CInterfaceFTDI.h

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2018, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */
#pragma once

#include <mrpt/config.h>
#include <mrpt/io/CStream.h>
#include <mrpt/containers/circular_buffer.h>

#include <deque>

namespace mrpt::comms
{
/** A list of FTDI devices and their descriptors.
 * \sa CInterfaceFTDI::ListAllDevices
 * \ingroup mrpt_comms_grp
 */
struct TFTDIDevice
{
    std::string ftdi_manufacturer;
    std::string ftdi_description;
    std::string ftdi_serial;

    uint16_t usb_idVendor;
    uint16_t usb_idProduct;
    uint8_t usb_serialNumber;

#if defined(MRPT_OS_LINUX) || defined(__APPLE__)
    /** Only for Linux: the corresponding libusb's `libusb_device*` (or
     * `usb_device*` for libftdi <1.2) */
    void* usb_device_struct;
#endif
};

/** Print out all the information of a FTDI device in textual form. */
std::ostream& operator<<(std::ostream& o, const TFTDIDevice& d);

/** Used in  CInterfaceFTDI::ListAllDevices */
using TFTDIDeviceList = std::deque<TFTDIDevice>;

/** A definition of a CStream actually representing a USB connection to a FTDI
 *chip.
 *
 *  This class implements the communication with FT245BM / FT245RL chips.
 *   Using this class makes a program to depend on:
 *      - Windows: "FT2XX.DLL" and the device drivers (see FTDI website).
 *      - Linux: "libusb.so" (quite standard!), and "libftdi.so" only if linking
 *against the dynamic library.
 *
 *  If there is any error during the communications (or loading the Windows
 *DLL), a std::exception will be raised.
 *
 *  To write bulk data, use CStream::ReadBuffer and CStream::WriteBuffer.
 *
 * Warning: Avoid defining an object of this class in a global scope if you want
 *to catch all potential
 *      exceptions during the constructors (like DLL not found, etc...)
 *
 * VERSIONS:
 *      - 11/APR/2005: Initial development. JLBC
 *      - 16/FEB/2007: Integration into the MRPT framework. Support for device
 *serial numbers. JLBC
 *      - 15/APR/2008: Implemented for Linux using libftdi. JLBC
 *
 * \sa CStream
 * \ingroup mrpt_comms_grp
 */
class CInterfaceFTDI : public mrpt::io::CStream
{
   public:
    /** Constructor, which loads driver interface (the DLL under Windows).
     */
    CInterfaceFTDI();

    /** Destructor, which closes the connection with the chip and unloads the
     * driver interface.
     */
    virtual ~CInterfaceFTDI();

    /** This object cannot be copied */
    CInterfaceFTDI(const CInterfaceFTDI& o) = delete;

    /** This object cannot be copied */
    CInterfaceFTDI& operator=(const CInterfaceFTDI& o) = delete;

    /** Checks whether the chip has been successfully open.
     * \sa OpenBySerialNumber, OpenByDescription
     */
    bool isOpen();

    /** Open by device serial number
     */
    void OpenBySerialNumber(const std::string& serialNumber);

    /** Open by device description
     */
    void OpenByDescription(const std::string& description);

    /** Close the USB device */
    void Close();

    /** Reset the USB device */
    void ResetDevice();

    /** Purge the I/O buffers */
    void Purge();

    /** Change the latency timer (in milliseconds) implemented on the FTDI chip:
     * for a few ms, data is not sent to the PC waiting for possible more data,
     * to save USB trafic. */
    void SetLatencyTimer(unsigned char latency_ms);

    /** Change read & write timeouts, in milliseconds. */
    void SetTimeouts(
        unsigned long dwReadTimeout_ms, unsigned long dwWriteTimeout_ms);

    /** Generates a list with all FTDI devices connected right now.
     */
    void ListAllDevices(TFTDIDeviceList& outList);

    /** Tries to read, raising no exception if not all the bytes are available,
     * but raising one if there is some communication error.
     */
    size_t ReadSync(void* Buffer, size_t Count) { return Read(Buffer, Count); }
    /** Tries to write, raising no exception if not all the bytes are available,
     * but raising one if there is some communication error.
     */
    size_t WriteSync(const void* Buffer, size_t Count)
    {
        return Write(Buffer, Count);
    }

