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

const char* share_file = "/design/tmp/dsmith/share.txt";
char linebuf[1024];
int  buf_end_ptr;
int  curr_buf_ptr;

int get_line(char *outstring, int FD);

int main(int argc, char* argv[], char* envp[])
  {
  char *prog_name = argv[0];
  int i, status;
  int LOCKFD;
  flock_t f_struct;
  char input_line[80];
  char temp_line[80];
  char *user = getenv("USER");
  char *hostname = getenv("HOSTNAME");
  char *jobid    = getenv("LSB_JOBID");


/*

if (! -e $share_file)
  {
  if (system ("touch $share_file"))
    {
    die("can't create share file $share_file: $!");
    }
  }

*/

  for(i=1; i<=10; i++)
    {
    /* Open share file (in read + append) */

    if((LOCKFD = open(share_file, O_RDWR | O_CREAT)) <= 0)
      {
      fprintf(stderr, "%s - can't open shared file %s\n", prog_name, share_file);
      exit(1);
      }

    f_struct.l_type   = F_WRLCK;
    f_struct.l_whence = SEEK_SET;
    f_struct.l_start  = 0;
    f_struct.l_len    = 0;

    status = fcntl (LOCKFD, F_SETLK, &f_struct);

    if (status)
      {
      fprintf(stderr, "Another session of runtests is accessing the share file, waiting for if it to finish\n");
      status = fcntl (LOCKFD, F_SETLKW, &f_struct);
      }


    if (status)
      {
      fprintf(stderr, "something bad with shared file\n");
      exit(1);
      }

    buf_end_ptr = 0;
    curr_buf_ptr = 0;

    while(get_line(input_line, LOCKFD))
      {
      if (strstr(input_line, hostname))
	{

	fprintf (stdout, "Hello\n");
	}
      }

    sprintf (temp_line, "hostname %s jobid %s attempt %d\n", hostname, jobid, i);
    write (LOCKFD, temp_line, strlen(temp_line));

    f_struct.l_type   = F_UNLCK;
    f_struct.l_whence = SEEK_SET;
    f_struct.l_start  = 0;
    f_struct.l_len    = 0;

    status = fcntl (LOCKFD, F_SETLK, &f_struct);

    if (status)
      {
      fprintf(stderr, "something bad with unlocking share file\n");
      exit(1);
      }

    close(LOCKFD);
    }
    exit(0);
  }

int get_line(char *outstring, int FD)
  {
  char *lineptr = outstring;
  int index = 0;
  int line_read = 0;
  int num_read;
  int eol_not_found = 1;

  if (buf_end_ptr == 0)
    {
    buf_end_ptr = read(FD, linebuf, 1024);
    curr_buf_ptr = 0;
    if (buf_end_ptr < 0)
      {
      fprintf(stderr, "something bad with reading file\n");
      exit(1);
      }
    }
  while (eol_not_found)
    {
    if (curr_buf_ptr >= buf_end_ptr)
      {
      buf_end_ptr = read(FD, linebuf, 1024);
      curr_buf_ptr = 0;
      if (buf_end_ptr < 0)
	{
	fprintf(stderr, "something bad with reading file\n");
	exit(1);
	}
      }
    if (buf_end_ptr  == 0)
      {
      lineptr[0] = '\0';
      return line_read;
      }
    line_read = 1;
    if ((*lineptr = linebuf[curr_buf_ptr++]) == '\n')
      {
      lineptr[1] = '\0';
      return line_read;
      }
    lineptr++;
    }
  }