[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);

	sp_get_port_by_name(serial->port, &serial->data);

	ret = sp_open(serial->data, 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
c9bc57b6 ML	62	sp_get_port_by_name(serial->port, &serial->data);
	63
	64	ret = sp_open(serial->data, flags);
a9bce5a5 ML	65
	66	switch (ret)
	67	{
	68	case SP_ERR_ARG:
	69	sr_err("Attempt to open serial port with invalid parameters.");
	70	return SR_ERR_ARG;
	71	case SP_ERR_FAIL:
	72	error = sp_last_error_message();
	73	sr_err("Error opening port: %s.", error);
	74	sp_free_error_message(error);
	75	return SR_ERR;
a54dd31e UH	76	}
a54dd31e UH	77
a9bce5a5	78	#ifndef _WIN32
c9bc57b6	79	serial->fd = serial->data->fd;
926b866c	80	#endif
299bdb24 BV	81
	82	if (serial->serialcomm)
	83	return serial_set_paramstr(serial, serial->serialcomm);
	84	else
	85	return SR_OK;
d02a535e BV	86	}
d02a535e BV	87
b19f4622 UH	88	/**
	89	* Close the specified serial port.
	90	*
299bdb24	91	* @param serial Previously initialized serial port structure.
b19f4622	92	*
299bdb24	93	* @return SR_OK on success, SR_ERR on failure.
2119ab03	94	*/
299bdb24	95	SR_PRIV int serial_close(struct sr_serial_dev_inst *serial)
d02a535e	96	{
299bdb24	97	int ret;
a9bce5a5	98	char *error;
299bdb24 BV	99
	100	if (!serial) {
	101	sr_dbg("Invalid serial port.");
	102	return SR_ERR;
	103	}
	104
	105	if (serial->fd == -1) {
	106	sr_dbg("Cannot close unopened serial port %s (fd %d).",
	107	serial->port, serial->fd);
	108	return SR_ERR;
	109	}
	110
	111	sr_spew("Closing serial port %s (fd %d).", serial->port, serial->fd);
	112	ret = SR_OK;
b19f4622	113
c9bc57b6	114	ret = sp_close(serial->data);
a9bce5a5 ML	115
	116	switch (ret)
	117	{
	118	case SP_ERR_ARG:
	119	sr_err("Attempt to close an invalid serial port.");
	120	return SR_ERR_ARG;
	121	case SP_ERR_FAIL:
	122	error = sp_last_error_message();
	123	sr_err("Error closing port: %s.", error);
	124	sp_free_error_message(error);
	125	return SR_ERR;
b19f4622	126	}
299bdb24 BV	127
299bdb24 BV	128	serial->fd = -1;
b19f4622 UH	129
b19f4622 UH	130	return ret;
d02a535e BV	131	}
d02a535e BV	132
b19f4622	133	/**
299bdb24	134	* Flush serial port buffers.
b19f4622	135	*
299bdb24	136	* @param serial Previously initialized serial port structure.
b19f4622	137	*
299bdb24	138	* @return SR_OK on success, SR_ERR on failure.
1fdb75e1	139	*/
299bdb24	140	SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
06d64eb8	141	{
299bdb24	142	int ret;
a9bce5a5	143	char *error;
299bdb24 BV	144
	145	if (!serial) {
	146	sr_dbg("Invalid serial port.");
	147	return SR_ERR;
	148	}
	149
	150	if (serial->fd == -1) {
	151	sr_dbg("Cannot flush unopened serial port %s (fd %d).",
	152	serial->port, serial->fd);
	153	return SR_ERR;
	154	}
	155
	156	sr_spew("Flushing serial port %s (fd %d).", serial->port, serial->fd);
b19f4622	157
c9bc57b6	158	ret = sp_flush(serial->data);
a9bce5a5 ML	159
	160	switch (ret)
	161	{
	162	case SP_ERR_ARG:
	163	sr_err("Attempt to flush an invalid serial port.");
	164	return SR_ERR_ARG;
	165	case SP_ERR_FAIL:
	166	error = sp_last_error_message();
	167	sr_err("Error flushing port: %s.", error);
	168	sp_free_error_message(error);
	169	return SR_ERR;
299bdb24	170	}
b19f4622 UH	171
b19f4622 UH	172	return ret;
06d64eb8 BV	173	}
06d64eb8 BV	174
b19f4622	175	/**
2119ab03	176	* Write a number of bytes to the specified serial port.
b19f4622	177	*
299bdb24	178	* @param serial Previously initialized serial port structure.
b19f4622 UH	179	* @param buf Buffer containing the bytes to write.
