Add NULL checks as needed

[meshula]

Add NULL checks as needed. c.f. AcademySoftwareFoundation/OpenTimelineIO@9fbf870

[KarthikRIyer]

The NULL checks in the commit are for parameters that are either optional or have default values in the C++ API. The check for this have been added.

Is there anything else to do in this issue?

[meshula]

To clarify the issue, this commit - AcademySoftwareFoundation/OpenTimelineIO@9fbf870 - shows an example of preventing crashes from null dereferencing by checking parameters and handling them in some manner. That particular one I fixed already because I encountered it in practice, and so made a fix. This issue is about doing an audit of all the code, which is a huge task. It might make sense to make a list of source files in this issue, with check boxes, like this

• file1.cpp
• file2.cpp

and just work through them little by little as we have time.

[KarthikRIyer]

👍

[meshula]

Path: copentime

• ▕─ errorStatus.cpp
• ▕─ rationalTime.cpp
• ▕─ timeRange.cpp
• ▕─ timeTransform.cpp

Path: copentimelineio

• ▕─ any.cpp
• ▕─ anyDictionary.cpp
• ▕─ anyVector.cpp
• ▕─ clip.cpp
• ▕─ composable.cpp
• ▕─ composableRetainerVector.cpp
• ▕─ composableVector.cpp
• ▕─ composition.cpp
• ▕─ deserialization.cpp
• ▕─ effect.cpp
• ▕─ effectRetainerVector.cpp
• ▕─ effectVector.cpp
• ▕─ errorStatus.cpp
• ▕─ externalReference.cpp
• ▕─ freezeFrame.cpp
• ▕─ gap.cpp
• ▕─ generatorReference.cpp
• ▕─ item.cpp
• ▕─ linearTimeWarp.cpp
• ▕─ mapComposableTimeRange.cpp
• ▕─ marker.cpp
• ▕─ markerRetainerVector.cpp
• ▕─ markerVector.cpp
• ▕─ mediaReference.cpp
• ▕─ missingReference.cpp
• ▕─ optionalPairRationalTime.cpp
• ▕─ retainerPairComposable.cpp
• ▕─ safely_typed_any.cpp
• ▕─ serializableCollection.cpp
• ▕─ serializableObject.cpp
• ▕─ serializableObjectRetainerVector.cpp
• ▕─ serializableObjectVector.cpp
• ▕─ serializableObjectWithMetadata.cpp
• ▕─ serialization.cpp
• ▕─ stack.cpp
• ▕─ stackAlgorithm.cpp
• ▕─ timeEffect.cpp
• ▕─ timeline.cpp
• ▕─ track.cpp
• ▕─ trackAlgorithm.cpp
• ▕─ trackVector.cpp
• ▕─ transition.cpp
• ▕─ typeRegistry.cpp
• ▕─ unknownSchema.cpp

[rogergodspeed]

Is this only an issue where you are reinterpret_cast'ing? If so only errorStatus.cpp and rationalTime.cpp use that in copentime. The issue might not be so widespread elsewhere either.