X-Git-Url: http://sigrok.org/gitweb/?a=blobdiff_plain;f=serialport.c;h=80527be098a85eed8d624ce7ff8dd4e5dc594e12;hb=5f64c28551d7ee7dbecf5215cb75d63c3cf8303b;hp=9671731b58fdaf56a7e3ced53d7870584424ae30;hpb=5a8810e2b2e0ccd2567306469f7fc668337af415;p=libserialport.git

diff --git a/serialport.c b/serialport.c
index 9671731..80527be 100644
--- a/serialport.c
+++ b/serialport.c
@@ -24,7 +24,7 @@
 #include "libserialport.h"
 #include "libserialport_internal.h"
 
-const struct std_baudrate std_baudrates[] = {
+static const struct std_baudrate std_baudrates[] = {
 #ifdef _WIN32
 	/*
 	 * The baudrates 50/75/134/150/200/1800/230400/460800 do not seem to
@@ -44,6 +44,8 @@ const struct std_baudrate std_baudrates[] = {
 #endif
 };
 
+#define NUM_STD_BAUDRATES ARRAY_SIZE(std_baudrates)
+
 void (*sp_debug_handler)(const char *format, ...) = sp_default_debug_handler;
 
 static enum sp_return get_config(struct sp_port *port, struct port_data *data,
@@ -70,7 +72,7 @@ SP_API enum sp_return sp_get_port_by_name(const char *portname, struct sp_port *
 	if (!portname)
 		RETURN_ERROR(SP_ERR_ARG, "Null port name");
 
-	DEBUG("Building structure for port %s", portname);
+	DEBUG_FMT("Building structure for port %s", portname);
 
 	if (!(port = malloc(sizeof(struct sp_port))))
 		RETURN_ERROR(SP_ERR_MEM, "Port structure malloc failed");
@@ -85,6 +87,7 @@ SP_API enum sp_return sp_get_port_by_name(const char *portname, struct sp_port *
 	memcpy(port->name, portname, len);
 
 #ifdef _WIN32
+	port->usb_path = NULL;
 	port->hdl = INVALID_HANDLE_VALUE;
 #else
 	port->fd = -1;
@@ -120,27 +123,27 @@ SP_API char *sp_get_port_name(const struct sp_port *port)
 	if (!port)
 		return NULL;
 
-	RETURN_VALUE("%s", port->name);
+	RETURN_STRING(port->name);
 }
 
-SP_API char *sp_get_port_description(struct sp_port *port)
+SP_API char *sp_get_port_description(const struct sp_port *port)
 {
 	TRACE("%p", port);
 
 	if (!port || !port->description)
 		return NULL;
 
-	RETURN_VALUE("%s", port->description);
+	RETURN_STRING(port->description);
 }
 
-SP_API enum sp_transport sp_get_port_transport(struct sp_port *port)
+SP_API enum sp_transport sp_get_port_transport(const struct sp_port *port)
 {
 	TRACE("%p", port);
 
 	if (!port)
 		RETURN_ERROR(SP_ERR_ARG, "Null port");
 
-	RETURN_VALUE("%d", port->transport);
+	RETURN_INT(port->transport);
 }
 
 SP_API enum sp_return sp_get_port_usb_bus_address(const struct sp_port *port,
@@ -155,8 +158,10 @@ SP_API enum sp_return sp_get_port_usb_bus_address(const struct sp_port *port,
 	if (port->usb_bus < 0 || port->usb_address < 0)
 		RETURN_ERROR(SP_ERR_SUPP, "Bus and address values are not available");
 
-	if (usb_bus)      *usb_bus     = port->usb_bus;
-	if (usb_address)  *usb_address = port->usb_address;
+	if (usb_bus)
+		*usb_bus = port->usb_bus;
+	if (usb_address)
+		*usb_address = port->usb_address;
 
 	RETURN_OK();
 }
@@ -173,8 +178,10 @@ SP_API enum sp_return sp_get_port_usb_vid_pid(const struct sp_port *port,
 	if (port->usb_vid < 0 || port->usb_pid < 0)
 		RETURN_ERROR(SP_ERR_SUPP, "VID:PID values are not available");
 
-	if (usb_vid)  *usb_vid = port->usb_vid;
-	if (usb_pid)  *usb_pid = port->usb_pid;
+	if (usb_vid)
+		*usb_vid = port->usb_vid;
+	if (usb_pid)
+		*usb_pid = port->usb_pid;
 
 	RETURN_OK();
 }
@@ -186,7 +193,7 @@ SP_API char *sp_get_port_usb_manufacturer(const struct sp_port *port)
 	if (!port || port->transport != SP_TRANSPORT_USB || !port->usb_manufacturer)
 		return NULL;
 
-	RETURN_VALUE("%s", port->usb_manufacturer);
+	RETURN_STRING(port->usb_manufacturer);
 }
 
 SP_API char *sp_get_port_usb_product(const struct sp_port *port)
@@ -196,7 +203,7 @@ SP_API char *sp_get_port_usb_product(const struct sp_port *port)
 	if (!port || port->transport != SP_TRANSPORT_USB || !port->usb_product)
 		return NULL;
 
