EbmlElement *EbmlParser::Get( int n_call )
{
int i_ulev = 0;
EbmlElement *p_prev = NULL;
if( mi_user_level != mi_level )
{
return NULL;
}
if( m_got )
{
EbmlElement *ret = m_got;
m_got = NULL;
return ret;
}
p_prev = m_el[mi_level];
if( m_el[mi_level] )
{
m_el[mi_level]->SkipData( *m_es, EBML_CONTEXT(m_el[mi_level]) );
}
/* Ignore unknown level 0 or 1 elements */
m_el[mi_level] = m_es->FindNextElement( EBML_CONTEXT(m_el[mi_level - 1]),
i_ulev, UINT64_MAX,
( mb_dummy | (mi_level > 1) ), 1 );
if( i_ulev > 0 )
{
if( p_prev )
{
if( !mb_keep )
{
if( MKV_IS_ID( p_prev, KaxBlockVirtual ) )
static_cast<KaxBlockVirtualWorkaround*>(p_prev)->Fix();
delete p_prev;
}
mb_keep = false;
}
while( i_ulev > 0 )
{
if( mi_level == 1 )
{
mi_level = 0;
return NULL;
}
delete m_el[mi_level - 1];
m_got = m_el[mi_level -1] = m_el[mi_level];
m_el[mi_level] = NULL;
mi_level--;
i_ulev--;
}
return NULL;
}
else if( m_el[mi_level] == NULL )
{
msg_Warn( p_demux,"MKV/Ebml Parser: m_el[mi_level] == NULL\n" );
}
else if( m_el[mi_level]->IsDummy() && !mb_dummy )
{
bool b_bad_position = false;
/* We got a dummy element but don't want those...
* perform a sanity check */
if( !mi_level )
{
msg_Err(p_demux, "Got invalid lvl 0 element... Aborting");
return NULL;
}
if( p_prev && p_prev->IsFiniteSize() &&
p_prev->GetEndPosition() != m_el[mi_level]->GetElementPosition() &&
mi_level > 1 )
{
msg_Err( p_demux, "Dummy Element at unexpected position... corrupted file?" );
b_bad_position = true;
}
if( n_call < 10 && !b_bad_position && m_el[mi_level]->IsFiniteSize() &&
( !m_el[mi_level-1]->IsFiniteSize() ||
m_el[mi_level]->GetEndPosition() <= m_el[mi_level-1]->GetEndPosition() ) )
{
/* The element fits inside its upper element */
msg_Warn( p_demux, "Dummy element found %"PRIu64"... skipping it",
m_el[mi_level]->GetElementPosition() );
return Get( ++n_call );
}
else
{
/* Too large, misplaced or 10 successive dummy elements */
msg_Err( p_demux,
"Dummy element too large or misplaced at %"PRIu64"... skipping to next upper element",
m_el[mi_level]->GetElementPosition() );
if( mi_level >= 1 &&
m_el[mi_level]->GetElementPosition() >= m_el[mi_level-1]->GetEndPosition() )
{
msg_Err(p_demux, "This element is outside its known parent... upping level");
delete m_el[mi_level - 1];
m_got = m_el[mi_level -1] = m_el[mi_level];
m_el[mi_level] = NULL;
mi_level--;
return NULL;
}
delete m_el[mi_level];
m_el[mi_level] = NULL;
m_el[mi_level - 1]->SkipData( *m_es, EBML_CONTEXT(m_el[mi_level - 1]) );
return Get();
}
}
if( p_prev )
{
if( !mb_keep )
{
if( MKV_IS_ID( p_prev, KaxBlockVirtual ) )
static_cast<KaxBlockVirtualWorkaround*>(p_prev)->Fix();
delete p_prev;
}
mb_keep = false;
}
return m_el[mi_level];
}
EbmlElement *EbmlParser::Get( int n_call )
{
int i_ulev = 0;
EbmlElement *p_prev = NULL;
if( mi_user_level != mi_level )
{
return NULL;
}
if( m_got )
{
EbmlElement *ret = m_got;
m_got = NULL;
return ret;
}
p_prev = m_el[mi_level];
if( m_el[mi_level] )
{
m_el[mi_level]->SkipData( *m_es, EBML_CONTEXT(m_el[mi_level]) );
}
// If the parent is a segment, use the segment context when creating children
// (to prolong their lifetime), otherwise just continue as normal
EbmlSemanticContext e_context =
EBML_CTX_MASTER( EBML_CONTEXT(m_el[mi_level - 1]) ) == EBML_CTX_MASTER( Context_KaxSegmentVLC )
? Context_KaxSegmentVLC
: EBML_CONTEXT(m_el[mi_level - 1]);
/* Ignore unknown level 0 or 1 elements */
m_el[mi_level] = m_es->FindNextElement( e_context,
i_ulev, UINT64_MAX,
( mb_dummy | (mi_level > 1) ), 1 );
if( i_ulev > 0 )
{
if( p_prev )
{
if( !mb_keep )
{
if( MKV_IS_ID( p_prev, KaxBlockVirtual ) )
static_cast<KaxBlockVirtualWorkaround*>(p_prev)->Fix(); // !! WARNING : TODO !! this is undefined-behavior
delete p_prev;
}
mb_keep = false;
}
while( i_ulev > 0 )
{
if( mi_level == 1 )
{
mi_level = 0;
return NULL;
}
delete m_el[mi_level - 1];
m_got = m_el[mi_level -1] = m_el[mi_level];
m_el[mi_level] = NULL;
mi_level--;
i_ulev--;
}
return NULL;
}
else if( m_el[mi_level] == NULL )
{
msg_Dbg( p_demux,"MKV/Ebml Parser: m_el[mi_level] == NULL" );
}
else if( m_el[mi_level]->IsDummy() && !mb_dummy )
{
bool b_bad_position = false;
/* We got a dummy element but don't want those...
