[PATCH 2 of 7 v3 stable osx-packaging] osx: add support for dumping built dmg into OUTPUTDIR

[Kevin Bullock]

# HG changeset patch
# User Augie Fackler <augie at google.com>
# Date 1461038242 14400
#      Mon Apr 18 23:57:22 2016 -0400
# Branch stable
# Node ID 13219c6c0aa43fc3a29efb0af20ac6934906337c
# Parent  1a879471e08e074a2a93ab5697c63089664a7950
osx: add support for dumping built dmg into OUTPUTDIR

diff --git a/Makefile b/Makefile
--- a/Makefile
+++ b/Makefile
@@ -161,8 +161,11 @@ osx:
 	rm -rf dist/mercurial-*.mpkg
 	python -m bdist_mpkg.script_bdist_mpkg setup.py --
 	python contrib/fixpax.py dist/mercurial-*.mpkg/Contents/Packages/*.pkg/Contents/Archive.pax.gz
-	mkdir -p packages/osx
-	N=`cd dist && echo mercurial-*.mpkg | sed 's,\.mpkg$$,,'` && hdiutil create -srcfolder dist/$$N.mpkg/ -scrub -volname "$$N" -ov packages/osx/$$N.dmg
+	OUTPUTDIR=$${OUTPUTDIR:=packages/osx} && \
+	  mkdir -p $$OUTPUTDIR && \
+	  N=`cd dist && echo mercurial-*.mpkg | sed 's,\.mpkg$$,,'` && \
+	  hdiutil create -srcfolder dist/$$N.mpkg/ -scrub -volname "$$N" \
+	    -ov $$OUTPUTDIR/$$N.dmg
 	rm -rf dist/mercurial-*.mpkg
 
 deb: