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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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.     *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*-------------------------------------------------------------------------
 *
 * Created:		H5Pdapl.c
 *			October 27, 2008
 *			Neil Fortner <nfortne2@hdfgroup.org>
 *
 * Purpose:		Dataset access property list class routines
 *
 *-------------------------------------------------------------------------
 */

/****************/
/* Module Setup */
/****************/

#include "H5Pmodule.h"          /* This source code file is part of the H5P module */


/***********/
/* Headers */
/***********/
#include "H5private.h"		/* Generic Functions */
#include "H5Dprivate.h"		/* Datasets */
#include "H5Eprivate.h"		/* Error handling */
#include "H5Fprivate.h"		/* Files */
#include "H5Iprivate.h"		/* IDs */
#include "H5Ppkg.h"		/* Property lists */


/****************/
/* Local Macros */
/****************/

/* ========= Dataset Access properties ============ */
/* Definitions for size of raw data chunk cache(slots) */
#define H5D_ACS_DATA_CACHE_NUM_SLOTS_SIZE       sizeof(size_t)
#define H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF        H5D_CHUNK_CACHE_NSLOTS_DEFAULT
#define H5D_ACS_DATA_CACHE_NUM_SLOTS_ENC        H5P__encode_chunk_cache_nslots
#define H5D_ACS_DATA_CACHE_NUM_SLOTS_DEC        H5P__decode_chunk_cache_nslots
/* Definition for size of raw data chunk cache(bytes) */
#define H5D_ACS_DATA_CACHE_BYTE_SIZE_SIZE       sizeof(size_t)
#define H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF        H5D_CHUNK_CACHE_NBYTES_DEFAULT
#define H5D_ACS_DATA_CACHE_BYTE_SIZE_ENC        H5P__encode_chunk_cache_nbytes
#define H5D_ACS_DATA_CACHE_BYTE_SIZE_DEC        H5P__decode_chunk_cache_nbytes
/* Definition for preemption read chunks first */
#define H5D_ACS_PREEMPT_READ_CHUNKS_SIZE        sizeof(double)
#define H5D_ACS_PREEMPT_READ_CHUNKS_DEF         H5D_CHUNK_CACHE_W0_DEFAULT
#define H5D_ACS_PREEMPT_READ_CHUNKS_ENC         H5P__encode_double
#define H5D_ACS_PREEMPT_READ_CHUNKS_DEC         H5P__decode_double

/******************/
/* Local Typedefs */
/******************/


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


/********************/
/* Local Prototypes */
/********************/

/* Property class callbacks */
static herr_t H5P__dacc_reg_prop(H5P_genclass_t *pclass);
static herr_t H5P__encode_chunk_cache_nslots(const void *value, void **_pp,
    size_t *size);
static herr_t H5P__decode_chunk_cache_nslots(const void **_pp, void *_value);
static herr_t H5P__encode_chunk_cache_nbytes(const void *value, void **_pp,
    size_t *size);
static herr_t H5P__decode_chunk_cache_nbytes(const void **_pp, void *_value);


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

/* Dataset access property list class library initialization object */
const H5P_libclass_t H5P_CLS_DACC[1] = {{
    "dataset access",		/* Class name for debugging     */
    H5P_TYPE_DATASET_ACCESS,    /* Class type                   */

    &H5P_CLS_LINK_ACCESS_g,	/* Parent class                 */
    &H5P_CLS_DATASET_ACCESS_g,	/* Pointer to class             */
    &H5P_CLS_DATASET_ACCESS_ID_g,	/* Pointer to class ID          */
    &H5P_LST_DATASET_ACCESS_ID_g,	/* Pointer to default property list ID */
    H5P__dacc_reg_prop,		/* Default property registration routine */

    NULL,		        /* Class creation callback      */
    NULL,		        /* Class creation callback info */
    NULL,		        /* Class copy callback          */
    NULL,		        /* Class copy callback info     */
    NULL,		        /* Class close callback         */
    NULL 		        /* Class close callback info    */
}};


/*****************************/
/* Library Private Variables */
/*****************************/


/*******************/
/* Local Variables */
/*******************/



/*-------------------------------------------------------------------------
 * Function:    H5P__dacc_reg_prop
 *
 * Purpose:     Register the dataset access property list class's
 *              properties
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Neil Fortner
 *              October 27, 2008
 *-------------------------------------------------------------------------
 */
static herr_t
H5P__dacc_reg_prop(H5P_genclass_t *pclass)
{
    size_t rdcc_nslots = H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF;      /* Default raw data chunk cache # of slots */
    size_t rdcc_nbytes = H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF;      /* Default raw data chunk cache # of bytes */
    double rdcc_w0 = H5D_ACS_PREEMPT_READ_CHUNKS_DEF;           /* Default raw data chunk cache dirty ratio */
    herr_t ret_value = SUCCEED;         /* Return value */

