Method write

external/floppybridge/src/SerialIO.cpp:799–856

Attempts to write some data to the port. Returns how much it actually wrote. If writeAll is not TRUE then it will write what it can until it times out

// Attempts to write some data to the port.  Returns how much it actually wrote.
// If writeAll is not TRUE then it will write what it can until it times out
unsigned int SerialIO::write(const void* data, unsigned int dataLength) {
	if ((data == nullptr) || (dataLength == 0)) return 0;
	if (!isPortOpen()) return 0;

#ifdef FTDI_D2XX_AVAILABLE
	if (m_ftdi.isOpen()) {
		m_ftdi.FT_SetTimeouts(m_readTimeout + (m_readTimeoutMultiplier * dataLength), m_writeTimeout + (m_writeTimeoutMultiplier * dataLength));

		DWORD written = 0;
		if (m_ftdi.FT_Write((LPVOID)data, dataLength, &written) != FTDI::FT_STATUS::FT_OK) written = 0;
		return written;
	}
#endif

#ifdef _WIN32
	DWORD written = 0;
	if (!WriteFile(m_portHandle, data, dataLength, &written, NULL)) written = 0;
	return written;
#else
	unsigned int totalTime = m_writeTimeout + (m_writeTimeoutMultiplier * dataLength);

	struct timeval timeout;
	timeout.tv_sec = totalTime / 1000;
	timeout.tv_usec = (totalTime - (timeout.tv_sec * 1000)) * 1000;

	size_t written = 0;
	unsigned char* buffer = (unsigned char*)data;

	fd_set fds;

	FD_ZERO(&fds);
	FD_SET(m_portHandle, &fds);

	// Write with a timeout
	while (written < dataLength) {
		if ((timeout.tv_sec < 1) && (timeout.tv_usec < 1)) break;

		int result = select(m_portHandle + 1, NULL, &fds, NULL, &timeout);
		if (result < 0) {
			if (errno == EINTR || errno == EAGAIN) continue; else return 0;
		}
		else if (result == 0) break;

		result = ::write(m_portHandle, buffer, dataLength - written);

		if (result < 0) {
			if (errno == EINTR || errno == EAGAIN) continue; else return 0;
		}

		written += result;
		buffer += result;
	}

	return written;
#endif

	return 0;
}