teragen_main.c

#define _OPEN_SOURCE 500

#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <getopt.h>
#include <mpi.h>
#include "terarec.h"


static long seeds[32] = {0L, 
        4160749568L, 
        4026531840L, 
        3892314112L,
        3758096384L,
        3623878656L,
        3489660928L,
        3355443200L,
        3221225472L,
        3087007744L,
        2952790016L,
        2818572288L,
        2684354560L,
        2550136832L,
        2415919104L,
        2281701376L,
        2147483648L,
        2013265920L,
        1879048192L,
        1744830464L,
        1610612736L,
        1476395008L,
        1342177280L,
        1207959552L,
        1073741824L,
        939524096L,
        805306368L,
        671088640L,
        536870912L,
        402653184L,
        268435456L,
        134217728L};

#define USAGE \
"usage:\n"                                                                     \
"  teragen [options]\n"                                                        \
"options:\n"                                                                   \
"  -f [filename]       Filename (Default: data.dat)\n"                         \
"  -c [count]         Elements to generate per processor (Default: 400)\n"\
"  -h                  Show this help message\n"

extern int zerocount;

int main (int argc, char *argv[]){
  int P, rank;
  MPI_Init (&argc, &argv);
  MPI_Comm_size (MPI_COMM_WORLD, &P);
  MPI_Comm_rank (MPI_COMM_WORLD, &rank);

  char * filename = "data.dat"; 
  long nrecs = 400;
  int c;

  while ((c = getopt (argc, argv, "hf:c:")) != -1){
    switch (c){
      case 'f':
        filename = optarg;
        break;
      case 'c':
        nrecs = atol(optarg);
        break;
      case 'h':
        fprintf(stderr, USAGE);
        exit(EXIT_SUCCESS);
      default:
        fprintf(stderr, USAGE);
        exit(EXIT_FAILURE);
    }
  }

  //Generating Data
  srand(seeds[rank % 32]);
  terarec_t *data = teraGenerate(rank * nrecs, nrecs);

  int fd;
  if(0 > (fd = open(filename, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR))){
    fprintf(stderr, "Failed to open file %s.", filename);
    exit(EXIT_FAILURE);
  }

  teraWriteToFile(fd, rank * nrecs, nrecs, data);

  close(fd);

  MPI_Finalize();

  return EXIT_SUCCESS;
}