X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=src%2Fserial.c;h=aca99d9988b725830a9251472231341be54c626c;hb=1ac8c2181b0390c601278ad05bab93dd1c801734;hp=9a9a0d94fd3b3058e84ba74202db681de8397885;hpb=155b680da482cea2381becb73c51cfb838bff31e;p=libsigrok.git

diff --git a/src/serial.c b/src/serial.c
index 9a9a0d94..aca99d99 100644
--- a/src/serial.c
+++ b/src/serial.c
@@ -4,6 +4,7 @@
  * 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>
+ * Copyright (C) 2014 Uffe Jakobsen <uffe@uffe.org>
  *
  * 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
@@ -19,34 +20,69 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <config.h>
 #include <string.h>
 #include <stdlib.h>
 #include <glib.h>
 #include <glib/gstdio.h>
+#ifdef HAVE_LIBSERIALPORT
 #include <libserialport.h>
-#include "libsigrok.h"
+#endif
+#include <libsigrok/libsigrok.h>
 #include "libsigrok-internal.h"
+#ifdef _WIN32
+#include <windows.h> /* for HANDLE */
+#endif
 
+/** @cond PRIVATE */
 #define LOG_PREFIX "serial"
+/** @endcond */
+
+/**
+ * @file
+ *
+ * Serial port handling.
+ */
+
+/**
+ * @defgroup grp_serial Serial port handling
+ *
+ * Serial port handling functions.
+ *
+ * @{
+ */
+
+#ifdef HAVE_SERIAL_COMM
+
+/* See if a (assumed opened) serial port is of any supported type. */
+static int dev_is_supported(struct sr_serial_dev_inst *serial)
+{
+	if (!serial)
+		return 0;
+	if (!serial->lib_funcs)
+		return 0;
+
+	return 1;
+}
 
 /**
  * Open the specified serial port.
  *
  * @param serial Previously initialized serial port structure.
  * @param[in] flags Flags to use when opening the serial port. Possible flags
- *              include SERIAL_RDWR, SERIAL_RDONLY, SERIAL_NONBLOCK.
+ *                  include SERIAL_RDWR, SERIAL_RDONLY.
  *
  * If the serial structure contains a serialcomm string, it will be
  * passed to serial_set_paramstr() after the port is opened.
  *
  * @retval SR_OK Success.
  * @retval SR_ERR Failure.
+ *
+ * @private
  */
 SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
 {
 	int ret;
-	char *error;
-	int sp_flags = 0;
 
 	if (!serial) {
 		sr_dbg("Invalid serial port.");
@@ -55,28 +91,20 @@ SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
 
 	sr_spew("Opening serial port '%s' (flags %d).", serial->port, flags);
 
-	sp_get_port_by_name(serial->port, &serial->data);
-
-	if (flags & SERIAL_RDWR)
-		sp_flags = (SP_MODE_READ | SP_MODE_WRITE);
-	else if (flags & SERIAL_RDONLY)
-		sp_flags = SP_MODE_READ;
+	/* Default to the libserialport transport layer. */
+	serial->lib_funcs = ser_lib_funcs_libsp;
+	if (!serial->lib_funcs)
+		return SR_ERR_NA;
 
-	serial->nonblocking = (flags & SERIAL_NONBLOCK) ? 1 : 0;
-
-	ret = sp_open(serial->data, sp_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 (%d): %s.",
-			sp_last_error_code(), error);
-		sp_free_error_message(error);
-		return SR_ERR;
-	}
+	/*
+	 * Run the transport's open routine. Setup the bitrate and the
+	 * UART frame format.
+	 */
+	if (!serial->lib_funcs->open)
+		return SR_ERR_NA;
+	ret = serial->lib_funcs->open(serial, flags);
+	if (ret != SR_OK)
+		return ret;
 
 	if (serial->serialcomm)
 		return serial_set_paramstr(serial, serial->serialcomm);
@@ -91,234 +119,217 @@ SR_PRIV int serial_open(struct sr_serial_dev_inst *serial, int flags)
  *
  * @retval SR_OK Success.
  * @retval SR_ERR Failure.
+ *
+ * @private
  */
 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->data) {
-		sr_dbg("Cannot close unopened serial port %s.", serial->port);
-		return SR_ERR;
-	}
-
 	sr_spew("Closing serial port %s.", serial->port);
 
-	ret = sp_close(serial->data);
+	if (!serial->lib_funcs || !serial->lib_funcs->close)
+		return SR_ERR_NA;
 
-	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 (%d): %s.",
-			sp_last_error_code(), error);
-		sp_free_error_message(error);
+	return serial->lib_funcs->close(serial);
+}
+
+/**
+ * Flush serial port buffers. Empty buffers, discard pending RX and TX data.
+ *
+ * @param serial Previously initialized serial port structure.
+ *
+ * @retval SR_OK Success.
+ * @retval SR_ERR Failure.
+ *
+ * @private
+ */
+SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
+{
+	if (!serial) {
+		sr_dbg("Invalid serial port.");
 		return SR_ERR;
 	}
 