-	RETURN_VALUE("%s", port->usb_product);
+	RETURN_STRING(port->usb_product);
 }
 
 SP_API char *sp_get_port_usb_serial(const struct sp_port *port)
@@ -206,7 +213,7 @@ SP_API char *sp_get_port_usb_serial(const struct sp_port *port)
 	if (!port || port->transport != SP_TRANSPORT_USB || !port->usb_serial)
 		return NULL;
 
-	RETURN_VALUE("%s", port->usb_serial);
+	RETURN_STRING(port->usb_serial);
 }
 
 SP_API char *sp_get_port_bluetooth_address(const struct sp_port *port)
@@ -217,7 +224,7 @@ SP_API char *sp_get_port_bluetooth_address(const struct sp_port *port)
 	    || !port->bluetooth_address)
 		return NULL;
 
-	RETURN_VALUE("%s", port->bluetooth_address);
+	RETURN_STRING(port->bluetooth_address);
 }
 
 SP_API enum sp_return sp_get_port_handle(const struct sp_port *port,
@@ -227,6 +234,8 @@ SP_API enum sp_return sp_get_port_handle(const struct sp_port *port,
 
 	if (!port)
 		RETURN_ERROR(SP_ERR_ARG, "Null port");
+	if (!result_ptr)
+		RETURN_ERROR(SP_ERR_ARG, "Null result pointer");
 
 #ifdef _WIN32
 	HANDLE *handle_ptr = result_ptr;
@@ -257,7 +266,7 @@ SP_API enum sp_return sp_copy_port(const struct sp_port *port,
 
 	DEBUG("Copying port structure");
 
-	RETURN_VALUE("%p", sp_get_port_by_name(port->name, copy_ptr));
+	RETURN_INT(sp_get_port_by_name(port->name, copy_ptr));
 }
 
 SP_API void sp_free_port(struct sp_port *port)
@@ -315,39 +324,37 @@ fail:
 
 SP_API enum sp_return sp_list_ports(struct sp_port ***list_ptr)
 {
+#ifndef NO_ENUMERATION
 	struct sp_port **list;
 	int ret;
+#endif
 
 	TRACE("%p", list_ptr);
 
 	if (!list_ptr)
 		RETURN_ERROR(SP_ERR_ARG, "Null result pointer");
 
+#ifdef NO_ENUMERATION
+	RETURN_ERROR(SP_ERR_SUPP, "Enumeration not supported on this platform");
+#else
 	DEBUG("Enumerating ports");
 
-	if (!(list = malloc(sizeof(struct sp_port **))))
+	if (!(list = malloc(sizeof(struct sp_port *))))
 		RETURN_ERROR(SP_ERR_MEM, "Port list malloc failed");
 
 	list[0] = NULL;
 
-#ifdef NO_ENUMERATION
-	ret = SP_ERR_SUPP;
-#else
 	ret = list_ports(&list);
-#endif
 
-	switch (ret) {
-	case SP_OK:
+	if (ret == SP_OK) {
 		*list_ptr = list;
-		RETURN_OK();
-	case SP_ERR_SUPP:
-		DEBUG_ERROR(SP_ERR_SUPP, "Enumeration not supported on this platform");
-	default:
-		if (list)
-			sp_free_port_list(list);
+	} else {
+		sp_free_port_list(list);
 		*list_ptr = NULL;
-		return ret;
 	}
+
+	RETURN_CODEVAL(ret);
+#endif
 }
 
 SP_API void sp_free_port_list(struct sp_port **list)
@@ -371,9 +378,9 @@ SP_API void sp_free_port_list(struct sp_port **list)
 }
 
 #define CHECK_PORT() do { \
-	if (port == NULL) \
+	if (!port) \
 		RETURN_ERROR(SP_ERR_ARG, "Null port"); \
-	if (port->name == NULL) \
+	if (!port->name) \
 		RETURN_ERROR(SP_ERR_ARG, "Null port name"); \
 } while (0)
 #ifdef _WIN32
@@ -392,6 +399,43 @@ SP_API void sp_free_port_list(struct sp_port **list)
 	CHECK_PORT_HANDLE(); \
 } while (0)
 
+#ifdef WIN32
+/** To be called after port receive buffer is emptied. */
+static enum sp_return restart_wait(struct sp_port *port)
+{
+	DWORD wait_result;
+
+	if (port->wait_running) {
+		/* Check status of running wait operation. */
+		if (GetOverlappedResult(port->hdl, &port->wait_ovl,
+				&wait_result, FALSE)) {
+			DEBUG("Previous wait completed");
+			port->wait_running = FALSE;
+		} else if (GetLastError() == ERROR_IO_INCOMPLETE) {
+			DEBUG("Previous wait still running");
+			RETURN_OK();
+		} else {
+			RETURN_FAIL("GetOverlappedResult() failed");
+		}
+	}
+
+	if (!port->wait_running) {
+		/* Start new wait operation. */
+		if (WaitCommEvent(port->hdl, &port->events,
+				&port->wait_ovl)) {
+			DEBUG("New wait returned, events already pending");
+		} else if (GetLastError() == ERROR_IO_PENDING) {
+			DEBUG("New wait running in background");
+			port->wait_running = TRUE;
+		} else {
+			RETURN_FAIL("WaitCommEvent() failed");
+		}
+	}
+
+	RETURN_OK();
+}
+#endif
+
 SP_API enum sp_return sp_open(struct sp_port *port, enum sp_mode flags)
 {
 	struct port_data data;
@@ -402,10 +446,10 @@ SP_API enum sp_return sp_open(struct sp_port *port, enum sp_mode flags)
 
