static void handle_signals(const char *req, int *req_index)
{
// No arguments
(void) req;
(void) req_index;
if (!uart_is_open(uart)) {
send_error_response("ebadf");
return;
}
struct uart_signals sig;
if (uart_get_signals(uart, &sig) >= 0) {
char resp[128];
int resp_index = sizeof(uint16_t);
resp[resp_index++] = response_id;
ei_encode_version(resp, &resp_index);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "ok");
ei_encode_map_header(resp, &resp_index, 8);
encode_kv_bool(resp, &resp_index, "dsr", sig.dsr);
encode_kv_bool(resp, &resp_index, "dtr", sig.dtr);
encode_kv_bool(resp, &resp_index, "rts", sig.rts);
encode_kv_bool(resp, &resp_index, "st", sig.st);
encode_kv_bool(resp, &resp_index, "sr", sig.sr);
encode_kv_bool(resp, &resp_index, "cts", sig.cts);
encode_kv_bool(resp, &resp_index, "cd", sig.cd);
encode_kv_bool(resp, &resp_index, "rng", sig.rng);
erlcmd_send(resp, resp_index);
} else
send_error_response(uart_last_error());
}
/**
* @brief Send :ok back to Elixir
*/
static void send_ok_response()
{
char resp[256];
int resp_index = sizeof(uint16_t); // Space for payload size
ei_encode_version(resp, &resp_index);
ei_encode_atom(resp, &resp_index, "ok");
erlcmd_send(resp, resp_index);
}
/**
* @brief Send a response of the form {:error, reason}
*
* @param reason a reason (sent back as an atom)
*/
static void send_error_response(const char *reason)
{
char resp[256];
int resp_index = sizeof(uint16_t); // Space for payload size
ei_encode_version(resp, &resp_index);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "error");
ei_encode_atom(resp, &resp_index, reason);
erlcmd_send(resp, resp_index);
}
static void enumerate_ports()
{
struct serial_info *port_list = find_serialports();
int port_list_len = 0;
for (struct serial_info *port = port_list;
port != NULL;
port = port->next)
port_list_len++;
debug("Found %d ports", port_list_len);
char resp[4096];
int resp_index = sizeof(uint16_t); // Space for payload size
resp[resp_index++] = response_id;
ei_encode_version(resp, &resp_index);
ei_encode_map_header(resp, &resp_index, port_list_len);
for (struct serial_info *port = port_list;
port != NULL;
port = port->next) {
ei_encode_binary(resp, &resp_index, port->name, strlen(port->name));
int info_count = (port->description ? 1 : 0) +
(port->manufacturer ? 1 : 0) +
(port->serial_number ? 1 : 0) +
(port->vid > 0 ? 1 : 0) +
(port->pid > 0 ? 1 : 0);
ei_encode_map_header(resp, &resp_index, info_count);
if (port->description) {
ei_encode_atom(resp, &resp_index, "description");
ei_encode_binary(resp, &resp_index, port->description, strlen(port->description));
}
if (port->manufacturer) {
ei_encode_atom(resp, &resp_index, "manufacturer");
ei_encode_binary(resp, &resp_index, port->manufacturer, strlen(port->manufacturer));
}
if (port->serial_number) {
ei_encode_atom(resp, &resp_index, "serial_number");
ei_encode_binary(resp, &resp_index, port->serial_number, strlen(port->serial_number));
}
if (port->vid > 0) {
ei_encode_atom(resp, &resp_index, "vendor_id");
ei_encode_ulong(resp, &resp_index, port->vid);
}
if (port->pid > 0) {
ei_encode_atom(resp, &resp_index, "product_id");
ei_encode_ulong(resp, &resp_index, port->pid);
}
}
erlcmd_send(resp, resp_index);
serial_info_free_list(port_list);
}
/* Called when uart_read completes or fails */
static void handle_read_completed(int rc, const uint8_t *data, size_t len)
{
if (rc >= 0) {
char *resp = malloc(32 + len);
int resp_index = sizeof(uint16_t);
ei_encode_version(resp, &resp_index);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "ok");
ei_encode_binary(resp, &resp_index, data, len);
erlcmd_send(resp, resp_index);
free(resp);
} else
send_error_response(uart_last_error());
}
static void handle_configuration(const char *req, int *req_index)
{
char resp[256];
int resp_index = sizeof(uint16_t); // Space for payload size
resp[resp_index++] = response_id;
ei_encode_version(resp, &resp_index);
ei_encode_list_header(resp, &resp_index, 5);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "speed");
ei_encode_long(resp, &resp_index, current_config.speed);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "data_bits");
ei_encode_long(resp, &resp_index, current_config.data_bits);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "stop_bits");
ei_encode_long(resp, &resp_index, current_config.stop_bits);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "parity");