-	sp_free_port(serial->data);
-	serial->data = NULL;
+	sr_spew("Flushing serial port %s.", serial->port);
 
-	return SR_OK;
+	if (!serial->lib_funcs || !serial->lib_funcs->flush)
+		return SR_ERR_NA;
+
+	return serial->lib_funcs->flush(serial);
 }
 
 /**
- * Flush serial port buffers.
+ * Drain serial port buffers. Wait for pending TX data to be sent.
  *
  * @param serial Previously initialized serial port structure.
  *
  * @retval SR_OK Success.
  * @retval SR_ERR Failure.
+ *
+ * @private
  */
-SR_PRIV int serial_flush(struct sr_serial_dev_inst *serial)
+SR_PRIV int serial_drain(struct sr_serial_dev_inst *serial)
 {
-	int ret;
-	char *error;
-
 	if (!serial) {
 		sr_dbg("Invalid serial port.");
 		return SR_ERR;
 	}
 
-	if (!serial->data) {
-		sr_dbg("Cannot flush unopened serial port %s.", serial->port);
-		return SR_ERR;
-	}
+	sr_spew("Draining serial port %s.", serial->port);
 
-	sr_spew("Flushing serial port %s.", serial->port);
+	if (!serial->lib_funcs || !serial->lib_funcs->drain)
+		return SR_ERR_NA;
+
+	return serial->lib_funcs->drain(serial);
+}
 
-	ret = sp_flush(serial->data, SP_BUF_BOTH);
+/**
+ * Check for available receive data.
+ *
+ * @param[in] serial Previously opened serial port instance.
+ *
+ * @returns The number of (known) available RX data bytes.
+ *
+ * Returns 0 if no receive data is available, or if the amount of
+ * available receive data cannot get determined.
+ */
+SR_PRIV size_t serial_has_receive_data(struct sr_serial_dev_inst *serial)
+{
+	size_t lib_count;
 
-	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 (%d): %s.",
-			sp_last_error_code(), error);
-		sp_free_error_message(error);
-		return SR_ERR;
-	}
+	if (!serial)
+		return 0;
 
-	return SR_OK;
+	lib_count = 0;
+	if (serial->lib_funcs && serial->lib_funcs->get_rx_avail)
+		lib_count = serial->lib_funcs->get_rx_avail(serial);
+
+	return lib_count;
 }
 
 static int _serial_write(struct sr_serial_dev_inst *serial,
-		const void *buf, size_t count, int nonblocking)
+	const void *buf, size_t count,
+	int nonblocking, unsigned int timeout_ms)
 {
 	ssize_t ret;
-	char *error;
 
 	if (!serial) {
 		sr_dbg("Invalid serial port.");
 		return SR_ERR;
 	}
 
-	if (!serial->data) {
-		sr_dbg("Cannot use unopened serial port %s.", serial->port);
-		return SR_ERR;
-	}
-
-	if (nonblocking)
-		ret = sp_nonblocking_write(serial->data, buf, count);
-	else
-		ret = sp_blocking_write(serial->data, buf, count, 0);
-
-	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 (%d): %s.", sp_last_error_code(), error);
-		sp_free_error_message(error);
-		return SR_ERR;
-	}
-
-	sr_spew("Wrote %d/%d bytes.", ret, count);
+	if (!serial->lib_funcs || !serial->lib_funcs->write)
+		return SR_ERR_NA;
+	ret = serial->lib_funcs->write(serial, buf, count,
+		nonblocking, timeout_ms);
+	sr_spew("Wrote %zd/%zu bytes.", ret, count);
 
 	return ret;
 }
 
 /**
- * Write a number of bytes to the specified serial port.
+ * Write a number of bytes to the specified serial port, blocking until finished.
  *
  * @param serial Previously initialized serial port structure.
  * @param[in] buf Buffer containing the bytes to write.
  * @param[in] count Number of bytes to write.
+ * @param[in] timeout_ms Timeout in ms, or 0 for no timeout.
  *
  * @retval SR_ERR_ARG Invalid argument.
  * @retval SR_ERR Other error.
- * @retval other The number of bytes written.
- */
-SR_PRIV int serial_write(struct sr_serial_dev_inst *serial,
-		const void *buf, size_t count)
-{
-	return _serial_write(serial, buf, count, serial->nonblocking);
-}
-
-/**
- * Write a number of bytes to the specified serial port, blocking until finished.
- * @copydetails serial_write()
+ * @retval other The number of bytes written. If this is less than the number
+ * specified in the call, the timeout was reached.
+ *
+ * @private
  */
 SR_PRIV int serial_write_blocking(struct sr_serial_dev_inst *serial,
-		const void *buf, size_t count)
+	const void *buf, size_t count, unsigned int timeout_ms)
 {
-	return _serial_write(serial, buf, count, 0);
+	return _serial_write(serial, buf, count, 0, timeout_ms);
 }
 
