2 * This file is part of the libsigrok project.
4 * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
5 * Copyright (C) 2010-2012 Uwe Hermann <uwe@hermann-uwe.de>
6 * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
7 * Copyright (C) 2014 Uffe Jakobsen <uffe@uffe.org>
9 * This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation, either version 3 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
27 #include <glib/gstdio.h>
28 #include <libserialport.h>
29 #include <libsigrok/libsigrok.h>
30 #include "libsigrok-internal.h"
32 #include <windows.h> /* for HANDLE */
36 #define LOG_PREFIX "serial"
42 * Serial port handling.
46 * @defgroup grp_serial Serial port handling
48 * Serial port handling functions.
53 /* See if a (assumed opened) serial port is of any supported type. */
54 static int dev_is_supported(struct sr_serial_dev_inst *serial)
58 if (!serial->lib_funcs)
65 * Open the specified serial port.
67 * @param serial Previously initialized serial port structure.
68 * @param[in] flags Flags to use when opening the serial port. Possible flags
69 * include SERIAL_RDWR, SERIAL_RDONLY.
71 * If the serial structure contains a serialcomm string, it will be
72 * passed to serial_set_paramstr() after the port is opened.
74 * @retval SR_OK Success.
75 * @retval SR_ERR Failure.
79 SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
84 sr_dbg("Invalid serial port.");
88 sr_spew("Opening serial port '%s' (flags %d).", serial->port, flags);
90 /* Default to the libserialport transport layer. */
91 serial->lib_funcs = ser_lib_funcs_libsp;
92 if (!serial->lib_funcs)
96 * Run the transport's open routine. Setup the bitrate and the
99 if (!serial->lib_funcs->open)
101 ret = serial->lib_funcs->open(serial, flags);
105 if (serial->serialcomm)
106 return serial_set_paramstr(serial, serial->serialcomm);
112 * Close the specified serial port.
114 * @param serial Previously initialized serial port structure.
116 * @retval SR_OK Success.
117 * @retval SR_ERR Failure.
121 SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
124 sr_dbg("Invalid serial port.");
128 sr_spew("Closing serial port %s.", serial->port);
130 if (!serial->lib_funcs || !serial->lib_funcs->close)
133 return serial->lib_funcs->close(serial);
137 * Flush serial port buffers. Empty buffers, discard pending RX and TX data.
139 * @param serial Previously initialized serial port structure.
141 * @retval SR_OK Success.
142 * @retval SR_ERR Failure.
146 SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
149 sr_dbg("Invalid serial port.");
153 sr_spew("Flushing serial port %s.", serial->port);
155 if (!serial->lib_funcs || !serial->lib_funcs->flush)
158 return serial->lib_funcs->flush(serial);
162 * Drain serial port buffers. Wait for pending TX data to be sent.
164 * @param serial Previously initialized serial port structure.
166 * @retval SR_OK Success.
167 * @retval SR_ERR Failure.
171 SR_PRIV int serial_drain(struct sr_serial_dev_inst *serial)
174 sr_dbg("Invalid serial port.");
178 sr_spew("Draining serial port %s.", serial->port);
180 if (!serial->lib_funcs || !serial->lib_funcs->drain)
183 return serial->lib_funcs->drain(serial);
187 * Check for available receive data.
189 * @param[in] serial Previously opened serial port instance.
191 * @returns The number of (known) available RX data bytes.
193 * Returns 0 if no receive data is available, or if the amount of
194 * available receive data cannot get determined.
196 SR_PRIV size_t serial_has_receive_data(struct sr_serial_dev_inst *serial)
204 if (serial->lib_funcs && serial->lib_funcs->get_rx_avail)
205 lib_count = serial->lib_funcs->get_rx_avail(serial);
210 static int _serial_write(struct sr_serial_dev_inst *serial,
211 const void *buf, size_t count,
212 int nonblocking, unsigned int timeout_ms)
217 sr_dbg("Invalid serial port.");
221 if (!serial->lib_funcs || !serial->lib_funcs->write)
223 ret = serial->lib_funcs->write(serial, buf, count,
224 nonblocking, timeout_ms);
225 sr_spew("Wrote %zd/%zu bytes.", ret, count);
231 * Write a number of bytes to the specified serial port, blocking until finished.