 	CHECK_PORT();
 
-	if (flags > (SP_MODE_READ | SP_MODE_WRITE))
+	if (flags > SP_MODE_READ_WRITE)
 		RETURN_ERROR(SP_ERR_ARG, "Invalid flags");
 
-	DEBUG("Opening port %s", port->name);
+	DEBUG_FMT("Opening port %s", port->name);
 
 #ifdef _WIN32
 	DWORD desired_access = 0, flags_and_attributes = 0, errors;
@@ -430,7 +474,7 @@ SP_API enum sp_return sp_open(struct sp_port *port, enum sp_mode flags)
 	free(escaped_port_name);
 
 	if (port->hdl == INVALID_HANDLE_VALUE)
-		RETURN_FAIL("port CreateFile() failed");
+		RETURN_FAIL("Port CreateFile() failed");
 
 	/* All timeouts initially disabled. */
 	port->timeouts.ReadIntervalTimeout = 0;
@@ -465,21 +509,20 @@ SP_API enum sp_return sp_open(struct sp_port *port, enum sp_mode flags)
 		RETURN_FAIL("SetCommMask() failed");
 	}
 
-	/* Start background operation for RX and error events. */
-	if (WaitCommEvent(port->hdl, &port->events, &port->wait_ovl) == 0) {
-		if (GetLastError() != ERROR_IO_PENDING) {
-			sp_close(port);
-			RETURN_FAIL("WaitCommEvent() failed");
-		}
-	}
-
 	port->writing = FALSE;
+	port->wait_running = FALSE;
+
+	ret = restart_wait(port);
 
+	if (ret < 0) {
+		sp_close(port);
+		RETURN_CODEVAL(ret);
+	}
 #else
 	int flags_local = O_NONBLOCK | O_NOCTTY;
 
 	/* Map 'flags' to the OS-specific settings. */
-	if (flags & (SP_MODE_READ | SP_MODE_WRITE))
+	if ((flags & SP_MODE_READ_WRITE) == SP_MODE_READ_WRITE)
 		flags_local |= O_RDWR;
 	else if (flags & SP_MODE_READ)
 		flags_local |= O_RDONLY;
@@ -503,7 +546,7 @@ SP_API enum sp_return sp_open(struct sp_port *port, enum sp_mode flags)
 	data.dcb.fDsrSensitivity = FALSE;
 	data.dcb.fErrorChar = FALSE;
 	data.dcb.fNull = FALSE;
-	data.dcb.fAbortOnError = TRUE;
+	data.dcb.fAbortOnError = FALSE;
 #else
 	/* Turn off all fancy termios tricks, give us a raw channel. */
 	data.term.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IMAXBEL);
@@ -564,12 +607,12 @@ SP_API enum sp_return sp_close(struct sp_port *port)
 
 	CHECK_OPEN_PORT();
 
-	DEBUG("Closing port %s", port->name);
+	DEBUG_FMT("Closing port %s", port->name);
 
 #ifdef _WIN32
 	/* Returns non-zero upon success, 0 upon failure. */
 	if (CloseHandle(port->hdl) == 0)
-		RETURN_FAIL("port CloseHandle() failed");
+		RETURN_FAIL("Port CloseHandle() failed");
 	port->hdl = INVALID_HANDLE_VALUE;
 
 	/* Close event handles for overlapped structures. */
@@ -603,7 +646,8 @@ SP_API enum sp_return sp_flush(struct sp_port *port, enum sp_buffer buffers)
 
 	const char *buffer_names[] = {"no", "input", "output", "both"};
 
-	DEBUG("Flushing %s buffers on port %s", buffer_names[buffers], port->name);
+	DEBUG_FMT("Flushing %s buffers on port %s",
+		buffer_names[buffers], port->name);
 
 #ifdef _WIN32
 	DWORD flags = 0;
@@ -615,13 +659,16 @@ SP_API enum sp_return sp_flush(struct sp_port *port, enum sp_buffer buffers)
 	/* Returns non-zero upon success, 0 upon failure. */
 	if (PurgeComm(port->hdl, flags) == 0)
 		RETURN_FAIL("PurgeComm() failed");
+
+	if (buffers & SP_BUF_INPUT)
+		TRY(restart_wait(port));
 #else
 	int flags = 0;
-	if (buffers & SP_BUF_BOTH)
+	if (buffers == SP_BUF_BOTH)
 		flags = TCIOFLUSH;
-	else if (buffers & SP_BUF_INPUT)
+	else if (buffers == SP_BUF_INPUT)
 		flags = TCIFLUSH;
-	else if (buffers & SP_BUF_OUTPUT)
+	else if (buffers == SP_BUF_OUTPUT)
 		flags = TCOFLUSH;
 
