void hardware_dispatch_request(Packet *request) {
char packet_signature[PACKET_MAX_SIGNATURE_LENGTH];
int i;
Stack *stack;
int rc;
bool dispatched = false;
if (_stacks.count == 0) {
log_packet_debug("No stacks connected, dropping request (%s)",
packet_get_request_signature(packet_signature, request));
return;
}
if (request->header.uid == 0) {
log_packet_debug("Broadcasting request (%s) to %d stack(s)",
packet_get_request_signature(packet_signature, request),
_stacks.count);
// broadcast to all stacks
for (i = 0; i < _stacks.count; ++i) {
stack = *(Stack **)array_get(&_stacks, i);
stack_dispatch_request(stack, request, true);
}
} else {
log_packet_debug("Dispatching request (%s) to %d stack(s)",
packet_get_request_signature(packet_signature, request),
_stacks.count);
// dispatch to all stacks, not only the first one that might claim to
// know the UID
for (i = 0; i < _stacks.count; ++i) {
stack = *(Stack **)array_get(&_stacks, i);
rc = stack_dispatch_request(stack, request, false);
if (rc < 0) {
continue;
} else if (rc > 0) {
dispatched = true;
}
}
if (dispatched) {
return;
}
log_packet_debug("Broadcasting request because UID is currently unknown");
// broadcast to all stacks, as no stack claimed to know the UID
for (i = 0; i < _stacks.count; ++i) {
stack = *(Stack **)array_get(&_stacks, i);
stack_dispatch_request(stack, request, true);
}
}
}
static void client_handle_request(Client *client, Packet *request) {
char packet_signature[PACKET_MAX_SIGNATURE_LENGTH];
EmptyResponse response;
// handle requests meant for brickd
if (uint32_from_le(request->header.uid) == UID_BRICK_DAEMON) {
// add as pending request if response is expected
if (packet_header_get_response_expected(&request->header)) {
network_client_expects_response(client, request);
}
if (request->header.function_id == FUNCTION_GET_AUTHENTICATION_NONCE) {
if (request->header.length != sizeof(GetAuthenticationNonceRequest)) {
log_error("Received authentication-nonce request (%s) from client ("CLIENT_SIGNATURE_FORMAT") with wrong length, disconnecting client",
packet_get_request_signature(packet_signature, request),
client_expand_signature(client));
client->disconnected = true;
return;
}
client_handle_get_authentication_nonce_request(client, (GetAuthenticationNonceRequest *)request);
} else if (request->header.function_id == FUNCTION_AUTHENTICATE) {
if (request->header.length != sizeof(AuthenticateRequest)) {
log_error("Received authenticate request (%s) from client ("CLIENT_SIGNATURE_FORMAT") with wrong length, disconnecting client",
packet_get_request_signature(packet_signature, request),
client_expand_signature(client));
client->disconnected = true;
return;
}
client_handle_authenticate_request(client, (AuthenticateRequest *)request);
} else {
response.header = request->header;
response.header.length = sizeof(response);
packet_header_set_error_code(&response.header,
PACKET_E_FUNCTION_NOT_SUPPORTED);
client_dispatch_response(client, NULL, (Packet *)&response, false, false);
}
} else if (client->authentication_state == CLIENT_AUTHENTICATION_STATE_DISABLED ||
client->authentication_state == CLIENT_AUTHENTICATION_STATE_DONE) {
// add as pending request if response is expected...
if (packet_header_get_response_expected(&request->header)) {
network_client_expects_response(client, request);
}
// ...then dispatch it to the hardware
hardware_dispatch_request(request);
} else {
log_packet_debug("Client ("CLIENT_SIGNATURE_FORMAT") is not authenticated, dropping request (%s)",
client_expand_signature(client),
packet_get_request_signature(packet_signature, request));
}
}
// New packet from brickd event loop is queued to be written to stack via SPI
static int red_stack_dispatch_to_spi(Stack *stack, Packet *request, Recipient *recipient) {
REDStackPacket *queued_request;
(void)stack;
if (request->header.uid == 0) {
// UID = 0 -> Broadcast to all UIDs
uint8_t is;
for (is = 0; is < _red_stack.slave_num; is++) {
mutex_lock(&_red_stack.slaves[is].packet_queue_mutex);
queued_request = queue_push(&_red_stack.slaves[is].packet_to_spi_queue);
queued_request->status = RED_STACK_PACKET_STATUS_ADDED;
queued_request->slave = &_red_stack.slaves[is];
memcpy(&queued_request->packet, request, request->header.length);
mutex_unlock(&_red_stack.slaves[is].packet_queue_mutex);
log_packet_debug("Request is queued to be broadcast to slave %d (%s)",
is, packet_get_request_signature(packet_signature, request));
}
} else if (recipient != NULL) {
// Get slave for recipient opaque (== stack_address)
REDStackSlave *slave = &_red_stack.slaves[recipient->opaque];
mutex_lock(&(slave->packet_queue_mutex));
queued_request = queue_push(&(slave->packet_to_spi_queue));
queued_request->status = RED_STACK_PACKET_STATUS_ADDED;
queued_request->slave = slave;
memcpy(&queued_request->packet, request, request->header.length);
mutex_unlock(&(slave->packet_queue_mutex));
log_packet_debug("Packet is queued to be send to slave %d over SPI (%s)",
slave->stack_address,
packet_get_request_signature(packet_signature, request));
}
return 0;
}
void network_client_expects_response(Client *client, Packet *request) {
PendingRequest *pending_request;
char packet_signature[PACKET_MAX_SIGNATURE_LENGTH];
if (client->pending_request_count >= CLIENT_MAX_PENDING_REQUESTS) {
log_warn("Pending requests list for client ("CLIENT_SIGNATURE_FORMAT") is full, dropping %d pending request(s)",
client_expand_signature(client),
client->pending_request_count - CLIENT_MAX_PENDING_REQUESTS + 1);
while (client->pending_request_count >= CLIENT_MAX_PENDING_REQUESTS) {
pending_request = containerof(client->pending_request_sentinel.next, PendingRequest, client_node);
pending_request_remove_and_free(pending_request);
}
}
pending_request = calloc(1, sizeof(PendingRequest));
if (pending_request == NULL) {
log_error("Could not allocate pending request: %s (%d)",
get_errno_name(ENOMEM), ENOMEM);
return;
}
node_reset(&pending_request->global_node);
node_insert_before(&_pending_request_sentinel, &pending_request->global_node);
node_reset(&pending_request->client_node);
node_insert_before(&client->pending_request_sentinel, &pending_request->client_node);
++client->pending_request_count;
pending_request->client = client;
pending_request->zombie = NULL;
memcpy(&pending_request->header, &request->header, sizeof(PacketHeader));
#ifdef BRICKD_WITH_PROFILING
pending_request->arrival_time = microseconds();
#endif
log_packet_debug("Added pending request (%s) for client ("CLIENT_SIGNATURE_FORMAT")",
packet_get_request_signature(packet_signature, request),
client_expand_signature(client));
}
// New packet from brickd event loop is queued to be written to BrickletStack via SPI
static int bricklet_stack_dispatch_to_spi(Stack *stack, Packet *request, Recipient *recipient) {
BrickletStack *bricklet_stack = (BrickletStack*)stack;
Packet *queued_request;
if((request->header.uid != 0) && (recipient == NULL)) {
return 0;
}
if (!bricklet_stack->data_seen) {
return 0;
}
mutex_lock(&bricklet_stack->request_queue_mutex);
queued_request = queue_push(&bricklet_stack->request_queue);
memcpy(queued_request, request, request->header.length);
mutex_unlock(&bricklet_stack->request_queue_mutex);
log_packet_debug("Packet is queued to be send over SPI (%s)",
packet_get_request_signature(packet_signature, request));
return 0;
}
void client_dispatch_response(Client *client, PendingRequest *pending_request,
Packet *response, bool force, bool ignore_authentication) {
Node *pending_request_client_node = NULL;
int enqueued = 0;
#ifdef BRICKD_WITH_PROFILING
uint64_t elapsed;
#endif
if (!ignore_authentication &&
client->authentication_state != CLIENT_AUTHENTICATION_STATE_DISABLED &&
client->authentication_state != CLIENT_AUTHENTICATION_STATE_DONE) {
log_packet_debug("Ignoring non-authenticated client ("CLIENT_SIGNATURE_FORMAT")",
client_expand_signature(client));
goto cleanup;
}
// find matching pending request if not forced and no pending request is
// already given. do this before the disconnect check to ensure that even
// for a disconnected client the pending request list is updated correctly
if (!force && pending_request == NULL) {
pending_request_client_node = client->pending_request_sentinel.next;
while (pending_request_client_node != &client->pending_request_sentinel) {
pending_request = containerof(pending_request_client_node, PendingRequest, client_node);
if (packet_is_matching_response(response, &pending_request->header)) {
break;
}
pending_request_client_node = pending_request_client_node->next;
}
if (pending_request_client_node == &client->pending_request_sentinel) {
pending_request = NULL;
goto cleanup;
}
}
if (client->disconnected) {
log_debug("Ignoring disconnected client ("CLIENT_SIGNATURE_FORMAT")",
client_expand_signature(client));
goto cleanup;
}
if (force || pending_request != NULL) {
enqueued = writer_write(&client->response_writer, response);
if (enqueued < 0) {
goto cleanup;
}
if (force) {
log_packet_debug("Forced to %s response to client ("CLIENT_SIGNATURE_FORMAT")",
enqueued ? "enqueue" : "send", client_expand_signature(client));
} else {
#ifdef BRICKD_WITH_PROFILING
elapsed = microseconds() - pending_request->arrival_time;
log_packet_debug("%s response to client ("CLIENT_SIGNATURE_FORMAT"), was requested %u.%03u msec ago, %d request(s) still pending",
enqueued ? "Enqueued" : "Sent", client_expand_signature(client),
(unsigned int)(elapsed / 1000), (unsigned int)(elapsed % 1000),
client->pending_request_count - 1);
#else
log_packet_debug("%s response to client ("CLIENT_SIGNATURE_FORMAT"), %d request(s) still pending",
enqueued ? "Enqueued" : "Sent", client_expand_signature(client),
client->pending_request_count - 1);
#endif
}
}
cleanup:
if (pending_request != NULL) {
pending_request_remove_and_free(pending_request);
}
}
static void client_handle_read(void *opaque) {
Client *client = opaque;
int length;
const char *message = NULL;
char packet_signature[PACKET_MAX_SIGNATURE_LENGTH];
length = io_read(client->io, (uint8_t *)&client->request + client->request_used,
sizeof(Packet) - client->request_used);
if (length == 0) {
log_info("Client ("CLIENT_SIGNATURE_FORMAT") disconnected by peer",
client_expand_signature(client));
client->disconnected = true;
return;
}
if (length < 0) {
if (length == IO_CONTINUE) {
// no actual data received
} else if (errno_interrupted()) {
log_debug("Receiving from client ("CLIENT_SIGNATURE_FORMAT") was interrupted, retrying",
client_expand_signature(client));
} else if (errno_would_block()) {
log_debug("Receiving from client ("CLIENT_SIGNATURE_FORMAT") would block, retrying",
client_expand_signature(client));
} else {
log_error("Could not receive from client ("CLIENT_SIGNATURE_FORMAT"), disconnecting client: %s (%d)",
client_expand_signature(client), get_errno_name(errno), errno);
client->disconnected = true;
}
return;
}
client->request_used += length;
while (!client->disconnected && client->request_used > 0) {
if (client->request_used < (int)sizeof(PacketHeader)) {
// wait for complete header
break;
}
if (!client->request_header_checked) {
if (!packet_header_is_valid_request(&client->request.header, &message)) {
// FIXME: include packet_get_content_dump output in the error message
log_error("Received invalid request (%s) from client ("CLIENT_SIGNATURE_FORMAT"), disconnecting client: %s",
packet_get_request_signature(packet_signature, &client->request),
client_expand_signature(client), message);
client->disconnected = true;
return;
}
client->request_header_checked = true;
}
length = client->request.header.length;
if (client->request_used < length) {
// wait for complete packet
break;
}
if (client->request.header.function_id == FUNCTION_DISCONNECT_PROBE) {
log_packet_debug("Received disconnect probe from client ("CLIENT_SIGNATURE_FORMAT"), dropping request",
client_expand_signature(client));
} else {
log_packet_debug("Received request (%s) from client ("CLIENT_SIGNATURE_FORMAT")",
packet_get_request_signature(packet_signature, &client->request),
client_expand_signature(client));
client_handle_request(client, &client->request);
}
memmove(&client->request, (uint8_t *)&client->request + length,
client->request_used - length);
client->request_used -= length;
client->request_header_checked = false;
}
}
void network_dispatch_response(Packet *response) {
EnumerateCallback *enumerate_callback;
char packet_signature[PACKET_MAX_SIGNATURE_LENGTH];
int i;
Client *client;
Node *pending_request_global_node;
PendingRequest *pending_request;
if (packet_header_get_sequence_number(&response->header) == 0) {
if (response->header.function_id == CALLBACK_ENUMERATE) {
enumerate_callback = (EnumerateCallback *)response;
if (enumerate_callback->enumeration_type == ENUMERATION_TYPE_CONNECTED ||
enumerate_callback->enumeration_type == ENUMERATION_TYPE_DISCONNECTED) {
network_drop_pending_requests(response->header.uid);
}
}
if (_clients.count == 0) {
log_packet_debug("No clients connected, dropping %s (%s)",
packet_get_response_type(response),
packet_get_response_signature(packet_signature, response));
return;
}
log_packet_debug("Broadcasting %s (%s) to %d client(s)",
packet_get_response_type(response),
packet_get_response_signature(packet_signature, response),
_clients.count);
for (i = 0; i < _clients.count; ++i) {
client = array_get(&_clients, i);
client_dispatch_response(client, NULL, response, true, false);
}
} else if (_clients.count + _zombies.count > 0) {
log_packet_debug("Dispatching response (%s) to %d client(s) and %d zombies(s)",
packet_get_response_signature(packet_signature, response),
_clients.count, _zombies.count);
pending_request_global_node = _pending_request_sentinel.next;
while (pending_request_global_node != &_pending_request_sentinel) {
pending_request = containerof(pending_request_global_node,
PendingRequest, global_node);
if (packet_is_matching_response(response, &pending_request->header)) {
if (pending_request->client != NULL) {
client_dispatch_response(pending_request->client, pending_request,
response, false, false);
} else {
zombie_dispatch_response(pending_request->zombie, pending_request);
}
return;
}
pending_request_global_node = pending_request_global_node->next;
}
log_warn("Broadcasting response (%s) because no client/zombie has a matching pending request",
packet_get_response_signature(packet_signature, response));
for (i = 0; i < _clients.count; ++i) {
client = array_get(&_clients, i);
client_dispatch_response(client, NULL, response, true, false);
}
} else {
log_packet_debug("No clients/zombies connected, dropping response (%s)",