233 * @param serial Previously initialized serial port structure.
234 * @param[in] buf Buffer containing the bytes to write.
235 * @param[in] count Number of bytes to write.
236 * @param[in] timeout_ms Timeout in ms, or 0 for no timeout.
238 * @retval SR_ERR_ARG Invalid argument.
239 * @retval SR_ERR Other error.
240 * @retval other The number of bytes written. If this is less than the number
241 * specified in the call, the timeout was reached.
245 SR_PRIV int serial_write_blocking(struct sr_serial_dev_inst *serial,
246 const void *buf, size_t count, unsigned int timeout_ms)
248 return _serial_write(serial, buf, count, 0, timeout_ms);
252 * Write a number of bytes to the specified serial port, return immediately.
254 * @param serial Previously initialized serial port structure.
255 * @param[in] buf Buffer containing the bytes to write.
256 * @param[in] count Number of bytes to write.
258 * @retval SR_ERR_ARG Invalid argument.
259 * @retval SR_ERR Other error.
260 * @retval other The number of bytes written.
264 SR_PRIV int serial_write_nonblocking(struct sr_serial_dev_inst *serial,
265 const void *buf, size_t count)
267 return _serial_write(serial, buf, count, 1, 0);
270 static int _serial_read(struct sr_serial_dev_inst *serial,
271 void *buf, size_t count, int nonblocking, unsigned int timeout_ms)
276 sr_dbg("Invalid serial port.");
280 if (!serial->lib_funcs || !serial->lib_funcs->read)
282 ret = serial->lib_funcs->read(serial, buf, count,
283 nonblocking, timeout_ms);
285 sr_spew("Read %zd/%zu bytes.", ret, count);
291 * Read a number of bytes from the specified serial port, block until finished.
293 * @param serial Previously initialized serial port structure.
294 * @param buf Buffer where to store the bytes that are read.
295 * @param[in] count The number of bytes to read.
296 * @param[in] timeout_ms Timeout in ms, or 0 for no timeout.
298 * @retval SR_ERR_ARG Invalid argument.
299 * @retval SR_ERR Other error.
300 * @retval other The number of bytes read. If this is less than the number
301 * requested, the timeout was reached.
305 SR_PRIV int serial_read_blocking(struct sr_serial_dev_inst *serial,
306 void *buf, size_t count, unsigned int timeout_ms)
308 return _serial_read(serial, buf, count, 0, timeout_ms);
312 * Try to read up to @a count bytes from the specified serial port, return
313 * immediately with what's available.
315 * @param serial Previously initialized serial port structure.
316 * @param buf Buffer where to store the bytes that are read.
317 * @param[in] count The number of bytes to read.
319 * @retval SR_ERR_ARG Invalid argument.
320 * @retval SR_ERR Other error.
321 * @retval other The number of bytes read.
325 SR_PRIV int serial_read_nonblocking(struct sr_serial_dev_inst *serial,
326 void *buf, size_t count)
328 return _serial_read(serial, buf, count, 1, 0);
332 * Set serial parameters for the specified serial port.
334 * @param serial Previously initialized serial port structure.
335 * @param[in] baudrate The baudrate to set.
336 * @param[in] bits The number of data bits to use (5, 6, 7 or 8).
337 * @param[in] parity The parity setting to use (0 = none, 1 = even, 2 = odd).
338 * @param[in] stopbits The number of stop bits to use (1 or 2).
339 * @param[in] flowcontrol The flow control settings to use (0 = none,
340 * 1 = RTS/CTS, 2 = XON/XOFF).
341 * @param[in] rts Status of RTS line (0 or 1; required by some interfaces).
342 * @param[in] dtr Status of DTR line (0 or 1; required by some interfaces).
344 * @retval SR_OK Success.
345 * @retval SR_ERR Failure.
349 SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial,
350 int baudrate, int bits, int parity, int stopbits,
351 int flowcontrol, int rts, int dtr)
356 sr_dbg("Invalid serial port.");
360 sr_spew("Setting serial parameters on port %s.", serial->port);
362 if (!serial->lib_funcs || !serial->lib_funcs->set_params)
364 ret = serial->lib_funcs->set_params(serial,
365 baudrate, bits, parity, stopbits,
366 flowcontrol, rts, dtr);
368 serial->comm_params.bit_rate = baudrate;
369 serial->comm_params.data_bits = bits;
370 serial->comm_params.parity_bits = parity ? 1 : 0;
371 serial->comm_params.stop_bits = stopbits;
372 sr_dbg("DBG: %s() rate %d, %d%s%d", __func__,
374 (parity == 0) ? "n" : "x",
382 * Set serial parameters for the specified serial port from parameter string.
