Issue #1874 Cast to unsigned char for isspace.

[pennelee]

Fix for: https://github.com/AcademySoftwareFoundation/OpenColorIO/issues/1874

Cast to unsigned char before using std:isspace().

From cppreference:

Like all other functions from cctype, the behavior of std::isspace is undefined if the argument's value is neither representable as unsigned char nor equal to EOF. To use these functions safely with plain chars (or signed chars), the argument should first be converted to unsigned char

[linux-foundation-easycla[bot]]

The committers listed above are authorized under a signed CLA.

• :white_check_mark: login: pennelee / name: PenneLee (0061ab109ff46bd19d718df6c2fe387085d1148c, f793dbc28af288894e0d3c7be744488921f41040, 65c4059a9edd364f7e6609191a600df98cc8bf1d)
• :white_check_mark: login: doug-walker / name: Doug Walker (c20132ef61eb2a32dff3a29dfde7e2c672008d30)

[doug-walker]

Thanks for this fix @pennelee. Please let us know if you have problems getting the CLA signed.

Would you please add a unit test along the lines of what Remi suggested?

[pennelee]

Hi @doug-walker , Yes, Sean is working on the CLA for the company, hope it will be sorted out soon.

Sure I can add the unit test Remi suggested, I had it locally but didn't push the change.

[pennelee]

Hi @doug-walker, I have added the unit test and also CLA is now signed, and I am approved as contributor.

[doug-walker]

Thanks for getting the CLA signed @pennelee. Could you add the comment I suggested to the unit test please?

[pennelee]

I'm sorry @doug-walker , which comment do you refer to?

[doug-walker]

Apologies @pennelee, I had made a comment but it had not been submitted. You should see it now I think.

[pennelee]

@doug-walker Thanks Doug I have updated with the unit test comment.

[pennelee]

Hi @remia , Could you please help to review this PR when you have time? Thank you!