int used [int];


syscall::open*:entry
{
 self->name=copyinstr(arg0);   
}

syscall::open*:return
/arg0 >= 0/
{
    fd[arg0] = self->name;
}

syscall::close*:entry
/used[arg0] == 1/
{
    printf ("Process %d closing non unmapped file %s\n", pid, fd[arg0]);
    used[arg0] = 0;
}
syscall::close*:entry
{
    fd[arg0] = 0;
}


syscall::mmap*:entry
/fd[arg4] != 0/
{
    self->mfd = arg4;
    printf ("Process %d mapped file %s\n", pid, fd[arg4]);
    jstack (30,8*1024);
}

syscall::mmap*:return
/self->mfd >= 0/
{
    mapped[arg0] = self->mfd;
    used[self->mfd] = 1;
}

syscall::munmap*:entry
/mapped[arg0] >= 0/
{
    used[mapped[arg0]] = 0;
    mapped[arg0] = 0;
}