/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

 * 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 LICENSE 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.                                                        *

 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*-------------------------------------------------------------------------

 *

 * Created:   H5Gcache.c

 *

 * Purpose:   Implement group metadata cache methods

 *

 *-------------------------------------------------------------------------

 */

/****************/

/* Module Setup */

/****************/

#include "H5Gmodule.h" /* This source code file is part of the H5G module */

/***********/

/* Headers */

/***********/

#include "H5private.h"   /* Generic Functions     */

#include "H5Eprivate.h"  /* Error handling        */

#include "H5FLprivate.h" /* Free Lists                               */

#include "H5Gpkg.h"      /* Groups          */

#include "H5MMprivate.h" /* Memory management     */

/****************/

/* Local Macros */

/****************/

#define H5G_NODE_VERS 1 /* Symbol table node version number   */

/******************/

/* Local Typedefs */

/******************/

/********************/

/* Package Typedefs */

/********************/

/********************/

/* Local Prototypes */

/********************/

/* Metadata cache (H5AC) callbacks */

static herr_t H5G__cache_node_get_initial_load_size(void *udata, size_t *image_len);

static void  *H5G__cache_node_deserialize(const void *image, size_t len, void *udata, bool *dirty);

static herr_t H5G__cache_node_image_len(const void *thing, size_t *image_len);

static herr_t H5G__cache_node_serialize(const H5F_t *f, void *image, size_t len, void *thing);

static herr_t H5G__cache_node_free_icr(void *thing);

/*********************/

/* Package Variables */

/*********************/

/*****************************/

/* Library Private Variables */

/*****************************/

/*******************/

/* Local Variables */

/*******************/

/* Symbol table nodes inherit cache-like properties from H5AC */

const H5AC_class_t H5AC_SNODE[1] = {{

    H5AC_SNODE_ID,                         /* Metadata client ID */

    "Symbol table node",                   /* Metadata client name (for debugging) */

    H5FD_MEM_BTREE,                        /* File space memory type for client */

    H5AC__CLASS_NO_FLAGS_SET,              /* Client class behavior flags */

    H5G__cache_node_get_initial_load_size, /* 'get_initial_load_size' callback */

    NULL,                                  /* 'get_final_load_size' callback */

    NULL,                                  /* 'verify_chksum' callback */

    H5G__cache_node_deserialize,           /* 'deserialize' callback */

    H5G__cache_node_image_len,             /* 'image_len' callback */

    NULL,                                  /* 'pre_serialize' callback */

    H5G__cache_node_serialize,             /* 'serialize' callback */

    NULL,                                  /* 'notify' callback */

    H5G__cache_node_free_icr,              /* 'free_icr' callback */

    NULL,                                  /* 'fsf_size' callback */

}};

/* Declare extern the free list to manage the H5G_node_t struct */

H5FL_EXTERN(H5G_node_t);

/* Declare extern the free list to manage sequences of H5G_entry_t's */

H5FL_SEQ_EXTERN(H5G_entry_t);

/*-------------------------------------------------------------------------

 * Function:    H5G__cache_node_get_initial_load_size()

 *

 * Purpose:     Determine the size of the on-disk image of the node, and

 *              return this value in *image_len.

 *

 * Return:      SUCCEED/FAIL

 *-------------------------------------------------------------------------

 */

static herr_t

H5G__cache_node_get_initial_load_size(void *_udata, size_t *image_len)

{

    H5F_t *f = (H5F_t *)_udata; /* User data for callback */

    FUNC_ENTER_PACKAGE_NOERR

    assert(f);

    assert(image_len);

    /* Set the image length size */

    *image_len = (size_t)(H5G_NODE_SIZE(f));

    FUNC_LEAVE_NOAPI(SUCCEED)

} /* end H5G__cache_node_get_initial_load_size() */

/*-------------------------------------------------------------------------

 * Function:    H5G__cache_node_deserialize

 *

 * Purpose:     Given a buffer containing the on disk image of a symbol table

 *              node, allocate an instance of H5G_node_t, load the contents of the

 *              image into it, and return a pointer to the instance.

 *

 *              Note that deserializing the image requires access to the file

 *              pointer, which is not included in the parameter list for this

 *              callback.  Finesse this issue by passing in the file pointer

 *              twice to the H5AC_protect() call -- once as the file pointer

 *              proper, and again as the user data

 *

 * Return:      Success:        Pointer to in core representation

 *              Failure:        NULL

 *-------------------------------------------------------------------------

 */

static void *

H5G__cache_node_deserialize(const void *_image, size_t len, void *_udata, bool H5_ATTR_UNUSED *dirty)

{

    H5F_t         *f         = (H5F_t *)_udata;         /* User data for callback */

    H5G_node_t    *sym       = NULL;                    /* Symbol table node created */

    const uint8_t *image     = (const uint8_t *)_image; /* Pointer to image to deserialize */

    const uint8_t *image_end = image + len - 1;         /* Pointer to end of image buffer */

    void          *ret_value = NULL;

    FUNC_ENTER_PACKAGE

    assert(image);

    assert(len > 0);

    assert(f);

    assert(dirty);

    /* Allocate symbol table data structures */

    if (NULL == (sym = H5FL_CALLOC(H5G_node_t)))

        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed");

    sym->node_size = (size_t)(H5G_NODE_SIZE(f));

    if (NULL == (sym->entry = H5FL_SEQ_CALLOC(H5G_entry_t, (size_t)(2 * H5F_SYM_LEAF_K(f)))))

