errorCode decodeNBitUnsignedInteger(EXIStream* strm, unsigned char n, unsigned int* int_val)
{
DEBUG_MSG(INFO, DEBUG_STREAM_IO, (">> (%d-bits uint)", n));
if(WITH_COMPRESSION(strm->header.opts.enumOpt) == FALSE && GET_ALIGNMENT(strm->header.opts.enumOpt) == BIT_PACKED)
{
return readBits(strm, n, int_val);
}
else
{
unsigned int byte_number = ((unsigned int) n) / 8 + (n % 8 != 0);
unsigned int tmp_byte_buf = 0;
errorCode tmp_err_code = EXIP_UNEXPECTED_ERROR;
unsigned int i = 0;
*int_val = 0;
for(i = 0; i < byte_number; i++)
{
TRY(readBits(strm, 8, &tmp_byte_buf));
tmp_byte_buf = tmp_byte_buf << (i * 8);
*int_val = *int_val | tmp_byte_buf;
}
}
return EXIP_OK;
}
errorCode decodeHeader(EXIStream* strm, boolean outOfBandOpts)
{
errorCode tmp_err_code = UNEXPECTED_ERROR;
unsigned int bits_val = 0;
boolean boolVal = FALSE;
DEBUG_MSG(INFO, DEBUG_CONTENT_IO, (">Start EXI header decoding\n"));
TRY(readBits(strm, 2, &bits_val));
if(bits_val == 2) // The header Distinguishing Bits i.e. no EXI Cookie
{
strm->header.has_cookie = 0;
DEBUG_MSG(INFO, DEBUG_CONTENT_IO, (">No EXI cookie detected\n"));
}
else if(bits_val == 0)// ASCII code for $ = 00100100 (36)
{
TRY(readBits(strm, 6, &bits_val));
if(bits_val != 36)
return INVALID_EXI_HEADER;
TRY(readBits(strm, 8, &bits_val));
if(bits_val != 69) // ASCII code for E = 01000101 (69)
return INVALID_EXI_HEADER;
TRY(readBits(strm, 8, &bits_val));
if(bits_val != 88) // ASCII code for X = 01011000 (88)
return INVALID_EXI_HEADER;
TRY(readBits(strm, 8, &bits_val));
if(bits_val != 73) // ASCII code for I = 01001001 (73)
return INVALID_EXI_HEADER;
strm->header.has_cookie = 1;
DEBUG_MSG(INFO, DEBUG_CONTENT_IO, (">EXI cookie detected\n"));
TRY(readBits(strm, 2, &bits_val));
if(bits_val != 2) // The header Distinguishing Bits are required
return INVALID_EXI_HEADER;
}
else
{
return INVALID_EXI_HEADER;
}
// Read the Presence Bit for EXI Options
TRY(readNextBit(strm, &boolVal));
if(boolVal == TRUE) // There are EXI options
{
strm->header.has_options = TRUE;
// validation checks. If the options are included then
// they cannot be set by an out-of-band mechanism.
// If out-of-band options are set -
// rise a warning and overwrite them.
// Only the options from the header will be used
if(outOfBandOpts == TRUE)
{
DEBUG_MSG(WARNING, DEBUG_CONTENT_IO, (">Ignored out-of-band set EXI options\n"));
makeDefaultOpts(&strm->header.opts);
}
}
else // Out-of-band set EXI options
{
DEBUG_MSG(INFO, DEBUG_CONTENT_IO, (">No EXI options field in the header\n"));
strm->header.has_options = FALSE;
if(outOfBandOpts == FALSE)
{
DEBUG_MSG(ERROR, DEBUG_CONTENT_IO, (">No EXI options in the header and no out-of-band options specified. \n"));
return HEADER_OPTIONS_MISMATCH;
}
}
// Read the Version type
TRY(readNextBit(strm, &boolVal));
strm->header.is_preview_version = boolVal;
strm->header.version_number = 1;
do
{
TRY(readBits(strm, 4, &bits_val));
strm->header.version_number += bits_val;
if(bits_val < 15)
break;
} while(1);
DEBUG_MSG(INFO, DEBUG_CONTENT_IO, (">EXI version: %d\n", strm->header.version_number));
if(strm->header.has_options == 1)
{
Parser optionsParser;
struct ops_AppData appD;
TRY(initParser(&optionsParser, strm->buffer, &appD));
optionsParser.strm.context.bitPointer = strm->context.bitPointer;
optionsParser.strm.context.bufferIndx = strm->context.bufferIndx;
optionsParser.strm.gStack = NULL;
makeDefaultOpts(&optionsParser.strm.header.opts);
SET_STRICT(optionsParser.strm.header.opts.enumOpt);
optionsParser.handler.fatalError = ops_fatalError;
optionsParser.handler.error = ops_fatalError;
optionsParser.handler.startDocument = ops_startDocument;
optionsParser.handler.endDocument = ops_endDocument;
optionsParser.handler.startElement = ops_startElement;
optionsParser.handler.attribute = ops_attribute;
optionsParser.handler.stringData = ops_stringData;
optionsParser.handler.endElement = ops_endElement;
optionsParser.handler.intData = ops_intData;
optionsParser.handler.booleanData = ops_boolData;
appD.o_strm = &optionsParser.strm;
appD.parsed_ops = &strm->header.opts;
appD.prevElementLnID = 0;
appD.prevElementUriID = 0;
appD.permanentAllocList = &strm->memList;
TRY_CATCH(setSchema(&optionsParser, (EXIPSchema*) &ops_schema), destroyParser(&optionsParser));
TRY_CATCH(createValueTable(&optionsParser.strm.valueTable), destroyParser(&optionsParser));
while(tmp_err_code == ERR_OK)
{
tmp_err_code = parseNext(&optionsParser);
}
destroyParser(&optionsParser);
if(tmp_err_code != PARSING_COMPLETE)
return tmp_err_code;
strm->buffer.bufContent = optionsParser.strm.buffer.bufContent;
strm->context.bitPointer = optionsParser.strm.context.bitPointer;
strm->context.bufferIndx = optionsParser.strm.context.bufferIndx;
if(WITH_COMPRESSION(strm->header.opts.enumOpt) ||
GET_ALIGNMENT(strm->header.opts.enumOpt) != BIT_PACKED)
{
// Padding bits
if(strm->context.bitPointer != 0)
{
strm->context.bitPointer = 0;
strm->context.bufferIndx += 1;
}
}
}
return checkOptionValues(&strm->header.opts);
}