	180	* @param count Number of bytes to write.
	181	*
	182	* @return The number of bytes written, or -1 upon failure.
2119ab03	183	*/
299bdb24 BV	184	SR_PRIV int serial_write(struct sr_serial_dev_inst *serial,
299bdb24 BV	185	const void *buf, size_t count)
2119ab03	186	{
299bdb24	187	ssize_t ret;
a9bce5a5	188	char *error;
299bdb24 BV	189
	190	if (!serial) {
	191	sr_dbg("Invalid serial port.");
	192	return -1;
	193	}
	194
	195	if (serial->fd == -1) {
	196	sr_dbg("Cannot use unopened serial port %s (fd %d).",
	197	serial->port, serial->fd);
	198	return -1;
	199	}
	200
c9bc57b6	201	ret = sp_write(serial->data, buf, count);
a9bce5a5 ML	202
	203	switch (ret)
	204	{
	205	case SP_ERR_ARG:
	206	sr_err("Attempted serial port write with invalid arguments.");
	207	return SR_ERR_ARG;
	208	case SP_ERR_FAIL:
	209	error = sp_last_error_message();
	210	sr_err("Write error: %s.", error);
	211	sp_free_error_message(error);
	212	return SR_ERR;
	213	}
	214
	215	sr_spew("Wrote %d/%d bytes (fd %d).", ret, count, serial->fd);
b19f4622 UH	216
b19f4622 UH	217	return ret;
2119ab03 UH	218	}
2119ab03 UH	219
b19f4622	220	/**
2119ab03	221	* Read a number of bytes from the specified serial port.
b19f4622	222	*
299bdb24	223	* @param serial Previously initialized serial port structure.
b19f4622 UH	224	* @param buf Buffer where to store the bytes that are read.
	225	* @param count The number of bytes to read.
	226	*
	227	* @return The number of bytes read, or -1 upon failure.
2119ab03	228	*/
299bdb24 BV	229	SR_PRIV int serial_read(struct sr_serial_dev_inst serial, void buf,
299bdb24 BV	230	size_t count)
2119ab03	231	{
299bdb24	232	ssize_t ret;
a9bce5a5	233	char *error;
299bdb24 BV	234
	235	if (!serial) {
	236	sr_dbg("Invalid serial port.");
	237	return -1;
	238	}
	239
	240	if (serial->fd == -1) {
	241	sr_dbg("Cannot use unopened serial port %s (fd %d).",
	242	serial->port, serial->fd);
	243	return -1;
	244	}
	245
c9bc57b6	246	ret = sp_read(serial->data, buf, count);
2119ab03	247
a9bce5a5 ML	248	switch (ret)
	249	{
	250	case SP_ERR_ARG:
	251	sr_err("Attempted serial port read with invalid arguments.");
	252	return SR_ERR_ARG;
	253	case SP_ERR_FAIL:
	254	error = sp_last_error_message();
	255	sr_err("Read error: %s.", error);
	256	sp_free_error_message(error);
	257	return SR_ERR;
	258	}
	259
	260	sr_spew("Read %d/%d bytes (fd %d).", ret, count, serial->fd);
b19f4622 UH	261
b19f4622 UH	262	return ret;
2119ab03 UH	263	}
2119ab03 UH	264
b19f4622 UH	265	/**
	266	* Set serial parameters for the specified serial port.
	267	*
299bdb24	268	* @param serial Previously initialized serial port structure.
b19f4622 UH	269	* @param baudrate The baudrate to set.
	270	* @param bits The number of data bits to use.
	271	* @param parity The parity setting to use (0 = none, 1 = even, 2 = odd).