    FUNC_ENTER_STATIC

    /* Register the size of raw data chunk cache (elements) */
    if(H5P_register_real(pclass, H5D_ACS_DATA_CACHE_NUM_SLOTS_NAME, H5D_ACS_DATA_CACHE_NUM_SLOTS_SIZE, &rdcc_nslots, 
             NULL, NULL, NULL, H5D_ACS_DATA_CACHE_NUM_SLOTS_ENC, H5D_ACS_DATA_CACHE_NUM_SLOTS_DEC, NULL, NULL, NULL, NULL) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")

    /* Register the size of raw data chunk cache(bytes) */
    if(H5P_register_real(pclass, H5D_ACS_DATA_CACHE_BYTE_SIZE_NAME, H5D_ACS_DATA_CACHE_BYTE_SIZE_SIZE, &rdcc_nbytes, 
             NULL, NULL, NULL, H5D_ACS_DATA_CACHE_BYTE_SIZE_ENC, H5D_ACS_DATA_CACHE_BYTE_SIZE_DEC, NULL, NULL, NULL, NULL) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")

    /* Register the preemption for reading chunks */
    if(H5P_register_real(pclass, H5D_ACS_PREEMPT_READ_CHUNKS_NAME, H5D_ACS_PREEMPT_READ_CHUNKS_SIZE, &rdcc_w0, 
             NULL, NULL, NULL, H5D_ACS_PREEMPT_READ_CHUNKS_ENC, H5D_ACS_PREEMPT_READ_CHUNKS_DEC, NULL, NULL, NULL, NULL) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5P__dacc_reg_prop() */


/*-------------------------------------------------------------------------
 * Function:	H5Pset_chunk_cache
 *
 * Purpose:	Set the number of objects in the meta data cache and the
 *		maximum number of chunks and bytes in the raw data chunk cache.
 *      Once set, these values will override the values in the file access
 *      property list.  Each of thhese values can be individually unset
 *      (or not set at all) by passing the macros:
 *      H5D_CHUNK_CACHE_NCHUNKS_DEFAULT,
 *      H5D_CHUNK_CACHE_NSLOTS_DEFAULT, and/or
 *      H5D_CHUNK_CACHE_W0_DEFAULT
 *      as appropriate.
 *
 * 		The RDCC_W0 value should be between 0 and 1 inclusive and
 *		indicates how much chunks that have been fully read or fully
 *		written are favored for preemption.  A value of zero means
 *		fully read or written chunks are treated no differently than
 *		other chunks (the preemption is strictly LRU) while a value
 *		of one means fully read chunks are always preempted before
 *		other chunks.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Neil Fortner
 *              Monday, October 27, 2008
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_chunk_cache(hid_t dapl_id, size_t rdcc_nslots, size_t rdcc_nbytes, double rdcc_w0)
{
    H5P_genplist_t *plist;      /* Property list pointer */
    herr_t ret_value = SUCCEED; /* return value */

    FUNC_ENTER_API(FAIL)
    H5TRACE4("e", "izzd", dapl_id, rdcc_nslots, rdcc_nbytes, rdcc_w0);

    /* Check arguments.  Note that we allow negative values - they are
     * considered to "unset" the property. */
    if(rdcc_w0 > (double)1.0f)
        HGOTO_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "raw data cache w0 value must be between 0.0 and 1.0 inclusive, or H5D_CHUNK_CACHE_W0_DEFAULT");

    /* Get the plist structure */
    if(NULL == (plist = H5P_object_verify(dapl_id,H5P_DATASET_ACCESS)))
        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID");

    /* Set sizes */
    if(H5P_set(plist, H5D_ACS_DATA_CACHE_NUM_SLOTS_NAME, &rdcc_nslots) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET,FAIL, "can't set data cache number of chunks");
    if(H5P_set(plist, H5D_ACS_DATA_CACHE_BYTE_SIZE_NAME, &rdcc_nbytes) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET,FAIL, "can't set data cache byte size");
    if(H5P_set(plist, H5D_ACS_PREEMPT_READ_CHUNKS_NAME, &rdcc_w0) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET,FAIL, "can't set preempt read chunks");

done:
    FUNC_LEAVE_API(ret_value)
} /* end H5Pset_chunk_cache() */


/*-------------------------------------------------------------------------
 * Function:	H5Pget_chunk_cache
 *
 * Purpose:	Retrieves the maximum possible number of elements in the meta
 *		data cache and the maximum possible number of elements and
 *		bytes and the RDCC_W0 value in the raw data chunk cache.  Any
 *		(or all) arguments may be null pointers in which case the
 *		corresponding datum is not returned.  If these properties have
 *      not been set on this property list, the default values for a
 *      file access property list are returned.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Neil Fortner
 *              Monday, October 27, 2008
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_chunk_cache(hid_t dapl_id, size_t *rdcc_nslots, size_t *rdcc_nbytes, double *rdcc_w0)
{
    H5P_genplist_t *plist;      /* Property list pointer */
    H5P_genplist_t *def_plist;  /* Default file access property list */
    herr_t ret_value = SUCCEED; /* return value */