 /**
  * Write a number of bytes to the specified serial port, return immediately.
- * @copydetails serial_write()
-*/
+ *
+ * @param serial Previously initialized serial port structure.
+ * @param[in] buf Buffer containing the bytes to write.
+ * @param[in] count Number of bytes to write.
+ *
+ * @retval SR_ERR_ARG Invalid argument.
+ * @retval SR_ERR Other error.
+ * @retval other The number of bytes written.
+ *
+ * @private
+ */
 SR_PRIV int serial_write_nonblocking(struct sr_serial_dev_inst *serial,
-		const void *buf, size_t count)
+	const void *buf, size_t count)
 {
-	return _serial_write(serial, buf, count, 1);
+	return _serial_write(serial, buf, count, 1, 0);
 }
 
-static int _serial_read(struct sr_serial_dev_inst *serial, void *buf,
-		size_t count, int nonblocking)
+static int _serial_read(struct sr_serial_dev_inst *serial,
+	void *buf, size_t count, int nonblocking, unsigned int timeout_ms)
 {
 	ssize_t ret;
-	char *error;
 
 	if (!serial) {
 		sr_dbg("Invalid serial port.");
 		return SR_ERR;
 	}
 
-	if (!serial->data) {
-		sr_dbg("Cannot use unopened serial port %s.", serial->port);
-		return SR_ERR;
-	}
-
-	if (nonblocking)
-		ret = sp_nonblocking_read(serial->data, buf, count);
-	else
-		ret = sp_blocking_read(serial->data, buf, count, 0);
-
-	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 (%d): %s.", sp_last_error_code(), error);
-		sp_free_error_message(error);
-		return SR_ERR;
-	}
-
+	if (!serial->lib_funcs || !serial->lib_funcs->read)
+		return SR_ERR_NA;
+	ret = serial->lib_funcs->read(serial, buf, count,
+		nonblocking, timeout_ms);
 	if (ret > 0)
-		sr_spew("Read %d/%d bytes.", ret, count);
+		sr_spew("Read %zd/%zu bytes.", ret, count);
 
 	return ret;
 }
 
 /**
- * Read a number of bytes from the specified serial port.
+ * Read a number of bytes from the specified serial port, block until finished.
  *
  * @param serial Previously initialized serial port structure.
  * @param buf Buffer where to store the bytes that are read.
  * @param[in] count The number of bytes to read.
+ * @param[in] timeout_ms Timeout in ms, or 0 for no timeout.
  *
  * @retval SR_ERR_ARG Invalid argument.
- * @retval SR_ERR     Other error.
- * @retval other      The number of bytes read.
- */
-SR_PRIV int serial_read(struct sr_serial_dev_inst *serial, void *buf,
-		size_t count)
-{
-	return _serial_read(serial, buf, count, serial->nonblocking);
-}
-
-/**
- * Read a number of bytes from the specified serial port, block until finished.
- * @copydetails serial_read()
+ * @retval SR_ERR Other error.
+ * @retval other The number of bytes read. If this is less than the number
+ * requested, the timeout was reached.
+ *
+ * @private
  */
-SR_PRIV int serial_read_blocking(struct sr_serial_dev_inst *serial, void *buf,
-		size_t count)
+SR_PRIV int serial_read_blocking(struct sr_serial_dev_inst *serial,
+	void *buf, size_t count, unsigned int timeout_ms)
 {
-	return _serial_read(serial, buf, count, 0);
+	return _serial_read(serial, buf, count, 0, timeout_ms);
 }
 
 /**
  * Try to read up to @a count bytes from the specified serial port, return
  * immediately with what's available.
- * @copydetails serial_read()
+ *
+ * @param serial Previously initialized serial port structure.
+ * @param buf Buffer where to store the bytes that are read.
+ * @param[in] count The number of bytes to read.
+ *
+ * @retval SR_ERR_ARG Invalid argument.
+ * @retval SR_ERR Other error.
+ * @retval other The number of bytes read.
+ *
+ * @private
  */
-SR_PRIV int serial_read_nonblocking(struct sr_serial_dev_inst *serial, void *buf,
-		size_t count)
+SR_PRIV int serial_read_nonblocking(struct sr_serial_dev_inst *serial,
+	void *buf, size_t count)
 {
-	return _serial_read(serial, buf, count, 1);
+	return _serial_read(serial, buf, count, 1, 0);
 }
 