	272	* @param stopbits The number of stop bits to use (1 or 2).
	273	* @param flowcontrol The flow control settings to use (0 = none, 1 = RTS/CTS,
	274	* 2 = XON/XOFF).
2119ab03	275	*
b19f4622	276	* @return SR_OK upon success, SR_ERR upon failure.
1ff7712c	277	*/
299bdb24	278	SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
39e5d798 UH	279	int bits, int parity, int stopbits,
39e5d798 UH	280	int flowcontrol, int rts, int dtr)
d02a535e	281	{
a9bce5a5 ML	282	int ret;
	283	char *error;
	284
299bdb24 BV	285	if (!serial) {
	286	sr_dbg("Invalid serial port.");
	287	return SR_ERR;
	288	}
	289
	290	if (serial->fd == -1) {
	291	sr_dbg("Cannot configure unopened serial port %s (fd %d).",
39e5d798	292	serial->port, serial->fd);
299bdb24 BV	293	return SR_ERR;
	294	}
	295
	296	sr_spew("Setting serial parameters on port %s (fd %d).", serial->port,
39e5d798	297	serial->fd);
b19f4622	298
c9bc57b6	299	ret = sp_set_params(serial->data, baudrate, bits, parity, stopbits,
a9bce5a5 ML	300	flowcontrol, rts, dtr);
	301
	302	switch (ret)
	303	{
	304	case SP_ERR_ARG:
	305	sr_err("Invalid arguments for setting serial port parameters.");
	306	return SR_ERR_ARG;
	307	case SP_ERR_FAIL:
	308	error = sp_last_error_message();
	309	sr_err("Error setting serial port parameters: %s.", error);
	310	sp_free_error_message(error);
71caaad4	311	return SR_ERR;
700dcd5c UH	312	}
700dcd5c UH	313
e46b8fb1	314	return SR_OK;
d02a535e	315	}
792fc686	316
299bdb24 BV	317	/**
	318	* Set serial parameters for the specified serial port.
	319	*
	320	* @param serial Previously initialized serial port structure.
	321	* @param paramstr A serial communication parameters string, in the form
26ddb5ba	322	* of <speed>/<data bits><parity><stopbits><flow>, for example "9600/8n1" or
26ddb5ba	323	* "600/7o2" or "460800/8n1/flow=2" where flow is 0 for none, 1 for rts/cts and 2 for xon/xoff.
299bdb24 BV	324	*
	325	* @return SR_OK upon success, SR_ERR upon failure.
	326	*/
71caaad4	327	#define SERIAL_COMM_SPEC "^(\\d+)/([78])([neo])([12])(.*)$"
299bdb24 BV	328	SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
299bdb24 BV	329	const char *paramstr)
792fc686 BV	330	{
	331	GRegex *reg;
	332	GMatchInfo *match;
26ddb5ba	333	int speed, databits, parity, stopbits, flow, rts, dtr, i;
71caaad4	334	char mstr, opts, *kv;
792fc686	335
26ddb5ba	336	speed = databits = parity = stopbits = flow = 0;
71caaad4	337	rts = dtr = -1;
ea088bb6	338	sr_spew("Parsing parameters from \"%s\".", paramstr);
792fc686 BV	339	reg = g_regex_new(SERIAL_COMM_SPEC, 0, 0, NULL);
	340	if (g_regex_match(reg, paramstr, 0, &match)) {
	341	if ((mstr = g_match_info_fetch(match, 1)))
	342	speed = strtoul(mstr, NULL, 10);
	343	g_free(mstr);
	344	if ((mstr = g_match_info_fetch(match, 2)))
	345	databits = strtoul(mstr, NULL, 10);
	346	g_free(mstr);
	347	if ((mstr = g_match_info_fetch(match, 3))) {
	348	switch (mstr[0]) {
	349	case 'n':
	350	parity = SERIAL_PARITY_NONE;
	351	break;
	352	case 'e':
	353	parity = SERIAL_PARITY_EVEN;
	354	break;
	355	case 'o':
	356	parity = SERIAL_PARITY_ODD;
	357	break;
	358	}
	359	}
	360	g_free(mstr);
	361	if ((mstr = g_match_info_fetch(match, 4)))
	362	stopbits = strtoul(mstr, NULL, 10);
	363	g_free(mstr);
71caaad4 BV	364	if ((mstr = g_match_info_fetch(match, 5)) && mstr[0] != '\0') {
	365	if (mstr[0] != '/') {
