I converted https://github.com/FirefoxGraphics/qcms and then refactored it to mostly safe Rust. I ran into a number of issues https://github.com/immunant/c2rust/issues?q=is%3Aissue+autho... but it generally worked ok.

I found refactoring the resulting Rust code somewhat error prone and didn't have great success with the automated tools. I'd recommend having a good test suite and suggest adjusting the C before the conversion to avoid using C features that don't translate well like the C preprocessor.