+ /* Disable canonical mode, and don't echo input characters. */
+ term.c_lflag &= ~(ICANON | ECHO);
+
+ /* Write the configured settings. */
+ if (tcsetattr(serial->fd, TCSADRAIN, &term) < 0) {
+ sr_err("tcsetattr() error: %s.", strerror(errno));
+ return SR_ERR;
+ }
+
+ if (rts != -1) {
+ sr_spew("Setting RTS %s.", rts ? "high" : "low");
+ controlbits = TIOCM_RTS;
+ if ((ret = ioctl(serial->fd, rts ? TIOCMBIS : TIOCMBIC,
+ &controlbits)) < 0) {
+ sr_err("Error setting RTS: %s.", strerror(errno));
+ return SR_ERR;
+ }
+ }
+
+ if (dtr != -1) {
+ sr_spew("Setting DTR %s.", dtr ? "high" : "low");
+ controlbits = TIOCM_DTR;
+ if ((ret = ioctl(serial->fd, dtr ? TIOCMBIS : TIOCMBIC,
+ &controlbits)) < 0) {
+ sr_err("Error setting DTR: %s.", strerror(errno));
+ return SR_ERR;
+ }
+ }
+
+#endif
+
+ return SR_OK;
+}
+
+/**
+ * Set serial parameters for the specified serial port.
+ *
+ * @param serial Previously initialized serial port structure.
+ * @param paramstr A serial communication parameters string, in the form
+ * of <speed>/<data bits><parity><stopbits><flow>, for example "9600/8n1" or
+ * "600/7o2" or "460800/8n1/flow=2" where flow is 0 for none, 1 for rts/cts and 2 for xon/xoff.
+ *
+ * @return SR_OK upon success, SR_ERR upon failure.
+ */
+#define SERIAL_COMM_SPEC "^(\\d+)/([78])([neo])([12])(.*)$"
+SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
+ const char *paramstr)
+{
+ GRegex *reg;
+ GMatchInfo *match;
+ int speed, databits, parity, stopbits, flow, rts, dtr, i;
+ char *mstr, **opts, **kv;
+
+ speed = databits = parity = stopbits = flow = 0;
+ rts = dtr = -1;
+ sr_spew("Parsing parameters from \"%s\".", paramstr);
+ reg = g_regex_new(SERIAL_COMM_SPEC, 0, 0, NULL);
+ if (g_regex_match(reg, paramstr, 0, &match)) {
+ if ((mstr = g_match_info_fetch(match, 1)))
+ speed = strtoul(mstr, NULL, 10);
+ g_free(mstr);
+ if ((mstr = g_match_info_fetch(match, 2)))
+ databits = strtoul(mstr, NULL, 10);
+ g_free(mstr);
+ if ((mstr = g_match_info_fetch(match, 3))) {
+ switch (mstr[0]) {
+ case 'n':
+ parity = SERIAL_PARITY_NONE;
+ break;
+ case 'e':
+ parity = SERIAL_PARITY_EVEN;
+ break;
+ case 'o':
+ parity = SERIAL_PARITY_ODD;
+ break;
+ }
+ }
+ g_free(mstr);
+ if ((mstr = g_match_info_fetch(match, 4)))
+ stopbits = strtoul(mstr, NULL, 10);
+ g_free(mstr);
+ if ((mstr = g_match_info_fetch(match, 5)) && mstr[0] != '\0') {
+ if (mstr[0] != '/') {
+ sr_dbg("missing separator before extra options");
+ speed = 0;
+ } else {
+ /* A set of "key=value" options separated by / */
+ opts = g_strsplit(mstr + 1, "/", 0);
+ for (i = 0; opts[i]; i++) {
+ kv = g_strsplit(opts[i], "=", 2);
+ if (!strncmp(kv[0], "rts", 3)) {
+ if (kv[1][0] == '1')
+ rts = 1;
+ else if (kv[1][0] == '0')
+ rts = 0;
+ else {
+ sr_dbg("invalid value for rts: %c", kv[1][0]);
+ speed = 0;
+ }
+ } else if (!strncmp(kv[0], "dtr", 3)) {
+ if (kv[1][0] == '1')
+ dtr = 1;
+ else if (kv[1][0] == '0')
+ dtr = 0;
+ else {
+ sr_dbg("invalid value for dtr: %c", kv[1][0]);
+ speed = 0;
+ }
+ } else if (!strncmp(kv[0], "flow", 4)) {
+ if (kv[1][0] == '0')
+ flow = 0;
+ else if (kv[1][0] == '1')
+ flow = 1;
+ else if (kv[1][0] == '2')
+ flow = 2;
+ else {
+ sr_dbg("invalid value for flow: %c", kv[1][0]);
+ speed = 0;
+ }
+ }
+ g_strfreev(kv);
+ }
+ g_strfreev(opts);
+ }
+ }
+ g_free(mstr);
+ }
+ g_match_info_unref(match);
+ g_regex_unref(reg);
+
+ if (speed) {
+ return serial_set_params(serial, speed, databits, parity,
+ stopbits, flow, rts, dtr);
+ } else {
+ sr_dbg("Could not infer speed from parameter string.");
+ return SR_ERR_ARG;
+ }
+}
+
+/**
+ * Read a line from the specified serial port.
