Update Makefile

fix make uninstall is very destructive and coreutils

rockymadden#20 (comment)

Makefile

@@ -1,13 +1,22 @@
 .DEFAULT_GOAL := stub
+#### Installation directories 
 bindir ?= ./build/bin
 logdir ?= ./build/var/log
+
 uname := $(shell uname -s)
+coreutils := $(shell brew list coreutils 2>/dev/null)
 
 clean: | uninstall
 
 install: | stub
 	@rsync -a src/ ${bindir}/
-ifeq (${uname}, Darwin)
+
+
+ifeq (${uname}, Darwin)	
+ifndef coreutils
+	$(error The 'coreutils' package is required for this operation. https://www.gnu.org/software/coreutils/. \
+                 Please install it. brew install coretutils));
+endif
 	@$(eval _bindir := $(shell greadlink -f ${bindir}))
 	@$(eval _logdir := $(shell greadlink -f ${logdir}))
 	@sed -i ''  "s|bindir=|bindir=${_bindir}|g" ${bindir}/somafm
@@ -32,7 +41,9 @@ test-unit: | install
 	@bats test/unit
 
 uninstall:
-	@rm -rf ${bindir}
-	@rm -rf ${logdir}
+	@if test -f ${bindir}/somafm; then rm ${bindir}/somafm; fi
+	@if test -f ${logdir}/somafm.bats.logs; then rm ${logdir}/somafm.bats.logs; fi
+	@if [ "$(ls -A $bindir)" ]; then rm -rf ${bindir}; fi
+	@if [ "$(ls -A $logdir)" ]; then rm -rf ${logdir}; fi
 
 .PHONY: clean install stub test test-integration test-unit uninstall