384 * @param serial Previously initialized serial port structure.
385 * @param[in] paramstr A serial communication parameters string of the form
386 * "<baudrate>/<bits><parity><stopbits>{/<option>}".\n
387 * Examples: "9600/8n1", "600/7o2/dtr=1/rts=0" or "460800/8n1/flow=2".\n
388 * \<baudrate\>=integer Baud rate.\n
389 * \<bits\>=5|6|7|8 Number of data bits.\n
390 * \<parity\>=n|e|o None, even, odd.\n
391 * \<stopbits\>=1|2 One or two stop bits.\n
393 * dtr=0|1 Set DTR off resp. on.\n
394 * flow=0|1|2 Flow control. 0 for none, 1 for RTS/CTS, 2 for XON/XOFF.\n
395 * rts=0|1 Set RTS off resp. on.\n
396 * Please note that values and combinations of these parameters must be
397 * supported by the concrete serial interface hardware and the drivers for it.
399 * @retval SR_OK Success.
400 * @retval SR_ERR Failure.
404 SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
405 const char *paramstr)
408 #define SERIAL_COMM_SPEC "^(\\d+)/([5678])([neo])([12])(.*)$"
413 int speed, databits, parity, stopbits, flow, rts, dtr, i;
414 char *mstr, **opts, **kv;
416 speed = databits = parity = stopbits = flow = 0;
418 sr_spew("Parsing parameters from \"%s\".", paramstr);
419 reg = g_regex_new(SERIAL_COMM_SPEC, 0, 0, NULL);
420 if (g_regex_match(reg, paramstr, 0, &match)) {
421 if ((mstr = g_match_info_fetch(match, 1)))
422 speed = strtoul(mstr, NULL, 10);
424 if ((mstr = g_match_info_fetch(match, 2)))
425 databits = strtoul(mstr, NULL, 10);
427 if ((mstr = g_match_info_fetch(match, 3))) {
430 parity = SP_PARITY_NONE;
433 parity = SP_PARITY_EVEN;
436 parity = SP_PARITY_ODD;
441 if ((mstr = g_match_info_fetch(match, 4)))
442 stopbits = strtoul(mstr, NULL, 10);
444 if ((mstr = g_match_info_fetch(match, 5)) && mstr[0] != '\0') {
445 if (mstr[0] != '/') {
446 sr_dbg("missing separator before extra options");
449 /* A set of "key=value" options separated by / */
450 opts = g_strsplit(mstr + 1, "/", 0);
451 for (i = 0; opts[i]; i++) {
452 kv = g_strsplit(opts[i], "=", 2);
453 if (!strncmp(kv[0], "rts", 3)) {
456 else if (kv[1][0] == '0')
459 sr_dbg("invalid value for rts: %c", kv[1][0]);
462 } else if (!strncmp(kv[0], "dtr", 3)) {
465 else if (kv[1][0] == '0')
468 sr_dbg("invalid value for dtr: %c", kv[1][0]);
471 } else if (!strncmp(kv[0], "flow", 4)) {
474 else if (kv[1][0] == '1')
476 else if (kv[1][0] == '2')
479 sr_dbg("invalid value for flow: %c", kv[1][0]);
490 g_match_info_unref(match);
494 return serial_set_params(serial, speed, databits, parity,
495 stopbits, flow, rts, dtr);
497 sr_dbg("Could not infer speed from parameter string.");
503 * Read a line from the specified serial port.
505 * @param[in] serial Previously initialized serial port structure.
506 * @param[out] buf Buffer where to store the bytes that are read.
507 * @param[in] buflen Size of the buffer.
508 * @param[in] timeout_ms How long to wait for a line to come in.
510 * Reading stops when CR or LF is found, which is stripped from the buffer.
512 * @retval SR_OK Success.
513 * @retval SR_ERR Failure.
