testcases/kernel/fs/fs_di/create_datafile.c

/*
 *
 *   Copyright (c) International Business Machines  Corp., 2003
 *
 *   This program is free software;  you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program;  if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

/*
 *  FILE        : create_datafile.c
 *  PURPOSE	: Creates a file of specified size.
 *  HISTORY	:
 *  	10/17/2003 Robbie Williamson
 *	  -Written
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>

/* set write buffer size to whatever floats your boat.  I usually use 1M */
#define BSIZE 1048576L

int
main(int argc, char *argv[])
{
   off_t i;
   long bufnum;
   char buf[BSIZE];
   off_t fd;

   if (argc != 3 || atoi(argv[1]) < 1)
   {
      printf("usage:\n\tcreate_file <# of %ld buffers to write> <name of file to create>\n\t ex. # create_file 10 /tmp/testfile\n",BSIZE);
      exit(3);
   }
   bufnum = strtol(argv[1],NULL,0);
   printf("Started building a %lu megabyte file\n",bufnum);
   buf[0]='A';
   for (i=1;i<BSIZE;i++)
      buf[i]=buf[i-1]+1;
   buf[BSIZE-1]='Z';

   if ((fd = creat(argv[2],0755)) == -1)
      perror("lftest: ");

   for (i=0;i<bufnum;i++)
   {
      if (write(fd,buf,BSIZE) == -1)
	 return -1;
      else
      {
	 printf(".");
	 fflush(stdout);
      }
      fsync(fd);
   }
   close(fd);
   printf("\nFinished building a %lu megabyte file\n",bufnum);
   return (0);
}