/*
 * Copyright © 1999-2001 NCSA
 *                       All rights reserved.
 *
 * Programmer:  Robb Matzke <matzke@llnl.gov>
 *              Monday, July 26, 1999
 */
#ifndef _H5FDpublic_H
#define _H5FDpublic_H

#include "H5public.h"

#define H5_HAVE_VFL 1 /*define a convenient app feature test*/
#define H5FD_VFD_DEFAULT 0   /* Default VFL driver value */

/*
 * Types of allocation requests. The values larger than H5FD_MEM_DEFAULT
 * should not change other than adding new types to the end. These numbers
 * might appear in files.
 */
typedef enum H5FD_mem_t {
    H5FD_MEM_NOLIST     = -1,                   /*must be negative*/
    H5FD_MEM_DEFAULT    = 0,                    /*must be zero*/
    H5FD_MEM_SUPER      = 1,
    H5FD_MEM_BTREE      = 2,
    H5FD_MEM_DRAW       = 3,
    H5FD_MEM_GHEAP      = 4,
    H5FD_MEM_LHEAP      = 5,
    H5FD_MEM_OHDR       = 6,

    H5FD_MEM_NTYPES                             /*must be last*/
} H5FD_mem_t;
/*
 * A free-list map which maps all types of allocation requests to a single
 * free list.  This is useful for drivers that don't really care about
 * keeping different requests segregated in the underlying file and which
 * want to make most efficient reuse of freed memory.  The use of the
 * H5FD_MEM_SUPER free list is arbitrary.
 */
#define H5FD_FLMAP_SINGLE {                                                   \
    H5FD_MEM_SUPER,                     /*default*/                           \
    H5FD_MEM_SUPER,                     /*super*/                             \
    H5FD_MEM_SUPER,                     /*btree*/                             \
    H5FD_MEM_SUPER,                     /*draw*/                              \
    H5FD_MEM_SUPER,                     /*gheap*/                             \
    H5FD_MEM_SUPER,                     /*lheap*/                             \
    H5FD_MEM_SUPER                      /*ohdr*/                              \
}

/*
 * A free-list map which segregates requests into `raw' or `meta' data
 * pools.
 */
#define H5FD_FLMAP_DICHOTOMY {                                                \
    H5FD_MEM_SUPER,                     /*default*/                           \
    H5FD_MEM_SUPER,                     /*super*/                             \
    H5FD_MEM_SUPER,                     /*btree*/                             \
    H5FD_MEM_DRAW,                      /*draw*/                              \
    H5FD_MEM_SUPER,                     /*gheap*/                             \
    H5FD_MEM_SUPER,                     /*lheap*/                             \
    H5FD_MEM_SUPER                      /*ohdr*/                              \
}

/*
 * The default free list map which causes each request type to use it's own
 * free-list.
 */
#define H5FD_FLMAP_DEFAULT {                                                  \
    H5FD_MEM_DEFAULT,                   /*default*/                           \
    H5FD_MEM_DEFAULT,                   /*super*/                             \
    H5FD_MEM_DEFAULT,                   /*btree*/                             \
    H5FD_MEM_DEFAULT,                   /*draw*/                              \
    H5FD_MEM_DEFAULT,                   /*gheap*/                             \
    H5FD_MEM_DEFAULT,                   /*lheap*/                             \
    H5FD_MEM_DEFAULT                    /*ohdr*/                              \
}


/* Define VFL driver features that can be enabled on a per-driver basis */
/* These are returned with the 'query' function pointer in H5FD_class_t */
    /*
     * Defining the H5FD_FEAT_AGGREGATE_METADATA for a VFL driver means that
     * the library will attempt to allocate a larger block for metadata and
     * then sub-allocate each metadata request from that larger block.
     */
#define H5FD_FEAT_AGGREGATE_METADATA    0x00000001
    /*
     * Defining the H5FD_FEAT_ACCUMULATE_METADATA for a VFL driver means that
     * the library will attempt to cache metadata as it is written to the file
     * and build up a larger block of metadata to eventually pass to the VFL
     * 'write' routine.
     */
#define H5FD_FEAT_ACCUMULATE_METADATA   0x00000002
    /*
     * Defining the H5FD_FEAT_DATA_SIEVE for a VFL driver means that
     * the library will attempt to cache raw data as it is read from/written to
     * a file in a "data seive" buffer.  See Rajeev Thakur's papers:
     *  http://www.mcs.anl.gov/~thakur/papers/romio-coll.ps.gz
     *  http://www.mcs.anl.gov/~thakur/papers/mpio-high-perf.ps.gz
     */
#define H5FD_FEAT_DATA_SIEVE            0x00000004
        

/* Forward declaration */
typedef struct H5FD_t H5FD_t;

