void ASF_MetaHandler::CacheFileData()
{
this->containsXMP = false;
XMP_IO* fileRef ( this->parent->ioRef );
if ( fileRef == 0 ) return;
ASF_Support support ( &this->legacyManager,0 );
ASF_Support::ObjectState objectState;
long numTags = support.OpenASF ( fileRef, objectState );
if ( numTags == 0 ) return;
if ( objectState.xmpLen != 0 ) {
// XMP present
XMP_Int32 len = XMP_Int32 ( objectState.xmpLen );
this->xmpPacket.reserve( len );
this->xmpPacket.assign ( len, ' ' );
bool found = ASF_Support::ReadBuffer ( fileRef, objectState.xmpPos, objectState.xmpLen,
const_cast<char *>(this->xmpPacket.data()) );
if ( found ) {
this->packetInfo.offset = objectState.xmpPos;
this->packetInfo.length = len;
this->containsXMP = true;
}
}
} // ASF_MetaHandler::CacheFileData
void ASF_MetaHandler::WriteTempFile ( XMP_IO* tempRef )
{
bool ok;
XMP_IO* originalRef = this->parent->ioRef;
ASF_Support support;
ASF_Support::ObjectState objectState;
long numTags = support.OpenASF ( originalRef, objectState );
if ( numTags == 0 ) return;
tempRef->Truncate ( 0 );
ASF_Support::ObjectIterator curPos = objectState.objects.begin();
ASF_Support::ObjectIterator endPos = objectState.objects.end();
for ( ; curPos != endPos; ++curPos ) {
ASF_Support::ObjectData object = *curPos;
// discard existing XMP object
if ( object.xmp ) continue;
// update header-object, when legacy needs update
if ( IsEqualGUID ( ASF_Header_Object, object.guid) && this->legacyManager.hasLegacyChanged( ) ) {
// rewrite header object
ok = support.WriteHeaderObject ( originalRef, tempRef, object, this->legacyManager, false );
if ( ! ok ) XMP_Throw ( "Failure writing ASF header object", kXMPErr_InternalFailure );
} else {
// copy any other object
ok = ASF_Support::CopyObject ( originalRef, tempRef, object );
if ( ! ok ) XMP_Throw ( "Failure copyinh ASF object", kXMPErr_InternalFailure );
}
// write XMP object immediately after the (one and only) top-level DataObject
if ( IsEqualGUID ( ASF_Data_Object, object.guid ) ) {
XMP_StringPtr packetStr = xmpPacket.c_str();
XMP_StringLen packetLen = (XMP_StringLen)xmpPacket.size();
ok = ASF_Support::WriteXMPObject ( tempRef, packetLen, packetStr );
if ( ! ok ) XMP_Throw ( "Failure writing ASF XMP object", kXMPErr_InternalFailure );
}
}
ok = support.UpdateFileSize ( tempRef );
if ( ! ok ) XMP_Throw ( "Failure updating ASF file size", kXMPErr_InternalFailure );
} // ASF_MetaHandler::WriteTempFile
void ASF_MetaHandler::UpdateFile ( bool doSafeUpdate )
{
bool updated = false;
if ( ! this->needsUpdate ) return;
XMP_IO* fileRef ( this->parent->ioRef );
if ( fileRef == 0 ) return;
ASF_Support support;
ASF_Support::ObjectState objectState;
long numTags = support.OpenASF ( fileRef, objectState );
if ( numTags == 0 ) return;
XMP_StringLen packetLen = (XMP_StringLen)xmpPacket.size();
this->legacyManager.ExportLegacy ( this->xmpObj );
if ( this->legacyManager.hasLegacyChanged() ) {
this->legacyManager.SetDigest ( &this->xmpObj );
// serialize with updated digest
if ( objectState.xmpLen == 0 ) {
// XMP does not exist, use standard padding
this->xmpObj.SerializeToBuffer ( &this->xmpPacket, kXMP_UseCompactFormat );
} else {
// re-use padding with static XMP size
try {
XMP_OptionBits compactExact = (kXMP_UseCompactFormat | kXMP_ExactPacketLength);
this->xmpObj.SerializeToBuffer ( &this->xmpPacket, compactExact, XMP_StringLen(objectState.xmpLen) );
} catch ( ... ) {
// re-use padding with exact packet length failed (legacy-digest needed too much space): try again using standard padding
this->xmpObj.SerializeToBuffer ( &this->xmpPacket, kXMP_UseCompactFormat );
}
}
}
XMP_StringPtr packetStr = xmpPacket.c_str();
packetLen = (XMP_StringLen)xmpPacket.size();
if ( packetLen == 0 ) return;
// value, when guessing for sufficient legacy padding (line-ending conversion etc.)
const int paddingTolerance = 50;
bool xmpGrows = ( objectState.xmpLen && (packetLen > objectState.xmpLen) && ( ! objectState.xmpIsLastObject) );
bool legacyGrows = ( this->legacyManager.hasLegacyChanged() &&
(this->legacyManager.getLegacyDiff() > (this->legacyManager.GetPadding() - paddingTolerance)) );
if ( doSafeUpdate || legacyGrows || xmpGrows ) {
// do a safe update in any case
updated = SafeWriteFile();
} else {
// possibly we can do an in-place update
if ( objectState.xmpLen < packetLen ) {
updated = SafeWriteFile();
} else {
// current XMP chunk size is sufficient -> write (in place update)
updated = ASF_Support::WriteBuffer(fileRef, objectState.xmpPos, packetLen, packetStr );
// legacy update
if ( updated && this->legacyManager.hasLegacyChanged() ) {
ASF_Support::ObjectIterator curPos = objectState.objects.begin();
ASF_Support::ObjectIterator endPos = objectState.objects.end();
for ( ; curPos != endPos; ++curPos ) {
ASF_Support::ObjectData object = *curPos;
// find header-object
if ( IsEqualGUID ( ASF_Header_Object, object.guid ) ) {
// update header object
updated = support.UpdateHeaderObject ( fileRef, object, legacyManager );
}
}
}
}
}
if ( ! updated ) return; // If there's an error writing the chunk, bail.
this->needsUpdate = false;
} // ASF_MetaHandler::UpdateFile