 /**
@@ -330,72 +341,45 @@ SR_PRIV int serial_read_nonblocking(struct sr_serial_dev_inst *serial, void *buf
  * @param[in] parity The parity setting to use (0 = none, 1 = even, 2 = odd).
  * @param[in] stopbits The number of stop bits to use (1 or 2).
  * @param[in] flowcontrol The flow control settings to use (0 = none,
- *                      1 = RTS/CTS, 2 = XON/XOFF).
+ *                        1 = RTS/CTS, 2 = XON/XOFF).
  * @param[in] rts Status of RTS line (0 or 1; required by some interfaces).
  * @param[in] dtr Status of DTR line (0 or 1; required by some interfaces).
  *
  * @retval SR_OK Success.
  * @retval SR_ERR Failure.
+ *
+ * @private
  */
-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)
+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;
-	struct sp_port_config *config;
 
 	if (!serial) {
 		sr_dbg("Invalid serial port.");
 		return SR_ERR;
 	}
 
-	if (!serial->data) {
-		sr_dbg("Cannot configure unopened serial port %s.", serial->port);
-		return SR_ERR;
-	}
-
 	sr_spew("Setting serial parameters on port %s.", serial->port);
 
-	sp_new_config(&config);
-	sp_set_config_baudrate(config, baudrate);
-	sp_set_config_bits(config, bits);
-	switch (parity) {
-	case 0:
-		sp_set_config_parity(config, SP_PARITY_NONE);
-		break;
-	case 1:
-		sp_set_config_parity(config, SP_PARITY_EVEN);
-		break;
-	case 2:
-		sp_set_config_parity(config, SP_PARITY_ODD);
-		break;
-	default:
-		return SR_ERR_ARG;
-	}
-	sp_set_config_stopbits(config, stopbits);
-	sp_set_config_rts(config, flowcontrol == 1 ? SP_RTS_FLOW_CONTROL : rts);
-	sp_set_config_cts(config, flowcontrol == 1 ? SP_CTS_FLOW_CONTROL : SP_CTS_IGNORE);
-	sp_set_config_dtr(config, dtr);
-	sp_set_config_dsr(config, SP_DSR_IGNORE);
-	sp_set_config_xon_xoff(config, flowcontrol == 2 ? SP_XONXOFF_INOUT : SP_XONXOFF_DISABLED);
-
-	ret = sp_set_config(serial->data, config);
-	sp_free_config(config);
-
-	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 (%d): %s.",
-			sp_last_error_code(), error);
-		sp_free_error_message(error);
-		return SR_ERR;
+	if (!serial->lib_funcs || !serial->lib_funcs->set_params)
+		return SR_ERR_NA;
+	ret = serial->lib_funcs->set_params(serial,
+		baudrate, bits, parity, stopbits,
+		flowcontrol, rts, dtr);
+	if (ret == SR_OK) {
+		serial->comm_params.bit_rate = baudrate;
+		serial->comm_params.data_bits = bits;
+		serial->comm_params.parity_bits = parity ? 1 : 0;
+		serial->comm_params.stop_bits = stopbits;
+		sr_dbg("DBG: %s() rate %d, %d%s%d", __func__,
+				baudrate, bits,
+				(parity == 0) ? "n" : "x",
+				stopbits);
 	}
 
-	return SR_OK;
+	return ret;
 }
 
 /**
@@ -404,7 +388,7 @@ SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
  * @param serial Previously initialized serial port structure.
  * @param[in] paramstr A serial communication parameters string of the form
  * "<baudrate>/<bits><parity><stopbits>{/<option>}".\n
- *  Examples: "9600/8n1", "600/7o2/dtr=1/rts=0" or "460800/8n1/flow=2".\n
+ * Examples: "9600/8n1", "600/7o2/dtr=1/rts=0" or "460800/8n1/flow=2".\n
  * \<baudrate\>=integer Baud rate.\n
  * \<bits\>=5|6|7|8 Number of data bits.\n
  * \<parity\>=n|e|o None, even, odd.\n
@@ -415,13 +399,18 @@ SR_PRIV int serial_set_params(struct sr_serial_dev_inst *serial, int baudrate,
  * rts=0|1 Set RTS off resp. on.\n
  * Please note that values and combinations of these parameters must be
  * supported by the concrete serial interface hardware and the drivers for it.
+ *
  * @retval SR_OK Success.
  * @retval SR_ERR Failure.
+ *
+ * @private
  */
 SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
-		const char *paramstr)
+	const char *paramstr)
 {
+/** @cond PRIVATE */
 #define SERIAL_COMM_SPEC "^(\\d+)/([5678])([neo])([12])(.*)$"
+/** @endcond */
 
