Disable linking with Fink or DarwinPorts.

It may be desirable for the compiler to disable linking against Fink
or DarwinPorts, especially if both are installed on the system and
the user wants GIT to be linked specifically to only one of them.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Makefile

@@ -37,6 +37,18 @@ all:
 # tests.  These tests take up a significant amount of the total test time
 # but are not needed unless you plan to talk to SVN repos.
 #
+# Define NO_FINK if you are building on Darwin/Mac OS X, have Fink
+# installed in /sw, but don't want GIT to link against any libraries
+# installed there.  If defined you may specify your own (or Fink's)
+# include directories and library directories by defining CFLAGS
+# and LDFLAGS appropriately.
+#
+# Define NO_DARWIN_PORTS if you are building on Darwin/Mac OS X,
+# have DarwinPorts installed in /opt/local, but don't want GIT to
+# link against any libraries installed there.  If defined you may
+# specify your own (or DarwinPort's) include directories and
+# library directories by defining CFLAGS and LDFLAGS appropriately.
+#
 # Define PPC_SHA1 environment variable when running make to make use of
 # a bundled SHA1 routine optimized for PowerPC.
 #
@@ -254,15 +266,17 @@ ifeq ($(uname_S),Darwin)
 	NEEDS_SSL_WITH_CRYPTO = YesPlease
 	NEEDS_LIBICONV = YesPlease
 	NO_STRLCPY = YesPlease
-	## fink
-	ifeq ($(shell test -d /sw/lib && echo y),y)
-		ALL_CFLAGS += -I/sw/include
-		ALL_LDFLAGS += -L/sw/lib
+	ifndef NO_FINK
+		ifeq ($(shell test -d /sw/lib && echo y),y)
+			ALL_CFLAGS += -I/sw/include
+			ALL_LDFLAGS += -L/sw/lib
+		endif
 	endif
-	## darwinports
-	ifeq ($(shell test -d /opt/local/lib && echo y),y)
-		ALL_CFLAGS += -I/opt/local/include
-		ALL_LDFLAGS += -L/opt/local/lib
+	ifndef NO_DARWIN_PORTS
+		ifeq ($(shell test -d /opt/local/lib && echo y),y)
+			ALL_CFLAGS += -I/opt/local/include
+			ALL_LDFLAGS += -L/opt/local/lib
+		endif
 	endif
 endif
 ifeq ($(uname_S),SunOS)