packet_get_response_signature(packet_signature, response));
}
}
static void LIBUSB_CALL usb_transfer_wrapper(struct libusb_transfer *handle) {
USBTransfer *usb_transfer = handle->user_data;
if (!usb_transfer->submitted) {
log_error("%s transfer %p (%p) returned from %s, but was not submitted before",
usb_transfer_get_type_name(usb_transfer->type, true),
usb_transfer, handle, usb_transfer->usb_stack->base.name);
return;
}
usb_transfer->submitted = false;
usb_transfer->completed = true;
if (handle->status == LIBUSB_TRANSFER_CANCELLED) {
usb_transfer->usb_stack->expecting_disconnect = true;
log_debug("%s transfer %p (%p) for %s was cancelled, marking device as about to be removed",
usb_transfer_get_type_name(usb_transfer->type, true),
usb_transfer, handle, usb_transfer->usb_stack->base.name);
return;
} else if (handle->status == LIBUSB_TRANSFER_NO_DEVICE) {
usb_transfer->usb_stack->expecting_disconnect = true;
log_debug("%s transfer %p (%p) for %s was aborted, device got disconnected",
usb_transfer_get_type_name(usb_transfer->type, true),
usb_transfer, handle, usb_transfer->usb_stack->base.name);
return;
} else if (handle->status == LIBUSB_TRANSFER_STALL) {
// unplugging a RED Brick from Windows results in a stalled transfer
// followed by read transfers returning garbage data and transfer
// submission errors. all this happens before the unplug event for
// the device is received. avoid logging pointless error messages
// about garbage data and transfer submission errors by detecting this
// condition here and deactivating the device
if (usb_transfer->usb_stack->expecting_read_stall_before_removal &&
usb_transfer->type == USB_TRANSFER_TYPE_READ) {
usb_transfer->usb_stack->expecting_read_stall_before_removal = false;
usb_transfer->usb_stack->expecting_disconnect = true;
log_debug("%s transfer %p (%p) for %s got stalled as expected before device removal, marking device as about to be removed",
usb_transfer_get_type_name(usb_transfer->type, true),
usb_transfer, handle, usb_transfer->usb_stack->base.name);
} else {
log_warn("%s transfer %p (%p) for %s got stalled",
usb_transfer_get_type_name(usb_transfer->type, true),
usb_transfer, handle, usb_transfer->usb_stack->base.name);
// FIXME: maybe use libusb_clear_halt to clear halt condition?
}
return;
} else if (handle->status != LIBUSB_TRANSFER_COMPLETED) {
log_warn("%s transfer %p (%p) returned with an error from %s: %s (%d)",
usb_transfer_get_type_name(usb_transfer->type, true), usb_transfer,
handle, usb_transfer->usb_stack->base.name,
usb_transfer_get_status_name(handle->status), handle->status);
} else {
log_packet_debug("%s transfer %p (%p) returned successfully from %s%s",
usb_transfer_get_type_name(usb_transfer->type, true),
usb_transfer, handle, usb_transfer->usb_stack->base.name,
usb_transfer->cancelled
? ", but it was cancelled in the meantime"
: (usb_transfer->usb_stack->expecting_disconnect
? ", but the corresponding USB device is about to be removed"
: ""));
if (usb_transfer->cancelled ||
usb_transfer->usb_stack->expecting_disconnect) {
return;
}
if (usb_transfer->function != NULL) {
usb_transfer->function(usb_transfer);
}
}
if (usb_transfer->type == USB_TRANSFER_TYPE_READ &&
!usb_transfer->cancelled &&
!usb_transfer->usb_stack->expecting_disconnect) {
usb_transfer_submit(usb_transfer);
}
}
int usb_transfer_submit(USBTransfer *usb_transfer) {
uint8_t endpoint;
int length;
int rc;
if (usb_transfer->submitted) {
log_error("%s transfer %p (%p) is already submitted for %s",
usb_transfer_get_type_name(usb_transfer->type, true), usb_transfer,
usb_transfer->handle, usb_transfer->usb_stack->base.name);
return -1;
}
switch (usb_transfer->type) {
case USB_TRANSFER_TYPE_READ:
endpoint = usb_transfer->usb_stack->endpoint_in;
length = sizeof(Packet);
break;
case USB_TRANSFER_TYPE_WRITE:
endpoint = usb_transfer->usb_stack->endpoint_out;
length = usb_transfer->packet.header.length;
break;
default:
log_error("Transfer for %s has invalid type",
usb_transfer->usb_stack->base.name);
return -1;
}
usb_transfer->submitted = true;
libusb_fill_bulk_transfer(usb_transfer->handle,
usb_transfer->usb_stack->device_handle,
endpoint,
(unsigned char *)&usb_transfer->packet,
length,
usb_transfer_wrapper,
usb_transfer,
0);
rc = libusb_submit_transfer(usb_transfer->handle);
if (rc < 0) {
log_error("Could not submit %s transfer %p (%p) to %s: %s (%d)",
usb_transfer_get_type_name(usb_transfer->type, false), usb_transfer,
usb_transfer->handle, usb_transfer->usb_stack->base.name,
usb_get_error_name(rc), rc);
usb_transfer->submitted = false;
return -1;
}
log_packet_debug("Submitted %s transfer %p (%p) for %u bytes to %s",
usb_transfer_get_type_name(usb_transfer->type, false),
usb_transfer, usb_transfer->handle, length,
usb_transfer->usb_stack->base.name);
return 0;
}
// Main SPI loop. This runs independently from the brickd event thread.
