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/* Test races in the record locking code.
Copyright (C) 2001 Free Software Foundation, Inc.
Written by Neal H Walfield <neal@cs.uml.edu>
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, 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 the GNU Hurd. If not, see <http://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <error.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include "fs_U.h"
#include <hurd.h>
#include "io_U.h"
int main (int argc, char **argv)
{
error_t err;
struct flock64 lock;
mach_port_t rendezvous = MACH_PORT_NULL;
int fd;
int i;
mach_msg_type_number_t v;
int blocked = 0;
char buf[10] = "";
char *bufp;
if (argc != 4)
error (1, 0, "Usage: %s file start len", argv[0]);
lock.l_whence = SEEK_SET;
lock.l_start = atoi (argv[2]);
lock.l_len = atoi (argv[3]);
fd = file_name_lookup (argv[1], O_READ | O_WRITE | O_CREAT, 0666);
if (fd == MACH_PORT_NULL)
error (1, errno, "file_name_lookup");
for (i = 0; i < 10000; i ++)
{
lock.l_type = F_WRLCK;
err = file_record_lock (fd, F_SETLK64, &lock, rendezvous, MACH_MSG_TYPE_MAKE_SEND);
if (err)
{
blocked ++;
err = file_record_lock (fd, F_SETLKW64, &lock, rendezvous, MACH_MSG_TYPE_MAKE_SEND);
}
if (err)
error (1, err, "file_record_lock");
v = sizeof (buf);
bufp = buf;
io_read (fd, &bufp, &v, 0, v);
v = atoi (bufp);
sprintf (buf, "%d\n", v + 1);
v = 10;
io_write (fd, buf, sizeof (buf), 0, &v);
if (v == 0)
error (1, errno, "write (%d)", i);
lock.l_type = F_UNLCK;
file_record_lock (fd, F_SETLK64, &lock, rendezvous, MACH_MSG_TYPE_MAKE_SEND);
}
mach_port_deallocate (mach_task_self (), fd);
printf ("Was blocked %d times\n", blocked);
return 0;
}
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