Add frozen nrfutil tool for macOS, and instructions for generating with cx_freeze.

Author: tdicola

boards.txt

@@ -48,7 +48,12 @@ feather52.build.lfclk_flags=-DUSE_LFXO
 
 feather52.build.nrfutil=nrfutil
 feather52.build.nrfutil.windows={runtime.platform.path}/tools/nrfutil-0.5.2/binaries/win32/nrfutil.exe
-feather52.build.nrfutil.macosx=/usr/local/bin/nrfutil
+# Legacy MacOS nrfutil location, this is for when people had it globally
+# installed and is left just for reference:
+# feather52.build.nrfutil.macosx=/usr/local/bin/nrfutil
+# Frozen MacOS nrfutil location, this uses a frozen or pre-built standalone
+# version of nrfutil included in the BSP (no manual install required):
+feather52.build.nrfutil.macosx={runtime.platform.path}/tools/nrfutil-0.5.2/binaries/macos/nrfutil
 
 feather52.menu.debug.l0=Level 0 (Release)
 feather52.menu.debug.l0.build.debug_flags=-DCFG_DEBUG=0

tools/nrfutil-0.5.2/MACOS_FREEZE.txt

@@ -0,0 +1,53 @@
+Instructions for how to produce a frozen nrfutil executable on MacOS
+
+These instructions describe how to use the cx_freeze tool to generate a
+standalone self-contained (or 'frozen') version of the nrfutil script.  This is
+useful for distribution so users don't need to manually install it and deal
+with potential python version headaches and more.
+
+Initial setup (do this once):
+- Get cx_freeze installed for _Python 2.7_.  Very important to use Python 2 as
+  the nrfutil script doesn't work with Python 3 and cx_freeze will use whichever
+  version of Python it's run with to build the exe (i.e. you need to run
+  cx_freeze with Python 2.7).  Assuming you have homebrew installed:
+  - Update python 2 in homebrew to the latest version, and reinstall just to
+    fix odd issues like links to old dynamic libraries that might be missing,
+    etc.  Run:
+      brew update
+      brew reinstall python
+
+    Or if you never had homebrew python2 installed run:
+      brew install python
+
+    Now just to make sure homebrew python is setup and linked as the 'active'
+    python run:
+      brew unlink python && brew link python
+  - At this point when you run python or pip you should be using homebrew
+    python.  Do not continue until this is true.
+  - Install cx_freeze for homebrew python 2:
+
+      pip2 install cx_freeze
+
+    Make sure this completes successfully.  You should be able to run the
+    cxfreeze script and verify it shows usage info:
+
+      cxfreeze
+- Install nrfutil dependencies.  Be sure to install them into homebrew's python
+  2 as this is what cx_freeze will run from and use to find dependencies. Run
+  from this directory:
+
+    pip2 install -r requirements.txt
+    python setup.py install
+- That's it, you should be setup with cx_freeze on homebrew python 2 and all
+  the nrfutil dependencies ready to go.
+
+Generating a frozen nrfutil:
+- You'll run a cxfreeze command to generate the executable and place it in
+  the binaries/macos location under the name nrfutil.  From this directory run:
+
+    cxfreeze ./nordicsemi/__main__.py --target-dir binaries/macos --target-name nrfutil
+
+  If it completes without an error message then everything should be good.  Try
+  running ./binaries/macos/nrfutil to make sure you can get usage info.  The
+  boards.txt should already be pointing to this file so try using it in Arduino
+  to upload to a board.