	366	sr_dbg("missing separator before extra options");
	367	speed = 0;
	368	} else {
	369	/* A set of "key=value" options separated by / */
	370	opts = g_strsplit(mstr + 1, "/", 0);
	371	for (i = 0; opts[i]; i++) {
	372	kv = g_strsplit(opts[i], "=", 2);
	373	if (!strncmp(kv[0], "rts", 3)) {
	374	if (kv[1][0] == '1')
	375	rts = 1;
	376	else if (kv[1][0] == '0')
	377	rts = 0;
	378	else {
	379	sr_dbg("invalid value for rts: %c", kv[1][0]);
	380	speed = 0;
	381	}
	382	} else if (!strncmp(kv[0], "dtr", 3)) {
	383	if (kv[1][0] == '1')
	384	dtr = 1;
	385	else if (kv[1][0] == '0')
	386	dtr = 0;
	387	else {
	388	sr_dbg("invalid value for dtr: %c", kv[1][0]);
	389	speed = 0;
	390	}
26ddb5ba	391	} else if (!strncmp(kv[0], "flow", 4)) {
	392	if (kv[1][0] == '0')
	393	flow = 0;
	394	else if (kv[1][0] == '1')
	395	flow = 1;
	396	else if (kv[1][0] == '2')
	397	flow = 2;
	398	else {
	399	sr_dbg("invalid value for flow: %c", kv[1][0]);
	400	speed = 0;
	401	}
71caaad4 BV	402	}
	403	g_strfreev(kv);
	404	}
	405	g_strfreev(opts);
	406	}
	407	}
	408	g_free(mstr);
792fc686 BV	409	}
	410	g_match_info_unref(match);
	411	g_regex_unref(reg);
	412
ea088bb6 AG	413	if (speed) {
ea088bb6 AG	414	return serial_set_params(serial, speed, databits, parity,
26ddb5ba	415	stopbits, flow, rts, dtr);
ea088bb6 AG	416	} else {
ea088bb6 AG	417	sr_dbg("Could not infer speed from parameter string.");
792fc686	418	return SR_ERR_ARG;
ea088bb6	419	}
792fc686 BV	420	}
792fc686 BV	421
299bdb24 BV	422	/**
	423	* Read a line from the specified serial port.
	424	*
	425	* @param serial Previously initialized serial port structure.
	426	* @param buf Buffer where to store the bytes that are read.
	427	* @param buflen Size of the buffer.
	428	* @param timeout_ms How long to wait for a line to come in.
	429	*
	430	* Reading stops when CR of LR is found, which is stripped from the buffer.
	431	*
	432	* @return SR_OK on success, SR_ERR on failure.
	433	*/
	434	SR_PRIV int serial_readline(struct sr_serial_dev_inst serial, char *buf,
	435	int *buflen, gint64 timeout_ms)
6f22a8ef	436	{
b87f8504	437	gint64 start;
6f22a8ef UH	438	int maxlen, len;
6f22a8ef UH	439
299bdb24 BV	440	if (!serial \|\| serial->fd == -1) {
	441	sr_dbg("Invalid serial port.");
	442	return SR_ERR;
	443	}
	444
	445	if (serial->fd == -1) {
	446	sr_dbg("Cannot use unopened serial port %s (fd %d).",
	447	serial->port, serial->fd);
	448	return -1;
	449	}
	450
6f22a8ef UH	451	timeout_ms *= 1000;
	452	start = g_get_monotonic_time();
	453
	454	maxlen = *buflen;
	455	*buflen = len = 0;
	456	while(1) {
	457	len = maxlen - *buflen - 1;
	458	if (len < 1)
	459	break;
299bdb24	460	len = serial_read(serial, buf + buflen, 1);
6f22a8ef UH	461	if (len > 0) {
	462	*buflen += len;
	463	(buf + *buflen) = '\0';
318dd53c BV	464	if (buflen > 0 && ((buf + buflen - 1) == '\r'
	465	\|\| (buf + *buflen - 1) == '\n')) {
	466	/* Strip CR/LF and terminate. */
6f22a8ef UH	467	(buf + --*buflen) = '\0';
	468	break;
	469	}
	470	}
	471	if (g_get_monotonic_time() - start > timeout_ms)
	472	/* Timeout */
	473	break;
5715e84f DT	474	if (len < 1)
5715e84f DT	475	g_usleep(2000);
6f22a8ef	476	}
318dd53c BV	477	if (*buflen)
318dd53c BV	478	sr_dbg("Received %d: '%s'.", buflen, buf);
6f22a8ef UH	479
	480	return SR_OK;
	481	}
766456be UH	482
	483	/**
	484	* Try to find a valid packet in a serial data stream.
	485	*
	486	* @param serial Previously initialized serial port structure.
	487	* @param buf Buffer containing the bytes to write.
	488	* @param count Size of the buffer.
	489	* @param packet_size Size, in bytes, of a valid packet.
	490	* @param is_valid Callback that assesses whether the packet is valid or not.
	491	* @param timeout_ms The timeout after which, if no packet is detected, to
	492	* abort scanning.
	493	* @param baudrate The baudrate of the serial port. This parameter is not
	494	* critical, but it helps fine tune the serial port polling
	495	* delay.
	496	*
	497	* @return SR_OK if a valid packet is found within the given timeout,
	498	* SR_ERR upon failure.
	499	*/
	500	SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
	501	uint8_t buf, size_t buflen,
	502	size_t packet_size, packet_valid_t is_valid,
	503	uint64_t timeout_ms, int baudrate)
	504	{
	505	uint64_t start, time, byte_delay_us;
	506	size_t ibuf, i, maxlen;
	507	int len;
	508
	509	maxlen = *buflen;
	510
	511	sr_dbg("Detecting packets on FD %d (timeout = %" PRIu64
	512	"ms, baudrate = %d).", serial->fd, timeout_ms, baudrate);
	513
	514	if (maxlen < (packet_size / 2) ) {
	515	sr_err("Buffer size must be at least twice the packet size.");
	516	return SR_ERR;
	517	}
	518
766456be UH	519	/* Assume 8n1 transmission. That is 10 bits for every byte. */
	520	byte_delay_us = 10 * (1000000 / baudrate);
	521	start = g_get_monotonic_time();
	522
	523	i = ibuf = len = 0;
	524	while (ibuf < maxlen) {
	525	len = serial_read(serial, &buf[ibuf], 1);
	526	if (len > 0) {
	527	ibuf += len;
	528	} else if (len == 0) {
006dbe55	529	/* No logging, already done in serial_read(). */
766456be UH	530	} else {
	531	/* Error reading byte, but continuing anyway. */
	532	}
551c3d8c AG	533
	534	time = g_get_monotonic_time() - start;
	535	time /= 1000;
	536
766456be UH	537	if ((ibuf - i) >= packet_size) {
	538	/* We have at least a packet's worth of data. */
	539	if (is_valid(&buf[i])) {
766456be UH	540	sr_spew("Found valid %d-byte packet after "
	541	"%" PRIu64 "ms.", (ibuf - i), time);
	542	*buflen = ibuf;
	543	return SR_OK;
	544	} else {
	545	sr_spew("Got %d bytes, but not a valid "
	546	"packet.", (ibuf - i));
	547	}
	548	/* Not a valid packet. Continue searching. */
	549	i++;
	550	}
551c3d8c	551	if (time >= timeout_ms) {
766456be	552	/* Timeout */
551c3d8c	553	sr_dbg("Detection timed out after %dms.", time);
766456be UH	554	break;
766456be UH	555	}
5715e84f DT	556	if (len < 1)
5715e84f DT	557	g_usleep(byte_delay_us);
766456be UH	558	}
	559
	560	*buflen = ibuf;
	561
	562	sr_err("Didn't find a valid packet (read %d bytes).", *buflen);
	563
	564	return SR_ERR;
	565	}