/* Class information for each file driver */
typedef struct H5FD_class_t {
    const char *name;
    haddr_t maxaddr;
    hsize_t (*sb_size)(H5FD_t *file);
    herr_t (*sb_encode)(H5FD_t *file, char *name/*out*/,
                        unsigned char *p/*out*/);
    herr_t (*sb_decode)(H5FD_t *f, const char *name, const unsigned char *p);
    size_t fapl_size;
    void *(*fapl_get)(H5FD_t *file);
    void *(*fapl_copy)(const void *fapl);
    herr_t (*fapl_free)(void *fapl);
    size_t dxpl_size;
    void *(*dxpl_copy)(const void *dxpl);
    herr_t (*dxpl_free)(void *dxpl);
    H5FD_t *(*open)(const char *name, unsigned flags, hid_t fapl,
                    haddr_t maxaddr);
    herr_t (*close)(H5FD_t *file);
    int (*cmp)(const H5FD_t *f1, const H5FD_t *f2);
    herr_t (*query)(const H5FD_t *f1, unsigned long *flags);
    haddr_t (*alloc)(H5FD_t *file, H5FD_mem_t type, hsize_t size);
    herr_t (*free)(H5FD_t *file, H5FD_mem_t type, haddr_t addr, hsize_t size);
    haddr_t (*get_eoa)(H5FD_t *file);
    herr_t (*set_eoa)(H5FD_t *file, haddr_t addr);
    haddr_t (*get_eof)(H5FD_t *file);
    herr_t (*read)(H5FD_t *file, H5FD_mem_t type, hid_t dxpl, haddr_t addr, hsize_t size,
                   void *buffer);
    herr_t (*write)(H5FD_t *file, H5FD_mem_t type, hid_t dxpl, haddr_t addr, hsize_t size,
                    const void *buffer);
    herr_t (*flush)(H5FD_t *file);
    H5FD_mem_t fl_map[H5FD_MEM_NTYPES];
} H5FD_class_t;

/* A free list is a singly-linked list of address/size pairs. */
typedef struct H5FD_free_t {
    haddr_t             addr;
    hsize_t             size;
    struct H5FD_free_t  *next;
} H5FD_free_t;

/*
 * The main datatype for each driver. Public fields common to all drivers are
 * declared here and the driver appends private fields in memory.
 */
struct H5FD_t {
    hid_t               driver_id;      /*driver ID for this file       */
    const H5FD_class_t  *cls;           /*constant class info           */

    unsigned long feature_flags;  /* VFL Driver feature Flags */
    hsize_t     threshold;      /* Threshold for alignment              */
    hsize_t     alignment;      /* Allocation alignment                 */

    /* Metadata aggregation fields */
    hsize_t def_meta_block_size;  /* Metadata allocation block size (if aggregating metadata) */
    hsize_t cur_meta_block_size;  /* Current size of metadata allocation region left */
    haddr_t eoma;       /* End of metadata allocated region */

    /* Metadata accumulator fields */
    unsigned char *meta_accum;  /* Buffer to hold the accumulated metadata */
    haddr_t accum_loc;      /* File location (offset) of the accumulated metadata */
    hsize_t accum_size;     /* Size of the accumulated metadata buffer used (in bytes) */
    hsize_t accum_buf_size; /* Size of the accumulated metadata buffer allocated (in bytes) */
    unsigned accum_dirty;   /* Flag to indicate that the accumulated metadata is dirty */

    haddr_t             maxaddr;        /*for this file, overrides class*/
    H5FD_free_t         *fl[H5FD_MEM_NTYPES];/*freelist per allocation type*/
    hsize_t             maxsize;        /*largest object on FL, or zero */
};

#ifdef __cplusplus
extern "C" {
#endif

/* Function prototypes */
__DLL__ hid_t H5FDregister(const H5FD_class_t *cls);
__DLL__ herr_t H5FDunregister(hid_t driver_id);
__DLL__ H5FD_t *H5FDopen(const char *name, unsigned flags, hid_t fapl_id,
                 haddr_t maxaddr);
__DLL__ herr_t H5FDclose(H5FD_t *file);
__DLL__ int H5FDcmp(const H5FD_t *f1, const H5FD_t *f2);
__DLL__ int H5FDquery(const H5FD_t *f, unsigned long *flags);
__DLL__ haddr_t H5FDalloc(H5FD_t *file, H5FD_mem_t type, hsize_t size);
__DLL__ herr_t H5FDfree(H5FD_t *file, H5FD_mem_t type, haddr_t addr, hsize_t size);
__DLL__ haddr_t H5FDrealloc(H5FD_t *file, H5FD_mem_t type, haddr_t addr,
                    hsize_t old_size, hsize_t new_size);
__DLL__ haddr_t H5FDget_eoa(H5FD_t *file);
__DLL__ herr_t H5FDset_eoa(H5FD_t *file, haddr_t eof);
__DLL__ haddr_t H5FDget_eof(H5FD_t *file);
__DLL__ herr_t H5FDread(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, hsize_t size,
                void *buf/*out*/);
__DLL__ herr_t H5FDwrite(H5FD_t *file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, hsize_t size,
                 const void *buf);
__DLL__ herr_t H5FDflush(H5FD_t *file);

#ifdef __cplusplus
}
#endif
#endif
