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>
8 * This program is free software: you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation, either version 3 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program. If not, see <http://www.gnu.org/licenses/>.
25 #include <libserialport.h>
26 #include "libsigrok.h"
27 #include "libsigrok-internal.h"
29 /* Message logging helpers with subsystem-specific prefix string. */
30 #define LOG_PREFIX "serial: "
31 #define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
32 #define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
33 #define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
34 #define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
35 #define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
36 #define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)
39 * Open the specified serial port.
41 * @param serial Previously initialized serial port structure.
42 * @param flags Flags to use when opening the serial port. Possible flags
43 * include SERIAL_RDWR, SERIAL_RDONLY, SERIAL_NONBLOCK.
45 * If the serial structure contains a serialcomm string, it will be
46 * passed to serial_set_paramstr() after the port is opened.
48 * @return SR_OK on success, SR_ERR on failure.
50 SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
56 sr_dbg("Invalid serial port.");
60 sr_spew("Opening serial port '%s' (flags %d).", serial->port, flags);
62 sp_get_port_by_name(serial->port, &serial->data);
64 ret = sp_open(serial->data, flags);
68 sr_err("Attempt to open serial port with invalid parameters.");
71 error = sp_last_error_message();
72 sr_err("Error opening port: %s.", error);
73 sp_free_error_message(error);
78 serial->fd = serial->data->fd;
81 if (serial->serialcomm)
82 return serial_set_paramstr(serial, serial->serialcomm);
88 * Close the specified serial port.
90 * @param serial Previously initialized serial port structure.
92 * @return SR_OK on success, SR_ERR on failure.
94 SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
100 sr_dbg("Invalid serial port.");
104 if (serial->fd == -1) {
105 sr_dbg("Cannot close unopened serial port %s (fd %d).",
106 serial->port, serial->fd);
110 sr_spew("Closing serial port %s (fd %d).", serial->port, serial->fd);
112 ret = sp_close(serial->data);
113 sp_free_port(serial->data);
117 sr_err("Attempt to close an invalid serial port.");
120 error = sp_last_error_message();
121 sr_err("Error closing port: %s.", error);
122 sp_free_error_message(error);
132 * Flush serial port buffers.
134 * @param serial Previously initialized serial port structure.
136 * @return SR_OK on success, SR_ERR on failure.
138 SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
144 sr_dbg("Invalid serial port.");
148 if (serial->fd == -1) {
149 sr_dbg("Cannot flush unopened serial port %s (fd %d).",
150 serial->port, serial->fd);
154 sr_spew("Flushing serial port %s (fd %d).", serial->port, serial->fd);
156 ret = sp_flush(serial->data);
160 sr_err("Attempt to flush an invalid serial port.");
163 error = sp_last_error_message();
164 sr_err("Error flushing port: %s.", error);
165 sp_free_error_message(error);
173 * Write a number of bytes to the specified serial port.
175 * @param serial Previously initialized serial port structure.
176 * @param buf Buffer containing the bytes to write.
177 * @param count Number of bytes to write.
179 * @return The number of bytes written, or a negative error code upon failure.
181 SR_PRIV int serial_write(struct sr_serial_dev_inst *serial,
182 const void *buf, size_t count)
188 sr_dbg("Invalid serial port.");
192 if (serial->fd == -1) {
193 sr_dbg("Cannot use unopened serial port %s (fd %d).",
194 serial->port, serial->fd);
198 ret = sp_write(serial->data, buf, count);
202 sr_err("Attempted serial port write with invalid arguments.");
205 error = sp_last_error_message();
206 sr_err("Write error: %s.", error);
207 sp_free_error_message(error);
211 sr_spew("Wrote %d/%d bytes (fd %d).", ret, count, serial->fd);
217 * Read a number of bytes from the specified serial port.
219 * @param serial Previously initialized serial port structure.
220 * @param buf Buffer where to store the bytes that are read.
221 * @param count The number of bytes to read.
223 * @return The number of bytes read, or a negative error code upon failure.
225 SR_PRIV int serial_read(struct sr_serial_dev_inst *serial, void *buf,
232 sr_dbg("Invalid serial port.");
236 if (serial->fd == -1) {
237 sr_dbg("Cannot use unopened serial port %s (fd %d).",
238 serial->port, serial->fd);
242 ret = sp_read(serial->data, buf, count);
246 sr_err("Attempted serial port read with invalid arguments.");
248 // Temporarily disabled, will come back later.
