perplex.cpp

著名的 helix realplayer 基于手机 symbian 系统的 播放器全套源代码

{
	if (n<m_nSize)
		return(TRUE);
	else return(FALSE);
}


//*******************************************************************
//*************** CHXPerplexBuffer::EnsureValidOffset() *************
//*******************************************************************

// make sure that pPos is in the buffer.
// If not, the buffer is automatically resized and contents copied.
// pPos must be > pData.

BOOL CHXPerplexBuffer::EnsureValidOffset(UINT32 n)
{
    if (IsValidOffset(n)==TRUE)
    {
	return(TRUE);
    }

    return (this->Resize(n));
}


//*******************************************************************
//********************* CHXPerplexBuffer::Resize() ******************
//*******************************************************************

BOOL CHXPerplexBuffer::Resize(UINT32 nNewSize)
{
    if (nNewSize==0)
    {
	Free();
	return(TRUE);
    }

    nNewSize = RoundUpToGrowSize(nNewSize);

    UCHAR*	pNewBuffer = new UCHAR[nNewSize];
    if (pNewBuffer==NULL) return(FALSE);


    if (m_pData!=NULL)
    {
	// copy MIN(oldSize,newSize) elements
	memcpy(pNewBuffer,m_pData, (nNewSize<m_nSize) ? (int)nNewSize : (int)m_nSize); /* Flawfinder: ignore */
	delete [] m_pData;
    }

    m_pData = pNewBuffer;
    m_nSize = nNewSize;

    return(TRUE);
}

//*******************************************************************
//**************** CHXPerplexBuffer::RoundUpToGrowSize() ************
//*******************************************************************

UINT32 CHXPerplexBuffer::RoundUpToGrowSize(UINT32 nSize)
{
    // check for div-by-zero errors (as long as DEFAULT!=0)
    if (m_nGrowBy==0)
    {
	m_nGrowBy = DEFAULT_GROW_SIZE;
    }

    return ( (int)(nSize/m_nGrowBy)+1 ) * m_nGrowBy;
}

//*******************************************************************
//****************** CHXPerplexBuffer::SafeMemCopy() ****************
//*******************************************************************

// copy data into the buffer at the given offset, and if the buffer
// is too small we'll resize the buffer first.

BOOL CHXPerplexBuffer::SafeMemCopy(UINT32 nOffset, const void* data, UINT32 len)
{
    if (EnsureValidOffset(nOffset+len-1)==TRUE)
    {
    	memcpy( m_pData+nOffset, data, (int)len ); /* Flawfinder: ignore */
	return(TRUE);
    }
    return(FALSE);
}



//*******************************************************************
//********************** CHXPerplexBuffer::Free() *******************
//*******************************************************************

void CHXPerplexBuffer::Free()
{
    if (m_pData!=NULL)
    delete [] m_pData;

    m_pData=NULL;
    m_nSize=0;
}

//*******************************************************************
//************************** FourByteAlign **************************
//*******************************************************************
/*  already in pnmisc.lib
UINT16 	FourByteAlign(UINT16 number)
{
	return( ((number+3)>>2)<<2 );
}
*/

//*******************************************************************
//************************ MapFromMIMEBase64 ************************
//*******************************************************************

//  Converts appropriate characters for MIME-Base64 encoding into a the
//  Base64 ordinal.

// A copy of this is kept in in pnmisc\pub\win\pnmisc16.h.  If you change 
// this (which is very unlikely), then be sure to change it there.  
static const char zMIMEBase64Chars[] =
	{
	'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
	'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
	'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
	'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
	'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
	'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
	'8', '9', '+', '/'
	};						

#define MIME_BASE64_PADDING		'='
#define FROM_MIME_BASE64_BYTES_IN	4
#define FROM_MIME_BASE64_BYTES_OUT	3
#define TO_MIME_BASE64_BYTES_IN		FROM_MIME_BASE64_BYTES_OUT
#define TO_MIME_BASE64_BYTES_OUT	FROM_MIME_BASE64_BYTES_IN

UCHAR CHXPerplex::MapFromMIMEBase64(char MIMEBase64)
{
    for (UCHAR n = 0; n < sizeof(zMIMEBase64Chars)/sizeof(zMIMEBase64Chars[0]); n++)
    {
	if (MIMEBase64 == zMIMEBase64Chars[n])
	{
	    return n;
	}
    }
    HX_ASSERT(FALSE);
    return 0;
}

//*******************************************************************
//************************ MapFromMIMEBase64 ************************
//*******************************************************************

// Converts a digit ordinal to the MIMEBase64 digit...

char CHXPerplex::MapToMIMEBase64(UCHAR MIMEBase64)
{
    HX_ASSERT(MIMEBase64 < sizeof(zMIMEBase64Chars)/sizeof(zMIMEBase64Chars[0]));
    return zMIMEBase64Chars[MIMEBase64];
}

//*******************************************************************
//************************ SetFromMIMEBase64 ************************
//*******************************************************************

