[libsigrok.git] / hardware / common / serial.c

/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
 * Copyright (C) 2010-2012 Uwe Hermann <uwe@hermann-uwe.de>
 * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <string.h>
#include <stdlib.h>
#include <glib.h>
#include <serialport.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"

/* Message logging helpers with subsystem-specific prefix string. */
#define LOG_PREFIX "serial: "
#define sr_log(l, s, args...) sr_log(l, LOG_PREFIX s, ## args)
#define sr_spew(s, args...) sr_spew(LOG_PREFIX s, ## args)
#define sr_dbg(s, args...) sr_dbg(LOG_PREFIX s, ## args)
#define sr_info(s, args...) sr_info(LOG_PREFIX s, ## args)
#define sr_warn(s, args...) sr_warn(LOG_PREFIX s, ## args)
#define sr_err(s, args...) sr_err(LOG_PREFIX s, ## args)

/**
 * Open the specified serial port.
 *
 * @param serial Previously initialized serial port structure.
 * @param flags Flags to use when opening the serial port. Possible flags
 *              include SERIAL_RDWR, SERIAL_RDONLY, SERIAL_NONBLOCK.
 *
 * If the serial structure contains a serialcomm string, it will be
 * passed to serial_set_paramstr() after the port is opened.
 *
 * @return SR_OK on success, SR_ERR on failure.
 */
SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
{
	int ret;
	char *error;

	if (!serial) {
		sr_dbg("Invalid serial port.");
		return SR_ERR;
	}

	sr_spew("Opening serial port '%s' (flags %d).", serial->port, flags);

	ret = sp_open(&serial->data, serial->port, flags);

	switch (ret)
	{
		case SP_ERR_ARG:
			sr_err("Attempt to open serial port with invalid parameters.");
			return SR_ERR_ARG;
		case SP_ERR_FAIL:
			error = sp_last_error_message();
			sr_err("Error opening port: %s.", error);
			sp_free_error_message(error);
			return SR_ERR;
	}

#ifndef _WIN32
	serial->fd = serial->data.fd;
#endif

	if (serial->serialcomm)
		return serial_set_paramstr(serial, serial->serialcomm);
	else
		return SR_OK;
}

/**
 * Close the specified serial port.
 *
 * @param serial Previously initialized serial port structure.
 *
 * @return SR_OK on success, SR_ERR on failure.
 */
SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
{
	int ret;
	char *error;

	if (!serial) {
		sr_dbg("Invalid serial port.");
		return SR_ERR;
	}

	if (serial->fd == -1) {
		sr_dbg("Cannot close unopened serial port %s (fd %d).",
				serial->port, serial->fd);
		return SR_ERR;
	}

	sr_spew("Closing serial port %s (fd %d).", serial->port, serial->fd);
	ret = SR_OK;

	ret = sp_close(&serial->data);

	switch (ret)
	{
		case SP_ERR_ARG:
			sr_err("Attempt to close an invalid serial port.");
			return SR_ERR_ARG;
		case SP_ERR_FAIL:
			error = sp_last_error_message();
			sr_err("Error closing port: %s.", error);
			sp_free_error_message(error);
			return SR_ERR;
	}

	serial->fd = -1;

	return ret;
}

/**
 * Flush serial port buffers.
 *
 * @param serial Previously initialized serial port structure.
 *
 * @return SR_OK on success, SR_ERR on failure.
 */
SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
{
	int ret;
	char *error;

	if (!serial) {
		sr_dbg("Invalid serial port.");
		return SR_ERR;
	}

	if (serial->fd == -1) {
		sr_dbg("Cannot flush unopened serial port %s (fd %d).",
				serial->port, serial->fd);
		return SR_ERR;
	}

	sr_spew("Flushing serial port %s (fd %d).", serial->port, serial->fd);

	ret = sp_flush(&serial->data);

	switch (ret)
	{
		case SP_ERR_ARG:
			sr_err("Attempt to flush an invalid serial port.");
			return SR_ERR_ARG;
		case SP_ERR_FAIL:
			error = sp_last_error_message();
			sr_err("Error flushing port: %s.", error);
			sp_free_error_message(error);
			return SR_ERR;
	}