switch (current_config.parity) {
default:
case UART_PARITY_NONE: ei_encode_atom(resp, &resp_index, "none"); break;
case UART_PARITY_EVEN: ei_encode_atom(resp, &resp_index, "even"); break;
case UART_PARITY_ODD: ei_encode_atom(resp, &resp_index, "odd"); break;
case UART_PARITY_SPACE: ei_encode_atom(resp, &resp_index, "space"); break;
case UART_PARITY_MARK: ei_encode_atom(resp, &resp_index, "mark"); break;
case UART_PARITY_IGNORE: ei_encode_atom(resp, &resp_index, "ignore"); break;
}
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "flow_control");
switch (current_config.parity) {
default:
case UART_FLOWCONTROL_NONE: ei_encode_atom(resp, &resp_index, "none"); break;
case UART_FLOWCONTROL_HARDWARE: ei_encode_atom(resp, &resp_index, "hardware"); break;
case UART_FLOWCONTROL_SOFTWARE: ei_encode_atom(resp, &resp_index, "software"); break;
}
ei_encode_empty_list(resp, &resp_index);
erlcmd_send(resp, resp_index);
}
/* Called in active mode when there's a read or an error */
static void handle_notify_read(int error_reason, const uint8_t *data, size_t len)
{
char *resp = malloc(64 + len);
int resp_index = sizeof(uint16_t);
ei_encode_version(resp, &resp_index);
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "notif");
if (error_reason == 0) {
// Normal receive
ei_encode_binary(resp, &resp_index, data, len);
} else {
// Error notification
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "error");
ei_encode_atom(resp, &resp_index, uart_last_error());
}
erlcmd_send(resp, resp_index);
free(resp);
}
static void i2c_handle_request(const char *req, void *cookie)
{
struct i2c_info *i2c = (struct i2c_info *) cookie;
// Commands are of the form {Command, Arguments}:
// { atom(), term() }
int req_index = sizeof(uint16_t);
if (ei_decode_version(req, &req_index, NULL) < 0)
errx(EXIT_FAILURE, "Message version issue?");
int arity;
if (ei_decode_tuple_header(req, &req_index, &arity) < 0 ||
arity != 2)
errx(EXIT_FAILURE, "expecting {cmd, args} tuple");
char cmd[MAXATOMLEN];
if (ei_decode_atom(req, &req_index, cmd) < 0)
errx(EXIT_FAILURE, "expecting command atom");
char resp[256];
int resp_index = sizeof(uint16_t); // Space for payload size
ei_encode_version(resp, &resp_index);
if (strcmp(cmd, "read") == 0) {
long int len;
if (ei_decode_long(req, &req_index, &len) < 0 ||
len < 1 ||
len > I2C_SMBUS_BLOCK_MAX)
errx(EXIT_FAILURE, "read amount: min=1, max=%d", I2C_SMBUS_BLOCK_MAX);
char data[I2C_SMBUS_BLOCK_MAX];
if (i2c_transfer(i2c, 0, 0, data, len))
ei_encode_binary(resp, &resp_index, data,len);
else {
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "error");
ei_encode_atom(resp, &resp_index, "i2c_read_failed");
}
} else if (strcmp(cmd, "write") == 0) {
char data[I2C_SMBUS_BLOCK_MAX];
int len;
int type;
long llen;
if (ei_get_type(req, &req_index, &type, &len) < 0 ||
type != ERL_BINARY_EXT ||
len < 1 ||
len > I2C_SMBUS_BLOCK_MAX ||
ei_decode_binary(req, &req_index, &data, &llen) < 0)
errx(EXIT_FAILURE, "write: need a binary between 1 and %d bytes", I2C_SMBUS_BLOCK_MAX);
if (i2c_transfer(i2c, data, len, 0, 0))
ei_encode_atom(resp, &resp_index, "ok");
else {
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "error");
ei_encode_atom(resp, &resp_index, "i2c_write_failed");
}
} else if (strcmp(cmd, "wrrd") == 0) {
char write_data[I2C_SMBUS_BLOCK_MAX];
char read_data[I2C_SMBUS_BLOCK_MAX];
int write_len;
long int read_len;
int type;
long llen;
if (ei_decode_tuple_header(req, &req_index, &arity) < 0 ||
arity != 2)
errx(EXIT_FAILURE, "wrrd: expecting {write_data, read_count} tuple");
if (ei_get_type(req, &req_index, &type, &write_len) < 0 ||
type != ERL_BINARY_EXT ||
write_len < 1 ||
write_len > I2C_SMBUS_BLOCK_MAX ||
ei_decode_binary(req, &req_index, &write_data, &llen) < 0)
errx(EXIT_FAILURE, "wrrd: need a binary between 1 and %d bytes", I2C_SMBUS_BLOCK_MAX);
if (ei_decode_long(req, &req_index, &read_len) < 0 ||
read_len < 1 ||
read_len > I2C_SMBUS_BLOCK_MAX)
errx(EXIT_FAILURE, "wrrd: read amount: min=1, max=%d", I2C_SMBUS_BLOCK_MAX);
if (i2c_transfer(i2c, write_data, write_len, read_data, read_len))
ei_encode_binary(resp, &resp_index, read_data, read_len);
else {
ei_encode_tuple_header(resp, &resp_index, 2);
ei_encode_atom(resp, &resp_index, "error");
ei_encode_atom(resp, &resp_index, "i2c_wrrd_failed");
}
} else
errx(EXIT_FAILURE, "unknown command: %s", cmd);
debug("sending response: %d bytes", resp_index);
erlcmd_send(resp, resp_index);
}