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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  * 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://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
  * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "H5PacketTable.h"

/*-------------------------------------------------------------------------
 * Packet Table Variable-Length Example
 *
 * Example program that creates a packet table and performs
 * writes and reads.
 *
 *-------------------------------------------------------------------------
 */

int main(void)
{
    herr_t err;     /* Return value from function calls */
    hid_t fileID;   /* HDF5 identifier for file */
    hsize_t count;  /* Number of records in table */
    int x;          /* Loop variable */

    /* This example has two different sizes of "record": longs and shorts */
    long longBuffer[5];
    short shortBuffer[5];

    /* Buffer of hvl_t structs to read back records */
    hvl_t readBuffer[5];

   /* Initialize buffers */
    for(x=0; x<5; x++)
    {
        longBuffer[x] = -x;
        shortBuffer[x] = x;
    }

    /* Create a new HDF5 file */
    fileID = H5Fcreate("PTcppexampleVL.h5", H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
    if(fileID <0)
        fprintf(stderr, "Couldn't create file.\n");

    /* Create a variable-length packet table. */
    VL_PacketTable ptable(fileID, "/examplePacketTable", 1);

    if(! ptable.IsValid())
        fprintf(stderr, "Unable to create packet table.");

    /* Append five packets to the packet table. */
    /* In C++, there is no need to package data into hvl_t structs. */
    err = ptable.AppendPacket( &(longBuffer[0]), sizeof(long));
    if(err < 0)
        fprintf(stderr, "Error adding record.");
    err = ptable.AppendPacket( &(shortBuffer[1]), sizeof(short));
    if(err < 0)
        fprintf(stderr, "Error adding record.");
    err = ptable.AppendPacket( &(longBuffer[2]), sizeof(long));
    if(err < 0)
        fprintf(stderr, "Error adding record.");
    err = ptable.AppendPacket( &(longBuffer[3]), sizeof(long));
    if(err < 0)
        fprintf(stderr, "Error adding record.");
    err = ptable.AppendPacket( &(shortBuffer[4]), sizeof(short));
    if(err < 0)
        fprintf(stderr, "Error adding record.");

    /* Get the number of packets in the packet table.  This should be five. */
    count = ptable.GetPacketCount(err);
    if(err < 0)
        fprintf(stderr, "Error getting packet count.");

    printf("Number of packets in packet table after five appends: %d\n", count);

    /* Initialize packet table's "current record" */
    ptable.ResetIndex();

    /* Iterate through packets, read each one back */
    for(int x=0; x<5; x++)
    {
        err = ptable.GetNextPacket( &(readBuffer[x]) );
        if(err < 0)
            fprintf(stderr, "Error reading record.");

        printf("Packet %d's length is %d.\n", x, readBuffer[x].len);
        if(readBuffer[x].len == sizeof(long))
            printf("Packet %d's value is %d.\n", x, *((long *) readBuffer[x].p) );
        else
            printf("Packet %d's value is %d.\n", x, *((short *) readBuffer[x].p) );
    }

    /* The packet table will close automatically when its object goes */
    /* out of scope.  */

    err = H5Fclose(fileID);
    if( err < 0 )
        fprintf(stderr, "Failed to close file.\n");

    return 0;
}