typedef struct {
    H5O_mesg_operator_type_t op_type;
    union {
        H5O_operator_t app_op;      /* Application callback for each message */
        H5O_lib_operator_t lib_op;  /* Library internal callback for each message */
    } u;
} H5O_mesg_operator_t;


/* Typedef for abstract object creation */
typedef struct {
    H5O_type_t obj_type;        /* Type of object to create */
    void *crt_info;             /* Information for object creation callback */
    void *new_obj;              /* Pointer to new object created */
} H5O_obj_create_t;

/* Forward declarations for prototype arguments */
struct H5P_genplist_t;

/* Object header routines */
H5_DLL herr_t H5O_init(void);
H5_DLL herr_t H5O_create(H5F_t *f, hid_t dxpl_id, size_t size_hint,
    size_t initial_rc, hid_t ocpl_id, H5O_loc_t *loc/*out*/);
H5_DLL herr_t H5O_open(H5O_loc_t *loc);
H5_DLL herr_t H5O_close(H5O_loc_t *loc);
H5_DLL int H5O_link(const H5O_loc_t *loc, int adjust, hid_t dxpl_id);
H5_DLL H5O_t *H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, H5AC_protect_t prot);
H5_DLL H5O_t *H5O_pin(const H5O_loc_t *loc, hid_t dxpl_id);
H5_DLL herr_t H5O_unpin(H5O_t *oh);
H5_DLL herr_t H5O_dec_rc_by_loc(const H5O_loc_t *loc, hid_t dxpl_id);
H5_DLL herr_t H5O_unprotect(const H5O_loc_t *loc, hid_t dxpl_id, H5O_t *oh,
    unsigned oh_flags);
H5_DLL herr_t H5O_touch(const H5O_loc_t *loc, hbool_t force, hid_t dxpl_id);
H5_DLL herr_t H5O_touch_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh,
    hbool_t force);
#ifdef H5O_ENABLE_BOGUS
H5_DLL herr_t H5O_bogus_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned mesg_id, unsigned mesg_flags);
#endif /* H5O_ENABLE_BOGUS */
H5_DLL herr_t H5O_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr);
H5_DLL herr_t H5O_get_hdr_info(const H5O_loc_t *oloc, hid_t dxpl_id, H5O_hdr_info_t *hdr);
H5_DLL herr_t H5O_get_info(const H5O_loc_t *oloc, hid_t dxpl_id, hbool_t want_ih_info,
    H5O_info_t *oinfo);
H5_DLL herr_t H5O_obj_type(const H5O_loc_t *loc, H5O_type_t *obj_type, hid_t dxpl_id);
H5_DLL herr_t H5O_get_create_plist(const H5O_loc_t *loc, hid_t dxpl_id, struct H5P_genplist_t *oc_plist);
H5_DLL hid_t H5O_open_name(H5G_loc_t *loc, const char *name, hid_t lapl_id, hbool_t app_ref);
H5_DLL herr_t H5O_get_nlinks(const H5O_loc_t *loc, hid_t dxpl_id, hsize_t *nlinks);
H5_DLL void *H5O_obj_create(H5F_t *f, H5O_type_t obj_type, void *crt_info, H5G_loc_t *obj_loc, hid_t dxpl_id);
H5_DLL haddr_t H5O_get_oh_addr(const H5O_t *oh);
H5_DLL herr_t H5O_get_rc_and_type(const H5O_loc_t *oloc, hid_t dxpl_id, unsigned *rc, H5O_type_t *otype);