//	Return:	int	Size in bytes of decoded information

UINT32 CHXPerplex::SetFromMIMEBase64(const char* MIMEBase64, char* Bits, UINT32 nSize)
{
    UINT32	ndxBits		= 0;
    UINT32	ndxMIMEBase64	= 0;
    BOOL	bDone		= FALSE;
    UINT32	ndxTempIn	= 0;
    UCHAR	tempBitsIn[FROM_MIME_BASE64_BYTES_IN];
    UINT32	padding		= 0;

    HX_ASSERT(strlen(MIMEBase64) <= nSize);

    while (!bDone)
    {
	HX_ASSERT(ndxMIMEBase64 <= nSize);
	HX_ASSERT(ndxBits <= nSize);

	// Fill in our "temporary" in buffer with the Base64 characters.
	for (ndxTempIn = 0;
	     ndxTempIn < FROM_MIME_BASE64_BYTES_IN && (padding == 0);
	     ndxTempIn++)
	{
	    HX_ASSERT(ndxMIMEBase64 <= nSize);
	    UCHAR MIMEBase64char = MIMEBase64[ndxMIMEBase64];

	    switch (MIMEBase64char)
	    {
		case MIME_BASE64_PADDING:
		case '\0':
		{
		    tempBitsIn[ndxTempIn] = 0;
		    bDone = TRUE;
		    padding = (FROM_MIME_BASE64_BYTES_IN - ndxTempIn);
		}
		break;

		default:
		{
		    tempBitsIn[ndxTempIn] = MapFromMIMEBase64(MIMEBase64char);
		}
		break;
	    }
	    ndxMIMEBase64++;
	}

	HX_ASSERT(padding == 2 || padding == 1 || padding == 0);

	// Map the Base64 in buffer to the the output buffer...
	// This should map the 6 pertinate bits of each IN byte, to the
	// the correct bits of the OUT byte.
	{
	    Bits[ndxBits] = (tempBitsIn[0] << 2) + (tempBitsIn[1]>>4);
	    ndxBits++;

	    if (padding < 2)
	    {
		Bits[ndxBits] = (tempBitsIn[1] << 4) + (tempBitsIn[2]>>2);
		ndxBits++;
	    }

	    if (padding < 1)
	    {
		Bits[ndxBits] = (tempBitsIn[2] << 6) + (tempBitsIn[3]);
		ndxBits++;
	    }
	}
    }

    Bits[ndxBits] = '\0';
    return ndxBits;
}

//*******************************************************************
//************************ DumpToMIMEBase64 *************************
//*******************************************************************

void CHXPerplex::DumpToMIMEBase64(char* MIMEBase64, const char* Bits, UINT32 nSize)
{
    UINT32	ndxBits			= 0;
    UINT32	ndxMIMEBase64	= 0;
    BOOL			bDone			= FALSE;
    UINT32	ndxTempIn		= 0;
    UINT32	ndxTempOut		= 0;
    UCHAR			tempBitsIn [FROM_MIME_BASE64_BYTES_IN];
    UINT32	padding			= 0;

    HX_ASSERT(strlen(Bits) <= nSize);

    while (!bDone)
    {
	HX_ASSERT(ndxMIMEBase64 <= nSize);
	HX_ASSERT(ndxBits <= nSize);

	// Fill in our "temporary" out buffer with the 6 bit chunks of the input.
	for (	ndxTempIn = 0;
		ndxTempIn < TO_MIME_BASE64_BYTES_IN && (padding == 0);
		ndxTempIn++)
	{
	    UCHAR rawChar = Bits[ndxBits];

	    if (rawChar != '\0')
	    {
		switch (ndxTempIn)
		{
		    case 0:
		    {
			tempBitsIn[0] = rawChar >> 2;
			tempBitsIn[1] = (rawChar & 0x3) << 4;
		    }
		    break;

		    case 1:
		    {
			tempBitsIn[1] += rawChar >> 4;
			tempBitsIn[2] = (rawChar & 0xF) << 2;
		    }
		    break;

		    case 2:
		    {
			tempBitsIn[2] += rawChar >> 6;
			tempBitsIn[3] = (rawChar & 0x3F);
		    }
		    break;
		}
	    }
	    else
	    {
		bDone = TRUE;
		padding = (TO_MIME_BASE64_BYTES_IN - ndxTempIn);
	    }
	    ndxBits++;
	}

	HX_ASSERT(padding == 2 || padding == 1 || padding == 0);

	// Map the Base64 in buffer to the output buffer...
	// This should map the 6 pertinate bits of each IN byte, as an
	// entire OUT byte
	for (	ndxTempOut = 0;
		ndxTempOut < TO_MIME_BASE64_BYTES_OUT;
		ndxTempOut++)
	{
	    if (ndxTempOut < (TO_MIME_BASE64_BYTES_OUT-padding))
	    {
		MIMEBase64[ndxMIMEBase64] = MapToMIMEBase64(tempBitsIn[ndxTempOut]);
	    }
	    else
	    {
		MIMEBase64[ndxMIMEBase64] = MIME_BASE64_PADDING;
	    }
	    ndxMIMEBase64++;
	}
    }
    MIMEBase64[ndxMIMEBase64] = '\0';
}