// Data between RED Brick and SPI slave is exchanged every 500us.
// If there is no data to be send, we cycle through the slaves and request
// data. If there is data to be send the slave that ought to receive
// the data gets priority. This can greatly reduce latency in a big stack.
static void red_stack_spi_thread(void *opaque) {
REDStackPacket *packet_to_spi = NULL;
uint8_t stack_address_cycle;
int ret;
(void)opaque;
do {
stack_address_cycle = 0;
_red_stack_reset_detected = 0;
_red_stack.slave_num = 0;
red_stack_spi_create_routing_table();
_red_stack_spi_thread_running = false;
if (_red_stack.slave_num > 0) {
_red_stack_spi_thread_running = true;
}
// Ignore resets that we received in the meantime to prevent race conditions.
_red_stack_reset_detected = 0;
while (_red_stack_spi_thread_running) {
REDStackSlave *slave = &_red_stack.slaves[stack_address_cycle];
REDStackPacket *request = NULL;
memset(&_red_stack.packet_from_spi, 0, sizeof(Packet));
// Get packet from queue. The queue contains that are to be
// send over SPI. It is filled through from the main brickd
// event thread, so we have to make sure that there is not race
// condition.
if(slave->next_packet_empty) {
slave->next_packet_empty = false;
packet_to_spi = NULL;
} else {
mutex_lock(&(slave->packet_queue_mutex));
packet_to_spi = queue_peek(&slave->packet_to_spi_queue);
mutex_unlock(&(slave->packet_queue_mutex));
}
stack_address_cycle++;
if (stack_address_cycle >= _red_stack.slave_num) {
stack_address_cycle = 0;
}
// Set request if we have a packet to send
if (packet_to_spi != NULL) {
log_packet_debug("Packet will now be send over SPI (%s)",
packet_get_request_signature(packet_signature, &packet_to_spi->packet));
request = packet_to_spi;
}
ret = red_stack_spi_transceive_message(request, &_red_stack.packet_from_spi, slave);
if ((ret & RED_STACK_TRANSCEIVE_RESULT_MASK_SEND) == RED_STACK_TRANSCEIVE_RESULT_SEND_OK) {
if ((!((ret & RED_STACK_TRANSCEIVE_RESULT_MASK_READ) == RED_STACK_TRANSCEIVE_RESULT_READ_ERROR))) {
// If we send a packet it must have come from the queue, so we can
// pop it from the queue now.
// If the sending didn't work (for whatever reason), we don't pop it
// and therefore we will automatically try to send it again in the next cycle.
mutex_lock(&(slave->packet_queue_mutex));
queue_pop(&slave->packet_to_spi_queue, NULL);
mutex_unlock(&(slave->packet_queue_mutex));
}
}
// If we received a packet, we will dispatch it immediately.
// We have some time until we try the next SPI communication anyway.
if ((ret & RED_STACK_TRANSCEIVE_RESULT_MASK_READ) == RED_STACK_TRANSCEIVE_RESULT_READ_OK) {
// TODO: Check again if packet is valid?
// We did already check the hash.
// Before the dispatching we insert the stack position into an enumerate message
red_stack_spi_insert_position(slave);
red_stack_spi_request_dispatch_response_event();
// Wait until message is dispatched, so we don't overwrite it
// accidentally.
semaphore_acquire(&_red_stack_dispatch_packet_from_spi_semaphore);
}
SLEEP_NS(0, 1000*_red_stack_spi_poll_delay);
}
if (_red_stack.slave_num == 0) {
pthread_mutex_lock(&_red_stack_wait_for_reset_mutex);
// Use helper to be save against spurious wakeups
_red_stack_wait_for_reset_helper = 0;
while (_red_stack_wait_for_reset_helper == 0) {
pthread_cond_wait(&_red_stack_wait_for_reset_cond, &_red_stack_wait_for_reset_mutex);
}
pthread_mutex_unlock(&_red_stack_wait_for_reset_mutex);
}
if (_red_stack_reset_detected > 0) {
red_stack_spi_handle_reset();
}
} while (_red_stack_reset_detected > 0);
}
// If data should just be polled, set packet_send to NULL.
//
// If no packet is received from slave the length in packet_recv will be set to 0,
// the exact reason for that is encoded in the return value.
//
// For the return value see RED_STACK_TRANSCEIVE_RESULT_* at the top of this file.
static int red_stack_spi_transceive_message(REDStackPacket *packet_send, Packet *packet_recv, REDStackSlave *slave) {
int retval = 0;
uint8_t length, length_send;
uint8_t checksum;
int rc;
uint8_t sequence_number_master = 0xFF;
uint8_t sequence_number_slave = 0xFF;
uint8_t tx[RED_STACK_SPI_PACKET_SIZE] = {0};
uint8_t rx[RED_STACK_SPI_PACKET_SIZE] = {0};
// We assume that we don't receive anything. If we receive a packet the
// length will be overwritten again
packet_recv->header.length = 0;
// Preamble is always the same
tx[RED_STACK_SPI_PREAMBLE] = RED_STACK_SPI_PREAMBLE_VALUE;
if (packet_send == NULL) {
// If packet_send is NULL
// we send a message with empty payload (4 byte)
tx[RED_STACK_SPI_LENGTH] = RED_STACK_SPI_PACKET_EMPTY_SIZE;
retval = RED_STACK_TRANSCEIVE_RESULT_SEND_NONE;
} else if (slave->status == RED_STACK_SLAVE_STATUS_AVAILABLE) {
length = packet_send->packet.header.length;
if (length > sizeof(Packet)) {
retval |= RED_STACK_TRANSCEIVE_RESULT_SEND_ERROR;
log_error("Send length is greater then allowed (actual: %d > maximum: %d)",
length, (int)sizeof(Packet));
goto ret;
}
retval = RED_STACK_TRANSCEIVE_DATA_SEND;
tx[RED_STACK_SPI_LENGTH] = length + RED_STACK_SPI_PACKET_EMPTY_SIZE;
memcpy(tx+2, &packet_send->packet, length);
} else {
retval = RED_STACK_TRANSCEIVE_RESULT_SEND_ERROR;
log_error("Slave with stack address %d is not present in stack", slave->stack_address);
goto ret;
}
length = tx[RED_STACK_SPI_LENGTH];
// Set master and slave sequence number
tx[RED_STACK_SPI_INFO(length)] = slave->sequence_number_master | slave->sequence_number_slave;
// Calculate checksum
tx[RED_STACK_SPI_CHECKSUM(length)] = red_stack_spi_calculate_pearson_hash(tx, length-1);
struct spi_ioc_transfer spi_transfer = {
.tx_buf = (unsigned long)&tx,
.rx_buf = (unsigned long)&rx,
.len = RED_STACK_SPI_PACKET_SIZE,
};
red_stack_spi_select(slave);
rc = ioctl(_red_stack_spi_fd, SPI_IOC_MESSAGE(1), &spi_transfer);
red_stack_spi_deselect(slave);
if (rc < 0) {
// Overwrite current return status with error,
// it seems ioctl itself didn't work.
retval = RED_STACK_TRANSCEIVE_RESULT_SEND_ERROR | RED_STACK_TRANSCEIVE_RESULT_READ_ERROR;
if(packet_send == NULL) {
slave->next_packet_empty = true;
}
log_error("ioctl failed: %s (%d)", get_errno_name(errno), errno);
goto ret;
}
length_send = rc;
if (length_send != RED_STACK_SPI_PACKET_SIZE) {
// Overwrite current return status with error,
// it seems ioctl itself didn't work.