250 // error = sp_last_error_message();
251 // sr_err("Read error: %s.", error);
252 // sp_free_error_message(error);
257 sr_spew("Read %d/%d bytes (fd %d).", ret, count, serial->fd);
263 * Set serial parameters for the specified serial port.
265 * @param serial Previously initialized serial port structure.
266 * @param baudrate The baudrate to set.
267 * @param bits The number of data bits to use.
268 * @param parity The parity setting to use (0 = none, 1 = even, 2 = odd).
269 * @param stopbits The number of stop bits to use (1 or 2).
270 * @param flowcontrol The flow control settings to use (0 = none, 1 = RTS/CTS,
273 * @return SR_OK upon success, SR_ERR upon failure.
275 SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
276 int bits, int parity, int stopbits,
277 int flowcontrol, int rts, int dtr)
281 struct sp_port_config config;
284 sr_dbg("Invalid serial port.");
288 if (serial->fd == -1) {
289 sr_dbg("Cannot configure unopened serial port %s (fd %d).",
290 serial->port, serial->fd);
294 sr_spew("Setting serial parameters on port %s (fd %d).", serial->port,
297 config.baudrate = baudrate;
299 config.parity = parity;
300 config.stopbits = stopbits;
301 config.rts = flowcontrol == 1 ? SP_RTS_FLOW_CONTROL : rts;
302 config.cts = flowcontrol == 1 ? SP_CTS_FLOW_CONTROL : SP_CTS_IGNORE;
304 config.dsr = SP_DSR_IGNORE;
305 config.xon_xoff = flowcontrol == 2 ? SP_XONXOFF_INOUT : SP_XONXOFF_DISABLED;
307 ret = sp_set_config(serial->data, &config);
311 sr_err("Invalid arguments for setting serial port parameters.");
314 error = sp_last_error_message();
315 sr_err("Error setting serial port parameters: %s.", error);
316 sp_free_error_message(error);
324 * Set serial parameters for the specified serial port.
326 * @param serial Previously initialized serial port structure.
327 * @param paramstr A serial communication parameters string, in the form
328 * of <speed>/<data bits><parity><stopbits><flow>, for example "9600/8n1" or
329 * "600/7o2" or "460800/8n1/flow=2" where flow is 0 for none, 1 for rts/cts and 2 for xon/xoff.
331 * @return SR_OK upon success, SR_ERR upon failure.
333 #define SERIAL_COMM_SPEC "^(\\d+)/([78])([neo])([12])(.*)$"
334 SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
335 const char *paramstr)
339 int speed, databits, parity, stopbits, flow, rts, dtr, i;
340 char *mstr, **opts, **kv;
342 speed = databits = parity = stopbits = flow = 0;
344 sr_spew("Parsing parameters from \"%s\".", paramstr);
345 reg = g_regex_new(SERIAL_COMM_SPEC, 0, 0, NULL);
346 if (g_regex_match(reg, paramstr, 0, &match)) {
347 if ((mstr = g_match_info_fetch(match, 1)))
348 speed = strtoul(mstr, NULL, 10);
350 if ((mstr = g_match_info_fetch(match, 2)))
351 databits = strtoul(mstr, NULL, 10);
353 if ((mstr = g_match_info_fetch(match, 3))) {
356 parity = SERIAL_PARITY_NONE;
359 parity = SERIAL_PARITY_EVEN;
362 parity = SERIAL_PARITY_ODD;
367 if ((mstr = g_match_info_fetch(match, 4)))
368 stopbits = strtoul(mstr, NULL, 10);
370 if ((mstr = g_match_info_fetch(match, 5)) && mstr[0] != '\0') {
371 if (mstr[0] != '/') {
372 sr_dbg("missing separator before extra options");
375 /* A set of "key=value" options separated by / */
376 opts = g_strsplit(mstr + 1, "/", 0);
377 for (i = 0; opts[i]; i++) {
378 kv = g_strsplit(opts[i], "=", 2);
379 if (!strncmp(kv[0], "rts", 3)) {
382 else if (kv[1][0] == '0')
385 sr_dbg("invalid value for rts: %c", kv[1][0]);
388 } else if (!strncmp(kv[0], "dtr", 3)) {
391 else if (kv[1][0] == '0')
394 sr_dbg("invalid value for dtr: %c", kv[1][0]);
397 } else if (!strncmp(kv[0], "flow", 4)) {
400 else if (kv[1][0] == '1')
402 else if (kv[1][0] == '2')
405 sr_dbg("invalid value for flow: %c", kv[1][0]);
416 g_match_info_unref(match);
420 return serial_set_params(serial, speed, databits, parity,
421 stopbits, flow, rts, dtr);
423 sr_dbg("Could not infer speed from parameter string.");
429 * Read a line from the specified serial port.
