H5SMpkg.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 files COPYING and Copyright.html.  COPYING can be found at the root   *
 * of the source code distribution tree; Copyright.html can be found at the  *
 * root level of an installed copy of the electronic HDF5 document set and   *
 * is linked from the top-level documents page.  It can also be found at     *
 * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
 * access to either file, you may request a copy from help@hdfgroup.org.     *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Programmer:  James Laird <jlaird@ncsa.uiuc.edu>
 *              Thursday, March 30, 2006
 *
 * Purpose:     This file contains declarations which are visible only within
 *              the H5SM shared object header messages package.  Source files
 *              outside the H5SM package should include H5SMprivate.h instead.
 */
#ifndef H5SM_PACKAGE
#error "Do not include this file outside the H5SM package!"
#endif

#ifndef _H5SMpkg_H
#define _H5SMpkg_H

/* Get package's private header */
#include "H5SMprivate.h"        /* Shared Object Header Messages        */

/* Other private headers needed by this file */
#include "H5B2private.h"        /* B-trees                              */
#include "H5HFprivate.h"        /* Fractal heaps                        */


/****************************/
/* Package Macros           */
/****************************/

/* Size of checksum information (on disk) */
#define H5SM_SIZEOF_CHECKSUM 4

#define H5SM_HEAP_LOC_SIZE (                                                  \
        4                               /* Reference count */                 \
        + sizeof(H5O_fheap_id_t)        /* size of heap ID on disk */         \
    )

#define H5SM_OH_LOC_SIZE(f) (                                                 \
        1                       /* reserved (possible flags?) */              \
        + 1                     /* message type ID */                         \
        + 2                     /* creation index of message in OH */         \
        + H5F_SIZEOF_ADDR(f)    /* address of OH */                           \
    )

#define H5SM_SOHM_ENTRY_SIZE(f) (                                             \
        1                       /* Message location */                        \
        + 4                     /* Hash value */                              \
        + MAX(H5SM_HEAP_LOC_SIZE, H5SM_OH_LOC_SIZE(f))  /* Entry */           \
    )

#define H5SM_TABLE_SIZE(f) (                                                  \
        H5_SIZEOF_MAGIC                 /* Signature */                       \
         + H5SM_SIZEOF_CHECKSUM         /* Checksum */                        \
    )

#define H5SM_INDEX_HEADER_SIZE(f) (                                           \
        1                       /* Whether index is a list or B-tree */       \
        + 1                     /* Version of index format */                 \
        + 2                     /* Type of messages stored in the index */    \
        + 4                     /* Minimum size of messages to share */       \
        + (3 * 2)               /* B-tree cutoff, list cutoff, # of shared messages */ \
        + H5F_SIZEOF_ADDR(f)    /* Location of list or B-tree */              \
        + H5F_SIZEOF_ADDR(f)    /* Address of heap */                         \
    )

#define H5SM_LIST_SIZE(f, num_mesg) (                                         \
         H5_SIZEOF_MAGIC                /* Signature */                       \
         + (H5SM_SOHM_ENTRY_SIZE(f) * num_mesg) /* Message entries */         \
         + H5SM_SIZEOF_CHECKSUM         /* Checksum */                        \
    )

#define H5SM_B2_NODE_SIZE 512
#define H5SM_B2_SPLIT_PERCENT 100
#define H5SM_B2_MERGE_PERCENT 40

#define H5SM_LIST_VERSION       0       /* Verion of Shared Object Header Message List Indexes */

/****************************/
/* Package Typedefs         */
/****************************/

/* There are a number of Shared Object Header Message-specific structs here.
 *
 * The H5SM_master_table_t is pointed to by the file superblock.  Since a file
 * can have more than one SOHM index, this table collects all the indexes into
 * one place.  It holds an array of H5SM_index_header_t structs.
 *
 * An H5SM_index_header_t is actually the for a given index.  It holds
 * the number of messages in the index, the types of messages in the index,
 * etc.  It also records whether the index is a list or a b-tree, and has
 * the address of the list or b-tree.
 *
 * If the index is a list, the address in the index header should be given
 * to the cache, which can load it into a H5SM_list_t struct.  This is mostly
 * just a header for the cache information; it contains a pointer back to
 * the index header and an unsorted array of messages.
 *
 * These messages are H5SM_sohm_t structs.  They hold the actual SOHM's
 * address, hash value, and refcount.
 *
 * If the index is a b-tree, the H5SM_index_header_t struct holds the address
 * of the b-tree instead of the address of a H5SM_list_t.  The B-tree's nodes
 * are still 'H5SM_sohm_t's.
 *
 * H5SM_mesg_key_t structs are used to search lists and B-trees for a certain
 * message.  They correspond to a message that hasn't yet been written to
 * disk.
 */

/* Where a message is stored */
typedef enum {
    H5SM_NO_LOC = -1,
    H5SM_IN_HEAP = 0,           /* Message is stored in the heap */
    H5SM_IN_OH                  /* Message is stored in an object header */
} H5SM_storage_loc_t;

/* Typedef for a record's location if it's stored in the heap */
typedef struct {
    hsize_t ref_count;          /* Number of times this message is used in the file */
    H5O_fheap_id_t fheap_id;    /* ID of the OHM in the fractal heap */
} H5SM_heap_loc_t;