	return ret;
}

/**
 * Write a number of bytes to the specified serial port.
 *
 * @param serial Previously initialized serial port structure.
 * @param buf Buffer containing the bytes to write.
 * @param count Number of bytes to write.
 *
 * @return The number of bytes written, or -1 upon failure.
 */
SR_PRIV int serial_write(struct sr_serial_dev_inst *serial,
		const void *buf, size_t count)
{
	ssize_t ret;
	char *error;

	if (!serial) {
		sr_dbg("Invalid serial port.");
		return -1;
	}

	if (serial->fd == -1) {
		sr_dbg("Cannot use unopened serial port %s (fd %d).",
				serial->port, serial->fd);
		return -1;
	}

	ret = sp_write(&serial->data, buf, count);

	switch (ret)
	{
		case SP_ERR_ARG:
			sr_err("Attempted serial port write with invalid arguments.");
			return SR_ERR_ARG;
		case SP_ERR_FAIL:
			error = sp_last_error_message();
			sr_err("Write error: %s.", error);
			sp_free_error_message(error);
			return SR_ERR;
	}

	sr_spew("Wrote %d/%d bytes (fd %d).", ret, count, serial->fd);

	return ret;
}

/**
 * Read a number of bytes from the specified serial port.
 *
 * @param serial Previously initialized serial port structure.
 * @param buf Buffer where to store the bytes that are read.
 * @param count The number of bytes to read.
 *
 * @return The number of bytes read, or -1 upon failure.
 */
SR_PRIV int serial_read(struct sr_serial_dev_inst *serial, void *buf,
		size_t count)
{
	ssize_t ret;
	char *error;

	if (!serial) {
		sr_dbg("Invalid serial port.");
		return -1;
	}

	if (serial->fd == -1) {
		sr_dbg("Cannot use unopened serial port %s (fd %d).",
				serial->port, serial->fd);
		return -1;
	}

	ret = sp_read(&serial->data, buf, count);

	switch (ret)
	{
		case SP_ERR_ARG:
			sr_err("Attempted serial port read with invalid arguments.");
			return SR_ERR_ARG;
		case SP_ERR_FAIL:
			error = sp_last_error_message();
			sr_err("Read error: %s.", error);
			sp_free_error_message(error);
			return SR_ERR;
	}

	sr_spew("Read %d/%d bytes (fd %d).", ret, count, serial->fd);

	return ret;
}

/**
 * Set serial parameters for the specified serial port.
 *
 * @param serial Previously initialized serial port structure.
 * @param baudrate The baudrate to set.
 * @param bits The number of data bits to use.
 * @param parity The parity setting to use (0 = none, 1 = even, 2 = odd).
 * @param stopbits The number of stop bits to use (1 or 2).
 * @param flowcontrol The flow control settings to use (0 = none, 1 = RTS/CTS,
 *                    2 = XON/XOFF).
 *
 * @return SR_OK upon success, SR_ERR upon failure.
 */
SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
			      int bits, int parity, int stopbits,
			      int flowcontrol, int rts, int dtr)
{
	int ret;
	char *error;

	if (!serial) {
		sr_dbg("Invalid serial port.");
		return SR_ERR;
	}

	if (serial->fd == -1) {
		sr_dbg("Cannot configure unopened serial port %s (fd %d).",
		       serial->port, serial->fd);
		return SR_ERR;
	}

	sr_spew("Setting serial parameters on port %s (fd %d).", serial->port,
		serial->fd);

	ret = sp_set_params(&serial->data, baudrate, bits, parity, stopbits,
			flowcontrol, rts, dtr);

	switch (ret)
	{
		case SP_ERR_ARG:
			sr_err("Invalid arguments for setting serial port parameters.");
			return SR_ERR_ARG;
		case SP_ERR_FAIL:
			error = sp_last_error_message();
			sr_err("Error setting serial port parameters: %s.", error);
			sp_free_error_message(error);
			return SR_ERR;
	}

	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;
		if (len < 1)
			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;
		}
		if (len < 1)
			g_usleep(byte_delay_us);
	}