    FUNC_ENTER_API(FAIL)
    H5TRACE4("e", "i*z*z*d", dapl_id, rdcc_nslots, rdcc_nbytes, rdcc_w0);

    /* Get the plist structure */
    if (NULL == (plist = H5P_object_verify(dapl_id, H5P_DATASET_ACCESS)))
        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID");

    /* Get default file access plist */
    if (NULL == (def_plist = (H5P_genplist_t *)H5I_object(H5P_FILE_ACCESS_DEFAULT)))
        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for default fapl ID");

    /* Get the properties.  If a property is set to the default value, the value
     * from the default fapl is used. */
    if (rdcc_nslots) {
        if (H5P_get(plist, H5D_ACS_DATA_CACHE_NUM_SLOTS_NAME, rdcc_nslots) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET,FAIL, "can't get data cache number of slots");
        if (*rdcc_nslots == H5D_CHUNK_CACHE_NSLOTS_DEFAULT)
            if (H5P_get(def_plist, H5F_ACS_DATA_CACHE_NUM_SLOTS_NAME, rdcc_nslots) < 0)
                HGOTO_ERROR(H5E_PLIST, H5E_CANTGET,FAIL, "can't get default data cache number of slots");
    } /* end if */
    if (rdcc_nbytes) {
        if (H5P_get(plist, H5D_ACS_DATA_CACHE_BYTE_SIZE_NAME, rdcc_nbytes) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET,FAIL, "can't get data cache byte size");
        if (*rdcc_nbytes == H5D_CHUNK_CACHE_NBYTES_DEFAULT)
            if (H5P_get(def_plist, H5F_ACS_DATA_CACHE_BYTE_SIZE_NAME, rdcc_nbytes) < 0)
                HGOTO_ERROR(H5E_PLIST, H5E_CANTGET,FAIL, "can't get default data cache byte size");
    } /* end if */
    if (rdcc_w0) {
        if (H5P_get(plist, H5D_ACS_PREEMPT_READ_CHUNKS_NAME, rdcc_w0) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET,FAIL, "can't get preempt read chunks");
        if (*rdcc_w0 < 0)
            if (H5P_get(def_plist, H5F_ACS_PREEMPT_READ_CHUNKS_NAME, rdcc_w0) < 0)
                HGOTO_ERROR(H5E_PLIST, H5E_CANTGET,FAIL, "can't get default preempt read chunks");
    } /* end if */

done:
    FUNC_LEAVE_API(ret_value)
} /* end H5Pget_chunk_cache */


/*-------------------------------------------------------------------------
 * Function:       H5P__encode_chunk_cache_nslots
 *
 * Purpose:        Encode the rdcc_nslots parameter to a serialized
 *                 property list.  Similar to H5P__encode_size_t except
 *                 the value of 255 for the enc_size field is reserved to
 *                 indicate H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF, in which
 *                 nothing further is encoded.
 *
 * Return:         Success:     Non-negative
 *                 Failure:     Negative
 *
 * Programmer:     Neil Fortner
 *                 Wednesday, January 23, 2013
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5P__encode_chunk_cache_nslots(const void *value, void **_pp, size_t *size)
{
    uint64_t enc_value;     /* Property value to encode */
    uint8_t **pp = (uint8_t **)_pp;
    unsigned enc_size;      /* Size of encoded property */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDcompile_assert(sizeof(size_t) <= sizeof(uint64_t));
    HDassert(size);

    /* Determine if this is the default value, in which case only encode
     * enc_size (as 255).  Also set size needed for encoding. */
    if(*(const size_t *)value == H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF) {
        enc_size = 0;
        *size += 1;
    } /* end if */
    else {
        enc_value = (uint64_t)*(const size_t *)value;
        enc_size = H5VM_limit_enc_size(enc_value);
        HDassert(enc_size > 0);
        *size += (1 + enc_size);
    } /* end else */

    HDassert(enc_size < 256);

    if(NULL != *pp) {
        /* Encode the size */
        *(*pp)++ = (uint8_t)enc_size;

        /* Encode the value if necessary */
        if(enc_size != 0) {
            UINT64ENCODE_VAR(*pp, enc_value, enc_size);
        } /* end if */
    } /* end if */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5P__encode_chunk_cache_nslots() */


