Crash in ReadChunk()

thomasmfields

Hi there,

Using cineware SDK v22.008 (VS2013 libs), I'm getting a crash when trying to process the file attached. The crash stack is:

 	FwdFX_d.fx!cineware::PrivateChunk::ReadChunk(class cineware::HyperFile *,bool,bool)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadObject(class cineware::HyperFile *,bool)	Unknown
 	FwdFX_d.fx!cineware::MoGraphFractureVoronoiObject::Read(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::BaseObject::HandleSubChunk(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadChunk(class cineware::HyperFile *,bool,bool)	Unknown
 	FwdFX_d.fx!cineware::RootObject::HandleSubChunk(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadChunk(class cineware::HyperFile *,bool,bool)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadObject(class cineware::HyperFile *,bool)	Unknown
 	FwdFX_d.fx!cineware::BaseObject::HandleSubChunk(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadChunk(class cineware::HyperFile *,bool,bool)	Unknown
 	FwdFX_d.fx!cineware::RootObject::HandleSubChunk(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadChunk(class cineware::HyperFile *,bool,bool)	Unknown
 	FwdFX_d.fx!cineware::RootList2D::HandleSubChunk(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::RootObject::HandleSubChunk(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadChunk(class cineware::HyperFile *,bool,bool)	Unknown
 	FwdFX_d.fx!cineware::BaseDocument::HandleSubChunk(class cineware::HyperFile *,int,int)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadChunk(class cineware::HyperFile *,bool,bool)	Unknown
 	FwdFX_d.fx!cineware::PrivateChunk::ReadObject(class cineware::HyperFile *,bool)	Unknown

and the log contains:

First-chance exception at 0x000000001F5BDA64 (FwdFX_d.fx) in FX_d.exe: 0xC0000005: Access violation reading location 0xFFFFFFFFFFFFFFFF.

Any clues as to what is going wrong here and how I can fix it?

The file is here: model loop 7.c4d

Regards,
Tom

jana

Hello @thomasmfields,

Welcome to the Maxon developers forum and its community, it is great to have you with us!

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About your First Question

Thanks a lot for reaching out. To support you, please provide a code snippet that we can reproduce the issue.
What do you want to achieve?

Thanks and Cheers
Jana

thomasmfields

Hi Jana,

I'd like it not to crash, please. My code looks like this:

fn.SetMemoryReadMode(data, size); // The contents of the file are in "data".
cineware::AlienBaseDocument *c4dDoc = NewObj(cineware::AlienBaseDocument);
cineware::HyperFile *c4dFile = NewObj(cineware::HyperFile);
if (c4dDoc && c4dFile)
{
	if (c4dFile->Open(DOC_IDENT, fn, cineware::FILEOPEN_READ))
	{
		if (c4dDoc->ReadObject(c4dFile, true))
		{
		}
	}
}

Are you able to reproduce the issue?

Regards,
Tom

j_uhlig

Hi Tom,

can you please try the following:

does it work if you load the same data from disk
can you try with LoadDocument(fn, SCENEFILTER::SCENEFILTER_OBJECTS | SCENEFILTER::SCENEFILTER_MATERIALS)
And how did you load the file into memory?

Cheers
Jens

thomasmfields

Hi Jens,

I get the same error stack when I do the following:

cineware::Filename myFile("model loop 7.c4d");
cineware::BaseDocument *baseDoc = LoadDocument(myFile, cineware::SCENEFILTER::SCENEFILTER_OBJECTS | cineware::SCENEFILTER::SCENEFILTER_MATERIALS);

I load the file into memory using my own file stream API, which is used successfully elsewhere and with other c4d files. I'm using ReadFile() and GetFileSizeEx()

Regards,
Tom

j_uhlig

Hi Tom,

I could confirm the issue!

You can fix this in "c4d_fracturevoronoidata.h" line 52 like this:

RootObject* _head = nullptr;

Please let me know if this works for you.
Cheers
Jens

thomasmfields

Hi Jens,

That fix works for us. This is excellent. Thank you very much.

Regards,
Tom