confdescparser.h

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/* Copyright (C) 2011 Circuits At Home, LTD. All rights reserved.

This software may be distributed and modified under the terms of the GNU
General Public License version 2 (GPL2) as published by the Free Software
Foundation and appearing in the file GPL2.TXT included in the packaging of
this file. Please note that GPL2 Section 2[b] requires that all works based
on this software must also be made publicly available under the terms of
the GPL2 ("Copyleft").

Contact information
-------------------

Circuits At Home, LTD
Web      :  http://www.circuitsathome.com
e-mail   :  support@circuitsathome.com
*/
#if !defined(__CONFDESCPARSER_H__)
#define __CONFDESCPARSER_H__

#include <inttypes.h>

#include <avr/pgmspace.h>
#include "printhex.h"
#include "hexdump.h"
#include "message.h"
#include "parsetools.h"

//#include "hid.h"

class UsbConfigXtracter
{
public:
    //virtual void ConfigXtract(const USB_CONFIGURATION_DESCRIPTOR *conf) = 0;
    //virtual void InterfaceXtract(uint8_t conf, const USB_INTERFACE_DESCRIPTOR *iface) = 0;
    virtual void EndpointXtract(uint8_t conf, uint8_t iface, uint8_t alt, uint8_t proto, const USB_ENDPOINT_DESCRIPTOR *ep) = 0;
};

#define CP_MASK_COMPARE_CLASS           1
#define CP_MASK_COMPARE_SUBCLASS        2
#define CP_MASK_COMPARE_PROTOCOL        4
#define CP_MASK_COMPARE_ALL             7

// Configuration Descriptor Parser Class Template
template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
class ConfigDescParser : public USBReadParser
{
    UsbConfigXtracter       *theXtractor;
    MultiValueBuffer        theBuffer;
    MultiByteValueParser    valParser;
    ByteSkipper             theSkipper;
    uint8_t                 varBuffer[16 /*sizeof(USB_CONFIGURATION_DESCRIPTOR)*/]; 

    uint8_t                 stateParseDescr;    // ParseDescriptor state 

    uint8_t                 dscrLen;            // Descriptor length
    uint8_t                 dscrType;           // Descriptor type

    bool                    isGoodInterface;    // Apropriate interface flag    
    uint8_t                 confValue;          // Configuration value
    uint8_t                 protoValue;         // Protocol value
    uint8_t                 ifaceNumber;        // Interface number
    uint8_t                 ifaceAltSet;        // Interface alternate settings

    bool ParseDescriptor(uint8_t **pp, uint16_t *pcntdn);

    void PrintHidDescriptor(const USB_HID_DESCRIPTOR *pDesc);

public:
    ConfigDescParser(UsbConfigXtracter *xtractor);
    virtual void Parse(const uint16_t len, const uint8_t *pbuf, const uint16_t &offset);
};

template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::ConfigDescParser(UsbConfigXtracter *xtractor) : 
    stateParseDescr(0), 
    dscrLen(0), 
    dscrType(0),
    theXtractor(xtractor)
{
    theBuffer.pValue = varBuffer; 
    valParser.Initialize(&theBuffer);
    theSkipper.Initialize(&theBuffer);
};

template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
void ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::Parse(const uint16_t len, const uint8_t *pbuf, const uint16_t &offset)
{
    uint16_t    cntdn   = (uint16_t)len;
    uint8_t     *p      = (uint8_t*)pbuf; 

    while(cntdn)
        if (!ParseDescriptor(&p, &cntdn))
            return;
}
/* Parser for the configuration descriptor. Takes values for class, subclass, protocol fields in interface descriptor and
  compare masks for them. When the match is found, calls EndpointXtract passing buffer containing endpoint descriptor */
template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
bool ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::ParseDescriptor(uint8_t **pp, uint16_t *pcntdn)
{
    switch (stateParseDescr)
    {
    case 0:
        theBuffer.valueSize = 2;
        valParser.Initialize(&theBuffer);
        stateParseDescr     = 1;
    case 1:
        if (!valParser.Parse(pp, pcntdn))
            return false;
        dscrLen         = *((uint8_t*)theBuffer.pValue); 
        dscrType        = *((uint8_t*)theBuffer.pValue + 1); 
        stateParseDescr = 2;
    case 2:
        // This is a sort of hack. Assuming that two bytes are already in the buffer 
        //  the pointer is positioned two bytes ahead in order for the rest of descriptor 
        //  to be read right after the size and the type fields.
        // This should be used carefuly. varBuffer should be used directly to handle data
        //  in the buffer.
        theBuffer.pValue    = varBuffer + 2;    
        stateParseDescr     = 3;
    case 3:
        switch (dscrType)
        {
        case USB_DESCRIPTOR_INTERFACE:
            isGoodInterface = false;
        case USB_DESCRIPTOR_CONFIGURATION:
            theBuffer.valueSize = sizeof(USB_CONFIGURATION_DESCRIPTOR) - 2;
            break;
        case USB_DESCRIPTOR_ENDPOINT:
            theBuffer.valueSize = sizeof(USB_ENDPOINT_DESCRIPTOR) - 2;
            break;
        case HID_DESCRIPTOR_HID:
            theBuffer.valueSize = dscrLen - 2;
            break;
        }
        valParser.Initialize(&theBuffer);
        stateParseDescr     = 4;
    case 4:
        switch (dscrType)
        {
        case USB_DESCRIPTOR_CONFIGURATION:
            if (!valParser.Parse(pp, pcntdn))
                return false;
            confValue = ((USB_CONFIGURATION_DESCRIPTOR*)varBuffer)->bConfigurationValue;
            break;
        case USB_DESCRIPTOR_INTERFACE:
            if (!valParser.Parse(pp, pcntdn))
                return false;
            if ((MASK & CP_MASK_COMPARE_CLASS) && ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceClass != CLASS_ID)
                break;
            if ((MASK & CP_MASK_COMPARE_SUBCLASS) && ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceSubClass != SUBCLASS_ID)
                break;
            if ((MASK & CP_MASK_COMPARE_PROTOCOL) && ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceProtocol != PROTOCOL_ID)
                break;
            
            isGoodInterface = true;
            ifaceNumber = ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceNumber;
            ifaceAltSet = ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bAlternateSetting;
            protoValue  = ((USB_INTERFACE_DESCRIPTOR*)varBuffer)->bInterfaceProtocol;
            break;
        case USB_DESCRIPTOR_ENDPOINT:
            if (!valParser.Parse(pp, pcntdn))
                return false;
            if (isGoodInterface)
                if (theXtractor)
                    theXtractor->EndpointXtract(confValue, ifaceNumber, ifaceAltSet, protoValue, (USB_ENDPOINT_DESCRIPTOR*)varBuffer);
            break;
        //case HID_DESCRIPTOR_HID:
        //  if (!valParser.Parse(pp, pcntdn))
        //      return false;
        //  PrintHidDescriptor((const USB_HID_DESCRIPTOR*)varBuffer);
        //  break;
        default:
            if (!theSkipper.Skip(pp, pcntdn, dscrLen-2))
                return false;
        }
        theBuffer.pValue = varBuffer; 
        stateParseDescr = 0;
    }
    return true;
}

template <const uint8_t CLASS_ID, const uint8_t SUBCLASS_ID, const uint8_t PROTOCOL_ID, const uint8_t MASK>
void ConfigDescParser<CLASS_ID, SUBCLASS_ID, PROTOCOL_ID, MASK>::PrintHidDescriptor(const USB_HID_DESCRIPTOR *pDesc)
{
    Notify(PSTR("\r\n\r\nHID Descriptor:\r\n"));
    Notify(PSTR("bDescLength:\t\t"));
    PrintHex<uint8_t>(pDesc->bLength);
    
    Notify(PSTR("\r\nbDescriptorType:\t"));
    PrintHex<uint8_t>(pDesc->bDescriptorType);
    
    Notify(PSTR("\r\nbcdHID:\t\t\t"));
    PrintHex<uint16_t>(pDesc->bcdHID);
    
    Notify(PSTR("\r\nbCountryCode:\t\t"));
    PrintHex<uint8_t>(pDesc->bCountryCode);
    
    Notify(PSTR("\r\nbNumDescriptors:\t"));
    PrintHex<uint8_t>(pDesc->bNumDescriptors);
    
    //Notify(PSTR("\r\nbDescrType:\t\t"));
    //PrintHex<uint8_t>(pDesc->bDescrType);
    //
    //Notify(PSTR("\r\nwDescriptorLength:\t"));
    //PrintHex<uint16_t>(pDesc->wDescriptorLength);

    for (uint8_t i=0; i<pDesc->bNumDescriptors; i++)
    {
        HID_CLASS_DESCRIPTOR_LEN_AND_TYPE   *pLT = (HID_CLASS_DESCRIPTOR_LEN_AND_TYPE*)&(pDesc->bDescrType);

        Notify(PSTR("\r\nbDescrType:\t\t"));
        PrintHex<uint8_t>(pLT[i].bDescrType);
        
        Notify(PSTR("\r\nwDescriptorLength:\t"));
        PrintHex<uint16_t>(pLT[i].wDescriptorLength);
    }
    Notify(PSTR("\r\n"));
}


#endif // __CONFDESCPARSER_H__