    /** Reads a block of bytes from the stream into Buffer, and returns the
     *amound of bytes actually read, without waiting for more extra bytes to
     *arrive (just those already enqued in the stream).
     *  In this class this method actually behaves as expected and does not
     *fallback to ReadBuffer().
     *  \exception std::exception On any error, or if ZERO bytes are read.
     */
    virtual size_t ReadBufferImmediate(void* Buffer, size_t Count);

    /** Introduces a pure virtual method responsible for reading from the
     * stream.
     *  It integrates a cache buffer to speed-up sequences of many, small
     * readings.
     */
    size_t Read(void* Buffer, size_t Count);

    /** Introduces a pure virtual method responsible for writing to the stream.
     *  Write attempts to write up to Count bytes to Buffer, and returns the
     * number of bytes actually written.
     */
    size_t Write(const void* Buffer, size_t Count);

    /** This virtual method does nothing in this class.
     */
    uint64_t Seek(int64_t Offset, CStream::TSeekOrigin Origin = sFromBeginning);

    /** This virtual method does nothing in this class.
     */
    uint64_t getTotalBytesCount() const;

    /** This virtual method does nothing in this class.
     */
    uint64_t getPosition() const;

   protected:
    /** Used in Read */
    mrpt::containers::circular_buffer<uint8_t> m_readBuffer;

    void ftdi_read(
        void* lpvBuffer, unsigned long dwBuffSize,
        unsigned long* lpdwBytesRead);
    void ftdi_write(
        const void* lpvBuffer, unsigned long dwBuffSize,
        unsigned long* lpdwBytes);

#if defined(_WIN32)
   private:
    void checkErrorAndRaise(int errorCode);

    void ftdi_open(void* pvDevice);
    void ftdi_openEx(void* pArg1, unsigned long dwFlags);
    void ftdi_listDevices(void* pArg1, void* pArg2, unsigned long dwFlags);
    void ftdi_getQueueStatus(unsigned long* lpdwAmountInRxQueue);

    void* m_hmodule;
    unsigned long m_ftHandle;

    void loadDriver();

    enum FT_STATUS{dummy};

    typedef FT_STATUS(__stdcall* PtrToOpen)(void*, unsigned long*);
    PtrToOpen m_pOpen;

    typedef FT_STATUS(__stdcall* PtrToOpenEx)(
        void*, unsigned long, unsigned long*);
    PtrToOpenEx m_pOpenEx;

    typedef FT_STATUS(__stdcall* PtrToListDevices)(void*, void*, unsigned long);
    PtrToListDevices m_pListDevices;

    typedef FT_STATUS(__stdcall* PtrToClose)(unsigned long);
    PtrToClose m_pClose;

    typedef FT_STATUS(__stdcall* PtrToRead)(
        unsigned long, void*, unsigned long, unsigned long*);
    PtrToRead m_pRead;

    typedef FT_STATUS(__stdcall* PtrToWrite)(
        unsigned long, const void*, unsigned long, unsigned long*);
    PtrToWrite m_pWrite;

    typedef FT_STATUS(__stdcall* PtrToResetDevice)(unsigned long);
    PtrToResetDevice m_pResetDevice;

    typedef FT_STATUS(__stdcall* PtrToPurge)(unsigned long, unsigned long);
    PtrToPurge m_pPurge;

    typedef FT_STATUS(__stdcall* PtrToSetTimeouts)(
        unsigned long, unsigned long, unsigned long);
    PtrToSetTimeouts m_pSetTimeouts;

    typedef FT_STATUS(__stdcall* PtrToGetQueueStatus)(
        unsigned long, unsigned long*);
    PtrToGetQueueStatus m_pGetQueueStatus;

    typedef FT_STATUS(__stdcall* PtrToSetLatencyTimer)(
        unsigned long, unsigned char);
    PtrToSetLatencyTimer m_pSetLatencyTimer;

#else
    // Declarations for Linux:
    void* m_ftdi_context;

    /** Process recursively a USB device and its children: */
    void recursive_fill_list_devices(
        void* usb_device_structure, TFTDIDeviceList& outList);

#endif

};  // end of class

}