517 SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial,
518 char **buf, int *buflen, gint64 timeout_ms)
520 gint64 start, remaining;
524 sr_dbg("Invalid serial port.");
528 if (!dev_is_supported(serial)) {
529 sr_dbg("Cannot use unopened serial port %s.", serial->port);
533 start = g_get_monotonic_time();
534 remaining = timeout_ms;
539 len = maxlen - *buflen - 1;
542 len = serial_read_blocking(serial, *buf + *buflen, 1, remaining);
545 *(*buf + *buflen) = '\0';
546 if (*buflen > 0 && (*(*buf + *buflen - 1) == '\r'
547 || *(*buf + *buflen - 1) == '\n')) {
548 /* Strip CR/LF and terminate. */
549 *(*buf + --*buflen) = '\0';
553 /* Reduce timeout by time elapsed. */
554 remaining = timeout_ms - ((g_get_monotonic_time() - start) / 1000);
562 sr_dbg("Received %d: '%s'.", *buflen, *buf);
568 * Try to find a valid packet in a serial data stream.
570 * @param serial Previously initialized serial port structure.
571 * @param buf Buffer containing the bytes to write.
572 * @param buflen Size of the buffer.
573 * @param[in] packet_size Size, in bytes, of a valid packet.
574 * @param is_valid Callback that assesses whether the packet is valid or not.
575 * @param[in] timeout_ms The timeout after which, if no packet is detected, to
577 * @param[in] baudrate The baudrate of the serial port. This parameter is not
578 * critical, but it helps fine tune the serial port polling
581 * @retval SR_OK Valid packet was found within the given timeout.
582 * @retval SR_ERR Failure.
586 SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
587 uint8_t *buf, size_t *buflen,
589 packet_valid_callback is_valid,
590 uint64_t timeout_ms, int baudrate)
592 uint64_t start, time, byte_delay_us;
593 size_t ibuf, i, maxlen;
598 sr_dbg("Detecting packets on %s (timeout = %" PRIu64
599 "ms, baudrate = %d).", serial->port, timeout_ms, baudrate);
601 if (maxlen < (packet_size / 2) ) {
602 sr_err("Buffer size must be at least twice the packet size.");
606 /* Assume 8n1 transmission. That is 10 bits for every byte. */
607 byte_delay_us = 10 * ((1000 * 1000) / baudrate);
608 start = g_get_monotonic_time();
611 while (ibuf < maxlen) {
612 len = serial_read_nonblocking(serial, &buf[ibuf], 1);
615 } else if (len == 0) {
616 /* No logging, already done in serial_read(). */
618 /* Error reading byte, but continuing anyway. */
621 time = g_get_monotonic_time() - start;
624 if ((ibuf - i) >= packet_size) {
626 /* We have at least a packet's worth of data. */
627 text = sr_hexdump_new(&buf[i], packet_size);
628 sr_spew("Trying packet: %s", text->str);
629 sr_hexdump_free(text);
630 if (is_valid(&buf[i])) {
631 sr_spew("Found valid %zu-byte packet after "
632 "%" PRIu64 "ms.", (ibuf - i), time);
636 sr_spew("Got %zu bytes, but not a valid "
637 "packet.", (ibuf - i));
639 /* Not a valid packet. Continue searching. */
642 if (time >= timeout_ms) {
644 sr_dbg("Detection timed out after %" PRIu64 "ms.", time);
648 g_usleep(byte_delay_us);
653 sr_err("Didn't find a valid packet (read %zu bytes).", *buflen);
659 * Extract the serial device and options from the options linked list.
661 * @param options List of options passed from the command line.
662 * @param serial_device Pointer where to store the extracted serial device.
663 * @param serial_options Pointer where to store the optional extracted serial
666 * @return SR_OK if a serial_device is found, SR_ERR if no device is found. The
667 * returned string should not be freed by the caller.
