uint32_t read_pty_slave(fs_node_t * node, uint32_t offset, uint32_t size, uint8_t *buffer) {
pty_t * pty = (pty_t *)node->device;
if (pty->tios.c_lflag & ICANON) {
return ring_buffer_read(pty->in, size, buffer);
} else {
if (pty->tios.c_cc[VMIN] == 0) {
return ring_buffer_read(pty->in, MIN(size, ring_buffer_unread(pty->in)), buffer);
} else {
return ring_buffer_read(pty->in, MIN(pty->tios.c_cc[VMIN], size), buffer);
}
}
}
size_t ring_buffer_read(ring_buffer_t * ring_buffer, size_t size, uint8_t * buffer) {
size_t collected = 0;
while (collected == 0) {
spin_lock(ring_buffer->lock);
while (ring_buffer_unread(ring_buffer) > 0 && collected < size) {
buffer[collected] = ring_buffer->buffer[ring_buffer->read_ptr];
ring_buffer_increment_read(ring_buffer);
collected++;
}
spin_unlock(ring_buffer->lock);
wakeup_queue(ring_buffer->wait_queue_writers);
if (collected == 0) {
if (sleep_on(ring_buffer->wait_queue_readers) && ring_buffer->internal_stop) {
ring_buffer->internal_stop = 0;
break;
}
}
}
wakeup_queue(ring_buffer->wait_queue_writers);
return collected;
}
size_t ring_buffer_size(fs_node_t * node) {
ring_buffer_t * ring_buffer = (ring_buffer_t *)node->device;
return ring_buffer_unread(ring_buffer);
}
int pty_available_output(fs_node_t * node) {
pty_t * pty = (pty_t *)node->device;
return ring_buffer_unread(pty->out);
}