 	/* Returns 0 upon success, -1 upon failure. */
@@ -637,7 +684,7 @@ SP_API enum sp_return sp_drain(struct sp_port *port)
 
 	CHECK_OPEN_PORT();
 
-	DEBUG("Draining port %s", port->name);
+	DEBUG_FMT("Draining port %s", port->name);
 
 #ifdef _WIN32
 	/* Returns non-zero upon success, 0 upon failure. */
@@ -668,22 +715,24 @@ SP_API enum sp_return sp_drain(struct sp_port *port)
 }
 
 SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
-                                        size_t count, unsigned int timeout)
+                                        size_t count, unsigned int timeout_ms)
 {
-	TRACE("%p, %p, %d, %d", port, buf, count, timeout);
+	TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
 
 	CHECK_OPEN_PORT();
 
 	if (!buf)
 		RETURN_ERROR(SP_ERR_ARG, "Null buffer");
 
-	if (timeout)
-		DEBUG("Writing %d bytes to port %s, timeout %d ms", count, port->name, timeout);
+	if (timeout_ms)
+		DEBUG_FMT("Writing %d bytes to port %s, timeout %d ms",
+			count, port->name, timeout_ms);
 	else
-		DEBUG("Writing %d bytes to port %s, no timeout", count, port->name);
+		DEBUG_FMT("Writing %d bytes to port %s, no timeout",
+			count, port->name);
 
 	if (count == 0)
-		RETURN_VALUE("0", 0);
+		RETURN_INT(0);
 
 #ifdef _WIN32
 	DWORD bytes_written = 0;
@@ -700,7 +749,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 	}
 
 	/* Set timeout. */
-	port->timeouts.WriteTotalTimeoutConstant = timeout;
+	port->timeouts.WriteTotalTimeoutConstant = timeout_ms;
 	if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
 		RETURN_FAIL("SetCommTimeouts() failed");
 
@@ -709,14 +758,14 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 		if (GetLastError() == ERROR_IO_PENDING) {
 			DEBUG("Waiting for write to complete");
 			GetOverlappedResult(port->hdl, &port->write_ovl, &bytes_written, TRUE);
-			DEBUG("Write completed, %d/%d bytes written", bytes_written, count);
-			RETURN_VALUE("%d", bytes_written);
+			DEBUG_FMT("Write completed, %d/%d bytes written", bytes_written, count);
+			RETURN_INT(bytes_written);
 		} else {
 			RETURN_FAIL("WriteFile() failed");
 		}
 	} else {
 		DEBUG("Write completed immediately");
-		RETURN_VALUE("%d", count);
+		RETURN_INT(count);
 	}
 #else
 	size_t bytes_written = 0;
@@ -725,31 +774,30 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 	fd_set fds;
 	int result;
 
-	if (timeout) {
+	if (timeout_ms) {
 		/* Get time at start of operation. */
 		gettimeofday(&start, NULL);
 		/* Define duration of timeout. */
-		delta.tv_sec = timeout / 1000;
-		delta.tv_usec = (timeout % 1000) * 1000;
+		delta.tv_sec = timeout_ms / 1000;
+		delta.tv_usec = (timeout_ms % 1000) * 1000;
 		/* Calculate time at which we should give up. */
 		timeradd(&start, &delta, &end);
 	}
 
 	/* Loop until we have written the requested number of bytes. */
-	while (bytes_written < count)
-	{
+	while (bytes_written < count) {
 		/* Wait until space is available. */
 		FD_ZERO(&fds);
 		FD_SET(port->fd, &fds);
-		if (timeout) {
+		if (timeout_ms) {
 			gettimeofday(&now, NULL);
 			if (timercmp(&now, &end, >)) {
-				DEBUG("write timed out");
-				RETURN_VALUE("%d", bytes_written);
+				DEBUG("Write timed out");
+				RETURN_INT(bytes_written);
 			}
 			timersub(&end, &now, &delta);
 		}
-		result = select(port->fd + 1, NULL, &fds, NULL, timeout ? &delta : NULL);
+		result = select(port->fd + 1, NULL, &fds, NULL, timeout_ms ? &delta : NULL);
 		if (result < 0) {
 			if (errno == EINTR) {
 				DEBUG("select() call was interrupted, repeating");
@@ -758,8 +806,8 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 				RETURN_FAIL("select() failed");
 			}
 		} else if (result == 0) {
-			DEBUG("write timed out");
-			RETURN_VALUE("%d", bytes_written);
+			DEBUG("Write timed out");
+			RETURN_INT(bytes_written);
 		}
 
 		/* Do write. */
@@ -778,7 +826,7 @@ SP_API enum sp_return sp_blocking_write(struct sp_port *port, const void *buf,
 		ptr += result;
 	}
 