671 SR_PRIV int sr_serial_extract_options(GSList *options,
672 const char **serial_device, const char **serial_options)
675 struct sr_config *src;
677 *serial_device = NULL;
679 for (l = options; l; l = l->next) {
683 *serial_device = g_variant_get_string(src->data, NULL);
684 sr_dbg("Parsed serial device: %s.", *serial_device);
686 case SR_CONF_SERIALCOMM:
687 *serial_options = g_variant_get_string(src->data, NULL);
688 sr_dbg("Parsed serial options: %s.", *serial_options);
693 if (!*serial_device) {
694 sr_dbg("No serial device specified.");
702 SR_PRIV int serial_source_add(struct sr_session *session,
703 struct sr_serial_dev_inst *serial, int events, int timeout,
704 sr_receive_data_callback cb, void *cb_data)
706 if ((events & (G_IO_IN | G_IO_ERR)) && (events & G_IO_OUT)) {
707 sr_err("Cannot poll input/error and output simultaneously.");
711 if (!dev_is_supported(serial)) {
712 sr_err("Invalid serial port.");
716 if (!serial->lib_funcs || !serial->lib_funcs->setup_source_add)
719 return serial->lib_funcs->setup_source_add(session, serial,
720 events, timeout, cb, cb_data);
724 SR_PRIV int serial_source_remove(struct sr_session *session,
725 struct sr_serial_dev_inst *serial)
727 if (!dev_is_supported(serial)) {
728 sr_err("Invalid serial port.");
732 if (!serial->lib_funcs || !serial->lib_funcs->setup_source_remove)
735 return serial->lib_funcs->setup_source_remove(session, serial);
739 * Create/allocate a new sr_serial_port structure.
741 * @param name The OS dependent name of the serial port. Must not be NULL.
742 * @param description An end user friendly description for the serial port.
743 * Can be NULL (in that case the empty string is used
746 * @return The newly allocated sr_serial_port struct.
748 static struct sr_serial_port *sr_serial_new(const char *name,
749 const char *description)
751 struct sr_serial_port *serial;
756 serial = g_malloc0(sizeof(*serial));
757 serial->name = g_strdup(name);
758 serial->description = g_strdup(description ? description : "");
764 * Free a previously allocated sr_serial_port structure.
766 * @param serial The sr_serial_port struct to free. Must not be NULL.
768 SR_API void sr_serial_free(struct sr_serial_port *serial)
772 g_free(serial->name);
773 g_free(serial->description);
777 static GSList *append_port_list(GSList *devs, const char *name, const char *desc)
779 return g_slist_append(devs, sr_serial_new(name, desc));
783 * List available serial devices.
785 * @return A GSList of strings containing the path of the serial devices or
786 * NULL if no serial device is found. The returned list must be freed
789 SR_API GSList *sr_serial_list(const struct sr_dev_driver *driver)
792 GSList *(*list_func)(GSList *list, sr_ser_list_append_t append);
794 /* Currently unused, but will be used by some drivers later on. */
798 if (ser_lib_funcs_libsp && ser_lib_funcs_libsp->list) {
799 list_func = ser_lib_funcs_libsp->list;
800 tty_devs = list_func(tty_devs, append_port_list);
806 static GSList *append_port_find(GSList *devs, const char *name)
811 return g_slist_append(devs, g_strdup(name));
815 * Find USB serial devices via the USB vendor ID and product ID.
817 * @param[in] vendor_id Vendor ID of the USB device.
818 * @param[in] product_id Product ID of the USB device.
820 * @return A GSList of strings containing the path of the serial device or
821 * NULL if no serial device is found. The returned list must be freed
826 SR_PRIV GSList *sr_serial_find_usb(uint16_t vendor_id, uint16_t product_id)
829 GSList *(*find_func)(GSList *list, sr_ser_find_append_t append,
830 uint16_t vid, uint16_t pid);
833 if (ser_lib_funcs_libsp && ser_lib_funcs_libsp->find_usb) {
834 find_func = ser_lib_funcs_libsp->find_usb;
835 tty_devs = find_func(tty_devs, append_port_find,
836 vendor_id, product_id);
843 SR_PRIV int serial_timeout(struct sr_serial_dev_inst *port, int num_bytes)
849 /* Get the bitrate and frame length. */
851 if (port->lib_funcs && port->lib_funcs->get_frame_format) {
852 ret = port->lib_funcs->get_frame_format(port, &baud, &bits);
856 baud = port->comm_params.bit_rate;
857 bits = 1 + port->comm_params.data_bits +
858 port->comm_params.parity_bits +
859 port->comm_params.stop_bits;
862 /* Derive the timeout. Default to 1s. */
865 /* Throw in 10ms for misc OS overhead. */
867 timeout_ms += ((1000.0 / baud) * bits) * num_bytes;