 	GRegex *reg;
 	GMatchInfo *match;
@@ -442,13 +431,13 @@ SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
 		if ((mstr = g_match_info_fetch(match, 3))) {
 			switch (mstr[0]) {
 			case 'n':
-				parity = SERIAL_PARITY_NONE;
+				parity = SP_PARITY_NONE;
 				break;
 			case 'e':
-				parity = SERIAL_PARITY_EVEN;
+				parity = SP_PARITY_EVEN;
 				break;
 			case 'o':
-				parity = SERIAL_PARITY_ODD;
+				parity = SP_PARITY_ODD;
 				break;
 			}
 		}
@@ -517,20 +506,22 @@ SR_PRIV int serial_set_paramstr(struct sr_serial_dev_inst *serial,
 /**
  * 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[in] serial Previously initialized serial port structure.
+ * @param[out] buf Buffer where to store the bytes that are read.
+ * @param[in] buflen Size of the buffer.
  * @param[in] 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.
+ * Reading stops when CR or LF is found, which is stripped from the buffer.
  *
  * @retval SR_OK Success.
  * @retval SR_ERR Failure.
+ *
+ * @private
  */
-SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial, char **buf,
-		int *buflen, gint64 timeout_ms)
+SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial,
+	char **buf, int *buflen, gint64 timeout_ms)
 {
-	gint64 start;
+	gint64 start, remaining;
 	int maxlen, len;
 
 	if (!serial) {
@@ -538,21 +529,21 @@ SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial, char **buf,
 		return SR_ERR;
 	}
 
-	if (!serial->data) {
+	if (!dev_is_supported(serial)) {
 		sr_dbg("Cannot use unopened serial port %s.", serial->port);
 		return -1;
 	}
 
-	timeout_ms *= 1000;
 	start = g_get_monotonic_time();
+	remaining = timeout_ms;
 
 	maxlen = *buflen;
 	*buflen = len = 0;
-	while(1) {
+	while (1) {
 		len = maxlen - *buflen - 1;
 		if (len < 1)
 			break;
-		len = serial_read(serial, *buf + *buflen, 1);
+		len = serial_read_blocking(serial, *buf + *buflen, 1, remaining);
 		if (len > 0) {
 			*buflen += len;
 			*(*buf + *buflen) = '\0';
@@ -563,7 +554,9 @@ SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial, char **buf,
 				break;
 			}
 		}
-		if (g_get_monotonic_time() - start > timeout_ms)
+		/* Reduce timeout by time elapsed. */
+		remaining = timeout_ms - ((g_get_monotonic_time() - start) / 1000);
+		if (remaining <= 0)
 			/* Timeout */
 			break;
 		if (len < 1)
@@ -584,23 +577,25 @@ SR_PRIV int serial_readline(struct sr_serial_dev_inst *serial, char **buf,
  * @param[in] packet_size Size, in bytes, of a valid packet.
  * @param is_valid Callback that assesses whether the packet is valid or not.
  * @param[in] timeout_ms The timeout after which, if no packet is detected, to
- *                   abort scanning.
+ *                       abort scanning.
  * @param[in] baudrate The baudrate of the serial port. This parameter is not
- *                 critical, but it helps fine tune the serial port polling
- *                 delay.
+ *                     critical, but it helps fine tune the serial port polling
+ *                     delay.
  *
  * @retval SR_OK Valid packet was found within the given timeout.
  * @retval SR_ERR Failure.
+ *
+ * @private
  */
 SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
-				 uint8_t *buf, size_t *buflen,
-				 size_t packet_size,
-				 packet_valid_callback is_valid,
-				 uint64_t timeout_ms, int baudrate)
+	uint8_t *buf, size_t *buflen,
+	size_t packet_size,
+	packet_valid_callback is_valid,
+	uint64_t timeout_ms, int baudrate)
 {
 	uint64_t start, time, byte_delay_us;
 	size_t ibuf, i, maxlen;
-	int len;
+	ssize_t len;
 
 	maxlen = *buflen;
 
@@ -613,12 +608,12 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
 	}
 
 	/* Assume 8n1 transmission. That is 10 bits for every byte. */
-	byte_delay_us = 10 * (1000000 / baudrate);
+	byte_delay_us = 10 * ((1000 * 1000) / baudrate);
 	start = g_get_monotonic_time();
 
 	i = ibuf = len = 0;
 	while (ibuf < maxlen) {
-		len = serial_read(serial, &buf[ibuf], 1);
+		len = serial_read_nonblocking(serial, &buf[ibuf], 1);
 		if (len > 0) {
 			ibuf += len;
 		} else if (len == 0) {
@@ -631,14 +626,18 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
 		time /= 1000;
 
 		if ((ibuf - i) >= packet_size) {
+			GString *text;
 			/* We have at least a packet's worth of data. */
+			text = sr_hexdump_new(&buf[i], packet_size);
+			sr_spew("Trying packet: %s", text->str);
+			sr_hexdump_free(text);
 			if (is_valid(&buf[i])) {
-				sr_spew("Found valid %d-byte packet after "
+				sr_spew("Found valid %zu-byte packet after "
 					"%" PRIu64 "ms.", (ibuf - i), time);
 				*buflen = ibuf;
 				return SR_OK;
 			} else {
-				sr_spew("Got %d bytes, but not a valid "
+				sr_spew("Got %zu bytes, but not a valid "
 					"packet.", (ibuf - i));
 			}
 			/* Not a valid packet. Continue searching. */
@@ -646,7 +645,7 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
 		}
 		if (time >= timeout_ms) {
 			/* Timeout */
-			sr_dbg("Detection timed out after %dms.", time);
+			sr_dbg("Detection timed out after %" PRIu64 "ms.", time);
 			break;
 		}
 		if (len < 1)
@@ -655,7 +654,7 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
 
