/* Small locking test program. Run 2 or more copies on the client
 * in an NFS mounted directory.
 * Invoke as "mlock N" to test with N files. I tried both N = 2
 * and N = 20 (which produces more conflicts, but the logs are
 * also harder to track). --okir
 */
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>

#define MAXFILES 255

static int fds[MAXFILES];

static void
lockit(int num, int len, int unlock)
{
    if (lockf(fds[num], unlock? F_ULOCK : F_LOCK, len) < 0) {
      fprintf(stderr, "Failed to %slock tfile%03d: %s\n",
      			unlock? "un" : "", num, strerror(errno));
      exit(1);
    }
}

int
main(int argc, char **argv)
{
    int	nfiles = 0, counter, rounds = 0;

    if (argc >= 2)
        nfiles = atoi(argv[1]);

    if (nfiles <= 0 || nfiles > MAXFILES)
      nfiles = MAXFILES;

    setvbuf(stdout, NULL, _IONBF, 0);
    setvbuf(stderr, NULL, _IONBF, 0);

    printf("Opening %d files...  ", nfiles);
    for ( counter = 0; counter < nfiles; counter++ ) {
      char filename[64];

      sprintf( filename, "tfile%03d", counter );
      fds[counter] = open(filename, O_CREAT | O_RDWR, 0644);
      if (fds[counter] < 0) {
	perror(filename);
	return 1;
      }
    }
    printf("done.\n");

    while (1) {
      printf("\r%d", rounds++);

      for (counter = 0; counter < nfiles; counter++)
        lockit(counter, 0, 0);

      /* Change 0 to 1 in the lockit call to test for the
       * lock all/unlock at offset 1 bug */
      for (counter = 0; counter < nfiles; counter++)
        lockit(counter, 0, 1);
    }

    exit(0);
}