	*buflen = ibuf;

	sr_err("Didn't find a valid packet (read %d bytes).", *buflen);

	return SR_ERR;
}
Commit	Line	Data
a1bb33af	1	/*
50985c20	2	* This file is part of the libsigrok project.
a1bb33af	3	*
c73d2ea4	4	* Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
b19f4622	5	* Copyright (C) 2010-2012 Uwe Hermann <uwe@hermann-uwe.de>
766456be	6	* Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
a1bb33af UH	7	*
	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.
	12	*
	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.
	17	*
	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/>.
	20	*/
	21
54b38f64	22	#include <string.h>
d02a535e	23	#include <stdlib.h>
a1bb33af	24	#include <glib.h>
a9bce5a5	25	#include <serialport.h>
45c59c8b BV	26	#include "libsigrok.h"
45c59c8b BV	27	#include "libsigrok-internal.h"
a1bb33af	28
29a27196 UH	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)
b19f4622	37
b19f4622 UH	38	/**
	39	* Open the specified serial port.
	40	*
299bdb24	41	* @param serial Previously initialized serial port structure.
a54dd31e UH	42	* @param flags Flags to use when opening the serial port. Possible flags
a54dd31e UH	43	* include SERIAL_RDWR, SERIAL_RDONLY, SERIAL_NONBLOCK.
b19f4622	44	*
299bdb24 BV	45	* If the serial structure contains a serialcomm string, it will be
	46	* passed to serial_set_paramstr() after the port is opened.
	47	*
	48	* @return SR_OK on success, SR_ERR on failure.
b19f4622	49	*/
299bdb24	50	SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
d02a535e	51	{
a9bce5a5 ML	52	int ret;
a9bce5a5 ML	53	char *error;
b19f4622	54
299bdb24 BV	55	if (!serial) {
	56	sr_dbg("Invalid serial port.");
	57	return SR_ERR;
	58	}
	59
	60	sr_spew("Opening serial port '%s' (flags %d).", serial->port, flags);
b19f4622	61
a9bce5a5 ML	62	ret = sp_open(&serial->data, serial->port, flags);
	63
	64	switch (ret)
	65	{
	66	case SP_ERR_ARG:
	67	sr_err("Attempt to open serial port with invalid parameters.");
	68	return SR_ERR_ARG;
	69	case SP_ERR_FAIL:
	70	error = sp_last_error_message();
	71	sr_err("Error opening port: %s.", error);
	72	sp_free_error_message(error);
	73	return SR_ERR;
a54dd31e UH	74	}
a54dd31e UH	75
a9bce5a5 ML	76	#ifndef _WIN32
a9bce5a5 ML	77	serial->fd = serial->data.fd;
926b866c	78	#endif
299bdb24 BV	79
	80	if (serial->serialcomm)
	81	return serial_set_paramstr(serial, serial->serialcomm);
	82	else
	83	return SR_OK;
d02a535e BV	84	}
d02a535e BV	85
b19f4622 UH	86	/**
	87	* Close the specified serial port.
	88	*
299bdb24	89	* @param serial Previously initialized serial port structure.
b19f4622	90	*
299bdb24	91	* @return SR_OK on success, SR_ERR on failure.
2119ab03	92	*/
299bdb24	93	SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
d02a535e	94	{
299bdb24	95	int ret;
a9bce5a5	96	char *error;
299bdb24 BV	97
	98	if (!serial) {
	99	sr_dbg("Invalid serial port.");
	100	return SR_ERR;
	101	}
	102
	103	if (serial->fd == -1) {
	104	sr_dbg("Cannot close unopened serial port %s (fd %d).",
	105	serial->port, serial->fd);
	106	return SR_ERR;
	107	}
	108
	109	sr_spew("Closing serial port %s (fd %d).", serial->port, serial->fd);
	110	ret = SR_OK;
b19f4622	111
a9bce5a5 ML	112	ret = sp_close(&serial->data);
	113
	114	switch (ret)
	115	{
	116	case SP_ERR_ARG:
	117	sr_err("Attempt to close an invalid serial port.");
	118	return SR_ERR_ARG;
	119	case SP_ERR_FAIL:
	120	error = sp_last_error_message();
	121	sr_err("Error closing port: %s.", error);