 	*buflen = ibuf;
 
-	sr_err("Didn't find a valid packet (read %d bytes).", *buflen);
+	sr_err("Didn't find a valid packet (read %zu bytes).", *buflen);
 
 	return SR_ERR;
 }
@@ -664,15 +663,17 @@ SR_PRIV int serial_stream_detect(struct sr_serial_dev_inst *serial,
  * Extract the serial device and options from the options linked list.
  *
  * @param options List of options passed from the command line.
- * @param serial_device Pointer where to store the exctracted serial device.
+ * @param serial_device Pointer where to store the extracted serial device.
  * @param serial_options Pointer where to store the optional extracted serial
  * options.
  *
  * @return SR_OK if a serial_device is found, SR_ERR if no device is found. The
  * returned string should not be freed by the caller.
+ *
+ * @private
  */
-SR_PRIV int sr_serial_extract_options(GSList *options, const char **serial_device,
-				      const char **serial_options)
+SR_PRIV int sr_serial_extract_options(GSList *options,
+	const char **serial_device, const char **serial_options)
 {
 	GSList *l;
 	struct sr_config *src;
@@ -684,91 +685,134 @@ SR_PRIV int sr_serial_extract_options(GSList *options, const char **serial_devic
 		switch (src->key) {
 		case SR_CONF_CONN:
 			*serial_device = g_variant_get_string(src->data, NULL);
-			sr_dbg("Parsed serial device: %s", *serial_device);
+			sr_dbg("Parsed serial device: %s.", *serial_device);
 			break;
-
 		case SR_CONF_SERIALCOMM:
 			*serial_options = g_variant_get_string(src->data, NULL);
-			sr_dbg("Parsed serial options: %s", *serial_options);
+			sr_dbg("Parsed serial options: %s.", *serial_options);
 			break;
 		}
 	}
 
 	if (!*serial_device) {
-		sr_dbg("No serial device specified");
+		sr_dbg("No serial device specified.");
 		return SR_ERR;
 	}
 
 	return SR_OK;
 }
 
-#ifdef _WIN32
-typedef HANDLE event_handle;
-#else
-typedef int event_handle;
-#endif
-
+/** @private */
 SR_PRIV int serial_source_add(struct sr_session *session,
-		struct sr_serial_dev_inst *serial, int events, int timeout,
-		sr_receive_data_callback cb, void *cb_data)
+	struct sr_serial_dev_inst *serial, int events, int timeout,
+	sr_receive_data_callback cb, void *cb_data)
 {
-	enum sp_event mask = 0;
-	unsigned int i;
+	if ((events & (G_IO_IN | G_IO_ERR)) && (events & G_IO_OUT)) {
+		sr_err("Cannot poll input/error and output simultaneously.");
+		return SR_ERR_ARG;
+	}
 
-	if (sp_new_event_set(&serial->event_set) != SP_OK)
-		return SR_ERR;
+	if (!dev_is_supported(serial)) {
+		sr_err("Invalid serial port.");
+		return SR_ERR_ARG;
+	}
 
-	if (events & G_IO_IN)
-		mask |= SP_EVENT_RX_READY;
-	if (events & G_IO_OUT)
-		mask |= SP_EVENT_TX_READY;
-	if (events & G_IO_ERR)
-		mask |= SP_EVENT_ERROR;
+	if (!serial->lib_funcs || !serial->lib_funcs->setup_source_add)
+		return SR_ERR_NA;
 
-	if (sp_add_port_events(serial->event_set, serial->data, mask) != SP_OK) {
-		sp_free_event_set(serial->event_set);
-		return SR_ERR;
+	return serial->lib_funcs->setup_source_add(session, serial,
+		events, timeout, cb, cb_data);
+}
+
+/** @private */
+SR_PRIV int serial_source_remove(struct sr_session *session,
+	struct sr_serial_dev_inst *serial)
+{
+	if (!dev_is_supported(serial)) {
+		sr_err("Invalid serial port.");
+		return SR_ERR_ARG;
 	}
 
-	serial->pollfds = (GPollFD *) g_malloc0(sizeof(GPollFD) * serial->event_set->count);
+	if (!serial->lib_funcs || !serial->lib_funcs->setup_source_remove)
+		return SR_ERR_NA;
 
