Makefile: move dep-check code to check-depends.sh

Make it possible to run the dependency check without the Makefile. This
is needed to split up the manual pages into the projects repositories,
so we can call check-depends.sh from there.

Related: OS#3385
Change-Id: I82a7efd7e9c265c82d1ba8a60856c892a15a7a33

Makefile

@@ -72,21 +72,5 @@ check:
 	cd OsmocomBB; $(MAKE) check
 	cd OsmoTRX; $(MAKE) check
 
-define check_dep_bin
-    @type $(1) >/dev/null 2>&1 || { echo >&2 "Binary '$(1)' not found in path, please install $(2)."; exit 1; }
-endef
-define check_dep_python2_module
-    @echo "import $(1)" | python2 - >/dev/null 2>&1 || { echo >&2 "Failed to import '$(1)' module, please install $(2)."; exit 1; }
-endef
-
 check-deps:
-	$(call check_dep_bin,mscgen,mscgen)
-	$(call check_dep_bin,xsltproc,libxslt)
-	$(call check_dep_bin,git,git)
-	$(call check_dep_bin,a2x,asciidoc)
-	$(call check_dep_bin,asciidoc,asciidoc)
-	$(call check_dep_bin,dblatex,dblatex)
-	$(call check_dep_bin,packetdiag,nwdiag)
-	$(call check_dep_bin,dot,graphviz)
-	$(call check_dep_bin,python2,python2)
-	$(call check_dep_python2_module,pychart,python2-pychart)
+	./check-depends.sh

check-depends.sh

@@ -0,0 +1,30 @@
+#!/bin/sh
+
+# $1: program name, $2: package name
+check_dep_bin() {
+	if ! type "$1" >/dev/null 2>&1; then
+		echo "Binary '$1' not found in path, please install $2."
+		exit 1
+	fi
+}
+
+# $1: module name, $2: package name
+check_dep_python2_module() {
+	if ! echo "import $1" | python2 - >/dev/null 2>&1; then
+		echo "Failed to import '$1' module, please install $2."
+		exit 1
+	fi
+}
+
+check_dep_bin mscgen mscgen
+check_dep_bin xsltproc libxslt
+check_dep_bin git git
+check_dep_bin a2x asciidoc
+check_dep_bin asciidoc asciidoc
+check_dep_bin dblatex dblatex
+check_dep_bin packetdiag nwdiag
+check_dep_bin dot graphviz
+check_dep_bin python2 python2
+check_dep_python2_module pychart python2-pychart
+
+echo "All dependencies installed!"