-	RETURN_VALUE("%d", bytes_written);
+	RETURN_INT(bytes_written);
 #endif
 }
 
@@ -792,10 +840,10 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 	if (!buf)
 		RETURN_ERROR(SP_ERR_ARG, "Null buffer");
 
-	DEBUG("Writing up to %d bytes to port %s", count, port->name);
+	DEBUG_FMT("Writing up to %d bytes to port %s", count, port->name);
 
 	if (count == 0)
-		RETURN_VALUE("0", 0);
+		RETURN_INT(0);
 
 #ifdef _WIN32
 	DWORD written = 0;
@@ -809,7 +857,7 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 		} else {
 			DEBUG("Previous write not complete");
 			/* Can't take a new write until the previous one finishes. */
-			RETURN_VALUE("0", 0);
+			RETURN_INT(0);
 		}
 	}
 
@@ -818,10 +866,11 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 	if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
 		RETURN_FAIL("SetCommTimeouts() failed");
 
-	/* Keep writing data until the OS has to actually start an async IO for it.
-	 * At that point we know the buffer is full. */
-	while (written < count)
-	{
+	/*
+	 * Keep writing data until the OS has to actually start an async IO
+	 * for it. At that point we know the buffer is full.
+	 */
+	while (written < count) {
 		/* Copy first byte of user buffer. */
 		port->pending_byte = *ptr++;
 
@@ -836,7 +885,7 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 				} else {
 					DEBUG("Asynchronous write running");
 					port->writing = 1;
-					RETURN_VALUE("%d", ++written);
+					RETURN_INT(++written);
 				}
 			} else {
 				/* Actual failure of some kind. */
@@ -850,7 +899,7 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 
 	DEBUG("All bytes written immediately");
 
-	RETURN_VALUE("%d", written);
+	RETURN_INT(written);
 #else
 	/* Returns the number of bytes written, or -1 upon failure. */
 	ssize_t written = write(port->fd, buf, count);
@@ -858,34 +907,38 @@ SP_API enum sp_return sp_nonblocking_write(struct sp_port *port,
 	if (written < 0)
 		RETURN_FAIL("write() failed");
 	else
-		RETURN_VALUE("%d", written);
+		RETURN_INT(written);
 #endif
 }
 
 SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
-                                       size_t count, unsigned int timeout)
+                                       size_t count, unsigned int timeout_ms)
 {
-	TRACE("%p, %p, %d, %d", port, buf, count, timeout);
+	TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
 
 	CHECK_OPEN_PORT();
 
 	if (!buf)
 		RETURN_ERROR(SP_ERR_ARG, "Null buffer");
 
-	if (timeout)
-		DEBUG("Reading %d bytes from port %s, timeout %d ms", count, port->name, timeout);
+	if (timeout_ms)
+		DEBUG_FMT("Reading %d bytes from port %s, timeout %d ms",
+			count, port->name, timeout_ms);
 	else
-		DEBUG("Reading %d bytes from port %s, no timeout", count, port->name);
+		DEBUG_FMT("Reading %d bytes from port %s, no timeout",
+			count, port->name);
 
 	if (count == 0)
-		RETURN_VALUE("0", 0);
+		RETURN_INT(0);
 
 #ifdef _WIN32
 	DWORD bytes_read = 0;
+	DWORD bytes_remaining;
+	int ret;
 
 	/* Set timeout. */
 	port->timeouts.ReadIntervalTimeout = 0;
-	port->timeouts.ReadTotalTimeoutConstant = timeout;
+	port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
 	if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
 		RETURN_FAIL("SetCommTimeouts() failed");
 
@@ -894,7 +947,7 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 		if (GetLastError() == ERROR_IO_PENDING) {
 			DEBUG("Waiting for read to complete");
 			GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE);
-			DEBUG("Read completed, %d/%d bytes read", bytes_read, count);
+			DEBUG_FMT("Read completed, %d/%d bytes read", bytes_read, count);
 		} else {
 			RETURN_FAIL("ReadFile() failed");
 		}
@@ -903,13 +956,18 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 		bytes_read = count;
 	}
 
-	/* Start background operation for subsequent events. */
-	if (WaitCommEvent(port->hdl, &port->events, &port->wait_ovl) == 0) {
-		if (GetLastError() != ERROR_IO_PENDING)
-			RETURN_FAIL("WaitCommEvent() failed");
-	}
+	ret = sp_input_waiting(port);
 
-	RETURN_VALUE("%d", bytes_read);
+	if (ret < 0)
+		RETURN_CODEVAL(ret);
+
+	bytes_remaining = ret;
+
+	/* Restart wait operation if buffer was emptied. */
+	if (bytes_read > 0 && bytes_remaining == 0)
+		TRY(restart_wait(port));
+
+	RETURN_INT(bytes_read);
 
 #else
 	size_t bytes_read = 0;
@@ -918,30 +976,29 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 	fd_set fds;
 	int result;
 