-	for (i = 0; i < serial->event_set->count; i++) {
+	return serial->lib_funcs->setup_source_remove(session, serial);
+}
 
-		serial->pollfds[i].fd = ((event_handle *) serial->event_set->handles)[i];
+/**
+ * Create/allocate a new sr_serial_port structure.
+ *
+ * @param name The OS dependent name of the serial port. Must not be NULL.
+ * @param description An end user friendly description for the serial port.
+ *                    Can be NULL (in that case the empty string is used
+ *                    as description).
+ *
+ * @return The newly allocated sr_serial_port struct.
+ */
+static struct sr_serial_port *sr_serial_new(const char *name,
+	const char *description)
+{
+	struct sr_serial_port *serial;
 
-		mask = serial->event_set->masks[i];
+	if (!name)
+		return NULL;
 
-		if (mask & SP_EVENT_RX_READY)
-			serial->pollfds[i].events |= G_IO_IN;
-		if (mask & SP_EVENT_TX_READY)
-			serial->pollfds[i].events |= G_IO_OUT;
-		if (mask & SP_EVENT_ERROR)
-			serial->pollfds[i].events |= G_IO_ERR;
+	serial = g_malloc0(sizeof(*serial));
+	serial->name = g_strdup(name);
+	serial->description = g_strdup(description ? description : "");
 
-		if (sr_session_source_add_pollfd(session, &serial->pollfds[i],
-					timeout, cb, cb_data) != SR_OK)
-			return SR_ERR;
-	}
+	return serial;
+}
 
-	return SR_OK;
+/**
+ * Free a previously allocated sr_serial_port structure.
+ *
+ * @param serial The sr_serial_port struct to free. Must not be NULL.
+ */
+SR_API void sr_serial_free(struct sr_serial_port *serial)
+{
+	if (!serial)
+		return;
+	g_free(serial->name);
+	g_free(serial->description);
+	g_free(serial);
 }
 
-SR_PRIV int serial_source_remove(struct sr_session *session,
-		struct sr_serial_dev_inst *serial)
+static GSList *append_port_list(GSList *devs, const char *name, const char *desc)
 {
-	unsigned int i;
+	return g_slist_append(devs, sr_serial_new(name, desc));
+}
 
-	for (i = 0; i < serial->event_set->count; i++)
-		if (sr_session_source_remove_pollfd(session, &serial->pollfds[i]) != SR_OK)
-			return SR_ERR;
+/**
+ * List available serial devices.
+ *
+ * @return A GSList of strings containing the path of the serial devices or
+ *         NULL if no serial device is found. The returned list must be freed
+ *         by the caller.
+ */
+SR_API GSList *sr_serial_list(const struct sr_dev_driver *driver)
+{
+	GSList *tty_devs;
+	GSList *(*list_func)(GSList *list, sr_ser_list_append_t append);
 
-	g_free(serial->pollfds);
-	sp_free_event_set(serial->event_set);
+	/* Currently unused, but will be used by some drivers later on. */
+	(void)driver;
 
-	serial->pollfds = NULL;
-	serial->event_set = NULL;
+	tty_devs = NULL;
+	if (ser_lib_funcs_libsp && ser_lib_funcs_libsp->list) {
+		list_func = ser_lib_funcs_libsp->list;
+		tty_devs = list_func(tty_devs, append_port_list);
+	}
 
-	return SR_OK;
+	return tty_devs;
+}
+
+static GSList *append_port_find(GSList *devs, const char *name)
+{
+	if (!name || !*name)
+		return devs;
+
+	return g_slist_append(devs, g_strdup(name));
 }
 