	122	sp_free_error_message(error);
	123	return SR_ERR;
b19f4622	124	}
299bdb24 BV	125
299bdb24 BV	126	serial->fd = -1;
b19f4622 UH	127
b19f4622 UH	128	return ret;
d02a535e BV	129	}
d02a535e BV	130
b19f4622	131	/**
299bdb24	132	* Flush serial port buffers.
b19f4622	133	*
299bdb24	134	* @param serial Previously initialized serial port structure.
b19f4622	135	*
299bdb24	136	* @return SR_OK on success, SR_ERR on failure.
1fdb75e1	137	*/
299bdb24	138	SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
06d64eb8	139	{
299bdb24	140	int ret;
a9bce5a5	141	char *error;
299bdb24 BV	142
	143	if (!serial) {
	144	sr_dbg("Invalid serial port.");
	145	return SR_ERR;
	146	}
	147
	148	if (serial->fd == -1) {
	149	sr_dbg("Cannot flush unopened serial port %s (fd %d).",
	150	serial->port, serial->fd);
	151	return SR_ERR;
	152	}
	153
	154	sr_spew("Flushing serial port %s (fd %d).", serial->port, serial->fd);
b19f4622	155
a9bce5a5 ML	156	ret = sp_flush(&serial->data);
	157
	158	switch (ret)
	159	{
	160	case SP_ERR_ARG:
	161	sr_err("Attempt to flush an invalid serial port.");
	162	return SR_ERR_ARG;
	163	case SP_ERR_FAIL:
	164	error = sp_last_error_message();
	165	sr_err("Error flushing port: %s.", error);
	166	sp_free_error_message(error);
	167	return SR_ERR;
299bdb24	168	}
b19f4622 UH	169
b19f4622 UH	170	return ret;
06d64eb8 BV	171	}
06d64eb8 BV	172
b19f4622	173	/**
2119ab03	174	* Write a number of bytes to the specified serial port.
b19f4622	175	*
299bdb24	176	* @param serial Previously initialized serial port structure.
b19f4622 UH	177	* @param buf Buffer containing the bytes to write.
	178	* @param count Number of bytes to write.
	179	*
	180	* @return The number of bytes written, or -1 upon failure.
2119ab03	181	*/
299bdb24 BV	182	SR_PRIV int serial_write(struct sr_serial_dev_inst *serial,
299bdb24 BV	183	const void *buf, size_t count)
2119ab03	184	{
299bdb24	185	ssize_t ret;
a9bce5a5	186	char *error;
299bdb24 BV	187
	188	if (!serial) {
	189	sr_dbg("Invalid serial port.");
	190	return -1;
	191	}
	192
	193	if (serial->fd == -1) {
	194	sr_dbg("Cannot use unopened serial port %s (fd %d).",
	195	serial->port, serial->fd);
	196	return -1;
	197	}
	198
a9bce5a5 ML	199	ret = sp_write(&serial->data, buf, count);
	200
	201	switch (ret)
	202	{
	203	case SP_ERR_ARG:
	204	sr_err("Attempted serial port write with invalid arguments.");
	205	return SR_ERR_ARG;
	206	case SP_ERR_FAIL:
	207	error = sp_last_error_message();
	208	sr_err("Write error: %s.", error);
	209	sp_free_error_message(error);
	210	return SR_ERR;
	211	}
	212
	213	sr_spew("Wrote %d/%d bytes (fd %d).", ret, count, serial->fd);
b19f4622 UH	214
b19f4622 UH	215	return ret;
2119ab03 UH	216	}
2119ab03 UH	217
b19f4622	218	/**
2119ab03	219	* Read a number of bytes from the specified serial port.
b19f4622	220	*
299bdb24	221	* @param serial Previously initialized serial port structure.
b19f4622 UH	222	* @param buf Buffer where to store the bytes that are read.
	223	* @param count The number of bytes to read.
	224	*
	225	* @return The number of bytes read, or -1 upon failure.
2119ab03	226	*/
299bdb24 BV	227	SR_PRIV int serial_read(struct sr_serial_dev_inst serial, void buf,
299bdb24 BV	228	size_t count)
2119ab03	229	{
299bdb24	230	ssize_t ret;
a9bce5a5	231	char *error;
299bdb24 BV	232
	233	if (!serial) {
	234	sr_dbg("Invalid serial port.");
	235	return -1;
	236	}
	237
	238	if (serial->fd == -1) {
