// -----------------------------------------------------------------------------
// CUpnpHttpSession::ParseRangeHeader
// Parse range values
// -----------------------------------------------------------------------------
//
TBool CUpnpRangeHeaderParser::ParseRangeHeader( TDesC8& aRangeHeader, TInt& aStartPos,
TInt& aEndPos )
{
// Check header's syntax: "bytes=x-y" where y i optional
TInt pos( KErrNotFound );
// 1 string has to contain "="
pos = aRangeHeader.FindC( UpnpString::KEqual() );
if( pos == KErrNotFound )
return EFalse;
// 2 "bytes" has to be at the beginnig
pos = aRangeHeader.FindC( UpnpHTTP::KBytes() );
if( pos == KErrNotFound || pos != 0 )
return EFalse;
// 3 Sets position to after bytes
pos = UpnpHTTP::KBytes().Length();
// 4 If there any space or tab after "bytes" - move pos after it
CUpnpRangeHeaderParser::MovePosition( aRangeHeader, pos );
// 5 "=" - has to be at this position (after "bytes" + spaces or tabs)
if( aRangeHeader[ pos ] != UpnpString::KEqual()[0] )
return EFalse;
// 6 Sets position to after "="
pos++;
// 7 If there any space or tab after "=" - move pos after it
CUpnpRangeHeaderParser::MovePosition( aRangeHeader, pos );
// 8 extract x-y. -1 stands for '=' length
TPtrC8 byteRange = aRangeHeader.Right( aRangeHeader.Length() - pos );
// 9 There can't be any comas because multi-range is not allowed
if( byteRange.Find( UpnpString::KComa() ) != KErrNotFound )
return EFalse;
// 10 "-" delimiter must occure and it cant't be first char, because notation as follows: "-y" is not allowed
pos = byteRange.Find( UpnpString::KMinus() );
if( pos == KErrNotFound )
return EFalse;
// 11 Checks if it is a final bytes request
// e.g. Range: bytes= -20
if( pos == 0 )
{
// If there any space or tab after "-" - move pos after it
CUpnpRangeHeaderParser::MovePosition( byteRange.Right( byteRange.Length()-1 ), pos );
// if pos equal 0 should be 1 to avoid "-" in getting number from string operation
pos = pos == 0 ? 1 : pos;
TLex8 endMinus( byteRange.Right( byteRange.Length() - pos ) );
endMinus.SkipSpace();
TInt error = endMinus.Val( aEndPos );
if ( !CUpnpRangeHeaderParser::HandleConversionException( endMinus, aEndPos, error ) )
{
return EFalse;
}
// We have to check if something else than space or tab leaves after conversion - unless for example 11a will be correct but it is not
if ( CUpnpRangeHeaderParser::HasImproperChars( endMinus ) )
return EFalse;
aStartPos = KErrNotFound;
return ETrue;
}
// 12 All looks fine, so now parse it and get x and y
TLex8 start( byteRange.Left( pos ) );
start.SkipSpace();
// 13 If conversion fails - return error
TInt error = start.Val( aStartPos );
if ( !CUpnpRangeHeaderParser::HandleConversionException( start, aStartPos, error ) )
{
return EFalse;
}
// 14 We have to check if something else than space or tab leaves after conversion - unless for example 11a will be correct but it is not
if ( CUpnpRangeHeaderParser::HasImproperChars( start ) )
return EFalse;
// y is optional
if( ( byteRange.Length() - pos - 1 ) > 0 )
{
TLex8 end( byteRange.Right( byteRange.Length() - pos - 1 ) );
end.SkipSpace();
error = end.Val( aEndPos );
if ( !CUpnpRangeHeaderParser::HandleConversionException( end, aEndPos, error ) )
{
return EFalse;
}
// We have to check if something else than space or tab leaves after conversion - unless for example 11a will be correct but it is not
if ( CUpnpRangeHeaderParser::HasImproperChars( end ) )
return EFalse;
}
else
{
aEndPos = KErrNotFound;
}
return ETrue;
}