-	if (timeout) {
+	if (timeout_ms) {
 		/* Get time at start of operation. */
 		gettimeofday(&start, NULL);
 		/* Define duration of timeout. */
-		delta.tv_sec = timeout / 1000;
-		delta.tv_usec = (timeout % 1000) * 1000;
+		delta.tv_sec = timeout_ms / 1000;
+		delta.tv_usec = (timeout_ms % 1000) * 1000;
 		/* Calculate time at which we should give up. */
 		timeradd(&start, &delta, &end);
 	}
 
 	/* Loop until we have the requested number of bytes. */
-	while (bytes_read < count)
-	{
+	while (bytes_read < count) {
 		/* Wait until data is available. */
 		FD_ZERO(&fds);
 		FD_SET(port->fd, &fds);
-		if (timeout) {
+		if (timeout_ms) {
 			gettimeofday(&now, NULL);
 			if (timercmp(&now, &end, >))
 				/* Timeout has expired. */
-				RETURN_VALUE("%d", bytes_read);
+				RETURN_INT(bytes_read);
 			timersub(&end, &now, &delta);
 		}
-		result = select(port->fd + 1, &fds, NULL, NULL, timeout ? &delta : NULL);
+		result = select(port->fd + 1, &fds, NULL, NULL, timeout_ms ? &delta : NULL);
 		if (result < 0) {
 			if (errno == EINTR) {
 				DEBUG("select() call was interrupted, repeating");
@@ -950,8 +1007,8 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 				RETURN_FAIL("select() failed");
 			}
 		} else if (result == 0) {
-			DEBUG("read timed out");
-			RETURN_VALUE("%d", bytes_read);
+			DEBUG("Read timed out");
+			RETURN_INT(bytes_read);
 		}
 
 		/* Do read. */
@@ -970,7 +1027,7 @@ SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
 		ptr += result;
 	}
 
-	RETURN_VALUE("%d", bytes_read);
+	RETURN_INT(bytes_read);
 #endif
 }
 
@@ -984,10 +1041,12 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
 	if (!buf)
 		RETURN_ERROR(SP_ERR_ARG, "Null buffer");
 
-	DEBUG("Reading up to %d bytes from port %s", count, port->name);
+	DEBUG_FMT("Reading up to %d bytes from port %s", count, port->name);
 
 #ifdef _WIN32
 	DWORD bytes_read;
+	DWORD bytes_remaining;
+	int ret;
 
 	/* Set timeout. */
 	port->timeouts.ReadIntervalTimeout = MAXDWORD;
@@ -1003,15 +1062,18 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
 	if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
 		RETURN_FAIL("GetOverlappedResult() failed");
 
-	if (bytes_read > 0) {
-		/* Start background operation for subsequent events. */
-		if (WaitCommEvent(port->hdl, &port->events, &port->wait_ovl) == 0) {
-			if (GetLastError() != ERROR_IO_PENDING)
-				RETURN_FAIL("WaitCommEvent() failed");
-		}
-	}
+	ret = sp_input_waiting(port);
 
-	RETURN_VALUE("%d", bytes_read);
+	if (ret < 0)
+		RETURN_CODEVAL(ret);
+
+	bytes_remaining = ret;
+
+	/* Restart wait operation if buffer was emptied. */
+	if (bytes_read > 0 && bytes_remaining == 0)
+		TRY(restart_wait(port));
+
+	RETURN_INT(bytes_read);
 #else
 	ssize_t bytes_read;
 
@@ -1024,7 +1086,7 @@ SP_API enum sp_return sp_nonblocking_read(struct sp_port *port, void *buf,
 			/* This is an actual failure. */
 			RETURN_FAIL("read() failed");
 	}
-	RETURN_VALUE("%d", bytes_read);
+	RETURN_INT(bytes_read);
 #endif
 }
 
@@ -1034,7 +1096,7 @@ SP_API enum sp_return sp_input_waiting(struct sp_port *port)
 
 	CHECK_OPEN_PORT();
 
-	DEBUG("Checking input bytes waiting on port %s", port->name);
+	DEBUG_FMT("Checking input bytes waiting on port %s", port->name);
 
 #ifdef _WIN32
 	DWORD errors;
@@ -1042,12 +1104,12 @@ SP_API enum sp_return sp_input_waiting(struct sp_port *port)
 
 	if (ClearCommError(port->hdl, &errors, &comstat) == 0)
 		RETURN_FAIL("ClearCommError() failed");
-	RETURN_VALUE("%d", comstat.cbInQue);
+	RETURN_INT(comstat.cbInQue);
 #else
 	int bytes_waiting;
 	if (ioctl(port->fd, TIOCINQ, &bytes_waiting) < 0)
 		RETURN_FAIL("TIOCINQ ioctl failed");
-	RETURN_VALUE("%d", bytes_waiting);
+	RETURN_INT(bytes_waiting);
 #endif
 }
 
@@ -1057,7 +1119,7 @@ SP_API enum sp_return sp_output_waiting(struct sp_port *port)
 
 	CHECK_OPEN_PORT();
 