	239	sr_dbg("Cannot use unopened serial port %s (fd %d).",
	240	serial->port, serial->fd);
	241	return -1;
	242	}
	243
a9bce5a5	244	ret = sp_read(&serial->data, buf, count);
2119ab03	245
a9bce5a5 ML	246	switch (ret)
	247	{
	248	case SP_ERR_ARG:
	249	sr_err("Attempted serial port read with invalid arguments.");
	250	return SR_ERR_ARG;
	251	case SP_ERR_FAIL:
	252	error = sp_last_error_message();
	253	sr_err("Read error: %s.", error);
	254	sp_free_error_message(error);
	255	return SR_ERR;
	256	}
	257
	258	sr_spew("Read %d/%d bytes (fd %d).", ret, count, serial->fd);
b19f4622 UH	259
b19f4622 UH	260	return ret;
2119ab03 UH	261	}
2119ab03 UH	262
b19f4622 UH	263	/**
	264	* Set serial parameters for the specified serial port.
	265	*
299bdb24	266	* @param serial Previously initialized serial port structure.
b19f4622 UH	267	* @param baudrate The baudrate to set.
	268	* @param bits The number of data bits to use.
	269	* @param parity The parity setting to use (0 = none, 1 = even, 2 = odd).
	270	* @param stopbits The number of stop bits to use (1 or 2).
	271	* @param flowcontrol The flow control settings to use (0 = none, 1 = RTS/CTS,
	272	* 2 = XON/XOFF).
2119ab03	273	*
b19f4622	274	* @return SR_OK upon success, SR_ERR upon failure.
1ff7712c	275	*/
299bdb24	276	SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
39e5d798 UH	277	int bits, int parity, int stopbits,
39e5d798 UH	278	int flowcontrol, int rts, int dtr)
d02a535e	279	{
a9bce5a5 ML	280	int ret;
	281	char *error;
	282
299bdb24 BV	283	if (!serial) {
	284	sr_dbg("Invalid serial port.");
	285	return SR_ERR;
	286	}
	287
	288	if (serial->fd == -1) {
	289	sr_dbg("Cannot configure unopened serial port %s (fd %d).",
39e5d798	290	serial->port, serial->fd);
299bdb24 BV	291	return SR_ERR;
	292	}
	293
	294	sr_spew("Setting serial parameters on port %s (fd %d).", serial->port,
39e5d798	295	serial->fd);
b19f4622	296
a9bce5a5 ML	297	ret = sp_set_params(&serial->data, baudrate, bits, parity, stopbits,
	298	flowcontrol, rts, dtr);
	299
	300	switch (ret)
	301	{
	302	case SP_ERR_ARG:
	303	sr_err("Invalid arguments for setting serial port parameters.");
	304	return SR_ERR_ARG;
	305	case SP_ERR_FAIL:
	306	error = sp_last_error_message();
	307	sr_err("Error setting serial port parameters: %s.", error);
	308	sp_free_error_message(error);
71caaad4	309	return SR_ERR;
700dcd5c UH	310	}
700dcd5c UH	311
e46b8fb1	312	return SR_OK;
d02a535e	313	}
792fc686	314
299bdb24 BV	315	/**
	316	* Set serial parameters for the specified serial port.
	317	*
	318	* @param serial Previously initialized serial port structure.
	319	* @param paramstr A serial communication parameters string, in the form
26ddb5ba	320	* of <speed>/<data bits><parity><stopbits><flow>, for example "9600/8n1" or
26ddb5ba	321	* "600/7o2" or "460800/8n1/flow=2" where flow is 0 for none, 1 for rts/cts and 2 for xon/xoff.
299bdb24 BV	322	*
	323	* @return SR_OK upon success, SR_ERR upon failure.
	324	*/
71caaad4	325	#define SERIAL_COMM_SPEC "^(\\d+)/([78])([neo])([12])(.*)$"
299bdb24 BV	326	SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
299bdb24 BV	327	const char *paramstr)
792fc686 BV	328	{
	329	GRegex *reg;
	330	GMatchInfo *match;
26ddb5ba	331	int speed, databits, parity, stopbits, flow, rts, dtr, i;
71caaad4	332	char mstr, opts, *kv;
792fc686	333
26ddb5ba	334	speed = databits = parity = stopbits = flow = 0;
71caaad4	335	rts = dtr = -1;
ea088bb6	336	sr_spew("Parsing parameters from \"%s\".", paramstr);