retval = RED_STACK_TRANSCEIVE_RESULT_SEND_ERROR | RED_STACK_TRANSCEIVE_RESULT_READ_ERROR;
if(packet_send == NULL) {
slave->next_packet_empty = true;
}
log_error("ioctl has unexpected result (actual: %d != expected: %d)",
length_send, RED_STACK_SPI_PACKET_SIZE);
goto ret;
}
if (rx[RED_STACK_SPI_PREAMBLE] != RED_STACK_SPI_PREAMBLE_VALUE) {
// Do not log by default, an "unproper preamble" is part of the protocol
// if the slave is too busy to fill the DMA buffers fast enough
// log_error("Received packet without proper preamble (actual: %d != expected: %d)",
// rx[RED_STACK_SPI_PREAMBLE], RED_STACK_SPI_PREAMBLE_VALUE);
retval = (retval & (~RED_STACK_TRANSCEIVE_RESULT_MASK_READ)) | RED_STACK_TRANSCEIVE_RESULT_READ_ERROR;
if(packet_send == NULL) {
slave->next_packet_empty = true;
}
goto ret;
}
// Check length
length = rx[RED_STACK_SPI_LENGTH];
if ((length != RED_STACK_SPI_PACKET_EMPTY_SIZE) &&
((length < (RED_STACK_SPI_PACKET_EMPTY_SIZE + sizeof(PacketHeader))) ||
(length > RED_STACK_SPI_PACKET_SIZE))) {
log_error("Received packet with malformed length: %d", length);
retval = (retval & (~RED_STACK_TRANSCEIVE_RESULT_MASK_READ)) | RED_STACK_TRANSCEIVE_RESULT_READ_ERROR;
if(packet_send == NULL) {
slave->next_packet_empty = true;
}
goto ret;
}
// Calculate and check checksum
checksum = red_stack_spi_calculate_pearson_hash(rx, length-1);
if (checksum != rx[RED_STACK_SPI_CHECKSUM(length)]) {
log_error("Received packet with wrong checksum (actual: %x != expected: %x)",
checksum, rx[RED_STACK_SPI_CHECKSUM(length)]);
retval = (retval & (~RED_STACK_TRANSCEIVE_RESULT_MASK_READ)) | RED_STACK_TRANSCEIVE_RESULT_READ_ERROR;
if(packet_send == NULL) {
slave->next_packet_empty = true;
}
goto ret;
}
// If we send data and the master sequence number matches to the one
// set in the packet we know that the slave received the packet!
if ((packet_send != NULL) /*&& (packet_send->status == RED_STACK_PACKET_STATUS_SEQUENCE_NUMBER_SET)*/) {
sequence_number_master = rx[RED_STACK_SPI_INFO(length)] & RED_STACK_SPI_INFO_SEQUENCE_MASTER_MASK;
if (sequence_number_master == slave->sequence_number_master) {
retval = (retval & (~RED_STACK_TRANSCEIVE_RESULT_MASK_SEND)) | RED_STACK_TRANSCEIVE_RESULT_SEND_OK;
// Increase sequence number for next packet
red_stack_increase_master_sequence_number(slave);
}
} else {
// If we didn't send anything we can always increase the sequence number,
// it doesn't matter if the slave actually received it.
red_stack_increase_master_sequence_number(slave);
}
// If the slave sequence number matches we already processed this packet
sequence_number_slave = rx[RED_STACK_SPI_INFO(length)] & RED_STACK_SPI_INFO_SEQUENCE_SLAVE_MASK;
if (sequence_number_slave == slave->sequence_number_slave) {
retval = (retval & (~RED_STACK_TRANSCEIVE_RESULT_MASK_READ)) | RED_STACK_TRANSCEIVE_RESULT_READ_NONE;
} else {
// Otherwise we save the new sequence number
slave->sequence_number_slave = sequence_number_slave;
if (length == RED_STACK_SPI_PACKET_EMPTY_SIZE) {
// Do not log by default, will produce 2000 log entries per second
// log_packet_debug("Received empty packet over SPI (w/ header)");
retval = (retval & (~RED_STACK_TRANSCEIVE_RESULT_MASK_READ)) | RED_STACK_TRANSCEIVE_RESULT_READ_NONE;
} else {
// Everything seems OK, we can copy to buffer
memcpy(packet_recv, rx+2, length - RED_STACK_SPI_PACKET_EMPTY_SIZE);
log_packet_debug("Received packet over SPI (%s)",
packet_get_response_signature(packet_signature, packet_recv));
retval = (retval & (~RED_STACK_TRANSCEIVE_RESULT_MASK_READ)) | RED_STACK_TRANSCEIVE_RESULT_READ_OK;
retval |= RED_STACK_TRANSCEIVE_DATA_RECEIVED;
}
}
ret:
return retval;
}
// Creates the "routing table", which is just the
// array of REDStackSlave structures.
static void red_stack_spi_create_routing_table(void) {
char base58[BASE58_MAX_LENGTH];
int tries, ret, i;
uint8_t stack_address = 0;
uint8_t uid_counter = 0;
log_debug("Starting to discover SPI stack slaves");
while (stack_address < RED_STACK_SPI_MAX_SLAVES) {
REDStackSlave *slave = &_red_stack.slaves[stack_address];
Packet packet;
StackEnumerateResponse *response;
REDStackPacket red_stack_packet = {
slave,
{{
0, // UID 0
sizeof(StackEnumerateRequest),
FUNCTION_STACK_ENUMERATE,
0x08, // Return expected
0
}, {0}, {0}},
RED_STACK_PACKET_STATUS_ADDED,
};
// We have to assume that the slave is available
slave->status = RED_STACK_SLAVE_STATUS_AVAILABLE;
// Send stack enumerate request
for (tries = 0; tries < RED_STACK_SPI_ROUTING_TRIES; tries++) {
ret = red_stack_spi_transceive_message(&red_stack_packet, &packet, slave);
if ((ret & RED_STACK_TRANSCEIVE_RESULT_MASK_SEND) == RED_STACK_TRANSCEIVE_RESULT_SEND_OK) {
break;
}
SLEEP_NS(0, RED_STACK_SPI_ROUTING_WAIT); // Give slave some more time
}
if (tries == RED_STACK_SPI_ROUTING_TRIES) {
// Slave does not seem to be available,
slave->status = RED_STACK_SLAVE_STATUS_ABSENT;
// This means that there can't be any more slaves above
// and we are actually done here already!