/* Object header message routines */
H5_DLL herr_t H5O_msg_create(const H5O_loc_t *loc, unsigned type_id, unsigned mesg_flags,
    unsigned update_flags, void *mesg, hid_t dxpl_id);
H5_DLL herr_t H5O_msg_append_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned type_id,
    unsigned mesg_flags, unsigned update_flags, void *mesg);
H5_DLL herr_t H5O_msg_write(const H5O_loc_t *loc, unsigned type_id,
    unsigned mesg_flags, unsigned update_flags, void *mesg, hid_t dxpl_id);
H5_DLL herr_t H5O_msg_write_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh,
    unsigned type_id, unsigned mesg_flags, unsigned update_flags, void *mesg);
H5_DLL void *H5O_msg_read(const H5O_loc_t *loc, unsigned type_id, void *mesg,
    hid_t dxpl_id);
H5_DLL void *H5O_msg_read_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned type_id,
    void *mesg);
H5_DLL herr_t H5O_msg_reset(unsigned type_id, void *native);
H5_DLL void *H5O_msg_free(unsigned type_id, void *mesg);
H5_DLL void *H5O_msg_copy(unsigned type_id, const void *mesg, void *dst);
H5_DLL int H5O_msg_count(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id);
H5_DLL htri_t H5O_msg_exists(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id);
H5_DLL htri_t H5O_msg_exists_oh(const H5O_t *oh, unsigned type_id);
H5_DLL herr_t H5O_msg_remove(const H5O_loc_t *loc, unsigned type_id, int sequence,
    hbool_t adj_link, hid_t dxpl_id);
H5_DLL herr_t H5O_msg_remove_op(const H5O_loc_t *loc, unsigned type_id, int sequence,
    H5O_operator_t op, void *op_data, hbool_t adj_link, hid_t dxpl_id);
H5_DLL herr_t H5O_msg_iterate(const H5O_loc_t *loc, unsigned type_id,
    const H5O_mesg_operator_t *op, void *op_data, hid_t dxpl_id);
H5_DLL size_t H5O_msg_raw_size(const H5F_t *f, unsigned type_id,
    hbool_t disable_shared, const void *mesg);
H5_DLL size_t H5O_msg_size_f(const H5F_t *f, hid_t ocpl_id, unsigned type_id,
    const void *mesg, size_t extra_raw);
H5_DLL size_t H5O_msg_size_oh(const H5F_t *f, const H5O_t *oh, unsigned type_id,
    const void *mesg, size_t extra_raw);
H5_DLL htri_t H5O_msg_is_shared(unsigned type_id, const void *mesg);
H5_DLL htri_t H5O_msg_can_share(unsigned type_id, const void *mesg);
H5_DLL htri_t H5O_msg_can_share_in_ohdr(unsigned type_id);
H5_DLL herr_t H5O_msg_set_share(unsigned type_id, const H5O_shared_t *share,
    void *mesg);
H5_DLL herr_t H5O_msg_reset_share(unsigned type_id, void *mesg);
H5_DLL herr_t H5O_msg_get_crt_index(unsigned type_id, const void *mesg,
    H5O_msg_crt_idx_t *crt_idx);
H5_DLL herr_t H5O_msg_encode(H5F_t *f, unsigned type_id, hbool_t disable_shared,
    unsigned char *buf, const void *obj);
H5_DLL void* H5O_msg_decode(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh,
    unsigned type_id, const unsigned char *buf);
H5_DLL herr_t H5O_msg_delete(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh,
    unsigned type_id, void *mesg);
H5_DLL int H5O_msg_get_chunkno(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id);
H5_DLL herr_t H5O_msg_lock(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id);
H5_DLL herr_t H5O_msg_unlock(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id);

/* Object copying routines */
H5_DLL herr_t H5O_copy_header_map(const H5O_loc_t *oloc_src, H5O_loc_t *oloc_dst /*out */,
    hid_t dxpl_id, H5O_copy_t *cpy_info, hbool_t inc_depth,
    H5O_type_t *obj_type, void **udata);
H5_DLL herr_t H5O_copy_expand_ref(H5F_t *file_src, void *_src_ref, hid_t dxpl_id,
    H5F_t *file_dst, void *_dst_ref, size_t ref_count, H5R_type_t ref_type,
    H5O_copy_t *cpy_info);

/* Debugging routines */
H5_DLL herr_t H5O_debug_id(unsigned type_id, H5F_t *f, hid_t dxpl_id, const void *mesg, FILE *stream, int indent, int fwidth);
H5_DLL herr_t H5O_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE * stream, int indent,
			 int fwidth);

/* These functions operate on object locations */
H5_DLL herr_t H5O_loc_reset(H5O_loc_t *loc);
H5_DLL herr_t H5O_loc_copy(H5O_loc_t *dst, H5O_loc_t *src, H5_copy_depth_t depth);
H5_DLL herr_t H5O_loc_hold_file(H5O_loc_t *loc);
H5_DLL herr_t H5O_loc_free(H5O_loc_t *loc);

/* EFL operators */
H5_DLL hsize_t H5O_efl_total_size(H5O_efl_t *efl);

/* Fill value operators */
H5_DLL herr_t H5O_fill_reset_dyn(H5O_fill_t *fill);
H5_DLL herr_t H5O_fill_convert(H5O_fill_t *fill, H5T_t *type, hbool_t *fill_changed, hid_t dxpl_id);
H5_DLL herr_t H5O_fill_set_latest_version(H5O_fill_t *fill);

/* Link operators */
H5_DLL herr_t H5O_link_delete(H5F_t *f, hid_t dxpl_id, H5O_t *open_oh,
    void *_mesg);

/* Filter pipeline operators */
H5_DLL herr_t H5O_pline_set_latest_version(H5O_pline_t *pline);

/* Shared message operators */
H5_DLL herr_t H5O_set_shared(H5O_shared_t *dst, const H5O_shared_t *src);

#endif /* _H5Oprivate_H */