431 * @param serial Previously initialized serial port structure.
432 * @param buf Buffer where to store the bytes that are read.
433 * @param buflen Size of the buffer.
434 * @param timeout_ms How long to wait for a line to come in.
436 * Reading stops when CR of LR is found, which is stripped from the buffer.
438 * @return SR_OK on success, SR_ERR on failure.
440 SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial, char **buf,
441 int *buflen, gint64 timeout_ms)
446 if (!serial || serial->fd == -1) {
447 sr_dbg("Invalid serial port.");
451 if (serial->fd == -1) {
452 sr_dbg("Cannot use unopened serial port %s (fd %d).",
453 serial->port, serial->fd);
458 start = g_get_monotonic_time();
463 len = maxlen - *buflen - 1;
466 len = serial_read(serial, *buf + *buflen, 1);
469 *(*buf + *buflen) = '\0';
470 if (*buflen > 0 && (*(*buf + *buflen - 1) == '\r'
471 || *(*buf + *buflen - 1) == '\n')) {
472 /* Strip CR/LF and terminate. */
473 *(*buf + --*buflen) = '\0';
477 if (g_get_monotonic_time() - start > timeout_ms)
484 sr_dbg("Received %d: '%s'.", *buflen, *buf);
490 * Try to find a valid packet in a serial data stream.
492 * @param serial Previously initialized serial port structure.
493 * @param buf Buffer containing the bytes to write.
494 * @param count Size of the buffer.
495 * @param packet_size Size, in bytes, of a valid packet.
496 * @param is_valid Callback that assesses whether the packet is valid or not.
497 * @param timeout_ms The timeout after which, if no packet is detected, to
499 * @param baudrate The baudrate of the serial port. This parameter is not
500 * critical, but it helps fine tune the serial port polling
503 * @return SR_OK if a valid packet is found within the given timeout,
504 * SR_ERR upon failure.
506 SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
507 uint8_t *buf, size_t *buflen,
508 size_t packet_size, packet_valid_t is_valid,
509 uint64_t timeout_ms, int baudrate)
511 uint64_t start, time, byte_delay_us;
512 size_t ibuf, i, maxlen;
517 sr_dbg("Detecting packets on FD %d (timeout = %" PRIu64
518 "ms, baudrate = %d).", serial->fd, timeout_ms, baudrate);
520 if (maxlen < (packet_size / 2) ) {
521 sr_err("Buffer size must be at least twice the packet size.");
525 /* Assume 8n1 transmission. That is 10 bits for every byte. */
526 byte_delay_us = 10 * (1000000 / baudrate);
527 start = g_get_monotonic_time();
530 while (ibuf < maxlen) {
531 len = serial_read(serial, &buf[ibuf], 1);
534 } else if (len == 0) {
535 /* No logging, already done in serial_read(). */
537 /* Error reading byte, but continuing anyway. */
540 time = g_get_monotonic_time() - start;
543 if ((ibuf - i) >= packet_size) {
544 /* We have at least a packet's worth of data. */
545 if (is_valid(&buf[i])) {
546 sr_spew("Found valid %d-byte packet after "
547 "%" PRIu64 "ms.", (ibuf - i), time);
551 sr_spew("Got %d bytes, but not a valid "
552 "packet.", (ibuf - i));
554 /* Not a valid packet. Continue searching. */
557 if (time >= timeout_ms) {
559 sr_dbg("Detection timed out after %dms.", time);
563 g_usleep(byte_delay_us);
568 sr_err("Didn't find a valid packet (read %d bytes).", *buflen);