break;
}
// Receive stack enumerate response
for (tries = 0; tries < RED_STACK_SPI_ROUTING_TRIES; tries++) {
// We first check if we already received an answer before we try again
if ((ret & RED_STACK_TRANSCEIVE_RESULT_MASK_READ) == RED_STACK_TRANSCEIVE_RESULT_READ_OK) {
break;
}
// Here we sleep before transceive so that there is some time
// between the sending of stack enumerate and the receiving
// of the answer
SLEEP_NS(0, RED_STACK_SPI_ROUTING_WAIT); // Give slave some more time
ret = red_stack_spi_transceive_message(NULL, &packet, slave);
}
if (tries == RED_STACK_SPI_ROUTING_TRIES) {
// Slave does not seem to be available,
slave->status = RED_STACK_SLAVE_STATUS_ABSENT;
// This means that there can't be any more slaves above
// and we are actually done here already!
break;
}
response = (StackEnumerateResponse *)&packet;
for (i = 0; i < PACKET_MAX_STACK_ENUMERATE_UIDS; i++) {
if (response->uids[i] != 0) {
uid_counter++;
stack_add_recipient(&_red_stack.base, response->uids[i], stack_address);
log_debug("Found UID number %d of slave %d with UID %s",
i, stack_address,
base58_encode(base58, uint32_from_le(response->uids[i])));
} else {
break;
}
}
stack_address++;
}
_red_stack.slave_num = stack_address;
log_info("SPI stack slave discovery done. Found %d slave(s) with %d UID(s) in total",
stack_address, uid_counter);
}
int websocket_parse_header(Websocket *websocket, uint8_t *buffer, int length) {
int websocket_frame_length = sizeof(WebsocketFrame);
int to_copy = MIN(length, websocket_frame_length - websocket->frame_index);
if (to_copy <= 0) {
log_error("WebSocket frame index has invalid value (%d)", websocket->frame_index);
return -1;
}
memcpy(((char*)&websocket->frame) + websocket->frame_index, buffer, to_copy);
if (to_copy + websocket->frame_index < websocket_frame_length) {
websocket->frame_index += to_copy;
return IO_CONTINUE;
} else {
int fin = websocket_frame_get_fin(&websocket->frame.header);
int opcode = websocket_frame_get_opcode(&websocket->frame.header);
int payload_length = websocket_frame_get_payload_length(&websocket->frame.header);
int mask = websocket_frame_get_mask(&websocket->frame.header);
log_packet_debug("WebSocket header received (fin: %d, opc: %d, len: %d, key: [%d %d %d %d])",
fin, opcode, payload_length,
websocket->frame.masking_key[0],
websocket->frame.masking_key[1],
websocket->frame.masking_key[2],
websocket->frame.masking_key[3]);
if (mask != 1) {
log_error("WebSocket frame has invalid mask (%d)", mask);
return -1;
}
if (payload_length == 126 || payload_length == 127) {
log_error("WebSocket frame with extended payload length not supported (%d)", payload_length);
return -1;
}
switch (opcode) {
case WEBSOCKET_OPCODE_CONTINUATION_FRAME:
case WEBSOCKET_OPCODE_TEXT_FRAME:
log_error("WebSocket opcodes 'continuation' and 'text' not supported");
return -1;
case WEBSOCKET_OPCODE_BINARY_FRAME:
websocket->mask_index = 0;
websocket->frame_index = 0;
websocket->to_read = payload_length;
websocket->state = WEBSOCKET_STATE_HEADER_DONE;
if (length - to_copy > 0) {
memmove(buffer, buffer + to_copy, length - to_copy);
return websocket_parse_data(websocket, buffer, length - to_copy);
}
return IO_CONTINUE;
case WEBSOCKET_OPCODE_CLOSE_FRAME:
log_debug("WebSocket opcode 'close frame'");
return 0;
case WEBSOCKET_OPCODE_PING_FRAME:
log_error("WebSocket opcode 'ping' not supported");
return -1;
case WEBSOCKET_OPCODE_PONG_FRAME:
log_error("WebSocket opcode 'pong' not supported");
return -1;
}
}
log_error("Unknown WebSocket opcode (%d)", websocket_frame_get_opcode(&websocket->frame.header));
return -1;
}
