/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * 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.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * 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.
 */
#if !(defined H5SM_FRIEND || defined H5SM_MODULE)
#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 "H5ACprivate.h" /* Metadata Cache		  	*/
#include "H5B2private.h" /* B-trees                              */
#include "H5HFprivate.h" /* Fractal heaps		  	*/
#include "H5FLprivate.h" /* Free Lists                           */

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

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

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

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

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

#define H5SM_INDEX_HEADER_SIZE(f)                                                                            \
    ((unsigned)1          /* Whether index is a list or B-tree */                                            \
     + (unsigned)1        /* Version of index format */                                                      \
     + (unsigned)2        /* Type of messages stored in the index */                                         \
     + (unsigned)4        /* Minimum size of messages to share */                                            \
     + (unsigned)(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 */                                                              \
    )

/* Format overhead for all SOHM tree metadata in the file */
#define H5SM_METADATA_PREFIX_SIZE                                                                            \
    (H5_SIZEOF_MAGIC        /* Signature */                                                                  \
     + H5SM_SIZEOF_CHECKSUM /* Checksum */                                                                   \
    )

#define H5SM_TABLE_SIZE(f)                                                                                   \
    (/* General metadata fields */                                                                           \
     H5SM_METADATA_PREFIX_SIZE                                                                               \
                                                                                                             \
     /* Indices */                                                                                           \
     + (H5F_SOHM_NINDEXES(f) * H5SM_INDEX_HEADER_SIZE(f)))

#define H5SM_LIST_SIZE(f, num_mesg)                                                                          \
    (/* General metadata fields */                                                                           \
     H5SM_METADATA_PREFIX_SIZE                                                                               \
                                                                                                             \
     /* Message entries */                                                                                   \
     + (H5SM_SOHM_ENTRY_SIZE(f) * num_mesg))

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

#define H5SM_LIST_VERSION 0 /* Version 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 {
    /* Stored */
    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 */

    /* Not stored */
    size_t list_size; /* Size of list index on disk */
} 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;

    size_t               table_size;  /* Size of table on disk */
    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 */
    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 */
} H5SM_incr_ref_opdata;

/* v2 B-tree client callback context */
typedef struct H5SM_bt2_ctx_t {
    uint8_t sizeof_addr; /* Size of file addresses */
} H5SM_bt2_ctx_t;

/* Callback info for loading a shared message table index into the cache */
typedef struct H5SM_table_cache_ud_t {
    H5F_t *f; /* File that shared message index stored as a table is in */
} H5SM_table_cache_ud_t;

/* Callback info for loading a shared message list index into the cache */
typedef struct H5SM_list_cache_ud_t {
    H5F_t               *f;      /* File that shared message index stored as a table is in */
    H5SM_index_header_t *header; /* Index header for this list */
} H5SM_list_cache_ud_t;

/****************************/
/* 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 H5B2_class_t H5SM_INDEX[1];

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

/* General routines */
H5_DLL herr_t H5SM__get_index(const H5SM_master_table_t *table, unsigned type_id, ssize_t *idx);

/* Encode and decode routines, used for B-tree and cache encoding/decoding */
H5_DLL herr_t H5SM__message_compare(const void *rec1, const void *rec2, int *result);
H5_DLL herr_t H5SM__message_encode(uint8_t *raw, const void *native, void *ctx);
H5_DLL herr_t H5SM__message_decode(const uint8_t *raw, void *native, void *ctx);

/* Routines to release data structures */
H5_DLL herr_t H5SM__table_free(H5SM_master_table_t *table);
H5_DLL herr_t H5SM__list_free(H5SM_list_t *list);

/* Testing functions */
#ifdef H5SM_TESTING
H5_DLL herr_t H5SM__get_mesg_count_test(H5F_t *f, unsigned type_id, size_t *mesg_count);
#endif /* H5SM_TESTING */

#endif /* H5SMpkg_H */