/*-------------------------------------------------------------------------
 * Function:       H5P__decode_chunk_cache_nslots
 *
 * Purpose:        Decode the rdcc_nslots parameter from a serialized
 *                 property list.  Similar to H5P__decode_size_t except
 *                 the value of 255 for the enc_size field is reserved to
 *                 indicate H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF, in which
 *                 nothing further needs to be decoded.
 *
 * Return:         Success:     Non-negative
 *                 Failure:     Negative
 *
 * Programmer:     Neil Fortner
 *                 Wednesday, January 23, 2013
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5P__decode_chunk_cache_nslots(const void **_pp, void *_value)
{
    size_t *value = (size_t *)_value;   /* Property value to return */
    const uint8_t **pp = (const uint8_t **)_pp;
    uint64_t enc_value;                 /* Decoded property value */
    unsigned enc_size;                  /* Size of encoded property */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity check */
    HDcompile_assert(sizeof(size_t) <= sizeof(uint64_t));
    HDassert(pp);
    HDassert(*pp);
    HDassert(value);

    /* Decode the size */
    enc_size = *(*pp)++;
    HDassert(enc_size < 256);

    /* Determine if enc_size indicates that this is the default value, in which
     * case set value to H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF and return */
    if(enc_size == 0)
        *value = H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF;
    else {
        /* Decode the value */
        UINT64DECODE_VAR(*pp, enc_value, enc_size);
        H5_CHECKED_ASSIGN(*value, uint64_t, enc_value, size_t);
    } /* end else */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5P__decode_chunk_cache_nslots() */


/*-------------------------------------------------------------------------
 * Function:       H5P__encode_chunk_cache_nbytes
 *
 * Purpose:        Encode the rdcc_nbytes parameter to a serialized
 *                 property list.  Similar to H5P__encode_size_t except
 *                 the value of 255 for the enc_size field is reserved to
 *                 indicate H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF, in which
 *                 nothing further is encoded.
 *
 * Return:         Success:     Non-negative
 *                 Failure:     Negative
 *
 * Programmer:     Neil Fortner
 *                 Wednesday, January 23, 2013
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5P__encode_chunk_cache_nbytes(const void *value, void **_pp, size_t *size)
{
    uint64_t enc_value;     /* Property value to encode */
    uint8_t **pp = (uint8_t **)_pp;
    unsigned enc_size;      /* Size of encoded property */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDcompile_assert(sizeof(size_t) <= sizeof(uint64_t));
    HDassert(size);

    /* Determine if this is the default value, in which case only encode
     * enc_size (as 255).  Also set size needed for encoding. */
    if(*(const size_t *)value == H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF) {
        enc_size = 0;
        *size += 1;
    } /* end if */
    else {
        enc_value = (uint64_t)*(const size_t *)value;
        enc_size = H5VM_limit_enc_size(enc_value);
        HDassert(enc_size > 0);
        *size += (1 + enc_size);
    } /* end else */

    HDassert(enc_size < 256);

    if(NULL != *pp) {
        /* Encode the size */
        *(*pp)++ = (uint8_t)enc_size;

        /* Encode the value if necessary */
        if(enc_size != 0) {
            UINT64ENCODE_VAR(*pp, enc_value, enc_size);
        } /* end if */
    } /* end if */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5P__encode_chunk_cache_nbytes() */


/*-------------------------------------------------------------------------
 * Function:       H5P__decode_chunk_cache_nbytes
 *
 * Purpose:        Decode the rdcc_nbytes parameter from a serialized
 *                 property list.  Similar to H5P__decode_size_t except
 *                 the value of 255 for the enc_size field is reserved to
 *                 indicate H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF, in which
 *                 nothing further needs to be decoded.
 *
 * Return:         Success:     Non-negative
 *                 Failure:     Negative
 *
 * Programmer:     Neil Fortner
 *                 Wednesday, January 23, 2013
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5P__decode_chunk_cache_nbytes(const void **_pp, void *_value)
{
    size_t *value = (size_t *)_value;   /* Property value to return */
    const uint8_t **pp = (const uint8_t **)_pp;
    uint64_t enc_value;                 /* Decoded property value */
    unsigned enc_size;                  /* Size of encoded property */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity check */
    HDcompile_assert(sizeof(size_t) <= sizeof(uint64_t));
    HDassert(pp);
    HDassert(*pp);
    HDassert(value);

    /* Decode the size */
    enc_size = *(*pp)++;
    HDassert(enc_size < 256);

    /* Determine if enc_size indicates that this is the default value, in which
     * case set value to H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF and return */
    if(enc_size == 0)
        *value = H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF;
    else {
        /* Decode the value */
        UINT64DECODE_VAR(*pp, enc_value, enc_size);
        H5_CHECKED_ASSIGN(*value, uint64_t, enc_value, size_t);
    } /* end else */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5P__decode_chunk_cache_nbytes() */