* perform a sanity check */
if( !mi_level )
{
msg_Err(p_demux, "Got invalid lvl 0 element... Aborting");
return NULL;
}
if( p_prev && p_prev->IsFiniteSize() &&
p_prev->GetEndPosition() != m_el[mi_level]->GetElementPosition() &&
mi_level > 1 )
{
msg_Err( p_demux, "Dummy Element at unexpected position... corrupted file?" );
b_bad_position = true;
}
if( n_call < M_EL_MAXSIZE && !b_bad_position && m_el[mi_level]->IsFiniteSize() &&
( !m_el[mi_level-1]->IsFiniteSize() ||
m_el[mi_level]->GetEndPosition() <= m_el[mi_level-1]->GetEndPosition() ) )
{
/* The element fits inside its upper element */
msg_Warn( p_demux, "Dummy element found %" PRIu64 "... skipping it",
m_el[mi_level]->GetElementPosition() );
return Get( ++n_call );
}
else
{
/* Too large, misplaced or M_EL_MAXSIZE successive dummy elements */
msg_Err( p_demux,
"Dummy element too large or misplaced at %" PRIu64 "... skipping to next upper element",
m_el[mi_level]->GetElementPosition() );
if( mi_level >= 1 &&
m_el[mi_level]->GetElementPosition() >= m_el[mi_level-1]->GetEndPosition() )
{
msg_Err(p_demux, "This element is outside its known parent... upping level");
delete m_el[mi_level - 1];
m_got = m_el[mi_level -1] = m_el[mi_level];
m_el[mi_level] = NULL;
mi_level--;
return NULL;
}
delete m_el[mi_level];
delete p_prev;
m_el[mi_level] = NULL;
m_el[mi_level - 1]->SkipData( *m_es, EBML_CONTEXT(m_el[mi_level - 1]) );
return Get();
}
}
if( p_prev )
{
if( !mb_keep )
{
if( MKV_IS_ID( p_prev, KaxBlockVirtual ) )
static_cast<KaxBlockVirtualWorkaround*>(p_prev)->Fix();
delete p_prev;
}
mb_keep = false;
}
return m_el[mi_level];
}
/*!
\brief Method to help reading a Master element and all subsequent children quickly
\todo add an option to discard even unknown elements
\todo handle when a mandatory element is not found
*/
void EbmlMaster::Read(EbmlStream & inDataStream, const EbmlSemanticContext & sContext, int & UpperEltFound, EbmlElement * & FoundElt, bool AllowDummyElt, ScopeMode ReadFully)
{
if (ReadFully != SCOPE_NO_DATA)
{
EbmlElement * ElementLevelA;
// remove all existing elements, including the mandatory ones...
size_t Index;
for (Index=0; Index<ElementList.size(); Index++) {
if (!(*ElementList[Index]).IsLocked()) {
delete ElementList[Index];
}
}
ElementList.clear();
uint64 MaxSizeToRead;
if (IsFiniteSize())
MaxSizeToRead = GetSize();
else
MaxSizeToRead = 0x7FFFFFFF;
// read blocks and discard the ones we don't care about
if (MaxSizeToRead > 0)
{
inDataStream.I_O().setFilePointer(GetSizePosition() + GetSizeLength(), seek_beginning);
ElementLevelA = inDataStream.FindNextElement(sContext, UpperEltFound, MaxSizeToRead, AllowDummyElt);
while (ElementLevelA != NULL && UpperEltFound <= 0 && MaxSizeToRead > 0) {
if (IsFiniteSize())
MaxSizeToRead = GetEndPosition() - ElementLevelA->GetEndPosition(); // even if it's the default value
if (!AllowDummyElt && ElementLevelA->IsDummy()) {
ElementLevelA->SkipData(inDataStream, sContext);
delete ElementLevelA; // forget this unknown element
} else {
// more logical to do it afterward
ElementList.push_back(ElementLevelA);
ElementLevelA->Read(inDataStream, EBML_CONTEXT(ElementLevelA), UpperEltFound, FoundElt, AllowDummyElt, ReadFully);
// just in case
ElementLevelA->SkipData(inDataStream, EBML_CONTEXT(ElementLevelA));
}
if (UpperEltFound > 0) {
UpperEltFound--;
if (UpperEltFound > 0 || MaxSizeToRead <= 0)
goto processCrc;
ElementLevelA = FoundElt;
continue;
}
if (UpperEltFound < 0) {
UpperEltFound++;
if (UpperEltFound < 0)
goto processCrc;
}
if (MaxSizeToRead <= 0)
goto processCrc;// this level is finished
ElementLevelA = inDataStream.FindNextElement(sContext, UpperEltFound, MaxSizeToRead, AllowDummyElt);
}
if (UpperEltFound > 0) {
FoundElt = ElementLevelA;
}
}
processCrc:
EBML_MASTER_ITERATOR Itr, CrcItr;
for (Itr = ElementList.begin(); Itr != ElementList.end();) {
if ((EbmlId)(*(*Itr)) == EBML_ID(EbmlCrc32)) {
bChecksumUsed = true;
// remove the element
Checksum = *(static_cast<EbmlCrc32*>(*Itr));
CrcItr = Itr;
break;
}
++Itr;
}
if (bChecksumUsed)
{
delete *CrcItr;
Remove(CrcItr);
}
SetValueIsSet();
}
}