-	DEBUG("Checking output bytes waiting on port %s", port->name);
+	DEBUG_FMT("Checking output bytes waiting on port %s", port->name);
 
 #ifdef _WIN32
 	DWORD errors;
@@ -1065,12 +1127,12 @@ SP_API enum sp_return sp_output_waiting(struct sp_port *port)
 
 	if (ClearCommError(port->hdl, &errors, &comstat) == 0)
 		RETURN_FAIL("ClearCommError() failed");
-	RETURN_VALUE("%d", comstat.cbOutQue);
+	RETURN_INT(comstat.cbOutQue);
 #else
 	int bytes_waiting;
 	if (ioctl(port->fd, TIOCOUTQ, &bytes_waiting) < 0)
 		RETURN_FAIL("TIOCOUTQ ioctl failed");
-	RETURN_VALUE("%d", bytes_waiting);
+	RETURN_INT(bytes_waiting);
 #endif
 }
 
@@ -1105,13 +1167,14 @@ static enum sp_return add_handle(struct sp_event_set *event_set,
 
 	if (!(new_handles = realloc(event_set->handles,
 			sizeof(event_handle) * (event_set->count + 1))))
-		RETURN_ERROR(SP_ERR_MEM, "handle array realloc() failed");
+		RETURN_ERROR(SP_ERR_MEM, "Handle array realloc() failed");
+
+	event_set->handles = new_handles;
 
 	if (!(new_masks = realloc(event_set->masks,
 			sizeof(enum sp_event) * (event_set->count + 1))))
-		RETURN_ERROR(SP_ERR_MEM, "mask array realloc() failed");
+		RETURN_ERROR(SP_ERR_MEM, "Mask array realloc() failed");
 
-	event_set->handles = new_handles;
 	event_set->masks = new_masks;
 
 	((event_handle *) event_set->handles)[event_set->count] = handle;
@@ -1174,22 +1237,22 @@ SP_API void sp_free_event_set(struct sp_event_set *event_set)
 }
 
 SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
-                              unsigned int timeout)
+                              unsigned int timeout_ms)
 {
-	TRACE("%p, %d", event_set, timeout);
+	TRACE("%p, %d", event_set, timeout_ms);
 
 	if (!event_set)
 		RETURN_ERROR(SP_ERR_ARG, "Null event set");
 
 #ifdef _WIN32
 	if (WaitForMultipleObjects(event_set->count, event_set->handles, FALSE,
-			timeout ? timeout : INFINITE) == WAIT_FAILED)
+			timeout_ms ? timeout_ms : INFINITE) == WAIT_FAILED)
 		RETURN_FAIL("WaitForMultipleObjects() failed");
 
 	RETURN_OK();
 #else
 	struct timeval start, delta, now, end = {0, 0};
-	int result, timeout_remaining;
+	int result, timeout_remaining_ms;
 	struct pollfd *pollfds;
 	unsigned int i;
 
@@ -1208,30 +1271,29 @@ SP_API enum sp_return sp_wait(struct sp_event_set *event_set,
 			pollfds[i].events |= POLLERR;
 	}
 
-	if (timeout) {
+	if (timeout_ms) {
 		/* Get time at start of operation. */
 		gettimeofday(&start, NULL);
 		/* Define duration of timeout. */
-		delta.tv_sec = timeout / 1000;
-		delta.tv_usec = (timeout % 1000) * 1000;
+		delta.tv_sec = timeout_ms / 1000;
+		delta.tv_usec = (timeout_ms % 1000) * 1000;
 		/* Calculate time at which we should give up. */
 		timeradd(&start, &delta, &end);
 	}
 
 	/* Loop until an event occurs. */
-	while (1)
-	{
-		if (timeout) {
+	while (1) {
+		if (timeout_ms) {
 			gettimeofday(&now, NULL);
 			if (timercmp(&now, &end, >)) {
-				DEBUG("wait timed out");
+				DEBUG("Wait timed out");
 				break;
 			}
 			timersub(&end, &now, &delta);
-			timeout_remaining = delta.tv_sec * 1000 + delta.tv_usec / 1000;
+			timeout_remaining_ms = delta.tv_sec * 1000 + delta.tv_usec / 1000;
 		}
 
-		result = poll(pollfds, event_set->count, timeout ? timeout_remaining : -1);
+		result = poll(pollfds, event_set->count, timeout_ms ? timeout_remaining_ms : -1);
 
 		if (result < 0) {
 			if (errno == EINTR) {
@@ -1269,7 +1331,7 @@ static enum sp_return get_baudrate(int fd, int *baudrate)
 
 	if (ioctl(fd, get_termios_get_ioctl(), data) < 0) {
 		free(data);
-		RETURN_FAIL("getting termios failed");
+		RETURN_FAIL("Getting termios failed");
 	}
 
 	*baudrate = get_termios_speed(data);
@@ -1292,7 +1354,7 @@ static enum sp_return set_baudrate(int fd, int baudrate)
 
 	if (ioctl(fd, get_termios_get_ioctl(), data) < 0) {
 		free(data);
-		RETURN_FAIL("getting termios failed");
+		RETURN_FAIL("Getting termios failed");
 	}
 