        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed");

    /* Magic */

    if (H5_IS_BUFFER_OVERFLOW(image, H5_SIZEOF_MAGIC, image_end))

        HGOTO_ERROR(H5E_SYM, H5E_OVERFLOW, NULL, "ran off end of input buffer while decoding");

    if (memcmp(image, H5G_NODE_MAGIC, (size_t)H5_SIZEOF_MAGIC) != 0)

        HGOTO_ERROR(H5E_SYM, H5E_BADVALUE, NULL, "bad symbol table node signature");

    image += H5_SIZEOF_MAGIC;

    /* Version */

    if (H5_IS_BUFFER_OVERFLOW(image, 1, image_end))

        HGOTO_ERROR(H5E_SYM, H5E_OVERFLOW, NULL, "ran off end of input buffer while decoding");

    if (H5G_NODE_VERS != *image++)

        HGOTO_ERROR(H5E_SYM, H5E_VERSION, NULL, "bad symbol table node version");

    /* Reserved */

    if (H5_IS_BUFFER_OVERFLOW(image, 1, image_end))

        HGOTO_ERROR(H5E_SYM, H5E_OVERFLOW, NULL, "ran off end of input buffer while decoding");

    image++;

    /* Number of symbols */

    if (H5_IS_BUFFER_OVERFLOW(image, 2, image_end))

        HGOTO_ERROR(H5E_SYM, H5E_OVERFLOW, NULL, "ran off end of input buffer while decoding");

    UINT16DECODE(image, sym->nsyms);

    /* Entries */

    if (H5G__ent_decode_vec(f, &image, image_end, sym->entry, sym->nsyms) < 0)

        HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, NULL, "unable to decode symbol table entries");

    /* Set return value */

    ret_value = sym;

done:

    if (!ret_value)

        if (sym && H5G__node_free(sym) < 0)

            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, NULL, "unable to destroy symbol table node");

    FUNC_LEAVE_NOAPI(ret_value)

} /* end H5G__cache_node_deserialize() */

/*-------------------------------------------------------------------------

 * Function:    H5G__cache_node_image_len

 *

 * Purpose:     Compute the size of the data structure on disk and return

 *              it in *image_len

 *

 * Return:      SUCCEED/FAIL

 *-------------------------------------------------------------------------

 */

static herr_t

H5G__cache_node_image_len(const void *_thing, size_t *image_len)

{

    const H5G_node_t *sym = (const H5G_node_t *)_thing; /* Pointer to object */

    FUNC_ENTER_PACKAGE_NOERR

    assert(sym);

    assert(sym->cache_info.type == H5AC_SNODE);

    assert(image_len);

    *image_len = sym->node_size;

    FUNC_LEAVE_NOAPI(SUCCEED)

} /* end H5G__cache_node_image_len() */

/*-------------------------------------------------------------------------

 * Function:    H5G__cache_node_serialize

 *

 * Purpose:     Given a correctly sized buffer and an instance of H5G_node_t,

 *              serialize the contents of the instance of H5G_node_t, and write

 *              this data into the supplied buffer.  This buffer will be written

 *              to disk.

 *

 * Return:      SUCCEED/FAIL

 *-------------------------------------------------------------------------

 */

static herr_t

H5G__cache_node_serialize(const H5F_t *f, void *_image, size_t len, void *_thing)

{

    H5G_node_t *sym       = (H5G_node_t *)_thing; /* Pointer to object */

    uint8_t    *image     = (uint8_t *)_image;    /* Pointer into raw data buffer */

    herr_t      ret_value = SUCCEED;

    FUNC_ENTER_PACKAGE

    assert(f);

    assert(image);

    assert(sym);

    assert(sym->cache_info.type == H5AC_SNODE);

    assert(len == sym->node_size);

    /* Magic number */

    H5MM_memcpy(image, H5G_NODE_MAGIC, (size_t)H5_SIZEOF_MAGIC);

    image += H5_SIZEOF_MAGIC;

    /* Version number */

    *image++ = H5G_NODE_VERS;

    /* Reserved */

    *image++ = 0;

    /* Number of symbols */

    UINT16ENCODE(image, sym->nsyms);

    /* Entries */

    if (H5G__ent_encode_vec(f, &image, sym->entry, sym->nsyms) < 0)

        HGOTO_ERROR(H5E_SYM, H5E_CANTENCODE, FAIL, "can't serialize");

    /* Clear rest of symbol table node */

    memset(image, 0, len - (size_t)(image - (uint8_t *)_image));

done:

    FUNC_LEAVE_NOAPI(ret_value)

} /* end H5G__cache_node_serialize() */

/*-------------------------------------------------------------------------

 * Function:    H5G__cache_node_free_icr

 *

 * Purpose:     Destroy a symbol table node in memory

 *

 * Return:      SUCCEED/FAIL

 *-------------------------------------------------------------------------

 */

static herr_t

H5G__cache_node_free_icr(void *_thing)

{

    H5G_node_t *sym       = (H5G_node_t *)_thing; /* Pointer to the object */

    herr_t      ret_value = SUCCEED;

    FUNC_ENTER_PACKAGE

    assert(sym);

    assert(sym->cache_info.type == H5AC_SNODE);

    /* Destroy symbol table node */

    if (H5G__node_free(sym) < 0)

        HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to destroy symbol table node");

done:

    FUNC_LEAVE_NOAPI(ret_value)

} /* end H5G__cache_node_free_icr() */