+ *
+ * @param serial Previously initialized serial port structure.
+ * @param buf Buffer where to store the bytes that are read.
+ * @param buflen Size of the buffer.
+ * @param timeout_ms How long to wait for a line to come in.
+ *
+ * Reading stops when CR of LR is found, which is stripped from the buffer.
+ *
+ * @return SR_OK on success, SR_ERR on failure.
+ */
+SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial, char **buf,
+ int *buflen, gint64 timeout_ms)
+{
+ gint64 start;
+ int maxlen, len;
+
+ if (!serial || serial->fd == -1) {
+ sr_dbg("Invalid serial port.");
+ return SR_ERR;
+ }
+
+ if (serial->fd == -1) {
+ sr_dbg("Cannot use unopened serial port %s (fd %d).",
+ serial->port, serial->fd);
+ return -1;
+ }
+
+ timeout_ms *= 1000;
+ start = g_get_monotonic_time();
+
+ maxlen = *buflen;
+ *buflen = len = 0;
+ while(1) {
+ len = maxlen - *buflen - 1;
+ if (len < 1)
+ break;
+ len = serial_read(serial, *buf + *buflen, 1);
+ if (len > 0) {
+ *buflen += len;
+ *(*buf + *buflen) = '\0';
+ if (*buflen > 0 && (*(*buf + *buflen - 1) == '\r'
+ || *(*buf + *buflen - 1) == '\n')) {
+ /* Strip CR/LF and terminate. */
+ *(*buf + --*buflen) = '\0';
+ break;
+ }
+ }
+ if (g_get_monotonic_time() - start > timeout_ms)
+ /* Timeout */
+ break;
+ g_usleep(2000);
+ }
+ if (*buflen)
+ sr_dbg("Received %d: '%s'.", *buflen, *buf);
+
+ return SR_OK;
+}
+
+/**
+ * Try to find a valid packet in a serial data stream.
+ *
+ * @param serial Previously initialized serial port structure.
+ * @param buf Buffer containing the bytes to write.
+ * @param count Size of the buffer.
+ * @param packet_size Size, in bytes, of a valid packet.
+ * @param is_valid Callback that assesses whether the packet is valid or not.
+ * @param timeout_ms The timeout after which, if no packet is detected, to
+ * abort scanning.
+ * @param baudrate The baudrate of the serial port. This parameter is not
+ * critical, but it helps fine tune the serial port polling
+ * delay.
+ *
+ * @return SR_OK if a valid packet is found within the given timeout,
+ * SR_ERR upon failure.
+ */
+SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
+ uint8_t *buf, size_t *buflen,
+ size_t packet_size, packet_valid_t is_valid,
+ uint64_t timeout_ms, int baudrate)
+{
+ uint64_t start, time, byte_delay_us;
+ size_t ibuf, i, maxlen;
+ int len;
+
+ maxlen = *buflen;
+
+ sr_dbg("Detecting packets on FD %d (timeout = %" PRIu64
+ "ms, baudrate = %d).", serial->fd, timeout_ms, baudrate);
+
+ if (maxlen < (packet_size / 2) ) {
+ sr_err("Buffer size must be at least twice the packet size.");
+ return SR_ERR;
+ }
+
+ /* Assume 8n1 transmission. That is 10 bits for every byte. */
+ byte_delay_us = 10 * (1000000 / baudrate);
+ start = g_get_monotonic_time();
+
+ i = ibuf = len = 0;
+ while (ibuf < maxlen) {
+ len = serial_read(serial, &buf[ibuf], 1);
+ if (len > 0) {
+ ibuf += len;
+ } else if (len == 0) {
+ /* No logging, already done in serial_read(). */
+ } else {
+ /* Error reading byte, but continuing anyway. */
+ }
+
+ time = g_get_monotonic_time() - start;
+ time /= 1000;
+
+ if ((ibuf - i) >= packet_size) {
+ /* We have at least a packet's worth of data. */
+ if (is_valid(&buf[i])) {
+ sr_spew("Found valid %d-byte packet after "
+ "%" PRIu64 "ms.", (ibuf - i), time);
+ *buflen = ibuf;
+ return SR_OK;
+ } else {
+ sr_spew("Got %d bytes, but not a valid "
+ "packet.", (ibuf - i));
+ }
+ /* Not a valid packet. Continue searching. */
+ i++;
+ }
+ if (time >= timeout_ms) {
+ /* Timeout */
+ sr_dbg("Detection timed out after %dms.", time);
+ break;
+ }
+ g_usleep(byte_delay_us);
+ }
+
+ *buflen = ibuf;
+
+ sr_err("Didn't find a valid packet (read %d bytes).", *buflen);
+
+ return SR_ERR;