 	DEBUG("Setting baud rate");
@@ -1301,7 +1363,7 @@ static enum sp_return set_baudrate(int fd, int baudrate)
 
 	if (ioctl(fd, get_termios_set_ioctl(), data) < 0) {
 		free(data);
-		RETURN_FAIL("setting termios failed");
+		RETURN_FAIL("Setting termios failed");
 	}
 
 	free(data);
@@ -1324,7 +1386,7 @@ static enum sp_return get_flow(int fd, struct port_data *data)
 
 	if (ioctl(fd, TCGETX, termx) < 0) {
 		free(termx);
-		RETURN_FAIL("getting termiox failed");
+		RETURN_FAIL("Getting termiox failed");
 	}
 
 	get_termiox_flow(termx, &data->rts_flow, &data->cts_flow,
@@ -1348,7 +1410,7 @@ static enum sp_return set_flow(int fd, struct port_data *data)
 
 	if (ioctl(fd, TCGETX, termx) < 0) {
 		free(termx);
-		RETURN_FAIL("getting termiox failed");
+		RETURN_FAIL("Getting termiox failed");
 	}
 
 	DEBUG("Setting advanced flow control");
@@ -1358,7 +1420,7 @@ static enum sp_return set_flow(int fd, struct port_data *data)
 
 	if (ioctl(fd, TCSETX, termx) < 0) {
 		free(termx);
-		RETURN_FAIL("setting termiox failed");
+		RETURN_FAIL("Setting termiox failed");
 	}
 
 	free(termx);
@@ -1374,7 +1436,7 @@ static enum sp_return get_config(struct sp_port *port, struct port_data *data,
 
 	TRACE("%p, %p, %p", port, data, config);
 
-	DEBUG("Getting configuration for port %s", port->name);
+	DEBUG_FMT("Getting configuration for port %s", port->name);
 
 #ifdef _WIN32
 	if (!GetCommState(port->hdl, &data->dcb))
@@ -1591,7 +1653,7 @@ static enum sp_return set_config(struct sp_port *port, struct port_data *data,
 
 	TRACE("%p, %p, %p", port, data, config);
 
-	DEBUG("Setting configuration for port %s", port->name);
+	DEBUG_FMT("Setting configuration for port %s", port->name);
 
 #ifdef _WIN32
 	if (config->baudrate >= 0) {
@@ -1942,8 +2004,10 @@ static enum sp_return set_config(struct sp_port *port, struct port_data *data,
 	if (baud_nonstd != B0) {
 		if (ioctl(port->fd, IOSSIOSPEED, &baud_nonstd) == -1)
 			RETURN_FAIL("IOSSIOSPEED ioctl failed");
-		/* Set baud rates in data->term to correct, but incompatible
-		 * with tcsetattr() value, same as delivered by tcgetattr(). */
+		/*
+		 * Set baud rates in data->term to correct, but incompatible
+		 * with tcsetattr() value, same as delivered by tcgetattr().
+		 */
 		if (cfsetspeed(&data->term, baud_nonstd) < 0)
 			RETURN_FAIL("cfsetspeed() failed");
 	}
@@ -1975,7 +2039,7 @@ SP_API enum sp_return sp_new_config(struct sp_port_config **config_ptr)
 	*config_ptr = NULL;
 
 	if (!(config = malloc(sizeof(struct sp_port_config))))
-		RETURN_ERROR(SP_ERR_MEM, "config malloc failed");
+		RETURN_ERROR(SP_ERR_MEM, "Config malloc failed");
 
 	config->baudrate = -1;
 	config->bits = -1;
@@ -2141,7 +2205,7 @@ SP_API enum sp_return sp_get_signals(struct sp_port *port,
 	if (!signals)
 		RETURN_ERROR(SP_ERR_ARG, "Null result pointer");
 
-	DEBUG("Getting control signals for port %s", port->name);
+	DEBUG_FMT("Getting control signals for port %s", port->name);
 
 	*signals = 0;
 #ifdef _WIN32
@@ -2206,17 +2270,17 @@ SP_API enum sp_return sp_end_break(struct sp_port *port)
 
 SP_API int sp_last_error_code(void)
 {
-	TRACE("");
+	TRACE_VOID();
 #ifdef _WIN32
-	RETURN_VALUE("%d", GetLastError());
+	RETURN_INT(GetLastError());
 #else
-	RETURN_VALUE("%d", errno);
+	RETURN_INT(errno);
 #endif
 }
 
 SP_API char *sp_last_error_message(void)
 {
-	TRACE("");
+	TRACE_VOID();
 
 #ifdef _WIN32
 	LPVOID message;
@@ -2232,9 +2296,9 @@ SP_API char *sp_last_error_message(void)
 		(LPTSTR) &message,
 		0, NULL );
 
-	RETURN_VALUE("%s", message);
+	RETURN_STRING(message);
 #else
-	RETURN_VALUE("%s", strerror(errno));
+	RETURN_STRING(strerror(errno));
 #endif
 }