792fc686 BV	337	reg = g_regex_new(SERIAL_COMM_SPEC, 0, 0, NULL);
	338	if (g_regex_match(reg, paramstr, 0, &match)) {
	339	if ((mstr = g_match_info_fetch(match, 1)))
	340	speed = strtoul(mstr, NULL, 10);
	341	g_free(mstr);
	342	if ((mstr = g_match_info_fetch(match, 2)))
	343	databits = strtoul(mstr, NULL, 10);
	344	g_free(mstr);
	345	if ((mstr = g_match_info_fetch(match, 3))) {
	346	switch (mstr[0]) {
	347	case 'n':
	348	parity = SERIAL_PARITY_NONE;
	349	break;
	350	case 'e':
	351	parity = SERIAL_PARITY_EVEN;
	352	break;
	353	case 'o':
	354	parity = SERIAL_PARITY_ODD;
	355	break;
	356	}
	357	}
	358	g_free(mstr);
	359	if ((mstr = g_match_info_fetch(match, 4)))
	360	stopbits = strtoul(mstr, NULL, 10);
	361	g_free(mstr);
71caaad4 BV	362	if ((mstr = g_match_info_fetch(match, 5)) && mstr[0] != '\0') {
	363	if (mstr[0] != '/') {
	364	sr_dbg("missing separator before extra options");
	365	speed = 0;
	366	} else {
	367	/* A set of "key=value" options separated by / */
	368	opts = g_strsplit(mstr + 1, "/", 0);
	369	for (i = 0; opts[i]; i++) {
	370	kv = g_strsplit(opts[i], "=", 2);
	371	if (!strncmp(kv[0], "rts", 3)) {
	372	if (kv[1][0] == '1')
	373	rts = 1;
	374	else if (kv[1][0] == '0')
	375	rts = 0;
	376	else {
	377	sr_dbg("invalid value for rts: %c", kv[1][0]);
	378	speed = 0;
	379	}
	380	} else if (!strncmp(kv[0], "dtr", 3)) {
	381	if (kv[1][0] == '1')
	382	dtr = 1;
	383	else if (kv[1][0] == '0')
	384	dtr = 0;
	385	else {
	386	sr_dbg("invalid value for dtr: %c", kv[1][0]);
	387	speed = 0;
	388	}
26ddb5ba	389	} else if (!strncmp(kv[0], "flow", 4)) {
	390	if (kv[1][0] == '0')
	391	flow = 0;
	392	else if (kv[1][0] == '1')
	393	flow = 1;
	394	else if (kv[1][0] == '2')
	395	flow = 2;
	396	else {
	397	sr_dbg("invalid value for flow: %c", kv[1][0]);
	398	speed = 0;
	399	}
71caaad4 BV	400	}
	401	g_strfreev(kv);
	402	}
	403	g_strfreev(opts);
	404	}
	405	}
	406	g_free(mstr);
792fc686 BV	407	}
	408	g_match_info_unref(match);
	409	g_regex_unref(reg);
	410
ea088bb6 AG	411	if (speed) {
ea088bb6 AG	412	return serial_set_params(serial, speed, databits, parity,
26ddb5ba	413	stopbits, flow, rts, dtr);
ea088bb6 AG	414	} else {
ea088bb6 AG	415	sr_dbg("Could not infer speed from parameter string.");
792fc686	416	return SR_ERR_ARG;
ea088bb6	417	}
792fc686 BV	418	}
792fc686 BV	419
299bdb24 BV	420	/**
	421	* Read a line from the specified serial port.
	422	*
	423	* @param serial Previously initialized serial port structure.
	424	* @param buf Buffer where to store the bytes that are read.
	425	* @param buflen Size of the buffer.
	426	* @param timeout_ms How long to wait for a line to come in.
	427	*
	428	* Reading stops when CR of LR is found, which is stripped from the buffer.
	429	*
	430	* @return SR_OK on success, SR_ERR on failure.
	431	*/
	432	SR_PRIV int serial_readline(struct sr_serial_dev_inst serial, char *buf,
	433	int *buflen, gint64 timeout_ms)
6f22a8ef	434	{
b87f8504	435	gint64 start;
6f22a8ef UH	436	int maxlen, len;
6f22a8ef UH	437
299bdb24 BV	438	if (!serial \|\| serial->fd == -1) {
	439	sr_dbg("Invalid serial port.");
	440	return SR_ERR;
	441	}
	442
	443	if (serial->fd == -1) {
	444	sr_dbg("Cannot use unopened serial port %s (fd %d).",
	445	serial->port, serial->fd);
	446	return -1;
	447	}
	448
6f22a8ef UH	449	timeout_ms *= 1000;
	450	start = g_get_monotonic_time();
	451
	452	maxlen = *buflen;
	453	*buflen = len = 0;
	454	while(1) {
	455	len = maxlen - *buflen - 1;