/* Typedef for a SOHM index node */
typedef struct {
    H5SM_storage_loc_t location;        /* Type of message location */
    uint32_t hash;                      /* Hash value for encoded OHM */
    unsigned msg_type_id;               /* Message's type ID */
    union {
        H5O_mesg_loc_t mesg_loc;        /* Location of message in object header */
        H5SM_heap_loc_t heap_loc;       /* Heap ID for message in SOHM heap */
    } u;
} H5SM_sohm_t;

/* Types of message indices */
typedef enum {
    H5SM_BADTYPE = -1,
    H5SM_LIST,                  /* Index is an unsorted list */
    H5SM_BTREE                  /* Index is a sorted B-tree */
} H5SM_index_type_t;

/* Typedef for a SOHM index header */
typedef struct {
    unsigned mesg_types;        /* Bit flag vector of message types */
    size_t min_mesg_size;       /* number of messages being tracked */
    size_t list_max;            /* >= this many messages, index with a B-tree */
    size_t btree_min;           /* <= this many messages, index with a list again */
    size_t num_messages;        /* number of messages being tracked */
    H5SM_index_type_t index_type; /* Is the index a list or a B-tree? */
    haddr_t index_addr;         /* Address of the actual index (list or B-tree) */
    haddr_t heap_addr;          /* Address of the fheap used to store shared messages */
} H5SM_index_header_t;

/* Typedef for a SOHM list */
typedef struct {
    /* Information for H5AC cache functions, _must_ be first field in structure */
    H5AC_info_t cache_info;

    H5SM_index_header_t *header;    /* Pointer to the corresponding index header */
    H5SM_sohm_t *messages;          /* Actual list, stored as an array */
} H5SM_list_t;


/* Typedef for shared object header message master table */
struct H5SM_master_table_t {
    /* Information for H5AC cache functions, _must_ be first field in structure */
    H5AC_info_t cache_info;

    unsigned num_indexes;           /* Number of indexes */
    H5SM_index_header_t *indexes;   /* Array of num_indexes indexes */
};

/* Typedef for searching an index (list or B-tree) */
typedef struct {
    H5F_t *file;                        /* File in which sharing is happening */
    hid_t dxpl_id;                      /* DXPL for sharing messages in heap */
    H5HF_t *fheap;                      /* The heap for this message type, open. */
    void *encoding;                     /* The message encoded, or NULL */
    size_t encoding_size;               /* Size of the encoding, or 0 */
    H5SM_sohm_t message;                /* The message to find/insert.
                                         * If the message doesn't yet have a
                                         * heap ID, the heap ID will be 0. */
} H5SM_mesg_key_t;

/*
 * Data exchange structure to pass through the fractal heap layer for the
 * H5HF_op function when computing a hash value for a message.
 */
typedef struct {
    /* downward (internal) */
    unsigned    type_id;                /* Message type */

    /* upward */
    uint32_t    hash;                   /* Hash value */
} H5SM_fh_ud_gh_t;

/* Typedef to increment a reference count in the B-tree */
typedef struct {
    H5SM_mesg_key_t *key;       /* IN: key for message being incremented */
    H5O_fheap_id_t fheap_id;    /* OUT: fheap ID of record */
    hid_t dxpl_id;
} H5SM_incr_ref_opdata;


/****************************/
/* Package Variables        */
/****************************/

/* Declare free lists to manage H5SM structs */
H5FL_EXTERN(H5SM_master_table_t);
H5FL_ARR_EXTERN(H5SM_index_header_t);
H5FL_EXTERN(H5SM_list_t);
H5FL_ARR_EXTERN(H5SM_sohm_t);

H5_DLLVAR const H5AC_class_t H5AC_SOHM_TABLE[1];
H5_DLLVAR const H5AC_class_t H5AC_SOHM_LIST[1];
H5_DLLVAR const H5B2_class_t H5SM_INDEX[1];

/****************************/
/* Package Prototypes       */
/****************************/

/* General routines */
H5_DLL ssize_t H5SM_get_index(const H5SM_master_table_t *table, unsigned type_id);

/* Encode and decode routines, used for B-tree and cache encoding/decoding */
H5_DLL herr_t H5SM_message_encode(const H5F_t *f, uint8_t *raw,
    const void *native);
H5_DLL herr_t H5SM_message_decode(const H5F_t *f, const uint8_t *raw,
    void *native);

/* Callbacks to give to B-tree traversals */
/* H5SM_message_compare is in H5SMbtree2.c, but is also used by list code
 * in H5SM.c.
 */
H5_DLL herr_t H5SM_message_compare(const void *rec1,
                                   const void *rec2);

/* H5B2_remove_t callback to add messages to a list index */
H5_DLL herr_t H5SM_btree_convert_to_list_op(const void * record, void *op_data);

/* Fractal heap 'op' callback to compute hash value for message "in place" */
H5_DLL herr_t H5SM_get_hash_fh_cb(const void *obj, size_t obj_len, void *_udata);

/* Testing functions */
#ifdef H5SM_TESTING
H5_DLL herr_t H5SM_get_mesg_count_test(H5F_t *f, hid_t dxpl_id, unsigned type_id,
    size_t *mesg_count);
#endif /* H5SM_TESTING */

#endif /* _H5SMpkg_H */