 /**
@@ -780,132 +824,60 @@ SR_PRIV int serial_source_remove(struct sr_session *session,
  * @return A GSList of strings containing the path of the serial device or
  *         NULL if no serial device is found. The returned list must be freed
  *         by the caller.
+ *
+ * @private
  */
 SR_PRIV GSList *sr_serial_find_usb(uint16_t vendor_id, uint16_t product_id)
 {
-#ifdef __linux__
-	const gchar *usb_dev;
-	const char device_tree[] = "/sys/bus/usb/devices/";
-	GDir *devices_dir, *device_dir;
-	GSList *l = NULL;
 	GSList *tty_devs;
-	GSList *matched_paths;
-	FILE *fd;
-	char tmp[5];
-	gchar *vendor_path, *product_path, *path_copy;
-	gchar *prefix, *subdir_path, *device_path, *tty_path;
-	unsigned long read_vendor_id, read_product_id;
-	const char *file;
-
-	l = NULL;
-	tty_devs = NULL;
-	matched_paths = NULL;
-
-	if (!(devices_dir = g_dir_open(device_tree, 0, NULL)))
-		return NULL;
-
-	/*
-	 * Find potential candidates using the vendor ID and product ID
-	 * and store them in matched_paths.
-	 */
-	while ((usb_dev = g_dir_read_name(devices_dir))) {
-		vendor_path = g_strconcat(device_tree,
-					  usb_dev, "/idVendor", NULL);
-		product_path = g_strconcat(device_tree,
-					   usb_dev, "/idProduct", NULL);
-
-		if (!g_file_test(vendor_path, G_FILE_TEST_EXISTS) ||
-		    !g_file_test(product_path, G_FILE_TEST_EXISTS))
-			goto skip_device;
-
-		if ((fd = g_fopen(vendor_path, "r")) == NULL)
-			goto skip_device;
-
-		if (fgets(tmp, sizeof(tmp), fd) == NULL) {
-			fclose(fd);
-			goto skip_device;
-		}
-		read_vendor_id = strtoul(tmp, NULL, 16);
-
-		fclose(fd);
-
-		if ((fd = g_fopen(product_path, "r")) == NULL)
-			goto skip_device;
-
-		if (fgets(tmp, sizeof(tmp), fd) == NULL) {
-			fclose(fd);
-			goto skip_device;
-		}
-		read_product_id = strtoul(tmp, NULL, 16);
+	GSList *(*find_func)(GSList *list, sr_ser_find_append_t append,
+			uint16_t vid, uint16_t pid);
 
-		fclose(fd);
-
-		if (vendor_id == read_vendor_id &&
-		    product_id == read_product_id) {
-			path_copy = g_strdup(usb_dev);
-			matched_paths = g_slist_prepend(matched_paths,
-							path_copy);
-		}
-
-skip_device:
-		g_free(vendor_path);
-		g_free(product_path);
+	tty_devs = NULL;
+	if (ser_lib_funcs_libsp && ser_lib_funcs_libsp->find_usb) {
+		find_func = ser_lib_funcs_libsp->find_usb;
+		tty_devs = find_func(tty_devs, append_port_find,
+			vendor_id, product_id);
 	}
-	g_dir_close(devices_dir);
-
-	/* For every matched device try to find a ttyUSBX subfolder. */
-	for (l = matched_paths; l; l = l->next) {
-		subdir_path = NULL;
-
-		device_path = g_strconcat(device_tree, l->data, NULL);
-
-		if (!(device_dir = g_dir_open(device_path, 0, NULL))) {
-			g_free(device_path);
-			continue;
-		}
-
-		prefix = g_strconcat(l->data, ":", NULL);
 
-		while ((file = g_dir_read_name(device_dir))) {
-			if (g_str_has_prefix(file, prefix)) {
-				subdir_path = g_strconcat(device_path,
-						"/", file, NULL);
-				break;
-			}
-		}
-		g_dir_close(device_dir);
+	return tty_devs;
+}
 
-		g_free(prefix);
-		g_free(device_path);
+/** @private */
+SR_PRIV int serial_timeout(struct sr_serial_dev_inst *port, int num_bytes)
+{
+	int bits, baud;
+	int ret;
+	int timeout_ms;
+
+	/* Get the bitrate and frame length. */
+	bits = baud = 0;
+	if (port->lib_funcs && port->lib_funcs->get_frame_format) {
+		ret = port->lib_funcs->get_frame_format(port, &baud, &bits);
+		if (ret != SR_OK)
+			bits = baud = 0;
+	} else {
+		baud = port->comm_params.bit_rate;
+		bits = 1 + port->comm_params.data_bits +
+			port->comm_params.parity_bits +
+			port->comm_params.stop_bits;
+	}
 
-		if (subdir_path) {
-			if (!(device_dir = g_dir_open(subdir_path, 0, NULL))) {
-				g_free(subdir_path);
-				continue;
-			}
-			g_free(subdir_path);
-
-			while ((file = g_dir_read_name(device_dir))) {
-				if (g_str_has_prefix(file, "ttyUSB")) {
-					tty_path = g_strconcat("/dev/",
-							       file, NULL);
-					sr_dbg("Found USB device %04x:%04x attached to %s.",
-					       vendor_id, product_id, tty_path);
-					tty_devs = g_slist_prepend(tty_devs,
-							tty_path);
-					break;
-				}
-			}
-			g_dir_close(device_dir);
-		}
+	/* Derive the timeout. Default to 1s. */
+	timeout_ms = 1000;
+	if (bits && baud) {
+		/* Throw in 10ms for misc OS overhead. */
+		timeout_ms = 10;
+		timeout_ms += ((1000.0 / baud) * bits) * num_bytes;
 	}
-	g_slist_free_full(matched_paths, g_free);
 
-	return tty_devs;
+	return timeout_ms;
+}
+
 #else
-	(void)vendor_id;
-	(void)product_id;
 
-	return NULL;
+/* TODO Put fallback.c content here? */
+
 #endif
-}
+
+/** @} */