	456	if (len < 1)
	457	break;
299bdb24	458	len = serial_read(serial, buf + buflen, 1);
6f22a8ef UH	459	if (len > 0) {
	460	*buflen += len;
	461	(buf + *buflen) = '\0';
318dd53c BV	462	if (buflen > 0 && ((buf + buflen - 1) == '\r'
	463	\|\| (buf + *buflen - 1) == '\n')) {
	464	/* Strip CR/LF and terminate. */
6f22a8ef UH	465	(buf + --*buflen) = '\0';
	466	break;
	467	}
	468	}
	469	if (g_get_monotonic_time() - start > timeout_ms)
	470	/* Timeout */
	471	break;
5715e84f DT	472	if (len < 1)
5715e84f DT	473	g_usleep(2000);
6f22a8ef	474	}
318dd53c BV	475	if (*buflen)
318dd53c BV	476	sr_dbg("Received %d: '%s'.", buflen, buf);
6f22a8ef UH	477
	478	return SR_OK;
	479	}
766456be UH	480
	481	/**
	482	* Try to find a valid packet in a serial data stream.
	483	*
	484	* @param serial Previously initialized serial port structure.
	485	* @param buf Buffer containing the bytes to write.
	486	* @param count Size of the buffer.
	487	* @param packet_size Size, in bytes, of a valid packet.
	488	* @param is_valid Callback that assesses whether the packet is valid or not.
	489	* @param timeout_ms The timeout after which, if no packet is detected, to
	490	* abort scanning.
	491	* @param baudrate The baudrate of the serial port. This parameter is not
	492	* critical, but it helps fine tune the serial port polling
	493	* delay.
	494	*
	495	* @return SR_OK if a valid packet is found within the given timeout,
	496	* SR_ERR upon failure.
	497	*/
	498	SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
	499	uint8_t buf, size_t buflen,
	500	size_t packet_size, packet_valid_t is_valid,
	501	uint64_t timeout_ms, int baudrate)
	502	{
	503	uint64_t start, time, byte_delay_us;
	504	size_t ibuf, i, maxlen;
	505	int len;
	506
	507	maxlen = *buflen;
	508
	509	sr_dbg("Detecting packets on FD %d (timeout = %" PRIu64
	510	"ms, baudrate = %d).", serial->fd, timeout_ms, baudrate);
	511
	512	if (maxlen < (packet_size / 2) ) {
	513	sr_err("Buffer size must be at least twice the packet size.");
	514	return SR_ERR;
	515	}
	516
766456be UH	517	/* Assume 8n1 transmission. That is 10 bits for every byte. */
	518	byte_delay_us = 10 * (1000000 / baudrate);
	519	start = g_get_monotonic_time();
	520
	521	i = ibuf = len = 0;
	522	while (ibuf < maxlen) {
	523	len = serial_read(serial, &buf[ibuf], 1);
	524	if (len > 0) {
	525	ibuf += len;
	526	} else if (len == 0) {
006dbe55	527	/* No logging, already done in serial_read(). */
766456be UH	528	} else {
	529	/* Error reading byte, but continuing anyway. */
	530	}
551c3d8c AG	531
	532	time = g_get_monotonic_time() - start;
	533	time /= 1000;
	534
766456be UH	535	if ((ibuf - i) >= packet_size) {
	536	/* We have at least a packet's worth of data. */
	537	if (is_valid(&buf[i])) {
766456be UH	538	sr_spew("Found valid %d-byte packet after "
	539	"%" PRIu64 "ms.", (ibuf - i), time);
	540	*buflen = ibuf;
	541	return SR_OK;
	542	} else {
	543	sr_spew("Got %d bytes, but not a valid "
	544	"packet.", (ibuf - i));
	545	}
	546	/* Not a valid packet. Continue searching. */
	547	i++;
	548	}
551c3d8c	549	if (time >= timeout_ms) {
766456be	550	/* Timeout */
551c3d8c	551	sr_dbg("Detection timed out after %dms.", time);
766456be UH	552	break;
766456be UH	553	}
5715e84f DT	554	if (len < 1)
5715e84f DT	555	g_usleep(byte_delay_us);
766456be UH	556	}
	557
	558	*buflen = ibuf;
	559
	560	sr_err("Didn't find a valid packet (read %d bytes).", *buflen);
	561
	562	return SR_ERR;
	563	}