macports: avoid dylib/link confusion

[rurban]

use true bundle/dylib extensions, avoid mixup, avoid hardcoded .so,
add -L/opt/local/lib -I/opt/local/include search paths for macports,
use libglfw.dylib, not libglfw3.dylib

not necesserily to be merged, but this is what I needed

[eriksvedang]

Nice, making it work well with macports would be great. I get a lot of errors when running the tests after this patch though. I think it has to do with the .bundle suffix. Run the tests with CARP_DEV=1 carp.

[daveyarwood]

@rurban Your instructions in INSTALL.md pointed me in the right direction to build Carp successfully! 🎉

I use Homebrew, not Macports, so my libffi is in a slightly different directory. What I ran was:

git clone https://github.com/eriksvedang/Carp.git
cd Carp
cmake . -DLIBFFI_INCLUDE_PATH=/usr/local/opt/libffi/lib/libffi-3.0.13/include/ -DLIBFFI_LIBRARY_PATH=/usr/local/opt/libffi/lib/
make

[chrisosaurus]

I find this a lot harder to reason about.

Where is the '3' needed for 'libglfw3.dylib' now coming from?

I would much prefer an if for each os, as previously done.

[chrisosaurus]

since @daveyarwood was helped by install instructions I think it is worth including those too.

[eriksvedang]

I (manually) added the changes suggested by @mkfifo and will now close this. Added you as a contributor to README.md, @rurban . Thanks for the help!