resolve any issues from coverity static analysis

[trgill]

https://docs.google.com/document/d/1BbO6Xt7VVJtdDeHNZT3k9GP282PtynTMFL0Du263Kw4/edit?usp=sharing

[trgill]

@prajnoha Coverity doesn't like assignments in "if" statements. For example:

if (!(alloc_step = buf->stat.init.alloc_step))

Of cases where we use (like above) or:
!integer_variable

I'm thinking I'll just mark these as style issues rather than change the code. That ok with you?

[prajnoha]

Sure, let's keep those as they are for now - they're throughout the whole code so that would be lots of changes.

[prajnoha]

PR #58

[trgill]

PR #60